Die Bearbeitung von unbeschichteten und Titan-Nitrit beschichteten Titan-Distanzhülsen mit verschiedenen Instrumenten

An in vitro study of the effect of mechanical treatment of pure titanium and titanium nitride-coated abutments This in vitro study on pure titanium and titanium nitride-coated abutments is aimed to examine the traces left by various instruments and to determine the quantity of substance removal. The relevant abutments were test material from 3i-Implant Innovations, USA. The instruments used were titanium curettes, steel curettes, plastic curettes, rubber cup with Zircate Prophy Paste, ultrasonic scaler (Sonicflex) with steel tip and airpolishing system (Prophyflex) with cleaning powder. Two test fields (2mm2 ) on the 11 pure and 11 nitride-coated abutments underwent standard treatment with each instrument. The instruments were used in accordance to the instructions given by the respective manufacturer. Nontreated abutment surfaces served as controls. The treated and nontreated surfaces were examined by a mechanical profilometer (Perthometer S8P Feinprüf GmbH, Göttingen) for an increasing roughness (Rz) and substance removal (Pt). The examinations by the scanning electron microscope and light microscope were to evaluate certain traces caused by the treatment. The results showed that the use of the steel curette left pronounced traces, increased roughness (Ti:+127,4%/TiN+83,2%) and induced high substance removal on both test abutments (Ti:8,48µm +/- 2,81 / TiN4,80µm +/- 0,99). Only the lower pressure of 0,4N left no visible traces and no substance removal on the TiN-coated abutment. The use of the titanium curette showed pronounced traces without a measurable substance removal on all abutments. The pressure of 0,4N had a minor effect on the TiN-coated test field than on the uncoated. An increasing roughness is only visible on the uncoated abutments (+210,2%). The ultrasonic system left pronounced traces on the uncoated test fields including a highly increased roughness (+339,4%) and an enormous substance removal (17,57µm +/- 2,87). The TiN-coated abutments showed little to moderate traces. In this case the treatment had a smoothened effect (-53,1%) without any substance removal. The use of the rubber cup created on the uncoated abutments little to moderate traces without any substance removal, whereas there was a smoothened effect visible on the nitride-coated test fields with a reduced roughness (-66,4%), no substance removal and only little traces on the surface. The plastic curette and the airpolishing system left both abutment surface unchanged. The additional examination by a special light microscope (Zeiss MBO 50, DigitalkameraProgRes 3008) was used to point out damages of the nitride coating in colours after the instrumentation by the ultrasonic scaler, the steel und titanium curette. The ultrasonic system left only little traces but created a visible removal of the TiN-layer. The titanium curette at a pressure of 4N partly removed the coating. The use of the steel curette left pronounced traces with a completely removed coating. In summary, the TiN-coated makes the transgingival portion more resistant against invasive periodontal hygiene treatments like steel curette and ultrasonic but the coating gets lost even after a single treatment and the basic roughness of the untreated control fields of the TiN-coated abutments is much higher than the roughness measured on the untreated pure titanium abutment.