Assessment of hygiene habits and attitudes among removable partial denture wearers in a university hospital.

AIMS: The aim of this study was conducting a survey of hygiene habits and use of removable partial dentures (RPDs) and correlate them with the social conditions of the interviewees. METHODS: A total of 145 RPD wearers were interviewed by experienced clinical staff using a structured questionnaire. A Chi-squared test was performed to evaluate statistical significance between the variables, and the level of significance was P<0.05. RESULTS: A total of 72 (49%) patients reported that they had not been well informed by the dentists. Brushing was the most frequent cleaning method (57.6%). 77 (53.1%) patients did not take off their dentures at night. The frequency of cleaning dentures and using cleansing tablet was significantly higher in females than in males (P<0.05). The frequency of denture cleaning, cleaned parts of denture, use of cleansing tablet, removal of dentures at night, frequency of tooth brushing, does not show any significant difference according to age, educational status or duration of denture usage (P>0.05). RPD wearers did not clean their dentures and natural teeth satisfactorily and had limited knowledge of denture cleansing and oral hygiene maintenance. CONCLUSIONS: Hygiene habits and attitudes may be affected by gender, but education level and hygiene attitudes may not always present positive correlation. Dentists should thoroughly inform patients about the harmful effects of overnight wearing and motivate to clean metal parts of RPD's and cleansing tablet use in order to minimize the abrasive effect of widely preferred cleaning method of brushing with toothpaste.

The effect of bleaching agents on the color stability of ceromer and porcelain restorative materials in vitro.

PURPOSE: The aim of this in vitro study was to determine the color changes of five different restorative materials after exposing these materials to two different home bleaching agents. METHODS: This study applied bleaching agents to an ultralow-fusing porcelain, a low-fusing porcelain, two types of heat-pressed glass ceramics, and a ceromer. A total of 24 disc-shaped specimens were fabricated (with a diameter of 10 mm and a thickness of 2 mm) from each material (n=12). The initial color measurements were taken with a spectrophotometer. The first set of specimens were bleached with 10% hydrogen peroxide (HP) for one hour daily for 10 days. The other set of specimens were bleached with 10% carbamide peroxide (CP) bleaching gel for eight hours daily for 14 days. Data were analyzed with the one-way analysis of variance and Kruskal-Wallis statistical test. The difference in the prebleaching and postbleaching color of each material was considered to be statistically significant at p < 0.05. RESULTS: The study found a statistically significant difference among the color changes of the test groups after exposing them to both bleaching agents (p<0.05). Appreciable color change was observed in the Estenia (ΔE=3.99) specimens that were bleached with the HP, and noticeable color changes were observed in the Estenia (ΔE=1.89) and IPS Empress 2 (ΔE=1.66) groups when they were treated with the CP. CONCLUSIONS: Restorations (especially polymer-containing restorative materials) should be protected before any bleaching procedure due to the high risk of color change.