In recent years, ceramic implants made of zirconia have secured a niche position next to established titanium implants, due partly to new scientific findings and positive clinical experience with the handling of ceramic implants. The aim of this study was to assess the clinical and radiographic data for monotype ceramic implants that have remained in place for 60 months under masticatory loading.In 2011, this prospective clinical study included patients with a single-tooth gap in the maxilla and mandible. Monotype ceramic implants (Straumann) were used according to a standard protocol. Provisional prostheses were placed after 3 months, followed by final prostheses 3 months later. Patients were invited for a 60-month follow-up. Implant survival was analyzed from lifetime data. Success rates and crestal bone levels were evaluated from implant placement to 6, 12, 36, and 60 months after surgery.From the initial 44 patients recruited, 36 were analyzable for the 60-month follow-up. With one implant lost before the 6-month followup, the survival rate after 60 months was 97.7%, and the mean survival time was 58.7 months. Sixty months after implant placement, the success rate was 97.2% (95% confidence interval = 84.6% to > 99.9%). Mean bone loss after 60 months was 0.99 (± 0.59) mm.After 60 months, monotype ceramic implants made of zirconia achieved success and survival rates comparable with those reported for titanium implants in selected patient populations. Ceramic implants can be used as an alternative to titanium implants at the request of patients and if specifically indicated, for example, due to titanium intolerance.
Abstract Background: Mechanical properties and biocompatibility make zirconia ceramics suitable implant material. The characteristics of tooth‐color like, the ability to be machined and the low plaque affinity make zirconia especially suitable as a dental implant material. The influence of surface modification on the osseointegration of this material has not been extensively investigated. Purpose: Long‐term investigations with titanium implants have shown superior biomechanical results with the sandblasted acid‐etched (SLA) surface, demonstrating a high bone–implant interaction. The objective of this study was to compare two different zirconia surface topographies biomechanically and histologically with the well‐documented titanium SLA surface. Material and methods: Zirconia implants with either a machined (ZrO 2 m) or a sandblasted (rough, ZrO 2 r) surface were manufactured with the exact same cylindrical shape with a standard ITI thread configuration as the SLA titanium implants. The incisors 2 and 3 were removed from both sides of the maxillae of 13 adult miniature pigs and the tissues left to heal for 6 months. After this time period the animals received a total of 78 implants using a randomized scheme, with the titanium SLA implant used as an only individual reference. After healing periods of 4, 8, and 12 weeks 20, 24, and 25 implants, respectively, were subjected to removal torque tests (RTQ) as the main biomechanical analysis of the of the study. A fewer number was resected on bloc, embedded in methylmethacrylat and analyzed for their direct bone apposition under a light microscope. Results: Surface analysis revealed the highest surface roughness for the SLA‐implant, followed by ZrO 2 r and ZrO 2 m. The turned ZrO 2 m implants showed statistically significant lower RTQ values than the other two implants types after 8 and 12 weeks, while the SLA implant showed significantly higher RTQs values than ZrO 2 r surface after 8 weeks. Differences in the bone apposition were observed in the histomorphometric analysis using light microscopy for all surfaces at any time point. Conclusion: The findings suggest that ZrO 2 r implants can achieve a higher stability in bone than ZrO 2 m implants. Roughening the turned zirconia implants enhances bone apposition and has a beneficial effect on the interfacial shear strength.
The purpose of the present study was to investigate the osseointegration of microstructured zirconia implants in comparison with sandblasted and acid-etched (SLA) titanium implants in a biomechanical study.Zirconia implants (4.1 mm in diameter, 10 mm in length) were produced using a new low pressure injection molding technique. After that the implants were acid-etched with hydrofluoric acid. Standard Ti-SLA implants of the exact same shape served as controls. Six months after extraction of incisors 2 and 3, 16 adult pigs received a total of 64 implants in the maxillae. After 4, 8, and 12 weeks the animals were sacrificed, and 59 implants could be analyzed to removal torque (RTQ) testing.The mean RTQ values for zirconia implants were 42.4 Ncm at 4 weeks, 69.6 Ncm at 8 weeks, and 69.3 Ncm at 12 weeks of healing, whereas RTQ values for the Ti-SLA implants were 42.1 Ncm, 75.0 Ncm, and 73.1 Ncm at corresponding time intervals. There is no statistical difference in RTQ values between Ti-SLA and zirconia implants at 8 weeks.Within the limits of the present study it was concluded that acid-etching of zirconia implants enhances bone apposition resulting in RTQ values which were equivalent to that of Ti-SLA.
One hundred temporo-mandibular joints were examined with a super-conducting nuclear resonance tomograph (1.0 Tesla) using various high resolution surface coils. The optimal method proved to be a spin echo sequence with a repetition time of 1,000 msec and an echo period of 28 msec with a 4 mm slice width. There were significant advantages from the non-invasive MRT diagnosis of the temporo-mandibular joints when compared with CT and with arthrography in recognising abnormal discs, changes in the tissues and for post-operative control.
The purpose of this study was to evaluate ceramic dental implants using different esthetic scores. A total of 53 ceramic dental implants were evaluated using the Pink Esthetic Score (PES), White Esthetic Score (WES), and Peri-Implant and Crown Index (PICI). Prosthodontists, orthodontists, oral surgeons, and dentistry students independently performed assessments. The mean value of combined PES + WES was 17.4 points, and the PICI was 523.2 points. Orthodontists assessed a significantly lower result in both indices compared to all other assessor groups (P ≤ .05). Patient satisfaction was very high. The esthetic scores around ceramic implants were considerably higher than the suggested threshold of clinical acceptability.
