Duration Of Chewing Research Articles

Effect of tobacco chewing on semen parameters

Background: Tobacco is a plant with green foliage and tubular flowers. Biologically titled as Nicotiana tabacum. Tobacco is evil for human health. It has been noted that 35% of death worldwide happen due to the tobacco intake only. Individual with no education is 2.69 times more likely to smoke and chew tobacco than those with a postgraduate education. Tobacco causes reduction in sperm count, motility, and concentration. Objective: To affirm the deleterious effects of tobacco abuse on various semen parameters. Materials and Methods: This cross-sectional descriptive study was conducted on 100 healthy adults in GGH Hospital, Jamnagar, Gujarat, India. Out of which, 50 were tobacco chewers and 50 were nontobacco chewers. Semen was collected in the vicinity of laboratory bathroom and immediately handover to laboratory technician for evaluation of various parameters. Result: Result shows that there is a significant decrease in semen volume, sperm concentration, motility, and viability in tobacco chewers than control group. There was progressive decrease in sperm count and liquefaction time as the duration of tobacco chewing is increase. Conclusion: There is an adverse effect on all the seminal parameters who practicing of tobacco chewing as compared to non-chewers mainly sperm concentration, total sperm count, motility, and viability of sperm are also decreases in tobacco chewer than the control group. As the frequency of tobacco chewing is increasing, it is associated with more adverse effects on semen volume, count, concentration, motility, and viability of sperm.

The effect of mouth breathing on chewing efficiency.

To examine the effect of mouth breathing on chewing efficiency by evaluating masticatory variables. Ten adult nasal breathers with normal occlusion and no temporomandibular dysfunction were selected. Subjects were instructed to bite the chewing gum on the habitual side. While breathing through the mouth and nose, the glucide elution from the chewing gum, number of chewing strokes, duration of chewing, and electromyography (EMG) activity of the masseter muscle were evaluated as variables of masticatory efficiency. The durations required for the chewing of 30, 60, 90, 120, 180, and 250 strokes were significantly (P < .05) longer while breathing through the mouth. There was no significant difference in the glucide elution rate (%) for each chewing stroke between nose and mouth breathings. The glucide elution rates for 1- and 3-minute chewing were significantly (P < .05) lower while breathing through the mouth. However, there was no significant difference in the glucide elution rate for 5-minute chewing between nose and mouth breathings. While chewing for 1, 3, and 5 minutes, the chewing stroke and EMG activity of the masseter muscle were significantly (P < .05) lower during mouth breathing. It takes a longer amount of time to complete chewing to obtain higher masticatory efficiency when breathing through the mouth. Therefore, mouth breathing will decrease the masticatory efficiency if the duration of chewing is restricted in everyday life.

Betel quid oral lichenoid lesions: a hospital based cross-sectional study.

The aim of this study was to assess the prevalence and risk indicators of betel quid oral lichenoid lesions in chewers. A total of 1209 chewers were identified and categorized into three main groups based on the type of lesion: betel quid oral lichenoid lesions only, betel quid oral lichenoid lesions in association with quid-induced other oral mucosal lesions, and no lesions. Multinomial regression analyses were used to determine associations between dependent and independent variables. Betel quid oral lichenoid lesions were more common in individuals who chewed quid comprising both tobacco and areca nut, and in those who chewed it two to three, or greater than three, times a day. Betel quid oral lichenoid lesions+quid-induced other oral mucosal lesions were more likely to occur in females, and in individuals who chewed quid containing both tobacco and areca nut, in their processed and unprocessed forms, and greater than three times a day. The prevalence of betel quid oral lichenoid lesions was higher than that reported in previous studies conducted in India. Increase in the frequency and duration of quid chewing was associated with increased likelihood of developing these oral lichenoid lesions.

The Influence of a Soft Touch Therapy Flowtrition on Heart Rate, Surface Temperature, and Behavior in Horses

This study tested Flowtrition, a noninvasive soft touch therapy, on the mean and maximum heart rate (HRavg and HRmax, respectively), surface temperature in three body quadrants, and eight stress-related behaviors in horses. Fourteen gelded horses were randomly assigned to a control (CON, n = 5) group or a Flowtrition (treatment, TRT, n = 9) group. Each horse underwent four sessions with each session split into three 20-minute stages: Pre, During, and Post. At the end of the Pre stage in which neither group received any intervention, baseline heart rate, temperature, and behaviors were recorded. A During stage followed in which the TRT group received therapy, and the CON group was monitored and received no treatment. Within the Post period, both groups were monitored and response variables were recorded. The TRT group experienced a decrease (P < .05) of 10 ± 2.7 bpm in HRmax and 4.7 ± 0.8 bpm in HRavg between Pre and Post stages compared to the CON group, which experienced no shifts in heart rate. The group receiving therapy showed an increase (P < .05) in occurrence frequency and total duration of head lowering, licking and chewing, and yawning between Pre and Post stages; the CON group showed no behavioral shifts. The results show that Flowtrition induces a more relaxed state in horses as evidenced by a decrease in HR and increase in occurrence and duration of relaxation-related behaviors.

Oral Screening for Pre-cancerous Lesions Among Areca-nut Chewing Population from Rural India.

To detect early oral premalignant lesions (OPLs) in a rural population chewing tobacco-free areca nut preparations, determine their awareness level of oral cancer and educate them about maintaining good oral health. A total of 2175 18- to 65-year-old areca nut chewers (male:female ratio 2.5:1), without a history of consuming tobacco in any form, from the villages of two districts of the West Bengal state of India were screened clinically through oral examination for suspected OPLs. A pre-designed questionnaire was employed to record demographic data, information on tobacco-free areca-nut chewing habit and knowledge about oral diseases. Education on oral health was provided through distribution of printed leaflets, display of banner/posters and a public-announcement system. Chewing areca nut in the form of betel quid was more popular (90.7%) than chewing areca nut alone (9%) or tobacco-free packaged areca nut preparation sold as 'pan masala' (0.3%). OPLs were detected in 7.3% of the subjects, more among the males. An increasing incidence of OPLs could be observed with an increase in age as well as with duration and frequency of areca-nut chewing, while decreasing incidence was observed with an increase in educational level. Oral submucous fibrosis showed the highest prevalence (2.7%) among the various OPLs detected. Tobacco-free areca-nut chewing is an independent risk factor for the development of OPL and a large rural population still practices such high risk behaviour. In rural areas with limited health care resources, screening by visual oral examination involving minimum cost may prove useful to reduce oral cancer mortality.

Tobacco use, Body Mass Index, and Potentially Malignant Disorders Among petrol fillers in Pimpri-Pune (India): A descriptive study.

Background:Since petrol is combustible and smoking is banned at the petrol pumps, it may be predicted that use of smokeless tobacco is more prevalent among the petrol fillers. Also, smokeless tobacco is a major risk factor for developing oral potentially malignant disorders. The present study was conducted to determine the tobacco use, body mass index (BMI), and potentially malignant disorders among a cohort of petrol fillers and also to evaluate the interaction of tobacco use and BMI with the presence of potentially malignant disorders.Settings and Design:The study was conducted at 45 petrol stations located at Pimpri-Pune, India. A descriptive study design was used.Materials and Method:Four hundred and ten petrol fillers aged 17-64 years participated in the study. General information and tobacco history was obtained by interview. Height and weight were recorded to obtain BMI. Oral examination was conducted to identify the potentially malignant disorders.Statistical analysis:Chi-square test, Z test, and logistic regression were used. The level of significance was fixed at 5%.Results and Conclusions:It was found that 242 (59.02%) used tobacco in different forms. 77.68% were tobacco chewers, and 8.26% were smokers. Leukoplakia was prevalent among 68.47%, oral submucous fibrosis among 27.45%, and 5.08% had erythroplakia. Age (χ2 = 11.46, P < 0.05), duration (χ2 = 17.46, P < 0.05), and frequency of tobacco chewing (χ2 = 14.16, P < 0.05) were significantly associated with potentially malignant disorders. Tobacco chewing was more prevalent as compared to smoking. It can be concluded that the petrol fillers are at a high risk for developing oral potentially malignant disorders.

Does gum chewing increase the prevalence of temporomandibular disorders in individuals with gum chewing habits?

The effect of habitual gum chewing on temporomandibular joint function is controversial. This study evaluated the prevalence of temporomandibular disorder (TMD) in adolescents with and without gum chewing habits and the affiliation of TMD signs with gum chewing. This is a cross-sectional study. Subjects were studied in 2 groups. Subjects in the study group chewed gum for 30, 60, or 120 minutes in a 24-hour day. Subjects in the control group did not have a gum chewing habit. TMD signs of clicking, crepitus, and pain were documented for every subject. Age, gender, duration of gum chewing, and occlusal relationships were variable factors, and TMD signs (clicking, crepitus, and pain) were outcomes of the study. The chi-square test was used to compare TMD signs and gender in the 2 groups, and to evaluate the relationship between TMD signs and duration of gum chewing in the study group. An independent t test was applied to compare the ages of the 2 groups. Two hundred subjects participated in the study and were divided into 2 groups (100 subjects per group). An evaluation of the data showed no significant differences between the 2 groups in sex, age, and occlusion. The incidence of clicking and pain was statistically higher in the study group than in the control group (P < 0.05). Analysis of the data demonstrated considerable differences in clicking and pain among subjects with various gum chewing times in the study group (P < 0.05). The incidence of pain was higher in subjects with a class II skeletal pattern than others in the study group (P < 0.001). Nevertheless, no significant difference was noticed for clicking among subjects with various occlusions (P > 0.05). Considering that intensive gum chewing may affect TMD signs in individuals with a gum chewing habit. It seems a longer duration of gum chewing may increase the prevalence of TMD. Individuals with a class II skeletal pattern may be affected more than others.

Video-endoscopic comparison of swallowing waxy rice mochi and waxy wheat mochi: improvement of a traditional Japanese food that presents a choking hazard.

Mochi is highly cohesive and adhesive, and easy to choke on. Many of the fatal suffocation accidents with mochi occur in the elderly aged 65 years or older. These circumstances prompted us to investigate a special property of waxy wheat which is similar in texture to waxy rice, but is less cohesive and adhesive. We compared the differences in chewing and swallowing movements associated with eating waxy rice mochi and waxy wheat mochi between healthy adults and healthy elderly. Healthy elderly chewed mochi more and longer than healthy adults. Although there was no difference in the number of chewing cycles or total duration of chewing between the two types of mochi, waxy wheat mochi was easier to chew and left less pharyngeal residue. These findings lead us to suggest that waxy wheat mochi is promising as a food that is easy to swallow and difficult to choke on.

Evaluation of interleukin-1β and 8 in gutka chewers with periodontitis among a rural Indian population.

Smokeless tobacco-based oral-use products like gutka are popular in India. Gutka usage leads to increased periodontal destruction and inflammation; however, the relevant mechanism remains unknown. This study aimed to elucidate the role of gutka in periodontitis by examining its effect on the levels of interleukin (IL) 1β and IL-8 from the gingival crevicular fluid (GCF). A total of 45 patients were enrolled in this study. Thirty patients with periodontitis (15 gutka chewers [GCP] and 15 nongutka chewers [NGC]) and 15 periodontally healthy controls (HC) were selected. The full-mouth plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and recession (RC) were recorded. The IL-1β and IL-8 levels in the GCF of all subjects were assessed through an enzyme-linked immunosorbent assay (Quantikine). The IL-1β and IL-8 levels were not significantly higher in the GCP group (IL-1β, 369.01±273.44 µL; IL-8, 205.97±196.78 µL) as compared to those in the NGC group (IL-1β, 195.57±96.85 µL; IL-8, 178.61±149.35 µL). More gingival RC and loss of attachment was seen among the GCP group (RC: 2.02±0.31, P=0.013; CAL: 4.60±0.56, P<0.001) than among the NGC group (RC, 1.21±1.15; CAL, 3.70±0.32); however, PD was deeper among the NGC subjects (P=0.002). PI and GI were significantly higher for the periodontitis group (P<0.001) when compared to the HC, but there was no difference among gutka chewers and non-chewers (P=0.22 and P=0.89). A positive correlation was found between the IL-8 levels and the duration of gutka chewing (r=-0.64, P<0.01). Gutka chewing leads to increased gingival RC and clinical loss of attachment. There was no effect seen in the proinflammatory cytokine levels in the GCF of gutka users.

Clinical Evaluation of Gutkha chewing and Pattern of Bone Loss in Periodontitis

ABSTRACT Introduction Tobacco in the form of Gutkha is commonly used in India. The present study was done to analyze the extent and pattern of alveolar bone loss (ABL) among gutkha chewers who were having chronic periodontitis. Materials and methods A total of 55 habitual gutkha chewers within the age range of 18 to 35 years with chronic periodontitis, who were otherwise healthy were recruited for the study. Fourteen full mouth intraoral periapical (IOPA) radiographs were taken for each individual (a total of 770 radiographs) with the help of radiovisiography. Kodak dental software was used to analyze and measure the alveolar bone loss at each proximal site and data were computed as percentage alveolar bone loss. Results Almost all the subjects had poor oral hygiene status. Clinical parameters of periodontal examination represented by clinical attachment level, probing depth, gingival bleeding index had positive correlation with frequency and duration of gutkha chewing. The study population had a mean alveolar bone loss of 17%. Mean bone loss was more severe in mandible 18.3% ± 2.6, when compared with maxillary arch 15.7% ± 3.7. Conclusion Maximum bone loss was observed with molars and incisors. Alveolar bone loss was more frequently found in mandibular arch as compared to maxillary arch. How to cite this article Warad S, Chaudhari HL, Ashok N, Kalburgi V, Kalburgi NB, Jenifer HD. Clinical Evaluation of Gutkha chewing and Pattern of Bone Loss in Periodontitis. World J Dent 2014;5(4):199-203.

Correlation of Habits and Clinical Findings with Histopathological Diagnosis in Oral Submucosal Fibrosis Patients

Oral submucosal fibrosis (OSMF) is one of the most prevalent premalignant conditions in India which is easy to diagnose but difficult to manage. At present it is considered as irreversible and incurable. It has also been referred to as an epidemic in India. To correlate the frequency and duration of habits with clinical staging, functional staging and histopathological grading and to correlate the clinical and functional staging with histopathological grading. The study included a total of 90 subjects, 80 with OSMF in the experimental group and 10 patients in the control group. Patient personal history was recorded with chewing habits, including frequency and duration of chewing. The site of keeping the quid, time duration and whether he/she swallows it or spits it were also noted. Clinical staging was done on the presence of palpable fibrous bands. Functional staging was accomplished by measuring mouth opening. Incisional biopsy was done for all the patients for histopathological examination. Histopathological grading was according to Pindborg and Sirsat. The experimental group comprised 71 males and 9 females, the majority of which were in the age group of 21-30 years. Correlation of habits with clinical staging, functional staging and histopathological grading were significant (p<0.05). Clinical and functional staging did not correlate with histopathological grading, but the correlation of clinical and functional staging was highly significant (p<0.01). The widespread habit of chewing gutkha is a major risk factor for OSMF, especially in the younger age group. In this study, it was found that with increase in the duration and frequency of the habit the severity of the disease increased.

Effect of mouth breathing on masticatory muscle activity during chewing food

The aim of this study was to examine the effect of mouth breathing on masticatory muscle activity during chewing food. Masseter muscle activity during chewing of a rice ball was recorded in 45 adult volunteers (three women), identified as nose breathers. Surface electrodes were placed on the skin according to the orientation of the masseter muscle to record the activity of this muscle while the subjects chewed the food until swallowing. Each activity was recorded twice, once with nose breathing and once with mouth breathing induced by nasal obstruction. The integrated and mean electromyography values for mouth breathing were significantly lower than the values for nose breathing (P < 0·05). The resting and total duration of chewing were significantly prolonged (P < 0·05) and the active duration significantly shorter (P < 0·05) when breathing through the mouth compared with the nose. Significantly more chewing strokes were counted for mouth breathing compared with nose breathing (P < 0·05). Taken together, the results indicate that mouth breathing decreases chewing activity and reduces the vertical effect upon the posterior teeth.

The effect of chronic khat chewing on liver enzyme levels: a Yemenian study

Abstract Background Khat is a natural stimulant from the Catha edulis plant, which grows mainly in Yemen. The liver has been suspected to be vulnerable to the harmful effects of khat use. Aim The aim of the study was to investigate the effect of khat chewing on the liver function in healthy Yemeni individuals. Methods Liver function tests were performed on 30 chronic khat chewers (group I) and 20 individuals who did not chew khat (group II). Results Twenty percent of group I and only 5% of group II reported abnormally elevated alanine transaminase (ALT) levels, with no statistically significant difference between the mean ALT values (P = 0.208); 13.3% of group I showed elevated aspartate aminotransferase levels (P = 0.058). With regard to other liver function tests there was no statistically significant difference between the two groups. ALT levels increased with increasing duration of khat chewing. Conclusion Chronic khat chewing causes subclinical hepatocellular damage, whereas transient khat chewing has no effect on the liver function.

Gender difference in masticatory performance in dentate adults

PurposeTo clarify whether there might be a gender difference in masticatory performance in dentate adults. MethodsThirty male subjects and thirty female subjects were asked to chew gummy jelly on their habitual chewing side for 10, 15 and 20s and the amounts of glucose extraction were measured. The changes of both glucose extraction and standardized glucose extraction from 10 to 20s were investigated differently for males and females. The amount of glucose extraction was compared between males and females for each chewing duration. In addition, in order to confirm a gender difference in occlusal force, the maximum occlusal force was compared between males and females. ResultsFor both males and females, the amount of glucose extraction was lowest for 10-s chewing and increased significantly for 15-s and 20-s chewing. The mean standardized glucose extraction values increased in proportion with the duration of chewing. The standard deviations of the standardized glucose extraction were very small (below 0.02) for all chewing durations in both males and females. With regard to comparison of the glucose extraction between males and females, the amount of glucose extraction was significantly larger for males than for females for all chewing durations. The maximum occlusal force was significantly larger for males. ConclusionIt was suggested that it might be important to take into consideration gender-related differences while analyzing masticatory performance in dentate adults.

Prevalences of betel nut chewing and cigarette smoking among male prisoners before their imprisonment in Taiwan

Background/purposeSubstance abuse is considered prevalent in incarcerated populations; however, consumption of betel nut in this group has not been adequately studied. In the present study, we attempted to elucidate the prevalences of betel nut chewing and cigarette smoking, and determine the relationship between use of the two substances among prisoners before imprisonment in order to increase our understanding of this phenomenon. Materials and methodsIn 2000, a self-administered anonymous questionnaire was given to 976 male prisoners who were over 18 years of age and had been sentenced to imprisonment for a total incarnation period of more than 10 years in Kaohsiung Prison, Kaohsiung, Taiwan. ResultsThe response rate was 60.3% (589/976). Respective prevalences of betel nut chewing and smoking before imprisonment were 73.2% and 90.7%. Results of a cross-sectional analysis showed that dual-substance (betel nut and cigarette) users made up the majority (71.6%) of the study sample, whereas simple smokers and simple chewers comprised 19.0% and 1.5%, respectively. Only 7.8% of participants used neither substance. Smoking generally began 5.07 years before betel nut use. The duration of betel nut chewing was significantly associated with the daily quantity chewed (r=0.212; P<0.01), and a significant relationship was also found between the daily quantity chewed and smoking (r=0.314; P<0.01). Moreover, the daily quantity chewed increased concomitant with the chewing duration and daily quantity smoked. ConclusionsPrevalences of betel nut chewing and smoking are high among male Taiwanese prisoners before imprisonment. The association of use of these two substances among Taiwanese inmates was significant in a time-dependent manner.

Self-reports of eating quickly are related to a decreased number of chews until first swallow, total number of chews, and total duration of chewing in young people

ObjectiveThe validity of a self-questionnaire about eating quickly remains unclear. If a significant relationship between subjective and objective methods to evaluate eating quickly can be confirmed, then the subjective method can be widely and reliably used in many fields. This study investigated relationships between subjective and objective methods to evaluate eating quickly and also numerically characterized the kinesis of eating quickly in young people. DesignOne hundred and thirteen students (44 males and 69 females; mean age 22.8±2.0 years) were selected. All subjects completed written questionnaires, and number of chews until first swallow, total duration of chewing, number of chews, chewing rate and bite size were measured using test products (a Japanese cracker and rice ball). ResultsBoth male and female subjects who reported eating quickly showed a significantly lower number of chews until first swallow (Japanese cracker), a lower number of chews overall (rice ball), and a shorter total duration of chewing (rice ball) than other subjects. There was no difference in chewing rate between subjects who ate quickly or not. ConclusionsThese findings suggest that using test products, self-reports of eating quickly are related to a decreased number of chews until first swallow, total number of chews, and total duration of chewing, but not chewing rate, and that a self-reported questionnaire to evaluate eating rate is valid in young people.

Khat as a risk factor for hypertension: A systematic review.

Studies suggest possible newer risk factors for hypertension including Khat chewing, a plant which grows wild in countries bordering the Red Sea and along the east coast of Africa and the Arabian Peninsula. The objective was to synthesise the best available evidence on the epidemiological association between Khat chewing as exposure (potential risk factor) and hypertension. Subjects aged 16 years old or older regardless of gender and ethnicity, country of residence, Khat dose, frequency, duration of chewing or other characteristics of Khat exposure and co-presence of other known risk factors for hypertension.The focus of interest of this review was the epidemiological association between Khat chewing as exposure (potential risk factor) and hypertension as an outcome.Observational analytical studies (cohort studies, case-control studies and cross-sectional studies) were considered for inclusion. Three staged search strategy was used to identify all relevant published and grey literature in English language from 1988 to 2011. Databases searched were PubMed, CINAHL, PopLine, LILACS, MedNar and Embase. All papers selected for inclusion in the review were subjected to a rigorous, independent appraisal by the two reviewers prior to inclusion in the review using standardised critical appraisal instruments from the Joanna Briggs Institute. Due to poor internet service in our setting we were unable to use the Joanna Briggs Institute -software for data extraction and synthesis as approved in the protocol. Quantitative papers were pooled in statistical meta-analysis using the Review Manager Software. Odds ratios and their 95% confidence intervals were calculated for analysis. Two studies from Ethiopia and one from Saudi Arabia were identified. In the study done by Getahun et al. 44 of the chewers (n=324) and 34 of the non chewers (n=319) were found to have hypertension. Analysis of this study showed no statistically significant association between Khat chewing and hypertension (OR=1.29, 95% CI =0.80-2.08). In the second study done by Mossie, 29 of the chewers (n=277) and 73 of the non chewers (n=621) were found to have hypertension and there was no statistically significant association between Khat chewing and hypertension (OR=0.88, 95% CI =0.56-1.38). Seventy seven of the chewers (n=568) and 160 of the non chewers (n=1207) were found to have hypertension) in the third study done by Ibrahim, similarly there was no statistically significant association between Khat chewing and prevalence of hypertension (OR=1.03, 95% CI =0.77-1.37 in this study.On meta analysis, a total of 3321 subjects were involved. Of the Khat chewers (1174), 150 were found to have hypertension. On contrary, 267 of non chewers (2147) were found to have hypertension. Finding of the analysis showed no statistically significant association between Khat chewing and hypertension (Odds ratio=1.04, 95% Confidence Interval= 0.84, 1.29). The studies were homogenous, Heterogeneity test: Chi = 1.35, df = 2, (P = 0.51). The test for overall effect also showed no statistical significance at conventional levels (P>0.05). We did not find sufficient evidence to conclude that Khat as epidemiologic risk factor for hypertension.The present systematic review did not identify a statistically significant association of Khat chewing as epidemiologic risk factor for hypertension. This review identifies the need for further studies on Khat as an epidemiologic risk factor for hypertension considering further aspects of chewing, like dose-response, duration of chewing and co-existence of other co-morbid factors of hypertension.

Khat as risk factor for hypertension: A systematic review.

Review Questions/ Objectives The objective of this review is to systematically identify, appraise and synthesise the best available evidence on the epidemiological association between Khat chewing (different dose, frequency, and duration) as exposure (potential risk factor) and hypertension as outcome. The review question is: What is the best available evidence on the epidemiological association between Khat chewing and hypertension? Inclusion criteria Types of Participants Adults (18 years old or older) regardless of gender and ethnicity, country of residence, Khat dose, frequency, duration of chewing or other characteristics of Khat exposure and co-presence of other known risk factors for hypertension. Focus of the review The phenomenon of interest of this review is the epidemiological association between Khat chewing and hypertension change in blood pressure among individual who chew Khat.

Oral cavity cancer risk in relation to tobacco chewing and bidi smoking among men in Karunagappally, Kerala, India: Karunagappally cohort study

The Karunagapally cohort in Kerala, India was established in the 1990s. The present study examined oral cancer risk among 66,277 men aged 30-84 years in the cohort, using Poisson regression analysis of grouped data, stratified on attained age, calendar time, education, and family income. By the end of 2005, 160 oral cancer cases were identified by the Karunagapally Cancer Registry. Tobacco chewing increased oral cancer risk (P < 0.001). Particularly increased was the risk of cancers of the gum and mouth (relative risk [RR] = 4.7; 95% confidence interval [CI] = 2.8-7.9), which increased with higher daily frequencies (P < 0.001) and longer duration (P < 0.001) of tobacco chewing. Alcohol drinking was not significantly related to oral cancer risk regardless of tobacco chewing. Bidi smoking significantly increased oral cancer risk (RR = 2.6; 95%CI = 1.4-4.9) only among men without tobacco chewing habits. The risk increased with higher daily consumption (P < 0.001), longer duration (P = 0.001), and younger age at start of bidi smoking (P = 0.007). In location-specific analysis, bidi smoking was significantly associated with cancer of the gum and mouth (RR = 3.6; 95%CI = 1.1-12.1), and its risk significantly increased with larger daily consumption of bidis (P = 0.013) and younger age at the start of smoking (P = 0.044). Tongue cancer risk was significantly increased among men who smoked bidis for 30 years or longer, and men started bidi smoking at 18 years old or younger. The present study is the first cohort study showing that tobacco chewing increases cancers of the gum and mouth among men keeping chewing tobacco in the cheek, and that bidi smoking strongly increased oral cancer risk among men without a tobacco chewing habit.

Cytogenetic alterations in buccal mucosa cells of chewers of areca nut and tobacco

Objective The rationale of the study was to evaluate the cytological alterations especially micronucleus (MN) and other nuclear anomalies in buccal mucosa cells of chewers to understand the genotoxic and clastogenic potential of chewing mixture (containing areca nut and tobacco as main ingredients). Methods The buccal cytome assay involves the examination of epithelial smear to determine micronucleated cell and other nuclear anomalies after the Feulgen plus light green staining. The assay was applied to exfoliated buccal mucosa cells of 262 subjects [non-chewers – 161 and chewers – 101 (includes 20 subjects with OSMF)] and 1000 cells per individual were examined microscopically. Nuclear anomalies were compared among chewers, non-chewers and OSMF subjects and correlated with consumption of quids per day and duration of chewing in years. Results MN cells were found significantly ( p < 0.0001) higher among chewers and OSMF subjects as compared to non-chewers. Further analysis indicated that MN was significantly higher in OSMF subjects with respect to even chewers. Nuclear buds were significantly higher ( p < 0.0001) in OSMF subjects as compared to chewers as well as non-chewers. Nuclear anomalies viz. binucleated, karyorrhexis and karyolysis were also considerably higher in OSMF subjects as compared to non-chewers. Conclusion The MN and other nuclear anomalies reflected genetic damage and cytotoxicity, associated with tobacco and areca nut consumption. Further, these data reveal a risk for development of OSMF among chewers of mixture containing areca nut and/or tobacco, as all the OSMF subjects were chewers.