Influence of Diode Laser for the Treatment of Dentin Hypersensitivity on Microleakage of Cervical Restorations.

Noncarious cervical lesions (NCCLs) are a common clinical finding often linked with dentin hypersensitivity (DH). Aim. The aim of the study was to evaluate the influence of diode laser for the treatment of DH on microleakage of subsequent NCCL restorations. Materials and Methods. Forty-eight extracted human premolars were collected. All teeth received standardized cervical preparation on both the buccal and palatal surfaces and were randomly divided into three groups (n = 16) according to the restorative material used: nanohybrid composite resin (CR), resin-modified glass ionomer (RMGI), and conventional glass ionomer (GIC). The prepared cavities on the palatal surfaces were treated by diode laser using SIROlaser Blue (Sirona Dental Systems, Bensheim, Germany) prior to restoration, while preparations on the buccal surfaces were directly restored. After thermocycling, the teeth were immersed in methylene blue dye for microleakage evaluation under 40x magnification at both occlusal and cervical margins. The Kruskal-Wallis test followed by the Bonferroni tests was conducted to determine inter- and intragroup differences (P < 0.05). Results. All restorative materials tested showed some degree of microleakage with no statistically significantly different scores with or without the use of laser desensitization prior to restorative treatment. Group CR showed the least microleakage, followed by group RMGI, while group GIC showed the highest. Cervical margins showed greater microleakage than the occlusal margins where the difference was statistically significant in the RMGI group without laser pretreatment (P = 0.006) and in both groups CR (P = 0.02) and RMGI (P = 0.006) with the laser pretreatment. Conclusion. Application of diode laser for the treatment of DH prior to the restoration of teeth with NCCL did not affect the microleakage of all the restorative materials tested. All the materials showed some degree of microleakage, which was higher in gingival margins compared to occlusal margins. The resin composite shows the least microleakage among all the tested materials.

Ergonomics of preclinical dental students and potential musculoskeletal disorders.

INTRODUCTION: Dental ergonomics aim to improve the safety and efficiency of dentists, reducing possible occurrence of musculoskeletal disorders (MSDs). Factors affecting dental ergonomics include gender, tooth position, and use of equipment such as magnifying loupes. Since work habits are acquired early during undergraduate dental training, it is essential to assess the ergonomics of students at the preclinical training level. OBJECTIVES: The present study aimed to assess the ergonomics of preclinical dental students in different clinical settings and their correlation to potential MSDs. METHODS: Student posture was assessed during preclinical restorative training using the Dental Ergonomics Assessment rubrics visual scale. The variables tested were use of magnification, gender, and tooth position. Musculoskeletal (MS) pain was reported using a questionnaire. Results were analyzed statistically using Mann-Whitney U test and Wilcoxon t-test (P < 0.05). Spearman test was used to determine the correlation between posture and pain. RESULTS: Use of magnification and tooth position significantly affected student posture. Female students had worse posture in certain clinical situations. Reported MS pain positively correlated with poor posture. CONCLUSION: The use of magnifying loupes could have a positive impact on the ergonomics of dental students during their preclinical training, possibly decreasing the risk of developing MSDs.