Clinical parameters of implants placed bone level with cover screw or healing abutment techniques. 6 months post-surgery report from a randomized controlled clinical trial.

The objectives of this study were to identify risk factors associated with the premature cover screw exposure (pCSE) at dental implants and to evaluate the influence of a pCSE on peri-implant marginal bone level (MBL) change compared to non-exposed implants. Retrospective data assessment from 165 patients (mean age=54.0±14.4years) who received 395 submerged implants included demographic, health-related, and therapeutic variables which were analyzed for their respective impact. MBL change was detected at digital radiographs obtained from first- and second-stage surgeries. pCSE were detected in 43 patients (26.1%) and 53 implants (13.4%). An increased frequency of exposure was significantly associated with (I) male gender (p=0.012) at patient level and (II) the posterior region of the jaws (p=0.005), implant systems with platform-matching cover screws, and a vertical distance of ≥0.5mm between bone crest and the implant platform (both p<0.001) at implant level. The decrease in mesial, distal, and total MBL differed significantly (mean total=0.8±0.7 vs. 0.3±0.5; mean mesial=0.8±0.8 vs. 0.3±0.6; mean distal=0.8±0.8 vs. 0.3±0.6mm; p<0.001) between non-exposed and pCSE implants. Male patients, implants with platform-matched cover screws, or when placed supracrestally or in posterior sites revealed significantly more pCSE, resulting in significantly decreased peri-implant MBL compared with non-exposed implants. Patients with an enhanced risk of pCSE should follow frequent regular recalls during the healing period to enable for early diagnosis and intervention.

Tapered Screw Implants With Different Machined Neck Designs: A 3-Year Split-Mouth Randomized Controlled Prospective Study.

56th Annual Meeting of the American Academy of Implant Dentistry and the World Congress of Oral Implantology 7 Abstracts, 2007

Crestal Bone Level Around Tissue-Level Implants Restored with Platform Matching and Bone-Level Implants Restored with Platform Switching: A 5-Year Randomized Controlled Trial.

The focused question was: "In systemically healthy individuals with at least one two-piece dental implant, what is the efficacy of long (≥2 mm; intervention) compared with short (<2 mm; comparison) shoulder height abutments in peri-implant marginal bone level (MBL) changes at <1 year and ≥1 year reported by randomized controlled clinical trials?" An electronic and hand search was conducted to identify RCTs published up to August 2022. The primary outcome variable was changed in MBL from implant surgery to subsequent follow-ups. Mean values and standard deviations for each study were extracted. Weighted mean differences and 95% confidence intervals were calculated. Meta-analysis for MBL changes was performed through a random-effect restricted maximum-likelihood model at early (<1year) and late (≥1year) stages of bone remodeling. Publication bias and sensitivity tests were also applied. Subgroup analysis was performed to further explore possible sources of heterogeneity in the estimated treatment effect. Trial sequential analysis was performed to assess the required information and false-positive results. Six randomized clinical trials fulfilled the inclusion/exclusion criteria and were included in the qualitative and quantitative analysis with a follow-up range from 6 to 36 months after implant surgery. Meta-analysis revealed that long abutments significantly exhibited 0.27 mm (CI 95% -0.60, 0.06) and 0.33 mm (CI 05% -0.50, -0.16) lower MBL changes compared with short ones at <1year and≥1year, respectively. Subgroup meta-analysis revealed that studies with implants placed in a more subcrestal position significantly exhibited less differences in MBL changes between long and short abutments. No meta-analysis was conducted for peri-implant clinical parameters, and soft-tissue changes provided that reported data were scarce. Trial sequential analysis revealed insufficient information size to provide a definitive answer on the effect of abutment height in MBL. It might be cautiously concluded that two-piece implants with long abutments (≥2 mm) may display a protective role against marginal bone loss when compared with short ones (<2 mm) at <1year and ≥1year. A more subcrestal implant position seemed to minimize the effect of the abutment height in terms of MBL.

To evaluate whether changes in marginal bone level (MBL) around implants, in sites with different bone types, affect the over time implant stability measured by resonance frequency analysis (RFA). Seventy-eight implants were inserted into jawbones of 32 patients using a two-stage surgical protocol, and implant bone sites were grouped according to the Lekholm and Zarb bone classification. The implant stability quotient (ISQ) was measured by RFA at four time points: implant placement, uncovering, rehabilitation, and at 1-year follow-up after loading. The MBL was measured on periapical radiographs at uncovering and at 1-year follow-up. Percent change in bone level was calculated based on the difference between the implant length and height from the crestal bone level to the implant apex. Descriptive statistics, Pearson's correlation, and repeated-measures ANOVA were used for data analysis. Significant improvement of ISQ was found between implant insertion and uncovering surgery (P<0.001), while no significant changes were detected throughout the remaining follow-up period. The greatest improvement of ISQ was observed for bone type 4, compared with the other groups (P<0.001). Percent change in bone level had no effect on longitudinal measures of ISQ (P=0.337). The ISQ difference between uncovering and 1year after loading was not correlated with percent change in bone level (r=0.16; P=0.157). There was increased implant stability after implant placement, but it was not affected by changes in marginal bone level during the first year of loading.

A 3-Year Prospective Study on Radiographic Marginal Bone Evaluation Around Platform-Shifting Implants with Internal Conical Connections.

Immediately-loaded, narrow-diameter implants can be a less invasive alternative for the implant-supported fixed rehabilitation of narrow, posterior crests. To determine the stability and marginal bone level (MBL) changes of narrow-diameter, titanium-zirconium (TiZr) implants placed with flapless surgery and loaded immediately in the posterior region. Thirty-eight TiZr implants (3.3 mm diameter, 10 mm length, Roxolid, Straumann AG) were placed in the posterior crests of 14 patients with computer-guided flapless surgery as a support of 3-unit posterior bridges. Eighteen implants were loaded immediately, and 20 implants were loaded conventionally. The implant stability quotients were determined at the 1, 2, 4, and 8. weeks of healing before conventional loading, and at the 3, 6, and 12. months after loading by resonance frequency analysis. The MBL changes were measured by digital radiography. The surgical protocols were accomplished without any biological complications. There was no significant difference in the stability changes of TiZr implants between the loading groups (p > .05). The MBL changes were -0.18 ± 0.27 mm and -0.24 ± 0.27 mm at the 12. month of immediate and conventional loading, respectively, which was not statistically significant (p > .05). The stability and MBL changes of TiZr implants supporting posterior 3-unit bridges were clinically acceptable at the first year of loading.

The use of definitive abutments (DAs) at time of implant placement has been introduced to overcome limitations of dis/reconnection of healing/provisional abutments (PAs). With little and inconsistent information in the literature regarding the effectiveness of using DAs, the aim of this systematic review is to examine marginal bone and soft tissue level changes, technical and biologic complications, and implant failure rate associated with use of DAs and PAs. This systematic review was prepared according to guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and online trial registers were searched for studies comparing use of DAs and PAs. The Cochrane Collaboration risk of bias tool was used to assess selected studies, and meta-analyses were performed using statistical software. A total of 1,124 citations were identified. Of these, seven trials with 363 dental implants in 262 participants were included in the analysis. Pooled estimates for marginal bone level changes showed significant differences between the two prosthetic techniques in favor of using DAs. No significant differences were found in soft tissue level changes, technical and biologic complications, or implant failure rate. Within the limitations of this review, DAs appear to be a viable alternative to PAs at time of implant placement. However, favorable changes in peri-implant marginal bone level associated with use of DAs should be viewed with caution as its clinical significance is still uncertain.

Selective serotonin reuptake inhibitors (SSRIs) are used for the management of anxiety and depression. Existing evidence shows their negative impact on implant osseointegration, survival rates, and peri-implant health. Currently, there are limited data on their effect on peri-implant marginal bone levels. The primary goal of this retrospective study is to evaluate the association between SSRIs use and marginal bone level (MBL) changes around osseointegrated dental implants over time. Records from patients who received at least one dental implant between 2010 and 2021 were reviewed. Information related to medical history, SSRI use, and the implant site was obtained from patients' electronic charts. Mesial and distal MBLs were measured relative to the implant platform on digital intraoral radiographs, taken at the time of prosthesis installation and at the most recent follow-up visit. MBL changes were calculated. A total of 152 dental implants from 105 patients were included. The mean follow-up period was 46.97±21.87 months. The mean MBL change was significantly greater for SSRI users (0.41±0.76mm) compared to non-users (0.04±0.65mm) [MD=0.37mm, p=0.00, 95% CI: (-0.61)-(-0.15mm)]. Mesial MBL change of 0.42±0.84mm and 0.02±0.71mm was noted for SSRI users and non-users, respectively. The distal MBL change was 0.4±0.93mm and 0.07±0.73mm, respectively. Smoking, sex, and implant location did not seem to influence the MBL differences between groups. Use of SSRIs is associated with greater marginal bone loss around osseointegrated dental implants in function for a mean period of 3.8 years.

The purpose of this study was to evaluate the current evidence on marginal bone-level changes (ΔMBL) around internal connection implants with fixed prostheses by jaw location over time. An electronic literature search for ΔMBL (change in marginal bone level) was conducted in 6 databases. The data from the included manuscripts were categorized by jaw sextant of the implants and duration of follow-up (<2 years, 2-5 years, and >5 years). Meta-analyses were performed on groups with at least 5 studies. A total of 1270 records were screened. Full-text review of 413 papers resulted in a total of 46 studies (representing 2259 patients with 4970 implants) included for quantitative synthesis and analysis. The ΔMBL was summarized at 2 time intervals with the following results: <2 years (anterior maxilla = 0.393 mm [95% confidence interval {CI}, 0.172, 0.613], posterior maxilla = 0.468 mm [95% CI, 0.288, 0.648], and posterior mandible 0.559 mm [95% CI, 0.397, 0.72]), 2 to 5 years (anterior maxilla = 0.683 mm [95% CI, 0.224, 1.142], posterior maxilla = 0.645 mm [95% CI, 0.42, 0.87], and posterior mandible 0.563 mm [95% CI, 0.278, 0.849]). There were insufficient studies in the anterior mandible and with follow-up data over 5 years for quantitative synthesis. Within the limitations of this study, location within the maxillary and mandibular jaws does not seem to influence ΔMBL around internal connection bone level implants with fixed restorations. Although there may be a tendency for greater initial remodeling in the posterior mandible followed by long-term stability, additional studies are needed to evaluate this further.

To conduct a systematic review on the clinical outcome of single implant-supported two-unit cantilever FDP's and to conduct a 5-year prospective comparative pilot study of patients with a missing central and lateral upper incisor treated with either a single implant-supported two-unit cantilever FDP or two implants with solitary implant crowns in the aesthetic zone. Medline, Embase and the Cochrane Central Register of Controlled Trials were searched (last search 1 August 2016) for eligible studies. In the comparative pilot study, an implant-cantilever group of five patients with a single implant-supported two-unit cantilever FDP (NobelReplace Groovy Regular Platform) was compared with an implant-implant group of five patients with two adjacent single implant-supported crowns (NobelReplace Groovy Regular Platform) in the aesthetic zone. Implant survival, marginal bone level (MBL) changes, pocket probing depth, papilla index and patient satisfaction were assessed during a 5-year follow-up period. Five of 276 articles were considered eligible for data extraction. Implant survival ranged from 96·6% to 100%. Marginal bone level changes were higher in the anterior region than in the posterior region. Technical complications occurred more often in the posterior than anterior region. In the 5-year comparative pilot study, no clinically significant differences in hard and soft peri-implant tissue levels occurred between both groups. Single implant-supported two-unit cantilever FDP's can be a viable alternative to the placement of two adjacent single implant crowns in the aesthetic zone. Due to technical complications, placement of two-unit cantilever crowns in the posterior region can be considered unwise.

Background Using a pair of different low-profile abutments to assist mandibular implant overdenture (MIOD) in limited restorative space is questionable due to the different morphology. Objective To investigate the marginal bone level (MBL) change and peri-implant-tissue health (PITH) around a pair of OT Equator® and Locator® suprastructures assisting MIOD. Methods Seventeen edentulous patients received MIOD assisted by OT Equator® and Locator®. MBL change was investigated at the implant loading (T1), after six months (T2) and twelve months (T3) of implant loading. PITH was evaluated at T2 and T3. Results There was within abutment significant difference in MBL change after T2 and T3 of loading for Locator (0.05 ± 0.02 and 0.32 ± 0.08, respectively) (P=0.01); and for Equator (0.11 ± 0.08 and 0.21 ± 0.09, respectively) (P=0.01). Also, there was a significant difference between Locator and Equator on the modified plaque index (MPI) after T3 (P=0.01). The significant results were recorded for the MPI at T2 and T3 for Locator (0.92 ± 0.26 and 1.5 ± 0.51, respectively) (P=0.01) and for Equator (0.82 ± 0.26 and 1.42 ± 0.51, respectively) (P=0.003). For modified bleeding index, there was significant difference at T2 and T3 for Locator (0.57 ± 0.19 and 1.14 ± 0.41, respectively) (P=0.03) and for Equator (0.46 ± 0.22 and 1.07 ± 0.41, respectively) (P=0.01). For gingival index, there was significant difference at T2 and T3 for Locator (0.57 ± 0.11 and 1.28 ± 0.35, respectively) (P=0.001) and for Equator (0.35 ± 0.21 and 1.1 ± 0.46, respectively) (P=0.001). Conclusions Using different pairs of the low-profile OT Equator® and Locator® abutments to assist MIOD is clinically acceptable based on the MBL change and PITH outcomes.

Implant-Abutment Connections and Their Effect on Implant Survival Rates and Changes in Marginal Bone Levels (Δ): A Systematic Review and Meta-Analysis of 45,347 Oral Implants.

PurposeIncreasing scientific evidence support extending the application of short dental implants to non-atrophic dental arches. The purpose of this study has been the evaluation of extra-short implants (≤ 6.5 mm in length) that were placed in atrophic and non-atrophic anatomical sites to support the same prosthesis.MethodsFor that, a retrospective study was conducted by including complete dentures that were solely supported by extra-short implants in the maxilla and/or the mandible. Clinical data about patients, implants, anatomy, and prosthesis were obtained. Statistical analysis was performed to assess implant- and prosthesis-survival, changes in the marginal bone level and prosthetic complications.ResultsA total of 87 implants in 15 screw-retained complete dentures were assessed. None of the prostheses nor the extra-short implant failed during the follow-up of 27.2 ± 15.4 months. The changes in the mesial and distal marginal bone level were + 0.15 ± 0.51 mm and + 0.11 ± 0.50 mm, respectively. Comparing the implants according to the availability of sufficient bone to place longer implants, indicated the absence of significant differences in the changes of the mesial marginal bone level. However, the changes in the distal marginal bone level showed a statistically significant difference in favor of implants that were placed in non-atrophic sites. Two events of screw loosening were reported that were resolved by retightening the screws.ConclusionsImplant- and prosthesis-related outcomes support the use of extra-short implants in atrophic and non-atrophic site to support complete prosthesis.Graphical