Comparison of manual and physiologically molded denture bases in complete denture wearers

Background and Objectives: In complete denture wearers, the accumulation of food in the buccal vestibule is one of the factors causing discomfort to the patient. This study was conducted to evaluate the effect of mandibular denture buccal flange on food retention and to correlate between varying angulations of buccal flange of mandibular denture on food retention. Materials and Methods: Complete dentures were fabricated and the mandibular complete denture was duplicated. The existing (unduplicated) manually molded and physiologically molded dentures were tested for food retention. Twenty test particles having a diameter of 2±0.2 mm were placed on the middle part of the buccal flange and the subjects were instructed to expel the test particles by performing only functional movements of the buccal musculature. The numbers of residual test particles in the buccal vestibule were counted after 30s. The angulations of the denture buccal flange (duplicated) were measured with an optical bevel protractor and trimmed to 50° and the food retention test was performed. Similar tests were performed at 60°, 70° and 80° angulations. The data were evaluated using the Pearson correlation coefficient, One-way ANOVA test and Wilcoxon signed rank test. Results: The difference between the residual scores of manually molded and physiologically molded denture base was not significant. The difference between the residual scores at different angulations of the buccal flange of the denture was significant. Conclusion: Only the slope of the flange significantly affects the ability of subjects to expel the test particles

Effect of five brands of latex gloves on the setting time of polyvinyl siloxane putty impression materials

Addition silicone impression materials have been used as impression material for more than 20 years. Although they are among the most expensive impression materials, they became popular during the past decade as they have excellent physical properties. Prevention of infection is an important aspect in dental treatment since dental professionals are routinely exposed to the wide variety of microorganisms present in saliva. Gloves are the most common protective measure used during dental treatment. The gloves are mostly made of latex. In this study, we examine how the setting time of three types polyvinyl putty materials were affected by the use of five different brands of latex gloves and one brand of vinyl gloves. Each material was first mixed without wearing gloves according to the manufacturer′s instructions. After the stipulated mixing time, the setting time was measured using the Vicat needle. The setting time is measured from the time of mixing till the time that the needle does not produce any indentation on the surface of the material. The putty material was then mixed with gloved hands (using the five different brands of latex gloves in turn) and the setting time was measured. Then the material was mixed with washed gloved hands, and the setting time was measured again. Finally, the material was mixed with vinyl gloved hands and the setting time was measured. The following conclusions were drawn from the study: Reprosil™ and Express™ showed significant variation in the setting time with the latex gloved hands.There was no significant variation in the setting time when material was mixed with unwashed vs washed gloved hands.Vinyl gloves did not significantly affect the setting time of any of the putty impression materials

Application of Botulinum toxin Type A: An arsenal in dentistry

An extremely effective way of preventing damage to and enhancing treatment of dental hard tissues and restorations would be to ′′de-programme′′ the muscles responsible for excessive destructive forces and other gnathological-related diseases. The new paradigm is the intramuscular injection of Botulinum toxin type A (BOTOX) into the affected muscles. It is a natural protein produced by anaerobic bacterium, Clostridium botulinum. The toxin inhibits the release of acetylcholine (ACH), a neurotransmitter responsible for the activation of muscle contraction and glandular secretion, and its administration results in reduction of tone in the injected muscle. There are seven distinct serotypes of Botulinum toxin, viz., A, B, C, D, E, F, and G, which differ in their potency, duration of action, and cellular target sites. This paper describes the different applications of BOTOX in dentistry

A clinical study to compare between resting and stimulated whole salivary flow rate and pH before and after complete denture placement in different age groups

Purpose: This study compared the flow rate and pH of resting (unstimulated) and stimulated whole saliva before and after complete denture placement in different age groups. Materials and Methods: Fifty healthy, non-medicated edentulous individuals of different age groups requiring complete denture prostheses were selected from the outpatient department. The resting (unstimulated) and stimulated whole saliva and pH were measured at three stages i.e., Before complete denture placement; Immediately after complete denture placement; and After 2 to 3 months of complete denture placement. Saliva production was stimulated by chewing paraffin wax. pH was determined by using a digital pH meter. Results: Statistically significant differences were seen in resting(unstimulated) and stimulated whole salivary flow rate and pH obtained before, immediately after, and after 2 to 3 months of complete denture placement. No statistically significant differences were found between the different age groups in resting (unstimulated) as well as stimulated whole salivary flow rate and pH. Conclusion: Stimulated whole salivary flow rates and pH were significantly higher than resting (unstimulated) whole salivary flow rates and pH obtained before, immediately after, and after 2 to 3 months of complete denture placement. No age related variations in whole salivary flow rate and pH were observed in healthy, non-medicated individuals. Clinical Implications: The assessment of salivary flow rate, pH in different age groups is of prognostic value, which is an important aspect to be considered in the practice of removable prosthodontics