sorry nih, postingan pertama kemaren tanpa persiapan.
sebenarnya itu adalah transletan jurnal dari tugas refaratku kemaren di bagian Bedah Mulut. ini jurnal aslinya:

© S F Worrall 1998
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AVOIDING AND MANAGING COMPLICATIONS
IN MINOR ORAL SURGERY
From: Avoiding complications in minor oral surgery. In: Ward-Booth, P., Hausaman
J-E., Schendel, S. (eds). Maxillofacial Surgery. Edinburgh: Churchill Livingstone,
1999, 1591-1610.
Stephen F. Worrall. MD, FDSRCS, FRCS.
mail@millennium3.org.uk
http://millennium3.org.uk
© S F Worrall 1998
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“In all things success depends upon previous preparation, and without such
preparation there is sure to be failure.” (Confucius 550 - c 478 BC)
INTRODUCTION
The majority of complications involve the operative site and may occur
perioperatively or postoperatively. The prevention and management of these
categories of complications is the aim of this chapter. While most complications are
fortunately minor, occasionally, major life-threatening systemic complications such as
a respiratory or cardiac arrest will occur. These medical emergencies are often totally
unexpected and likely to become more common as the general age of the population
increases and more patients with severe underlying medical conditions require oral
surgical procedures. It is beyond the scope of this chapter to cover in detail the
necessary precautions needed for, and the management of, patients with complicating
medical and dental histories and the reader is referred to the many excellent texts
available that cover this subject in depth (1, 2).
In many ways the term “minor oral surgery” is unfortunate and misleading as it
implies that the procedure to be performed is simple and that postoperative sequelae
are negligible. It may also give the false impression that less skill and care is required
than for the performance of “major oral surgery”. This is a dangerous misconception.
There can be few experienced oral & maxillofacial surgeons who have not been
humbled by a lowly third molar tooth. Moreover, complications following such
surgery are poorly tolerated by patients whose expectation is that minor surgery
should not produce major morbidity.
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Following the axiom that prevention is better than cure, the best way to
manage complications is not to produce them in the first place. For while a few
complications following minor oral surgery are truly unavoidable, most can and
should be prevented.
Preoperative Assessment And Treatment Planning
It is a sine qua non of all medical and surgical practice that the clinician must
be in possession of the requisite expertise and skill to perform the scheduled
procedure. The wise surgeon is aware of any personal limitations in this area and will
not elect to perform any operation beyond his or her capabilities. To a certain extent
and with some qualifications this principle may also be applied to managing
complications. If a surgeon lacks the ability to remove a fractured and retained root or
close an oro-antral fistula then one must seriously question the wisdom of embarking
on the extraction of the tooth in the first place. Furthermore, all but the simplest of
procedures will require the help of a skilled and knowledgeable assistant. This is
particularly important for junior surgeons in training who are all to often left to “finish
the list” with only the theatre scrub nurse to act as first assistant.
Medical History Taking And Resuscitation Training
The majority of patients who are at increased risk of developing surgical and
medical complications should be identified preoperatively following the taking of a
comprehensive medical and dental history which should be updated at each
subsequent visit. Specific questions should be asked concerning previous cardiac and
respiratory diseases, pregnancy, diabetes, excessive bleeding following minor injuries,
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current and past drug therapy including anti-coagulants and steroids, previous local
and general anaesthetic experience and drug allergies. A history of difficult
extractions, post extraction haemorrhage and radiotherapy to the operative area should
be taken seriously.
Obviously, the management of the more serious complications of minor oral
surgery will be beyond the capability of the relatively inexperienced surgeon,
especially if they occur outwith the hospital environment where there is ready access
to all the necessary equipment, drugs and support services. In this situation the
operating surgeon has a duty of care to the patient to recognise that a complication has
arisen and to consult with or refer the patient to a more experienced colleague (usually
the local consultant oral & maxillofacial surgeon) for advice and treatment.
Depending on the severity of the problem referral via the telephone rather than the
traditional letter may be more appropriate. To err is human but failure to recognise
the error and take immediate and appropriate action to remedy it is negligent.
It is essential that all those directly involved in treating patients are fully
conversant with the theory and practice of basic life support and resuscitation. This
applies to the surgeon who only ever treats patients under local anaesthetic as well as
those who routinely employ sedation or general anaesthesia in their practice. Once
learned, basic life support skills must be regularly practised by the entire surgical team
until everyone is fully conversant with their individual roles. Emergency medical and
resuscitation equipment must be regularly checked, maintained and serviced.
Simple and seemingly obvious measures such as keeping a list of emergency
service contact numbers by the telephone, which should ideally be in the patient
treatment area, can save valuable and potentially life saving minutes should a patient
suffer a cardiac arrest.
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Surgical Equipment
Most minor oral surgical procedures do not require large numbers of
instruments. Nonetheless, the surgeon must satisfy him or herself before embarking
on the procedure that all the equipment necessary to complete the procedure safely
and deal with any complications commensurate with their experience are available,
clean and sterile. Perhaps one of the most often neglected items of surgical kit is the
operating light. A light that is just adequate to visualise a lower third molar may be
totally inadequate when one’s attention turns to removing the opposing partially
erupted upper third molar. Especially if bone needs to be removed in order to
facilitate tooth delivery. Lack of adequate lighting can make an otherwise
straightforward procedure difficult and a difficult procedure almost impossible.
Similar consideration should be given to the suction apparatus to be used. In the
United States (US) clinicians are required to have some form of suction apparatus
available at all times and also to have a backup battery supply in case of mains power
failure. While a low volume salivary aspirator may easily deal with the minimal
bleeding consequent on raising a mucoperiosteal flap it will be unable to cope with the
sometimes alarming haemorrhage that can arise from a severed nutrient vessel or
inferior alveolar artery. The threat to the patient’s airway and the likely consequences
are obvious.
Radiographs
If damage to vital structures is to be avoided the surgeon must have a very
clear understanding of the anatomy of the operative area including the presence of any
local variations that may complicate an otherwise normal procedure (Figure 1). Only
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then can a surgical treatment plan be produced. This process must take place prior to
each and every operative procedure to be performed. Minor oral surgical procedures
involving the hard tissues require that information derived from clinical examination
of the patient is supplemented by preoperative imaging. For the most part this means
plain radiographs of the area. It is axiomatic that radiographs must show the area to
be operated on, and they must also be of good quality to enable the differentiation of
adjacent structures from each other. A radiograph showing a third molar that is
blurred, overexposed and streaked is worse than useless and basing an operation on
such a radiograph is foolhardy. For apicectomies an intraoral radiograph is acceptable
providing it also shows the apices of the adjacent teeth on either side of the index
tooth. If an apicectomy is to be performed and a cyst enucleated the entire cyst outline
should be visible on the planning radiograph. Radiographs of lower third molars must
show (3, 4):
• The entire third molar and hence the type of impaction
• The entire configuration of the second and first molars if present
• The immediate investing bone and the entire pericoronal space
• The relationship of the third molar tooth/roots to the neurovascular canal
• The presence and extent of any associated pathological changes
In the majority of situations these requirements will preclude the sole use of
the intraoral periapical radiograph for preoperative planning of lower third molar
extractions. The use of survey radiographs such as the lateral oblique view and
rotational tomography allow these requirements to be met (3).
The orthopantomogram (OPT) is probably the commonest type of rotational
tomogram in use in the United Kingdom (UK) and provides an excellent view of all
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the teeth and related structures on one film. A preoperative OPT or equivalent
radiograph is a mandatory investigation prior to extracting any lower third molar,
regardless of its eruption status and type of impaction. If there is any doubt over the
relationship of the tooth to the neurovascular canal on the preoperative OPT a high
quality intraoral radiograph of the area should also be obtained. Although perhaps not
essential, it is a wise precaution to obtain a radiograph prior to extracting any tooth if
unpleasant surprises are to be minimised. Again the OPT is ideal for this purpose.
All radiographs should be indelibly marked with the patients’ name or case note
number and thoroughly checked to ensure that they are correctly orientated with
respect to right and left.
Local Anaesthesia
Where a local anaesthetic is to be given, as with all drugs it is vital to ensure
that the solution is unused and not past its expiry date. An aspirating syringe or
technique should be used in all cases to avoid intravascular injections. Where local
anaesthetic infiltrations into the periodontal ligament are used it is important to use a
specially designed syringe that not only delivers small increments of solution but also
fully encloses the glass cartridge. Using a normal dental syringe for ligamentous
injections will frequently result in fracture or explosion of the local anaesthetic
cartridge due to the high pressures generated. The danger to patient and surgeon alike
from flying glass are obvious and avoidable.
Occasionally, patients are labelled as being “resistant” to local anaesthetics.
This usually centres around failure to achieve surgical analgesia with an inferior
alveolar nerve block. Once local infection has been exclude as a cause of failure to
achieve surgical analgesia the commonest cause is faulty technique. If the surgeon is
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sure that his or her technique is correct it is likely that there is a local anatomical
variation in the region of the lingula. This may be due to an abnormally high or low
foramen or the lingula itself may be larger than normal presenting a physical barrier to
the hypodermic needle. Close inspection of the OPT in the region of the lingula will
usually show the problem. Thereafter, slight variation in technique, usually injecting a
centimetre or so higher resolves the problem.
If after repositioning the syringe and repeating the injection surgical analgesia
is still not achieved, in order to avoid unwanted toxicity and possible cardiac
complications it is important that the surgeon does not continue to inject more and
more anaesthetic in the blind hope of success. The maximum safe dose of lignocaine
containing a vasoconstrictor is 7.0 mg/Kg (0.35 ml/Kg of a 2% solution) and the total
dose of adrenaline should not exceed 200μg (16 ml of a 1:80,000 solution) (2).
Obtaining Patient Consent
Prior to performing any operative procedure the surgeon must obtain the
patient’s consent for treatment. Failure to obtain consent will leave the surgeon open
to a claim for negligence and possible criminal prosecution for battery. Consent must
be given voluntarily and the patient must be capable of understanding the proposed
treatment, have been appropriately informed beforehand and given the opportunity to
ask any questions regarding their treatment (5). In some circumstances this may
require an interpreter to be present and for multi-lingual information and consent
sheets to be available.
It is vital to understand that obtaining consent does not mean simply requesting
the patient’s verbal permission to submit themselves to treatment. In order for a
© S F Worrall 1998
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patient to adequately consent to an operation or treatment he or she must be fully
informed and be in possession of and understand the likely consequences and any
complications of that treatment. Moreover, it is extremely important that the patient is
made fully aware of the advantages and disadvantages of any alternative management
strategies to the planned treatment. In many cases this may include no treatment at all.
The type of anaesthetic to be used and any possible side effects and complications
such as drug reactions and phlebitis must also be fully discussed with the patient when
obtaining consent.
If a patient suffers a complication of a procedure which he was not warned
about preoperatively, without suggesting negligence, the surgeon may be sued for
breach of his duty of care to the patient (5).
Much debate has taken place concerning which complications patients should
be explicitly warned about. It has been suggested that patients should be specifically
warned about any complication that occurs with a minimum frequency between 1%
and 10% (6). However, it is currently accepted that patients should receive specific
warnings about any temporary condition that occurs in 5% or more of cases and any
permanent condition that occurs in 0.5% of cases (7). This means that all patients
should be warned about the risks of postoperative pain, bleeding, bruising, swelling
and limitation of function. Patients undergoing lower third molar removal must be
warned about the risk of lingual and inferior alveolar nerve anaesthesia, paraesthesia
and dyseasthesia. It is thus of some concern that a recent study showed that 4% of UK
oral & maxillofacial surgeons did not routinely warn their patients about possible
nerve damage following lower third molar surgery (8).
Similarly, patients undergoing procedures in the territory of the terminal
divisions of the facial nerve such as skin biopsies, botulinum toxin injections for
© S F Worrall 1998
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masseteric hypertrophy and arthrocentesis/arthroscopy etc must be warned about the
possibility of permanent facial weakness. It is also important to ensure that patients
(especially those caring for young children at home) are aware that they may well need
to take leave of absence from work and require help and support for several days postoperatively.
Unfortunately, although giving verbal warnings as outlined above will ensure
that the surgeon complies with the “letter of the law” they may not be sufficient to
ensure that he or she complies with the “spirit of the law”. Almost 50% of patients
may fail to recall being verbally warned about at least one complication
postoperatively (5). Patient recall of preoperative warnings and by implication the
extent to which their consent was fully informed can be increased by the use of written
information to supplement the standard verbal warnings (9, 10). Audio and video
tapes can also be used during the consultation and while obtaining patient consent.
These have the benefit of standardisation and ensuring that all the points deemed to be
relevant are covered for every patient.
It is important that consent is obtained from the patient not only preoperatively
but also in quiet surroundings, before any drugs have been administered and in an area
remote from that where the procedure is to be performed (11). This means that it is
unacceptable for a patient to be interviewed and consented by the operating surgeon in
the anaesthetic room immediately prior to the operation being performed.
The clinician charged with obtaining the patients’ consent must have a clear
understanding of the procedure to be performed and the possible complications if he
or she is to be able to adequately answer patients’ questions and concerns. This task is
frequently delegated to the most junior member of the team who is often too
inexperienced to obtain fully informed patient consent and has probably never been
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instructed on the medico-legal requirements of doing so (12). When completing the
proposed treatment section of the consent form the clinician must always consult the
relevant sections in the patients’ case notes and satisfy himself or herself that the
patient is being consented for the intended treatment. One must never rely on
operating theatre lists or departmental theatre books etc for this information. All too
often these records will be incorrect due to typographical or transcription errors. If
there is any doubt concerning the exact nature of the treatment proposed the
supervising clinician, usually the consultant oral & maxillofacial surgeon should be
consulted.
Everyone involved in obtaining patient consent in the UK should read and
understand the National Health Service Executive document A guide to consent for
examination and treatment (13).
Children under the age of 16 years (18 in the US unless the patient is married)
may give or withhold their consent for treatment without recourse to their parent or
guardian if the clinician believes that they are mentally capable of making an informed
decision. Whenever the clinician is not satisfied that a child is able to fully
understand the proposed procedures and their complications, consent must be sought
from the child’s parent or legal guardian except in emergency situations where there is
insufficient time to obtain it (13). In exceptional circumstances, and after full
discussion with the child’s parents in the presence of a witness, if the clinician
believes that a parent’s refusal to give consent for treatment is likely to prejudice the
continuing health of the child, he or she may seek to have the child made a ward or
court and request consent from a judge. If time does not permit this process, then the
surgeon in charge of the child’s care (normally the consultant oral & maxillofacial
surgeon) should seek and obtain a written report from a consultant colleague
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supporting the view that the child’s life would be in danger if treatment were to be
withheld. Where adult patients lack the mental capacity to give informed consent noone
may give consent on their behalf although the law allows treatment to be
performed provided it can be demonstrated to be in the best interests of the patient.
Such treatments should be discussed with the patients’ next of kin where possible but
ultimately the decision to proceed with treatment rests with the clinician in charge of
the patients’ care.
Provided the surgeon follows the above procedures and is demonstrably acting
in the patient’s best interests it is unlikely that his or her actions will be criticised by a
court or their professional body (13). Indeed, in certain circumstances failing to
provide necessary treatment may be construed as negligent. If time permits, the
surgeon would be wise to consult his or her medical indemnity association to seek
expert legal guidance before commencing any treatment for which the patients’
written consent has not been obtained.
Having obtained fully informed consent, all warnings and explanations given
should be recorded in the case notes and the patient or parent requested to sign a
consent form stating that they have been informed of, and understand the nature and
likely consequences of the procedure. Specimen consent forms which conform to the
above standards and guidelines are available for patients being treated within the UK
National Health Service (13). A patients’ signature on a consent form in the absence
of having obtained fully informed consent is no protection in law against a claim for
failing in one’s duty of care to the patient.
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Final Checks
Not infrequently, patients will have been on a waiting list for some time prior
to their operation. It is vitally important to check that the problem for which they are
about to be operated on has not resolved and no longer requires treatment or that the
original signs and symptoms have not altered such as to present a different diagnosis
and treatment plan to the original ones. In this situation, and if operative treatment is
still indicated the entire process of obtaining informed consent should be repeated.
Written consent should be contemporary with the treatment to be undertaken
and where it has been obtained some time in the past it should be repeated. In the US
some hospitals have their own rules on the appropriate timing of consent prior to
treatment although it is left up to the discretion of the individual surgeon when
working from his or her own office.
Immediately prior to making the initial incision or the application of forceps
and elevators to a tooth the operating surgeon must re-check the patients’ notes and
consent form to ensure that the correct procedure is about to be performed at the
correct site and on the correct patient! This is particularly important where the
operating surgeon is not the person who obtained the patients’ consent. Where
multiple teeth are to be extracted and in every case of extractions for orthodontic
purposes it is wise for the surgeon to clearly note the teeth to be extracted on a chart or
wall board that is legible from the chair/table side to act as a final check before
proceeding to extract each and every tooth.
It is imperative that there is adequate surgical access to and exposure of the
operative site. Incisions must enable the operator to fully and safely visualise the
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entire operative area with minimal need for tissue retraction and be sited with due
regard to surrounding vital structures and aesthetics. All other things being equal, an
incision 2 cm long will heal as well and as quickly as one 1 cm long. It thus makes
little sense to operate through a “key hole” as this will increase the risk of damage to
surrounding tissues as a result of traction and tearing.
It should be remembered, particularly by junior surgeons in training that it is
the operating surgeon who is ultimately responsible morally and legally for his or her
own actions. This is especially relevant in the hospital setting where not infrequently
the surgeon performing the operation is not the one who obtained the patients consent
(8).
On completion of the operation all extracted teeth, roots, instruments, needles
and swabs must be accounted for to ensure nothing has been left in the surgical
wound. Where a throat pack has been placed preoperatively in order to protect the
airway it is the surgeons responsibility to ensure that this has been removed, to
directly inform the anaesthetist that he or she has done so and to ensure that it has
been recorded in the patients operation notes. Failure to follow this protocol will one
day result in a patient suffering a respiratory arrest shortly after extubation with
potentially fatal consequences.
Before discussing individual complications in more detail it is worth stating
that even in the best and most experienced of hands accidents will happen and
operations will go wrong. In these situations, having expedited all necessary measures
and treatment commensurate with the surgeons skill and experience, it is vital that
every detail is recorded in chronological order and dated in the patients’ case notes.
Once recorded, alterations to the original entries must not be made. The patient must
be fully informed of what has happened, why it happened and the steps that have and
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will be taken to remedy the situation. In all things “honesty is the best policy” and
many medicolegal claims can be averted by adopting this strategy.
PERIOPERATIVE COMPLICATIONS
Extraction Of The Wrong Tooth
Extraction of the wrong tooth is an avoidable error which can easily be
prevented by ensuring that proper identification of the patient and tooth to be
extracted is made (14). Teeth commonly extracted in error are upper canines instead
of upper first premolars, lower permanent premolars simultaneously with lower
deciduous molars and upper second molars instead of upper third molars. The latter is
particularly liable to occur if the upper third molar is partially erupted and difficult to
visualise. Being aware of the possibility of these errors and “counting out” the tooth to
be extracted will go some way to minimising their occurrence. A common source of
confusion is the correct identification of one of 2 molar teeth when the other molar is
missing or absent. Although a naming convention exists for just this situation, long
hand notation such as “the first standing lower right molar” instead of the lower right
7 or 47 may help avoid confusion where the third molar is erupted and the first molar
is absent. A similar situation occurs when only one of 2 unerupted and adjacent teeth
are to be extracted. Again, this is commonly requested as part of an orthodontic
treatment plan and as such should be avoided at all costs (Figures 2 & 3).
If the wrong tooth is extracted the surgeon should proceed with removing the
correct tooth unless the extractions are for orthodontic purpose when it may be better
to seek the advice of the patients’ orthodontist first. The tooth extracted in error,
particularly if it is otherwise healthy, should be immediately replaced in its socket. If
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mobile it should be held in place with a custom made vacuum-formed splint for
approximately 4 weeks (14). It is likely that it will subsequently require to be root
filled and if there is any doubt about its prognosis the advice of a consultant
restorative dentist should be sought .
Fractured And Damaged Teeth And Restorations
Teeth adjacent to the index tooth may be fractured, loosened in their sockets,
subluxed or even extracted by the injudicious application and use of elevators. This is
particularly likely to occur if the adjacent tooth rather than the inter-radicular bone is
used as a fulcrum for the elevator and the elevator is being used as a lever against the
adjacent tooth. Fracture of the distal root of the upper second molar during elevation
of an impacted upper third molar may occur following excessive use of force
consequent on inadequate bone removal.
Damage to adjacent tooth roots can occur during bone removal performed for
apicectomies and surgical extractions. Close inspection of the preoperative
radiographs and noting the long axis of the tooth to be operated on is vital if only the
bone overlying the index tooth is to be removed. Special care should be paid to
apicectomies on previously post-crowned teeth. Not uncommonly, the long axis of
the crown will be divergent from the long axis of the root. If this is not appreciated
preoperatively extensive bone removal in an area distant to the index root apex may be
performed and the wrong root apicected. Root apices may be very close together,
particularly in the mandibular and maxillary incisor regions. Close attention must be
paid to crown/root orientation when apicecting these teeth if collateral damage is to be
© S F Worrall 1998
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avoided. Frequently, a sinus will perforate the buccal plate acting as a guide to the
site of the root apex beneath it.
Opposing teeth and restorations may be damaged if excessive force is applied
to a tooth via forceps or elevators and the tooth suddenly “gives” resulting in the
instrument forcibly contacting teeth in the opposing jaw. Not uncommonly, the distal
box of a restoration or an overhanging ledge on an inlay or crown in a lower second
molar will be dislodged if the adjacent lower third molar is elevated against it. If
possible the restoration should be attended to by the patients’ dental surgeon before
the third molar is removed. If a restoration is dislodged it is vital that all debris is
thoroughly removed from the extraction socket and the tooth dressed with a temporary
restoration until such time as it can be made permanent.
Fracture of a tooth or root during exodontia is the commonest complication
encountered in minor oral surgery (3, 14). Poor extraction technique, in particular
using the wrong extraction forceps, applying the forceps too close to the amelocemental
junction and too far from the root apex and injudicious use of elevators are
undoubtedly the major causes of tooth/root fractures during exodontia. This
complication is thus inversely proportional to the experience of the operator. Indeed,
complications of all types following the surgical removal of impacted third molars
have been reported to be significantly higher when performed by less experienced
surgeons (15). There is thus a strong case to be made for suggesting that ambulatory
oral surgery operating lists should be performed by the most senior clinician available
if unnecessary complications and unplanned hospital admissions are to be avoided.
Simple exodontia involving forceps and elevators depends on the ability of the
index tooth to expand the bony tooth socket walls to facilitate its own delivery. If the
alveolar bone is too dense to allow sufficient expansion to occur or the tooth roots are
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too brittle to expand the bone failure is assured. In some cases the age, sex, racial
origin and physique of the patient may alert the surgeon to the possibility of a difficult
extraction although in community dwelling adults age is not a risk factor for
complications following simple extractions (16). Patients with a history of “difficult
extractions” often have non-vital and brittle teeth surrounded by dense unyielding
bone. These “glass in concrete” teeth are also better tackled via an elective
transalveolar approach. Even then the surgeon may have to use the bur to cut out
every last fragment of tooth root due to repeated fractures when elevators are applied.
If preoperative radiographs have not been taken the surgeon will be unaware of
the teeth that have grossly curved, divergent, dilacerated, hypercementosed or fused
roots. Attempting simple forceps extraction of such teeth will inevitably result in
failure to complete the procedure or severe collateral damage. Where these dental
conditions are diagnosed on a preoperative radiograph the surgeon will be forewarned
of the problem and can take appropriate measures to circumvent complications. For
the most part this will involve electing to remove the tooth via a transalveolar
approach following judicious removal of overlying buccal bone (Figure 4).
As a general rule all fractured roots should be removed as soon as they are
produced. However, it is important to realise that in some circumstances root removal
may do more harm than good, particularly if they are close to structures such as the
neurovascular canal, maxillary sinus and lingual plate of the mandible. Small apices,
especially if associated with a previously vital and uninfected root can be safely
retained (17). The advice of the Arabian physician Avicenna (A.D. 980-1037) “The
cure of a disease must never be worse than the disease itself ” is particularly relevant
here. If it is elected to leave a root in situ the patient should be informed and the
reasons for the decision documented in their case notes.
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Tooth Displacement
Instead of the tooth being delivered safely from its socket into the mouth it
may be displaced into any one of a number of potentially hazardous areas including:
• The maxillary sinus
• Tissue spaces
• Inferior dental canal
• Aerodigestive tract
The Maxillary Sinus
The apices of the upper premolars and molars are normally close to the floor of
the maxillary sinus. Uncontrolled upwards pressure from extraction forceps or
elevators may force a tooth into the sinus. This is particularly prone to occur with
conical single rooted premolars and the palatal roots of molars, especially when a
Coupland elevator is forcibly inserted up the periodontal ligament. If a tooth is
displaced into the sinus it is imperative that it is removed as soon as possible. If the
tooth cannot be readily visualised then radiographs of the area in 2 planes at 900 to
each other should be taken to locate it (Figures 5 & 6). The transalveolar route should
then be used and the tooth/root delivered into the mouth via inferiorly directed
pressure from a suitable elevator. If there is to be any appreciable delay in removal
broad spectrum antibiotics should be prescribed to minimise the risk of infection and
subsequent breakdown of the mucosal repair.
© S F Worrall 1998
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Tissue Spaces
It is usually the third molars that fall victim to displacement into adjacent
tissue spaces. Unerupted upper third molars in particular are at risk from this
complication but no tooth is immune. The majority of upper third molars have a
natural path of withdrawal that takes them posteriorly and inferiorly. When the tooth
is erupted this will usually ensure safe delivery into the mouth. However, when the
tooth is unerupted and a buccal mucoperiosteal flap has been elevated the tooth may
slip behind the maxillary tuberosity and into the pterygomaxillary space from where it
may migrate into the deep structures of the neck (Figure 7). To prevent this
potentially disastrous situation occurring it is imperative that an instrument is always
placed behind the upper third molar which is kept under direct vision at all times
during its extraction. The Laster retractor, inserted around the back of the tuberosity
is arguably the most useful instrument in this situation as not only does it physically
prevent the upper third molar being displaced posteriorly but it also forms a light
reflective guide channel for the elevator thus improving visibility and protecting the
soft tissues of the lip and commisure which are frequently injured during this
manoeuvre (Figure 8).
Lower teeth are less prone to displacement than uppers but they can be so
affected. Lingually placed lower third molars and their roots may occasionally be
pushed through a thin or absent lingual plate into the floor of the mouth or below the
mylohyoid from where they can migrate into the neck. Similarly, lingually placed
lower premolars, particularly when unerupted may be displaced into the lingual
tissues. The latter situation is prone to occur if these teeth are “tapped out lingually”
using a mallet and elevator. On occasions, direct upwards digital pressure below the
mandible will bring the displaced tooth or root into sight and facilitate its removal. As
© S F Worrall 1998
21
with displaced upper teeth it is vital that the position of the lost tooth or root is located
via radiographs before attempting extirpation unless it can be easily and directly
visualised immediately post-displacement for fear of exacerbating the situation.
Radiographs in 2 planes at 900 should be taken and a lower occlusal and OPT are the
radiographs of choice. If the situation cannot be rectified immediately the patient
should be placed on antibiotics and referred to a consultant oral & maxillofacial
surgeon for urgent assessment and treatment. It may be possible to remove the tooth or
root via a standard transalveolar approach but more often the floor of mouth or even
extraoral route will be required depending on its position.
Inferior Dental Canal
If lower molar roots are fractured during elevation and the decision is taken to
proceed with their removal it is important that they are lifted out of the socket rather
than displaced further into its depths by the incorrect use and application of elevators.
Over zealous use of the Cryer elevator in particular can gouge out the roof of the
inferior dental (ID) canal into which the root can be subsequently pushed. As in all
situations, adequate exposure and illumination so as to afford good surgical access is a
pre-requisite. A fine round bur should be used to remove a channel of bone adjacent
to the retained root sufficient to allow its elevation upwards out of the socket. If a
root fragment is displaced and not readily visualised radiographs in 2 plains should be
taken. Again a lower occlusal and OPT are the radiographs of choice. Once localised
judicious removal of the roof of the ID canal is undertaken until the retained fragment
is found. Thereafter a blunt instrument such as a curved Warwick James elevator can
be insinuated beneath the fragment which is carefully lifted off the neurovascular
bundle.
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Aerodigestive Tract
It is all to easy for an extracted tooth or dislodged fragment to be swallowed or
worse still inhaled. Teeth with single conical roots are sometimes ejected from their
sockets unexpectedly during exodontia and patients will occasionally move violently
just as a tooth is being delivered (especially if they are nervous and/or the depth of
analgesia is inadequate). In these circumstances the tooth may disappear over the
dorsum of the tongue into the pharynx upon which the patients gag reflex is activated
compounding the problem. This complication is more likely to occur if surgery is
performed with the patient supine and without adequate airway protection. Wherever
possible extractions and surgical procedures performed under local anaesthesia with or
without sedation in the dental chair should be executed with the patient placed at
about 600 to the horizontal. Any tooth or restoration fragments should be immediately
removed by the surgeon or the assistant. Where patients are to be treated under general
anaesthesia if the airway is not protected via an endotracheal tube or laryngeal mask
etc. the patient should be placed at about 600 and a well fitting pharyngeal pack placed
to protect the airway. In most circumstances this will consist of an opened out
surgical swab or a sponge laid across the back of the tongue to occlude the
oropharynx. Even when an endotracheal tube has been placed the airway is still at
risk and the pharynx should be occluded with a throat pack. Many anaesthetists use
ribbon gauze for this purpose which although adequate for the task can abrade the
delicate mucosal lining of the pharynx both on insertion and removal adding to the
postoperative discomfort. In contrast, 2 tampons inserted one either side of the
endotracheal tube ensure complete pharyngeal occlusion without traumatising the
mucosa. As mentioned previously, it is the surgeons responsibility to ensure that any
throat pack is removed on the completion of treatment.
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If a tooth is dislodged into the unprotected pharynx with any luck the patient
will swallow it and it will pass naturally in several days time. However, it may well
be inhaled, and due to the manner in which the trachea branches at the carina not
infrequently becomes lodged in the right main bronchus. This situation will usually
be greeted by violent fits of coughing but may be silent. If such a situation occurs or
the tooth cannot be immediately accounted for an urgent chest and abdominal x-ray
should be ordered. If the patient is being treated outside of a hospital environment
they should be immediately referred via telephone to the local accident and emergency
or oral & maxillofacial unit. If the tooth is seen to be lying in the lung the patient is
urgently referred to either a cardiothoracic surgeon or respiratory physician for
bronchoscopy. If the tooth is seen within the stomach the patient is reassured that all
should be well and is recalled for repeat abdominal x-ray in a weeks time. If the tooth
has failed to pass a general surgical opinion should be obtained as soon as possible.
Fractures And Dislocations
Extraction Sockets And Access Cavities
Minor and inconsequential fractures of the tooth socket and inter-radicular
bone occur frequently during exodontia. Provided that any bone chips are removed
from the wound little harm is done. It is important to ensure that the socket edges are
smoothed and no sharp spicules remain. Uneven and sharp alveolar ridges are a major
source of postoperative discomfort and severely compromise the patients’ ability to
wear a denture comfortably. One manoeuvre to be particularly deprecated is the
placement of the beaks of extraction forceps outside a tooth socket and then crushing
the enclosed bone in order to deliver a fractured and retained root fragment. This
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causes excessive damage to the bone and often mutilates the overlying mucosa. If
large pieces of devitalised alveolar bone or bone dust from rotary instruments are left
behind postoperative pain and infection is almost assured. Following transalveolar
surgery of any type it is vital that the operative area is thoroughly irrigated with
copious amounts of 0.9% saline. One should pay particular attention to the depths of
buccal mucoperiosteal flaps and the lingual aspect of lower third molar sockets if a
lingual flap has been elevated.
Alveolus
The same factors that predispose to fractured teeth also predispose to alveolar
fractures, namely poor extraction technique, malformed teeth and dense alveolar bone.
Upper canines and upper molars, especially in well built young males are particularly
prone to result in alveolar fracture. On rare occasions, large sections of buccal or
palatal bone may be avulsed with the offending tooth. Again, many cases can be
avoided by thorough preoperative clinical and X-ray examination and the avoidance of
forceps extractions in high risk teeth and patients.
Fractures of the maxillary tuberosity are a special sub-group of alveolar
fractures. Tuberosity fracture is prone to occur if elevators are used to extract fully
erupted upper third molars or excessive force is used during the forceps extraction of
lone standing upper molars. In the latter case, loss of neighbouring teeth frequently
results in marked alveolar bone loss with encroachment of the maxillary sinus floor
towards the alveolar crest. If preoperative radiographs suggest tuberosity fracture is
likely then an elective transalveolar approach should be used.
Where an alveolar fracture occurs, immediate management will depend on its
extent. Small avulsed fragments effectively confined to the extracted tooth socket
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require no special treatment although the postoperative alveolar form will not be ideal
and may compromise future prosthetic rehabilitation. Larger fragments still attached
to mucoperiosteum should ideally be replaced and the segment immobilised via arch
bars or a vacuum-formed splint for approximately 4 weeks. Following which the
offending tooth is extracted via an elective transalveolar approach. If a substantial
alveolar segment is avulsed and detached from the overlying mucoperiosteum it is
likely that it will not survive if replaced. Maxillary tuberosity fractures not
uncommonly fall into this category. The avulsed bone should be carefully released
from any remaining soft tissues using a periosteal elevator. A large oro-antral
communication is virtually inevitable in this situation. However, following the loss of
the bone there is usually sufficient soft tissue to allow for a tension free closure.
Sutures should be left in for at least 10 days and the patient prescribed a broad
spectrum antibiotic together with 0.5% ephedrine nasal drops and enjoined not to
blow his or her nose for 2 weeks for fear of causing the soft tissue closure to
breakdown. All surgeons who practice exodontia must be able to manage this
complication in the manner described on-site immediately the problem occurs.
Fractured Mandible
This is probably the most feared of all complications following minor oral
surgery and like the majority of them is largely preventable (Figure 9).
Close inspection of preoperative radiographs will demonstrate the
impediments to tooth delivery and facilitate the formation of a treatment plan designed
to overcome the problems. Judicious bone removal and tooth division followed by
controlled elevation will be successful in virtually all cases. Very rarely the tooth to
be removed may be situated in an area where the bone is extremely thin as a result of
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pathological loss or age changes. Even in this situation fracture is not inevitable
although it may be prudent to apply direct fixation to the jaw either internally or
externally to support the area in the early postoperative period. Patients should be
advised to consume a soft diet for several weeks and to return immediately if they
become aware of any abnormalities in the jaw. These patients should be treated in a
hospital environment with access to the necessary equipment should a fracture occur.
If a mandible is fractured unexpectedly and the patient is already under general
anaesthesia the surgeon should proceed directly to fixing the fracture and fully explain
the situation to the patient postoperatively. If the fracture occurs under local
anaesthesia and outside of a hospital environment the patient should be immediately
referred via telephone to the local oral & maxillofacial surgery unit for urgent
assessment and treatment.
Temporomandibular Joint Dislocation
It can be extremely uncomfortable for patients having a lower molar extracted
not because of pain at the surgical site but because of traction on the
temporomandibular joints (TMJ) consequent on the surgeon pushing down on the
tooth with the extraction forceps. It is important that the surgeon fully supports the
mandible during extractions in order to relieve stresses on the TMJ. Some patients
find even light pressure uncomfortable and in this situation placing a rubber bite prop
between the contralateral posterior teeth and asking them to gently bite on it will
usually allow the extraction to proceed to completion. Where extractions are
performed under general anaesthesia it is all too easy to forget the TMJ. On
completion of treatment immediately prior to removing the throat pack the surgeon
should manipulate the mandible into centric occlusion to ensure that it is not
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dislocated. If it is then the dislocation should be reduced before the anaesthetic is
reversed and the patient woken up.
Soft Tissue Damage
Mechanical Trauma
The rich blood supply to the head and neck region usually ensures that all but
the most abused and damaged tissues will eventually heal. However, it cannot be
stated too frequently that the key to minimising surgical complications is meticulous
preoperative planning and surgical technique. In particular, gentle handling and
respect for the oro-facial soft tissues is mandatory. This is particularly important
when making elective incisions around the face. Wherever possible incisions should
be placed in the lines of election which are at right angles to the direction of the
resultant action of the underlying muscles of facial expression (18). Gentle handling
of the soft tissues specifically avoiding crushing and tearing the wound margins and
approximating the skin edges without tension is vital to success (“tight enough today -
too tight tomorrow”). Patients with a previous history of hypertrophic or keloid scar
formation should be treated by surgeons with considerable expertise in facial soft
tissue surgery.
One of the most disturbing sites to see on a postoperative ward round is the
patient who has excoriated and swollen lips and commisures due to careless tissue
retraction. This complication which is more likely to occur under general anaesthesia
than local anaesthesia displays an unacceptably casual attitude on the part of the
surgeon for the care of his or her patient. Copious amounts of vaseline or
moisturising cream should be applied to the lips to lubricate them preoperatively and
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repeated throughout the procedure. Highly polished instruments should be used and
the commisures protected with a gauze swab and cheek retractor (Figure 10). The
commonest scenario leading to damage to the lips and commisures is when they are
trapped between a Howarth’s periosteal elevator used as a flap retractor and the neck
of the elevator being used to extract an upper third molar, especially if the extraction
is difficult because of poor visibility and surgical access. It is all too easy to get
carried away with the extraction and neglect the soft tissues. The Laster flap retractor
provides unparalleled protection in this situation and is highly recommended.
Lacerations to the soft tissues can be caused by careless handling of scalpels,
elevators, forceps scissors and sutures. In fact any surgical instrument may cause
collateral damage if the surgeon loses concentration. Eye protection must always be
used when treating patients supine. It is appropriate at this point to condemn the
practice of the single handed operator who, in order to facilitate access to the mouth
inserts one end of a cheek retractor in the patients’ commisure and the other end
through the waist tie on the surgical gown. This is an extremely dangerous technique
which can easily lead to severe damage to the patients’ soft tissues if the operator
should slip backwards. A not uncommon occurrence!
Thermal Trauma
While all instruments should be autoclave sterilised wherever possible it is
vital to ensure that they are cool before coming into contact with the patient. Surgical
handpieces that are not serviced regularly and properly maintained are prone to
bearing failure. This will cause the handpiece to overheat in normal use. Especially if
old burs are used in an attempt to save money and excess pressure is applied to the
blunt bur because it cuts inefficiently. The hot handpiece then comes into contact
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with the patients’ soft tissues resulting in a deep burn. This is an indefensible disaster
and the cosmetic results can be truly appalling. If a surgical handpiece is running hot
it should be immediately discarded and sent for repair or condemned. A note to this
effect should be recorded in the operating theatre equipment log and the surgeon
should refuse to use it. If a replacement instrument cannot be provided and there is no
other safe way of completing the operation then the procedure should be abandoned
and the patient informed of the reason why. If a surgeon injures a patient with an
instrument that is known to be defective then he or she will only have themselves to
blame when they are sued for negligence.
Poor vigilance while using an electrical cautery or laser is another indefensible
cause of damage to surrounding soft tissues. When these instruments are in use, nonconducting
and non-reflective retractors should be used and in the case of lasers all
surrounding areas should be protected by wet swabs. Extreme care should be used
when using monopolar cautery to coagulate a blood vessel via a non-insulated pair of
tissue forceps in case they should come into contact with the surrounding soft tissues.
Nerves
The terminal branches of the trigeminal and facial nerves are the ones
most at risk from accidental damage during minor oral surgical procedures. The
inferior dental nerve is at risk of damage during removal of lower third molars, during
apicectomy of lower premolar and molar teeth, the placement of intraoral implants
and soft tissue surgery around the mental foramen, especially in the elderly where the
mental nerve may lie at or close to the alveolar crest. The lingual nerve is at risk
during the surgical removal of lower third molars the placement of intraoral implants
and incisions in the floor of the mouth for the removal of submandibular duct calculi
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and biopsies etc. Both nerves may be damaged by inadvertent direct nerve puncture
while administering an inferior alveolar nerve block. Less frequently documented is
damage to the infraorbital, buccal and incisive nerves. Mention has already been
made about the risks to the facial nerve from facial skin incisions etc.
The incidence of transient inferior alveolar nerve damage following lower
third molar removal varies between 1.3% (19) and 7.8% (20). Between 0.5% and 1%
of all lower third molar extractions results in permanent damage to the inferior
alveolar nerve (21). Following lower third molar extraction the incidence of
permanent lingual nerve sensory disturbance necessitating nerve repair lies between
0.3% and 0.8% (22). The health, social and financial impact to the patient of these
and other postoperative sequelae are frequently underestimated by clinicians (23). It
is mandatory that patients are fully warned about these possible complications
preoperatively. A few patients when so warned will decline their consent to undergo
surgery.
Potential damage to the inferior dental nerve during third molar extraction can
be anticipated in most circumstances by thorough examination of a high quality
preoperative radiograph of the area. Narrowing, loss of definition or acute change in
direction of the neurovascular canal in the immediate vicinity of the lower third molar
roots is highly suspicious of root notching or actual perforation by the neurovascular
bundle (Figure 11). In this situation, unless the tooth is symptomatic or there is an
exceptionally good reason for its removal it should be left in situ. If removal is
indicated then a transalveolar approach with wide access to the surgical field and root
sectioning should be employed. With careful handling the root can be divided so as to
free the entrapped neurovascular bundle (Figure 12).
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Forcible elevation of a deeply impacted lower third molar, particularly one
with a long mesial root is clumsy and can crush the contents of the neurovascular
canal. This is symptomatic of hasty and ill planned surgery. It is far better and safer
to section deeply mesioangular impacted teeth both horizontally and vertically and
remove the crown and individual roots separately.
Transient labial paraesthesia following lower premolar/molar apicectomies is
common as a result of mental nerve traction but permanent damage can and should be
avoided. Broadly based 3 sided mucoperiosteal flaps carefully elevated from the bone
afford excellent surgical access. Semi-lunar incisions should never be employed in
this area. The mental foramen and the emerging mental nerve must always be
identified and protected with a highly polished blunt flap retractor. Bone over the
apices of the tooth to be apicected is removed carefully and under constant direct
vision. In the case of lower molars it is safest to section the root near its midpoint
rather than the apical third as this will take the bur away from the neurovascular canal
and also make subsequent amalgam placement easier.
The lingual nerve not uncommonly lies superficially at the alveolar crest in the
retromolar triangle. Careless mucosal incisions in this region can easily sever the
nerve before any flaps are raised or bone is removed. The distal incision must always
be angled laterally to take it away from the lingual aspect of the ramus. Standard
teaching is that the incision should be taken up the external oblique ridge. It is
important that this incision is kept as short as possible in order to avoid severing the
buccal nerve as it crosses the anterior surface of the mandibular ramus in this area
(24). Likewise, avoidance of a buccal relieving incision by the use of an envelope flap
will minimise accidental damage to the buccal nerve in the sulcus while affording
excellent surgical access (Figures 13 & 14).
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The course of the lingual nerve may be very variable and in 17.6% of cases it
may lie at or above the level of the alveolar crest (25). Incisions in the floor of the
mouth must always be placed with due regard to the direction and level of the lingual
nerve. In particular, dochotomy of the submandibular duct to release a calculus must
be done with extreme care as occasionally fibrosis around the stricture will have
pulled the underlying lingual nerve upwards placing it at risk from an incision over the
duct. Similarly, sutures placed around the duct to prevent distal migration of the
calculus can easily damage the lingual nerve if they are placed to deeply in the floor of
the mouth.
Debate over how to protect the lingual nerve from damage during lower third
molar removal has raged for many years. There is good evidence to show that rather
than affording protection to the nerve and reducing lingual nerve damage, the
placement of the traditional Howarth’s periosteal elevator actually increases the
frequency of nerve trauma (Figure 15). Robinson et al (22) have demonstrated a
highly significant reduction in the incidence of temporary lingual paraesthesia when
lower third molars were removed without placing a Howarth’s down the lingual side
of the mandible compared to when a Howarth’s was used. This technique was not
associated with an increased incidence of permanent lingual nerve problems. There
will undoubtedly be occasions where lingual flap retraction followed by the careful
and correct placement of an instrument to protect the lingual nerve is necessary in
order to accurately and safely visualise a particular lower third molar. However,
avoidance of the routine use of traditional lingual nerve protection via a Howarth’s is
to be recommended wherever possible.
Intraoral implants, particularly mandibular endosseous implants are emerging
as yet another cause of litigation resulting from iatrogenic nerve damage (26). Poor
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preoperative planning and imaging together with the careless siting of endosseous
implants may damage the inferior alveolar nerve either within the mandibular canal or
after its exit from the mental foramen. The prevalence of altered inferior alveolar
nerve sensation following the placement of mandibular endosseous implants has been
reported to be as high as 36% of which 23% of cases were transient and 13% of cases
were persistent at 6 months or more post implant placement (26). Although
uncommon, transient lingual nerve paraesthesia has also been reported where
mandibular endosseous implants have perforated the lingual cortical plate (27).
Inferior alveolar nerve repositioning to facilitate the placement of endosseous
implants posterior to the mental foramen is associated with a very high incidence of
temporary inferior alveolar nerve damage. In one series inferior alveolar neurosensory
dysfunction was present in 70% of patients at 1 week before falling to 20% at 6
months and 0% at 1 year postoperatively (28). However, the technique enables the
placement of more and longer implants resulting in increased prosthesis strength and
stability and has a lower permanent dysaesthesia rate than when a non-transposed
nerve has been accidentally damaged by drilling or implant placement (29). If such a
technique is to be used it is vital that the patient is fully informed about the possibility
of temporary and permanent inferior alveolar nerve paraesthesia.
The raising of full palatal flaps to gain access to impacted canines or
supernumerary teeth can damage the incisive nerves as they exit the nasopalatine
foramen. If at all possible the nasopalatine neurovascular bundle should be preserved
intact as division of the nerves produces unpleasant premaxillary mucosal paraesthesia
which may result in accidental thermal trauma to the premaxillary mucosa from hot
food and beverages.
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The infraorbital nerve is not commonly involved in procedures typically
classified as minor oral surgery. However, it may be damaged by careless retraction
of buccal flaps during upper incisor or canine apicectomies. It is also at risk from
direct damage from infraorbital nerve local anaesthetic blocks. Gentle tissue handling
and thorough appreciation of the local anatomy should prevent this complication
arising.
Blood Vessels
Bleeding from severed vessels is inevitable and if excessive should be
controlled by ligation or electro-cautery. If troublesome bleeding occurs from an
intrabony vessel this can usually be arrested by crushing the surrounding bone walls
with the tips of a curved haemostat or with small amounts of sterile bone wax.
Bleeding from the pterygoid plexus can be worrying but will usually respond to direct
pressure applied via a gauze swab. Occasionally profuse bleeding will be encountered
from a severed inferior alveolar artery. This may occur because of inadequate
preoperative planning, injudicious use of an elevator in the depths of the socket or
cutting too close to the neurovascular canal while removing bone or sectioning a
tooth. It is vital that adequate suction is always available should this event occur. The
socket is packed under pressure with ribbon gauze which invariably will control the
situation. This should be left undisturbed for 15 minutes and then slowly removed. If
all bleeding has ceased the socket should be left open for a further 15 minutes before
primary closure is undertaken in case a re-bleed occurs shortly after pack removal. If
bleeding recurs the socket should be packed with ribbon gauze soaked with BIPP
(Bismuth Subnitrate Paraform Paste BPC) and left in situ for 24 hours.
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Very occasionally, a tooth socket may be involved with an arterio-venous
malformation. Clinical clues to this possibility may be associated cutaneous
haemangiomata, marked perioperative bleeding from around the tooth or a patient
with the Sturge-Weber syndrome. The surgeon should be very wary if an otherwise
healthy tooth becomes mobile, especially if it is a permanent tooth in a child as it may
be being pushed out of the socket by an arterio-venous malformation. As always,
thorough examination of preoperative radiographs should alert the surgeon to the
presence of any local abnormalities (Figure 1). Any suspicious cases should be
referred immediately to a consultant oral & maxillofacial surgeon who can arrange for
CT scans and angiograms to be performed if appropriate. If torrential bleeding occurs
when a tooth is extracted the tooth should be replaced in the socket and the patient
should be instructed to bite firmly together as this will provide the closest fitting
socket plug available. Otherwise gauze packing should be used. If the patient is not
already in hospital an ambulance should be summoned and immediate transfer to the
nearest specialist oral & maxillofacial surgery unit arranged.
It is beyond the scope of this chapter to fully discuss the management of
patients taking oral anticoagulants. Suffice it to say that if a patients’ INR
(International Normalised Ratio) is greater than 2.0 minor oral surgery may result in
persistent bleeding. Irrigating the operative site with 10ml of a 4.8% solution of
tranexamic acid followed by an 8 hourly 2 minute mouthrinse for 7 days with 10ml of
the solution has been shown to be highly effective in reducing postoperative bleeding
in patients with INR’s between 2.1 and 4.0 without having to modify their oral
anticoagulation dosage (30). However, such patients should be referred to a consultant
oral & maxillofacial surgeon for treatment as in some cases they will need to be
admitted to hospital and heparinised prior to stopping their warfarin before surgery
© S F Worrall 1998
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can be safely undertaken. If the INR is less than 2.0 simple extractions with full local
heamostatic control should not be problematical. Inferior alveolar nerve blocks should
not be used in patients who are anticoagulated.
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Broken Instruments
Modern instruments are manufactured to high standards and are unlikely to fail
if they are used correctly and properly maintained. Suture needles, hypodermic
needles and surgical burs are the items that most frequently fail in use.
Suture needles are probably the commonest items to be broken during minor
oral surgery. Careless handling and faulty technique probably account for the
overwhelming majority of breakages. In order to minimise bending stresses on the
suture needle the surgeon should always select a needle of the appropriate gauge.
Attempting to force thin needles through thick and tough tissues will inevitably result
in needle fracture. The suture needle should be grasped in the middle of its concavity
by the tips of the needle holders and rotated not pushed through the tissues. Choice of
needle holder is largely a matter of personal preference but serrated instruments such
as artery forceps must never be used as needle holders. If the suture needle becomes
bent it should be discarded, the surgeon must never attempt to straighten it because if
the needle doesn’t fracture immediately it is liable to do so when next inserted into the
tissues. Suture needles are particularly prone to being damaged when placing
interdental sutures as they often engage bone or tooth rather than passing cleanly in
between the teeth.
A new disposable hypodermic needle should be used for each patient and
should never be intentionally bent or grasped with forceps prior to use. Breakage is
uncommon but when it does occur is usually due to either a sudden violent movement
by the patient, faulty technique or a structural fault in the needle itself during either an
inferior alveolar or posterior superior alveolar nerve block (4).
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All burs should be clean, sharp and straight. Applying excessive force to a
blunt, worn bur generates excessive heat in the substance being drilled, damages the
handpiece bearings hastening their failure and increases the likelihood of bur fracture.
As soon as the surgeon detects that the bur has lost its edge it should be discarded and
replaced with a new one.
As a general rule all fragments of broken instruments should be removed
immediately before they have time to migrate deeper into the tissues. Whenever
administering a local anaesthetic injection there should always be a pair of artery
forceps readily available in case the needle should break. If the broken end projects
into the mouth it is easily grasped with the forceps and removed. Likewise broken
suture needles and burs are best retrieved with fine artery forceps immediately on
fracture. If the fragment cannot be found radiographs in 2 planes at 900 should be
taken of the operative area to locate it. At this point a decision will need to be made
as to whether to remove the fragment or leave it in situ depending on its size and site.
Small fragments lying subperiostealy can be safely left as they are unlikely to migrate
and cause problems (4). If the decision is taken to remove the fragment the operative
approach will depend on where it is located and a thorough knowledge of the local
anatomy is essential if further complications are to be avoided. It should be
remembered that small fine foreign bodies can be extremely difficult to locate and that
blind exploration of tissue spaces is wont to displace them deeper. The use of image
intensification can be very helpful in this situation.
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POSTOPERATIVE COMPLICATIONS
Pain And Swelling
Apprehension over the severity and extent of postoperative pain and swelling
is extremely common in patients about to undergo minor oral surgery, particularly
third molar removal. Instituting active measures to maximise any reduction in
postoperative pain and swelling is an integral part of high quality patient care.
The efficacy of systemic analgesics is greatly enhanced if patients are given
regional local anaesthetic blocks or infiltrations perioperatively (31). Inferior dental
nerve blocks administered perioperatively for patients undergoing lower third molar
removal under general anaesthesia improves pain control in the early postoperative
period. However, it is vital to warn patients about the possibility of accidental injury
from biting or thermal burns from hot food and beverages whenever local anaesthetics
are administered.
Some degree of postoperative swelling following minor oral surgery is
inevitable although its extent is highly variable and unpredictable. This variation is
due to patients having widely different inflammatory responses to similar surgical
insults independent of operator variability. Postoperative pain, and patients ability to
tolerate it is directly correlated with the degree of postoperative swelling present (32).
Llewelyn et al (33) using magnetic resonance imaging (MRI) have shown that
following the removal of third molar teeth patients sustain a mean swelling of almost
1cm on the first postoperative day.
Postoperative oedema can be lessened by careful tissue handling and its extent
is dependent on the skill of the surgeon (34) In particular, retractors and elevators
must be used with care. Rotating surgical drills must never be allowed to “snag” the
© S F Worrall 1998
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surrounding soft tissues or abrade the buccal and labial mucosa and the drill tip must
be constantly cooled to ensure that the bone is never allowed to overheat. Standard air
turbine dental handpieces generate very high vent pressures. They must never be used
for bone removal or tooth section as the forward facing air jet can lead to massive
emphysema of the surrounding soft tissues with the risk of subsequent pain, swelling,
infection and tissue necrosis (Figure 16).
Extraction sockets and pathological cavities must be irrigated with copious
amounts of 0.9% saline to remove all bone fragments and debris. Failure to accurately
place a retrograde root filling in the root apex and failure to remove excess amalgam
from the surgical cavity not only produces an embarrassing “shot gun” postoperative
radiograph but also predisposes to surgical failure from chronic pain and infection. To
prevent this error the surgical cavity should be occluded with a strip of ribbon gauze
so that only the root apex access cavity is visible. Small volumes of amalgam should
then be carefully introduced and condensed immediately. This procedure can be
greatly facilitated by using specially designed amalgam carriers and magnifying
loupes. On completion the gauze is removed and the cavity thoroughly irrigated and
all traces of stray amalgam removed.
Pharmacological treatments can be used as an adjunct to meticulous surgery to
reduce postoperative oedema. The combination of systemic steroids and non-steroidal
anti-inflammatory drugs has been shown to produce marked reduction in
postoperative pain and swelling following third molar removal (35). The
administration of 40 mg methylprednisolone intravenously immediately prior to
surgery has been shown to significantly reduce early postoperative oedema and pain
and improve patient satisfaction following the removal of impacted lower third molars
(36). No increased morbidity from infection or delayed healing was noted.
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Although the hypothalamic-pituitary-adrenal (HPA) axis is acutely depressed
following a single intravenous dose of 8mg of dexamethasone the HPA response has
normalised by 7 days postoperatively (37). It is the authors practice to administer 8mg
dexamethasone (equivalent to 42.7 mg methylprednisolone (British National
Formulary)) intravenously immediately prior to surgery and 400-600 mg ibuprofen 8
hourly postoperatively for all procedures requiring bone removal unless
contraindicated for medical reasons.
Infection
If infected and abscessed teeth and roots can be extracted easily using forceps
or elevators, and providing a local anaesthetic injection is not instilled directly into an
area of inflammation or acute infection their loss will hasten the resolution of
symptoms by removing the source of infection. The use of regional local anaesthetic
blocks in these circumstances can be useful although even then surgical analgesia may
not be achievable.
As a general rule the transalveolar approach for the removal of teeth and roots
is contraindicated in the presence of acute infection lest the infection be spread to
deeper structures. This is particular so when lower third molars are associated with
acute pericoronitis. Injudicious removal can result in a parapharyngeal space infection
and upper airway obstruction. Wherever possible extraction should be deferred until
the tooth has been infection free for 2-3 weeks.
In the normal course of events and in the absence of pre-existing infection
postoperative pain and swelling will be on the wane after 48 hours or so. However,
should the operative site become infected pain, swelling and trismus fail to resolve
© S F Worrall 1998
42
and usually increase around this time. The infection rate following minor oral surgical
procedures is low, and in a series of 6,713 third molar extractions was only 3.5% (38).
Dry Socket
Dry socket, also variously termed alveolar osteitis, fibrinolytic alveolitis and
alveolitis sicca dolorosa is a well recognised complication of exodontia (4). It is
characterised by increasingly severe pain which usually starts on the second or third
post-operative day in and around the extraction site lasting for between 10 and 40
days. The normal post-extraction blood clot is lost from the tooth socket the bony
walls of which are denuded and exquisitely sensitive to gentle probing. Halitosis is
invariably present. There is great variation in reported incidence rates (1% - 65%)
between series usually due to inconsistency in diagnostic criteria, variation in
antimicrobial prophylaxis and study sample heterogeneity. The true incidence rate
probably lies somewhere between 3% and 20% of all extractions.
The aetiology is multifactorial but essentially it results from lysis of the normal
post-extraction blood clot. Increased concentrations of both direct and indirect
plasminogen activators result in an increased local concentration of plasmin and
subsequently an enhanced degradation of fibrin to soluble fragments with clot
disintegration and loss. Direct plasminogen activators are released from damaged
alveolar bone cells. Bacterial pyrogens and oestrogens, particularly those found in oral
contraceptives are potent indirect plasminogen activators. It is thus hypothesised that
a dry socket results from a complex interaction between surgical trauma, local
bacterial infection and various systemic factors (39).
Dry socket is a painful, debilitating condition that results in considerable
suffering, inconvenience and loss of productivity to the patient. It is also a costly and
© S F Worrall 1998
43
time consuming condition for the attending clinician as 45% of patients will require at
least 4 additional post-operative visits (40).
Several factors have been found to be associated with an increased risk of
developing a dry socket (38, 39, 40, 41, 42):
• Extraction of mandibular rather than maxillary teeth
• Extraction of third molars, especially impacted lower third molars
• Singleton extractions
• “Traumatic” and unduly difficult extractions
• Female sex especially if concurrently using oral contraception
• Patient aged between 20 and 40 years
• Poor oral hygiene and plaque control
• Active or recent history of acute ulcerative gingivitis or pericoronitis
• Smoking, especially if >20cigarettes/day
• Increased bone density either locally or generally such as Paget’s disease
• Previous history of dry socket(s) following extractions
• Inexperienced surgeon
Clinical application of the above data will minimise the incidence of dry
socket. If appropriate, wherever possible oral hygiene measures to reduce plaque
levels to a minimum should be instituted and all patients should be given a 0.12%
chlorhexidine mouth rinse immediately preoperatively. Lower third molar extractions
should be avoided in the presence of active pericoronitis or acute ulcerative gingivitis.
For difficult full or partial bony lower third molar impactions where bone needs to be
removed, for immunocompromised patients and for patients with a history or previous
pericoronitis or acute ulcerative gingivitis, appropriate antibiotic prophylaxis should
© S F Worrall 1998
44
be prescribed. Patients who smoke should be enjoined to cease the habit preoperatively
and for at least 2 weeks postoperatively while the extraction sockets heal.
Wherever possible, for female patients using oral contraception, extractions should be
performed during days 23 through 28 of the tablet cycle.
All extractions should be completed with the minimum amount of trauma, the
maximum amount of care and as rapidly as possible commensurate with their degree
of difficulty and the experience of the operator. On completion of the procedure the
operative site should be irrigated with copious amounts of sterile saline followed by
15 ml of 0.12% chlorhexidine. Patients should be advised to avoid vigorous mouth
rinsing in the immediate post-operative period but to use gentle tooth brushing and
0.12% chlorhexidine mouth rinses for the following 7 days. All patients should be
advised to return to the surgery/hospital immediately if they develop increasing pain
or a bad taste.
In cases of established dry socket patients should be managed along the
following lines: The affected socket(s) should be gently irrigated with warmed 0.12%
chlorhexidine and all debris dislodged and aspirated. In extremely painful cases local
anaesthesia may be required before socket irrigation can be performed. Wherever
possible regional nerve blocks should be employed. The socket should be lightly
packed with a dressing that contains an obtundent for pain relief and a non-irritant
antiseptic to inhibit bacterial and fungal growth. The dressing should prevent reaccumulation
of food debris and protect the exposed bone from irritation. Ideally, the
dressing should slowly dissolve without the need for its removal and should not excite
a host inflammatory or foreign body response. Numerous commercial agents are
available which fulfil these requirements to a greater or lesser extent. Alternatively,
sterile ¼ inch ribbon gauze impregnated with BIPP (Bismuth Iodoform Subnitrite
© S F Worrall 1998
45
Paste) can be used although it requires subsequent manual removal by the attending
clinician. Providing there are no signs of systemic infection antibiotics are not
routinely required. Suitable and effective systemic analgesics should be prescribed and
the patients’ progress should be reviewed the following day and frequently thereafter
until full healing has occurred. Hospitalisation is rarely required.
For patients about to undergo surgical removal of full or partial bony impacted
third molars the use of systemic antibiotics confers a significant reduction in
postoperative infection rates (38). If prophylactic antibiotics are to be beneficial they
need to be given preoperatively and no more than 2 hours prior to the commencement
of surgery (43). There is no point in prescribing postoperative oral antibiotics for
clean contaminated procedures (the majority of minor oral surgery) if preoperative
systemic antibiotics have been given as they will confer no added benefit. If
preoperative systemic antibiotics have not been given, prescribing postoperative oral
antibiotics confers no benefit at all. The authors policy is not to use antibiotics for
clean contaminated soft tissue surgery, simple extractions or soft tissue third molar
impactions. For procedures involving bone removal such as third molars and
apicectomies and providing there are no medical or pharmacological contraindications
a single intravenous dose of 1.2g Co-Amoxyclav is given immediately prior to surgery
commencing. Chlorhexidine 0.12% mouthwashes 6 hourly are prescribed for 1 week
postoperatively but oral antibiotics are not given.
Osteoradionecrosis
Patients with head and neck cancer who are treated by radiotherapy either as
sole modality or as part of a multi-modality treatment plan are at risk of developing
osteoradionecrosis in bone in the treated area. Osteoradionecrosis results from
© S F Worrall 1998
46
radiation induced tissue hypoxia, hypocellularity and hypovascularity (44, 45).
Osteoblasts and osteoclasts within the radiotherapised bone may be lethally damaged
by the ionising radiation although they are still able to perform their resting vegetative
functions (44). Because of the extremely slow bone cell turnover rate this causes few
problems until the cells are stimulated to divide. The most common stimulus to
divide is provided by tooth extraction which then commonly results in massive bone
destruction and secondary bacterial infection. Osteoradionecrosis is an extremely
painful, debilitating and indolent disease that makes patients’ lives an utter misery.
This complication must be avoided at all costs. The most effective way of preventing
osteoradionecrosis is to ensure that all patients who are to receive medical irradiation
to the head and neck have a thorough oral examination including OPT screening. For
head and neck cancer patients this should occur in the context of a multi-disciplinary
head and neck oncology clinic. Any teeth in the proposed treatment area of doubtful
prognosis by virtue of decay or periodontal disease should be scheduled for extraction.
If the patient is to undergo surgical resection prior to radiotherapy the ideal time to
extract the teeth is during the pre-surgical examination under anaesthetic (EUA).
Otherwise the teeth should be extracted under local anaesthetic 1 to 2 weeks prior to
commencing radiotherapy.
No matter how careful and thorough the work-up there will always be
circumstances where a patient will require extractions post-radiotherapy. Such
extractions should be performed by the oral & maxillofacial surgeon attending the
oncology clinic and not delegated to the patients’ general dental practitioner. Broad
spectrum antibiotics are administered intravenously immediately preoperatively along
with 0.12% chlorhexidine mouthwashes and the gingival margins of the teeth to be
extracted swabbed with iodine solution. Extractions are performed in the most
© S F Worrall 1998
47
atraumatic way possible which may involve the elective use of a transalveolar
approach and bone removal depending on the finding on the preoperative radiograph.
Postoperative antibiotics and chlorhexidine mouthwashes are commenced and
continued until the sockets are healed. There is extensive evidence that established
osteoradionecrosis is best managed by hyperbaric oxygen therapy and subsequent
surgical debridement (46). In patients at high risk of developing osteoradionecrosis it
may also be prudent to use a pre-extraction hyperbaric oxygen therapy regime
provided that this would not adversely delay starting primary treatment for the patients
head and neck cancer.
“Learning without thought is labour lost; thought without learning is perilous”
(Confucius 550 - c 478 BC)
© S F Worrall 1998
48
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