A custom auricular implant healing abutment: A dental technique.

Skin overgrowth is a complication that hinders bone-anchored prosthetic ear rehabilitation. In order to accurately transfer the healing skin for prosthetic reconstruction, this article introduces a custom-made autopolymerizing acrylic resin auricular cap (button) through indirect pick up of the metal housing. The caps are secured during the healing stage to shape the skin, preventing surgical edema, swelling, and skin overgrowth in patients suffering from keloid reactions from covering the implant abutments. Since skin height and form are changeable, the caps can be relined directly or indirectly if greater skin compression is required. Moreover, these custom-made caps can be utilized during prosthetic silicone ear fabrication to retain the metal housing.

Evaluation of the passive fit and definitive marginal fit of prefabricated and conventional CAD-CAM milled titanium bars with a fully guided surgical protocol: An in vitro study.

STATEMENT OF PROBLEM: Computer-aided design and computer-aided manufacturing (CAD-CAM) milled titanium bars have shown good clinically acceptable passive fit and definitive marginal fit; however, investigations into the passive fit and definitive marginal fit of prefabricated CAD-CAM milled titanium bars are lacking. PURPOSE: The purpose of this in vitro study was to compare and evaluate the passive fit and definitive marginal fit of prefabricated and conventional CAD-CAM milled titanium bars. MATERIAL AND METHODS: A total of 10 polyurethane radiopaque anatomic completely edentulous mandibular models had implants (Biohorizons) placed in the left and right canine and second premolar positions using a 3-dimensionally printed fully guided surgical guide. For the conventional bars, impressions were made, and casts were scanned and exported to a software program (exocad 3.0). For the prefabricated bars, the surgical plans were exported from the software program directly. The Sheffield test was used to evaluate the passive fit of the bars, and marginal fit was evaluated with a scanning electron microscope at ×50 magnification. The Shapiro-Wilk test was used to determine that the data were normally distributed; the data are presented using mean and standard deviation. Group comparisons were made with the independent t test (α=.05). RESULTS: The passive and marginal fit of the conventional bars was better than that of the prefabricated bars. The mean ±standard deviation values for passive fit were 75.2 ±13.7 µm for conventional bars and 94.7 ±16.0 µm for prefabricated bars (P<.001). A statistically significant difference (P<.001) was also found between the marginal fit of the conventional bars 18.7 ±6.1 µm and the prefabricated bars 56.3 ±13.0 µm. CONCLUSIONS: Conventional CAD-CAM milled titanium bars had a better passive and marginal fit than prefabricated CAD-CAM milled titanium bars; however, both had clinically acceptable passive fit ranging from 75.2 to 94.7 µm and definitive marginal fit ranging from 18.7 to 56.3 µm.

Effect of Guiding Sleeve Design on Intraosseous Heat Generation During Implant Site Preparation (In Vitro Study).

PURPOSE: To compare the effect of different designs of guiding sleeves on heat generation during implant surgery while using different cooling fluid temperatures. MATERIAL AND METHODS: Temperature measurements were performed during guided implant site preparation in bovine rib samples using two K- type thermocouples at 2 mm and 8 mm depths. Three groups were tested according to guiding sleeve design: conventional cylindrical sleeve, open C-shaped sleeve, and modified cylindrical sleeve. Each group was irrigated with three fluid temperatures: 10°C, 15°C, and 20°C. The groups were compared using Kruskal Wallis test followed by post hoc comparisons with Bonferroni correction. The level of statistical significance was set at p = 0.05. RESULTS: Surgical guides with conventional cylindrical sleeve design showed significantly higher heat generation during implant site preparation than guides with both the open C-shaped and the modified cylindrical sleeve designs at both 2mm and 8mm depths. The difference between C-shaped and modified cylindrical sleeves was not significant in any group. Using pre-cooled irrigation fluids (10°C and 15°C) reduced the generated heat; however, the differences within the same group were not statistically significant. CONCLUSIONS: The use of a surgical guide with the conventional cylindrical sleeves led to higher heat generation than other sleeve designs, which might reach or near the critical threshold of bone thermal necrosis. Using surgical guides with open sleeves or modified cylindrical sleeves could be helpful in irrigation fluid delivery and decreasing the generated heat.