Abstract Background Data on market-available two-piece zirconia (ZrO₂) dental implants are limited. Therefore, the aim of this retrospective study was to evaluate the clinical performance of a commercially available ZrO₂ implant system over a 24-month period. Materials and methods In a single private dental office, 35 patients received 63 two-piece ZrO₂ implants for the support of single crowns (SC), fixed dental prostheses (FDP), and overdentures between September 2017 and October 2021. To ensure cohort homogeneity, 31 patients, which received 44 implants to support SCs, were selected for statistical analysis. An anonymized database was used to examine survival and complication rates, marginal bone loss (MBL), and soft tissue parameters. Patients were followed within a defined recall period of at least two years. Descriptive statistics (95% CI) were calculated for MBL, with paired t-tests and one-way ANOVA for comparisons. Associations and clinical parameters were analyzed using Chi-square/Fisher’s exact, paired t-test, and Wilcoxon tests ( p ≤ 0.05). Results During the observation period, no implant losses or implant fractures occurred. The mean MBL was 0.24 ± 0.58 mm at 6 months, 0.18 ± 0.62 mm at 12 months, and 0.20 ± 0.66 mm at 24 months. These values were statistically within the range of random variation. MBL differed between the maxilla and mandible, but not significantly. Probing depths increased significantly over time but did not exceed 2.78 ± 0.26 mm. Bleeding on probing mean values showed a continuous decrease from 9.1 ± 13.7% at baseline to 1.1 ± 4.3% after 24 months, with significant differences between baseline and 24 months, as well from 6 to 24 months ( p = 0.002 and p = 0.003 respectively). Conclusion Over 24 months, two-piece ZrO₂ implants exhibited a 100% survival rate with no observed fractures. MBL was reduced, especially in augmented sites. The presented data support the short-term suitability of this implant system for single-unit restorations. Clinical trial number Not applicable.
Abstract Purpose This study focuses on the characterization and evaluation of innovative surface modifications of zirconia implants aimed at optimizing hard and soft tissue management. Methods The cytocompatibility of newly developed ceramic implant coatings was assessed. Five different surface types were investigated: uncoated zirconia (Zr), zirconia coated with pure titanium (ZrTi), zirconia coated with calcium phosphate (CaP), zirconia coated with hydroxyapatite (HA) and zirconia coated with calcium phosphate-hydroxyapatite (CaP/HA). Cytocompatibility was assessed using L929 mouse fibroblasts and MC3T3 pre-osteoblasts. Testing was performed in both direct and indirect cell contact with the materials. In the direct contact setup, cells were cultured for 24 h on the test surfaces, followed by live/dead staining and fluorescence microscopy. In the indirect setup, material extracts were prepared and cell viability was quantified after 72 h using lactate dehydrogenase (LDH) and cell proliferation (XTT) assays. Results All tested surfaces demonstrated good cytocompatibility without significant cytotoxic effects. Supplementary scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses confirmed the successful application of the coatings and provided detailed insight into surface topography and elemental composition. Conclusion Calcium phosphate and hydroxyapatite-coated zirconia implants represent a promising biocompatible alternative to titanium-based surfaces, with the potential to improve tissue integration and long-term clinical outcomes in ceramic dental implantology.
Horizontal ridge deficiencies in the anterior maxilla frequently compromise ideal implant positioning and esthetic outcomes. This randomized controlled clinical trial evaluated the clinical performance of customized CAD/CAM zirconia membranes compared with conventional collagen membranes for guided bone regeneration (GBR) performed simultaneously with early implant placement. Twenty systemically healthy patients requiring single-tooth replacement in the anterior maxilla underwent early implant placement (4–8 weeks after tooth extraction) combined with simultaneous contour augmentation using a composite graft of autogenous bone and deproteinized bovine bone mineral (1:1). Participants were randomly assigned to receive either a customized CAD/CAM zirconia membrane (test group, n = 10) or a double-layer collagen membrane (control group, n = 10). The primary outcome was horizontal bone gain (HBG) at 6 months, assessed by standardized CBCT superimposition. Secondary outcomes included soft tissue healing evaluated using the Modified Wound Healing Index (MWHI), membrane exposure (wound dehiscence), and patient-reported postoperative pain assessed using a visual analogue scale (VAS). All implants survived during the 6-month follow-up period (100
Abstract Purpose To evaluate the reliability and accuracy of optimized dental-MRI (dMRI) for detecting and classifying peri-implant bone defects around single titanium implants. Methods 48 titanium implants were inserted into bovine ribs. 24 implants had surrounding standardized defects (1-wall, 2-wall, 3-wall, 4-wall) in two sizes (1 mm and 3 mm), while the other 24 implants showed no peri-implant bone defects. CBCT and dMRI were performed and analyzed twice by two readers. 3 Tesla MRI was conducted using an innovative intraoral coil and a novel, T1-weighted sequence for metal artifact reduction (CS-SEMAC). Cohen's Kappa (κ), sensitivity, and specificity were assessed for bone defect detection, size, and type. Modality differences were evaluated using the exact McNemar test and Firth penalized-likelihood logistic regression. Results For bone defect detection, almost perfect intra-/inter-rater reliability ( κ- value range: 0.958–1) was found for both imaging modalities, with high sensitivity/specificity (CBCT 100%/100%, 95% CI 0.962–1.000/0.962–1.000; MRI 98%/100%, 95% CI 0.927–0.998/0.962–1.000), confirmed by Firth regression ( p = 0.22). For defect type classification, both CBCT ( κ- value range: 0.884–0.913) and MRI ( κ -value range: 0.794–0.942) demonstrated almost perfect intra-/inter-rater reliability. Overall sensitivity/ specificity were 86%/99% (95% CI 0.780–0.926 and 0.985–0.995) for CBCT and 84%/99% (95% CI 0.755–0.910 and 0.985–0.995) for dMRI, with no significant difference between modalities (Firth-adjusted OR 0.85, 95% CI 0.38–1.88, p = 0.68). Conclusions Under optimized ex vivo conditions, dMRI offers a promising reliability and accuracy for identifying and classifying peri-implant bone defects around single titanium implants. High-resolution dMRI facilitates radiation-free, three-dimensional peri-implant tissue visualization.
