Comparative evaluation of masticatory efficiency in various facial forms of dentate and rehabilitated complete denture patients.

PURPOSE: To evaluate the masticatory efficiency in various facial forms of dentate and rehabilitated complete denture patients. MATERIALS AND METHODS: A total of 60 subjects were selected for the study based on the inclusion criteria. Out of which 30 subjects belong to the dentate group (D) and 30 subjects belong to the completely edentulous group rehabilitated with conventional complete denture (CECD). They were sub-grouped as brachyfacial, mesofacial, and dolichofacial facial form using facial index measurement and cephalometric analysis. After which they had undergone masticatory efficiency test using spectrophotometric analysis using diluted expectorate of chewed natural test food beetroot (10, 15 and 20 strokes). Mean of absorbance value obtained was considered as mean masticatory efficiency. From which average masticatory efficiency percentage was determined using masticatory efficiency percentage equation and considered as the masticatory efficiency of that particular subject. RESULTS: Statistical analysis reveals that among dentate subject (D) group, brachyfacial subjects exhibited highest masticatory efficiency (70.9 ± 12.64 %) followed by mesofacial (60.6 ± 10.66 %) and dolichofacial (34.3 ± 10.81%) subjects. Similarly in completely edentulous subjects rehabilitated with conventional complete denture (CECD), brachyfacial (52.7 ± 8.11%) subgroups, mesofacial (42.3 ± 6.52%) and dolichofacial (29.3 ± 7.76 %). CONCLUSION: Along with other determinant factors, facial form also plays an influential role on masticatory efficiency. Brachyfacial subjects exhibited highest masticatory efficiency followed by mesofacial and dolichofacial subjects among both the study groups.

Comparative evaluation of the antibacterial activity of red diode laser therapy and 0.2% chlorhexidine against Aggregatibacter actinomycetemcomitans on implant healing abutments: An ex vivo study.

Aims: The intraoral microbiota has a high potential to undergo dysbiosis, causing inflammatory changes with respect to the tissues surrounding either a natural tooth or an implant. Thus, the longevity of implant prosthesis depends on a thorough implant decontamination protocol. Among all the techniques available for doing so, laser is garnering increasing popularity, owing to minimal bleeding, high efficiency, and faster healing. However, limited literature exists regarding the superiority of lasers over chlorhexidine (CHX), the indisputable gold standard antibacterial chemical agent. The aim of this study was to compare the percentage of bacterial reduction of Aggregatibacter actinomycetemcomitans from implant healing abutments post red diode laser therapy versus 0.2% CHX treatment. Settings and Design: The current study had an ex vivo, observational, case-control design. Materials and Methods: Patients reporting for the second stage of the implant surgery were taken as the source of data and the healing abutments, the clinical samples. Eleven patients were chosen with one intraoral implant serving as the test site for laser treatment and another, the control site for CHX treatment. Microbiological analysis was performed via quantitative real time polymerase chain reaction to compare the bacterial reduction percentage after each treatment. Statistical Analysis Used: Repeated measures ANOVA and independent sample t test were used. Results: The mean bacterial viability of the test group (laser) was 1.2%-1.6%, and 0.6%-1.4% for the control group (CHX). The former caused a mean bacterial reduction of 96.1% while the latter, 96.3%. Both the treatments caused a highly statistically significant reduction of viable bacterial counts (P = 0.001). However, when compared, there was no statistically significant difference in the bacterial reduction, when compared in between the two (P = 0.902). Conclusion: Laser treatment is at par with chemical implant surface decontamination. It can help bypass the complications of CHX and revolutionize the protocols for implant surface decontamination.

Influence of Domestic Exposure to Polycyclic Aromatic Hydrocarbons on Women's Periconceptional Stage and Associated Risk of Oral Cleft in Offspring.

Background: Polycyclic aromatic hydrocarbons (PAHs) constitute a group of chemicals with an omnipresence in the environment and our surroundings. With their genotoxicity and carcinogenic nature, it has been proven to be monstrous in our daily life and, especially for pregnant women and their newborn. Aim: This questionnaire study was done to verify the influence of domestic exposure to polyaromatic hydrocarbons on women's periconceptional stage and risk of oral cleft in offspring in the suburban and the rural population of Mysore. Methodology: Two hundred pregnant women as patients from four different hospitals in Mysore were given a questionnaire to be filled with 24 parameters ranging from the knowledge to various means of exposure to the pregnant women with the PAH and the severity and the extent of the orofacial defect in the newborn. Results: It was determined that exposure of pregnant women to the smoke emanating from the method of cooking or heating to smoking (first or passive) and the direct inhalation of gas had the maximum effects on the association of cleft palate (60.7%) in unilateral followed by 90.9% in bilateral, 65.0% in soft tissue, and 76.2% in hard tissue cleft palate. Conclusion: The deleterious effects of the cooking and water heating measures practiced in the suburban and the rural population predisposed the pregnant women to significantly higher chances of offspring with the varied extent of the orofacial defect. There is an influence of domestic exposure to polycyclic aromatic hydrocarbons on women's periconceptional stage and risk of oral cleft in offspring.

Marginal and internal fit evaluation of conventional metal-ceramic versus zirconia CAD/CAM crowns.

BACKGROUND: The purpose of this in vivo study was to compare the marginal and internal gap widths of monolithic zirconia crowns fabricated by CAD/CAM technique and metal-ceramic crowns fabricated by conventional technique. MATERIAL AND METHODS: 10 participants needing a single restoration were selected. Zirconia crowns using CAD/CAM technology (Group A) (n=10) and metal-ceramic crowns (Group B) (n=10) using lost wax casting technique were fabricated for each selected tooth. The marginal and internal gaps of crowns were recorded using a replica technique with light body silicone material stabilized with a regular set putty. Each replica was sectioned buccolingually and mesiodistally and then evaluated at five pre-determined sites. The points measured were PM for marginal gap, PA for axial gap, PAO for axio-occlusal transition gap and PO and PCO for occlusal gaps using a stereomicroscope at 30× magnification. The Paired Sample (t) test was used to detect significant differences between the two groups in terms of marginal and internal fit (α= 0.05). RESULTS: The mean for the marginal gap was 77.42µm (±39.5µm) for Group A compared with 95.86µm (±55.12µm) for Group B. Mean values for internal gap was 87.24 (±21.7 µm) for Group A and 132.91 µm (± 50.63 µm) for Group B. Significant differences were observed between both the groups for marginal (p=.010) and internal (p=.000) fit. CONCLUSIONS: The CAD/CAM fabricated zirconia crowns demonstrated a better accuracy of fit when compared to metal-ceramic crowns fabricated by conventional technology. Key words:Marginal fit, Internal fit, Computer-aided design/computer-aided manufacturing (CAD/CAM).

Identification of rice landraces with promising yield and the associated genomic regions under low nitrogen.

With the priority of the low input sustainable rice cultivation for environment friendly agriculture, NUE of rice becomes the need of the hour. A set of 472 rice genotypes comprising landraces and breeding lines were evaluated for two seasons under field conditions with low and recommended nitrogen and >100 landraces were identified with relative higher yield under low nitrogen. Donors were identified for higher N uptake, N translocation into grains and grain yield under low N. Grains on secondary branches, N content in grain and yield appears to be the selection criterion under low N. Through association mapping, using minimum marker set of 50 rice SSR markers, 12 genomic regions were identified for yield and yield associated traits under low nitrogen. Four associated genomic regions on chromosomes 5, 7 and 10 were fine mapped and QTL for yield under low N were identified from the marker delimited regions. Three candidate genes viz., 2-oxoglutarate /malate translocator (Os05g0208000), alanine aminotransferase (Os07g0617800) and pyridoxal phosphate-dependent transferase (Os10g0189600) from QTL regions showed enhanced expression in the genotypes with promising yield under low N. Marker assisted selection using SSR markers associated with three candidate genes identified two stable breeding lines confirmed through multi-location evaluation.

Efficacy of commercial and household denture cleansers against Candida albicans adherent to acrylic denture base resin: an in vitro study.

AIM: To evaluate and compare the efficacy of two commercial and two household denture cleansers against Candida albicans adherent to acrylic denture base resin. MATERIALS AND METHODS: Fifty specimens of acrylic denture base resin (10 × 10 × 2 mm) were fabricated and processed according to the manufacturer's instructions. Sterile acrylic resin specimens were inoculated by immersing in Sabouraud broth containing C albicans for 16 hours at 37°C in an incubator. Then the specimens were washed and immersed in denture cleansers (four groups) - Clinsodent (powder form), Fittydent (tablet form), vinegar (4% acetic acid), diluted vinegar (50% diluted with water), and water (control group) for 8 hours at room temperature. After 8 hours the acrylic resin specimens were washed, fixed with methanol, and stained with crystal violet. Candida cells adherent to the acrylic resin specimens were counted under microscope. The number of cells adherent to the test samples were compared with that adherent to the control. STATISTICAL ANALYSIS: The data were analyzed using the independent-samples 't ' tests, analysis of variance (ANOVA), and Tukey's HSD test. RESULTS: All the denture cleansers were highly effective against C albicans. The effectiveness of commercial denture cleansers was significant better than that of household denture cleansers. Fittydent fared better than Clinsodent, but the difference between the two was not statistically significant (P=.765). Vinegar was more effective than diluted vinegar (P<.05). CONCLUSION: Within the limitations of this in vitro study, denture cleansers were found to be effective in reducing C albicans cells adhering to dentures. The commercial denture cleansers (Fittydent and Clinsodent) were more effective than household denture cleansers (vinegar and diluted vinegar).

Orientational and rotational velocity correlation functions for water-hydrating B- and Z-DNA double helices.

The molecular dynamics simulations reported earlier for the structure and dynamics of water molecules hydrating B- and Z-DNA double helices are analyzed for the orientational correlation functions and the proton rotational velocity autocorrelation functions. The spectra of the rotational velocity autocorrelation functions obtained from the simulation results are compared with the neutron inelastic scattering experiments on hydrated Na-DNA samples. The results predict a small frequency component associated with water molecules bound to the double helices that disappears for waters away from the double helix.

Acute otitis media in children: are decongestants or antihistamines necessary?

This study was designed to investigate the efficacy of a decongestant-antihistamine preparation in combination with antibiotic treatment of acute otitis media. The effectiveness of a new Dimetapp (DIM) preparation was assessed in comparison with each of its components (brompheniramine maleate [BPM] and phenylephrine hydrochloride [PEH] as well as a placebo (PL) vehicle in the treatment of acute otitis media. In a randomized double blind study, 98 children were treated in the emergency department or outpatient medical clinics at Children's Hospital of Michigan with amoxicillin and either DIM, BPM, PEH, or PL. They were evaluated at two weeks by clinical examination, pneumatoscopy, and tympanometry. Fifty-eight patients (59%) continued to have evidence of fluid in the middle ear. These patients were continued on the test medications for another two weeks and then reevaluated. There were significant differences between the treatment groups (DIM, BPM, and PEH) and the control PL group; the patients receiving Dimetapp or placebo fared better than those receiving BPM or PEH. However, there was no difference in the overall response between Dimetapp and placebo. Antihistamine-decongestant therapy does not appear to be necessary in the treatment of acute otitis media in children.