Predictability and outcome of titanium color after different surface modifications and anodic oxidation.

To investigate the predictability and the outcome of surface modification techniques, including anodization. Four surface modification techniques were evaluated in this in-vitro study: sandblasting (S), polishing+anodizing (PA), sandblasting+anodizing (SA), polishing+etching+ anodizing (PEA). Color coordinates L*, a* and b* were collected using a spectroradiometer. Color differences between all groups were quantified by use of ΔE00. A possible influence of group membership was evaluated using 1-way ANOVA. Pair-wise inter-group comparisons were performed using post-hoc Tukey tests. PA specimens were the brightest and showed a pronounced yellowish and reddish hue. S and SA groups were significantly darker and predictability of outcome was higher compared to another groups. The most predictable surface treatment method is sandblasting. Anodizing techniques come along with the brightest and most chromatic color impression of the titanium.

Color stability of polymer-infiltrated-ceramics compared with lithium disilicate ceramics and composite.

OBJECTIVE: To investigate the color stability of hybrid ceramics and to compare it to composite and lithium disilicate ceramics. MATERIALS AND METHODS: One hundred eighty samples were fabricated and processed with a semiautomatic grinding and polishing device (final step: 1200 grit). After thermocycling, samples were immersed in a staining solution (five subgroups: water, red wine, curry, black tea, cola) for 4 weeks. A spectroradiometer was used to determine the color of the samples in CIE L*a*b*. Color measurements were performed before staining (baseline, initial color), after thermocycling, after 2 and 4 week storage in staining solution and each after a two stage repolishing approach. Discoloration of specimens was calculated by means of ΔE00 compared to baseline values. RESULTS: All factors (material, staining solution, aging stage) were significantly associated with the extent of discolorations (P < .001). Maximum color changes occurred after 28 days staining (EN: ΔE00 = 4.5 ± 4.0; GB: ΔE00 = 5.0 ± 4.5; LS: ΔE00 = 3.0 ± 2.3) clearly exceeding the 50:50 threshold for acceptable color deviations. Due to repolishing, discoloration of LS samples was almost completely eliminated (ΔE00 = 0.4 ± 0.3) and significantly reduced for the other two materials (EN: ΔE00 = 1.0 ± 0.9; GB: ΔE00 = 0.9 ± 0.4; P = .428). CONCLUSION: Discoloration of hybrid ceramics ranged in-between lithium disilicate and composites, however more comparable to composites. Repolishing could reduce discolorations substantially. CLINICAL RELEVANCE: This study should help dental practitioners to estimate the color stability of common dental materials and the effect of polishing in removal of discolorations.

Factors affecting the early failure of implants placed in a dental practice with a specialization in implantology - a retrospective study.

BACKGROUND: To evaluate early failure and possible risk factors for failure of dental implants placed under practice-based conditions. METHODS: To clarify the research question, anonymized data from 106 patients with 186 dental implants were analyzed. The presence of sucessful healing (yes/no) at the time of incorporation of the final prosthesis was assessed. Mixed models were compiled for each target variable to enable estimation of the effects of patient-related and implant-related conditions on the risk of early implant failure. RESULTS: Nine out of 186 implants (4.8%) placed in 106 participants failed before incorporation of the final prosthesis. The use of shorter implants (< 10 mm) and the need for augmentation procedures were associated with a greater risk of early implant failure. For shorter implants, the risk was 5.8 times greater than that for longer implants (p = 0.0230). Use of augmentation procedures increased the risk by a factor of 5.5 (p = 0.0174). CONCLUSIONS: Implants placed in the dental practice with a specialization in implantology heal successfully. The use of augmentation procedures and of implants shorter than 10 mm seems to be associated with a greater risk of early implant failure.

Short-term performance of implant-supported restorations fitted in general dental practice: A retrospective study.

PURPOSE: The objective of this retrospective clinical study was to evaluate the short-term performance of implants and implant-supported dental restorations (single crowns, fixed/removable dental prostheses, and overdentures) and to identify risk factors for prosthetic complications under the conditions of general dental practice. MATERIALS AND METHODS: De-identified data extracted from electronic patient records were analyzed to clarify the research question. Patient-related variables and implant- and suprastructure-related variables were documented for each patient. The probability of complication-free survival after 1 and 2 years was evaluated using the Kaplan-Meier method. In addition, the prosthetic complications were analyzed using Cox regression models. RESULTS: Eighty-four patients with 134 healed dental implants supporting 107 restorations were studied over a clinical period of up to 52 months (mean: 23.9 months). Of the implants placed, nine (4.8%) failed during the healing phase. Of the healed implants, peri-implant bone loss occurred for two implants among two patients. Nonetheless, these two implants remained functional. Complications were as follows: peri-implantitis (1.5%), loss of retention (10%), loosening of the abutment screw (6%), and chipping of the veneer material (3.7%). The probability of complication-free survival for suprastructures alone was 92% (95% CI: 86% to 96%) after 1 year and 84% (95% CI: 75% to 90%) after 2 years of clinical service. Taking into consideration all complications/failures of implants and of restorations, complication-free survival was 86% (80% to 91%) and 79% (70% to 85%) after 1 and 2 years, respectively. CONCLUSION: Both healed dental implants and implant-supported restorations placed in general practice have a high incidence of success; the survival rates seen during the quite short observation period appear comparable to institutional study outcomes. However, technical prosthetic complications are not uncommon among general practice restorations and probably occur more often than in university studies.