International Journal of Oral & Maxillofacial Implants最新文献

Purpose: To examine and compare stress values of implants, highest tensile and compressive values, and their distribution in cortical and trabecular bone near and around the implant region using different materials (aramid fiber, glass fiber, polyethylene fiber, carbon fiber, and cobalt-chromium [Co-Cr] alloy). Four dental implants were placed in the maxillary crest with two different location scenarios, and the 3D finite element analysis method was used to evaluate stress characteristics.

Materials and methods: Two maxillary models were created in which the implants were placed in different locations (lateral and first premolar, canine and second premolar). Four implant-supported overdenture prostheses were reinforced, applying Co-Cr alloy, glass fiber, aramid fiber, and carbon fiber. Static loads of 200 N were applied on the first molar region using the food stuff method. Stresses around the implants and denture-bearing areas and compression and tensile stresses on the cortical and trabecular bone were evaluated.

Results: In all tested models, the highest von Mises stresses on implants and prostheses were observed in aramid fiber-reinforced overdentures. This was followed by glass fiber, Co-Cr alloy, and carbon fiber groups, respectively. It was observed that the lowest tensile and highest compression stress values in cortical and trabecular bone occurred in prostheses supported with carbon fiber. In all infrastructure materials, the design in which the implants were placed bilaterally in the lateral teeth and the first premolar region was found to be advantageous in terms of stress levels and distribution.

Conclusion: High elastic modulus fiber-reinforced overdenture prostheses transmitted less stress to implants and surrounding tissues than Co-Cr alloy. Anteriorly placed implant design illustrated lower stress values in the prosthesis, implant, and cortical and trabecular bone, and this placement design may increase the survival rates of both dental implants and overdentures. In light of this study, fibers can be recommended for clinical use and securely applied as an alternative material to metal support. Int J Oral Maxillofac Implants 2023;38:523-532. doi: 10.11607/jomi.9946.

Purpose: To quantify the cumulative oral implant survival rates and changes in radiographic bone levels based on the configuration of the implant-abutment connection type over time. Materials and Methods: An electronic literature search was conducted in four databases (PubMed/MEDLINE, Cochrane Library, Web of Science, and Embase), and records were refereed by two independent reviewers based on the inclusion criteria. Data from included articles were grouped by implant-abutment connection type into four categories ([1] external hex; [2] bone level, internal, narrow cone < 45 degrees; [3] bone level, internal wide cone ≥ 45 degrees or flat; and [4] tissue level) and duration of follow-up (short-term 1 to 2 years, mid-term 2 to 5 years, and long-term > 5 years). Meta-analyses were performed for cumulative survival rate (CSR) and changes in marginal bone level (ΔMBL) from baseline (loading) to last reported follow-up. Studies were split or merged as appropriate based on the implants and follow-up duration in the study and trial design. The study was compiled under PRISMA 2020 guidelines and registered in the PROSPERO database. Results: A total of 3,082 articles were screened. Full-text review of 465 articles resulted in a total of 270 articles (representing 16,448 subjects with 45,347 implants) included for quantitative synthesis and analysis. Mean ΔMBL (95% CI) was as follows: short-term external hex = 0.68 mm (0.57, 0.79); short-term bone level, internal, narrow cone < 45 degrees = 0.34 mm (0.25, 0.43); short-term bone level, internal wide cone ≥ 45 degrees = 0.63 mm (0.52, 0.74); short-term tissue level = 0.42 mm (0.27, 0.56); mid-term external hex = 1.03 mm (0.72, 1.34); mid-term bone level, internal, narrow cone < 45 degrees = 0.45 mm (0.34, 0.56); mid-term bone level, internal wide cone ≥ 45 degrees = 0.73 mm (0.58, 0.88); mid-term tissue level = 0.4 mm (0.21, 0.61); long-term external hex = 0.98 mm, 0.70, 1.25); long-term bone level, internal, narrow cone < 45 degrees = 0.44 mm (0.31, 0.57); long-term bone level, internal wide cone ≥ 45 degrees = 0.95 mm (0.68, 1.22); and long-term tissue level = 0.43 mm (0.24, 0.61). CSRs (95% CI) were: short-term external hex = 97% (96%, 98%); short-term bone level, internal, narrow cone < 45 degrees = 99% (99%, 99%); short-term bone level, internal wide cone ≥ 45 degrees = 98% (98%, 99%); short-term tissue level = 99% (98%, 100%); mid-term external hex = 97% (96%, 98%); mid-term bone level, internal, narrow cone < 45 degrees = 98% (98%, 99%); mid-term bone level, internal wide cone ≥ 45 degrees = 99% (98%, 99%); mid-term tissue level = 98% (97%, 99%); long-term external hex = 96% (95%, 98%); long-term bone level, internal, narrow cone < 45 degrees = 98% (98%, 99%); long-term bone level, internal wide cone ≥ 45 degrees = 99% (98%, 100%); and long-term tissue level = 99% (98%, 100%). Conclusion: The configuration of the implant-abutment interface h

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.

Purpose: To analyze the biologic and mechanical complications of splinted and nonsplinted implant restorations.

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

Results: Biologic complications occurred in 38.7% of implants: 26.4% of nonsplinted implants (NS) and 45.4% of splinted implants (SP). Mechanical complications occurred in 49.2% of implants: 59.3% NS and 43.9% SP. Implants splinted with both mesial and distal adjacent implants (SP-mid) had the highest risk of peri-implant diseases. As the number of implants splinted increased, the risk of mechanical complications decreased. Long crown lengths increased the risk of both biologic and mechanical complications.

Conclusion: Splinted implants had a higher risk of biologic complications and lower risk of mechanical complications. The implant splinted to both adjacent implants (SP-mid) had the highest risk of biologic complications. The greater the number of implants splinted, the lower the risk of mechanical complications. Long crown lengths increased the risk of both biologic and mechanical complications. Int J Oral Maxillofac Implants 2023;38:435-442. doi: 10.11607/jomi.10053.

Purpose: To histologically and radiographically investigate the effect of plasma rich in growth factor (PRGF) mixed with bone grafts on ossification in the early period.

Materials and methods: A total of 12 New Zealand male rabbits (weighing between approximately 2.5 to 3 kg) were included in this study. Subjects were randomly divided into two sets of groups: control and experiment. Autograft, DFDBA (demineralized freeze-dried bone allograft), and DBBM (deproteinized bovine bone mineral) were applied to different defects in the control groups, and autograft + PRGF, DFDBA + PRGF, and DBBM + PRGF were applied in the experimental groups. All subjects were euthanized 28 days after surgery. The volumes of the bone, new connective tissue, and new capillaries were evaluated stereologically, and the bone density in the defects was investigated radiographically.

Results: Regarding the stereologic evaluation, the volumes of the bone and capillaries were significantly higher in the experimental groups than in the control groups. In contrast, the connective tissue volume was considerably lower (P < .001, in all groups). Similarly, radiographic examinations showed that the bone density measurements in the experimental groups were higher than in the control groups. However, these differences were statistically significant only between the DFDBA + PRGF and DFDBA groups (P < .011).

Conclusions: The present study provides evidence that the addition of PRGF to autograft, DFDBA, and DBBM enhances osteogenesis in the early period compared to using these grafts alone. It also accelerates the remodeling of connective tissue to bone in defects. Int J Oral Maxillofac Implants 2023;38:569-575. doi: 10.11607/jomi.9858.

Purpose: To assess whether the presence or absence of keratinized tissue height (KTh) may have an influence on marginal bone levels, complications, and implant survival for short implants.

Materials and methods: The study was designed as parallel cohort retrospective research. Short implants with an implant length < 7 mm were considered. One cohort was composed of patients with short implants surrounded by ≥ 2 mm of KTh (adequate KTh); the other cohort included implants with < 2 mm of KTh (not-adequate KTh). Outcome measures were marginal bone level (MBL) changes, failures, and complications.

Results: One hundred ten patients treated with 217 short and extrashort implants (4 to 6.6 mm long) were retrospectively included. The mean follow-up was 4.1 years after prosthetic loading (range: 1 to 8 years). The differences between KTh groups in MBL were not statistically significant at every follow-up considered: 0.05 mm at 1 year (P = .48), 0.06 mm at 3 years (P = .34), 0.04 mm at 5 years (P = .64), and 0.03 at 8 years (P = .82). A total of nine complications were reported: three in the not-adequate KTh group and six in the adequate group; the difference was not statistically significant (OR: 3.03, 95% CI: 0.68 to 13.46, P = .14). Five implants failed due to peri-implantitis, two in the not-adequate KTh group and three in the adequate group, without a statistically significant difference (OR: 2.76, 95% CI: 0.42-17.99, P = .29).

Conclusion: This study showed no statistically significant differences in MBL, complications, and implant failure rates between short implants with adequate or not-adequate KThs. However, given the importance of patient comfort while brushing and plaque accumulation, keratinized tissue grafts could be important in selected patients, especially for those who are severely atrophic, also taking into consideration all the limitations of this study and the mediumterm follow-up. Nevertheless, longer follow-ups, larger numbers of patients, and randomized controlled clinical trials are needed before making more reliable clinical recommendations. Int J Oral Maxillofac Implants 2023;38:462-467. doi: 10.11607/jomi.9918.

Purpose: To evaluate the hard and soft tissue alterations of immediate implant placement and provisionalization with customized definitive abutments in the esthetic zone.

Materials and methods: Single unsalvageable maxillary anterior teeth were replaced with immediate implant placement and provisionalization with definitive abutments in 22 participants. Digital impressions and CBCT images were obtained presurgery, immediately after surgery, and 6 months after surgery. Horizontal and vertical buccal bone changes in thickness and height (HBBT, VBBH), vertical changes for the gingiva margin, mesial and distal papilla height, and horizontal changes for soft tissue (HCST) were analyzed using a 3D superimposition method.

Results: Twenty-two participants completed the study. No implant failed, and there were no mechanical or biologic complications for any patients. At 6 months after surgery, the mean HBBT changes at 0, 1, 2, 3, 5, 7, 10, 11.5, and 13 mm were -0.92 ± 0.73, -0.83 ± 0.53, -0.82 ± 0.49, -0.70 ± 0.64, -0.65 ± 0.47, -0.50 ± 0.51, -0.15 ± 0.45, -0.10 ± 0.57, and -0.00 ± 0.64 mm, respectively. The mean VBBH change was -0.61 ± 0.76 mm. The mean HCSTs at -3, -2, -1, 0, 1, 2, and 3 mm sub- and supra-implant shoulder were -0.65 ± 0.54, -0.70 ± 0.56, -0.65 ± 0.51, -0.61 ± 0.56, -0.47 ± 0.54, -0.47 ± 0.59, and -0.46 ± 0.59 mm, respectively. The mean gingiva margin recession was -0.38 ± 0.67 mm. The mean mesial papilla height recession was -0.03 ± 0.50 mm. The mean distal papilla height recession was -0.12 ± 0.56 mm.

Conclusion: The definitive abutment used with immediate implant placement and provisionalization could potentially maintain the buccal bone thickness and height. For the facial soft tissue, it also benefited the maintenance of the midfacial gingival margin position and papilla height during the 6-month follow-up. Int J Oral Maxillofac Implants 2023;38:479-488. doi: 10.11607/jomi.9914.

Purpose: To verify the survival rates and marginal bone loss (MBL) of implants in patients with different disability types.

Materials and methods: Clinical and radiographic assessments were performed in a total of 189 implants for fixed implant prostheses in 72 patients. Data were collected on loaded implants at least 1 year in function, and the mean observation time was 37.3 months. Implant survival was examined, and MBL was observed around the implants of two groups (mental disability vs physical disability) based on age, sex, implant location (anterior vs posterior), and prosthetic connection (internal vs external).

Results: Of the 189 implants, 4 failed; the total implant survival rate was 97.8% across a mean of 37.3 months. The cumulative survival rate at 85 months in a Kaplan-Meier survival curve analysis was 94.3% ± 3% in patients with mental disability and 50% ± 35.4% in patients with physical disability, which was a statistically significant difference between the disability groups (P = .006). Fisher exact test showed significant differences in MBL only with age (P < .001). The implant MBL by disability type-adjusted for age and observation period-showed significant differences in multiple linear regression analyses (P = .003).

Conclusion: The implant survival rates in patients with disability were in line with those reported for nondisabled patients. The MBL of the implants was within the physiologic bone loss after implant loading. Implants in patients with mental disability showed higher cumulative survival rates than in patients with physical disability, but also a higher amount of MBL. Within the limitations of this study, dental implants for patients with disability are viable. These results can establish future implant treatment plans for this population. Int J Oral Maxillofac Implants 2023;38:562-568. doi: 10.11607/jomi.9880.

Purpose: To determine whether immediate implant placement and loading renders different outcomes from delayed loading with respect to midfacial mucosal level in the maxillary esthetic area.

Materials and methods: A literature search was conducted in four electronic databases (PubMed, Web of Science, Embase, and Cochrane), identifying eligible clinical studies published prior to December 2021. Only randomized controlled trials (RCTs) comparing immediate implant placement with or without immediate loading in the maxillary esthetic zone with a mean follow-up of at least 12 months were selected for qualitative analysis and meta-analysis. The Cochrane Risk of Bias tool was adopted to assess the quality of the evidence. The heterogeneity between the pooled literature was analyzed through the chi-square test (P < .05) and quantified by the I2 index. A mixed-effects model was applied if it appeared that there was noteworthy heterogeneity; otherwise, a random-effects model was chosen. For continuous outcomes, the estimate of relative effect was presented to display the standardized mean differences (SMDs) and 95% CIs. For dichotomous variables, the Mantel-Haenszel statistical method was applied with effect sizes expressed as risk ratios (RRs) and 95% CIs. This study is registered on PROSPERO with number CRD42017078611.

Results: Out of 5,553 records, 8 RCTs were involved, providing data for 324 immediately placed implants (immediate implants subjected to immediate loading [IPIL]: 163; immediate implants subjected to delayed loading [IPDL]: 161) that had been in function within 12 to 60 months. Meta-analyses revealed significantly lower midfacial mucosal level changes for IPIL compared with IPDL, pointing to 0.48 mm (95% CI: -0.84 to -0.12; P = .01), as well as more significant papillary recession after IPDL (SMD -0.16; 95% CI: -0.31 to 0.00; P = .04). The differences regarding implant survival and marginal bone loss between the two loading groups showed no statistical significance. The result of metaanalyses revealed similar plaque score (SMD 0.03; 95% CI: -0.22 to 0.29; P = .79) and probing depth (SMD -0.09; 95% CI: -0.23 to 0.05; P = .21) for IPIL and IPDL. On the other hand, IPIL induced a trend toward more bleeding on probing (SMD 0.22; 95% CI: 0.01 to 0.42; P = .04) and less change in facial ridge dimension (SMD 0.94; 95% CI: -1.49 to -0.39; P < .01).

Conclusion: After a follow-up ranging from 12 to 60 months, midfacial mucosa level change was 0.48 mm lower following IPIL compared with IPDL. Immediate implant placement and loading is conducive to the preservation of physiologic soft and hard tissue architecture, appearing to offer considerable benefits in the anterior zone. In summary, IPIL should be considered in the esthetic zone if the primary implant stability permits. Int J Oral Maxillofac Implants 2023;38:422-434. do

Purpose: To compare the osseointegration process of the titanium dental implants with five different surface characteristics-sandblasted, sandblasted and acid-etched, hyaluronic acid-coated (HYA), hydroxyapatite-coated (HA), and machined-in an experimental sheep model at 1- and 3-month examinations.

Materials and methods: One hundred sixty dental implants were placed in the left and right tibias of 16 sheep. Five experimental groups were designed. Eight animals (80 implants) were used for biomechanical tests of reverse torque analysis and resonance frequency analysis (RFA). Eight of them (80 implants) were used for the evaluation of bone-to-implant contact (BIC) percentage in histomorphometric analysis. Forty of 80 implants (8 implants for each group) were used at 1-month examinations, and the remaining 40 (8 implants for each group) implants were used at 3-month examinations in the biomechanical test group and histomorphometric examination group, separately.

Results: Intergroup analysis at the 3-month followup showed that the increase in the implant stability quotient (ISQ) value was statistically significant for only the HYA group (P < .05). According to ISQ values at 1 and 3 months, group HYA showed statistically higher values at the 1 and 3-month examinations (P < .05). Groups HYA and HA had statistically higher reverse torque values than other groups at the 1-month examination (P < .05). At the 3-month evaluation, the HYA group showed significantly higher reverse torque values compared to other groups (P < .05). The BIC values of the sandblasted and acid-etched, HYA, and HA groups were significantly higher than the sandblasted and machined groups at the 1- and 3-month examinations (P < .05). The BIC value for the HA group showed decreased value at the 3-month examination compared to the 1-month examination (P < .05).

Conclusion: The RFA, reverse torque, and histomorphometric analysis at 1- and 3-month examinations show that dental implants coated with HYA may have increased potential for osseointegration compared to dental implants with sandblasted, sandblasted and acid-etched, machined, and HA-coated surfaces. Int J Oral Maxillofac Implants 2023;38:583-590. doi: 10.11607/jomi.9935.