Reconstruction of post release intraoral Oral Submucous Fibrosis defects by Extended Naso-Labial flaps versus Platysma myocutaneous muscle flaps: A Comparative Study.
We compared post operative outcome of extended Nasolabial flaps with Platysma myocutaneous muscle flaps, in the management of 20 randomly selected patients with histologically confirmed oral submucous fibrosis.
Patients and Methods: All patients in the study were treated by release of fibrous bands and bilateral coronoidectomy. In addition reconstruction was done in ten patients with extended nasolabial flaps (Nasolabial group) and in another ten patients with platysma myocutaneous muscle flaps (Platysma group). In the nasolabial group the mean preoperative interincisal mouth opening was 12 mm (range 3-14 mm) and in platysma group it was 11 mm (~ 3-13 mm). Vigorous post-operative physiotherapy was advised to all 20 patients and they were followed up for next 3 years .The interincisal mouth opening improved to 47 mm (~35-51 mm) in the nasolabial group and 48 mm (~ 41-52 mm) in the platysma group.
Conclusion: Both the procedures were equally effective in management of oral submucous fibrosis in terms of postoperative interincisal mouth opening. However the facial extra-oral scars were not aesthetically acceptable in the nasolabial group, which were prevented when Platysmal myocutaneous muscle flaps were used for the reconstruction of post release oral submucous fibrosis defects.
Oral submucous fibrosis is an insidious, chronic, disabling disease of obscure aetiology that affects the entire oral cavity, sometimes the pharynx and rarely the larynx. It is characterised by blanching and stiffness of oral mucosa, which causes progressive limitations of mouth opening and intolerance to hot and spicy food.
It is an established precancerous condition which is seen mostly in the Indian subcontinent. Its precancerous nature was first described by Paymaster 1, who recorded the onset of slowly growing squamous cell carcinomas in one third of the patients. Murti et al, 2 reported the malignant transformation of oral submucous fibrosis. As the aetiology is uncertain, its treatment has largely been symptomatic and various treatments have been described vastly in literature with inconsistent results.
In this study, two techniques for the closure of post release oral submucous fibrosis defects were compared. The importance of coronoidectomy was emphasised and two local flaps were used for reconstruction. We hypothecated that the platysma myocutaneous muscle flaps would be a better option than extended nasolabial flaps in terms of unaesthetic extraoral facial scars for the management of oral submucous fibrosis.3,4,5.
PATIENTS AND METHODS
Twenty consecutive patients who were treated at the Department of Oral and Maxillofacial surgery, SDKS Dental College and Hospital, Hingna, Nagpur (18 men and 2 women aged between 18 to 41 yrs of age), were randomly selected for this retrospective study. The study was approved by the institutional ethics committee. No patient had preoperative interincisal opening more than 25mm.
Following aseptic precautions, all patients were intubated using the fibreoptic bronchoscope and operated under general anaesthesia. Incisions were made using an electrosurgical knife from the corner of the mouth to the soft palate at the level of the linea alba avoiding injury to the Stenson’s duct. The bands were cut and the interincisal opening recorded. The coronoid processes were approached via the same incision and bilateral coronoidectomy or coronoidotomy was done. The maxillary and mandibular third molars were extracted.
In the nasolabial group, extended nasolabial flaps as described by Borle et al 4, were raised for grafting from the tip of nasolabial fold to the inferior border of the mandible. The flaps were raised bilaterally in the plane of the superficial musculo-aponeurotic system from both terminal points to the region of the central pedicle. The diameter of the pedicle was roughly 1cm and it was distanced 1cm lateral to the corner of the mouth (Fig. 1). The flap was transposed intraorally through a small trans-buccal tunnel near the commissure of the mouth without tension. The inferior wing of the flap was sutured to the anterior edge of the defect, while the superior wing was sutured to the posterior edge of the defect. The extraoral defect was closed primarily in layers after liberal undermining of the skin in the subcutaneous plane to prevent any tension across the suture line.
In the platysma group, a superiorly based platysma myocutaneous muscle flap was raised as described by D.A Baur 5 and used for reconstruction of the intraoral defects. With the neck hyper extended, the proposed skin paddle was outlined on the ipsilateral neck, below the inferior border of the mandible (Fig. 2). The superior incision was made first and the plane superficial to the platysma muscle was dissected carefully cephalic to the inferior border of the mandible. A skin incision was then made at the inferior line of the skin paddle, with additional exposure of the platysma muscle inferiorly. The platysma muscle was transected sharply at least 1cm inferior to the edge of skin paddle, and a subplatysmal plane of dissection developed just below the inferior border of the mandible. If the cervical branch of the facial nerve was to be incorporated, it was necessary to identify the nerve in the superficial layer of deep cervical fascia with careful dissection and preservation of its proximal portion. Once the plane of dissection was fully developed, the platysma myocutaneous flap was transected vertically, anteriorly and posteriorly for its full mobilisation. The flap was then introduced into the oral defect by creating an appropriately sized soft tissue tunnel. The harvested flap was sutured to the defect, which was created by release of the fibrous bands. The donor site was easily closed in layers, totally avoiding any unacceptable facial scar and obtaining by far a much better cosmetic result (as shown in Fig. 3b).
A soft temporomandibular joint trainer was placed in the oral cavity post operatively for 10 days to prevent dehiscence of the flap, as result of occlusal trauma. After a latent period of 10 days, physiotherapy was started with the help of Hister’s jaw exerciser to prevent contracture and relapse. The patients were instructed about the exercises and mandated to do them for the next 6 months until they were followed up in the Department of Oral and Maxillofacial Surgery.
We used the Student’s unpaired t test for statistical analysis of the study.
There were 2 groups of 10 patients each, one of which had nasolabial flaps, and the other platysma myocutaneous flaps.The differences in mouth opening were as shown in Table 1.
All patients in nasolabial group developed extra-oral facial scars, compared with none in the platysma group. The differences in mouth opening before and after the surgery were almost similar in both groups (p<0.01)
There were some complications in the nasolabial group including partial flap necrosis, particularly at the tips, temporary widening of oral commissure, unsightly extra oral scars as shown in (Fig. 3a), subluxation of the Temporomandibular Joint, perforation of the palate and intraoral growth of hair. In the platysma group, few patients developed temporary paraesthesia, which was noticed over the lateral cervical region, subluxation of the mandible and scars over the lower neck region which were usually covered by the shirt’s collar and not visible extra orally on the face. There were no delayed complications in the platysma group, but 2 patients in the nasolabial group had a “fish mouth” deformity, even after a year (Table 2).
The treatment of oral submucous fibrosis is mainly symptomatic, as the aetiology is not clearly understood and it is of progressive nature. Conservative treatments include multi-vitamins, iron supplementation and intra-lesional injections of hyaluronidase, placental extracts and steroids to name a few. Submucosal injections of various drugs may produce temporary symptomatic relief but can lead to aggravated fibrosis, pronounced trismus and increased morbidity from mechanical injury, secondary to the needle prick injury 6.
Different treatment plans and surgical interventions have been proposed by various authors with variable success rates. Excision of fibrous bands and propping the mouth open to allow secondary epithelisation is known to cause rebound fibrosis during healing. The release of fibrous bands followed by split thickness skin grafting results in high recurrence rate following contracture. The survival of full thickness skin grafts is questionable. The use of an island palatal flap based on the greater palatine artery was recommended by Khanna et al., but has limitations including involvement of donor tissue with the limited reach of the flap, as well as the need to extract the maxillary second molar tooth, so that the flap is not under tension.7
The bilateral tongue flap causes severe dysphagia, disarticulation, and it carries unwarranted risk of aspiration. It also provides a limited amount of donor tissue as its reach is inadequate. The doubtful stability of tongue flaps and their dehiscence are the most common post operative complications caused due to uncontrolled tongue movements.8 Buccal fat pads may also be used to cover the defects after excision of fibrous bands and also as their harvest is simple. However in patients with chronic disease they are likely to be atrophic. In addition, the anterior reach of buccal fat pads is inadequate and thus the region anterior to the cuspids often is required to be left raw; which therefore heals by secondary intention and subsequent fibrosis, leading to gradual relapse. 9
Bilateral radial forearm flaps are hairy, and nearly half the patients require a secondary debulking procedure. Facilities for free tissue transfer are not universally available. 10 Caniff et al 11 recommended temporal myotomy or coronoidectomy to release severe trismus caused by the atrophic changes in the tendon of the temporalis muscle secondary to the disease. If the mouth opening was still less than 35 mm after bilateral fibrotomy, then for every case bilateral coronoidectomy was done, which increases the per-operative mouth opening.
Complications like extra oral facial scars and intraoral growth of hair were common observation in our study when extended nasolabial flaps were used for reconstruction of defects. The patient’s compliance was not very good as far as facial aesthetics were concerned in the nasolabial group. These issues are taken care of when the platysma myocutaneous flap is harvested. The technique of platysma muscle flap however is more challenging as compared to that of extended nasolabial flap and needs to be mastered properly.
Surgical management of oral sub mucous fibrosis not only permits mouth opening but also facilitates the oral examinations for early detection and timely management of malignant transformation. This comparative study of Nasolabial flaps versus Platysma myocutaneous muscle flaps for reconstruction of intraoral post release oral submucous fibrosis defects emphasises on avoiding the extra oral facial scars in the patient. The postoperative mouth opening three years after surgery was comparable in both the techniques, however with better aesthetic outcomes in the platysmal group.
We recommend the use of platysma muscle flap as compared to the extended nasolabial flap for reconstruction of the intraoral defects after release of oral sub mucous fibrosis .The facial aesthetics are not compromised in this technique. The risk of broadening of the commissure and pinched appearance of the lips are subsequently avoided. As the incision is far away from the face, and situated infero-laterally on the neck, the scars are hidden underneath the shirt’s collar, without hampering the facial aesthetics, avoiding an unsightly facial scar and ultimately resulting in better patient compliance and acceptance in today’s conscious society.