Abrasive wear of bonding adhesives: Studies during treatment and after bracket removal

摘要: Abstract Two clinical experiments were performed to evaluate the rate of abrasive wear some commonly used bonding materials, all filled diacrylate resins. The first study was done on seven orthodontic patients. When four maxillary incisors bonded, excess material deliberately left around margin bracket bases. Bonding adhesives with submicron-size (0.2 0.3 μm) filler particles (adhesive E) and larger (average 10 30 μm), coarser fillers (adhesives C S) studied. three randomly divided between patients, so that any two them in same person. At time 3 6 months later, impressions taken positive replicas made. Stereomicroscopy scanning electron microscopy reduction and/or differences appearance adhesive. second experiment took place after debonding ten other persons. removal, residual adhesive purposely those teeth expected be most exposed tooth-brushing forces, namely, canines neighboring teeth. Studies this part restricted particles. A quick-etch technique (10 seconds) proved efficient revealing remnants their pattern. examined for presence at 1- 2-month intervals a period up 1 year. Standardized intraoral photographs each visit. Both demonstrated uniform somewhat surprising results abrasion materials apparently minimal. Around brackets (Experiment I), submicron slightly more smoothening surface irregularities than latter remained practically unchanged throughout periods observed. After II), showed clinically almost insignificant abrasion. Only very thin films reduced size or eliminated, while thicker layers no over 1-year observation (Figs. 8). As discussed, consequence minimal should great emphasis must paid use (1) focused active removal bases (2) which enamel is virtually free remnants.