Comparative Evaluation of Reconstructive Methods in Oral Submucous Fibrosis

Abstract

Background

Oral submucous fibrosis is a chronic, progressive, scarring, precancerous condition of oral mucosa which on progression causes severe trismus.

Aim and Objectives

To compare and evaluate the efficiency of buccal fat pad, platysmal mucocutaneous flap, nasolabial flap, collagen membrane graft, split thickness skin graft and temporoparietal fascia in reconstruction of surgical defect created by excision of fibrous bands in oral submucous fibrosis.

Results

After 6 months of follow-up, the interincisal mouth opening was 40.0 mm in case of buccal pad fat, 24.5 mm in temporoparietal fascia flap group, 33.8 in collagen membrane graft group, 34.5 mm in platysma flap group, 34.7 mm in nasolabial flap group, 29.3 mm in split thickness skin graft. ANOVA statistical analysis for postoperative interincisal distance at various time intervals and between pre-, intra- and postoperative interincisal distances were carried out which showed the results were significant at p value < 0.05 in all groups. No postoperative complications were noted in buccal fat pad group, split thickness skin graft group and collagen membrane group. However, platysmal group had flap necrosis and temporoparietal flap group patients had to undergo a second debulking procedure after one month.

Conclusion

From our study, we concluded buccal fat pad yields superior results with respect to postoperative mouth opening and related complications.

Introduction

Oral submucous fibrosis (OSMF), first described in the early 1950s, is a potentially malignant disease predominantly seen in people of Asian descent.

It is an insidious, chronic disease affecting any part of the oral cavity and sometimes the pharynx [1]. Occasionally preceded by and/or associated with vesicle formation [2], it is always associated with a juxta-epithelial inflammatory reaction, followed by progressive hyalinization of the lamina propria [3]. The later subepithelial and submucosal myofibrosis leads to stiffness of the oral mucosa and deeper tissues with progressive limitation in opening of the mouth and protrusion of the tongue, thus causing difficulty in eating, swallowing and phonation [4].

The disease is predominantly seen in countries like India, Bangladesh, Sri Lanka, Pakistan, Taiwan, Southern China, Polynesia and Micronesia. An update was conducted on previous published studies conducted in different parts India till 2017, by Bari et al. [4]. After observing the results of those studies, the authors stated that the prevalence of OSMF has increased over the last four decades from 0.03 to 6.42%. [4].

Treatment of OSMF is a challenge, especially as the disease progresses. Two main modalities of treatment were described depending on grading of OSMF by Khanna et al. [5]: Medical treatment and Surgical treatment.

In Grades I and II of Khanna’s classification system, medical line of treatment is the treatment of choice, whereas in Grades III and IV, surgery is the treatment of choice. Medical treatment includes vitamins, iron supplements, intralesional injections of hyaluronidase, placental extracts and steroids, followed by stoppage of habits and aggressive mouth opening exercises [6]. The surgical procedures include excision of fibrous bands with or without grafts or flaps [7]. Materials being used for grafting include skin, placental grafts and artificial dermis. Materials that can be used as flaps are tongue flaps, buccal fat pad, greater palatine pedicle flaps nasolabial flaps, anterolateral thigh flap, radial forearm flap, temporalis fascia flap [8].

Till date, no comparative study was found in the literature which gives a comprehensive view of various reconstructive methods used in OSMF.

Aim and Objectives

This study aimed to compare the usefulness and effectiveness of buccal fat pad graft, temporoparietal fascia flap, nasolabial flap, platysmal mucocutaneous flap, split thickness skin graft, collagen membrane graft in surgical reconstruction of buccal mucosal defects in oral sub mucous fibrosis, using inter-incisor distance as an objective criterion. The postoperative complications like donor site morbidity, healing of flaps, etc., were also evaluated.

Materials and Method

This retrospective study was carried out in the Department of Oral and Maxillofacial Surgery over a period of 10 years. A total of 60 patients suffering with OSMF were divided into 6 groups, with 10 patients each. Group 1—Buccal fat pad group (Fig. 1), Group 2—Temporoparietal fascia flap (Fig. 2), Group3—Collagen membrane graft group (Fig. 3), Group 4—Platysmal myocutaneous flap (Fig. 4), Group 5—Nasolabial flap group (Fig. 5) and Group 6—Split thickness skin graft group (Fig. 6). Patients suffering with bilateral OSMF lesions; Grade III and Grade IV oral submucous fibrosis were included in the study. Medically compromised patients, patients having OSMF on one side and those who had undergone previous treatment (medical/surgical) for OSMF were excluded from the study.

Fig. 1.

Reconstruction with buccal fat pad

Fig. 2.

Reconstruction with temporoparietal fascia flap

Fig. 3.

Reconstruction with collagen membrane graft

Fig. 4.

Reconstruction with platysmal myocutaneous flap

Fig. 5.

Reconstruction with nasolabial flap

Fig. 6.

Reconstruction with Split thickness skin graft

The preoperative interincisal distance was measured and recorded. The surgical procedure was carried out under general anaesthesia by the same team of surgeons, which included resection of fibrous bands, coronoidectomy, temporalis muscle myotomy, removal of all third molar teeth, and a forced intraoperative mouth opening of around 35–50 mm in all the patients [6]. Following these interventions, the flaps were harvested and sutured with the defect. Patients were advised to start mouth opening exercises using wooden sticks from 3rd postoperative day, with a frequency of four times a day with duration of half an hour, and later the frequency and duration was increased [21].

Mouth opening was recorded intraoperatively and at the intervals of 1st week, 1 month, 3 months and 6 months postoperatively. Also postoperative complications like scar, flap failure, donor site morbidity, flap hyperplasia, etc., were evaluated.

Statistical Analysis

The data collected were entered into Microsoft excel spreadsheet and then analysed using SPSS (version 20.0). ANOVA statistics was used at the level of statistical significance set at 0.05.

Results

The patients included in the study were in the age group of 16–40 years. The preoperative interincisal distance was in the range of 2–18 mm. After release of fibrotic bands, coronoidectomy and masticatory muscle myotomy, a mean forced intraoperative mouth opening of 48.1 mm was achieved in those patients covered with buccal fat pad [Group I], 47.2 mm was achieved in those patients covered with temporoparietal fascia flap [Group II], 47.8 mm in patients who were given collagen membrane graft [Group III], 45.8 mm in patients with platysma flap [Group IV], 45.0 in nasolabial flap [Group V] and 47.6 mm in split thickness skin graft group [Group VI]. After 1st week postoperatively, a mean mouth opening of 44.4 mm was observed in buccal pad fad group, 40.3 mm in temporoparietal flap group, 41.8 in collagen membrane graft group, 25.5 mm in platysma flap group, 38.4 mm in nasolabial flap group, and 43.3 mm in split thickness graft group.

Regular mouth opening exercises were commenced on the tenth postoperative day, with a frequency of four times a day and duration of fifteen minutes. Later, both the frequency and duration of exercise were increased, which aided in further increase in mouth opening. The interincisal mouth opening after 6 months of follow-up was 39.25 mm in case of buccal pad fat, 24.5 mm in temporoparietal fascia flap group, 33.8 mm in collagen membrane graft group, 34.5 mm in platysma flap group, 34.7 mm in nasolabial flap group, and 29.3 mm in split thickness skin graft group (Table 1). The patients were motivated both pre- and postoperatively for the cessation of habit and mouth opening exercises. Thus, the study concluded that buccal pad of fat yields superior results in reconstruction of buccal mucosal defects in surgical management of oral submucous fibrosis (Fig. 7).

Table 1.

Mean interincisal distance (in mm) before and after reconstruction with various flaps

Flaps	Preoperative interincisal distance	Intraoperative (forced) interincisal distance	Postoperative interincisal distance
			After 1st week	After 1 month	After 3 months	After 6 month	Mean	SD
Buccal pad fat	14.6	48.1	44.4	41.1	41.1	39.25	41.72	3.02
Temporoparietal fascia flap	10.5	47.2	39.89	36.8	29.6	24.5	32.7	7.31
Collagen membrane graft	13.4	47.8	41.8	38.6	37.7	33.8	38.37	4.1
Platysma flap	6.9	45.8	25.5	33.7	36.2	34.5	32.47	5.2
Nasolabial flap	11.8	49.5	38.4	36.3	34.4	34.7	35.95	3.58
Split thickness skin graft	11.8	47.7	43.3	37.4	33.3	29.3	35.83	6

Fig. 7.

Figure showing mouthopening at various intervals on reconstruction with buccal fat pad

ANOVA statistical analysis was done to find level of significance within each group between pre- and postinterincisal distances (Table 2). The level of significance was found to be highly significant (p < 0.00001) for each study group. This shows that each flap produced a significant change in the mouth opening postoperatively. The intergroup comparison was done using ANOVA statistical analysis to find the level of significance between all the study groups. Statistically it was observed that an insignificant difference (p-value > 0.05) was observed on comparing all the study groups. Post hoc Tukey test was used to analyse the statistical significance between each pair of groups and it was observed that level of significance was insignificant (p-value > 0.05), (Table 3).

Table 2.

Intragroup comparison for each flap between pre-, intra- and postoperative interincisal distance

ANOVA Statistical analysis	Buccal pad fat	Temporoparietal fascia flap	Collagen membrane graft	Platysma flap	Nasolabial flap	Split thickness skin graft
F-statistic	479.91311	416.60819	201.58567	275.35585	383.805	603.39008
df	18	18	18	18	18	18
p-value	< .00001	< .00001	< .00001	< .00001	< .00001	< .00001

Table 3.

Intergroup comparison between all the flaps

ANOVA statistical analysis	F-statistics	df	p-value*
	0.2023	47	0.9597
Post hoc Tukey test
Treatments pair	Tukey HSD Q statistic	Tukey HSD p-value*
BP VS TF	1.0634	> 0.05
BP VS CM	0.4207	> 0.05
BP VS PF	1.2588	> 0.05
BP VS NLF	0.6804	> 0.05
BP VS STF	0.6804	> 0.05
TF VS CM	0.6427	> 0.05
TF VS PF	0.1954	> 0.05
TF VS NLF	0.3830	> 0.05
TF VS STF	0.3830	> 0.05
CM VS PF	0.8381	> 0.05
CM VS NLF	0.2597	> 0.05
CM VS STF	0.2597	> 0.05
PF VS NLF	0.5783	> 0.05
PF VS STF	0.5783	> 0.05
NLF VS STF	0.0000	> 0.05

*p-value > 0.05 is insignificant

Failures in flaps were also observed in few cases (Fig. 8). In temporoparietal flap group, we observed presence of hyperplasia in patients. After one month, patients complained of bulkiness intraorally, which resulted in cheek biting during occlusion. The hyperplastic tissue was excised using electrocautery. After 7 days of excision of hyperplastic tissue, there was a complete healing and re-epithelisation, with no interference of tissues with occlusion. In one patient, there was failure of temporoparietal flap and his mouth opening got reduced to 10 mm.

Fig. 8.

Graft failure in all the study groups

In nasolabial flap group, one case had extraoral wound dehiscence. It got healed uneventfully in 1 week, after the excision of wound margin was done, inducing fresh bleeding and re-approximating the margins by sutures. In platysma group, after 1st week of time interval, 70% of the flaps on right side were viable, whereas 30% were non-viable. On left side, 90% of flaps were viable, whereas 10% were non-viable. Donor site morbidity, i.e. wound dehiscence was evident in 20% and in evident in 80% of cases. No postoperative complications were noted in buccal fat pad group, split thickness skin graft group and collagen membrane group.

Discussion

Oral submucous fibrosis was first described by Schwartz in the year 1952 as a chronic, progressive, scaring, disabling precancerous condition of oral mucosa. According to Aziz et al. [9], clinically the earliest sign of OSMF is mouth soreness with constant burning upon eating spicy foods.

Khanna et al. [5] in 1995 developed a group classification system for the surgical management of trismus: Group I Earliest stage without mouth opening limitations with an interincisal distance of greater than 35 mm. Group II Patients with an interincisal distance of 26-35 mm. Group III Moderately advanced cases with an interincisal distance of 15-26 mm. Fibrotic bands are visible at the soft palate, and pterygomandibular raphe and anterior pillars of fauces are present. Group IVA Trismus is severe, with an interincisal distance of less than 15 mm and extensive fibrosis of all the oral mucosa. Group IVB Disease is most advanced, with premalignant and malignant changes throughout the mucosa. In our study, we also used this classification to categorize the patients suffering with OSMF.

As OSMF progresses to moderate/severe trismus, surgical intervention is required. Multiple surgical modalities have been attempted, from moderately invasive to significantly invasive. In present study, resection of fibrous bands, coronoidectomy, temporalis muscle myotomy, removal of all third molar teeth. Similar treatment modalities are advocated by various authors in their studies [10, 11]. In various studies, use of different grafts has been advocated to cover the raw wound like split thickness skin grafts, full thickness skin grafts, island palatal flaps, buccal fat pad, bilateral radial forearm free flaps, temporalis pedicled flap, anterolateral thigh flap, collagen sheets, placental grafts, allografts [5, 8, 11–14]. Thus in our study we also used and compared the commonly used grafts for surgical intervention, i.e. buccal pad fat, temporoparietal fascia flap, collagen membrane graft, platysma flap, nasolabial flap and split thickness skin graft.

Maher et al. [15] suggested that interincisal distance may be used as an outcome measure of response to surgical intervention for treatment of OSMF. Thus in our study success of treatment outcome is observed by comparing the pre, inter and postoperative interincisal distances.

Our study revealed that buccal pad fat induced maximum interincisal opening postoperatively with no postoperative complications, thus proven to be the best graft out of the six study groups. Results obtained in our study were in accordance with other studies conducted by Mehrotra et al. [7] and Lai et al. [8]. This could be due to the fact that buccal pad fat has a good blood supply, efficient uptake at recipient site and spontaneous epithelialisation in oral cavity with minimal donor site morbidity, that make it an ideal flap. It also provides a sufficient bulk of the graft to cover the defect up to 3 × 5 cm [8], without compromising the blood supply. Highly vascular pedicled blood supply with easy aesthetic approach [7, 8] and no postdonor site morbidity make this graft valuable in reconstruction.

The order of success of graft determined on the basis of interincisal opening was buccal pad fat > collagen membrane > nasolabial > split thickness > temporoparietal > platysma graft, with no statistical difference among all the flaps.

In our study, collage membrane was proved to be a successful graft. The results of our study were similar to the study conducted by Paramhans et al. [16]. They advocated the use of collagen membrane; it is easily available, has simple procedure, good tolerance by oral tissues, no need to perform second procedure for obtaining graft or detachment of pedicle, no morbidities are associated with various other grafts and no problems associated with donor site healing [16].

The present study revealed that nasolabial and split thickness flaps produced similar interincisal openings and were found to be successful grafts without any evidence of complications and graft failure. Results of nasolabial graft were similar to study conducted by Gewirtz et al. [17]. They found that nasolabial flap is a dependable axial pattern flap with a mobile pedicle that can be safely transposed intraorally. Because of its longer and more versatile pedicle, the flap can be extended to the area of oral commissures [17]. Split thickness skin graft is a conventional technique that is still popular and reliable. In our study, split thickness flap produced good interincisal opening postoperatively, with no complications. Similar findings were observed in a study by Mehrotra et al. [7], who observed that esthetics and function achieved with split skin graft was good. In our study, we observed no postoperative complications. This is in contrast to the study by Khanna et al. [5] who reported the incidence of shrinkage, contraction, and rejection of split skin graft as very high, owing to poor oral condition, with recurrence in 12 cases. Mehrotra et al. [7] also observed some degree of relapse due to contracture of the graft.

The results obtained with temporoparietal flap in our study were quite acceptable, with one case showing postoperative complication. Similar to our study, Demirdover et al. also observed few complications like hematoma/seroma formation, wound healing problems, alopecia, partial or total flap failure with this flap. Although vascularity and flexibility of this flap offer the advantage of flap survival in hostile environment like oral cavity [19], the technique of this flap is very invasive, time-consuming and need great surgical skills [18, 19].

Our study revealed that platysma myocutaneous flap was the least successful flap in terms of outcome and postoperative complications. Similar findings were observed by Ramanujam et al. [20], who reported various complications like total or partial necrosis of skin island, fistula, dehiscence, hematoma and cellulitis, in around 18–45% of cases.

The present study revealed that use of various grafts gave promising results in increasing the postoperative mouth opening in patients suffering from OSMF. As the study was conducted on limited patients, thus more prospective studies should be conducted on more number of patients. More studies and clinical trials are required to study the use of various surgical techniques and different flaps in treating OSMF. Besides interincisal opening, various other parameters should also be studied to analyse the outcome of various grafts.

Conclusion

From the study, we concluded that based on interincisal opening, buccal fat pad yields superior results than other types of flaps. However, taking postoperative complications into consideration, platysma and temporoparietal flaps are least recommended flaps. We advocate the use of buccal fat pad as the best reconstruction option for the defects created by surgical treatment of oral submucous fibrosis.

Funding

None.

Compliance with Ethical Standards

Conflicts of interest

The authors declare that they have no conflict of interest.

Ethics Approval

As it is a retrospective study, ethics approval was not taken.