OBJECTIVES:To establish a novel comprehensive classification system for supracrestal soft tissue height (STH) in posterior edentulous regions. On the basis of cone-beam computed tomography (CBCT) measurements of posterior STH, the distribution proportion of each STH category and its influencing factors were analyzed. Implant protocols were proposed according to class. MATERIALS AND METHODS:CBCT images of 600 posterior edentulous teeth from 410 patients who met the inclusion criteria were included (average number of edentulous sites per patient is 1.46). The STHs of the edentulous areas were measured and divided into three classes: Class I (≤3 mm), Class II (3-4.5 mm), and Class III (≥4.5 mm). The percentage of STHs in each class was determined, and the relationships between the STH and sex, age, jaw, and tooth position were analyzed. RESULTS:Class I accounted for most STHs (75.3%), Class II accounted for 23.5%, and Class III accounted for 7 cases (1.2%). Sex was associated with STH, with thicker STHs (2.63±0.81 mm) in males than in females (2.38±0.77 mm) (p<0.05); the female group had a greater probability of thin STH (79.5%). The STH of the maxillary region (2.70±0.78 mm) was thicker than that of the mandible (2.25±0.73 mm), and the STH of the second molar (2.65±0.87 mm) was thicker than those of the premolar (2.45±0.74 mm) and first molar (2.33±0.73 mm) (p<0.05). Age was not associated with STH. CONCLUSION:Based on our classification, most sites belonged to Class I, followed by Class II, with few Class III cases. Gender, jaw position and tooth site correlated with posterior STH, whereas age did not.
This case report describes a digitally integrated surgical and prosthetic approach for mandibular rehabilitation after ameloblastoma resection. Virtual surgical planning and patient-specific guides were used for segmental resection and immediate reconstruction of an approximately 5- cm continuity defect with a nonvascularized anterior iliac crest corticocancellous graft and a preplanned reconstruction plate. After graft incorporation, prosthetically driven implant planning, guided placement of four implants, and digital fabrication produced a titanium-supported monolithic zirconia prosthesis. At 1 year, function, speech, esthetics, and patient satisfaction were favorable. The case illustrates how digital planning can coordinate established surgical and prosthetic methods, although longer follow-up is required.
PURPOSE:Dental implants are a widely used and effective method for tooth replacement, yet complications such as abutment screw loosening remain a challenge. The aim of this study was to investigate the effect of different abutments, connection types and restoration types on abutment screw loosening. MATERIALS AND METHODS:A retrospective analysis was conducted on 161 patients (85 women, 76 men; mean age 53 ± 6.3 years) with 308 abutments in zirconia-based implant-supported fixed dental prostheses (FDPs). Kaplan-Meier analysis and the log-rank test were used to analyze and compare the screw loosening probabilities and mean estimation time to torque loss after loading of implant supported restorations with different implant systems, abutments and restorations type, and tissue vs bone level implants. The torque value of studied abutments was analyzed by Kruskal-Wallis test and Mann-Whitney Test. One way analysis of variance and independent sample t test were used to compare torque loss value of abutment's type, single vs multiple FDPs, and tissue Vs bone level implants. The level of significance was set at 0.05. RESULTS:The overall survival rate of implant-supported FDPs was 99.2%. Complete loosening occurred in 2.1% of abutments. Torque loss values were significantly different between implant systems (p < 0.001), restoration types (p < 0.001), and tissue-level versus bone-level implants (p < 0.05). Tissue-level implants and multi-unit FDPs demonstrated more removal torque. No significant differences in torque loss were found between angled, straight, and solid abutments (p = 0.19). CONCLUSION:Torque loss and probability of screw loosening of different implant systems were significantly different. Multi-unit FDPs and bone level implants showed significantly less torque loss while abutment type did not influence the screw loosening.
PURPOSE:To evaluate the proximal bone behavior and 1-year survival rate of immediately loaded Ø2.9 mm narrow-diameter implants. MATERIALS AND METHODS:Eighteen immediately loaded implants were retrospectively assessed by standardized radiographic analysis at three time points: T1, immediately after placement; T2, 4-6 months post-loading; and T3, 12 months post-loading. Mesial and distal bone levels were measured relative to the implant-abutment interface at two positions: the point of bone contact with the implant surface (Alt1) and the alveolar crest (Alt2). Statistical significance was set at p < .05. RESULTS:No implant failures occurred, yielding a 100% survival rate. Within the first 6 months, significant bone remodeling was observed mainly at the lateral surface (Alt1), with losses up to 1.47 mm mesially and 1.37 mm distally, particularly in grafted sites (p = .004; p = .016). From 6 to 12 months, bone levels remained relatively stable with minimal additional changes. CONCLUSION:Within the limitations of this retrospective study, immediately loaded Ø2.9 mm narrow-diameter implants demonstrated 100% survival and stable peri-implant bone levels after 12 months. The most pronounced remodeling occurred at the lateral bone surface during the first 6 months, especially in grafted sites, followed by stability, supporting their short-term clinical predictability.
PURPOSE:To investigate the effects of prosthesis and pickup materials on the shear bond strength and failure modes of temporary cylinders in full-arch implant-supported interim prostheses. MATERIALS AND METHODS:A fully edentulous study model with four implants was prepared, and full-arch interim prostheses were fabricated from either 3D-printed nanoceramic hybrid resin or heat-cured acrylic resin (n = 9 per material). Titanium temporary cylinders were connected to the implants, and three pickup materials were applied to secure the cylinders in the prostheses: acrylic resin, modified acrylic resin, and bis-acryl composite resin. After polymerization, cylinders were subjected to a push-out test, and maximum force and shear bond strength were calculated (n = 12 per group). Failure modes were classified as adhesive, cohesive, or mixed. Statistical analyses included Kruskal-Wallis with post hoc Dunn's tests, Mann-Whitney U, and mixed-effects modeling (α = .05). RESULTS:Maximum push-out force and shear bond strength differed significantly among pickup materials (P < .001), with acrylic and modified acrylic resins showing the highest values and bis-acryl composite resin the lowest. 3D-printed prostheses generally exhibited higher bond strength and cylinder retention than did heat-cured prostheses, although push-out differences were not significant. Failure modes were mainly adhesive, with minor cohesive remnants for acrylic and modified acrylic resins, while bis-acryl composite resin showed adhesive failure with material fragmentation. CONCLUSION:Acrylic-based pickup materials provided higher shear bond strength than bis-acryl composite resin, and 3D-printed nanoceramic hybrid resin prostheses offered superior bonding performance compared with heat-cured acrylic resin prostheses.
PURPOSE:To evaluate whether hierarchical nano-in-micro (NIM) architecture combined with biofunctional chemistry enhances early osseointegration compared with a hydrophilic SLActive surface and to characterize interfacial biomechanics using a newly developed continuous removal torque-rotation (RTQ-rotation) analysis system. MATERIALS AND METHODS:Nanoimprinted SLA implants incorporating pit-confined NIM architecture and amine/carboxyl (-NH₂/-COOH) functional groups were compared with SLActive implants in a paired rabbit femoral model after 3 weeks (n = 11). Surface morphology and chemistry were analyzed by SEM/FE-SEM and XPS. The RTQ system continuously recorded torque versus rotation angle to assess interfacial strength and exploratory descriptors of stiffness, toughness, and failure behavior. RESULTS:Conformal NIM architectures (10-80 nm) with biofunctional surface chemistry were imprinted within pre-existing micropits of SLA, SLActive, TiUnite, OsseoSpeed, and TSIII SA surfaces while preserving original microtopography. Nanoimprinted SLA implants demonstrated significantly higher removal torque than SLActive controls (84.1 ± 8.2 Ncm vs 65.1 ± 10.0 Ncm; p = 0.002). RTQ-rotation analysis revealed approximately 75% higher interfacial stiffness (3.96 vs 2.26 Ncm/degree), faster torque engagement (75.6 Ncm at 19.1-degree rotation), and increased resistance to progressive interfacial failure. Qualitative histology demonstrated more continuous early bone formation along nanoimprinted implant surfaces. CONCLUSIONS:Nanoimprinted SLA implants exhibited enhanced early interfacial biomechanics and qualitative bone response compared with SLActive. RTQ-rotation analysis revealed exploratory differences in interface stiffness, toughness, and failure resistance not detected by conventional peak torque measurement alone. Within the limitations of this 3-week rabbit model, these findings suggest that hydrophilic microtopography may not represent the biological limit of early osseointegration and that hierarchical NIM architecture combined with biofunctional chemistry may promote early bone-implant integration.
OBJECTIVE:The distal changes of mandibular second molars (M2M) after the extraction of mandibular third molars (M3M) are manifested as deep periodontal pocket, attachment loss and bone defects. The purpose of this study was to evaluate the influence of concentrated growth factor (CGF) and Bio-Oss bone powder on alveolar bone increment and pink esthetic score (PES) in patients with lower molar defects undergoing implant restoration. METHODS:From January 2022 to June 2025, 168 patients with M2M distal bone defects after M3M extraction were classified into Bio-Oss group (93 cases) and CGF+Bio-Oss group (Bio-Oss bone powder and CGF mixed at a 1:1 ratio, 75 cases) by retrospective method. In all 168 patients the implant was placed in the mandibular molar region simultaneously with M3M extraction and grafting of the M2M distal bone defect at the same surgical visit (immediate implant placement); no delayed placement and no site treated by socket preservation alone were included, so that all 168 patients were evaluable for implant success. The primary clinical outcomes were implant success rate and alveolar bone increment at 6 months after surgery, and the secondary outcomes encompassed vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in gingival crevicular fluid before surgery and at 2 weeks and 3 months after surgery, clinical attachment loss (CAL), periodontal probing depth (PD) and PES at 3 months and 6 months after surgery as well as adverse reactions. RESULTS:At 6 months after surgery, the implant success was achieved in 75 cases (100%) in the CGF+Bio-Oss group and in 89 cases (95.70%) in the Bio-Oss group. One case failed due to infection, and three cases failed due to periodontal inflammation. There was no statistically significant difference in implant success rate between the two groups (P=0.191). Alveolar bone increment was (3.37±0.75) mm in the CGF+Bio-Oss group and (2.60±0.74) mm in the Bio-Oss group, and alveolar bone increment was higher in the CGF+Bio-Oss group (P<0.001). Repeated measures analysis of variance (ANOVA) results revealed that the group x time interaction effects of VEGF and BMP-2 were statistically significant in both groups (F=6.877, 5.649, P=0.010, 0.019), with 95%CI of the between-group difference in estimated marginal means (Bio-Oss group minus CGF+Bio-Oss group, averaged across the three time points) being -3.091 to -1.799 for VEGF and -3.942 to -2.768 for BMP-2 respectively. Furthermore, the CGF+Bio-Oss group exhibited higher VEGF and BMP-2 at 2 weeks and 3 months after surgery (P=0.012, 0.021, 0.020, 0.004). CAL and PD were lower while PES was higher in the CGF+Bio-Oss group at 3 months and 6 months after surgery (all P<0.001). No obvious difference was found in the occurrence of adverse reactions between both groups (P=0.881). CONCLUSIONS:For patients with M2M distal bone defects after M3M extraction, the combined use of CGF and Bio-Oss bone powder was associated with a greater alveolar bone increment and showed better periodontal clinical indicators and pink esthetic scores than Bio-Oss bone powder alone, without an increase in adverse reactions. As this was a retrospective observational study, these findings indicate association rather than a causal effect and require confirmation in prospective controlled trials.
PURPOSE:This study compared the effects of local and systemic calcitriol administration on bone regeneration in a xenograft-based rabbit maxillary sinus augmentation model. MATERIALS AND METHODS:Eighteen New Zealand rabbits were randomly assigned to three groups (n = 6 per group at baseline): control (xenograft only), local calcitriol (xenograft hydrated with 0.1 µg/kg calcitriol per sinus), and systemic calcitriol (single intravenous dose of 0.2 µg/kg). After 10 weeks, histomorphological scoring, RT-qPCR quantification of VEGF and BMP-2, and serum 25(OH)D measurements were performed. RESULTS:Osteoblast activity was significantly higher in the local calcitriol group than in the control group (p = 0.024). Ossification scores showed a numerical trend toward higher values in the local group but did not reach statistical significance (p = 0.061). VEGF and BMP-2 expression were approximately 17.2-fold and 29.3-fold higher in the local group compared with controls (Bonferroni-corrected p < 0.001 for both); the systemic group showed intermediate expression without reaching corrected significance. Serum 25(OH)D levels showed no significant between-group differences at any time point. CONCLUSIONS:Local calcitriol delivery was associated with significantly greater osteoblast activity and VEGF and BMP-2 expression, along with a non-significant trend toward higher ossification scores. Local application via routine graft hydration may represent a practical, low-cost strategy to enhance bone regeneration without systemic exposure, warranting confirmation in larger clinical studies.
PURPOSE:Healthy peri-implant soft tissues are essential for implant longevity. Low-level laser therapy (LLLT) has emerged as a promising additional approach for enhancing wound healing after implant surgery, but evidence remains inconsistent. This study evaluates the clinical, radiographic, and inflammatory effects of LLLT on peri-implant soft tissue healing, pain, inflammatory biomarkers, and marginal bone preservation following implant placement. MATERIALS AND METHODS:This randomized, controlled, single-blinded trial included 272 adults requiring single-tooth implants. Participants were randomized to two equal groups, LLLT (n=136) or control (n=136). The intervention involved daily 810 nm diode laser irradiation for five days post-surgery. Outcomes assessed included pain (VAS), healing clinical indices, oral health-related quality of life (OHIP-14), marginal bone loss (MBL), and peri-implant crevicular fluid biomarkers. Statistical analysis was conducted using SPSS software with mixed-effects models adjusted for baseline imbalances. RESULTS:Among 272 participants, baseline demographics and comorbidities were comparable (all p>0.23 and p≥0.658, respectively). LLLT significantly reduced pain scores across all follow-ups (0.35-1.21 points lower, partial η²=0.783) and improved healing indices, gingival inflammation, and bleeding scores compared to controls. The LLLT group demonstrated persistently lower peri-implant inflammatory markers (TNF-α) and higher angiogenic response (VEGF). Radiographic evaluation revealed less MBL in the LLLT group with 0.07-0.22 mm less than control after day 7. Additionally, patients reported improved oral-health-related quality of life. CONCLUSION:LLLT enhances peri-implant wound healing, reduces pain and inflammation, and preserves marginal bone, suggesting its value as a minimally invasive adjunct to implant therapy.
OBJECTIVE:Successful dental implant placement relies on the proper integration of bone graft material into an area of deficient native bone. Traditional radiographic methods provide only qualitative assessments, making it challenging to accurately determine graft maturation and the appropriate time for successful implant placement. This study investigates the potential of visible near-infrared (VNIR) spectroscopy as a noninvasive, quantitative method for assessing compositional changes that potentially correlate with intraoral bone graft healing in novel tissue models. METHODS:Six tissue models representing progressive stages of bone graft (BG) healing were developed using Straumann Xenograft BG, Jason Collagen Membrane, porcine mandibular bone, blood, and gingiva. Spectra were collected using an ASD LabSpec4 spectrometer with an infrared fiber-optic probe. Preprocessing techniques were utilized to enhance spectral resolution and enable analysis based on absorbances associated with hemoglobin, protein, lipids, and water. Principal component analysis (PCA) was performed to assess compositional variation across healing stages. Machine learning was applied to PCA scores for classification of stages using linear discriminant analysis (LDA) followed by k-nearest neighbors (KNN). RESULTS:VNIR spectroscopy successfully distinguished bone graft from native bone and captured spectral changes associated with models of progressive graft maturation. Notably, C-H-related absorbances increased from early to late model healing stages, with advanced spectral models more closely resembling healthy bone. Classification using LDA discriminant functions as features for the KNN algorithm achieved a 97% accuracy for prediction of the healing stage. CONCLUSION:VNIR spectroscopy shows strong potential as a noninvasive, quantitative tool for monitoring intraoral bone graft healing. By identifying compositional markers such as C-H absorbances related to lipid or protein in intact bone, this approach may help determine optimal implant timing. Coupled with machine learning, this technique can also offer a user-friendly approach for clinicians. Continued pre-clinical validation with histological studies and animal models is needed to support clinical trials with the eventual aim of enhancing treatment planning and patient outcomes.
Transnasal Implants® are long implants installed in the residual crest of the maxilla, tangent to the lateral wall of the nasal cavity, and anchored apically to the conchal crest of the maxilla. This procedure is known as the Vanderlim Technique® and provides high-torque anterior maxillary anchorage (in Zone 1), favoring immediate loading. Despite being used clinically since 2016, no publication until now has addressed the long-term results of this technique. Therefore, this multicenter study aimed to investigate the survival rates of Transnasal Implants®. MATERIALS AND METHODS:This non-interventional study included clinical data obtained from 226 Transnasal Implants placed in 121 patients treated in five different clinical centers around the world, with procedure time ranging from 1 to 8 years. In common, the patients had atrophic maxillae and sought immediate loading rehabilitation. All underwent the Transnasal Implants® protocol and then immediate loading. Survival analyses were applied as proposed by Buser et al. (1997) and Cochran et al. (2002). RESULTS:A total of 226 Transnasal Implants® were placed in 121 patients from five different centers. All patients underwent immediate loading procedures. The length range of the Transnasal Implant® was 15 to 25 mm, with a diameter ranging from 3.0 to 4.5 mm. Insertion torque above 35/Ncm was obtained in 94.6% of the implants. No early or late failures were observed. The implants met the survival criteria in their entirety. In this study, the survival rate of the Transnasal Implants® was 100%. CONCLUSIONS:The use of long Transnasal Implants® - Vanderlim Technique® for anterior support of upper full-arch rehabilitations allows: (1) anchorage in good quality bone, with high insertion torque; (2) better anteroposterior distribution of the implants; (3) reduction of indications for QuadZygoma, a more complex and invasive procedure; (4) long-term maintenance of soft and hard tissues. The Vanderlim Technique® provides an anterior anchorage option for atrophic maxillae that, combined with additional implants for posterior anchorage, allows rehabilitation with immediate load. It is a surgical alternative to QuadZygoma, being less complex, with lower associated risk and a more accessible alternative for patients and professionals.
OBJECTIVES:The study aimed to assess the biologic quotient, defined as the width-to-thickness ratio between Gingival Width (GW) and Mucosal Thickness (MT), in implant-supported restorations using Preformed Anatomic Caps (PAC, test group) versus conventional healing abutments (control group). MATERIALS AND METHODS:Following dental implant placement in the edentulous ridge with partial-thickness flap elevation, each patient underwent a split-mouth treatment from January 2018 to December 2022, consisting of a conventional healing abutment on one side and a preformed anatomic cap on the contralateral side. Optical scans were used to evaluate the stability of the biologic width-to-thickness ratio over time. The three-dimensional data were voxelized and superimposed to measure the GW and MT digitally, and their biologic width-to-thickness ratio (GW/MT) at different time points was calculated. Superimpositions were performed using MatLab (version 7.0.1, The MathWorks, Natick, MA, USA) and measurements were performed with Dentascan software (JD-igital Guide powered by RealGUIDE™ 5.3, Cantù, Italy). Changes from 2 months to 2 years post-surgery were analyzed. The Wilcoxon signed-rank test, with a significance level set at p < 0.01, was used to compare the paired data. Multivariate regression analysis was performed to assess the potential influence of age, sex, implant arch, and implant position on the observed variables. RESULTS:Data from 30 patients (mean age 52.9±7.8 years; 28 premolars and 32 molars) were analyzed. Gingival widths increased significantly in the test group (+0.3±0.3mm, p<0.0001) and decreased in the control group (-1.4±0.3mm, p<0.0001) over 2 years. Mucosal thickness showed small, non-significant increases in both groups. The biologic width-to-thickness ratios remained stable in the test group (1:1.54 to 1:1.48) but changed significantly in controls (1:1.48 to 1:3.06, p<0.0001). Multivariate regression showed that age, sex, implant arch, and implant position did not independently influence changes in GW, MT, or GW/MT ratio. Subgroup and sensitivity analyses confirmed these findings. CONCLUSIONS:From 2 months to 2 years after surgery, the biologic width-to-thickness ratio remained stable in patients rehabilitated with preformed anatomic caps. The biologic width-to-thickness ratio could serve as a reference parameter for clinicians to assess the maintenance, stability, or loss of the natural appearance of the peri-implant mucosa over time.
PURPOSE:This systematic review and meta-analysis aimed to assess the prevalence of soft tissue dehiscence and survival rates of modern customized titanium subperiosteal implants (CSIs). A secondary objective was to determine whether the anatomical site (maxilla vs. mandible) is a significant predictor of these outcomes. MATERIALS AND METHODS:An electronic search was conducted across PubMed, Scopus, and Google Scholar for clinical studies published between January 2010 and April 2026 involving 3D-printed (DMLS) or milled titanium CSIs. Primary outcomes focused on soft tissue dehiscence, while secondary outcomes assessed implant survival. Statistical modeling utilized Kaplan-Meier estimation for time-to-event analysis and Cox Proportional Hazards Regression to evaluate the influence of the surgical site. RESULTS:Fourteen clinical studies involving 368 implants (276 maxillary, 92 mandibular) were included. The overall incidence of soft tissue dehiscence was 28.6%. While the maxilla exhibited a higher numerical incidence of dehiscence compared to the mandible (31.9% vs. 18.5%), the hazard ratio (HR 1.518) did not reach statistical significance (p=0.116). The overall implant survival rate was 87.8%. However, the surgical site was a statistically significant predictor of failure, though this association may partly reflect differences in case severity between anatomical cohorts; maxillary implants demonstrated a 3.8-fold higher hazard of failure compared to mandibular implants (HR 3.843; 95% CI: 1.157-12.723; p=0.028). CONCLUSIONS:Modern titanium CSIs are a viable solution for severe alveolar atrophy, yet they possess a distinct, site-specific risk profile. While the mandible appears more "forgiving" of soft-tissue complications, maxillary dehiscence is significantly more likely to result in total implant loss. Long-term clinical monitoring is essential, as failure hazards exhibit bimodal "step-like" increases at approximately 35 and 70 months postoperatively.
The application of zygomatic implants (ZIs) in functional maxillary reconstruction for patients with hemimaxillectomy defects is limited by the complex anatomy of the zygomatic bone, restricted surgical fields, and long implant trajectories. Robotic technology has the potential to enhance surgical accuracy and overcome limitations. This study presents a clinical digital workflow for robotic ZI placement and immediate restoration in patients with hemimaxillectomy defects. The process included data collection with cone-beam computed tomography (CBCT), intraoral scanning and 3D reconstruction, virtual surgical planning, prefabricated prostheses, robotic-assisted surgery, and postoperative installation of prefabricated prostheses. Eight ZIs were successfully placed in three four patients with maxillary defects using robotic surgery. No biological or mechanical complications were observed during the 2- to 15-month follow-up period. The mean entry deviation of ZIs was 1.97 ± 1.15 mm, the mean exit deviation was 1.79 ± 1.04 mm, and the mean angular deviation was 1.92 ± 0.76°. The Oral Health Impact Profile-14 questionnaire showed significant improvement in scores postoperatively. This study demonstrates the feasibility and effectiveness of robotic ZI placement in reconstructing maxillary defects, offering a clinical treatment option.
PURPOSE:Implant-abutment complexes from the same brand have evolved with time, retaining similar design features while improving on other aspects. This study investigated the rotational load fatigue performance of narrow, regular, and wide diameter implants with cylindrical and conical internal cam-groove configurations. MATERIALS AND METHODS:Narrow (3.3mm), regular (4.3mm), wide (5.0mm) diameter cylindrical internal cam-groove implants (CAM); and narrow (3.3mm), regular (4.3mm), wide (5.0mm) diameter conical internal cam-groove implants (CNL) were tested with their corresponding universal abutments. The 6 test groups: CAM33, CAM43, CAM50, CNL33, CNL43, CNL50; had five specimens in each group (n=5). A rotational load fatigue machine subjected the implant-abutment test assemblies to sinusoidally varying loads at an angle of 45°, producing an effective bending moment of 35Ncm, at a frequency of 12 Hz, at room temperature of 20°C. The number of cycles to failure was recorded, with the upper limit set at 5 x 106 cycles. Results were evaluated using ANOVA and failed samples were analyzed under SEM to investigate fracture patterns indicative of the mode of failure. RESULTS:5 out of 30 samples, all from the CAM33 group failed. The locations of failure varied across the length of the abutments but the site of fractures on the implants were generally located below the anti-rotational features of the implants. Damage to the abutment, abutment screw and implants were seen in four samples, while one sample had abutment and implant fracture only. All regular and wide diameter implants, and the narrow diameter Conelog implants reached the upper limit without failure. The rotational load fatigue performance of CAM33 was significantly poorer than all the other five tests groups (P = <.001). CONCLUSIONS:CAM33 performed significantly poorer than the other diameters and internal connection. Failures seen in the CAM33 group occurred below the simulated bone level, and these will present a significant clinical challenge to retrieve and replace should any components fail in service.
PURPOSE:The aim of this retrospective study was to evaluate the long-term clinical outcomes of implant-supported prostheses and to analyze the type, frequency, and distribution of prosthetic complications in relation to prosthesis-related factors. MATERIALS AND METHODS:Clinical records of patients who received implant-supported prosthetic treatment between 2017 and 2024 at the Department of Prosthodontics, Faculty of Dentistry, Gazi University, were retrospectively reviewed. A total of 269 patients with 778 implants were included. The follow-up period ranged from 14 to 228 months after functional loading, with a mean follow-up duration of 54.6 months. Fixed, hybrid, and implant-supported overdentures were evaluated. Prostheses were classified according to prosthesis type, restorative material, retention type, and impression level. Prosthetic complications were recorded. Statistical analyses included chi-square tests to evaluate complication distributions and Cox proportional hazards regression analysis to identify factors associated with time to first prosthetic complication. Statistical significance was set at P < 0.05. RESULTS:Implant-supported prostheses showed favorable long-term clinical outcomes; however, biological, mechanical, and technical complications were observed. The most common complications were screw loosening, prosthetic fractures and chipping of the veneering material. Complication rates differed significantly according to restorative material, prosthesis type, retention type, and impression level. Fixed partial dentures showed higher rates of chipping and screw-related complications compared with implant-supported single crowns. Hybrid prostheses, particularly acrylic-based prostheses, showed a higher incidence of acrylic tooth fractures. Cement-retained prostheses were more frequently associated with peri-implantitis, whereas screw-retained prostheses showed higher rates of mechanical complications. Cox regression analysis demonstrated that prosthesis type, restorative material, impression level, and retention type significantly influenced the risk of prosthetic complications (P < 0.05). CONCLUSIONS:Implant-supported prostheses exhibited high long-term survival in the present study; nevertheless, prosthetic complications were observed throughout the follow-up period. Prosthesis type, restorative material, retention type, and impression level were significantly associated with prosthetic complications. Appropriate treatment planning, material selection, regular follow-up, and patient compliance are essential to improve long-term clinical outcomes.
INTRODUCTION AND AIMS:This multicenter randomized controlled trial compared the clinical effectiveness of 7.0-mm wide-diameter implants with 5.0-mm conventional-diameter implants placed immediately after molar extraction. METHODS:Thirty-nine patients needing a single immediate post-extraction implant in a molar site were recruited at five centers. Patients were randomly assigned to receive either a 7.0-mm implant (n = 19) or a 5.0-mm implant (n = 20). Any gaps between bone and implant were grafted with a bone substitute. Definitive zirconia crowns were delivered 4 months after implant placement. Outcomes were assessed 1 year after loading and included implant failures, complications, patient satisfaction, changes in peri-implant marginal bone level (MBL), and pink esthetic score (PES). RESULTS:No patient dropped out. No implant failed in the 7-mm group, whereas one implant failed in the 5-mm group (difference = 5.0%; 95% CI: -4.6% to 14.6%; P = 1.000). Four complications occurred in four patients in the 7-mm group versus zero in the 5-mm group, with the difference being statistically significant (difference = 21.1%; 95% CI: 2.7% to 39.4%; P = 0.047). At loading, mean PES was 5.84 ± 2.34 in the 7-mm group and 6.06 ± 4.04 in the 5-mm group, with no significant difference between groups (mean difference = 0.21; 95% CI: -2.03 to 2.45; P = 0.847). At 1 year, the mean PES score was 9.16 ± 2.22 in the 7-mm group and 9.21 ± 2.88 in the 5-mm group (mean difference = 0.05; 95% CI: -1.64 to 1.75; P = 0.950). Mean peri-implant marginal bone loss was 0.83 ± 1.56 mm and 0.45 ± 1.19 mm, respectively (mean difference = 0.39 mm; 95% CI: -0.53 to 1.30; P = 0.396). CONCLUSION:Preliminary 1-year data showed similar implant survival, esthetic outcomes, and marginal bone loss between 7-mm and 5-mm diameter implants. However, a higher number of minor complications was observed in the 7-mm group. Given the small sample size, larger randomized clinical trials are needed to confirm these findings.
Purpose: To compare the pen-implant bone surrounding a new abutment-free tissue-level implant design with classic tissue-level implants restored with titanium-base (Ti-base) abutments. Materials and Methods: A retrospective cohort study was conducted between 2018 and 2022 in patients requiring dental implants. A total of 53 patients received either a novel abutment-free tissue-level implant (n(1) = 50 sites) or a conventional tissue-level implant (n(2) = 50 sites). Patients were monitored for 1 year after prosthetic loading, with the primary endpoint being any change in hard tissue around the implant. Bone resorption was evaluated using CBCT. Statistical analyses included Fisher exact test for categorical variables and Student t test for continuous variables. Longitudinal outcomes were assessed using linear mixed models to account for within-patient correlations over time. The models incorporated treatment group, time, and their interaction, with statistical significance evaluated using Wald tests. Non-inferiority was assessed with one-sided P values < .025, while two-sided P values <.05 indicated statistical significance. Results:No significant differences in patient demographics or complications were found between abutment-free and conventional implants. However, abutment-free implants exhibited less buccal bone loss than traditional implants. The abutment-free implant group had significantly lower palatal/lingual bone loss (P = .041) and alveolar ridge width reduction (P = .040) after 1 year of follow-up. Conclusions: The results of this study suggest that abutment-free dental implants offer advantages in reducing buccal bone loss compared to conventional implants, potentially due to their ability to mitigate risks to pen-implant tissues. Further research is warranted to evaluate their long-term efficacy and safety.
