title: Enamel loss and adhesive remnants following bracket removal and various clean-up procedures in vitro.
abstract: This study evaluated the enamel loss and composite remnants after debonding and clean-up. The tested null hypothesis is that there are no differences between different polishing systems regarding removing composite remnants without damaging the tooth surface. Brackets were bonded to 75 extracted human molars and removed after a storage period of 100 hours. The adhesive remnant index (ARI) was evaluated. The clean-up was carried out with five different procedures: 1. carbide bur; 2. carbide bur and Brownie and Greenie silicone polishers; 3. carbide bur and Astropol polishers; 4. carbide bur and Renew polishers; and 5. carbide bur, Brownie, Greenie and PoGo polishers. Silicone impressions were made at baseline (T0) and after debonding (T1) and polishing (T2) to produce plaster replicas. The replicas were analysed with a three-dimensional laser scanner and measured with analytical software. Statistical analysis was performed with the Kruskal-Wallis test and pairwise Wilcoxon tests with Bonferroni-Holm adjustment (α = 0.05). Enamel breakouts after debonding were detectable in 27 per cent of all cases, with a mean volume loss of 0.02 mm(3) (±0.03 mm(3)) and depth of 44.9 μm (±48.3 μm). The overall ARI scores was 3 with a few scores of 1 and 2. The composite remnants after debonding had a mean volume of 2.48 mm(3) (±0.92 mm(3)). Mean volume loss due to polishing was 0.05 mm(3) (±0.26 mm(3)) and the composite remnants had a mean volume of 0.22 mm(3) (±0.32 mm(3)). There were no statistically significant differences in volumetric changes after polishing (P = 0.054) between the different clean-up methods. However, sufficient clean-up without enamel loss was difficult to achieve.
authors.affiliation: Departments of Orthodontics and Dentofacial Orthopedics, Klinik für Kieferorthopädie der Universität Bern, Freiburgstrasse 7, Bern, Switzerland. Ryf@zmk.unibe.ch
authors.forename: Sacha
authors.initials: S
authors.lastname: Ryf
authors.forename: Simon
authors.initials: S
authors.lastname: Flury
authors.forename: Senthamaraiselvi
authors.initials: S
authors.lastname: Palaniappan
authors.forename: Adrian
authors.initials: A
authors.lastname: Lussi
authors.forename: Bart
authors.initials: B
authors.lastname: van Meerbeek
authors.forename: Brigitte
authors.initials: B
authors.lastname: Zimmerli
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D017438:Bisphenol A-Glycidyl Methacrylate / Q000009:adverse effects / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D055117:Curing Lights, Dental; D001840:Dental Bonding / Q000379:methods; D003738:Dental Cements / Q000009:adverse effects / Q000737:chemistry*; D017005:Dental Debonding / Q000295:instrumentation / Q000379:methods*; D003743:Dental Enamel / Q000293:injuries / Q000473:pathology*; D003777:Dental Prophylaxis / Q000295:instrumentation / Q000379:methods; D018130:Diamond / Q000737:chemistry; D006801:Humans; D006813:Humidity; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007834:Lasers; D016910:Orthodontic Brackets / Q000009:adverse effects; D016628:Replica Techniques; D019279:Resin Cements / Q000009:adverse effects / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D017973:Tungsten Compounds / Q000737:chemistry
chemical_list: D017554:Carbon Compounds, Inorganic; D003738:Dental Cements; D019279:Resin Cements; D017655:Silicon Compounds; C477790:Transbond XT; D017973:Tungsten Compounds; C002802:tungsten carbide; C065742:Transbond; D017438:Bisphenol A-Glycidyl Methacrylate; D018130:Diamond; C022088:silicon carbide