The effect of heat to remove cement on implant titanium abutment and screw / 대한치과보철학회지

PURPOSE: The purpose of this study was to investigate the effect of heat applied to disintegrate cement on the removal torque value and fracture strength of titanium abutment and abutment screw. MATERIALS AND METHODS: Implants, titanium abutments and abutment screws were prepared for each 20 piece. Implant abutments and screws were classified as the control group in which no heat was applied and the experimental group was heated in a vacuum furnace to 450℃ for 8 minutes and cooled in air. The abutments and screws were connected to the implants with 30 Ncm tightening torque at interval 10 minutes and the removal torque value was measured 15 minutes later. And the fracture strength of abutment screw was measured using universal testing machine. RESULTS: The mean removal torque value was 27.84 ± 1.07 Ncm in the control group and 26.55 ± 1.56 Ncm in the experimental group and showed statistically significant difference (P .05). CONCLUSION: The heat applied for cement disintegration significantly reduced the removal torque value of the abutment screw and did not significantly affect fracture strength of the abutment screw. Therefore, in the case of applying heat to disintegrate cement it is necessary to separate the abutment screw or pay attention to the reuse of the heated screw. However further studies are needed to evaluate the clinical reuse of the heated screw.

Three-year follow-up of full mouth rehabilitation with anterior implant surveyed bridges and distal extension removable partial denture / 대한치과보철학회지

In partial edentulous patients, implant-assisted removable partial denture which provide additional retention and support by placing a small number of implants in strategic positions might be suitable treatment. This case of patient with loss of maxillary posterior teeth and moderate to severe wear of residual dentition, three implants were placed in the maxillary anterior edentulous area and then surveyed bridges were made including remaining anterior natural teeth. Posterior edentulous area was restored with distal extension removable partial denture (RPD). In addition, the worn mandibular natural teeth were restored with fixed prostheses. As a result, reduced vertical dimension and collapsed occlusal plane were rehabilitated, and improved functionally and aesthetically. The purpose of this case was to report the results of three-year follow-up of full mouth rehabilitation with anterior implant surveyed bridges and distal extension RPD.