Effects of titanium brushes on different implant surfaces: an in vivo investigation

BACKGROUND: Recently, rotating brushes with titanium bristles have been introduced for the debridement of implant surfaces when peri implant problems occur. This study inves- tigated the effects induced by titanium brushes on different implant surfaces previously contaminated in vivo METHODS: n°9 disks, going sterilized directly from manu- facturer, (Megagen Implant Co, Ltd, Korea) (n=3 with HA grit sandblasted RBM surface; n=3 with a Ca2+ incorporated in titanium XPEED surface and n=3 with machined surface) Ø 8mm x 3mm were used for this investigation. N°1 disk for each surface treatment (tot. n°3 disks) were characterized at time 0 by SEM to study the surface morphology and by AFM to study the surface roughness. The other six disks were mounted on an acrylic bite embedded in a buccal lateral posi- tion (three for each side) worn for 48 hours by a student from Dental School, for biofilm accumulation. After 48 hours each disk was removed and randomly assigned to the control group (to study only plaque accumulation) and to the test group (toinvestigate the effects of the cleaning procedure using tita- nium brushes). All disks were treated by the same operator. The Nickel-Titanium brushes (I.C.T. De Ore, Verona, Italy) were used (one for each disk treated) mounted on a handpiece at 500 rpm speed and 100 N torque for 60 sec time with a calibrated pressure of 25 gr and a continue irrigation of NaCl 0.9%. All disks were then analyzed by SEM at 40x, 500x and 2000x, also in backscattering, and by AFM for the Ra (medium value of roughness) and Rp-v (max peak-max depth value) measurement. All Ni-Ti brushes used were analyzed by SEM and compared to a no used one. RESULTS: The MACHINED surface, after instrumentation, appeared well cleansed. However, the SEM images, revealed considerable surface alterations following treatment. The roughness values increased. The RBM surface showed a mini- mum percentage of residual material and after cleaning had some morphological changes. The typical RBM sandblasted structure appear flattened. The roughness values confirm this change by the reduction in value of R p-v. The cleaning effi- cacy of the brush on the XPEED surface was excellent but the surface morphology changed. The SEM images showed the presence of grooves and flattening caused by the use of brush that have eliminated most of the irregularities and of the peaks, confirmed by the roughness values measured. The EDX spectroscopy provided the evidence that part of the Ca ++ ions coating remains on the surface even after treatment. The statistical analysis shows that the Ra difference was statis- tically significant. (p