Objective: To conduct a systematic review on color stability of dental resin-based composites (RBC) exposed to conventional and electronic cigarettes. Materials and Methods: In vitro studies reporting on the color stability of RBC exposed to conventional cigarettes or to e-cigarettes: both Tobacco Heating Systems (THS) and Electronic Nicotine Delivery Systems (ENDS). The quality of the included studies was assessed with the QUIN tool (risk-of-bias tool for assessing in vitro studies conducted in dentistry). A systematic search, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed on four (n = 4) databases (Embase, Medline, Scopus, Web of Science) for articles published until March 28th, 2022.Results: Of the 365 screened articles, 13 were included in this review. All the included articles analyzed conventional cigarette smoke (CS), four analyzed Electronic Nicotine Delivery Systems (ENDS) and two Tobacco Heating Systems (THS). In terms of study design, smoke exposure time, smoke flow, type and number of cigarettes a high variability was reported. Conclusions:The available evidence suggests that CS smoke significantly affects color stability. Electronic cigarettes show less color change that seems to be easily recovered under clinical acceptability thresholds, although evidence is scarce.Clinical Significance: Clinicians should be aware, and should therefore warn their patients, that RBCs are subjected to irreversible color change if exposed to smoke. Electronic cigarettes (both ENDS and THS) induce less color change that can be recovered with repolishing or whitening procedures.

Objectives: To conduct a systematic review assessing quantitative enamel loss occurring after orthodontic debonding and clean-up procedures. Materials and Methods: A systematic search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was performed on different databases (Embase, Medline, Scopus, Web of Science) for papers investigating volumetric enamel loss due to bracket and clear aligner attachment debonding and/or clean-up procedures. Studies investigating in vivo and in vitro articles published in the English language until 16 July 2022 were included. The study selection was then performed by two authors who screened the abstracts independently. Results: Of 421 screened abstracts, 41 articles were selected for full-text analysis. Finally, nine studies were included in this review. No in vivo papers were retrieved. In vitro papers investigated volumetric loss caused by the removal of metal brackets (n = 7), ceramic brackets (n = 1), and both (n = 1). The clean-up procedure varied among all investigations. Impressions at baseline and after debonding/clean-up were superimposed, and the volumes were subtracted using different 3D digital analysis software. Among all included studies, the volumetric loss of enamel ranged from 0.02 ± 0.01 mm3 to 0.61 ± 0.51 mm3 per tooth. Conclusions: Debonding and clean-up procedures produce enamel loss. The debonding/clean-up procedure that is able to cause the least enamel volume loss has yet to be identified.