Assessing the gustatory threshold and salivary flow rate in very early oral submucous fibrosis

Oral submucous fibrosis (OSMF) was first described by Schwartz in 1952 in tobacco-chewing women of Indian origin in Kenya as atrophica idiopathica based on its clinical manifestations. It was later renamed as OSMF based on its histopathological nature. It is defined aptly by Pindborg and Sirsat as a chronic insidious disease affecting the oral cavity, and sometimes, pharynx predominant in the Indian subcontinent. [1-3] The disease is easy to diagnose but difficult to manage, and there are no reports suggesting its spontaneous regression. [4] Among the multifactorial etiology of the disease, betel quid chewing has been recognized as one of the most important risk factors. [5-9] Areca nut (AN) is commonly used worldwide as a psychoactive substance by approximately 600 million people. The arecoline and guvacoline alkaloids present in AN get hydrolyzed in the presence of lime (calcium oxide), into arecaidine and guvacine, respectively, which, in turn, induces progressive fibrotic changes culminating in OSMF. [10,11] In most cases, patients present with characteristic features including intolerance to spicy food and limited tongue and oral cavity movements. An additional feature noted in OSMF is reduced salivary flow rate (SFR) which, in turn, can have a significant impact on the oro-dental health. [12] Abstract Background: Early diagnosis of oral submucous fibrosis (OSMF) is difficult, given the insidious nature of its presentation. The earliest symptom in most cases is the burning sensation of the oral mucosa, especially to spicy food. If the burning sensation is accompanied by oral mucosal fibrosis and reduced salivary flow, it would strengthen the OSMF diagnosis, although at such a stage the disease would be considered well established and progressing. The ideal approach in treating OSMF would be to recognize and treat the disease before the mucosal fibrosis is established. The taste buds are highly sensitive to changes in their surrounding environment. Thus, we hypothesized that even at the incipient stages of OSMF, there could be taste alterations. Aim: The aim of the study was to assess potential taste alterations in patients diagnosed with very early OSMF with a history of areca nut (AN) habit. Materials and Methods: The study group (n = 70) consisted of patients clinicopathologically diagnosed with early OSMF with a history of AN use. The control groups (n = 30) were healthy individuals with no habit history. The patients were asked to sip and rinse four blinded solutions, each with sweet, sour, salty, and bitter flavors for 1 min each. Depending on the threshold of the taste perception, the comparison was made between the control and the OSMF patients. The flow rate was assessed by placing sterilized cotton in the patient’s mouth for 1 min. The saliva-soaked cotton was weighed, and the weight difference was taken as the salivary flow rate (SFR). Results: There was no significant difference (P > 0.05) in the SFRs between the control (0.55 ml/min) and the very early OSMF (0.41 ml/min) patients. The gustatory threshold of very early OSMF patients also remained similar to that of the control group (P > 0.05). Conclusion: In contrary to our hypothesis, there was no change in the gustatory threshold of the very early OSMF patients. Thus, gustation, similar to salivary flow, remains unaltered in the initial phase of OSMF and cannot be used as an early diagnostic indicator.