http://dx.doi.org/10.5272/jimab.2016223.1202 Journal of IMAB Journal of IMAB - Annual Proceeding (Scientific Papers) 2016, vol. 22, issue 3 ISSN: 1312-773X http://www.journal-imab-bg.org COMPLICATIONS AFTER EXTRACTION OF IMPACTED THIRD MOLARS- LITERATURE REVIEW

Elitsa G. Deliverska, Milena Petkova. Department of Oral and Maxillofacial surgery, Faculty of Dental medicine, Medical University –Sofia, Bulgaria

ABSTRACT cations. Most of the complications are associated with a Third surgery is the most common procedure greater degree of impaction. Teeth classified as having IC, performed by oral and maxillofacial surgeons worldwide. IIC and IIIC impaction have more complications than teeth This article addresses the incidence of specific complications classified as having B or A impaction [3]. There is also a and, where possible, offers a preventive or management strat- relation between position based on the Winter classi- egy. Complications, such as pain, dry socket, swelling, fication and the appearance of postoperative complications. paresthesia of the lingual or inferior alveolar nerve, bleed- Mesioangular and distoangular impaction are associated ing, and infection are most common. Factors thought to in- with nearly twice as many complications as the other tooth fluence the incidence of complications after third molar re- positions [3]. Other authors state that horizontal and moval include age, gender, medical history, oral contracep- distoangular impactions are inclined to develop more com- tives, presence of , poor , smoking, plications [4]. Deep impacted third molar surgery needs a type of impaction, relationship of third molar to the inferior bigger flap design. Tissues in the neighborhood and mus- alveolar nerve, surgical time, surgical technique, surgeon cles can receive more damage because of this wide and large experience, use of perioperative , use of topical access flap [5]. antiseptics, use of intra-socket medications, and anaesthetic There is a distinctive association between age and technique. observed postoperative complications. These associations For the general dental practitioner, as well as the oral result from the fact that the intervention in older patients and maxillofacial surgeon, it is important to be familiar with lasts longer because of increased density. Age depended all the possible complications after this procedure. This im- maturing of tooth root formation and decreased healing ca- proves patient education and leads to prevention, early rec- pacity lead to intensive postoperative complications. Bruce ognition and management. and Chiapasco et al. state that older patients have more pain, and as postoperative complications [5]. Key words: third molar surgery, complication, man- It seems that female patients show higher accident and dible, complication rates [1]. Monaco et al. reported that the inci- dence of postoperative edema in female patients (12.7%) is INTRODUCTION significantly higher than in male patients (1.4%) [5]. Surgical removal of impacted third molars is one of The experience of surgeon also appears to be a deter- the most common procedures carried out in oral and maxil- mining factor in the development of postoperative compli- lofacial surgery. Most third molar surgeries are performed cations and can result in a longer treatment process, social without complications. However, such procedure can lead and financial difficulties and a corresponding decrease in to serious complications to the patient, such as hemorrhage, patient’s life quality [5]. persistent pain and swelling, infection, dry socket (alveolar Prior to any surgical procedure, the patient must be ), dentoalveolar fracture, paresthesia of the inferior informed about the possible accidents and/or complications alveolar nerve and of the lingual nerve, temporomandibular that may occur during the entire treatment, being aware of joint and even . The accident or the fact that any unexpected situation should be dealt with complication rates related to third molar extraction may vary the best possible way [1]. between 2.6 and 30.9 %, being the results influenced by dif- It is thought that complications like pain, edema and ferent factors, such as age and health condition of the pa- trismus are caused by surgical trauma depending on the in- tient, gender, tooth impact level, surgeon’s experience, smok- flammatory process. In surgeries for impacted mandibular ing, intake of contraceptive medicine, quality of oral hy- third molar, time of the intervention is thought to be associ- giene, and surgical technique among others [1]. The overall ated with tooth position, angle and the experience of the incidence of complication and the severity of these compli- surgeon and these parameters determine the difficulty of the cations are associated most directly with the depth of im- surgery and are related to the intensity and time of pain, paction and with the age of the patient [2]. There appears to edema and trismus. Longer surgical interventions are be a direct relation between the degree of impaction of the thought to increase tissue damage and vascular permeabil- extracted tooth and the incidence of postoperative compli- ity can cause postoperative edema and affect its intensity.

1202 http://www.journal-imab-bg.org / J of IMAB. 2016, vol. 22, issue 3/ In addition, it was reported that longer surgical interventions 7 days [7]. lead to increased surgical trauma [5]. In comparing edema with gender, age, position of the While evaluating the postoperative complications tooth, classification of the tooth, retention, angle, systemic regarding the width and depth of impaction, pain and conditions, bad habits, use of oral contraceptives and men- swelling was common in IIIA (37.5%) followed by IIIB struation, statistically significant differences were observed (20%); dry socket was common in IIIA, IA and IIA which between edema and classification of the tooth. More edema was 12.5%, 5% and 4.8% respectively; trismus occurred was observed in class II than in classes I and III. There was a more in Class IIIB (20%), Class IIIA (12.5%) and Class IB statistically significant difference between edema and par- (6.8%) and paresthesia was least common and occurred in tial bony and complete bony impaction [5]. 2 patients (0.7%) [4]. The application of ice packs to the face may make the patient feel more comfortable but has no effect on the magnitude of edema [2]. Hemorrhage might happen during (accident) or after Most of the surgeons prescribe corticosteroids to con- (complication) the surgery, being classified as late or recur- trol surgical outcomes and yield a comfortable post-surgi- rent hemorrhage. In situations of intense bleeding classified cal healing period [6]. as late, the hemorrhage happens only once, after the end of In the initial phase of the inflammatory process, the procedure. In recurrent hemorrhages, more than one in- corticosteroids acts by suppressing the production of vasoac- tense bleeding situation takes place, even after initially ex- tive substances such as prostaglandins and leukotrienes. This tinguished. reduces fluid transudation and edema. These drugs help to Anatomical variations, tooth proximity to the vascu- control mild pain hence they should be used in conjuga- lar nerve bundle of the mandibular canal, and coagulopathy tion with potent . Prolonged use can delay heal- are the main causes of hemorrhage [1]. Patients who have ing and increase patient’s susceptibility to infections. But known acquired or congenital coagulopathies require exten- in the doses are for shorter duration, hence sive preparation and preoperative planning (eg, determina- chances of adverse effects are very rare. [6] tion of International Normalized Ratio, factor replacement, The dose of the drug should be more than the corti- hematology consultation) before third molar surgery [2]. sol released normally by the body. Due to this reason, some Bleeding can be minimized by using a good surgical authors consider that 8 mg dexamethasone and 40 mg meth- technique and by avoiding the tearing of flaps or excessive ylprednisolone were used which corresponded to 200 mg of trauma to bone and the overlying soft tissue. When a vessel cortisol. [6] is cut, the bleeding should be stopped to prevent secondary Dexamethasone significantly reduced the incidence hemorrhage following surgery [2]. of swelling as compared to methylprednisolone. This is at- The most effective way to achieve hemostasis follow- tributed to the half-life of the drug which is more than meth- ing surgery is to apply a moist gauze pack directly over the ylprednisolone. The efficacy of dexamethasone is also due site of the surgery with adequate pressure for some minutes to the reason that it reduces the formation of thromboxane or use of bone wax, absorbable hemostats or electrocoagu- A2 which in turn reduces the amount of prostaglandin E2 lation. that is formed [6]. Good results were also obtained with 32 In some patients, immediate postoperative mg methylprednisolone and 400 mg ibuprofen administered hemostasis is difficult. In such situations a variety of tech- 12 h before and 12 h after surgery respectively. niques can be employed to help secure local hemostasis, Postoperative edema can also be controlled with dex- including over suturing and the application of topical amethasone administered in the submucosa [8]. Submucosal thrombin on a small piece of absorbable gelatin sponge into administration of 4 mg dexamethasone 1 h before surgery the extraction socket [2]. has been compared with that of 8 mg dexamethasone plus 2 Some authors affirm that the hemorrhage cases repre- g amoxicillin/clavulanic acid two times a day. Both dosages sent from 0.2 to 5.8% of the accidents/complications and improved swelling versus untreated groups, but no differ- that the compression technique is safe and reliable in the ences were observed between the two dosage regimens. control of intense bleeding [1]. In striking contrast with this observation, some au- In comparing hemorrhage with gender, age, position thors reported that in patients undergoing surgery for im- of the tooth, classification of the tooth, retention, angle, sys- pacted third molars, administration of 8 mg dexamethasone temic conditions, bad habits, use of oral contraceptives and 1 h before surgery, followed by 750 mg paracetamol every menstruation, there weren’t any statistically significant dif- 6 h for 4 days produced a better control of swelling com- ferences [5]. pared to treatment with 4 mg dexamethasone [9]. Dexam- ethasone has also been administered 1 h before surgery (4 Edema/ postoperative swelling mg orally) and 12 h after surgery (4 mg IV), along with Postsurgical edema is an expected complication af- antalgic agents (30 mg ketorolac IV), when pain was present. ter third molar surgery. It can be caused by the response of [10] In this study, treatment with dexamethasone always pro- the tissues to manipulation and trauma caused during sur- duced a good control of swelling, as measured 24 and 48 h gery. Its onset is gradual and maximum swelling is present after surgery. during 48 h after surgery [6]. Regress of the swelling is ex- Elhag et al. [11] reported that administration of 10 pected by the 4th day and completely resolution occurs in mg dexamethasone IM, 1 hour before surgery and 10–18 h

/ J of IMAB. 2016, vol. 22, issue 3/ http://www.journal-imab-bg.org 1203 later together with therapy (400 mg oral metroni- no significant differences were reported, pharmacological dazole, administered pre- and post-surgically), significantly treatment reduced swelling and was better tolerated by pa- reduces swelling when compared to only postoperative treat- tients. It is then reasonable to conclude that most authors ment, without corticosteroids. prefer secondary healing and/or draining rather than primary Although a significant reduction (50%) of swelling closure. was observed 2 days after surgery in patients treated with 4 Different surgical procedures have also been related mg dexamethasone IM, no effect was present after 7 days. to postoperative swelling. Osteotomy through piezosurgery However, when administered 5–10 min before surgery, 4 mg has given positive results on tumefaction compared to tra- dexamethasone i.v. was not effective in controlling edema ditional techniques. However, often, the studies analyzed did when no antibiotic therapy was associated with it. not involve extraction of impacted third molars, but general The investigated studies showed how the effective- osteotomy of the . [23, 24, 25] ness of the corticosteroid administration before surgery could Therapeutic effects of ice applied on a surgery wound not be considered as a predictable therapy in order to con- are due to changes of hematic flow and consequent vaso- trol the postoperative swelling and edema of the surgical area. constriction and reduced metabolism. In surgery and ortho- However, corticosteroids administration during the surger- pedics, in fact, the main function of ice on the treated area ies or in the postoperative period seems to give a great ben- is to produce and to control bleeding, re- efit for reducing the swelling and postoperative edema. sulting in reduced metabolism and control of bacterial Different surgical strategies have been reported in the growth. [26] The application of ice does not have to be too literature to reduce the postoperative discomfort after the long as this may be responsible for tissue death due to pro- third molar surgeries. They can be used either separately or longed vasoconstriction, and capillary thrombosis in association with pre- or postoperative strategies. Differ- and lymph stasis. ent kinds of flaps have been used during extraction of im- It is interesting to note that low laser dosage (4 J cm2), pacted third molars, specifically to assess whether a marginal applied soon after surgery, produces a good control of swell- flap could control postoperative swelling better than a ing, especially in patients treated with 4 mg dexamethasone paramarginal one [12]. No significant difference in the en- IM [27] tity of swelling was observed after using the two kinds of The first physiological response of tissues to cryo- flaps. However, there were no significant differences between therapy is reduction of local temperature that causes reduced the marginal and paramarginal flaps in terms of swelling. cellular metabolism. In this way, cells consume less oxygen In contrast, Kirk et al. [13] reported significant dif- and resist longer to ischemia. [28] In the treatment of im- ferences, particularly for swelling and pain, during the 2nd pacted third molars, the use of ice shows a good efficacy in day post-surgery between a group with a buccal flap and a reducing post-surgery swelling and pain. In the postopera- group with a triangular flap modified by Szmyd [14]. In the tive period, the use of ice pack is largely recognized to pro- latter case, an increased swelling was observed. Pasqualini vide good results and it helps the patient to cooperate with et al. [15] have compared 100 patients treated with tight su- pharmacological treatments and/or intraoperative strategies ture with 100 patients sutured after removal of 5–6 mm of in the prevention of edema. All pharmacological therapies mucosa distally to second molar to allow draining. Using used post-surgery are valid although they differ in the com- this procedure, postoperative swelling was reduced especially pounds used and their ways of administration. [29] on days 2 and 4, while in the group treated with tight su- ture, the peak of swelling was observed on day 3. Trismus According to several authors, [16, 17, 18] tight clo- Trismus is a normal and expected outcome following sure favors edema formation by creating a unidirectional third molar surgery. valve that allows fragments of food to reach the cavity, but Trismus is evaluated by the distance between the up- not to leave it easily. This can be the origin of local infec- per and lower right central at the maximum tion, , edema and potential and opening; a modification of this method calculates the quo- pain for difficult draining. [19] tient between preoperative and postoperative distance. Other According to other authors different factors such as authors simply consider two possible alternatives: presence edema, pain and trismus that follow extraction of impacted or absence of trismus, taking into account a difference of third molars can be related to suture technique and to sur- 5mm. There is a reliable and valid patients’ self assessment gery length, and the use of a draining tube can be helpful in of mouth opening using a cardboard scale [9] reducing or preventing postoperative swelling. [20]. This has Like edema, stiffness usually reaches its peak on been confirmed in a study specifically designed to compare the second day and resolves by the end of the first week. [2] postoperative responses in two groups, one treated with su- There is a strong correlation between postoperative ture and the other with draining. In the latter, a clear reduc- pain and trismus, indicating that pain may be one of the prin- tion in edema formation was observed. Rakprasitkul and cipal reasons for the limitation of opening after the removal Pairuchvej [21] obtained similar results. They reported re- of impacted third molars. [2] duced swelling with suture in the presence of a draining tube In comparing trismus with gender, age, position of the when compared to the primary suture. tooth, classification of the tooth, retention, angle, systemic In a different study, the effect of draining has been conditions, bad habits, use of oral contraceptives and men- compared with methylprednisone treatment. [22] Although struation period, statistically significant differences were

1204 http://www.journal-imab-bg.org / J of IMAB. 2016, vol. 22, issue 3/ observed between trismus and partial bony impaction of prophylaxis for healthy people undergoing extraction of tooth. The absence of trismus after the extraction of partial third molars. [30] bony impacted tooth was 49.6%, presence of edema was The antibiotic prophylaxis is the most controversial 62.5%, while these means were 0% and 37.2% for trismus factor among the others, and some studies highlight that its after the extraction of mucosal impacted teeth and 13.3% use is necessary only when there is exposure of the vascular and 37.5% for trismus after the extraction of complete bony nerve bundle of the mandibular canal, increasing the chances impacted teeth. [5] of infection in up to seven times. [1] Patients who are administered steroids for the control Antibiotic therapy to treat established infection or as of edema also tend to have less trismus.[2] Dexamethasone prophylactic strategy to prevent distance site infection or caused less trismus compared to methylprednisolon. [6] to control postoperative discomfort in third molar surgery is today a broadly accepted indication with documented ef- Pain ficacy. [8]. Another postsurgical morbidity expected after third According to the literature review, the use of the an- molar surgery is pain. The post surgical pain begins when tibiotics before surgery could be considered a predictable the effects of the local subsides and reaches peak procedure to avoid and control the possible infection related levels in 6 to 12 hours postoperatively. 37.7% patients re- to the surgery. If infection and inflammation are present in ported mild pain on the third post-operative day and 43.4% the surgical area, an antibiotic therapy seems to give a bet- patients had no pain on the seventh post operative day. [7] ter clinical compliance of the tissues undergoing surgery. A large variety of analgesics are available for man- The antibiotic administration before, during and after sur- agement of post surgical pain. The most common ones are gery seems to be a better therapeutic choice for controlling combinations of analgetics (Metamizol), Paracetamol and the infection arising in the postoperative period [29] nonsteroidal anti inflammatory analgesics. Analgesics should Factors such as the patient’s age, osteotomy tech- be given before the effect of the local anesthesia subsides. niques and/or tooth section, delay in repairing the socket, In this manner, the pain is usually easier to control, requires previous local inflammation, surgeons with little experience, less drug, and may require a less potent . The ad- and lack of antibiotic prophylaxis are considered to pre- ministration of nonsteroidal analgesics before surgery may dispose the infection. [1] be beneficial in aiding in the control of postoperative pain. [2] Alveolar Osteitis (AO) [dry socket] Women may be more sensitive to postoperative pain The sequence of normal healing after extraction does than men; thus, they require more analgesics. [2] not always occur. In some instances, early clot formation in Swelling, pain and trismus are considered as transient the socket is followed by premature clot or loss, ac- complications and are expected with surgery. Although tran- companied by pain and a fetor oris. [31] sitory, these conditions can be a source of anxiety for the The alveolar osteitis (dry socket, alveolitis sicca patient.[7] dolorosa, localized alveolar osteitis, fibrinolytic alveololitis is a disturbance in healing that occurs after the formation of Infection a mature blood clot but before the blood clot is replaced An uncommon post surgical complication related to with granulation tissue. [31] The primary etiology appears the removal of impacted third molars is infection. to be one of excess fibrinolysis, with bacteria playing an im- The postoperative infection rate reported in the lit- portant but yet ill-defined role. This fibrinolysis occurs dur- erature varies between 1.5% and 5.8%,or between 0.9% and ing the third and fourth days and results in symptoms of pain 4.3% depending on the articles consulted. [3] and malodor after the third day or so following extraction. Infection after removal of mandibular third molars is The source of the fibrinolytic agents may be tissue, saliva, not so common complication. About 50% of infections are or bacteria. [2] localized subperiosteal abscess-type infections, which occur The reported incidence of alveolitis varies widely, 2 to 4 weeks after a previously uneventful postoperative from as low as 0.5% to as high as 68.4%, but most studies course. These are usually attributed to debris that is left un- indicate a rate between 5% and 10%. Diagnostic criteria, der the mucoperiosteal flap and are easily treated by surgi- which vary from author to author, might partly explain this cal and drainage. Of the remaining 50%, few variation. [3] The alveolar osteitis or dry socket is charac- postoperative infections are significant enough to warrant terized by an intense and throbbing pain that cannot be con- surgery, antibiotics, and hospitalization. [2] trolled by common pain killers, starting between the second Antibiotic prophylaxis reduces the risk of experienc- and fifth days after the surgery, with unpleasant smell and ing infection, alveolar osteitis and pain after third-molar ex- without incorrupt tissue in the interior of the socket. [1] tractions in healthy adults, but it also results in an increased Some researchers classified alveolitis as being alveo- risk of mild, transient adverse effects. Given the low risk of lar tissue necrosis with exposed bone, with a prolongation infection after tooth extraction in healthy young adults, sub- of pain between 5 and 7 days, of a neuralgic character, in- stantial increased risk of experiencing adverse effects, the tense or severe. Other authors offer a more descriptive defi- potential development of resistant bacteria due to antibiotic nition: the presence of a gray necrotic clot relative to a bare use and the management of infection if it occurs, some au- area of the socket, along with great stench and pain in the thors did not support routine prescription of antibiotic zone. A further diagnostic criteria was pain and discomfort,

/ J of IMAB. 2016, vol. 22, issue 3/ http://www.journal-imab-bg.org 1205 if medication does not alleviate the pain, and if exposed Nerve Disturbances bone or necrotic debris is showing in the alveolus. [32] Neurological damage of the lingual or inferior alveo- As possible risk factors, we can include untimely sur- lar nerve (IAN) is one of the least desired complications of gical maneuvers, surgery difficulty level, surgeon’s experi- third molar surgery. The incidence of IAN and lingual nerve ence, tooth position in the arch, smoking, patient’s age, be- reported, ranges from 0.4% to 22% and most of these ing a female, use of oral contraceptive and corticoids, use injuries undergo spontaneous recovery. [4, 7 ] of local anesthetics with vasoconstrictor, and intrinsic fac- Neurosensory deficit after lower third molar surgery tors such as coagulopathy among others.[1] occurs at prevalences of 0.1% to 22% for lingual nerve (LN) The incidence of postoperative alveolitis in associa- deficit and 0.26% to 8.4% for inferior alveolar nerve (IAN) tion with oral contraceptive (OC) use has been investigated deficit. Sensory deficits may present as anesthesia, by many authors, with conflicting results. Some studies have hypoesthesia, hyperesthesia, or dysesthesia in the distribu- demonstrated an increased rate of alveolitis among women tions of the LN or IAN, with or without taste disturbance, if taking OC but others did not. This discrepancy can be ex- the LN is also affected. Within 4 - 8 weeks after surgery, 96% plained by the lower concentration in the new gen- of inferior alveolar nerve (IAN) injuries recover [33], and the erations of OC. [3] recovery rates are not influenced by gender and only slightly Cohen et al. suggest, on a literature review of the most by age [34]. Some injuries may be permanent, lasting longer relevant articles, that there are not enough data to consider than 6 months, and with varying outcomes ranging from mild oral contraceptive as an important risk factor to dry socket hypoesthesia to complete anaesthesia and neuropathic re- in elective surgeries to extract third molars. Not enough evi- sponses resulting in chronic pain. The results showed that dence was found to affirm that the menstrual cycle influences after 6 months, recovery seemed to be slight, and confirmed the development of dry socket. On the other hand some au- that permanent IAN dysfunction is more frequent after M3 thors affirm that women who use oral contraceptive medi- removal in patients older than 30 years. cine have five times more chances of developing dry socket One third of neurosensory deficits after third molar than men. [1] Other considerations that must be pointed out surgery can be permanent. Although some patients can cope regarding dry socket is the patient’s age, which might hinder well with mild to moderate hypoesthesia of the affected area, the repairing process and healing of older patients and those who are severely affected often request treatment for worsen the bone tissue quality. [1] The incidence of dry the condition. The quality of life of patients with anesthesia, socket seems to be higher in patients who smoke. [2] severe hypoesthesia, hyperesthesia, dysesthesia, or taste dis- The occurrence of dry socket can be reduced by sev- turbance of the affected area can be significantly impaired. eral techniques, most of which are aimed at reducing the bac- Different treatments have been reported in the literature, yet terial contamination of the surgical site. Presurgical irriga- their efficacies seemed to be variable. [35] tion with antimicrobial agents such as reduces The lingual nerve is most often injured during soft the incidence of dry socket by up to 50%. Copious irriga- tissue flap reflection, whereas the inferior alveolar nerve is tion of the surgical site with large volumes of saline is also injured when the roots of the teeth are manipulated and el- effective in reducing dry socket. Topical placement of small evated from the socket. [2] amounts of antibiotics such as tetracycline or lincomycin There are various neurosensory tests used to evaluate may also decrease the incidence of alveolar osteitis. [2] Main- objectively the severity of nerve injury and monitor recov- tenance of the coagulum inside the socket by using appro- ery of the sensation. [35] priate suture techniques may also help in the prevention of Risk factors as regards to damage to IAN are the depth this complication. [1] To the subject of clot stabilization and of impaction and dental proximity to alveolar canal.[4] Ac- healing, one should consider the use of resorbable substances cordingly, Blondeau and Daniel [3] recommended that pro- such as gelatin sponge, polylactic acid, and methylcellulose phylactic M3 extraction should be avoided in patients aged as clotstabilizing socket implants. The record of such sub- 24 years or older because of a high possibility of complica- stances in preventing AO is mixed,but the combinations of tions such as permanent neurosensory deficits, infection, and these inexpensive materials with topical socket medicaments alveolar osteitis. may yield a decreased tendency for clot lysis and greater The risk factors associated with permanent neurosen- mechanical strength to the bulk blood clot. [31] sory deficit are Pell and Gregory IC or IIC classification of The goal of treatment of dry socket is to relieve the impaction, age greater than 24 years, and in females. [3] patient’s pain during the delayed healing process. This is When an injury to the lingual or inferior alveolar usually accomplished by irrigation of the involved socket, nerve is diagnosed in the postoperative period, the surgeon gentle mechanical débridement, and placement of an ob- should begin long-term planning for its management includ- tundent dressing, which usually contains . The dress- ing consideration of referral to a neurologist and/or ing may need to be changed on a daily basis for several days microneurosurgeon. [2] and then less frequently after that. The pain syndrome usu- The available treatment modalities for an LN and IAN ally resolves within 3 to 5 days, although it may take as long injury after third molar surgery seem to have unpredictable as 10 to 14 days in some patients. There is some evidence clinical outcomes and rarely produce complete recovery. that topical antibiotics such as may hasten What is more, there is insufficient information to indicate resolution of the dry socket.[2] the best timing for the treatment of nerve injury after third molar surgery. It has been shown that a significant portion

1206 http://www.journal-imab-bg.org / J of IMAB. 2016, vol. 22, issue 3/ of the neurosensory deficit of an LN or IAN after third mo- Another study demonstrated that when compared with lar surgery can recover spontaneously. Therefore, LN or IAN untreated controls, subjects undergoing third molar surgery injuries tend to be treated in a delayed fashion, depending have a statistically insignificant increased incidence of TMDs on the recovery pattern and the extent of disturbance on a 6 months post-operatively. [40] patient’s social life. It was suggested Wallerian degeneration Treatment of TMD may involve anterior splints oc- and a smaller Schwann cell population adjacent to the site clusal splints, splints with posterior occlusal support, occlu- of nerve injury can significantly affect the long-term out- sal adjustment, removable therapeutic partial prostheses, al- come of delayed nerve repair. [35] though therapeutic support regimens in the areas of psychol- Surgery (external neurolysis, direct suturing, autog- ogy, NAID(local and per oral), and physical enous vein graft bridging nerve defect, gore-tex therapy(exercises) and phisioterapy may be associated de- tubing,bridging nerve defect) remained the mainstream of pending on the needs of each patient. [37] treatment of a neurosensory deficit after third molar surgery. Most subjects who underwent surgical treatment had LN in- Rare complications include oro-antral fistulas (0.008– juries. This can be explained by the fact that the tongue is a 0.25%), maxillary tuberosity fractures (0.6%) and mandibu- very sensitive organ and any taste disturbance with an LN lar fractures (0.0049%) [41] injury might contribute to a higher demand for nerve repair after an LN injury. Several reports suggested a higher chance Maxillary tuberosity fracture and oro-antral commu- of spontaneous reinnervation and recovery of the nerve nication within the inferior alveolar canal. Full recovery of sensation Upper third molar lies just in front and within the max- after surgical treatment of the IAN or LN injury is uncom- illary tuberosity. [42] mon. Fewer than 30% of patients were reported to have Maxillary tuberosity fracture is one of the major com- achieved “complete recovery” after external neurolysis of plications of maxillary third molar extraction. [42] the injured nerve. [35] The incidence of tuberosity fracture during upper Nonsurgical alternatives for treatment of neurosensory molar extraction is relatively low. [43] Bertram and al. re- deficit are vit. B complex, laser therapy (LLLT), ported this incidence to be around 0.6%. [44] corticosteroids, electrophoresis with nivalin, acupuncture. It Large fractures of the maxillary tuberosity should be was believed LLLT could decrease scar formation and in- viewed as a grave complication.[42] crease collagen formation and healing, which are favorable The fracture of a large portion of bone in the maxil- features in nerve regeneration. [35] Scarring at a site of nerve lary tuberosity area can result in torrential, life-threatening repair is thought to impede the regeneration of damaged hemorrhage due to close proximity of significant vessels to nerve fibers. Our recent studies have shown that anti-scar- the area. [42, 44] ring agents (such as antibodies to TGFâ1 and 2) can be used Fracture and loss of the maxillary tuberosity not only to reduce this problem, and hopefully will result in enhanced risks exposure and tearing of the lining but regeneration. [36] also changes the shape of the alveolus such that subsequent prosthodontic management may be difficult. [45] Temporomandibular disorders (TMDs) There is a reported case of subconjunctival Temporomandibular disorders (TMDs) is the term hemorrhage after tuberosity fracture. [42] used to refer to dysfunctions characterized by pain in the Cattlin reported that, after maxillary tuberosity frac- region of the temporomandibular joints and periauricular ture, deafness occurred from the disruption of the pterygoid area, limitations and deviations in the mandibular move- hamulus and the tensor veli palatine, in turn collapsing the ments, joint noises and an altered occlusal relation opening of the eustachian tube. The patient also suffered per- (Dworkin et al, 1990). [37] manent restricted mandibular movements because of the dis- The etiology of TMD is multifactorial. When all risk ruption of the pterygoid muscles and ligaments. [43] factors for TMDs are considered individually, the two most The etiological factors listed in the literature that are prevalent factors identified on this population were tooth responsible for a fractured maxillary tuberosity during up- clenching (77% of the patients) and self-reported stress per molar extraction include the following: large maxillary (59.3%) followed by antecedents of extraction of wisdom sinus with thin walls/sinus extension into the maxillary tu- teeth (34.3%), endotracheal intubation (30.7%), biting hab- berosity and/or large projection lengths of root apices in its (29.3%), gum chewing (28%), and previous orthodontic the sinus cavity; unerupted maxillary third molar; fusion treatment (28%) [38] between the maxillary third and second molar; teeth with Third molar removal has been implicated as a precipi- large divergent roots; teeth with an abnormal number of tating event for disorders. [39, 37] roots; teeth with prominent or curved roots; teeth with den- That is the reason why Deangelis highlights the importance tal anomalies, such as and over-eruption;tooth of including an assessment of the temporomandibular appa- ankylosis; of upper molar teeth; chronic ratus in the pre-operative evaluation of patients with im- periapical infection; excessive force during the tooth luxa- pacted third molars. [39] tion accomplished by the and others. [43] The traumatic removal of the mandibular third molar Upon discovering that a maxillary tuberosity has frac- may promote post surgical consequences such as orofacial tured, the dentist must first halt the procedure before inad- pain and limited mandibular movements. [37] vertent laceration of the adjoining soft tissue occurs and then

/ J of IMAB. 2016, vol. 22, issue 3/ http://www.journal-imab-bg.org 1207 determine the extent of the fracture by palpating the mobile cled buccal fat pad grafting could corrected the defect with- fragment. After performing the dissection of the soft tissues, out generating any sequelae and/or great postoperative dis- immediate removal of the small fractures, including the tooth comfort to the patient.[47] with small bony fragments, may be the best option, because of the difficulty incurred when attempting to retain the Mandibular fractures bone.When a large bony fragment is present, it is recom- Mandibular fractures are a rare but severe complica- mended (i) that the extraction be abandoned and surgical tion of third molar removal. [49] removal of the tooth be performed using root sectioning, (ii) Reports of mandibular fracture during and after third that the dentist tries to detach the fractured tuberosity from molar removal are uncommon. [50] the roots, or (iii) that the dentist stabilizes the mobile part(s) The incidence is reported to range from 0.0046% to of the bone by means of a rigid fixation technique for 4–6 0.0075%. It may occure, either operatively, as an immedi- weeks and, at a future moment, attempts a surgical removal ate complication during surgery or postoperatively as a late without the use of a forceps. [43] complication, usually within the first 4 weeks post surgery. Oroantral communication is the consequence of a [51] loss of continuity between the maxillary sinus and the oral Its occurrence is likely to be multifactorial includ- cavity. Sinus floor perforation occurs due to the close ana- ing: age, gender, angulation, laterality, extent and degree tomical relationship between this structure and the distal of impaction, relative volume of the tooth in the jaw, pre- teeth. [46] existing infection and associated pathologies (bone lesions) Oroantral communications (OAC) are common surgi- contributing to the risk of fracture. [49, 51] Other impor- cal complications of dental procedures. An oroantral fistula tant factors are the anatomy of the teeth and the features is a pathological condition in which the oral and antral cavi- of the teeth roots. [52] ties have a permanent communication by means of a fibrous Weakening of the as a result of decrease in conjunctive tissue fistula coated by epithelium. [47] its bone elasticity during aging may be the cause of the Intraoperative fracture of the root, higher degree of higher incidence of fractures reported among patients over impaction and higher age of the patient are associated with 40 years of age at the time of surgery. [51] De Silva reported a greater likelihood of oroantral perforation. [48] that fractures predominantly occur in patients who are older A study of 465 extractions and 592 osteotomies of than 25 years. [52] the upper third molars revealed that 13% were related di- Men may be more likely to have late fractures [53]. rectly to the diagnosis of a perforated maxillary sinus. Acute The effect of gender may be related to biting force. Males oroantral communication occurred as a result of the removal usually show higher levels of biting force as compared to of completely impacted teeth in 24%, by removal of par- females. [51] tially impacted teeth in 10% and in fully erupted third mo- Patients having full dentition are able to produce peak lars in 5% of all cases. These differences are significant. In levels of biting forces, that are transmitted to the weak man- 83%, the diameter of the oroantral perforation was less than dible during mastication and consequently the risk of frac- 3 mm. In 19% of all sinus openings, a buccal sliding flap ture is high, regardless of gender. [51] was used to close the extraction wound.[48] The literature indicates that the risk of pathological OACs 2 mm in diameter or smaller are likely to close (late) fracture of the mandibular angle after third molar sur- spontaneously, without the need for surgical intervention. gery for total inclusions (class II-III, type C) is twice that of [47] If the exposure of lining is at the apex of a deep socket partial inclusions due to the necessity of ostectomies more with stable bone walls, and the coagulum is not displaced generous than those for partial inclusions. [52] or breaks down, then it may not be necessary to make ar- The true incidence of postoperative mandibular frac- rangements for complete soft tissue closure but to simply tures as a result of the extraction is difficult to establish, inform the patient, give advice on post-operative care and as there are reports on postoperative traumatic mandibular review as necessary. [45] fractures that could have happened with an intact mandi- It has been recognised for many years that some small ble, and the occurrence of the two conditions may be just oroantral communications will heal without the formation a coincidence. [51] of a fistula or chronic sinusitis. However, this will depend Postoperative fractures were more common than upon many factors including the health of the patient and intraoperative fractures (2.7:1) and occurred most frequently their oral soft tissues, the presence or absence of preexisting in the second and third weeks (57%). [49] Other studies show infection, the dimensions of the tooth socket and the post- that 67.8% of fracture cases happened in the second and third operative care provided by the patient. [45] week post surgery. [52] A ‘cracking’ noise was the most fre- OACs 3 mm in diameter or larger, or OACs associated quent presentation (77%). [49] Such cracking noise reported with maxillary or periodontal inflammation, may persist , and by the patient should alert to a possible fracture, even if ini- surgical closure is recommended. Several techniques have tially the fracture is radiologically undetectable. [51] been used for OAC resolution, such as the use of mucope- Intraoperative fractures were more frequent among fe- riosteal flaps (vestibular, palatine, lingual or combined), bone males (M:F - 1:1.3) [49] grafts, or buccal fat pad grafts (Bichat ball). [47] Grafting of Pathological mandibular fractures were typically lo- the pedicled buccal fat pad is thought to be an efficient, safe cated anterior to the mandibular angle. [54] Wagner et al. and easy alternative to a larger oroantral fistula closure. Pedi- noticed a significant prevalence of fractures on the left side

1208 http://www.journal-imab-bg.org / J of IMAB. 2016, vol. 22, issue 3/ of the patient (70%) over the right side. This was explained early masticatory loads and prevent this complication. [52] by better visualization and control of the applied force by In selective cases, it is recommended that the patient follow the surgeon on the right side of the patient as compared to a soft diet for up to 4 weeks after the operation. [54] the left side.[51] The danger of an immediate jaw fracture can be avoided by means of proper instrumentation and by CONCLUSION refraining from excessive force on the bone. The tooth should Although clinical conditions associated with retained be sectioned in such a way as to minimize the extent of bone third molars are well understood, little is known about the removal and force caused by instrumentation. [50] It is more impact of those conditions on the quality of life among af- likely to occur with young or less experienced profession- fected patients. There is growing recognition that the im- als. [51] The postoperative or late fractures usually occur pact of oral conditions on quality of life is an important out- during the second or third postoperative week, and are prob- come that can be quite useful in making treatment decisions. ably as a result of high level of biting forces during masti- All the information in this review could be useful for the cation, when the patient was feeling better. [51] clinicians in order to show all the surgical and pharmacologic This is why it is extremely important to always pro- parameters that may influence the postoperative discomfort vide adequate instructions to the patient in order to avoid in the third molar surgeries.

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Please cite this article as: Deliverska EG, Petkova M. Complications after extraction of impacted third molars- literature review. J of IMAB. 2016 Jul-Sep;22(2):1202-1211. DOI: http://dx.doi.org/10.5272/jimab.2016223.1202

Received: 04/05/2016; Published online: 04/07/2016

Corresponding author: Elitsa Georgieva Deliverska – Assoc. prof., Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, Medical University- Sofia; 1, St. Georgi Sofiiski str., 1431 Sofia, Bulgaria E-mail: [email protected] / J of IMAB. 2016, vol. 22, issue 3/ http://www.journal-imab-bg.org 1211