Lesion one or leukoplakia: Oral leukoplakia is a white patch that cannot be rubbed off and cannot be characterized clinically or histopathologically as any other condition, and is not associated with any physical or chemical agent except tobacco. Usually, term leukoplakia implies only the clinical feature of a persistent adherent white patch.

A typical white patch of leukoplakia develops slowly, over weeks to months. The lesion may eventually become rough in texture, and sensitive to touch, heat, spicy foods and other irritation.

In our study, lesion one, i.e. leukoplakia variables, is not significant in groups of control and cases (p = 0.005). Lesion one (leukoplakia) absent in groups I, II and IV, while only 2% lesion one present in group III. Males are more prone for the development of leukoplakia than females. This is probably males having more frequency and duration of tobacco chewing than females.

Erythroplakia is a clinical term used to describe a fery red patch that cannot be clinically or pathologically distinguished a reasonable other definable disease.³ The clinical appearance of erythroplakia is described as red macule or patch with a soft, velvety texture most often occurring on foor of mouth, lateral tongue, retromolar pad and soft palate.⁴

Our results indicate that tobacco chewing is a strong risk factor for erythroplakia. Dose response was also correlated with frequency of noxious habits with risk of erythroplakia.

Group III has been reported 0.3% prevalence of erythroplakia as a risk factor for both oral leukoplakia and oral cancer. Groups I, II and III did not report cases of erythroplakia.

Our results indicate that group III has a strong risk factor for development of erythroplakia as comparison groups I, II and IV.

Chewing tobacco may possibly be a strong risk factor for erythroplakia than smoking in the Indian population as is suggested for oral leukoplakia.⁵ Chewing tobacco may have a stronger effect than smoking because of direct contact of the tobacco carcinogens with the oral epithelium as chewing tobacco kept in the oral cavity.

Reverse smoking: None of the cases found as having tendency of reverse smoking in teenagers.

Lichen planus: It is a papulosquamous disease that characteristically involves mucous membrane, especially oral mucosa, genital mucosa as well as skin. The prevalence of lichen planus is unknown; however, it is thought to be less than 1% of the population.⁶

Our study finds prevalence of lichen planus to be only 0.4 and 2.6% present in groups III and IV of cases, among patient attending Dental OPD of IMS, BHU, Varanasi, and outside the OPD. In control group, i.e. groups I and II, no lesions of lichen planus were seen, which suggest that noxious oral habits have a definite relation with development of premalignant lichen planus.

It has also been seen that groups III and IV have lower socioeconomic status than groups I and II. Cases, i.e. socioeconomic status of group I V, are lower than groups III, II and I. Therefore, socioeconomic status of family also plays an important role in the development of the noxious habits.

In group I, only 2.4% parents were illiterate and 84.5% parents were have intermediate and above education within the group. In group II, 3.3% parents were illiterate and 89% parents were having intermediate and above education within the group. In group III, 40.4% parents were illiterate and only 20% parents were having intermediate and above education. In group I V, 61% parents were illiterate and 39% parents were having only primary education. Parental education also has affect over the development of noxious oral habits. It has been seen that higher parental education prevents development of noxious habits in their offspring.

Illiteracy or lower education status encourages development of noxious habits. In group I, only 1.2% patients were illiterate and 98.7% patients were having middle and above education. In group II, only 1.7% patients were illiterate and 98.3% patients were having education between middle and intermediate. In group III, 17.1% patients were illiterate and 28.6% were having primary education. 35.5% having middle and 18.4% high school, and only 0.4% having education of intermediate. In group IV, 53.3% were illiterate and 42.1% patients were having primary education. Only 4.6% patients were having middle and high school education. None of the patient were having intermediate or above education in group IV.

Recent studies reveal that age of lichen planus patient ranged from 10 to 65 years, and majority of patient falls in age group of 21 to 50 years. This finding supports the suggestion that younger patients tend to be affected in tropical countries.⁷ In our study, only teenagers were participated.

Lichen planus is said to affect female preferentially, however, in our study, 0.4% male case and 2.6% female case were affected. Male:female ratio is 0.153 recorded, has refects no significant difference in sex distribution (p = 0.004).

It is reported that childhood lichen planus is rare⁸ and familial lichen planus is not reported. One study reveals that incidence of childhood lichen planus is 2% of total lichen planus. Our study reveals that 2.6% female teenagers were affected. Study reveals that isolated oral lichen planus present in 15 to 35% of lichen planus patient.⁹¹⁰

Lichen planus tends to be intensely pruritic when purities present. It ranges from mild irritation to severe itching. In oral lichen planus, patient complains of burning and itching.

In our study, the incidence of lichen planus was 0.4% in male and 2.6% in female of cases (groups III and IV) which is comparable to the study of tag-El-Din Anbar et al [Dermatology. Online journal 2003;11(2):4] who find 0.28% incidence.

Oral submucous fibrosis: It is chronic, complex irreversible, highly potent, premalignant condition characterized by juxtaepithelial inflammatory reaction and progressive fibrosis of the submucosal tissues.

As the disease progresses, the jaw become rigid to the point that the sufferer feels ristricted mouth opening.⁶ Chronic exposure to the betel nut (gutkha, arecanut) or pan (betel quid chewing), chilli, pepper and prolong deficiency of iron and zink may lead to the alteration in oral mucosa which causes hypersensitivity to these irritants. This hypersensitivity reaction may often result in formation of collagen fibers in lamina propria. These collagen fibers are nondegradable and believed to be involved in the pathogenesis of submucous fibrosis.^11-13

In initial phase of the disease, the mucosa feels leathery with palpable vertical and circular fibrous band. In advanced stage, the buccal mucosa lost its resiliency and become blanched and stiff. It is postulated that disease developed initially in posterior part of oral cavity and gradually spread toward lips.

Since, pan masala and gutkha have higher concentration of areca nut and appeared to cause disease.

In our study, 2.4% males (group III) were affected and SMF did not find in females cases (group IV).

Mortality/morbidity: Submucous fibrosis (SMF) has high rate of morbidity because it causes a progressive inability to open the mouth, resulting difficulty in eating and consequent nutritional deficiency. SMF has significant mortality because it transform into oral cancer, specially squamous cell carcinoma at a rate of 7.6%.

Since, parental education, patient education and family economic status have a significantly affect in the development of noxious habits. These noxious habits have been responsible for the development of premalignant oral lesions.

This is the first time that a strong association between noxious oral habit and relative risk of leukoplakia, erythroplakia, palatal keratosis, lichen planus, submucous fibrosis and socioeconomic status was found in our case control study.