Coronoidectomy, masticatory myotomy and buccal fat pad graft in management of advanced oral submucous fibrosis

Abstract

The purpose of this study is to evaluate coronoidectomy, masticatory myotomy and buccal fat pad graft in advanced (Stage III–IV) oral sub mucous fibrosis (OSF). 10 patients with clinically and histologically confirmed advanced OSF underwent surgery entailing bilateral coronoidectomy, masticatory muscle myotomy and closure with a pedicled buccal fat pad graft followed by vigorous mouth opening exercises. The result was evaluated using the interincisal distance at maximum mouth opening as the objective outcome measure over a follow up period of 12 months. Results showed a mean interincisal opening of 14.7 mm preoperatively and 32.5 mm at 12 months postoperatively. Relapse was encountered in one patient who did not cooperate with the postoperative exercise regime. Results suggest this regime is effective.

Oral submucous fibrosis (OSF) is a chronic, progressive, precancerous condition of the oral mucosa, predominantly seen in the Indian subcontinent. Reports have shown that the prevalence of OSF in South East Asia ranges from 0.04% to 24.4%. Recent epidemiological data indicate that the number of cases has risen rapidly in India from an estimated 250,000 cases in 1980 to 2 million cases in 1993. In oral cancer patients, OSF is commonly coexistent with oral cancer lesions, which coupled with the comorbidity rate is more than 40%. The clinical picture is characterised by remission and relapses of vesicle formation, ulceration/stomatitis, blanching, pigmentation of the oral mucosa, alteration in salivation, intolerance to spices, burning sensation in the mouth, referred pain in the temporomandibular region, depapillation of the tongue, stiffness of the oral mucosa, progressive difficulty in opening the mouth and difficulty in phonation. Areca nut chewing has been identified as the most important risk factor.

Traditional Indian medicine (Ayurveda) uses the areca nut for the treatment of multiple ailments, including as an antihelminth, appetite stimulant, flatus reliever, dentifrice, diuretic and laxative. Reasons for using betel nut include inducing euphoria, combating fatigue, increasing salivation, satiation, and relief of toothache. It is addictive; its use is associated often with a sense of well-being. The oral health consequences of chewing betel nut are varied. Among its many effects on oral structures is the development of OSF, which is a premalignant condition.

OSF has been well established in Indian medical literature since the time of Sushruta. In the Susrutasamhita (Chapter 16 Mukharoga in Nidanasthana ) it is described as: ‘Swelling within the throat with burning, prickling pain, haemorrhage, putrid and necrosed muscle and caused by pitta is known as vidari occurring in mouth particularly in the side by which the patient lies.’

In modern literature OSF was first described by Schwartz in 1952. To aid treatment planning, Khanna and Andrade developed a classification system for OSF based on mean interincisal opening (MIO): stage I, early OSF without trismus (MIO >35 mm); stage II, mild to moderate disease (MIO 26–35 mm); stage III, moderate to severe disease (MIO 15–25 mm); stage Iva, severe disease (MIO <15 mm); and stage IVb, extremely severe–malignant/premalignant lesions noted intraorally.

Treatment of OSF is a challenge, especially as the disease progresses. Conservative treatment includes vitamins, iron supplements, intralesional injections of hyaluronidase, placental extracts and steroids. Submucosal injections of various drugs may produce temporary symptomatic relief, but can lead to aggravated fibrosis, pronounced trismus and increased morbidity, from the mechanical injury secondary to insertion of the needle and chemical irritation from the drug. Operations have been proposed by different authors with variable success rates. The various surgical procedures include excision of fibrous bands with or without grafts. Materials for attempted grafting included skin, placental grafts, tongue flaps, greater palatine pedicle flaps, buccal fat pad grafts, nasolabial flaps, radial forearm flap, temporalis fascia flap, artificial dermis and anterolateral thigh graft. Additional procedures, such as splitting the temporalis tendon, coronoidectomy and masseter muscle stripping have also been described to enhance mouth opening.

The present technique for release of OSF involves bilateral coronoidectomy, myotomy of masticatory muscles and oral mucosal band resection followed by raw wound coverage with a pedicled buccal fat pad graft.

Materials and methods

This study includes 10 patients who were referred to the Department of Oral and Maxillofacial Surgery with the chief complaint of long-standing difficulty in mouth opening and a positive history of betel nut, supari, tobacco chewing, with or without lime. All patients were examined thoroughly and clinically and those histopathologically confirmed as having stage III–IV OSF were included in this study. The patients were screened and their preoperative interincisal opening (IO) was measured and recorded. Before scheduling the patient for surgery, the effects of their habit on health and its effects postoperatively were explained to them. After thorough preoperative counselling about quitting their habit of eating gutka, pan masala or betel quid and agreeing to undertake postoperative physiotherapy, the patients underwent surgery.

All procedures were carried out under general anaesthesia; the patients were intubated using fibre-optic nasotracheal intubation.

The surgical procedure consists of 5 steps. Step 1 was resection of the fibrous bands ( Fig. 1 ). The fibrous bands were incised along the occlusal line starting from the angle of the mouth extending posteriorly up to the retromolar region, bilaterally, deep to the connective tissue. Step 2 was coronoidectomy and muscle myotomy ( Fig. 2 ). The procedure includes exposure of the coronoid process from the horizontal incision made for the resection of the fibrous bands. Insertion of the temporalis muscle is released from the coronoid process and the anterior border of the ramus of the mandible. An intraoral incision is made to release the mucosa, buccinator muscle, and pterygomandibular raphe. Step 3 was the removal of the third molar teeth. Step 4 was recording of intraoperative forced mouth opening of 35–50 mm ( Fig. 3 ), as measured from the incisor edges; this was considered to be the minimum acceptable opening in an adult. Step 5 was the release, mobilization and securing of the buccal fat pad graft ( Fig. 4 ). The buccal fat pad was approached by bluntly opening the fine haemostat and gently dissected until the fat protruded into the mouth. The buccal fat pad was teased into the mouth gently by applying external pressure over the cheek until a sufficient amount was obtained to cover the defect without tension. The buccal fat pad graft was secured in place with horizontal mattress sutures. The graft was secured with bismuth iodine paraffin paste soaked gauze along with a prefabricated splint using transcutaneous sutures with 1-0 mersilk.

Fig. 1
Resection of fibrous bands.

Fig. 2
Coronoidectomy and muscle myotomy.

Fig. 3
Forced intraoperative mouth opening.

Fig. 4
Release and suturing of buccal flap pedicle to the defect.

From the third postoperative day, patients began mouth opening exercises using wooden sticks, an acrylic cone, Heister jaw opener or Shekhars appliance, four times a day for half an hour. The frequency and duration were increased later until the values that were achieved intraoperatively were reached. All patients were prescribed a nutrient supplement such as vitamin A 50,000 IU in the form of chewable tablets once daily, vitamin B complex tablets 200 mg twice a daily, vitamin C 500 mg once daily, B-carotene tablets once daily with topical triamcinolone acetonide 0.1% applied to the mucosal surface at bedtime for a minimum of 6 months postoperatively.

Results

In all patients, the fibrosis mainly involved retro molar pad, buccal mucosa, and palatal mucosa; the soft palate was involved in 2 patients, and both upper and lower vestibule with labial mucosa in 3 patients. All the patients had varying amounts of restriction in tongue and soft palate function. 8 patients had a history of medical management of the condition for an average period of 14.3 months, but none had undergone any surgical procedure.

The preoperative MIO was 14.7 mm (range 2–20 mm). After release of fibrotic bands, coronoidectomy and masticatory muscle myotomy an intraoperative MIO of 46.4 mm was achieved ( Table 1 ). The total increment in IO during the operation was effectively 31.7 mm.

Table 1
Mean values and standard deviation for interincisal distance (mm).
Interincisal distance Mean value Standard deviation
Preoperative 14.7 4.5717
Intraoperative 46.4 4.8120
Postoperative 1 week 42.4 3.7771
Postoperative 1 month 38.2 5.6332
Postoperative 3 month 36.8 7.0206
Postoperative 12 months 33.1 11.7610

On the seventh postoperative day an MIO of 42.4 mm was observed. Regular mouth opening exercises commenced on the third postoperative day, four times a day for half an hour. An MIO of 38.2 mm was achieved after 1 month, 36.8 mm at 3 months follow up and 32.5 mm after 12 months ( Fig. 5 ). 1 month postoperatively, the buccal fat pad is completely epithelised with maximal IO of 35–45 mm ( Fig. 6 ).

Jan 26, 2018 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Coronoidectomy, masticatory myotomy and buccal fat pad graft in management of advanced oral submucous fibrosis
Premium Wordpress Themes by UFO Themes