Determination of the biometric characteristics of palatine rugae patterns in Uttar Pradesh population: A cross-sectional study.

Background: Identification is the establishment of identity of an individual. The basis of dental identification is based on the observation that no two individuals can have same dentition. Palatal rugae are irregular, asymmetric ridges of the mucous membrane extending laterally from the incisive papilla and the anterior part of the palatal raphe. The location of palatal rugae inside the oral cavity confers them with stability even when exposed to high temperatures or trauma. Their resistance to trauma and their apparent unique appearance has suggested their use as a tool for forensic identification. Aims: To record the biometric characteristics of shape, size, direction, number and position of palatal rugae and analyze whether palatal rugoscopy can be used as a tool for personal identification and for sex determination. Settings and Design: A cross‑sectional study. Materials and Methods: The sample consisted of 100 subjects (50 males, 50 females) between 18 and 25 years. Maxillary impressions were made with elastomeric impression material and dental stone was used to make models. The palatal rugae patterns were traced and analyzed with a magnifying hand lens. The biometric characteristics of number, size, shape, and direction were analyzed using Thomaz and Kotz classification (1983). The casts were coded to blind the examiners about the identity of the subjects. Statistical Analysis Used: Unpaired t‑test and one‑way ANOVA using SPSS 19.0 statistical program for Windows. Results: The average number of rugae was slightly more in females. Wavy (44.9%) and curved (41.8%) shapes were more prevalent. Maximum number of rugae was found in E quadrant (40.73%). The average size was 9.221 mm. Most rugae were forwardly directed in both groups. Conclusion: This study concluded that rugae pattern are highly individualistic and can be used as a supplementary method for personal identification and sex determination. Further inter‑observer and intra‑observer variability were not found to be significant, which further validates the use of rugoscopy as a forensic tool.

A comparative study of p53 expression in hyperplastic, dysplastic epithelium and oral squamous cell carcinoma

Aim: To study oral hyperplastic epithelium, dysplastic epithelium and squamous cell carcinoma to determine (1) the prevalence of p53 protein immunoreactivity, (2) number of p53 positive cells, and (3) the area of localization of p53 protein immunoreactivity. Methods: Two contiguous sections from 30 tissue specimens (10 each from oral hyperplastic epithelium, dysplastic epithelium and squamous cell carcinoma) were subjected to hematoxylin and eosin (H/E) staining forhistopathological diagnosis and immunohistochemical (IHC) staining for demonstration of p53. p53 positivity was looked for in each IHC stained slide and the number of positive cells amongst 1,000 epithelial cells were recorded. The localization of these p53 positive cells within the strata (i.e.basal/suprabasal, spinous and superficial layers) of epithelium between 3 groups, and also with ineach group according to histological grades was recorded. Results: Higher p53 positive cell counts were demonstrated in oral squamous cell carcinoma compared to hyperplastic and dysplastic tissues. The expression of p53 in epithelial hyperkeratosis was mainly localized to basal epithelialcells whereas in epithelial dysplasia, it was predominantly localized to spinous epithelial cells. Conclusions: Qualitatively p53 is not a specific marker for malignancy of oral epithelium. However the quantitative analysis of p53 positive cells and their localization in oral epithelium is of importance as a marker for oral squamous cell carcinoma.