Reliability of palatal rugae patterns in individual identification

Background:

Dental identification plays a major role in mass disaster identification of human remains. Palatal rugae can be used as a substitute for a comparative method of identification.

Materials and Methods:

The present cross-sectional study was done with 137 pre- and post-orthodontically treated casts of patients, which were divided into 50 cases each of extraction and nonextraction and 37 cases of palatal expansion involving both extraction and nonextraction. Hydrocolloid (alginate) impression of the upper jaw of the patient was taken and then cast in the dental plaster of Paris material. Palatal rugae pattern was classified according to Lysellm, and Thomas and Kotze classification. Two Observers recorded the data, mean of two were taken for analysis.

Results:

On the right side, there was no significant difference between the extraction and nonextraction groups; however, there was a rise in length in the nonextraction and palatal expansion groups. On the left side, there was little change between the nonextraction and palatal expansion groups, but the extraction group had a modest increase in length. Mean lengths compared within three groups revealed insignificant difference.

Conclusion:

Palatal rugae pattern can be used in establishing identity in forensic medicine provided antemortem data are available. Orthodontic treatment has an impact on stability of palatal rugae. Most reliable and stable points being third rugae, they could be used as reference points to evaluate tooth movements

Frequency and variability of five non metric dental crown traits in the permanent maxillary dentitions of a racially mixed population from Bengaluru, Karnataka

INTRODUCTION

Evaluation of Tooth Crown non metric traits benefits to assess the biological distance between populations. It is well known that these traits are characterised by a high inter-population differentiation, low sexual dimorphism, and their recording is loaded by relatively small intra and inter observer error. The dental morphological traits are successfully used in the description and explanation of the microevolutionary and ethnogenetic processes. This paper presents the results of the permanent maxillary dentition tooth crown traits differentiation of human populations from Bengaluru.

MATERIALS AND METHODS

The comparative analysis was carried out on the basis of 4 groups for 5 Tooth Crown non metric traits in maxillary permanent dentition using Arizona State University Dental Anthropology System for morphological scoring system of each trait and each score was charted on Osteoware Dental Morphology software.

RESULTS

Study analysed 400 dental casts from 4 different ethnic groups. Traits Winging, shovelling, lingual tubercle showed highest expression in Iranians while Cusp of Carabelli's trait expression showed 87% of prevalence in the surveyed group but the Hypocone trait showed the highest expression in Muslims.

CONCLUSION

Traits of the human dentition can be a valuable diagnostic tool for anthropological studies in classifying and characterizing different ethnic groups. According to the results obtained from this study, it can be said that the groups Hindus, Muslims and Christians (Indians) belong to Sundonts, while Iranians fall under sinodonts population group.

Forensic odontology as a humanitarian tool

Humanitarian forensic action is the application of skills of forensic science in a conflicts or disasters as a humanitarian action. Forensic odontologist promote forensic odontology and forensic science principles to caseworks with the purpose of preventing human right violation by human identification, age estimation and where ever dental evidence is involved. Forensic odontologist is involved in all phases of disaster victim identification. According to Disaster Victim Identification Guide, if a positive match is found using dental identification it can be trusted as a standalone identifier. Dental structures are well protected and the hardest structure of the body. They resist decomposition and high temperatures and are the last one to disintegrate after death. Dental hard tissue provide abundant information in disaster victim identification, missing and unidentified persons, child abuse and neglect, domestic violence and sexual abuse with bite mark evidence, age estimation of unaccompanied minors, border control and human trafficking. The present article highlights the role of forensic odontologist in human identification for the purpose of preventing human rights violation.

Extracellular matrix in invasion and metastasis of oral squamous cell carcinoma

Oral squamous cell carcinoma is a common cancer in developing countries with highly invasive and metastasis credentials. The Lymphnode metastasis in oral squamous cell carcinoma is regarded as the factor that decides on disease survival of patients. Steps have been made towards research in the field of Oral squamous cell carcinoma for better understanding of the molecular events involved in invasion and metastasis. Recently, the role of Extracellular matrix (ECM) of oral squamous cell carcinoma in invasion and metastasis has gained interest, as ECM is known to actively contribute in events that regulate transcriptional controls and cell signalling mechanisms involved in invasion and metastasis. Understanding such contributing role of ECM may pave way for newer methodologies in early detection, prevention and therapeutic strategies for oral squamous cell carcinoma.

Ameloblastic carcinoma: A rare case with diagnostic dilemma

Ameloblastic Carcinoma is a rare malignant Odontogenic tumour with characteristic histopathology and clinical features which requires aggressive surgical treatment and surveillance and therefore differs from ameloblastoma. It is possible that ameloblastoma shows a variety of histologic and biologic behaviour ranging from benign to frank malignancy. Cases of ameloblastoma should thus be studied carefully, correlating their histologic pattern with biologic behaviour to direct subtle changes in histology that may predict the aggressiveness of the tumor. Thus the identifying features of Ameloblastic Carcinoma must be carefully known and recognized by dental professionals. The purpose of this article is to report a rare case of Ameloblastic Carcinoma and to highlight the clinical, radiological and variable histological features with possible differential diagnosis.

The cusp of Carabelli: Frequency, distribution and type in the Bengaluru population

AIMS

Detailed description and study of teeth traits could provide valuable information regarding phylogeny of man and distinctions between races and subraces. But morphological variations of the human dentition have not been utilized to their full potential by anthropologists concerned with patterns of human biological variation in Indian population. The aim of the present study is to detect the frequency and degree of expression of Carabelli's trait in Bengaluru population, this helps to develop a probabilistic model to distinguish individuals from specific human populations, particularly for forensic purposes.

MATERIALS AND METHODS

A total number 400of age and sex matched individuals from four different ethnic groups - Hindu, Islam, Christian and Iranians were examined clinically and study casts were made. Permanent maxillary first molars were examined for the expression of Carabelli's trait, Dahlberg classification system was used to score the trait on the teeth. The scores were recorded on Osteoware Dental Morphology software. The cast were examined by 2 observers independently to eliminate intra observer variation in interpretation and mean of 2 was taken for analysis. The data so obtained was statistically analysed especially emphasizing on differences between above mentioned 4 ethnic groups.

RESULTS

Cusp of Carabelli was present in 87% of the study population in maxillary first permanent molar. Type 3 was the most frequently expressed and Type 6 was the least frequently expressed and both type being expressed in Islamic groups. The expression of trait was bilateral in 90% of the surveyed groups.

CONCLUSIONS

It was concluded that the prevalence of cusp of Carabelli in the small population from Bengaluru considered in the present study was found to possess a high degree of Carabelli trait expression.

Mucormycosis in immunocompetent patient resulting in extensive maxillary sequestration

Mucormycosis or zygomycosis, also called phycomycosis, is an uncommon, invasive, potentially lethal and an aggressive fungal infection of the order Mucorales that usually affects patients with alteration of their immunological system. From its initial description (Paltauf, 1885), this entity still has a high mortality. Imaging techniques are not usually diagnostic, and cultures are not totally reliable. Definitive diagnosis is exclusively obtained by means of histopathological examination. Early recognition and aggressive treatment are of paramount importance and have reduced the mortality and morbidity. We present here a case report of oral mucormycosis in a 32-year-old male, immunocompetent individual resulting in extensive maxillary sequestration.

Prevalence of nasal carriers of methicillin-resistant Staphylococcus aureus among dental students: An in vivo study

Aim

The aim of this study is to evaluate the prevalence of nasal carriage of coagulase positive methicillin-resistant Staphylococcus aureus (MRSA) among dental students.

Materials and Methods

Four hundred dental students, divided into two groups - undergraduates (200) and postgraduates (200), were screened using sterile cotton swabs for carriage of MRSA in anterior nares. The samples were inoculated on HiCrome MeReSa Agar Base-with cefoxitin supplement. Further confirmatory tests were done by Gram-staining, Tube coagulase and Cefoxitin disc diffusion test on Mueller-Hinton agar.

Results

MRSA was positive among 25 (12.50%) undergraduates and 49 (24.50%) postgraduates students. Further confirmatory test also showed the same results. MRSA colonization was significantly more in postgraduate students, who are exposed to more number of patients and have put in more clinical hours as compared to undergraduate students who have just entered clinics and have limited clinical exposure.

Conclusion

The present study concluded that rate of MRSA colonization was 18.5% in the dental school population. The colonization rate was significantly (P = 0.002%) higher in postgraduate students as compared to undergraduate students emphasizing the need to follow infection control protocols stringently.

Clinical Significance

Awareness about MRSA among dental doctors is mandatory so as to prevent transmission of MRSA in dental settings.

Epigenetics in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common type of oral neoplasm, accounting for over 90% of all oral malignancies and 38% of head and neck tumors. Worldwide, OSCC is the eighth most common human cancer, with more than 500,000 new cases being diagnosed every year with a fairly onerous prognosis, encouraging further research on factors that might modify disease outcome. Genetic and/or environmental risk factors associated with the development of oral cancer have been sufficiently understood (smoking, alcohol, betel, diet, living habits, etc.). Knowledge of the genetic basis in oral carcinogenesis is still a challenging task. To improve the diagnosis and prevention, a previously unknown type of chromatin modification, known as epigenetic, which is defined as heritable DNA changes that are not encoded in the sequence itself and which are reversible and increasingly appear to serve fundamental roles in cell differentiation and development are studied. Tumors shed their DNA into the blood and epigenetic changes that occur early during tumorigenesis, sometimes even in premalignant lesions, can provide valuable biomarkers. Key components involved in epigenetic regulation are DNA methylation, histone modifications and modifications in micro ribonucleic acids (miRNAs). Epigenetic modifications may contribute to aberrant epigenetic mechanisms seen in oral precancers and cancers. In the near future, epigenetic variations found in oral dysplastic cells can act as a molecular fingerprint for malignancies.

Juxtaoral organ of Chievitz: An innocuous organ to be known

The Juxtaoral Organ of Chievitz is a normal anatomical structure located within the soft tissue in the buccotemporal fascia on the medial surface of the ascending ramus. This enigmatic vestigial structure is considered to be of neuroepithelial origin with no known function. As a matter of fact, JOOC is one of the most treacherous pitfalls in surgical pathology with respect to lesions in the head and neck area. Hence the basic aim of this short communication is to reveal the importance about this organ and enlighten the oral pathologist about this histopathological structure, thus preventing extensive and unnecessary investigations.

Immunohistochemical study of CD44s expression in oral squamous cell carcinoma-its correlation with prognostic parameters

BACKGROUND AND OBJECTIVES

The study aims at the observation of the immunohistochemical expression of CD44s in Oral Squamous Cell Carcinoma (OSCC) and to correlate its expression with prognostic parameters.

MATERIALS AND METHODS

A total of 30 cases of OSCC, - 10 cases of each well differentiated (WD SCC), moderately differentiated (MD SCC) and poorly differentiated squamous cell carcinomas (PD SCC) were included in the study. The sections were subjected to immunohistochemical study using CD44s antigen marker. The degree of intensity and distribution of CD44s immunostaining was assessed and correlated with prognostic markers such as tumor stage (tumor size), tumor grade (Broder's histological grading), tumor site, tumor thickness (histological depth of invasion) and nodal status.

RESULTS

CD44s expression by tumor cells in OSCCs is statistically correlated with tumor grade i.e. Higher mean of CD44s immunoexpression was observed in WD SCC group (10.80 ± 3.97), followed by MD SCC group (5.90 ± 3.38) and PD SCC group showed least CD44s immunoexpression (3.70 ± 4.64). There was no statistical significance observed with respect to the other prognostic markers.

CONCLUSION

Based on these observations it can be suggested that the decrease in expression of CD44s in OSCC cells may be due to the reduced cell-to-cell and cell-to-matrix adhesion, resulting in easy detachment from the rigid constitution. Low expression of CD44s in OSCC tissues may be an indicator of tumor invasion and high metastatic potential.

Immobilization of polyphenol oxidase onto mesoporous activated carbons -- isotherm and kinetic studies

Investigations were carried out in batch modes for studying the immobilization behavior of polyphenol oxidase (PPO) on two different mesoporous activated carbon matrices, MAC400 and MAC200. The PPO was immobilized onto MAC400 and MAC200 at various enzyme activities 5 x 10(4), 10 x 10(4), 20 x 10(4), 30 x 10(4)Ul(-1), at pH 5-8, and at temperature ranging from 10 to 40 degrees C. The intensity of immobilization of PPO increased with increase in temperature and initial activities, while it decreased with increase in pH. Immobilization onto MAC400 followed the Langmuir model while Langmuir and Freundlich models could fit MAC200 data. Non-linear pseudo first order, pseudo second order and intraparticle diffusion models were evaluated to understand the mechanism of immobilization. The free and immobilized enzyme kinetic parameters (K(m) and V(max)) were determined by Michaelis-Menten enzyme kinetics. The K(m) values for free enzyme, PPO immobilized in MAC400 and in MAC200 were 0.49, 0.41 and 0.65 mM, respectively. The immobilization of PPO in carbon matrices was confirmed using FT-IR spectroscopy and scanning electron microscopy.