The International Journal of Oral & Maxillofacial Implants, 04/2025

Purpose: To evaluate the outcome of implant-supported overdentures using telescopic crowns for the treatment of edentulous patients with an immediate loading protocol. Materials and Methods: This study was conducted on 22 patients with edentulous mandibles visiting the Department of High Technique at the National Hospital of Odonto- Stomatology in Ho Chi Minh City, Vietnam, for prosthodontic rehabilitation. Each patient received four interforaminal implants. An immediate loading protocol was applied, and Ankylos SynCone coping systems (Dentsply Sirona) were used to connect the prostheses and implants. The survival rates of the implants and prostheses, as the primary outcome, were evaluated postoperatively at 6 months, 1 year, and 2 years. Peri-implant tissue condition, peri-implant bone loss, and patient satisfaction were the secondary outcomes. Results: The implant survival rate was 98.9%, with one failed implant. The peri-implant bone loss changes after 6 months, 1 year, and 2 years were 0.07 ± 0.22 mm, 0.12 ± 0.3 mm, and 0.15 ± 0.2 mm, respectively. No gingival hyperplasia was recorded. The prosthesis survival rate was 86.4%, with one fractured overdenture, one overdenture relining, and one abutment fracture. Conclusions: Mandibular rehabilitation using implant-supported overdentures with telescopic crowns and an immediate loading protocol showed high survival rates for both the implants and prostheses at the 2-year follow-up.  Parole chiave: edentulous mandible, implant survival rate, immediate loading, implant-supported overdenture, telescopic denture

Purpose: To evaluate the survival rates and risk factors associated with resorbable blast media (RBM) surface dental implants. Materials and Methods: A total of 1,130 RBM surface implants with hybrid macrogeometry were placed in 260 patients, with a follow-up ranging from a minimum of 26 months to a maximum of 120 months. Implant survival and failure rates were analyzed over an average 60-month follow-up. Failure rates were examined based on implant length, patient sex, and sinus elevation procedures. Additional factors such as patient age, implant placement timing (immediate vs delayed), GBR, implant diameter, and implant location were assessed to determine their impact on long-term implant success. Results: The overall survival rate for the implants was 94.4%, with most failures occurring within the first 12 months postoperatively. Male patients experienced significantly higher failure rates (7.36%) than female patients (4.0%). Short implants (8 mm) were particularly vulnerable to failure, with an 8.65% failure rate. Sinus augmentation procedures also presented an increased risk, with 10% failure for lateral sinus augmentation and 9.78% failure for crestal sinus elevation. In contrast, factors such as patient age, timing of implant placement, GBR, implant diameter, and implant location did not significantly influence failure rates. Notably, narrow-diameter implants (3.3 and 3.7 mm; n = 97) in the molar region did not increase the risk of failure, with only 5 experiencing failure. Failures after prosthetic loading were most common after about 3 years. Conclusions: This study confirms the long-term viability of RBM surface implants, with high survival rates when early failures are mitigated. Short implants and sinus elevation procedures pose greater risks of failure, particularly in the early stages. However, simultaneous GBR and sinus elevation procedures did not significantly impact long-term outcomes, affirming the safety and efficacy of these complex interventions. Parole chiave: failure analysis, guided bone regeneration, immediate loading, immediate placement, implant survival, RBM surface, sinus elevation

Purpose: To assess the efficacy and safety of a sticky dual-phase porcine-derived bone substitute compared to a similar dual-phase xenogeneic non-adhesive bone graft in the presence of induced perforations of the sinus membrane during sinus elevation procedures in a split-mouth rabbit model. Materials and Methods: Bilateral sinus floor elevations were performed in 12 rabbits. The sinus mucosa was intentionally perforated using a blade on both sides and randomly filled with either a corticocancellous bone embedded in a 20% thermosensitive gel (sticky bone test group [GTO]) or a corticocancellous bone and 10% collagen (control group [mp3]). Healing progress was evaluated after 2 and 10 weeks in 12 animals (6 in each group) with CBCT imaging, microcomputed tomography (microCT), and histologic assessments. Results: One animal of the 2-week group died but was substituted. No other complications were observed. At the 2-week time point, CBCTs revealed that biomaterial particles were observed in the vicinity of the sinus membrane in two out of six sinuses of each group but never dispersed into the sinus. MicroCT and histology consistently revealed few granules beyond the elevated region. Histologically, five sinuses in the mp3 group and two sinuses in the GTO group exhibited granules outside the elevated region but in the vicinity of the perforations. In the 10-week groups, the number of affected sinuses decreased to one in the mp3 group and two in the GTO group. Throughout all observations, the graft granules consistently resided proximate to the elevated region. MicroCT demonstrated a reduction in the volume of the elevated region by approximately 12% after 2 weeks and 50% to 54% after 10 weeks. Conclusions: The use of both sticky and non–sticky bone substitutes was observed to prevent a substantial amount of particles from extruding through an induced perforation of the sinus membrane. This suggests that it could be possible to use a sticky bone substitute as an alternative to a barrier membrane to avoid the extrusion of bone granules in the presence of accidental perforation of the sinus membrane in clinical practice. After 10 weeks of healing, the volume of the elevated region decreased by approximately 50%, possibly due to biomaterial resorption and loss through the surgically created perforation. Parole chiave: bone substitute, histomorphometric, sinus membrane perforation, sinus elevation, sticky bone

Purpose: To investigate the interplay between inflammation and differentiation upon implantation, dental pulp stem cells (DPSCs) were cultured on 3D-printed titanium owning an internal open cell form, administering osteogenic factors by a liposomal formulation (LipoMix) compared to traditional delivery of differentiation medium (DM). Materials and Methods: Osteogenic differentiation was evaluated via western blot by measuring β1 integrin expression and real-time reverse transcription-polymerase chain reaction (RT-PCR), as well as measuring SP7 and type 1 collagen gene expression. In addition, angiogenesis was characterized by measuring vascular endothelial growth factor (VEGF) secretion levels. Matrix mineralization was assessed by means of Alizarin red staining, cell adhesion, and inflammation responses through western blot, enzymatic, and enzyme-linked immunosorbent assays (ELISA) that evaluated Nrf2 expression, catalase activity, and prostaglandin E2 (PGE2) secretion, respectively. Results: LipoMix enhances cell proliferation and adhesion, as revealed by increased β1 integrin expression. Mineralized matrix deposition, SP7 gene expression, type 1 collagen release, and alkaline phosphatase activity appeared to increase in the LipoMix condition. Additionally, the redox-sensitive transcription factor Nrf2 was overexpressed at the earliest experimental times, triggering the catalase activity. Conclusions: The data reported confirmed that internal topography and post-production treatments on Ti surfaces dynamically and positively conditioned the DPSC progress toward the osteogenic phenotype; moreover, the combination with LipoMix quickened the positive modulation of inflammation under osteogenic conditions. Therefore, the development of customized surfaces along with the administration of differentiating factors enclosed in a liposomal delivery system could represent a promising and innovative tool in regenerative dentistry. Parole chiave: osteogenic differentiation, NF-E2-related factor 2, liposomal formulation, stem cells, regenerative dentistry

Purpose: To assess the roughness and hydrophilicity of nine types of dental implant surfaces, examine the presence of contaminants—such as carbon and oxygen—on these surfaces, and explore potential correlations among these characteristics across the analyzed surfaces. Materials and Methods: The analyzed surfaces were as follows: machined (turned) (MI) (Implacil De Bortoli), blasted with titanium (Ti) oxide (TOI) (Implacil De Bortoli), blasted with Ti oxide and acid etched (TOAEI) (Implacil De Bortoli), blasted with zirconia (Zr) and acid etched (ZAED) (DSP Medical), coated with calcium phosphate (CPD) (DSP Medical), subjected to an experimental treatment (patent pending; XD) (DSP Medical), double acid etched and activated with hydroxyapatite nanocrystals (DAEHAS) (S.I.N.), double acid etched (DAES) (S.I.N.), and untreated surface of the Plenum implant (AMP) produced by additive manufacturing (Plenum). Four disc-shaped specimens of each surface type were used in the hydrophilicity analyses, and five disc-shaped specimens of each surface type were used in the roughness analyses. Roughness was evaluated by optical profilometry and scanning electron microscopy, hydrophilicity was determined using the sessile-drop technique, and the chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The Kruskal-Wallis, Mann-Whitney U, and Spearman correlation tests were employed to analyze the data (P < .10). Results: Significant differences were observed among the analyzed surfaces in terms of both roughness and hydrophilicity (P < .001). The surface that exhibited the highest roughness was AMP, whereas the greatest hydrophilicity was exhibited by the CPD surface. Correlations between roughness and hydrophobicity were only observed for the MI surface (r = 0.936, P = .009), ZAED surface (r = 0.957, P = .004), and DAES surface (r = 0.964, P = .005). The carbon concentration observed on the CPD surface was lower than that observed on the other surfaces, whereas the oxygen concentrations were similar across all groups. No correlations were observed between the presence of contaminants and the roughness or hydrophilicity characteristics. Conclusions: The roughness and hydrophilicity values exhibited considerable variation among the tested surfaces. Aside from the CPD surface, comparable concentrations of carbon and oxygen were detected. Although correlations between roughness and hydrophilicity were observed only for the ZAED, DAES, and MI surfaces, these correlations were inadequate to establish a causal relationship between the two surface characteristics.  Parole chiave: cell adhesion, dental implants, osseointegration, surface properties, wettability

Purpose: To evaluate how implant analog design and printing layer thickness can affect the linear and angular accuracy of implant analogs in additively manufactured casts compared to conventional implant analogs in stone casts. Materials and Methods: A reference cobalt chromium mandibular model with a single implant was digitized using an industrial optical scanner and scan bodies that were compatible with a pressure/friction fit (S) or a screw retained (N) implant analog for direct digital workflow. These scans were used to fabricate casts with 50-µm (S-50 and N-50) (n = 10) and 100- µm (S-100 and N-100) layer thickness (n = 10). A total of 10 stone casts were made after single-step closed-tray polyvinyl siloxane impressions of the model (CNV) were made. All casts were digitized with the same metal scan body and scanner used to digitize the master model. These scans were then superimposed over the scan of the master model to measure the linear (x, y, and z- axes) and angular (XY and YZ planes) deviations (Geomagic Control X). The precision of measured deviations was defined with the average deviation values. Generalized linear model analysis was used to compare the deviations within implant analogs for direct digital workflow, while a one-way analysis of variance (ANOVA) and Dunnett’s test were used to compare these analogs and conventional analogs (α = .05). Results: The analog design affected the linear deviations (y-axis), while the interaction between the analog design and the layer thickness affected the angular deviations (XY plane, P ≤ .030) of the analog design. S analogs had lower linear and angular deviations than N analogs, and S-50 led to lower angular deviations than N-50 (P ≤ .030). CNV led to higher linear accuracy (y-axis) than N-50, N-100, and S-100 and led to lower angular deviations than all test groups (XY plane) (P ≤ .025). Conclusions: The analogs in S-50 casts had positional trueness similar to or higher than those in other test groups, and their accuracy was mostly similar to those in CNV casts. Implant analogs for direct digital workflow deviated more toward lingual and gingival, and conventional analogs deviated more toward buccal, occlusal, and distal. All analogs had a tendency to tilt toward the lingual and distal directions.  Parole chiave: analog design, angular deviation, implant analog, layer thickness, linear deviation

Purpose: To evaluate implant success rates and facial mucosal profile changes in maxillary single immediate implant placement and provisionalization with the socket-shield (IIPP+SS) technique and without the socket-shield (IIPP-SS) technique. Materials and Methods: A total of 30 dental implants in 25 patients were assigned to either the IIPP-SS group (15 implants) or the IIPP+SS (15 implants) group. Clinical and radiographic outcomes were collected preoperatively (T0) as well as at 2-week (T1), 6-month (T6), and 12-month (T12) postoperative follow-ups. The implant success rate, marginal bone level changes, facial mucosal level changes, and papilla level changes were evaluated at different time points. Facial mucosal profile changes were assessed individually for hard and soft tissue zones and as a whole using volumetric analysis. Results: Two implants were excluded (one patient dropped out and one implant failed) from the data analysis in this study, resulting in an overall implant success rate of 96.6% (28/29) after 1 year. Fewer facial mucosal profile changes were noted in the IIPP+SS group than in the IIPP-SS group; however, the difference was only marginally statistically significant (P = .06).  No statistically significant difference was found in the facial mucosal level changes (P = .18) and papilla level changes (P = .67 for the mesial papilla level, P = .41 for the distal papilla level) between the IIPP-SS and IIPP+SS groups. Conclusions: Within the limitations of this 1-year randomized controlled clinical trial, the IIPP+SS group appeared to maintain the implant facial mucosal profile slightly better than IIPP alone. Both treatment modalities provide clinically satisfactory outcomes biologically, functionally, and esthetically.  Parole chiave: dental implants, facial mucosal profile and level, immediate tooth replacement, implant esthetics, socket-shield technique

Purpose: To evaluate the long-term outcomes and assess the risk factors associated with marginal bone loss (MBL) for implant-assisted removable partial denture surveyed crowns (IARPDSCs). Materials and Methods: A total of 51 implants were placed in 14 partially or fully edentulous patients and restored using IARPDSCs. Implant crowns or bridges served asabutments for removable partial dentures (RPDs) to enhance their esthetics, comfort, and function. All patients attended regular follow-up appointments every 3 to 6 months for up to 12.5 years, which included professional cleaning and oral hygiene reinforcement. The collected data included patient demographics, treatment modality, arch restoration, Kennedy classification, RPD connection and retention design, opposing dentition, implant characteristics (location, connection type, and diameter), and any complications. The clinical assessments included plaque score, bleeding on probing, probing depth, marginal tissue recession, and keratinized mucosa width. Univariate and multivariate analyses were performed to identify factors influencing the MBL of implants in IARPDSCs. Results: One implant failed during follow-up; thus, the implant survival rate was 98%. All patients were satisfied with their prostheses and reported only minor complications. Univariate analysis showed a significantly higher MBL in maxillary implants than in mandibular implants (P = .045). Multiple regression analysis revealed that bruxism (P = .002) and maxillary implants (P = .013) were significantly associated with a higher MBL. Female sex (P = .051) and anterior implants (P = .058) exhibited an association with higher MBL. Conclusions: Within the limitations of this retrospective clinical study, IARPDSCs demonstrated predictable long-term success in carefully selected and well-maintained patients. Parole chiave: alveolar bone, dental implantation, mandible, maxilla, survival, removable partial denture

Purpose: To verify whether measuring the implant stability quotient (ISQ) at the abutment level is identical to the value obtained at the implant level. Materials and Methods: A retrospective clinical study and in vitro study were performed. For each study, the ISQ measured at the implant level defined the control groups. The values obtained after the abutment seating comprised the test groups, which were divided into three test subgroups corresponding to three different multiunit abutments: (1) straight multiunit abutments (MUAS) and (2) 17-degree angled multiunit abutments (MUA17), both with a 2.5-mm collar, and (3) 30-degree angled multiunit abutments (MUA30) with a 3.5-mm collar. Data was compared by the Wilcoxon signed-rank test and Kruskal-Wallis test. Results: The control group (59 implants; 79.14 [SD = 3.39]) showed significantly higher measurements than the test group (73.22 [SD = 8.54]). In addition, the subgroup measurements from MUA17 (16 abutments; 66.38 [SD=1.20]) and MUA30 (16 abutments; 69.19 [SD = 0.96]) were lower than the control group. No differences were found in the MUAS (27 abutments; 79.67 [SD = 1.48]) subgroup when compared with the control group (correlation of 0.68). Regarding the in vitro analysis, the control group measurements (36 implants; 68.02 [SD = 1.81]) were significantly higher than the test group (62.57 [SD = 2.87]). The control group measurements were also higher than each test subgroup (12 abutments each): MUAS (65.44 [SD = 0.73]), MUA17 (60 [SD = 0.43]), and MUA30 (62.29 [SD= 0.35]). Conclusions: Based on the results of this study, determining the ISQ at the abutment level results in lower ISQ values than the implant level; note that these measurements may not accurately reflect the actual implant stability. Future research is needed to explore whether and under what circumstances a correlation exists between the ISQ measured at the implant level and abutment level. Parole chiave: abutment level implant stability, implant stability, implant stability quotient, one abutment one time

This technical note serves as a practical guide for clinicians aiming to provide solutions to optimize the precision of static computer-assisted implant surgery (sCAIS) and the success of implant placement in free-end situations. Five methods are introduced for enhancing surgical guide stabilization and improving the accuracy of implant placement in situations lacking stabilizing adjacent teeth. These techniques include the use of keratinized soft tissue, implant-borne stabilizers, lateral fixation pins, transitional implants, and digital bone segmentation for guide support. Each method is evaluated for its potential to address the specific challenges faced in sCAIS, aiming to contribute to the field through practical solutions for clinicians.

Purpose: To analyze the clinical and radiographic outcomes of single-unit implant-supported restorations comprehensively. Materials and Methods: In this retrospective study, 100 patients who had undergone 12 months of implant-supported single-unit fixed prosthetic treatment were scanned from the archives and were included in this study. Implant success and survival rates were assessed according to the consensus decisions published at the International Oral Implantology Congress in 2007. Prosthetic complications such as chipping, screw loosening, and decementation were also evaluated. In addition, success rates, survival rates, and prosthetic compositions were associated with a few surgical and prosthetic parameters. Results: According to the success and survival criteria, 88% of the implants were successful, 10% had satisfactory survival, and 2% had compromised survival. The risk of satisfactory or compromised survival was 62.5 times higher in individuals with inadequately keratinized mucosa compared to those with adequately keratinized mucosa (P < .001). This risk was also 5.736 times greater for extractions due to periodontal disease versus endodontic reasons (P = .010) and 4.629 times higher for implants with diameters < 3.75 mm compared to those between 3.75 mm and 5 mm (P = .037). Screw loosening was observed in 15% of the evaluated restorations, decementation in 13%, and chipping in 4%; note that the risk of screw loosening was 4.444 times higher for screw-retained abutments compared to standard abutments (P = .015). Conclusions: Insufficient keratinized mucosa, periodontal problems leading to tooth extractions, and the use of narrow-diameter implants can negatively affect the success of implant procedures. Loosening in screw-retained restorations is due solely to screw loosening, which is a high risk for screw-retained restorations. Loosening in cement-retained restorations, on the other hand, is caused by the decementation of the prosthetic restoration or loosening of the abutment screw supporting the restoration.  Parole chiave: peri-implantitis, prosthetic procedure, single implant

Purpose: To evaluate four formulations of tetracalcium phosphate combined with phosphoserine (TTCP-PS) in comparison to the conventional grafting materials bioglass (BG) and deproteinized cancellous bovine bone with a bioresorbable collagen membrane in standardized defects created in the angle of the rat mandible. Materials and Methods: TTCP-PS is a synthetic, injectable, cohesive, self-setting, mineral-organic wet-field adhesive. Microcomputed tomography (microCT) and histomorphometry were used to evaluate bone replacement with each of these materials after in vivo residence of either 4 or 12 weeks. Results: Specific TTCP-PS formulations can form bone comparable to conventional materials in an osteopromotive mechanism but with the advantage of having cohesive and adhesive properties. Conclusions: This study showed the potential for TTCP-PS to be used as a viable candidate for bone grafting procedures.  Parole chiave: biocompatible biomaterials, bone adhesive, bone graft resorption, bone regeneration, bone-to-implant interface, calcium phosphate, cohesive bone graft, histomorphometry, injectable graft material, mineral-organic cement, mandibular defect model, microCT, osteopromotion, preclinical in vivo study, tetracalcium phosphate phosphoserine (TTCP-PS)