English

Abstract

BACKGROUND Mouth opening is an important clinical parameter in our daily clinical practice. Mouth opening and its adequacy is an important factor in the treatment and follow up of the common conditions involving head and neck. Normal mouth opening has been defined as the inter-incisal distance at the maximal mouth opening. The purpose of this study was to determine the normal range of maximal mouth opening in the young adult Kumaoni population between the age of 20-40 years. METHODS The study was undertaken in the institutional hospital, Almora. A total of randomly selected 200 subjects between the age group of 20-40 years representing a sample of dentate adults was included for the study. The sample was stratified into four groups according to age followed by gender stratification. The age groups were classified as 21-25 years (Group 1), 26-30 years (Group 2), 31-35 years (Group 3), and 36-40 years (Group 4). Each group comprised 50 patients (25 males and 25 females). All particulars of patients, relevant clinical history and examination findings were recorded in the clinical proforma after taking proper informed consent. The mouth opening was measured using a standardized protocol with a calibrated ruler, and the findings were recorded in millimetres. RESULTS The mean MMO for males was 51.85 mm [standard deviation (SD) ± 2.59]. The range was 48–56 mm. The mean MMO for females was 49.82 mm (SD ± 2.32). The range was 46–56 mm. In the age group of 21-25 years, the mean MMO was 50.14 (SD ± 2.53) mm. The mean value for males was 50.80 (SD ± 2.67) mm and for females was 49.48 (SD ± 2.25). In the age group of 26-30 years, the mean MMO was 50.20 (SD ± 2.54) mm. The mean for males was 51.16 (SD ± 2.52) mm and for females was 49.24 (SD ± 2.22). In the age group of 31-35 years, the mean MMO was 51.56 (SD ± 2.62) mm. The mean for males was 52.28 (SD ± 2.66) mm and for females was 50.60 (SD ± 2.44). In the age group of 36-40 years, the mean MMO was 50.83 (SD ± 2.66) mm. The mean for males was 53.56 (SD ± 2.62) mm and for females was 49.82 (SD ± 2.32). CONCLUSIONS The mean maximum mouth opening for male participants was 51.85 mm (SD 2.59) (Range: 48-56 mm). The mean maximal mouth opening for female participants was 49.82 mm (SD 2.32) (Range: 46–56 mm). The maximum mouth opening was observed to decrease with age. The mouth opening of females was also observed to be lesser than the males from the corresponding age groups. KEY WORDS Maximum Mouth Opening, MMO, Trismus, Oral Cavity, Jaw, TMJ, Kumaon