Plastination - A method for preservation of oral hard and soft tissue biopsy specimen v/s the conventional method of preservation with formalin.

Context: Plastination is one of the most advanced method for preserving perishable biological specimen as well as tissue samples as for a longer period of time using polymers. Aims: To evaluate the changes in dimension of hard and soft tissue specimens after plastination procedure and compare it with the conventional method of preservation in formalin. Settings and Design: Institution-based retrospective study. Methods and Material: The study included 20 formalin-fixed soft tissue and 10 formalin-fixed hard tissue specimens. All the specimens were plastinated which involved four basic steps of fixation, dehydration and defatting, impregnation with polymer and curing of polymer followed by finishing and storage. The specimens were analysed for shrinkage and dimensional changes and changes in colour and consistency between formalin-fixed specimen and plastinated soft tissue and hard tissue specimen. Statistical Analysis Used: Descriptive statistics were used. Results: After plastination, soft tissues showed average shrinkage of 3.49%with a range of 0.80-7.90% in comparison to the original size. In case of teeth and hard tissue specimen, there was no evidence of dimensional changes or shrinkage before and after plastination. Changes in colour and consistency of the soft tissue specimens were also noted before plastination and after plastination. Conclusions: Although the plastinated specimens in the current study showed minimal shrinkage rate, they have proved to be an excellent alternative to formalin-fixed specimens as they are easy to handle and maintain, non-infectious, non-toxic, user-friendly.

Non-Invasive Saliva-based Detection of Gene Mutations in Oral Cancer Patients by Oral Rub and Rinse Technique.

BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) is the most widely reported cancer worldwide. Liquid biopsy, a method that relies on identification of tumor-associated cells and/or cell free nucleic acids from body fluids is becoming increasingly popular in cancer diagnostics. The aim of the study was to evaluate the feasibility of Oral Rub and Rinse (ORR) technique in determining the genetic changes in common biomarkers of oral cancer such as TP53 using DNA obtained from saliva of oral cancer patients. METHODS: A total of 15 oral cancer patients were recruited in the study and pre-surgical saliva samples were collected using the ORR technique. Tissue samples included in the study were obtained during the surgical excision of the cancerous oral lesion. Genomic DNA was isolated from the salivary cell plug and the tissues and the TP53 gene was amplified by PCR. The PCR products of all the exons of TP53 (Exons 2 to 11) were electrophoresed on agarose gel, purified and sequenced by Sanger method. The obtained sequences were compared with the reference sequence of TP53 gene. STATISTICAL ANALYSIS USED: Descriptive statistics were used and reported as frequency and percentage. RESULTS: Capillary sequencing of TP53 gene from tissue DNA revealed the presence of codon 72 c.215C>G (p.Pro72Arg) polymorphism in 10 patients (67%) and a heterozygous mutation at codon 172 c.514 G>T (p.Val172Phe) in 2 patients (13%). Among the 10 samples that showed codon 72 polymorphism, matched salivary DNA was available for 6 samples and 4 out of these showed same genetic change at codon 72. Similarly, of the 3 samples that showed codon 172 mutation, matched salivary DNA was available for 1 sample and the mutation status was identical. CONCLUSION: The results suggest a potential for clinical applications of ORR technique as an alternative to invasive tissue biopsy for detection of genetic changes in candidate biomarkers in oral cancer.

Non-invasive detection of EGFR mutations by cell-free loop-mediated isothermal amplification (CF-LAMP).

Targeting epidermal growth factor receptor (EGFR) through tyrosine kinase inhibitors (TKI) is a successful therapeutic strategy in non-small cell lung cancer. However, the response to TKI therapy depends on specific activating and acquired mutations in the tyrosine kinase domain of the EGFR gene. Therefore, confirming the EGFR status of patients is crucial, not only for determining the eligibility, but also for monitoring the emergence of mutations in patients under TKI therapy. In this study, our aim was to develop a cost effective, yet sensitive, technique that allows the detection of therapeutically-relevant EGFR hotspot mutations at isothermal conditions in a non-invasive manner. Previously, we developed an allele-specific loop-mediated isothermal amplification (AS-LAMP) assay for screening germline and somatic de novo T790M EGFR mutation in lung cancer patients. In this study, we used cell free DNA as a template in AS-LAMP assay (CF-LAMP) for non-invasive detection of two hotspot EGFR mutations (T790M, and L858R) and compared its efficiency with ultrasensitive droplet digital PCR (ddPCR) assay. The results of CF-LAMP assay were consistent with those obtained in ddPCR assay, indicating the robustness of the method. CF-LAMP may serve as a valuable and cost-effective alternative for liquid biopsy techniques used in molecular diagnosis of non-small cell lung cancer.

Salivary lactate dehydrogenase as a prognostic marker in oral squamous cell carcinoma patients following surgical therapy.

OBJECTIVE: The objective of the present study was to assay the salivary levels of lactate dehydrogenase in patients with OSCC in comparison to healthy controls and to assess the changes in salivary levels of lactate dehydrogenase as prognostic markers of surgical therapy in oral squamous cell carcinoma patients. A case control study was undertaken comprising of 20 patients who were clinically diagnosed and histopathologically proven with oral squamous cell carcinoma and compared with 20 age and gender matched controls. Unstimulated whole saliva (2 ml) was collected by the spit method from every subject. The salivary LDH levels were analysed before surgery (baseline value) and compared with the control group. One month following surgical therapy, the salivary LDH levels were measured again and compared with the baseline values. The results obtained were subjected to statistical analysis using one way ANOVA and Pearson's correlation. The results of the present study showed that the mean salivary LDH levels in the study and control group were 457.06 ± 88.93 IU/L and 178.35 ± 120.54 IU/L respectively, the difference of which was statistically significant (p<0.001). Comparison of salivary LDH levels before surgery and 1 month after surgery showed that there was a decrease of salivary LDH levels, one month after surgical therapy, the difference of which was statistically significant (p<0.001). The study concluded that salivary lactate dehydrogenase levels could be used not only as a diagnostic marker but it could also be a valuable prognostic biomarker in patients treated surgically for OSCC.

Histopathological differentiation of oral squamous cell carcinoma and salivary lactate dehydrogenase: A biochemical study.

CONTEXT: Early diagnosis of oral cancer is a priority health objective, in which oral health professionals may play a pivotal role. Detection should lead to less damage from cancer therapy and to a better prognosis. AIMS: The aim was to estimate and compare the salivary lactate dehydrogenase (LDH) levels in various histological differentiation of oral squamous cell carcinoma (OSCC) patients and normal subjects. SETTINGS AND DESIGN: Hospital-based setting, case-control study. SUBJECTS AND METHODS: A case-control study was undertaken comprising 30 OSCC patients and 30 healthy controls. The OSCC patients were grouped into well-differentiated, moderately differentiated and poorly differentiated OSCC based on their histological tumor differentiation. Unstimulated whole saliva was collected, assayed for LDH levels using a standard kit and measured spectrophotometrically at 340 nm. STATISTICAL ANALYSIS USED: The results obtained were subjected to statistical analysis using Kruskal-Wallis and Mann-Whitney U-tests. Spearman's correlation was used to correlate the histological tumor differentiation with the salivary LDH levels. RESULTS: The mean salivary LDH levels in the control group, well-differentiated OSCC group, moderately differentiated OSCC group, and poorly differentiated OSCC group were 117.33 ± 19.37 IU/L, 355.83 ± 16.73 IU/L, 484.18 ± 25.84 IU/L, and 620.35 ± 18.69 IU/L, respectively. The difference in the mean salivary LDH levels was statistically significant among the various groups (Kruskal-Wallis χ(2) = 50.820, P < 0.001). Spearman's correlation showed significant difference between salivary LDH levels and histological differentiation of OSCC (r = -0.689, P < 0.01). CONCLUSIONS: The salivary LDH levels were higher in OSCC patients when compared to the healthy controls. The salivary LDH levels were found to be the highest among the poorly differentiated OSCC.

Knowledge, attitude and practice regarding oral health among the rural government primary school teachers of Mangalore, India.

PURPOSE: This study was conducted to assess the knowledge, attitude and practice regarding oral health among the Rural Government Primary school teachers of Mangalore, Karnataka, India. METHODS: A self-administered close ended questionnaire consisting of 16 items was distributed among the rural primary school teachers of Mangalore (n=165). Comparison of knowledge and attitude amongst the 3 age groups was done with Kruskal Wallis test. Comparison of mean scores between the genders was done using Mann-Whitney-U test. Comparison of mean scores across four educational qualification groups was done using Kruskal Wallis test. RESULTS: Out of 165 primary school teachers to whom the questionnaires were sent, 153 responded, yielding a 92.7% response rate. Results showed that significant difference (p<0.01) was seen across the 3 age groups for the mean practice scores. There was significant difference between the genders with females scoring better for the mean knowledge, practice and the total scores. Educational qualification did not make any significant difference in the knowledge and practice on oral health. CONCLUSION: The study concluded that oral health knowledge was lacking among the primary school teachers of rural Mangalore, although practices were satisfactory. Oral health education program targeting only the teachers is of utmost importance in the light of the present study results.

Oral hygiene practices among paramedical staff of a private dental institution in India

Introduction: Health promotion in dentistry is targeted at the two most common oral diseases - dental caries and periodontal disease. The maintenance of good oral hygiene is considered to be a central issue in oral health promotion. Objective: To assess the oral hygiene practices among paramedical staff of a private dental institution in India. Material and methods: A cross sectional questionnaire survey was undertaken among 100 paramedical staff of a private dental institution in Mangalore, India. Data was collected by using self designed questionnaire. Results: About 49% of the subjects brushed thrice with soft toothbrush and 55% changed their tooth brush once in 3 months. About 77% of them cleaned their tongue either by tongue cleaner, toothbrush or finger and 82% of the subjects used tooth paste. About 56% of the subjects had never used dental floss. Majority of the subjects (56%) visited the dentist only when required. Conclusion: Oral hygiene practices among the paramedical staff were poor.

Health literacy among Indian adults seeking dental care.

BACKGROUND: Poor literacy can impede one's ability not only to seek out needed health information but also to process, understand and use it to make appropriate health care decisions. The objective of the study was to assess the health literacy among adult patients seeking oral health care at in a private dental hospital in Bangalore, Karnataka, India. MATERIALS AND METHODS: A cross sectional questionnaire survey was carried out on 500 subjects. The questionnaire designed by Chew and colleagues (2004) was modified and used as the survey instrument. To be eligible to participate in the study, the participants had to be aged above 18 years and able to read or write English/Kannada (local language). Analysis of variance (ANOVA) and Student's t-test (two tailed, independent) was used to find the significance of study parameters at 95% confidence interval. RESULTS: About 60.4% of the subjects had low health literacy level, 29.4% average and only 10.2% had high health literacy levels. Age and educational qualification had a suggestive significant difference with the mean health literacy scores while gender did not have any significant difference. Subjects who had completed post-graduation (57.8%) too had low health literacy levels. CONCLUSION: A large number of patients have low levels of health literacy that may interfere with their ability to process and understand basic health information.

Large Complex Odontoma: A report of a rare entity.

Odontomas are hamartomatous lesions composed of mature enamel, dentin, and pulp, and may be compound or complex depending on the extent of morphodifferentiation or on their resemblance to normal teeth. They are the most common benign odontogenic tumours, constituting 22% of all odontogenic tumours of the jaw. They are often non-aggressive and slow growing in nature, and are usually diagnosed on routine radiological examinations in the second decade of life. We report the case of an unusually large, painless, complex odontoma, which is a rare entity. It was located in the left posterior mandible and was associated with missing 1(st) and 2(nd) left mandibular molars. The diagnosis was confirmed following surgical excision and histopathological analysis of the lesion.