ObjectivesThis study evaluated the effect of lactic acid and acetic acid on the microhardness of a silorane-based composite compared to two methacrylate-based composite resins.Materials and MethodsThirty disc-shaped specimens each were fabricated of Filtek P90, Filtek Z250 and Filtek Z350XT. After measuring of Vickers microhardness, they were randomly divided into 3 subgroups (n = 10) and immersed in lactic acid, acetic acid or distilled water. Microhardness was measured after 48 hr and 7 day of immersion. Data were analyzed using repeated measures ANOVA (p < 0.05). The surfaces of two additional specimens were evaluated using a scanning electron microscope (SEM) before and after immersion.ResultsAll groups showed a reduction in microhardness after 7 day of immersion (p < 0.001). At baseline and 7 day, the microhardness of Z250 was the greatest, followed by Z350 and P90 (p < 0.001). At 48 hr, the microhardness values of Z250 and Z350 were greater than P90 (p < 0.001 for both), but those of Z250 and Z350 were not significantly different (p = 0.095). Also, the effect of storage media on microhardness was not significant at baseline, but significant at 48 hr and after 7 day (p = 0.001 and p < 0.001, respectively). Lactic acid had the greatest effect.ConclusionsThe microhardness of composites decreased after 7 day of immersion. The microhardness of P90 was lower than that of other composites. Lactic acid caused a greater reduction in microhardness compared to other solutions.

ObjectivesThis study aimed to assess the effect of 38% carbamide peroxide on the microleakage of class V cavities restored with either a silorane-based composite or two methacrylate-based composites.Materials and MethodsA total of 96 class V cavities were prepared on the buccal surface of extracted human teeth with both enamel and dentin margins and were randomly assigned into three groups of Filtek P90 (3M-ESPE) + P90 system adhesive (3M-ESPE)(group A), Filtek Z250 (3M-ESPE) + Adper Prompt L-Pop (3M-ESPE)(group B) and Filtek Z350XT (3M-ESPE) + Adper Prompt L-Pop (group C). Half of the teeth were randomly underwent bleaching (38% carbamide peroxide, Day White, Discus Dental, applying for 15 min, twice a day for 14 day) while the remaining half (control) were not bleached. Dye penetration was measured following immersion in basic fuchsine. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests at a level of 0.05.ResultsNo significant differences were found between composites in the control groups in enamel (p = 0.171) or dentin (p = 0.094) margins. After bleaching, microleakage of Z250 (in enamel [p = 0.867] or dentin [p = 0.590] margins) and Z350 (in enamel [p = 0.445] or dentin [p = 0.591] margins) did not change significantly, but the microleakage of P90 significantly increased in both enamel (p = 0.042) and dentin (p = 0.002) margins.ConclusionsNo significant differences were noted between the bleached and control subgroups of two methacrylate-based composites in enamel or dentin margins. Microleakage of silorane-based composite significantly increased after bleaching.

Although accuracy and reproducibility of the LF method were higher than those of the VI and BW radiography, it is better to use this method together with other methods to reduce diagnostic faults.

Context:Addiction results in a range of health problems especially in the oral cavity.Aims:This study assessed the oral health status among women with a history of drug abuse in Tehran, Iran.Settings and Design:A cross-sectional study was conducted through structured interviews and clinical examinations of women at three rehabilitation centers in Tehran.Materials and Methods:Data on background characteristics, addiction history, knowledge, attitudes and behaviors, and oral health indices were collected.Statistical Analysis Used:We used MANOVA test and multiple logistic regression models to analyze the data.Results:We assessed 95 participants aged 37.88 ± 10.65 years. The most commonly reported drugs used prior to treatment were opiates (77.2%). The mean knowledge and attitude score among the patients was 80.83 ± 12.89 (37.5–100). Less than half of the dentate women reported tooth brushing as “rarely or never” (44.2%). Most of them (81.8%) had never used dental floss and 76.1% were daily smokers. The mean score of dental caries index (decayed, missed and filled teeth) of the participants was 20.2 ± 7.18 and 17 subjects were edentulous (17.9%). Factors such as age, drug type, duration of addiction, time of last dental visit, and frequency of brushing were associated with oral health status among these women.Conclusions:Women with a history of drug abuse in our study suffered from poor oral health. Although they had an acceptable level of knowledge and attitude toward oral health, their oral health, and hygiene was poor. These results call for more attention in designing and implementing oral health programs for addicts.