Clinical and radiographic outcomes of implant-supported fixed prostheses with cantilever extension in anterior mandible: A retrospective study.

OBJECTIVES: The objective of this study is to analyze the clinical and radiographic outcomes of implant-supported fixed protheses with cantilever extensions (ISFPCs) in the partially edentulous anterior mandible. MATERIALS AND METHODS: Patients who received anterior mandible implant restoration between January 2016 and December 2021 were included. Patients with two, three, or four continuous missing teeth receiving adjacent implant supported single-unit crowns (ISSCs), ISFPCs, implant-supported fixed protheses without cantilever extensions (ISFPNs) were divided into groups: ISSC+ISSC, ISFPC, ISSC+ISFPC, three-unit ISFPN, ISFPC+ISFPC, or four-unit ISFPN, respectively. We recorded and evaluated survival rates, mechanical and biological complications, peri-implant marginal bone loss (MBL), esthetic outcomes, and patient perceptions. Statistical analysis was performed using linear mixed models (LMM). RESULTS: The study included 87 patients and 152 implants. No implant loss occurred during an average follow-up of 3.48 ± 1.85 years (range: 1-7 years). According to LMM models, prosthetic type had a statistically significant impact on MBL during follow-up periods, in favor of the ISFPC and ISFPC+ISFPC groups (0.16 ± 0.48 mm vs. 0.51 ± 0.49 mm, p = .034; 0.22 ± 0.49 mm vs. 0.60 ± 0.62 mm, p = .043, respectively). Mechanical and biological complications were relatively low and comparable. The four-unit ISFPC group had higher subjective esthetic scores compared with the ISSC+ISSC group (98.6 vs. 83.8, p < .05), and patients in the ISFPC+ISFPC group expressed greater satisfaction with cleanability than the ISFPN group (98.8 vs. 80.6). CONCLUSION: ISFPCs offer a highly predictable treatment option in the anterior mandible, characterized by high survival rates, and comparable complication rates, peri-implant bone stability and esthetics to adjacent ISSCs or ISFPNs.

Four-mm-short implants in the rehabilitation of posterior atrophic jaws: A retrospective study on 212 patients with a mean follow-up of 8.02 years.

OBJECTIVE: This study aimed to assess clinical efficacy of 4-mm-short implants in patients with posterior severe vertical bone atrophy in the medium- and long-term follow-up. MATERIALS AND METHODS: Patients rehabilitated with 4-mm-short implants in the posterior atrophic jaws, with a minimum follow-up of 3 years post-loading, were included in the study. Data were collected for eligible patients, and marginal bone loss (MBL) for each implant was evaluated. The research outcomes were implant failure, MBL and complications. RESULTS: A total of 212 patients with 496 implants were included, resulting in a mean follow-up of 8.02 ± 2.17 years. The implant survival rate was 95.36% (95% CI: 93.12%-97.04%). More implant failures were observed in the maxilla (p = .02) and fewer failures were observed in patients undergoing more number of hygienic sessions per year (p < .001). The average MBL after 1-year-loading was 0.47 mm, increasing to 0.59 mm after 10 years; after 3 years no statistically significant increase in MBL was observed. Maxillary implants showed greater bone loss than mandibular ones (p < .001). More frequent professional oral hygiene sessions per year resulted being related with reduced MBL (p < .001). CONCLUSIONS: Four-mm-short implants showed high survival rates with an up to 10-year follow-up. Their use can offer a fixed prosthetic solution for patients with posterior vertical bone atrophy, minimizing surgical invasiveness, rehabilitative times and costs.

Marginal changes at bone-level implants supporting dental prostheses with or without intermediate standardised abutments after 36 months: Randomised controlled clinical trial.

OBJECTIVE: The objective of this study is to evaluate the changes at marginal bone level at implants restored with screw-retained prosthesis connected directly to the implants or with an intermediate abutment, after 3-year follow-up. MATERIAL AND METHODS: Thirty-six partially edentulous patients received 72 implants. Each patient received 2 implants and a 2-4-unit screw-retained implant-prosthesis. The test group implants received a screw-retained prosthesis connected directly to the implant shoulder, the control group prosthesis were connected through a 3-mm standardised intermediate abutment. Clinical and radiological data were recorded at baseline and at 6-, 12-, and 36-month follow-up. RESULTS: At 36 months, the mean marginal bone loss was 0.13 ± 0.18 mm for the control group and 0.20 ± 0.24 for the test group, with no significant differences between groups (p > .05). Clinical variables (Probing Pocket Depth, Bleeding on Probing and Plaque Index) at 36 months also showed no significant difference between groups. Minor complications frequency was 6.7% in the control group and 5.3% in test group. None of the groups suffered from mayor complications. Patient Reported Outcomes (PROs) showed a General Satisfaction mean score in the control group of 9.40 (SD 0.82) and 9.37 (SD 1.06) in the test group with no significant differences between groups. CONCLUSIONS: Bone-level implants restored with screw-retained partial prostheses with or without intermediate abutments showed similar radiographic and clinical outcomes after 3 years.

Radiographic evaluation of marginal bone levels around implants supporting splinted fixed bridges: A retrospective study on 412 implants.

OBJECTIVES: The effect of the implant position within the prosthesis on bone remodeling is scarcely documented so far. Thus, the aim of the present study was to investigate whether central implants may suffer higher peri-implant marginal bone levels (MBL) compared to laterals in case of fixed splinted bridges supported by ≥ three implants. MATERIALS AND METHODS: Partially edentulous subjects rehabilitated with at least one fixed bridge supported by ≥ three dental implants were enrolled. MBL was assessed radiographically by means of intraoral radiographs acquired with phosphor plates and imported in a dedicated software. MBL was calculated as the distance between the implant platform level and the most coronal visible bone-to-implant contact. A three-level linear mixed effects model was used for investigating the fixed effect of patient-, prosthesis-, and implant-level variables on the MBL. RESULTS: Overall, 90 patients rehabilitated with 130 splinted fixed bridges supported by 412 implants were included. The median follow-up was 136 months. The mean peri-implant MBL resulted statistically significantly higher at central implants if compared to lateral implants (p < .01). The estimated MBL averages for central and external implants were 1.68 and 1.18 mm, respectively. The prosthesis-level variables suggested that a cement-retained bridge was prone to a significant 0.82 mm higher MBL than a screw-retained one. Implant surface showed an association with MBL changes, although less pronounced than implant retention. CONCLUSIONS: In case of ≥3 adjacent implants supporting splinted bridges, central implants were more predisposed to MBL compared to laterals. At the prosthesis level, implants supporting cement-retained bridges were statistically more susceptible to MBL compared to screw-retained ones. Surface characteristics can also influence MBL stability at the implant level.

Restoration of posterior teeth by narrow diameter implants in hyperglycemic and normoglycemic patients - 4-year results of a case-control study.

OBJECTIVES: To investigate the four-year clinical outcome and marginal bone loss around narrow-diameter implants in patients with uncontrolled diabetes mellitus type 2 (T2DM) and normo-glycemic individuals. MATERIALS AND METHODS: In 11 T2DM patients with a concentration of glycated hemoglobin (HbA1C) > 6.5% (test group) and 15 normoglycemic patients (HbA1C < 6.0%; control group), one narrow-diameter tissue level implant, placed in the posterior maxilla or mandible, was investigated. The clinical parameters probing depth (PD), bleeding on probing (BOP), attachment loss (CAL), recession, and papilla bleeding index (PBI) were assessed manually after 24 and 48 months of function. The paired digital periapical radiographs were analyzed regarding the change in marginal bone level (MBL) from baseline to 48 months post-op. The technical complications were recorded. RESULTS: In the T2DM group, 11 patients were available for follow-ups. The overall implant survival rate after 48 months was 100%. The differences in means for the clinical parameters and the MBL between the T2DM and normo-glycemic patients for the observation period were statistically non-significant. No technical complications were recorded. CONCLUSIONS: The study demonstrated an encouraging clinical outcome with ND implants in patients with uncontrolled T2DM compared to non-diabetics after 48 months' post loading. CLINICAL RELEVANCE: Patients with HbA1C > 6.5% may benefit from the treatment with narrow-diameter implants by avoiding complex surgical interventions with augmentation procedures. REGISTRATION NUMBER (CLINICALTRIALS.GOV): NCT04630691.

Effect of vertical implant position on marginal bone loss: a randomized clinical trial.

OBJECTIVES: One of the most important factors that has influence on dental implants success rate is marginal bone loss. The purpose of this study is to investigate the effect of the implant's vertical position and the soft tissue's thickness on the rate of marginal bone loss of the dental implant. MATERIALS AND METHODS: In this single-blind randomized clinical trial study, 56 implants placed in the posterior region of mandible of 33 patients (19 women, 14 men) were divided into two groups. The group of crestal (28 implants) and subcrestal (28 implants) implants, each group was divided into two sub-groups with soft tissue thickness of 2 mm and less than 2 mm (14 implants) and more than 2 mm (14 implants). The amount of marginal bone loss was measured by Scanora 5.2 program with radiographs Digital parallelism based on the effect of the vertical position of the implant, soft tissue thickness, three months after placement, and three months after loading implants (six months after implant placement). RESULTS: The results showed that marginal bone loss in subcrestal implants is significantly more than crestal implants (p-value = 0.001), and also marginal bone loss in the soft tissue thickness group of 2 mm and less is significantly more than the group of soft tissue thickness more than 2 mm (p-value < 0.001). The amount of marginal bone loss three months after implant loading was significantly higher than three months after implant placement (p-value < 0.001). CONCLUSION: The implant's vertical position and the soft tissue's thickness around the implant are effective factors in the amount of marginal bone loss. Marginal bone loss is more in subcrestal implants and in cases with less soft tissue thickness. The time factor significantly affects the amount of marginal bone loss. TRIAL REGISTRATION: this clinical trial was registered at Iranian Registry of Clinical Trials, registration number IRCT20120215009014N415, registration date 20,220,110, (https//en.irct.ir/trial/60,991).

Clinical assessment of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. A randomized controlled clinical trial.

OBJECTIVES: To evaluate the peri-implant marginal bone loss (MBL) and prosthodontic complications of maxillary screw-retained implant prosthesis fabricated from digital versus conventional full- arch implant impression. MATERIAL AND METHODS: 28 participants with edentulous maxillary arches were randomly selected and enrolled in two equal groups; Group I conventional impression group (CIG) and Group II Digital impression group (DIG). All patients were rehabilitated with maxillary screwretained implant prosthesis retained by 6 implants. Peri-implant MBL and prosthodontic complications and were registered at 6, 12, and 24 months (m). Data was collected and statistically analyzed. RESULTS: Regarding the effect of time, there was a statistically significant increase in MBL at 6, 12 and 24 m follow-up periods (P<.001). As for the effect of groups, there was no statistically significant difference in MBL between CIG and DIG at 6, 12 and 24 m where P value was 0.083, 0.087 and 0.133 respectively. Prosthetic complications were recorded 19 times in the conventional group and 12 times in the digital group with no significant difference between both groups (P=.303). CONCLUSION: Digital full -arch implant impression is a reliable impression technique and may represent an alternative to conventional impression technique in the fabrication of maxillary screw-retained implant prosthesis.

Implant survival rate and marginal bone loss of 174 implants with different variables associated over a minimum observational period of 20 years: A retrospective study.

PURPOSE: To investigate the long-term implant survival rate and marginal bone loss (MBL) of implants with different variables associated over an observational period of at least 20 years. MATERIALS AND METHODS: Patients with at least one implant placed prior to 2001 were recalled and visited. Data on implant macro-design, prosthetic aspects, site distribution, and patient-related factors were collected. MBL was evaluated on intraoral X-rays and peri-implant soft tissue parameters were recorded. The patients were asked to fill out a questionnaire to evaluate their satisfaction with the treatment received. Descriptive statistics indicators were estimated. Analysis of variance and analysis of covariance models were used to investigate any differences in the MBL and peri-implant probing depth (PPD) among the variables. A chi-square analysis was performed to investigate any association between different types of prosthetic implant-supported rehabilitations and survival/success outcomes. RESULTS: Forty-one (41) patients and 174 implants were included with a mean observational period of 23.3 ± 2.8 years. The implant survival and success rates were 96.5% and 83.3% respectively, while 3.5% of early failures were detected. The lowest success rates were observed for implants supporting fixed full-arch rehabilitations (71.05%) and overdenture rehabilitations (86.11%). A mean MBL of 1.81 ± 0.71 mm and a mean PPD of 3.38 ± 1.62 mm were recorded. The interaction between the collected data with MBL and PPD did not reveal any statistically significant differences between the variables (p > 0.05). A statistically significant difference was recorded when analyzing the association between the different types of prosthetic implant-supported rehabilitations and success rates (p = 0.014), with fixed and removable full-arch rehabilitations presenting with lower success rates. Answers to the questionnaire showed a generally high level of satisfaction. CONCLUSIONS: Within the limits of this retrospective study and based on the results, an implant survival rate higher than 96% was observed after a mean observational period of 23.3 ± 2.8 years. Both the implant survival rate and MBL seemed stable after a mean observational period of 23.3 ± 2.8 years. Implants supporting fixed and removable full-arch rehabilitations seemed to present lower success rates over time. Implant rehabilitation seemed to provide patients with optimal long-term outcomes in terms of functional and psychological aspects.

DIGITAL SCANS, COMPARED TO CONVENTIONAL IMPRESSIONS, MAY EXPEDITE FABRICATION TIME FOR FULL-ARCH IMPLANT-SUPPORTED PROSTHESES WHILE MAINTAINING A COMPARABLE LEVEL OF MARGINAL BONE LOSS.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Clinical outcomes of digital scans versus conventional impressions for implant-supported fixed complete arch prostheses: A systematic review and meta-analysis. I. A., Spin-Neto, R., Sesma, N., & da Silva, E. V. F. The Journal of Prosthetic Dentistry (2023). SOURCE OF FUNDING: Not reported. TYPE OF STUDY/DESIGN: Systematic review with network meta-analysis of data.

Less marginal bone loss around bone-level implants restored with long abutments: A systematic review and meta-analysis.

The aim of this study was to investigate the biological outcomes of bone-level implants restored with long vs. short abutments, with regard to the 'one abutment at one time' protocol. The systematic search was performed in five databases: MEDLINE (PubMed), EMBASE, Web of Science, Scopus, and CENTRAL for randomized controlled trials up to January 14, 2023. Data were collected for marginal bone loss, bleeding on probing, and probing pocket depth by two reviewers. As effect size measure, mean difference (MD), and risk ratio (RR) were used for continuous and categorical outcomes, R-statistics software was used for conducting statistical analyses. For quality and certainty assessment, Risk of Bias Tool 2, ROBINS-I, and GRADE approach were used. The search resulted in 4055 records without any duplicates. After title, abstract, and full-text analysis, eight articles were found eligible for inclusion. Bone-level and platform-switched implants presented less marginal bone loss after 6 months and 1 year as well, when long abutments were used (MD 0.63, 95% CI: [-0.16; 1.42]) and (MD 0.26, 95% CI: [-0.02; 0.53]). However, subgroup analysis revealed no difference in marginal bone loss when applying 'one abutment at one time' protocol (p = 0.973). Bleeding on probing and probing pocket depth presented similarly good results in both groups without almost any differences (RR 0.97, 95% CI: [0.76; 1.23]) and (MD -0.05, 95% CI: [-1.11; 1.01]). Longer abutments on bone-level implants seem to be a favorable choice for decreasing early marginal bone loss, irrespective of connection timing.

Can radiomic features extracted from intra-oral radiographs predict physiological bone remodelling around dental implants? A hypothesis-generating study.

AIM: The rate of physiological bone remodelling (PBR) occurring after implant placement has been associated with the later onset of progressive bone loss and peri-implantitis, leading to medium- and long-term implant therapy failure. It is still questionable, however, whether PBR is associated with specific bone characteristics. The aim of this study was to assess whether radiomic analysis could reveal not readily appreciable bone features useful for the prediction of PBR. MATERIALS AND METHODS: Radiomic features were extracted from the radiographs taken at implant placement (T0) using LifeX software. Because of the multi-centre design of the source study, ComBat harmonization was applied to the cohort. Different machine-learning models were trained on selected radiomic features to develop and internally validate algorithms capable of predicting high PBR. In addition, results of the algorithm were included in a multivariate analysis with other clinical variables (tissue thickness and depth of implant position) to test their independent correlation with PBR. RESULTS: Specific radiomic features extracted at T0 are associated with higher PBR around tissue-level implants after 3 months of unsubmerged healing (T1). In addition, taking advantage of machine-learning methods, a naive Bayes model was trained using radiomic features selected by fast correlation-based filter (FCBF), which showed the best performance in the prediction of PBR (AUC = 0.751, sensitivity = 66.0%, specificity = 68.4%, positive predictive value = 73.3%, negative predictive value = 60.5%). In addition, results of the whole model were included in a multivariate analysis with tissue thickness and depth of implant position, which were still found to be independently associated with PBR (p-value < .01). CONCLUSION: The combination of radiomics and machine-learning methods seems to be a promising approach for the early prediction of PBR. Such an innovative approach could be also used for the study of not readily disclosed bone characteristics, thus helping to explain not fully understood clinical phenomena. Although promising, the performance of the radiomic model should be improved in terms of specificity and sensitivity by further studies in this field.

Influence of abutment shape on peri-implant tissue conditions: A randomized clinical trial.

OBJECTIVE: To analyze the influence of 3-mm high abutments with different shapes (cylindrical abutment vs. wide abutment) on marginal bone-level changes (bone loss and bone remodeling). The influence of abutment shape on implant success, probing pocket depth (PPD), and bleeding on probing (BoP) was studied as secondary objectives. MATERIALS AND METHODS: Patients with a partially edentulous area requiring fixed dental prostheses by two implants in the posterior mandible or maxilla were included. The implants were 1 mm subcrestally placed, and osseointegration healing was submerged. Three-mm high abutments with two different shapes were randomly placed in second-stage surgery: cylindrical abutments (cylindrical group) and wide abutments (wide group). Marginal bone-level changes were measured using parallelized periapical radiographs at abutment placement, at definitive prosthesis placement, and at 1, 3, 6, and 12 months after loading. PPD and BoP were likewise measured at the control visits. RESULTS: Sixty-four dental implants in 25 patients were included. Statistically significant differences were found in bone-level changes. The cylindrical group exhibited less mean marginal bone remodeling (MBR) and marginal bone loss (MBL) than the wide group (p < .05). Moreover, the cylindrical group showed significantly less BoP (p < .05). CONCLUSION: Abutment shape had a significant influence upon marginal bone-level changes during the first 12 months. Cylindrical abutments caused less MBR and MBL than wide abutments. More clinical studies involving longer follow-ups and analyzing other abutment modifications are needed to improve our understanding of how abutments can affect peri-implant tissue stability.

Influence of the abutment height on marginal bone level changes around two-piece dental implants: Meta-analysis and trial sequential analysis of randomized clinical trials.

BACKGROUND: 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?" MATERIALS AND METHODS: 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 (<1 year) and late (≥1 year) 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. 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 <1 year and ≥1 year, 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. CONCLUSIONS: 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 <1 year and ≥1 year. A more subcrestal implant position seemed to minimize the effect of the abutment height in terms of MBL.

Influence of soft tissue thickness on marginal bone level around dental implants: A systematic review with meta-analysis and trial-sequential analysis.

OBJECTIVES: The aim of the present review and meta-analysis was to evaluate the influence of soft tissue thickness on initial bone remodeling after implant installation. MATERIALS AND METHODS: A literature search was conducted by two independent reviewers on electronic databases up to May 2022. Randomized controlled trials (RCTs) and controlled clinical trials (CCTs) performed on human subjects were included. The risk of bias was evaluated using Cochrane Collaboration's tool. Meta-analysis and Trial Sequential Analysis (TSA) were performed on the selected articles. The primary outcome was marginal bone loss. RESULTS: After screening, 6 studies were included in the final analysis, with a total of 354 implants, and a follow-up from 10 to 14 months. 194 implants were placed in a ≥ 2 mm soft tissue thickness, while 160 had <2 mm soft tissue thickness before implant placement. The included studies had a high level of heterogeneity (I2  > 50%). The meta-analysis indicated a statistically significant difference between the two groups (0.54; p = .027) and the TSA analysis confirmed the results, despite the limited number of dental implants. Additional analysis showed that age and follow-up parameters were not statistically significant factors influencing the bone loss (p = .22 and p = .16, respectively). CONCLUSIONS: Based on the available RCTS and CCTs, initial soft tissue thickness seems to influence marginal bone loss after a short follow-up period. Based on TSA analysis, further studies are needed to assess the influence of the soft tissue thickness on marginal bone loss. PROSPERO registration number: CRD42021235324.

Clinical outcomes of full-arch immediate fixed prostheses supported by two axial and two tilted implants: A retrospective cohort study with 12-15 years of follow-up.

PURPOSE: To retrospectively assess clinical and radiographic outcomes of immediately loaded full-arch fixed prostheses supported by axial and tilted implants up to 15 years of function. MATERIALS AND METHODS: Patients with one completely edentulous arch received an immediate full-arch fixed prosthesis supported by two anterior axial and two posterior tilted implants. Definitive prosthesis consisting of a CAD-CAM titanium framework and acrylic teeth was delivered 6 months later. Patients were regularly followed to assess clinical parameters and marginal bone level (MBL) change. Multilevel regression analysis was performed to investigate factors affecting implant failure and MBL. RESULTS: Six hundred ninety-two implants were placed in 72 maxillae and 101 mandibles. Seven maxillary implants (5 axial and 2 tilted) in 6 patients and 12 mandibular implants (6 axial and 6 tilted) in 5 patients failed. 15-year cumulative implant survival was 97.51% and 96.91% in maxilla and mandible, respectively (p = .64). After 10 years, the difference in MBL between axial and tilted implants was not significant in the maxilla (p = .47, 65 patients), while it was in the mandible (p < .001, 80 patients). Significant higher bone loss was reported in the mandible at both 5- and 10-year follow-up (p < .001 and p = .004, respectively). Mixed-effect multilevel linear regression evidenced a correlation between arch and bone loss at 5- and 10-year follow-up, while no correlation was found with age, gender, smoking, diabetes, and history of periodontal disease. CONCLUSION: This long-term study suggests that the present technique can be considered a viable treatment modality for the immediate rehabilitation of both maxilla and mandible.

Marginal changes at bone-level implants supporting fixed screw-retained partial implant prostheses with or without intermediate standardised abutments: 1-year results of a randomised controlled clinical trial.

OBJECTIVE: To compare marginal changes at bone-level implants restored with screw-retained implant prosthesis with or without intermediate standardised abutments, after 1 year of follow-up. MATERIALS AND METHODS: Thirty-six partially edentulous patients received 72 implants. Each patient received 2 implants and a 2- to 4-unit screw-retained implant-prosthesis. The test group received implants consisting of a screw-retained prosthesis connected directly to the implant shoulder, while the prostheses in the control group were connected through a 3-mm standardised intermediate abutment. Clinical and radiological data were recorded at baseline and at 3, 6 and 12 months in follow-up visits. RESULTS: At 12 months, the marginal bone loss was 0.17 ± 0.24 mm for the test group (19 patients) and 0.09 ± 0.15 mm for the control group (17 patients), with no statistically significant differences (p > .05). The mean probing pocket depth was 2.96 mm ± 0.46 for the test group and 2.86 ± 0.62 mm for the control group. The test and control groups showed bleeding on probing levels of 18.86 ± 14.12% and 13.73 ± 17.66%, respectively. All patients scored below 25% on the plaque index levels. CONCLUSIONS: Restoration of bone-level implants with fixed screw-retained partial prostheses with or without intermediate abutments presented similar radiographic and clinical outcomes after 1 year.

Clinical and radiographic outcomes of zirconia dental implants-A systematic review and meta-analysis.

OBJECTIVES: For the present review, the following focused question was addressed: In patients with root-analog dental implants, what is the effect of implants made of other materials than titanium (alloy) on implant survival, marginal bone loss (MBL), and technical and biological complications after at least 5 years. MATERIALS AND METHODS: An electronic (Medline, Embase, Web of Science) search was performed to identify observational clinical studies published from January 2000 investigating a minimum of 20 commercially available zirconia implants with a mean follow-up of at least 60 months. Primary outcome was implant survival, secondary outcomes included peri-implant MBL, probing depths (PDs), and technical and biological complications. Meta-analyses were performed to evaluate implant survival, MBL, and PD. RESULTS: From 5129 titles, 580 abstracts were selected, and 111 full-text articles were screened. Finally, 4 prospective and 2 retrospective observational clinical cohort studies were included for data extraction. Meta-analyses estimated after 5 years of loading mean values of 97.2% (95% CI 94.7-99.1) for survival (277 implants, 221 patients), 1.1 mm (95% CI: 0.9-1.3) for MBL (229 implants, 173 patients), and 3.0 mm (95% CI 2.5-3.4) for PDs (231 implants, 175 patients). CONCLUSIONS: After 5 years, commercially available zirconia implants showed reliable clinical performance based on survival rates, MBL, and PD values. However, more well-designed prospective clinical studies and randomized clinical trials investigating titanium and zirconia implants are needed to confirm the presently evaluated promising outcomes.

Survival and success of zirconia compared with titanium implants: a systematic review and meta-analysis.

OBJECTIVE: This systematic review assessed the available evidence on the survival and success rate of zirconia and titanium implants. As secondary outcomes, aesthetic, radiographic and clinical parameters, as well as biological and mechanical complications, were considered. MATERIALS AND METHODS: A systematic search was performed up to March 2022 to identify CCTs/RCTs comparing zirconia and titanium implants with a minimum of 12 months of follow-up. Meta-analysis was performed when ≥ 2 articles with similar characteristics were retrieved. RESULTS: Four published articles with two RCTs (2 different patient populations) with 100 zirconia and 99 titanium implants that were followed up over 12-80 months were selected out of the 6040 articles. A non-statistically significant difference between zirconia and titanium implant survival at 12 months was suggested (P = 0.0938). The success rates were 57.5-93.3% and 57.1-100% for zirconia and titanium implants, respectively. The pink aesthetic score (PES) was higher for zirconia (10.33 ± 2.06 to 11.38 ± 0.92) compared to titanium implants (8.14 ± 3.58 to 11.56 ± 1.0). CONCLUSION: Based on the 2 RCTs retrieved in the literature, similar survival rates were reported for zirconia and titanium implants in the short term (12 months of follow-up). Future RCTs are warranted to evaluate the long-term outcomes of zirconia implants. CLINICAL RELEVANCE: Zirconia implants may be the procedure of choice, particularly in the aesthetic zone, since they show a similar survival and success rate as titanium implants on a short-term follow-up. TRIAL REGISTRATION: Systematic review registration number-CRD42021288704 (PROSPERO).

Influence of different mucosal phenotype on early and long-term marginal bone loss around implants: a systematic review and meta-analysis.

OBJECTIVES: To investigate the influence of different mucosal phenotypes on peri-implant marginal bone loss. MATERIALS AND METHODS: The search was conducted in five databases including PubMed, Embase, Cochrane, Scopus, and Web of Science (until 1st Sept. 2022) to identify relevant clinical studies. Potentially relevant journals were also manually searched. Two reviewers independently screened studies, extracted data, and evaluated the quality of the studies. Prospective clinical trials and observational studies investigating peri-implant marginal bone loss in thick-mucosa and thin-mucosa groups were included. RESULTS: A total of 14 studies were included in this systematic review. Results of the meta-analysis revealed a weighted mean difference of 0.38 mm for marginal bone loss between thick- and thin-mucosa groups (95% confidence interval = 0.02-0.74, P = 0.002). Statistical significance existed in short-term (follow-up ≤ 1 year) data (WMD = 0.41 mm, 95%CI = 0.11-0.70, P = 0.007), but not in long term (follow-up ≥ 3 y) data (WMD = 0.17 mm, 95%CI = - 0.02-0.36, P = 0.07). Survival rate revealed no difference between thick and thin mucosa groups. In subgroup analyses, a positive association between thick mucosa and less marginal bone loss was found in the non-submerged group, cement-retained group, and bone-level group. CONCLUSIONS: A significantly less marginal bone loss occurred in implants with thick mucosa than with thin mucosa in the short term, whereas no significant difference was observed in the long term. Due to the substantial heterogeneity and limited long-term data, further high-quality evidence is warranted to confirm the results. CLINICAL RELEVANCE: Clinicians are advised to use caution in treating patients with thin mucosa and adhere closely to indications and protocols to minimize marginal bone loss.

Marginal bone loss around dental implants: comparison between diabetic and non-diabetic patients-a retrospective clinical study.

OBJECTIVES: The aim of the present retrospective study was to compare the marginal bone loss (MBL) around dental implants in a group of diabetic patients in relation to a matched group of non-diabetic patients. MATERIALS AND METHODS: The present dental record-based retrospective study included patients selected from individuals treated with dental implants at one specialist clinic in Malmö, Sweden. Patients were excluded if they had history of periodontitis and/or were treated for periodontal disease. The study group included 710 implants installed in 180 patients (mean age 60.3±13.0 years), 349 implants in 90 diabetic (21 T1DM and 69 T2DM patients), and 361 implants in 90 non-diabetic patients. RESULTS: The results suggested that jaw (greater MBL in the maxilla), diabetes (greater MBL for diabetic patients, and worse for T1DM patients), bruxism (greater MBL for bruxers), and smoking (greater MBL for smokers and former smokers) had a statistically significant influence on MBL over time. CONCLUSIONS: Patients with diabetes have an estimated greater MBL over time compared to non-diabetic patients. The difference was greater in patients with diabetes type 1 compared to patients with diabetes type 2. Bruxism, smoking, and implant location (maxilla) were also associated with a higher loss of marginal bone around implants over time. CLINICAL RELEVANCE: Awareness of the possible influence of diabetes on the long-term outcomes of dental implant treatment is important, in order to be able to minimize the possibility of a high MBL with time, which can eventually lead to the loss of the implant.