cad a22 4500 551468432 20200417040220.0 cr unu---uuuuu 181215e20180507xx s 000 0 eng 10.5167/uzh-159468 doi 10.1186/s40510-018-0211-7 doi (ZORA)oai:www.zora.uzh.ch:159468 610 ddc 29732491 pmid Orthodontic bonding and debonding induces structural changes but does not alter the mechanical properties of enamel [Elektronische Daten] [Alexis Ioannidis, Spyridon N Papageorgiou, Iosif Sifakakis, Spiros Zinelis, George Eliades, Theodore Eliades] openAccess eu-repo BACKGROUND The purpose of the study is to investigate the effect of the bonding procedure on the mechanical properties of human enamel. METHODS A total of 20 extracted human premolars were included in this study, with the half of each tooth acting as its own internal control. Embedded and horizontally cut specimens were prepared, and two bucco-orally zones were separated. The first enamel zone of each tooth remained untreated. The opposing zone was subjected to simulated bonding and debonding, including etching with 37% phosphoric acid, bonding with primer and flowable composite resin, and subsequent removal of the composite with an adhesive removal bur. The properties tested were (a) elemental composition by energy-dispersive X-ray analysis, (b) mechanical properties of specimens by instrumented indentation testing (Martens hardness, elastic modulus, and elastic index), (c) enamel morphology by low-vacuum scanning electron microscopy, and (d) molecular composition by Raman microspectroscopy. Statistical analysis was performed by one-way mixed-effects analysis of variance at a = 0.05. RESULTS No significant differences could be found in the mechanical properties (Martens hardness, elastic modulus, and elastic index) and elemental composition of intact and treated enamel, with the possible exception of Si traces, which were found only in the latter. Raman analysis revealed no differences between the two surface states while shallow grooves and parallel lines were found on the surface of treated enamel by SEM analysis. CONCLUSIONS Under the limitations of the conditions of the study, there were no mechanical properties' alterations on enamel subjected to orthodontic bonding. Clinic for Orthodontics and Pediatric Dentistry zora Clinic of Reconstructive Dentistry zora Ioannidis Alexis joint author Papageorgiou Spyridon N. joint author Sifakakis Iosif joint author Zinelis Spiros joint author Eliades George joint author Eliades Theodore joint author Progress in Orthodontics 19:12 https://www.zora.uzh.ch/id/eprint/159468/2/s40510-018-0211-7_pub.pdf text/html WWW-Backlink auf das Repository 1 Journal Article PeerReviewed zora ZORA 856 40 https://www.zora.uzh.ch/id/eprint/159468/2/s40510-018-0211-7_pub.pdf text/html WWW-Backlink auf das Repository ZORA 700 1- Ioannidis Alexis joint author ZORA 700 1- Papageorgiou Spyridon N. joint author ZORA 700 1- Sifakakis Iosif joint author ZORA 700 1- Zinelis Spiros joint author ZORA 700 1- Eliades George joint author ZORA 700 1- Eliades Theodore joint author ZORA 773 0- Progress in Orthodontics 19:12 BK010053 XK010053 XK010000 ZORA ZORA ZORA Journal Article openAccess