International Journal of Oral & Maxillofacial Implants最新文献

Purpose: To evaluate the effect of implant body diameter, platform diameter, and the use of transepithelial components on implant-abutment connection (IAC) microgap width.

Materials and methods: In total, 16 tests were performed on four commercial dental restoration models (BTI Biotechnology Institute). Different static loads were applied to the embedded implants according to the International Organization for Standardization (ISO) 14801, using a customized loading device. Measurements of the microgap were taken by means of highly magnified x-ray projection in situ in a micro-CT scanner. Regression models were obtained and compared through an analysis of covariance (ANCOVA). To quantify the effect of each variable, t tests (α = .05) of experimental results were performed.

Results: Under 400 N, using a transepithelial component for the dental restoration, the microgap width was reduced by 20% (P = .044). Meanwhile, a 22% microgap reduction was observed when the implant body diameter was increased by 1 mm (P = .024). Finally, increasing the platform diameter by 1.4 mm led to a microgap reduction of 54% (P = .001).

Conclusion: The use of a transepithelial component in dental restorations reduces the microgap width in IACs. Furthermore, given sufficient space for the implantation, larger implant bodies and platform diameters can also be used for this purpose. Int J Oral Maxillofac Implants 2023;38:489-495. doi: 10.11607/jomi.9855.

Purpose: This randomized clinical trial aimed to assess esthetic and soft and hard tissue outcomes 6 months after immediate implant placement using vestibular socket therapy (VST) (test) versus partial extraction therapy (comparator) in intact thin-walled fresh extraction sockets in the esthetic zone.

Materials and methods: Twenty-four patients with hopeless maxillary anterior teeth requiring immediate implant placement were randomly assigned to two equal groups to receive either VST or partial extraction therapy. Definitive restorations were delivered after 3 months. Pink esthetic scores (PESs) and vertical soft tissue alterations in millimeters were measured 6 months after restoration using intraoral digital scans of the distal papilla, midfacial gingival margin, and mesial papilla. Facial bone thickness was measured using CBCT scans at baseline and after 6 months. Implant survival and peri-implant pocket depth were assessed.

Results: Both groups showed 100% implant survival after 6 months. The overall PESs after 6 months were 12.67 (± 1.3) in the VST group, while the partial extraction therapy group score was 13.17 (± 1.19), with no significant difference between them (P = .02). The mean (± SD) vertical soft tissue measurements for the VST group were 0.08 (± 0.55), 0.01 (± 0.73), and -0.03 (± 0.52) mm, and for the partial extraction therapy group, they were -0.24 (± 0.25) mm, -0.20 (± 0.10) mm, and -0.34 (± 0.13) mm for the mesial papilla, midfacial gingival margin, and distal papilla, respectively. No significant differences were observed between the groups at any of the reference points (P ± .05). Both techniques demonstrated a significant gain in millimeters of labial bone thickness after 6 months compared to baseline (P ± .05). Regarding VST, the apical, middle, and crestal mean bone gain was 1.68 (±± 2.73), 1.62 (±± 1.35), and 1.33 (±± 1.22) mm, respectively, while partial extraction therapy showed 0.58 (± 0.62), 1.27 (± 1.22), and 1.53 (± 1.24) mm, respectively, with no significant difference detected between them (P ≥ .05). Additionally, the mean (± SD) peri-implant pocket depth after 6 months for VST was 2.16 (± 0.44) and 2.08 (± 1.02) mm for partial extraction therapy with no significant difference between them (P = .79).

Conclusion: This investigation suggests that both VST and partial extraction therapy preserved alveolar bone structure and peri-implant tissues following immediate implants. The novel VST might be considered a predictable alternative treatment approach for immediate implant placement in intact thin-walled fresh extraction sockets in the esthetic zone. Int J Oral Maxillofac Implants 2023;38:468-478. doi: 10.11607/jomi.9973.

Purpose: To analyze the success and survival of splinted and nonsplinted implants.

Materials and methods: A total of 423 patients (n = implants: 888) were included in the study. The success and survival of implants for 15 years were analyzed using a multivariable Cox regression model, and the significant effect of the splinting of prostheses and other risk factors were evaluated.

Results: The cumulative success rate was 34.2%: 33.2% in nonsplinted (NS) and 34.8% in splinted implants (SP). The cumulative survival rate was 92.9% (94.1%, NS; 92.3%, SP). Whether to splint was not related to the success and survival of implants. The smaller the implant diameter, the lower the survival rate. The crown length and implant length were significantly associated only with NS implants: The longer the crown length and the shorter the implant length, the greater the risk of implant failure. The emergence angle (EA) and the emergence profile (EP) had a significant effect on only the SP implants: EA3 showed a higher risk than EA1, and EP2 and EP3 had a higher risk of implant failure.

Conclusion: Crown length and implant length affected only the nonsplinted implants: The higher the crown length and the shorter the implant length, the greater the risk of implant failure. A significant effect for emergence contour was found only in SP implants: the implants restored with prostheses with EA ≥ 30 degrees on both the mesial and distal sides, and convex EP on at least one side had higher risks of failure. Int J Oral Maxillofac Implants 2023;38:443-450. doi: 10.11607/jomi.10054.

Purpose: To develop a surface coating of sol-gel 70S30C bioactive glass (BAG) nanoparticles on titanium disks and dental implants and characterize the BAG coating from the standpoint of average surface roughness, adhesion strength, and coating stability upon implant insertion under clinical settings.

Materials and methods: BAG was prepared using a modified sol-gel technique, then milled into nanoparticles. The resultant powder was characterized in terms of phase structure, composition, and particle size. Titanium disks and dental implants were coated with BAG nanoparticles via electrophoretic deposition. Surface characterization of coated implants was conducted. Uncoated and BAGcoated implants were examined for average surface roughness using a confocal laser scanning microscope. Pull-off tests were conducted to measure the adhesion strength of the BAG coating to the underlying disks. To measure the amount of coating loss and evaluate the effect of insertion on coating thickness, coated implants were inserted under clinical settings into artificial and natural bones.

Results: BAG nanoparticles had an amorphous structure with particle sizes < 20 nm in diameter. Electrophoresis resulted in a continuous coating that covered the whole implant surface. Microscopic analysis confirmed the porous nanostructure of the BAG coating, which formed a homogenous surface with microcracks. The BAG coating had a uniform thickness of 35.38 ± 4.67 μm. The average surface roughness was significantly lower for BAG-coated implants, with less surface irregularities (3.34 ± 0.45 μm for uncoated implants, 1.45 ± 0.23 μm for BAG-coated implants). An adhesion strength of 18.51 ± 3.37 MPa was recorded for the BAG coating. After insertion into artificial bone, 66.23 ± 10.23% of the coating weight remained on the implant surface. A reduction in the thickness of the BAG coating only occurred in sites of high friction with bone after implant insertion into bovine bone.

Conclusions: Coating titanium implants with 70S30C BAG nanoparticles is attainable through electrophoretic deposition and results in a homogenous coating layer with a moderately rough surface, considerable adhesion strength, and high coating stability during implant insertion. Int J Oral Maxillofac Implants 2023;38:591-606. doi: 10.11607/jomi.10272.

Purpose: To compare the frequency of immediate/short-term postoperative bleeding and occurrence of hematomas using tranexamic acid (TXA), bismuth subgallate (BS), or dry gauze (DG) as a local hemostatic agent, and to explore the relation between short-term bleeding and occurrence of intraoral and extraoral hematomas and length of incision, duration of surgery, and alveolar ridge recontouring in patients who were continued on oral anticoagulation therapy.

Materials and methods: Eighty surgical procedures performed in 71 patients were assigned to one of four groups (20 each): control group (patients not on oral anticoagulant therapy) and three experimental groups (patients on oral anticoagulation therapy managed with local hemostatic measures): TXAg, BSg, or DGg. Studied variables were length of incision, duration of surgery, and alveolar ridge recontouring. Short-term bleeding episodes and occurrence of intraoral and extraoral hematomas were recorded.

Results: A total of 111 implants were placed. No significant differences in mean international normalized ratio, duration of surgery, and length of incision were observed among groups (P > .05). Short-term bleeding and intraoral and extraoral hematomas were observed in 2, 2, and 14 surgical procedures, respectively, and did not differ significantly among groups. Overall relation between variables showed no association between extraoral hematomas and duration of surgery/length of incision (P > .05). Association between extraoral hematomas and alveolar ridge recontouring was statistically significant (OR = 26.72). Association with short-term bleeding and intraoral hematomas was not studied due to the small number of events.

Conclusion: Implant placement in warfarin anticoagulated patients without withdrawing oral anticoagulation therapy is a safe and predictable procedure, and different local hemostatic agents (TXA, BS, and DG) are effective in managing postoperative bleeding. Development of hematomas may be higher in patients undergoing alveolar ridge recontouring. Further studies are necessary to confirm these results. Int J Oral Maxillofac Implants 2023;38:545-552. doi: 10.11607/jomi.9846.

Purpose: To develop a machine learning model that can predict dental implant failure and peri-implantitis as a tool for maximizing implant success.

Materials and methods: This study used a supervised learning model to retrospectively analyze 398 unique patients receiving a total of 942 dental implants presenting at the Philadelphia Veterans Affairs Medical Center from 2006 to 2013. Logistic regression, random forest classifiers, support vector machines, and ensemble techniques were employed to analyze this dataset.

Results: The random forest model possessed the highest predictive performance on test sets, with receiver operating characteristic area under curves (ROC AUC) of 0.872 and 0.840 for dental implant failures and peri-implantitis, respectively. The five most important features correlating with implant failure were amount of local anesthetic, implant length, implant diameter, use of preoperative antibiotics, and frequency of hygiene visits. The five most important features correlating with peri-implantitis were implant length, implant diameter, use of preoperative antibiotics, frequency of hygiene visits, and presence of diabetes mellitus.

Conclusion: This study demonstrated the ability of machine learning models to assess demographics, medical history, and surgical plans, as well as the influence of these factors on dental implant failure and peri-implantitis. This model may serve as a resource for clinicians in the treatment of dental implants. Int J Oral Maxillofac Implants 2023;38:576-582. doi: 10.11607/jomi.9852.

Purpose: To demonstrate the likelihood of the polyetheretherketone (PEEK), zirconia (ZrO2), and titanium (Ti) disks to support proliferation and hemidesmosome formation of gingival cells.

Materials and methods: Water contact angle was performed on each material, and surface roughness (Ra) was measured. Scanning electron microscopy and x-ray photoelectron spectroscopy were used. Later, oral keratinocyte cells were cultured on disks, and metabolic activity and expression of hemidesmosome markers, integrin α6 and β4, in relation to the biomaterial disks at 1, 3, and 5 days of cell culture were quantified. Tissue culture polystyrene was used as the control. Statistical analysis was performed with analysis of variance (ANOVA) with Tukey post hoc comparison test. A P value of < .05 was considered statistically significant.

Results: The water contact angle ranged from 70.2 degrees (Ti) to a maximum of hydrophobicity of 93.3 degrees (PEEK). Ra was highest on ZrO₂, followed by PEEK. Ti showed the most keratinocyte metabolic activity at 1, 3, and 5 culture periods. Contrarily, ZrO₂ and PEEK disks had lower keratinocyte metabolic activity at all observation times, with no statistical differences between both groups. Integrin α6 and β4 expression was highest on TCPS and ZrO₂ compared to Ti and PEEK.

Conclusion: Keratinocytes proliferated faster on Ti than on ZrO₂ and PEEK substrates, and expression of hemidesmosome formation markers, integrin α6 and β4, were higher on ZrO₂ than either Ti or PEEK. Int J Oral Maxillofac Implants 2023;38:496-502. doi: 10.11607/jomi.9894.

In dental research, it is particularly common for studies to collect data that are fundamentally correlated. Some common dental situations in which correlation arises include patients being observed across multiple teeth and/or across multiple time points, such as before and after treatment, or groups of patients being clustered (ie, familial units). For a number of traditional statistical tests and modeling techniques, the assumption of independence between observations is imperative in order to receive valid results and make accurate conclusions. This article describes how ignoring inherent correlations in data can lead to erroneous results when using traditional methods as well as the types of modeling techniques that are available to handle correlated data. Furthermore, two simulation studies are performed to further illustrate and prove the advantages of adequately handling correlated data in statistical analyses. Int J Oral Maxillofac Implants 2023;38:417-421. doi: 10.11607/jomi.10285.

Purpose: To evaluate the safety and performance of a potential novel strategy to resolve the above scenario by simultaneously performing implant-related surgery and endodontic microsurgery (EMS).

Materials and methods: A total of 25 subjects requiring GBR during implant placement in anterior areas were allocated into two groups. In the experimental group (adjacent teeth with periapical lesions) with 10 subjects, implantation and GBR were performed for edentulous areas with simultaneous EMS for adjacent teeth. In the control group (adjacent teeth without periapical lesions) with 15 subjects, implantation and GBR were performed for edentulous areas. The clinical outcomes, radiographic bone remodeling, and patient-reported outcomes were assessed.

Results: Within a 1-year follow-up, the implant survival rate was 100% in both groups, with no significant difference regarding complications. All teeth achieved complete healing following EMS. Repeated analysis of variance (ANOVA) measurements revealed a significant change over time in horizontal bone widths and postoperative patient-reported outcomes, but no intergroup statistically significant differences (P > .05) in horizontal bone widths and visual analog scale scores of pain, swelling, and bleeding were observed. Likewise, the bone volumetric decrease (7.4% ± 4.5% in the experimental group and 7.1% ± 5.2% in the control group) from T1 (suture removal) to T2 (6 months after implantation) revealed no intergroup differences. The horizontal bone width gain at the implant platform was slightly lower in the experimental group (P < .05). Interestingly, the color-coded figures of both groups showed a facial reduction of grafted material in edentulous areas. However, the apical regions following EMS exhibited stable bone remodeling in the experimental group.

Conclusion: This novel approach to address the problem involving implant-related surgery close to the periapical lesion of adjacent teeth appeared safe and reliable (no.: ChiCTR2000041153). Int J Oral Maxillofac Implants 2023;38:533-544. doi: 10.11607/jomi.9839.

Purpose: To assess and quantify survival rates and marginal bone levels (MBLs) of implants placed using guided surgery with a flapless approach vs traditional flap elevation. Materials and Methods: An electronic literature search was conducted in PubMed and the Cochrane Library and refereed by two independent reviewers. Data were synthesized for MBL and survival rates for "flapless" vs traditional "flap" implant placement approach groups. Meta-analyses and nonparametric tests for differences between groups were performed. Rates and types of complications were compiled. The study was conducted under PRISMA 2020 guidelines. Results: A total of 868 records were screened. Full-text review of 109 articles resulted in a total of 57 included studies (50 included for quantitative synthesis and analysis). The survival rate was 97.4% (95% CI: 96.7%, 98.1%) for the flapless approach vs 95.8% (95% CI: 93.3%, 98.2%) for the flap approach; weighted Wilcoxon rank sum test for significance was P = .2339. MBL for the flapless approach was 0.96 mm (95% CI: 0.754, 1.16) vs 0.49 mm (95% CI: 0.30, 0.68) for the flap approach; weighted Wilcoxon rank sum test for significance was P = .0495. Conclusion: The outcomes of this review have suggested that surgical guided implant placement can be used as a reliable method regardless of approach. Additionally, flap and flapless approaches provided similar implant survival rates, but the flap technique provided a slightly better MBL than the flapless approach.