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The management of OSF over the past decades has been varied and largely unsuccessful, and the results if any, have been palliative. Elimination or even reduction of the habit of betel quid chewing has been advocated as an important preventive measure. At least in the early stages of OSF, it may slow the progression of the disease (Canniff et al. 1986, Rajendran 1994). The current treatment strategies, which have been used to improve the treatment regimes for OSF, are discussed below. Unfortunately none has been shown to be effective under controlled conditions.

1.7.1 Nutritional support

Supplementary diets for high protein and calories, vitamin B complex and other vitamins and minerals have been supported by many authors (Krishnapa 1965). These are commonly employed in combination with other putative therapeutic agents like ingestion of iodinated salt and/or local applications of steroids and placental extracts (Rajendran 1994). Martin and Koop (1942) considered vitamin- 812 deficiency to be important in the aetiology of degenerative changes in oral mucosa before malignant transformation. Sirsat and Khanolkar (1960) reported that the reaction caused by capsaicin in the connective tissue was enhanced by vitamin-Bi2 deficiency. Thus, administration of vitamin B complex was supported by both of them to relieve glossitis, inflammation of the tongue, cheilosis, burning sensation and mouth opening in OSF patients (Maher et al. 1997).

1.7.2 Immunomodulatory drugs

Local and systemic application of glucocorticoids and placental extracts are commonly used in India. The users in India speculate that the cytokines released by the sensitised T lymphocytes following the antigenic effect of placental extracts and glucocorticoids act as immunosuppressive agents (Gupta and Sharma 1988). These are also thought to prevent or suppress inflammatory reactions, thereby preventing fibrosis by decreasing fibroblast proliferation and collagen deposition (Rajendran 1994).

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1.7.3 Physiotherapy

Physiotherapeutic measures such as forceful mouth opening and heat therapy have been tried. The former has been almost discarded owing to the poor results and the fact that it may accentuate the fibrosis. Heat has been commonly used and the results have been described as satisfactory (Gupta and Sharma 1988). It can be in the form of hot rinses, lukewarm water, or selective deep heating therapies like short wave and microwave diathermy. The latter avoids the inadvertent heating of the superficial tissues like skin and adipose tissue. Microwave diathermy is said to be superior to short wave, because selective heating of the juxta-epithelial connective tissue is possible, thereby limiting the area treated (Gupta et al. 1980a, Kakar 1985).

1.7.4 Local drugs

Kakar (1985) investigated the effects of local infiltration of hyalase in the treatment of OSF with or without dexamethasone and placentral extracts. In the study he divided the patients in four different groups using i) hyaluronidase alone ii) in combination with corticosteroids iii) with placental extract and iv) a control group with corticosteroid only. The treatment regimen was continued for ten weeks. The results of this study showed that the steroids brought about a distinct decrease in the burning sensation and the incidence of painful ulceration. The other three groups did not show any improvement after the treatment. The author failed to show any histological change in the connective tissue and in the improvement of mouth opening even after the treatment with corticosteroids, which indicates that the treatment regimens are ineffective or just palliative.

!n vitro, collagen from patients with OSF, in contrast to normal collagen, showed to be attacked rapidly by hyaluronidase (Chen and Lin 1986). Gupta and Sharma (1988) mentioned that hyaluronidase lowers the viscosity of the intercellular cement substances by breaking down hyaluronic acid and also decreasing the collagen formation. They also mentioned that the effects of steroids and hyaluronidase are thought to be responsible for the satisfactory results obtained in OSF patients who have severe limitation in mouth opening. They further recommended that chymotrypsin, an endopeptidase, hydrolyses the ester and peptide bonds, thus acting as a proteolytic and anti-inflammatory agent.

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1.7.5 Combined therapy

As mentioned above significantly better results have been claimed by giving local injections of chymotrypsin, hyaluronidase and dexamethasone together than with one drug alone or a combination of dexamethasone with either chymotrypsin or hyaluronidase (Gupta and Sharma 1988). Sharma et al. (1987) observed that the OSF symptoms included local ischaemic effects secondary to local fibrous conditions, hyperkeratosis, and loss of suppleness. Therefore, they supported combined therapy with nylidrin hydrochloride (a peripheral vasodilator), vitamins D, E and B complex, iodine, placental extract, local and systemic corticosteroids, and physiotherapy and claimed a success rate of 62% in a clinical trial. However, another study by Borle and Borle (1991) in a group of 326 OSF patients with two different treatment regimens, one with conventional submucosal injections of steroids and hyaluronidase, and the other with topical application of vitamin A, steroid and oral ingestion of iron, reported that neither of the treatments were significantly better to improve the mouth condition, and was purely palliative.

1.7.6 Surgical management

Krishnapa (1965) attempted to bring relief to patients by using mouth-gags to open the mouth while the patient was anaesthetised. They achieved only a little improvement, which was not substantial enough to give the patient any great relief from the debilitating fibrosis. Rajendran (1994) suggested for the extraction of teeth, if needed before commencement of any treatment in the management of OSF, might be helpful to relief undue affects on the already inflamed and atrophied mucosa. Removal of partially erupted third molars and all other inflamed teeth may result in considerable improvement in mouth opening in OSF patients (Canniff et al. 1986). Surgical measures such as forcing the mouth open and cutting the fibrotic bands under anaesthesia have resulted in more fibrosis and disability (Harris and Hopper unpublished observations). Submucosal resection of fibrotic bands and replacement with a partial-thickness skin or mucosal graft have also been attempted; modification of this surgical procedure by carrying out a bilateral temporalis myotomy seems more promising but unreliable. A new treatment regimen composed of surgical excision of the fibrotic bands with submucosal placement of fresh human

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placental grafts, followed by local injections of dexamethasone was recommended for advanced cases. The rationale for using placental grafts in OSF is that they have both a hormonal and a mechanical effect; the biogenic stimulant effect is because the placenta is a homograft, i.e. immunologically competent and rich in steroids, proteins, chorionic gonadotrophins, oestrogen and progesterone. The grafts are easily mouldable and undergo total absorption after prolonged periods, thus mechanically preventing fibrosis (Gupta and Sharma 1988).

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