Jul 2026· International Journal of Implant Dentistry· 0 citations
Medicine
TL;DR
Immediate full-arch rehabilitation combining ZIs and CIs achieved high long-term survival; however, palatal platform positioning and systemic disease were associated with ZI failure.
Abstract
Purpose
Zygomatic implants (ZIs) are indicated for severely atrophic maxillae where conventional implant (CI) placement is difficult. Although ZIs show favourable outcomes, factors influencing their survival remain unclear. This retrospective study evaluated implant- and patient-related factors associated with ZI survival in full-arch immediate-loading rehabilitation using the all-on-four concept combining ZIs and CIs.
Methods
A total of 923 implants (323 ZIs and 600 CIs) placed in 203 patients between 2010 and 2021 were analysed. Cumulative survival rates were estimated using the Kaplan-Meier method, and intergroup comparisons were performed using the log-rank test. Cox proportional hazards regression analyses were performed to calculate hazard ratios (HRs). Statistical significance was set at p < 0.05.
Results
Cumulative survival rates at 3-13 years were 94.5% and 95.9% at the patient and implant levels, respectively, for ZIs, and 97.9% and 98.7%, respectively, for CIs. ZIs showed significantly lower implant-level survival than CIs (p = 0.0178). Palatal positioning of the ZI platform was significantly associated with reduced implant-level survival (HR = 18.177, 95% CI: 1.418-233.053, p = 0.026). Systemic disease was significantly associated with reduced patient-level ZI survival after adjustment for sex and smoking status (HR = 14.872, 95% CI: 1.812-122.077, p = 0.012).
Conclusions
Immediate full-arch rehabilitation combining ZIs and CIs achieved high long-term survival; however, palatal platform positioning and systemic disease were associated with ZI failure.
Rehabilitation of the severely atrophic maxillae remains one of the most demanding challenges in implant dentistry. Zygomatic implants provide a graftless alternative that reduces morbidity and treatment time. However, long-term data exceeding a decade and including patient-reported outcomes remain limited. A retrospective cohort study was conducted on patients who received zygomatic implants from the year 2007 to 2024 at Rajan Dental Institute, Chennai, India. Data collected from digital archives were evaluated to calculate the cumulative survival rates of zygomatic implants. Patient-reported outcome measures (PROMs) on comfort, speech, esthetics, self-confidence, and overall satisfaction were assessed using a Likert-scale questionnaire. A total of 449 patients were rehabilitated with 945 zygomatic implants. Of these, 382 patients rehabilitated with 801 zygomatic implants were included in the study who met the inclusion criteria. The mean follow-up was 8.6 ± 4.1 years. Twenty implants failed in 14 patients, yielding a cumulative implant survival of 97.5% and patient-based survival of 96.3%. Statistical analysis demonstrated sustained survival beyond 15 years, with rates of 97.9% (4 years), 97% (8 years), 91.2% (12 years), and 81.7% (>15 years). PROMs indicated high satisfaction: >90% of respondents reported maximal improvement across all domains. This single-center analysis, with survival rates exceeding 97% over 17 years and excellent patient-reported outcomes, suggests that zygomatic implants provide a predictable and durable solution for severely resorbed maxillae. The integration of PROMs and survival modeling highlights the importance of both biological and psychosocial parameters in defining long-term success.
G. Rajan, K. Srinivasan, M. Saravanakumar et al.· International Journal of Ora...· 0 citations
BACKGROUND
This study aimed to determine the independent influence of bone quality and prosthetic material on medium-term implant survival, peri-implant complications, prosthetic complications, and patient-reported outcomes following All-on-4 rehabilitation.
METHODS
This retrospective, observational, multicenter cohort study included 250 edentulous patients (125 maxillary and 125 mandibular cases) who received All-on-4 implant-supported full-arch prostheses between September 2018 and September 2021. Patients were categorized by bone type (Types 1-4) according to the Lekholm and Zarb classification. Clinical parameters, insertion torque, implant stability quotient (ISQ), peri-implant and prosthetic complications, and patient satisfaction (VAS score) were recorded and analyzed. Prosthetic materials used were either metal-acrylic or monolithic zirconia prostheses.
RESULTS
A total of 1,000 implants were evaluated over a mean follow-up period of 3.6 ± 0.4 years. The overall implant survival rate was 94.8%, with significantly lower survival in Type 4 bone (89.1%) compared to Type 1 (98.3%) (p < 0.05). Peri-implant complications, particularly peri-implantitis and screw loosening, were significantly more frequent in lower-density bone types. Prosthetic complications were analyzed at the prosthesis level and were more frequent in the metal-acrylic group (26.9%) than in the zirconia group (8.9%) (p < 0.001). Despite these differences, patient satisfaction scores were high across all bone types (Mean VAS: 8.7 ± 1.2).
CONCLUSIONS
The All-on-4 concept demonstrated predictable medium-term clinical outcomes, with high implant survival and favorable patient satisfaction in completely edentulous patients. However, poorer bone quality, particularly Type 4 bone, was independently associated with lower implant survival, reduced primary stability, and a higher frequency of peri-implant complications. In addition, monolithic zirconia prostheses were associated with fewer mechanical complications than metal-acrylic prostheses. These findings highlight the importance of individualized treatment planning that integrates bone quality assessment and prosthetic material selection to optimize medium-term clinical outcomes. Although the findings should be interpreted in light of the retrospective observational design and medium-term follow-up, they provide clinically relevant evidence to support risk-informed clinical decision-making in full-arch implant rehabilitation.
Başak Topdağı, Muhammet Kurum, Ceren Cakar Guler et al.· BMC Oral Health· 0 citations
Within the limitations of this study, dental implants placed after interpositional sandwich grafting showed higher long-term survival and less MBL than implants placed after onlay grafting in the atrophic mandible.
M. Dalband, S. Seyfi, H. Behnia et al.· International Journal of Ora...· 0 citations
PURPOSE
To compare long-term outcomes, complications, patient-reported outcomes, and costs of tooth preservation (endodontic treatment followed by long-term prosthodontic restoration) versus extraction with implant replacement at the endodontic-prosthodontic interface.
MATERIALS AND METHODS
A retrospective dual-center private-practice cohort of adults treated with a SAVE pathway or an IMPLANT pathway was evaluated over a 10-year study period with follow-up from 1.0 to 9.6 years after the index unit entered function. Time-to-failure, complications, patient-reported outcomes, and costs were analyzed using Kaplan-Meier/log-rank methods and Cox proportional hazards regression. A propensity-score inverse probability of treatment weighting (IPTW) sensitivity analysis was performed to address confounding by indication and the numerical imbalance between treatment pathways.
RESULTS
The adjusted analytic cohort comprised 859 cases with complete baseline covariates (594 SAVE; 265 IMPLANT); 860 cases were eligible for survival follow-up. Median follow-up was 3.1 years interquartile range (IQR 1.8-4.7; range 1.0-9.6). Failure occurred in 51 cases (37 SAVE; 14 IMPLANT). Estimated survival at 1 year was 97.8% for SAVE and 98.5% for IMPLANT, and estimated survival at the end of the observed follow-up window was 93.8% and 94.7%, respectively. There was no evidence of a survival difference between pathways (log-rank p = 0.785). Implant replacement was not associated with a lower adjusted hazard of failure (hazard ratio [HR] 0.87; 95% confidence interval (CI) 0.47-1.62; p = 0.666), whereas current tobacco use increased failure risk (HR 2.01; 95% CI 1.05-3.86; p = 0.036). Patient-reported oral health-related quality of life (OHRQoL) and satisfaction were comparable. IMPLANT involved more visits, greater downtime, and higher initial, total observed, and cost-per-year-of-function expenses (all p < 0.001).
CONCLUSION
In this private-practice cohort, appropriately indicated tooth preservation and implant replacement demonstrated comparable survival and patient-reported outcomes within the observed follow-up period. The two options should not be treated as interchangeable substitutes; rather, selection should be individualized according to restorability, ferrule feasibility, periodontal and occlusal risk, strategic value, patient preference, maintenance burden, and cost trajectory.
Sagar J. Abichandani, Aneendita Dutta· Journal of Prosthodontics· 0 citations
This retrospective cohort study aimed to explore the relationships between patient characteristics and surgical techniques and radiographic marginal bone loss (MBL) and postoperative complications in individuals receiving dental implants. Electronic medical records (EMR) of adults (age ≥ 18 years) who received at least one dental implant between January 2015 and October 2023 and underwent radiographic evaluation at least 6 months after prosthesis insertion were reviewed. Patient-level variables included demographic, systemic, behavioral, and oral-hygiene characteristics, whereas implant-level variables included implant type, location, and grafting status. Analyses were primarily conducted at the implant level. The oral-hygiene status was retrospectively categorized based on EMR data. MBL was recorded dichotomously based on radiographic evidence of implant thread exposure. Descriptive statistics and exploratory bivariate analyses were performed using chi-square and Fisher’s exact tests, respectively. This study included 218 implants from 109 patients. Most implants were bone-level and placed in the native bone. Grafting was more frequently performed at caries-related sites and in patients with good oral hygiene. Older age was associated with poorer oral hygiene, whereas the education level and smoking status were not significantly associated with the oral-hygiene status. Radiographic MBL and postoperative complications were infrequent. Grafting status was not significantly associated with radiographic MBL. Within the limitations of this retrospective cohort study, good oral hygiene and surgical techniques were associated with favorable short-to-mid-term outcomes of implant treatment. Prospective studies with standardized follow-ups and calibrated radiographic assessments are required to clarify these relationships.
Mohammed Alsarhan, A. I. Alhilal, Abdulmohsen Abdulrahman Alhizam et al.· Saudi Dental Journal· 0 citations