OBJECTIVE:To identify independent risk factors for titanium mesh exposure following 3D-printed individualized titanium mesh (3D-PITM)-assisted alveolar bone augmentation and to evaluate the impact of exposure on bone regeneration outcomes. METHOD:This retrospective study included 52 patients with severe alveolar bone defects who underwent 3D-PITM-assisted guided bone regeneration (GBR) between January 2019 and August 2025, comprising 25 patients with mesh exposure and 27 without. Demographic characteristics and surgery-related variables were collected; univariate analysis and multivariate logistic regression were performed to identify independent risk factors. Additionally, this study measured bone volume, bone height, and bone width at different time points to evaluate the impact of 3D-PITM exposure on bone augmentation. RESULTS:The results showed that smoking, thin gingival biotype, and maxillary defects were significantly associated with mesh exposure (p < 0.05): smoking (OR = 5.16, 95% CI: 1.28-20.82, p = 0.021), thin gingival biotype (OR = 4.21, 95% CI: 1.05-16.82, p = 0.042), and maxillary defects (OR = 11.49, 95% CI: 1.25-105.68, p = 0.031). Regarding bone augmentation, the exposure group showed significantly greater resorption in bone volume (p = 0.0063), height (p < 0.0001), and width (p < 0.0001) than the nonexposure group. Moreover, early exposure resulted in more severe bone loss than late exposure across bone volume (p = 0.0048), height (p = 0.0019), and width (p < 0.0001). CONCLUSION:This study found that 3D-PITM exposure significantly impairs bone regeneration, with smoking, thin gingival biotype, and maxillary defects identified as independent risk factors. Preoperative identification of these risk factors may help reduce mesh exposure and improve bone augmentation outcomes.
OBJECTIVES:To assess 3-year interim results of implant-supported monolithic zirconia single crowns on standardized titanium base vs. customized titanium abutments. MATERIAL AND METHODS:Patients in need of posterior implant were recruited. After implant healing time, patients were randomly allocated to: Ti-Base (n = 30) with a monolithic zirconia crown on a standardized Ti-Base abutment or Custom (n = 30) with a monolithic zirconia crown on a customized titanium abutment. Implant crowns were evaluated at Baseline (BL), 1-year (1Y-FU), and 3 years (3Y-FU) follow-ups for marginal bone level changes (MBL), survival, biological and technical outcomes, and PROMs. Chi-squared and Fisher's exact test were used to assess association between categorical variables, Mann-Whitney's test to compare the distribution of parameters between groups, with a significance level of 5% (α = 0.05). RESULTS:Fifty-one patients (23 Custom, 28 Ti-Base) attended 3Y-FU visit. No implant crowns were lost. Similar median MBL changes from BL to 3Y-FU and comparable biological outcomes were observed in both groups (p > 0.05). No major technical complications were observed, but one minor chipping of Ti-Base zirconia crown was recorded at 3Y-FU, resulting in a technical complication rate of 3.6% for this group. At the 3Y-FU, all patients in the Custom group and 26 patients (92.9%) in the Ti-Base group were very satisfied with the treatment (p > 0.05). CONCLUSIONS:Within the limitations of this interim analysis, monolithic zirconia single crowns on either standardized titanium base or customized titanium abutments demonstrated stable marginal bone levels, high survival rates, high patient satisfaction, and no major technical complications during the 3Y follow-up period. TRIAL REGISTRATION:https://drks.de/search/en/trial/DRKS00012733.
OBJECTIVE:To evaluate the efficacy of mesenchymal stromal cells' (MSC) secretome delivered as conditioned media (CM) as an adjunct to a xenograft (XG) and collagen membrane (MEM) for guided bone regeneration (GBR) in chronic non-contained mandibular defects in minipigs. METHODS:Chronic bilateral mandibular defects were surgically created in seven minipigs. In a split-mouth design, defects were treated with either CM-functionalized (test) or native XG + MEM (control) and evaluated after 4 and 12 weeks. New bone formation was assessed using in vivo computed tomography (CT) and ex vivo micro-CT, histology and immunohistochemistry (IHC). Quantitative CT, micro-CT and histomorphometric data were statistically analysed. RESULTS:No significant differences in new bone formation were observed between the test and control group at either timepoint. These findings could be partly explained by a high intrinsic healing capacity and continual growth of the animals. Minimal residual XG material was detected in both groups at 4 and 12 weeks. When present, these remnants were associated with multinucleated Cathepsin K-positive cells (IHC) with no observable differences between the groups. CONCLUSION:The adjunctive use of MSC secretome in combination with XG and MEM did not improve GBR outcomes in chronic non-contained mandibular defects in the present minipig model. The suitability of this animal model for experimental GBR may be questionable.
AIM:To determine the prevalence and identify risk indicators for peri-implant mucositis (PIM) and peri-implantitis (PI) among implant patients in Malaysian periodontal units. MATERIALS AND METHODS:This multicenter cross-sectional study included 352 patients with 647 implants (mean loading time 6.5 ± 4.0 years) across seven Malaysian states. Clinical evaluation included full-mouth plaque and bleeding scores (FMPS, FMBS), probing depth, tissue phenotype, and prosthetic condition. Peri-implant conditions were classified according to 2017 World Workshop definitions. Generalized Estimating Equation models identified risk indicators. RESULTS:Healthy was observed in 53.7% of patients and 59.7% of implants. PIM affected 36.4% of patients and 31.5% of implants; PI affected 9.9% of patients and 8.8% of implants. Bone-level implants and keratinized tissue width (KTW) < 2 mm were common risk indicators for both conditions. At patient level, FMBS ≥ 10% predicted PI (OR 2.41; 95% CI 1.19-5.05), and ≥ 3 implants were associated with PIM (OR 1.78; 95% CI 1.02-3.11). At implant level, PI was further associated with poor prosthetic condition (OR 4.94; 95% CI 2.38-10.26), splinted crowns (OR 3.48; 95% CI 1.06-11.42), and bridge restorations (OR 3.32; 95% CI 1.31-8.42). No associations were found for age, sex, smoking, or diabetes. CONCLUSIONS:Peri-implantitis affect one in ten implant patients. Due to modest sample size and wide confidence intervals, these findings are exploratory and hypothesis-generating. Potential risk indicators including elevated FMBS, reduced KTW, defective prostheses, and bone-level implants highlight the need for routine assessment of tissue phenotype and prosthetic integrity during maintenance care.
OBJECTIVES:Given the proposed bioactive role of collagen membranes, we aimed to evaluate whether the perforation size of titanium-reinforced dPTFE membranes, with or without an additional collagen membrane, influences outcomes of vertical alveolar ridge augmentation (VARA). MATERIALS AND METHODS:In 12 beagle dogs (24 sites), standardized bilateral chronic mandibular ridge defects (8 × 30 mm) were created and healed for 12 weeks. Sites were randomized (1:1:1) to VARA using porcine xenograft covered with either: (i) non-perforated titanium-reinforced dPTFE (NON-PERF), (ii) perforated titanium-reinforced dPTFE (PERF), or (iii) perforated titanium-reinforced dPTFE covered by a collagen membrane (PERF+CM). After 16 weeks, specimens underwent micro-CT, histology/histomorphometry, vessel quantification, and immunohistochemistry (OCN, ALP, VEGF, TRAP). Continuous outcomes were summarized as medians and compared using the Kruskal-Wallis test with Dunn's post hoc testing when applicable; inflammatory cell scores were analyzed using ordinal logistic regression (α = 0.05). RESULTS:Of 24 treated sites, four had complications and were excluded. All remaining sites achieved around 60% new bone area with no significant intergroup differences (new bone p = 0.5047; soft tissue p = 0.2994; residual graft p = 0.9689). Linear vertical gain was comparable (medians 2.33, 2.87, 2.74 mm; p = 0.7119). Micro-CT outcomes did not differ (e.g., BV/TV, p = 0.2739). Ordinal models did not show significant group differences in inflammatory scores; plasma cell scores in PERF+CM versus control were borderline (OR 15.61; p = 0.0587). CONCLUSIONS:Perforated dPTFE membranes yielded comparable bone gain to unperforated dPTFE. Adding a collagen membrane over perforated dPTFE did not improve VARA outcomes.
OBJECTIVES:To evaluate the effect of different scan body extension designs on the accuracy, usability, and feasibility of digital full-arch implant impressions in an edentulous mandibular model. Accuracy was expressed as trueness and precision, usability as scan time, and feasibility as the number of total scan failures. MATERIAL AND METHODS:An edentulous mandibular model with four implants was fabricated with minimal surface morphology. Five scan body extension configurations were tested: no extensions (control), commercially available extensions, conventional impression copings used as extensions, and two morphological 3D-printed extensions oriented between adjacent implants or toward the center of the arch. Two intraoral scanners were used. For each scanner and configuration, 30 scans were acquired. Inter-implant distances were compared against coordinate measuring machine reference values. Trueness was assessed as mean absolute deviation, precision as standard deviation, and differences were analyzed with non-parametric tests. RESULTS:The highly morphological scan body extensions produced the most consistent improvements. Combined across scanners, trueness improved by 40-57 μm relative to control for the longest inter-implant span. Precision improved significantly for the center-oriented configuration. All scan body extension techniques reduced scan time by 18%-41% and reduced scan failures from 13% (control) to 3% for the morphological designs. Improvements were most pronounced for longer spans and varied between scanners. CONCLUSIONS:Highly morphological 3D-printed scan body extensions significantly improved the accuracy, usability, and feasibility of complete-arch digital implant impressions compared to an unmodified control workflow. Clinical validation is required to confirm these findings for broader use.
AIM:To assess the effect of a hyaluronic acid (HyA) containing gel on patient-related outcomes (PRO) and wound healing after palatal punch-biopsy representing a free gingival graft. MATERIAL AND METHODS:A punch-biopsy (6 mm diameter, 2 mm thickness) was harvested from one side of the palate at Day 0 and from the contralateral side at Day 21. Sites were randomly allocated to either 0.3% HyA containing gel (test) or sterile saline solution (control), professionally applied after harvesting and then self-applied three times/day for 7 days. Up to 21 days PRO-related questionnaires were answered and intraoral scans and photographs recorded to assess wound re-epithelialization, tissue refill, and color match. RESULTS:Eighteen of 25 recruited participants were analyzed. Pain perception, difficulties with eating/drinking, and taste alterations significantly decreased over time and were hardly experienced after Day 7 in both groups (p > 0.05). Participants reported significantly more often a positive experience after applying HyA compared to placebo, that is, in 8 versus 1 out of 18 cases. The residual wound area was significantly smaller in the test compared to control group at Day 7, and cases with a thicker palatal tissue showed tendency for faster re-epithelialization. CONCLUSION:Despite the potential limitations of the present study (i.e., possibility of a carryover effect, questionable blinding of the participants), repeated local application of a 0.3% HyA containing gel appears to only accelerate re-epithelialization in an open palatal wound and provide a positive experience after application, but it did not improve any PRO in such small-sized wounds compared to sterile saline application. TRIAL REGISTRATION:ClinicalTrials.gov identifier: NCT05099718.
OBJECTIVES:To evaluate whether monolithic CAD-CAM lithium disilicate (LS2) crowns are non-inferior to monolithic CAD-CAM zirconia (ZrO2) crowns with respect to clinical and radiographic outcomes in single posterior implant restorations. MATERIALS AND METHODS:Patients with bilateral single-tooth implants at homologous posterior sites were enrolled. Each implant was randomly assigned to receive either a monolithic CAD-CAM ZrO2 crown (Control) or a LS2 crown (Test), both cemented onto customized titanium abutments. Marginal bone level change (ΔMBL) was the primary outcome. Non-inferiority of LS2 relative to ZrO2 was evaluated using a prespecified margin of -0.5 mm for the paired difference in ΔMBL (LS2-ZrO2). Implant and prosthesis survival, biological and technical complications, periodontal parameters, and FIPS were assessed as secondary outcomes. RESULTS:A total of 40 patients completed the 3-year follow-up. The survival rates were 97.5% for ZrO2 and 100% for LS2, with one implant loss in the ZrO2 group. Biological complication rates were 5% for ZrO2 and 15% for LS2 (p = 0.219), while technical complication rates were 2.5% and 5% (p = 1.000), respectively. No crown fractures, chipping, or debonding were found in either group. The ΔMBL was -0.62 ± 1.22 mm for ZrO2 and -0.36 ± 1.07 mm for LS2. The paired mean difference in ΔMBL (LS2-ZrO2) was 0.26 mm (95% CI: -0.17 to 0.70 mm). The lower confidence limit remained above the prespecified non-inferiority margin of -0.5 mm, demonstrating non-inferiority of LS2 with respect to ΔMBL. No statistically significant differences were observed in mSBI, mPLI, or FIPS between the two groups (p = 0.106, 0.201, 0.825). CONCLUSIONS:Monolithic CAD-CAM LS2 crowns exhibit non-inferior clinical and radiographic outcomes to ZrO2 crowns over a 3-year follow-up period. Customized titanium abutments with cemented monolithic all-ceramic crowns represent a reliable treatment option for single posterior implant-supported restorations in the medium term. TRIAL REGISTRATION:Chinese Clinical Trial Registry (chictr.org.cn): ChiCTR2200062023.
AIM:Evaluate the efficacy of adjunctive mechanical/physical decontamination to non-surgical submarginal instrumentation in patients with peri-implantitis. MATERIAL AND METHODS:Patients with at least one implant diagnosed with peri-implantitis were included in this 6-month single-masked randomized clinical trial with three parallel groups: non-surgical submarginal instrumentation with titanium curettes (control); control plus erythritol air-polishing (test 1) and control plus Er:YAG laser (test 2). Clinical variables were collected at baseline, 1, 3 and 6 months. The primary outcome was probing pocket depth (PPD) reduction. Secondary outcomes included bleeding on probing (BoP) reduction and endpoint of therapy (implants with PPD ≤ 5 mm, BoP ≤ 1 site, no suppuration). A multilevel logistic model was computed to evaluate the predictive value of implant- and patient-level variables. RESULTS:Forty-seven patients (84 implants) were enrolled. PPD reductions were observed in all groups (mean: 1-1.4 mm at 1 month), remaining stable at 3 months, with slight relapse at 6 months. All treatments led to significant BoP reduction (24%-36%) at 1 month, with no further significant changes at later follow-ups and no intergroup differences. Therapeutic endpoint rates were 12%-18%. Multilevel analysis suggested an association between the presence of ≥ 2 mm vestibular keratinized mucosa and the use of Er:YAG with higher odds of achieving treatment success. Healing was uneventful in all groups, except for one case of surgical emphysema associated with erythritol air-polishing. CONCLUSION:Irrespective of the adjunctive treatment modality, achievement of peri-implantitis therapeutic endpoint was limited across groups. Possible associations with treatment outcomes were observed; these findings require confirmation in larger studies. TRIAL REGISTRATION:ClinicalTrials.gov identifier: NCT03451981.
OBJECTIVES:The aim of this study was to evaluate the adjunctive effect of electrolytic cleaning in the surgical treatment of peri-implantitis. MATERIALS AND METHODS:A total of 40 patients (44 implants) with peri-implantitis-associated intra-bony defects were included in this single-center randomized controlled trial. Surgical decontamination of implant surfaces was initiated by use of a rotating titanium brush. Following random allocation, adjunctive electrolytic cleaning was performed in the test group. Xenogeneic bone substitute and a resorbable collagen membrane were then used in both groups. Clinical parameters including probing pocket depth (PPD), bleeding/suppuration on probing, buccal mucosal recession (REC), and keratinized mucosa were assessed at 6 and 12 months. Radiographic marginal bone levels (MBL) and patient-reported outcomes (PROs) were evaluated at 12 months. The primary outcome was a composite measure including implant survival, complete absence of BoP/SoP, PPD ≤ 5 mm and REC ≤ 1 mm at 12 months. RESULTS:At 12 months, no implants were lost. The composite outcome was complete at 27.3% of control and 40.0% of test implants (p = 0.41). Mean PPD reductions were 4.5 ± 2.6 mm (control) and 3.8 ± 2.3 mm (test), while MBL gains were 1.9 ± 2.4 mm and 2.1 ± 2.0 mm, respectively. No significant intergroup differences were observed for any clinical, radiographic or PROs. Post-surgical complications occurred in the test group. CONCLUSIONS:Clinical, radiographic and patient-reported outcomes of surgical therapy of peri-implantitis were favorable at 12 months. The adjunctive use of electrolytic cleaning provided no added benefit over the use of a rotating titanium brush alone. TRIAL REGISTRATION:ISRCTN17197337 (ISRCTN).
To assess the 5-year dimensional stability of buccal hard-tissues following guided bone regeneration (GBR) of peri-implant dehiscence defects using deproteinized bovine bone mineral (DBBM) blocks or particulate. METHODS:Patients requiring single-tooth implants and presenting a buccal dehiscence defect (≥ 3 mm) at implant placement were randomly allocated to GBR using either particulate DBBM or an individually shaped DBBM-block, both covered with a resorbable collagen membrane. Buccal hard-tissue thickness was assessed using cone-beam computed tomography postoperatively, at 6 months and at 5 years. Buccal horizontal thickness at the implant shoulder and corono-buccal thickness measured at 45° were recorded. Secondary outcomes included marginal bone levels, clinical parameters and implant survival. Linear mixed-effects models were used to compare the groups to account for within-subject correlations. RESULTS:Twenty-two of 24 patients completed the 5-year follow-up. Buccal hard-tissue thickness decreased over time in both groups, however, the block-group showed significantly greater dimensional stability. At 5 years, mean buccal horizontal hard-tissue thickness was 1.36 ± 1.16 mm in the block-group and 0.07 ± 0.16 mm in the particulate-group (adjusted mean difference, -1.2 mm; 95% CI, -1.9 to-0.6; p < 0.001). Corono-buccal thickness at 45° was also significantly greater in the block-group (adjusted mean difference, -0.3 mm; 95% CI, -0.5 to -0.1; p = 0.002). Marginal bone levels and clinical parameters showed no clinically relevant differences. No implant loss or peri-implantitis was observed. CONCLUSION:GBR using either DBBM blocks or particulate DBBM resulted in similar peri-implant clinical outcomes and implant survival at 5 years. However, DBBM blocks provided superior long-term preservation of the buccal hard-tissue contour. TRIAL REGISTRATION:Clinical Trial Registration Number, DRKS00005803.
OBJECTIVES:This RCT evaluated and compared the clinical performance of zirconia and titanium dental implants placed in the maxillary premolar region. Outcomes were assessed 3 years after prosthetic loading and included marginal bone level (MBL) changes, clinical parameters, aesthetic outcomes, and patient related outcome measures (PROMs). MATERIALS AND METHODS:Fifty patients were randomly allocated to receive either a zirconia one-piece (ZrO2, n = 25) implant or a titanium bone-level (Ti, n = 25) implant, restored with a lithium disilicate crown 3 months after implant placement. Primary outcome was change in MBL. Secondary outcomes included implant survival, peri-implant tissue health, technical complications, aesthetic outcomes, and PROMs. Examinations were performed 3 years after crown placement. RESULTS:After 3 years, mean MBL change was -0.02 mm (SD = 0.78) for ZrO2 and -0.04 mm (SD = 0.36) for Ti; no statistically significant difference was found (p = 0.635). One ZrO2 implant failed to osseointegrate. Clinical parameters were favourable for both implant types, although slightly higher bleeding scores were observed for ZrO2. Differences in aesthetic outcomes and PROMs were found, favoring the ZrO2 implant group. None of these differences reached statistical significance. CONCLUSION AND CLINICAL IMPLICATIONS:After 3 years of function, the ZrO2 and Ti implant as applied in this study showed comparable MBL changes. Survival, clinical and aesthetic parameters, and PROMs were generally favourable and largely comparable for both groups. These short-term findings indicate that both implant types represent a viable option for clinical use in this application. TRIAL REGISTRATION:CCMO registration: NL58957.042.16.
OBJECTIVES:To evaluate the fracture resistance, fracture modes, and crystalline phase changes of zirconia one-piece implants (OPI) and bone-level (BLTPI) or tissue-level, two-piece implants (TLTPI), with ceramic (C) or titanium (T) abutment screws after dynamic preloading in a moist environment. MATERIALS AND METHODS:Dynamic preloading under moist conditions and subsequent static load-to-fracture testing were performed to evaluate fracture resistance and fracture mode. Scanning electron microscopy (SEM) analysis of fracture surfaces was employed to supplement the observations of macroscopic fracture modes. Crystalline phase changes were assessed using micro-Raman spectroscopy. Specimen preparations were performed in accordance with ISO 14801:2016. Five different ceramic (zirconia) implant designs were divided into the following groups: OPI, BLTPI (BLC, BLT), TLTPI (TLC, TLT). One-way and two-way ANOVA tests were used for comparisons and factor effect analysis. RESULTS:Fracture resistance (N) and bending moment (N cm) differed significantly among the implant groups (p < 0.001), following the order TLTPI (775.2 ± 71 N) > OPI (605.7 ± 37 N) > BLTPI (498.3 ± 93 N). Within the two-piece implants (TPI), tissue-level designs (TL) outperformed bone-level designs (BL), while designs with different abutment screw materials showed no significant difference (p = 0.982). CONCLUSIONS:Within the limitations of this in vitro study, the evaluated zirconia-based OPI, BLTPI, and TLTPI systems demonstrate sufficient fracture resistance to support further clinical investigation. Implant-level design (TL vs. BL) influences mechanical performance, whereas the influence of abutment screw material (ceramic vs. titanium) is less pronounced and varies according to the implant-level design.
OBJECTIVES:To evaluate heat generation during guided implant osteotomy in a standardized in vitro resin-model setup and assess the effects of irrigation technique and model structure on temperature change during drilling. MATERIALS AND METHODS:Standardized solid and bilayered resin mandibular models were fabricated and assigned to no irrigation, external irrigation, or internal irrigation using a 3D-printed guide with irrigation channels. Sequential osteotomy drilling (2.0-4.2 mm) was performed to an 18 mm depth at 1200 rpm. Temperature was measured using infrared thermography and an internal thermistor sensor. Temperature change relative to baseline (ΔT) was the primary outcome. RESULTS:Bilayered models demonstrated lower ΔT than solid models when assessed by infrared thermography (p = 0.009), whereas thermistor measurements showed less consistent differences between model types. Irrigation significantly reduced ΔT, with internal irrigation producing the lowest values. In solid models, mean ΔT decreased from 31.41°C without irrigation to 9.48°C with external irrigation and 3.50°C with internal irrigation. In bilayered models, ΔT decreased from 13.31°C to 2.45°C and 0.84°C, respectively. CONCLUSIONS:Irrigation significantly reduced heat generation during guided implant osteotomy. Internally irrigated guides demonstrated lower temperature change than conventional external irrigation. Bilayered models demonstrated lower temperature changes primarily in infrared thermography measurements and may partially approximate differences in thermal behavior between cortical and trabecular structures under the present experimental conditions.
AIMS:To quantify immediate graft displacement following tension-free flap closure in non-contained alveolar ridge defects regenerated using three membrane fixation strategies in an ex vivo human model. METHODS:Eighteen sites from six fresh cadaveric heads with non-contained defects underwent horizontal guided bone regeneration using deproteinized bovine bone mineral and a collagen membrane stabilized by no fixation (NF), periosteal sutures (PS), or titanium fixation pins (FP). Techniques were applied sequentially. Cone-beam CT scans were obtained at baseline, post-grafting, and after passive closure. Linear ridge width was measured at 12 standardized positions, and graft volumes were segmented from STL reconstructions. Mixed-effects multilevel linear regression assessed width changes, while Friedman and paired Wilcoxon tests evaluated volumetric outcomes, with Tukey-adjusted contrasts for intergroup comparisons. RESULTS:Fixation pins virtually eliminated graft displacement (-6.7 ± 87 mm3) and achieved the highest stability (81.2% ± 8.2%), significantly outperforming periosteal sutures (-96 ± 165 mm3; 70.1% ± 4.5%) and no fixation (-247 ± 150 mm3; 44.4% ± 17.9%) (loss p = 0.030; stability p = 0.002). Ridge collapse was greatest with no fixation (-1.37 ± 0.85 mm) compared with PS (-0.40 ± 0.62 mm) and FP (-0.28 ± 0.61 mm). After adjustment, PS and FP reduced collapse by 0.96 mm (p = 0.012) and 1.11 mm (p = 0.004), respectively. CONCLUSION:Even after passive flap release and tension-free closure, membrane fixation, particularly with titanium pins, provides superior resistance to graft displacement in non-contained defects, while unfixed membranes allow substantial graft loss and are therefore not recommended in non-contained defects.
INTRODUCTION:Accurate implant placement with Computer-Assisted Implant Surgery (CAIS) is critical to ensure long-term success. Dynamic-CAIS systems enhance surgical precision through real-time feedback, though comparative data on their accuracy and efficiency remain limited. This study evaluated how different registration methods in d-CAIS systems influence implant placement accuracy and procedural time. MATERIALS AND METHODS:In this laboratory study, three registration methods were assessed: ND group, XC group, and XM group. Five experienced operators placed 25 implants per group (75 total) in partially edentulous maxillary models. Postoperative CBCT scans were used to measure deviations at the implant entry point, apex, vertical depth, and angle. One-way ANOVA and Tukey's HSD test were used for statistical analysis. RESULTS:Mean 3D deviations at the implant entry point were 1.06 mm (ND), 0.71 mm (XC), and 0.90 mm (XM); at the apex 1.23 mm, 0.83 mm, and 1.07 mm, respectively. Vertical depth deviations at the apex were similar across groups: 0.61 mm (ND), 0.59 mm (XC), and 0.64 mm (XM). Angular deviation was highest in the ND group (2.96°) compared to XC (1.17°) and XM (1.02°), with a significant difference between ND and XM (p = 0.028). The average procedural time was shortest in the XM group (7.20 ± 2.48 min), though differences were not statistically significant. CONCLUSIONS:Although registration methods minimally affect overall accuracy, system-specific factors may influence angular deviation. Future studies should prioritize clinical trials with larger sample sizes and explore the influence of operator experience and learning curves.
OBJECTIVES:This study evaluated the accuracy, time efficiency, and workflow consistency of artificial intelligence (AI)-assisted versus human expert (HI) implant planning in the esthetic anterior maxilla. MATERIAL AND METHODS:Thirty-five single-tooth anterior maxillary cases with paired cone beam computed tomography (CBCT) and intraoral scans (IOS) were retrospectively recruited. A hybrid AI framework (Relu Automate), integrating rule-based constraints (≥ 2 mm labial bone, ≥ 1 mm palatal bone) with deep learning segmentation, was compared with conventional HI. The performance of each planning approach was evaluated based on the following: coronal and apical linear deviations, angular deviation, bone thickness, wax-up alignment, surgical guide fit, planning time, and consistency. Statistical analyses were performed with a significance level of 5% (α = 0.05). RESULTS:AI-assisted planning demonstrated clinically acceptable accuracy with mean coronal, apical, and angular deviations of 0.96 ± 0.6 mm, 1.24 ± 0.66 mm, and 4.3° ± 2.9°, respectively, meeting clinical thresholds in 94.3% (coronal), 85.7% (apical), and 94.3% (angular) of cases. Bone thickness measurements were equivalent between groups (labial: 2.0 mm for both groups; palatal: 1.5 mm AI versus 1.3 mm HI; p > 0.05). AI-assisted planning decreased the median planning time by 41.4% (p < 0.0001) while achieving perfect consistency compared to human experts (p < 0.05). ICC analysis revealed excellent agreement (≥ 0.9) across all spatial coordinates between AI and HI planning. CONCLUSIONS:AI-assisted implant planning achieved accuracy comparable to expert planning with improved efficiency and consistency, while AI-designed surgical guides demonstrated fit comparable to human-designed guides in the maxillary esthetic zone.
OBJECTIVES:The study aimed to explore the changes in the height of the soft tissue around the healing abutment at different time points after second-stage implant surgery. METHODS:Cone-beam computed tomography (CBCT) data were collected at baseline (second-stage surgery), and intraoral scans were obtained at baseline and multiple follow-up visits: after suture removal (1 week post-surgery), during impression taking, and immediately before performing restoration. Patients were grouped based on the time of impression taking (1 or 2 weeks post-suture removal: 1I or 2I), and further subgrouped according to the timing of performing restoration (2, 3, or 4 weeks post-impression: 2R, 3R, or 4R). Digital datasets were superimposed using tooth-supported reference areas before the intraoral height of the healing abutment and the supracrestal tissue height (STH) were measured at the mesial, distal, buccal, and lingual sites at the different time periods. RESULTS:A total of 76 patients with 102 implants were enrolled in the study; specifically, 22 were in the 1I2R group, 18 in 1I3R, 14 in 1I4R, 14 in 2I2R, 18 in 2I3R, and 16 in 2I4R. The STH changes of 2I3R group were (0.37 ± 0.13), (0.41 ± 0.21), (0.43 ± 0.17), (0.43 ± 0.20) mm at the mesial, distal, buccal, and lingual sites, which showed no statistically significant differences with 2I4R group whose STH changes were (0.35 ± 0.13), (0.43 ± 0.22), (0.39 ± 0.16), (0.41 ± 0.14) mm, respectively. the changes of these two groups were Larger Than Other groups, with significant differences (p < 0.01). CONCLUSIONS:Within the study limits, STH around healing abutment tended to stabilize approximately 6 weeks after second-stage surgery.
OBJECTIVE:To determine the influence of an intermediate prosthetic abutment on peri-implant marginal bone loss (MBL) around two implant-supported fixed restorations in the posterior area. MATERIAL AND METHODS:This study included patients with partial edentulism requiring two implants in the posterior maxilla or mandible. All implants were bone-level tapered implants, placed through a fully guided approach and finalized with a CAD/CAM temporary and final full zirconia restoration. The total sample comprised 30 patients (60 implants), divided into a Control group (direct to implant connection, non-intermediate abutment; 12 patients, 24 implants) and a Test group (intermediate abutment; 18 patients, 36 implants). The Test group was further divided into two abutment height subgroups: 1 mm (7 patients) and 2.5 mm (11 patients). MBL was measured using periapical x-ray imaging on the day of surgery, at definitive crown delivery, and at 4, 6, 12, and 24 months post-surgery. RESULTS:The Test group (intermediate abutment) had lower MBL (0.83 ± 0.25 mm) than the Control group (1.17 ± 0.35 mm; p = 0.001). The secondary analysis of the abutment height subgroups did not differ significantly in MBL, although values showed a trend towards a more favorable for the highest intermediate abutment. CONCLUSIONS:This randomized clinical trial demonstrated that direct implant connection prosthesis induced greater MBL around implants in splinted crowns for an implant-supported fixed restoration when compared with the use of an intermediate abutment. TRIAL REGISTRATION:ClinicalTrials.gov ID: NCT06017115.
