The effect of guided flapless implant procedure on heat generation from implant drilling.

The objective of this study was to evaluate the heat generation in vitro during the flapless drilling procedure using surgical drill guides. Ten resin models with bilateral edentulous tooth spaces in the first and second molars in the mandible were used in this study. On one side of the mandible, drilling was performed with a flapless approach using a surgical drill guide. On the other side of the mandible, drilling was performed with a flap approach. The temperature changes were measured during final drilling by thermocouples. The mean maximum temperatures during drilling with guided flapless procedures were 29.5 °C and 32.6 °C at the depths of 3 and 6 mm, respectively, whereas for flap procedures they were 29.4 °C and 31.3 °C. There was no statistically significant difference between the groups. These findings suggest that drilling with external irrigation in an up-and-down pumping motion may not lead to a significant increase the bone temperature during a flapless procedure using surgical drill guides.

Influence of premature exposure of implants on early crestal bone loss: an experimental study in dogs.

OBJECTIVE: Several studies have reported on spontaneous early exposure of submerged implants, suggesting that exposed implants have greater bone loss than nonexposed implants. The purpose of this study was to compare the effects of implant-abutment connections and partial implant exposure on crestal bone loss around submerged implants. STUDY DESIGN: Bilateral, edentulated, flat alveolar ridges were created in the mandible of 6 mongrel dogs. After 3 months of healing, 2 fixtures were placed on each side of the mandible following a commonly accepted 2-stage surgical protocol. The fixtures on each side were randomly assigned to 1 of 2 procedures. In the first, a cover screw was connected to the fixture, and the incised gingiva was partially removed to expose the cover screw (partially exposed group). In the second, a healing abutment was connected to the fixture so that the coronal portion of the abutment remained exposed to the oral cavity (abutment-connected group). After 8 weeks, micro-computed tomography (micro-CT) at the implantation site was performed to measure the bone height in the peri-implant bone. Data were analyzed by Wilcoxon's signed rank test. RESULTS: The average bone height was greater for the abutment-connected fixture (9.8 +/- 0.5 mm) than for the partially exposed fixture (9.3 +/- 0.5 mm; P < .05). CONCLUSION: These results suggest that when implant exposure is detected, the placement of healing abutments may help limit bone loss around the submerged implants.