Complications in oral surgery

 Complications in oral surgery

INTRODUCTION

Oral surgical procedures can be complicated by various untoward incidents during the surgery or in the recovery

phase. The best way in the management of complications is prevention.

CLASSIFICATION

The complications can be classified as follows-

1. Intra-operative complications-

a) Local complications

b) Systemic complications.

2. Post-operative complications-

a) Immediate

Local complications

Systemic complications.

b) Delayed

Local complications

Systemic complications.

Intra-operative complications

a) Haemorrhage. 

b) Nerve injury. 

c) Oro-antral perforation and fistula formation. 

d) Oro-nasal fistula. 

e) Fracture of the bone or tooth. 

f) TMJ dislocation. 

g) Displacement of tooth into spaces. 

h)Fracture of maxillary tuberosity. 

i) Damage to the adjoining dental structures. 

j) Angio-neurotic oedema. 

k) Emphysema

Post-operative complications

a)Infection

b) Trismus.

c) Dry socket.

d) Swelling and pain.

e) Hematoma formation.

f) Ankylosis of TMJ.

g) Facial disfigurement.

h) Rejection of grafts.

i) Malunion, delayed union and non union.

j) Secondary haemorrhage.

k) Subacute bacterial endocarditis

m) Ecchymosis.

HAEMORRHAGE

Haemorrhage is the most common complication during the surgery and in post-operative phase. The cause of

abnormal bleeding can be mechanical or biochemical. All cases of surgery or extraction should be carefully evaluated for any bleeding disorder, history of hypertension, medication like anticoagulant and hepatic disorders.

The haemorrhage can be primary, intermediate or secondary haemorrhage,depending on the time factor.

Primary haemorrhage is the bleeding during the

operation.

The intermediate haemorrhage occurs within 24 hours after the operation.

The secondary haemorrhage may occur 24-48 hours after the surgery and is usually as a result of clot breaking down due to infection.

A biochemical haemorrhage is due to the absence of one or more blood factors required for normal clotting mechanism.

It is advisable to recommend the routine laboratory tests regarding assessment of bleeding during the

operation. A patient with a history of bleeding should be thoroughly investigated.

A patient with a history of bleeding disorder should be investigated for haemoglobin, bleeding and clotting time, clot retraction, red blood cell count, platelet count, white blood cell count and differential count, prothrombin time and index, liver function tests, blood grouping and cross matching etc.

Intra-operative haemorrhage from the bone can be controlled with bone wax or by crushing the bone with blunt instrument. Bleeding from soft tissues is controlled by pressure packs, electrocoagulation,catching and ligation of blood vessels as well as ligation of major vessels. Bleeding from the extraction socket can be controlled by pressure pack or by packing the socket with gelfoam or oxidised cellulose and suturing the soft tissue flaps over it.

A post-operative haemorrhage secondary in nature requires opening of the wound and use of pressure packs, ligation of vessels and resuturing of the wound.

An extraction socket can be covered by ing a softened impression compound the socket, allow it to harden and ask patient to bite over it.

Application of vasoconstrictor over the bleeding area is helpful only in locating the bleeding points as a result of vasoconstriction. Such points should be grasped with artery forceps and ligated because excessive use of vaso constrictor only allows the absorption of drug from the and subsequent hypertension followed by excessive haemorrhage again. wound

ECCHYMOSIS-

Ecchymosis produces facial discolouration ranging from bright red to deep bluish or purple in colour. It depends on the extent of surgical procedure and bleeding tendency of the patient.

If the surgical area is wide and a major surgery involving bone and soft tissues is carried out leaving minor ooze from bone and muscles, there are more chances of a minor a patient with show wider ecchymosis developing. Similarly, a minor surgical procedure in a patient with bleeding disorder may show wider ecchymotic areas.

The site at which the ecchymosis will appear at the surface depends upon the I course taken by the blood through the muscles and fascial planes. The common areas where post-operative ecchymosis is seen are circumorbital, sub- mandibular regions, lower lip, vestibule and floor of the mouth. It may extend into neck and thorax as well from maxillofacial region.

The management lies in immediate application of cold followed by application of heat once the ecchymosis has appeared. The discolouration is caused by breakdown of haemoglobin. The colour fades from deep purple, bluish black, bluish, greenish yellow and then back to normal. In case of large ecchymotic areas, it is advisable to give a cover of antibiotics alongwith application of proteolytic enzymes to help in break down of coagulated blood. On an average it takes 7-10 days for ecchymosis to disappear.

ORO-ANTRAL PERFORATION-

There is possibility of causing a large oro- antral perforation especially while extracting a maxillary premolar or molar. The proximity of the maxillary first molar and second premolar to the maxillary antrum is of great importance.

Causes-

These perforations are caused as a result of injudicious use of elevators and chisels for extracting the broken roots of the teeth. There is a possibility of pushing a root into the antrum with or without tearing the lining of the maxillary antrum.

Additionally, the oro-antral opening can be caused by removal of the floor of the sinus alongwith the extracted tooth, destruction of the sinus floor by chronic periapical infection against the maxillary teeth, by deep curettage of the extraction socket and injuring the lining of the sinus through it, rupturing the floor of the sinus while extracting an impacted maxillary third molar or enucleating a large maxillary cyst and fracturing a large segment of the alveolar process containing the floor of the antrum.

Diagnosis-

Whenever there is a doubt of making of an oro-antral opening, it is strictly advised against any probing through the socket. The patient may be asked regarding any escape of air into the antrum and the nasal cavity when the mouth is filled with air. The large bleeding openings result in escape of blood from the antrum through the nose when the former is full with blood. A fistula of long standing duration may present with escape of fluid from the oral cavity into the antrum and nasal cavity. There is associated salted watery discharge from the antrum into the oral cavity.

Management-

The management of oro-antral openings and fistulas can be divided into two phases immediate closure and closure of long standing fistulae.

Immediate closure is recommended in those cases which are clean and without any infection of the antrum. A very small opening normally repairs with organization of the blood clot that fills the extraction socket. A larger opening should always be closed by plastic repair. In case a root has been pushed up, a careful visual and radiological examination should be done to establish if the root is actually in the antrum or between the antral membrane and the bone.

The root in the sinus should always be removed prior to closure. The patient is asked to blow out the air with the nostrils closed and the oro-antral opening is carefully looked for the root. A suction tip with a small diameter can also be used at the mouth of the opening. Alternatively, a long piece of roll gauge is loosely packed into the antrum through the opening and pulled out in one stroke to bring the root out along. If these procedure fail, the muco-periosteal flap on the buccal side is raised to widen the opening and acess to the root is obtained for its removal.

Various other techniques like combination of buccal and palatal flap, use of tentalum gauze or gold foil or buccal pad of fat etc are used for plugging the oro - antral openings.

ORO-NASAL OPENING/ FISTULA

A communication established between oral cavity and nasal cavity is possible when there is perforation of palate due to variety of reasons. An accidental perforation with a straight elevator or chisel during the extraction of a premolar tooth can occur if the instrument slips onto the palate to perforate it there under tremendous amount of application of force. Oro-nasal communications are also seen following fractures of middle third facial skeleton involving the palate. There may be a midline split or fragmentation of the palate. Injudicious use of electric cautery over the palate can lead to necrosis and perforation. Removal of very large anterior cysts in maxilla may produce oro-nasal communication where the cyst has destroyed the bony floor of the nasal cavity with only soft tissue lining left in between .Residual oro-nasal fistulae are also seen following the repair of clefts of palate especially in wide and bilateral clefts Periapical infection, osteomyelitis leading to necrosis and gummatous stage of syphilis are also known to cause oro-nasal fistula.

Oro-nasal fistulae are seen as perforations in the roof of the oral cavity and communicate with nasal cavity. It results in a nasal twang in the voice. The water and food material can escape in to the nasal cavity. There is uncontrollable rhinitis and tonsillitis due to this problem.

Management

Management involves giving an acrylic plate to cover the fistula till such time surgery is undertaken. At times patient is so happy with this denture or acrylic plate covering the fistula that he refuses to go for surgery. Small fistulae of not very long standing duration can be treated by giving elliptical incision around the fistula on the oral side of much periosteum .

The flaps are everted and sutured in the midline in such a fashion that the knots are placed onto the nasal side. This becomes the nasal layer. The raw surface is now covered with muco periosteal flap mobilized from the palate and stitched in the midline. This becomes the oral layer thereby completing the double layer closure. The raw surface on the palate is left to granulate.

The large oro-nasal fistula is closed after excising the lining with the help of large sliding flap pedicled with greater palatine artery as is done in case of oro entral fistula with rotational palatal pedicle flap. It is difficult to obtain single layer closure for large fistula. Such fistulae are closed by using a tongue flap from the dorsum of the tongue. The nasal layer closure is obtained by using the oral side of palatal muco-periosteum as explained above. The tissue from the dorsum of the tongue is used to cover this layer and to be sutured with the palatal mucosa.

EMPHYSEMA

Emphysema is the presence of air in the interstitial connective tissue leading to a swelling. On palpation a typical crackling sound is noticed. The complication is rarely seen in oral and maxillofacial surgery practice. It can be seen following an injection of local anaesthetic in case the air from the syringe has not been removed prior to injection. Alternatively, emphysema is also seen following trauma especially injuries of the middle third facial skeleton leading to a tear in the periosteum over the antral region. When these patients try to cough or blow out, the air can access into the tissues from the nasal cavity and maxillary antrum through the tear in the periosteum.

The air in the fascial planes expands at the body temperature leading to massive swelling in the area. It can prove dangerous if this air is quickly absorbed into a vessel. This air is carried to the heart. Since air is compressible, the column of air gets compressed when the heart contracts and the column expands when the heart dilates. Such a phenomenon leads to circulatory failure with dangerous consequences. Whenever the air is collected in the tissues, it is advisable to permit the escape of trapped air by simply introducing a large gauge needle in the area.

SOFT TISSUE INJURIES

Injury to the soft tissues in and around the oral cavity is mainly attributed to negligence on the part of the surgeon and his team. The main cause of this problem is faulty instrumentation.

A negligent dentist may catch the buccal or lingual/palatal mucosa between the beaks of the extraction forceps while extracting the tooth. It produces a very painful wound because the mucosa is punched out. At times big mucosal tears are caused when an elevator slips out. In the deeper structures, it may cause haemorrhage or even a serious injury Catching of the lip between the handles of a forceps or compression of the lips during a very forceful retraction may lead to lip tear. These injuries can best be avoided by prevention alone. The mucosa around the tooth should be separated prior to extraction to facilitate the insertion of forceps under the mucosa. During elevation for extraction, it mandatory to keep finger guards to save the soft tissues from any trauma. A careful retraction during intraoral procedures is extremely important. The retractor should be blunt, non-traumatic and of appropriate size.

Should an injury occur to the soft tissues, there is abnormal bleeding encountered. It should be checked with pressing sponge over the area. In case of tear, a repair should immediately be carried out to restore the normal anatomy.

INJURIES TO TEETH BONE AND MAXILLARY TUBEROSITY ALVEOLAR

The intra-operative complications of extraction of teeth include extraction of wrong tooth, loosening of adjoining tooth, the fracture of tooth, fracture of filling in the adjacent tooth, fracture of the alveolar bone and maxillary tuberosity and loss of tooth into the adjoining areas. Majority of these complications are attributed to negligence, injudicious use of force, application of wrong instruments and improper illumination or retraction etc. Very small root pieces especially in the absence of infection should be left in place to avoid involvement of maxillary sinus and injury to inferior dental nerve.however, an infected root piece should be carefully removed.. Fracture, luxation of the adjoining tooth and fracture of filling in these teeth should be carefully judged and must be avoided by planning and carrying out surgical extraction.

Small pieces of alveolar bone or maxillary tuberosity if fractured, removed alongwith the tooth. However large pieces of alveolar bone that remains attached to the mucosa as well as may tuberosity should be placed back in position with or without the tooth in question. These large bony pieces are held in place with dental splints, wires, or by placing tight sutures only. These bones are easy taken back. The tooth in question can be removed surgically by open method alter four weeks.

FRACTURE THE MANDIBLE

Fractures of the mandible have taken place while carrying out difficult extractions especially when removing impacted mandibular third molar. This complication is due to injudicious use of elevators and the tremendous amount of force for elevating a tooth out of the socket. A dentist must be cautious against applying undue pressure far beyond the limit required to elevate a tooth.

For all such teeth the problem of fracture of mandible can be averted by undertaking an open extraction. The pre-extraction radiographs are a big help to assess if an open action is required or not. Excessive condensation of bone, unduly curved and bulbous roots, limited path of removal of the tooth and presence of associated bony pathology are some of the indications where an open extraction preferably by sectioning the tooth should be carried out.

Whenever an extensive destruction of bone due to any pathology is revealed in pre-extraction radiographs, the dentist must inform the patient of the possible facture during the extraction procedure. A careful planning should be done to avoid fracture in such cases as the management extremely difficult. A benign bony cavity can be filled with bony chips following the Immobilization of fractured fragments. A large defect may require autogenous bone transplant or other reconstructive measures after the treatment of pathology in the bone. Under no circumstances an oral and maxillofacial surgeon should go ahead with bone grafting procedures without confirming the nature and behaviour of the lesion.

BROKEN NEEDLES

Injection needles are broken into the tissues accidently especially if needles beyond 25 gauge are used. A faulty technique is more or less the cause of broken needle these days. It is mandatory for the dentist to check against rusted and blunt needles especially when needles are being reused after boiling. There is less incidence of fracture of needle in a setup where disposable needles are used. Sharp sterile needles for single use are available at very low cost these days. The following tips are important to avoid breakage of needle

Do not use old rusted needles of fine guage.

Never insert the needle into the tissues upto the hub because the junction between the needle and the hub is the weakest point and if the part of the needle is out of the tissues, it can easily be grasped with the hemostat in the event of breakage.

Always use sharp needles and elicit minimum pain to the patient to avoid jerks and muscular spasm.

Never change paths of needle in the deeper planes. Should it be required withdraw the syringe till a point of needle is under the mucosa and reinsert the needle in the new direction.

Never insert a fine needle against resistance.

In case a needle is broken and lost into the soft tissue, the patient should be told about it. These broken needles do not migrate to any great extent. The broken needle should be located by taking series of radiographs from different angles. It is advisable to insert another needle through the same route. Leave the needle in position by disconnecting the syringe. The suture may be passed around the hub through the cheek to maintain the position of the needle. The position of the broken needle is located in reference to the guide needle with the help of radiographs. Both antero-posterior view and lateral view are taken preferably in open mouth position.

The removal of the needle is undertaken under proper illumination of the field. Palpation of the area with finger. is strictly contraindicated as it may push the needle into deeper planes. After incising the mucosa the search for the needle in the tissues by blunt dissection alongside shaft of the guide needle is carried out. Once the needle is contacted it should be grasped with hemostat. The edge of the needle should be exposed and be grasped with another hemostat. The first hemostat is disengaged in order to remove the needle. along its long axis. The wound may be closed like any other surgical wound.

TOOTH DISPLACED IN THE SURGICAL SPACES

At times during extraction specially that of mandibular third molar, the same may get displaced into the spaces of the neck.

The possibilities are more it medial wall of the mandible (lingual plate of bone) has been destroyed due to infection or presence of a cyst. This can also has if the lingual bone is fractured and tooth is pushed medially during elevation. It is for this reason that a thumb or a finger gaurd on the lingual side of mandible should always be kept while elevating 3 rd molars. Maxillary 3rd molar can be pushed into the pterygomaxillary fossa under the soft tissue flap by a forceful elevation .A tooth can also be displaced into maxillary antrum.

A tooth displaced into submandibular, pterygomandibular parapharyngeal space can be removed through an intraoral approach. The position should be localized with the help of radiographs like PA view mandible. lateral view of the skull and mandible and lateral oblique view of mandible.Tomography and computerised tomography are of additional help.

The surgical procedure can be under taken under local or general anaesthesia. The tooth should always be palpated from below upwards after spraying oropharynx with local anaesthetic spray.The spaces in the neck can be approached by giving an incision on the anterior border of the ramus of the mandible just medial to internal oblique ridge. The tooth car reached with blunt dissection. It shoul fixed between the fingers over the mucosa before grasping with a hemostat. If precaution is not undertaken there chances of tooth being pushed deeper into the spaces.

NEURAL INJURIES

Injuries to the sensory nerves lead to complete or partial loss of sensation and numbness or tingling and burning sensation in the area whereas the motor neuron injuries result in paralysis of muscles. The most important source of these neurological problems is trauma. However, the neural problems are also associated with infection, swelling and lesions involving the higher tracts and centres.

The most common nerve involved in surgical trauma is the inferior dental nerve. It is injured during the removal of impacted mandibular molar as well as operation in the area of mental foramen. The result is numbness or tingling of the lower lip on the side affected. In majority of the cases when the severed ends are lying in close proximity in the inferior dental canal the regeneration of the injured nerve takes place. The lingual nerve can be injured during the removal of impacted mandibular third molar using lingual bone split technique, if a chisel slips to cut the unguarded nerve. Injury to the lingual nerve is also possible while removing stone from the duct of submandibular gland. In surgery of the palate, naso-palatine nerves are severed when anterior palatal flap is reflected for removal of a cyst, growth or impacted canine.