Aug 2026· International Journal of Implant Dentistry· Vol 12· 0 citations· 38 references
Medicine
TL;DR
The 39.1% early failure rate within the first 12 months was followed by stable marginal bone levels through 36 months in implants that achieved successful osseointegration, underlining the need for peri-implant maintenance.
Abstract
To evaluate the 36-month survival and clinical outcomes of two-piece zirconia implants restored with screw-retained glass-ceramic crowns on PEKK abutments. This prospective single-center clinical study evaluated implant survival as the primary outcome, with secondary outcomes including peri-implant soft tissue parameters, marginal bone level changes, and patient-reported outcome measures. Twenty-four patients received single CERALOG Hexalobe two-piece zirconia implants manufactured by ceramic injection molding (CIM) in healed sites. After 6-month submerged healing, implants were restored with provisional screw-retained crowns on PEKK abutments, followed by definitive lithium disilicate crowns (IPS e.max Press) on PEKK abutments secured with titanium abutment screws (25 Ncm). Clinical and radiographic examinations were performed at implant placement, re-entry, definitive loading, and at 12-, 24-, and 36-month follow-ups. Implant survival was analyzed using Kaplan–Meier estimates. Of 23 evaluable implants, nine failed within the first 12 months: six due to failed osseointegration (two at re-entry, three during provisional restoration, one after definitive loading) and three due to implant fracture (one during provisional restoration, two after definitive loading). Kaplan-Meier survival rate was 60.9% (95% CI; 41–81%) at 12 months. No additional failures occurred between 12 and 36 months. Peri-implant soft tissue parameters of surviving implants showed favorable trends (PPD: 2.7 ± 0.7 mm at 12 months, 2.0 ± 0.5 mm at 24 months, 1.9 ± 0.8 mm at 36 months; BOP: 26%, 21%, and 18%, respectively; MGI: 0.38 ± 0.36 at 12 months, 0.40 ± 0.76 at 24 months, 0.21 ± 0.48 at 36 months). At the implant level, peri-implant mucositis was diagnosed in 7 of 13 implants (53.8%) at 36 months; no peri-implantitis was observed throughout the observation period. Mean DIB was 1.9 ± 0.6 mm at definitive loading, 1.6 ± 0.5 mm at 24 months, and 1.5 ± 0.9 mm at 36 months. One abutment screw loosening at 24 months was successfully managed. Patients with surviving implants reported high satisfaction scores (overall satisfaction: 5.0 ± 0.0 at 36 months). The 39.1% early failure rate within the first 12 months was followed by stable marginal bone levels through 36 months in implants that achieved successful osseointegration. However, peri-implant mucositis remained prevalent at 36 months, underlining the need for peri-implant maintenance. The early post-loading period represents the critical determinant of long-term implant survival in this system. Extended follow-up through 60 months is ongoing.
Conventional screw- and cement-retained single implant restorations are associated with biological and technical complications. Friction-retained conometric concepts have been proposed as an alternative; however, clinical evidence for single crowns, particularly from prospective multicenter studies, remains limited. This study evaluated the 1-year clinical performance of a conometric retention system for implant-supported single crowns. This prospective multicenter study was conducted at nine clinical centers in Europe and North America. Subjects requiring single-tooth replacement in the maxilla or mandible received one implant restored with a prefabricated 5.9° conometric abutment and a titanium nitride–coated coping. All-ceramic crowns were extraorally bonded and seated without cement or screws. Radiographs were obtained at implant placement, delivery of the permanent restoration, and after 1 year. Primary outcomes were implant and prosthetic survival. Secondary outcomes included marginal bone level (MBL) changes, bleeding on probing, plaque, probing pocket depth, and complication rates. Descriptive statistics and confidence intervals were calculated. A total of 144 implants were included in the per-protocol analysis. Three implants failed after delivery of the permanent restoration, resulting in a 1-year implant survival rate of 96.7%. Of 131 restorations evaluated at 1 year, 4 showed irreversible loss of conometric retention and were classified as prosthetic failures. In total, 22 prosthetic complication events were recorded, including 18 reversible technical complications (12.5%) and 4 irreversible failures, corresponding to an overall complication rate of 15.3%. Mean MBL change was − 0.11 mm from implant placement to PR and − 0.02 mm from PR to 1 year. Within the limitations of this 1-year analysis, the investigated conometric retention system demonstrated high implant and prosthetic survival rates and limited marginal bone changes. However, a clinically relevant incidence of technical complications, including irreversible loss of conometric retention, was observed during the first year of function. These findings suggest that the conometric concept may require careful case selection and clinical monitoring. Long-term follow-up is required to further evaluate the clinical stability and prosthetic reliability of this retention concept over time. Trial registration: ClinicalTrials.gov, ID, NCT04063878, August 20, 2019.
Peter Gehrke, Octavio Weinhold, Pelayo Antuna et al.· International Journal of Imp...· 0 citations
OBJECTIVE
Evidence on zirconia dental implants remains limited. This retrospective study evaluated clinical and radiographic outcomes of contemporary ceramic implant systems placed in private practice with variable follow-up of up to 11 years.
MATERIALS AND METHODS
This retrospective cohort evaluation included 174 patients receiving 275 zirconia implants (one-piece systems and a two-piece tissue-level screw-retained system) placed between 2013 and 2025 with a minimum one-year follow-up. Implant survival and success rates were assessed. Standardized periapical radiographs were analyzed using ImageJ to measure marginal bone levels at placement and annually thereafter. Peri-implant soft tissue health was evaluated using the modified Plaque Index and modified Gingival Index.
RESULTS
Kaplan-Meier cumulative implant survival was 97.6%, and overall success was 95.3%. Mean first-year marginal bone loss ranged from 0.25 to 0.74 mm, with a pooled mean of 0.49 mm. Mean annual bone loss after year 1 was low at 0.12 mm/year. Soft tissue indices remained low, and no suppuration was observed. Two implant fractures occurred (0.73%); remaining failures were associated with lack of osseointegration or aseptic loosening.
CONCLUSIONS
Within the limitations of this retrospective study, contemporary ceramic implant systems demonstrated high survival and success with stable peri-implant bone levels and favorable soft tissue conditions.
CLINICAL SIGNIFICANCE
This study provides real-world clinical and radiographic data on contemporary ceramic implant systems, including one-piece ceramic implants and ATZ two-piece ceramic implants with carbon fiber screws. These findings may help clinicians contextualize the observed performance of ceramic implants in daily practice. Ceramic implants may represent a viable metal-free treatment option for appropriately selected patients, particularly in esthetically demanding situations, when careful case selection, system-specific training, and adherence to surgical and restorative protocols are applied.
M. Monzavi, Medis Masnavi, Ayman Zraiqat et al.· Journal of Esthetic and Rest...· 0 citations
OBJECTIVES
To compare the clinical, biological, and technical outcomes of posterior three-unit implant-supported fixed dental prostheses (iFDPs) fabricated from monolithic zirconia (MonoZR) or porcelain-fused-to-metal (PFM).
MATERIALS AND METHODS
In this prospective randomized controlled trial, partially edentulous patients requiring a posterior three-unit iFDP supported by two implants were randomly assigned to MonoZR or PFM iFDPs. The primary outcome was ceramic fracture. Secondary outcomes included prosthesis survival, complication-free survival, marginal bone level (MBL) changes, peri-implant clinical parameters, and USPHS ratings. Follow-up examinations were performed at 1 and 3 years. Statistical analyses included Kaplan-Meier estimates, Fisher's exact test, and linear mixed-effects models (α = 0.05).
RESULTS
Fifty-five patients received iFDPs at baseline (MonoZR: n = 28; PFM: n = 27), and 45 completed the 3-year follow-up. Two prosthesis failures occurred, one in each group, both associated with implant loss, with no difference in survival between groups (p = 1.00). Veneering ceramic chipping occurred only in the PFM group (3/23; 13%) and not in the MonoZR group (0/22) (p = 0.11). Complication-free survival, peri-implant clinical parameters, and MBL changes did not differ significantly between groups (p > 0.05). Plaque index and bleeding on probing increased over time, while probing depth and MBL remained stable. Both groups showed high clinical acceptability according to USPHS criteria.
CONCLUSIONS
Both MonoZR and PFM posterior three-unit iFDPs demonstrated high survival and favorable biological outcomes after 3 years. MonoZR showed no chipping events and may represent a promising alternative to PFM for posterior implant-supported restorations.
TRIAL REGISTRATION
German Clinical Trials Register: DRKS00011039.
Aspasia Pachiou, Raphael Singh, Ronald E. Jung et al.· Clinical Oral Implants Resea...· 0 citations
The clinically meaningful esthetic advantages of IIP support its preferential use in the anterior zone when anatomical conditions permit and when combined with guided protocols and customized healing abutments, IIP and EIP yield comparable 12-month marginal bone outcomes.
Sara N. El Touliani, Ahmed M. Abdel-Hamid, Nada M. H. Fahmy et al.· Frontiers in Dental Medicine· 0 citations
PURPOSE
To evaluate the long-term survival, complications and peri-implant marginal bone loss (PIMBL) associated with immediately functionally loaded single implants after 12 years of follow-up.
METHODS
Forty-six patients treated at six clinical centers received single implants placed either in healed ridges or fresh extraction sockets and restored under immediate functional loading. All implants were placed according to a standardized surgical and prosthetic protocol and followed for 12 years. Primary outcome measures included implant survival, biologic and prosthetic complications, and PIMBL.
RESULTS
Fifty-seven implants were placed, including 47 in healed sites and 10 in extraction sockets. Six patients (seven implants) were lost to follow-up. After 12 years, only two implant failures were recorded, resulting in survival rates of 95.7% at the patient level and 96.5% at the implant level. Biologic complications occurred in 4.3% of patients and 3.5% of implants, whereas prosthetic complications affected 15.2% of patients and 12.2% of implants. Mean PIMBL at 12 years was 0.41 ± 0.18 mm, with comparable values observed in healed sites and extraction sockets.
CONCLUSIONS
Immediate functional loading of single implants demonstrated favorable long-term clinical performance, limited biologic and prosthetic complications, and excellent peri-implant bone stability. When adequate primary stability and appropriate case selection are achieved, this treatment approach appears to be a predictable option for single-tooth rehabilitation.
Giuseppe Luongo, C. Lenzi, Fabrizia Luongo et al.· International Journal of Pro...· 0 citations
Immediate implants placed 6 mm below the mid-buccal gingival level showed significantly less short-term marginal bone loss than immediate implants placed 4 mm below the gingiva after a period of 1 year.
Jonas Alkimavicius, Manish Rathi, Ula Linkeviciute et al.· Journal of Prosthodontics· 0 citations
