Radiographic Marginal Bone Levels Research Articles

Effect of one-time placement of the definitive abutment versus multiple healing abutment disconnections and reconnections during the prosthetic phase on radiographic and clinical outcomes: A 12-month randomized clinical trial.

The aim of this investigation was to evaluate the effect on clinical and radiological outcomes of the one-abutment, one-time protocol (test) versus placing the definitive abutment on the day of functional loading after having disconnected and connected three times the healing abutment during the prosthetic phase (control). Forty patients with 80 implants were randomly allocated to either the test or the control group. Changes in the radiographic marginal bone levels (MBLs), clinical outcomes, prosthetic-related outcomes, and patient-reported outcomes measures (PROMs) were assessed and compared 6 and 12 months after functional loading. Thirty-seven patients with 74 implants were followed at 12 months. A statistically significant bone remodeling was observed in both groups following implant placement. MBLs were significantly greater in the control group at the 6- (-0.13 mm vs. -0.61 mm) and 12-month visits (-0.01 mm vs. -0.53 mm). Bone loss was significantly greater in the control group from surgery to 6 and 12 months and from loading to 6 and 12 months. The abutment height was significantly greater in the test group, however, there were no significant differences in the restorative angle. Similarly, there were no statistically significant differences between groups for the measured clinical variables (probing depth, plaque, and bleeding index) and PROMs. Disconnecting and reconnecting the healing abutment was associated with significantly higher bone loss after 12 months, as compared to the placement of the definitive abutment at implant installation.

Progressive bone loss and bleeding on probing: A cohort study.

To investigate whether a progressive marginal bone loss (PMBL) occurring beyond the initial bone remodeling (IBR) is linked with bleeding on probing. A total of 70 partially edentulous patients exhibiting 112 two-piece bone-level implants were included in this retrospective study. Panoramic radiographs were obtained after implant insertion (T0), after delivery of a final prosthetic restoration (T1) and subsequently during the 1-(T2), 5-(T3), 10-(T4), and 15-years (T5) follow-up visits. At each time point, radiographic marginal bone levels were assessed from the implant shoulder to the first bone-to-implant contact at mesial and distal aspects. The IBR was defined as a bone loss occurring up to prosthesis delivery, that is, from T0 to T1. The PMBL was defined as bone loss occurring after T1. At T2, T3, T4, and T5, the presence or absence of bleeding on probing (BOP) was recorded at four sites. A median regression with mixed models was performed to assess the difference of PMBL in PMBL + BOP+ and PBML + BOP- groups. Over the mean implant functioning time of 4.44 ± 4.91 years, 38 (34%) implants showed no PBML, whereas 74 (66%) implants featured PMBL. Of these, 35 (47%) and 39 (53%) implants were assigned to the PMBL + BOP- and PMBL + BOP+ groups, respectively. The mean PMBL after 1, 5, 10, and 15 years were comparable between implants featuring PMBL with or without BOP. At 1 year, BOP intensity significantly correlated PMBL, with each increase in one BOP-positive site being associated with increase in PMBL by 0.55 mm (p = 0.038), whereas this association was not found at 5, 10, and 15 years. The IBR values in the no PBML, PMBL + BOP+, and PBML + BOP- groups were -0.24 ± 0.31, -0.41 ± 0.59, and -0.24 ± 0.33 mm, respectively, with no significant differences found among the groups. Progressive bone loss at implant sites is not always linked with bleeding on probing.

Electrolytic Surface Decontamination in the Reconstructive Therapy of Peri-Implantitis: Single-Center Outcomes of a Randomized Controlled Trial.

Surface decontamination in the reconstructive therapy of peri-implantitis is of paramount importance to achieve favorable outcomes. The objective of this single-center study derived from a large multicenter clinical trial was to compare the electrolytic method (EM) used as an adjunct to mechanical decontamination, to hydrogen peroxide (HP) also used as an adjunct to mechanical decontamination, in the reconstructive therapy of peri-implantitis. At 12-month (T2) follow-up, 19 patients (Nimplants= 23) completed the study. None of the tested modalities demonstrated superiority in terms of the assessed clinical parameters. Only mucosal recession showed higher stability in the EM group. Alike, radiographic marginal bone level gain and defect angle changes at T2 did not differ between the evaluated strategies. Notably, disease resolution was ∼16% higher in the EM; however, differences did not reach statistical significance. Additionally, it was demonstrated that pocket depth and intra-bony component depth at baseline were predictors of disease resolution. In conclusion, the EM combined with mechanical instrumentation results in a safe and effective surface decontamination modality in the reconstructive therapy of peri-implantitis. This strategy resulted in ∼91% disease resolution rate.

Clinical and Biological Validation of an Allogeneous Cancellous Bone Block for Alveolar Maxillary Ridge Reconstruction: A Case Series.

This exploratory case series clinically and histologically investigated the performance of allogeneic cancellous freeze-dried bone allograft (FDBA) bone blocks (Maxgraft®) for the lateral augmentation of local alveolar defects in the posterior maxilla as part of two-staged implant therapy. Five patients receiving eight implants 5 months after block augmentation with a follow-up period of up to 3 years were documented and analyzed. Horizontal alveolar dimensions before and 5 months after block augmentation were quantified using CBCT. Radiographic marginal bone level changes were quantified at implant placement, loading, and 1 year post-placement. Graft integration and resorption were histologically qualitatively evaluated from core biopsies retrieved at implant placement. Block augmentations resulted in a pronounced horizontal median bone gain of 7.0 (5.5 to 7.8) mm. Marginal implant bone levels in block-augmented bone remained constant over the 1 year follow-up period. Block grafts appeared histologically well integrated. Histologic analysis also revealed signs of progressive resorption and new bone formation at the lateral aspects of the grafts. The results of this case series support using Maxgraft® cancellous FDBA blocks as suitable materials for the lateral augmentation of local alveolar defects.

Effects of maintenance implant therapy with and without periodic removal and decontamination of prosthetic components on inflammatory peri-implant parameters.

A retrospective analysis based on patient records was used to assess inflammatory clinical and biochemical parameters around dental implants installed by the same clinician in a private clinic. The plaque index (PI), peri-implant probing depth (PPD), mucosa! recession (MR) bleeding on probing (BOP) and radiographic marginal bone level were determined at baseline and at each year during the follow-up period. Moreover, at last follow-up visit the peri-implant intrasulcular levels of active metalloproteinasis 8 (aMMP-8) were also assessed. All participants were under MT with a 6-month recall interval. Ninety-two patients with 132 implants were selected. At the end of the study period, 12 patients with 12 implants were classified as "dropouts". Remained 80 patients and 120 implants were classified into two groups: Group 1, (42 patients with 62 implants) received MT with periodic removal and decontamination of prosthetic components; Group 2, (38 patients with 58 implants) received MT without periodic removal and decontamination of prosthetic components. No statistical differences were found between the groups regarding presence of plaque, probing depth, and mean mucosal recession. Group 1 presented a statistically significant higher number of sites with BOP (12.4% vs. 6.2%). Marginal bone loss was statistically higher in Group 2 than in Group 1 (0.23 ± 0.6 mm vs. and 0.78 ± 0.3 mm). Intrasulcular levels of aMMP-8 were statistically higher in Group 1 than in Group 2. The supplemental application of periodic removal and decontamination of prosthetic components during MT had a significant additional benefit in the peri-implant tissues inflammatory status.

Clinical and radiographic outcomes of implant-supported zirconia fixed dental prostheses with cantilever extension: Aproof-of-principle study with a follow-up of at least 1 year.

To test the reliability of full zirconia implant-supported fixed dental prostheses with cantilever extension (FDPCs) after at least 1 year of function. Thirty-five patients in need of implant-supported single unit crowns (SUC) and FDPCs in posterior areas were enrolled. After implant placement, patients were rehabilitated with screw-retained full-zirconia FDPCs. Implant survival rate, pocket probing depth (PPD), presence/absence of bleeding on probing (BoP), and presence/absence of mechanical/technical complications were recorded. Mesial and distal radiographic marginal bone levels (mBLs) from baseline (i.e., recall appointment 3-6 months after implant loading [T0]) to the follow-up examination (i.e., latest recall appointment after at least 12 months after T0 [T1]), were calculated. Thirty patients with 34 FDPCs (31 SUCs and 3 FDPs) supported by 37 implants were available for analysis after a mean loading time of 2.6 ± 1.5 years (range: 13-87 months). No implants were lost. MBLs and mean PPD values did not change statistically significantly from T0 to T1 from 0.92 mm ± 0.42 to 0.96 mm ± 0.38 (95% CI: -0.07/0.17; p = .418) and from 2.99 mm ± 0.70 to 3.27 mm ± 0.71 (95% CI: -0.11/0.68; p = .25) respectively. Peri-implant mucositis was diagnosed in 22 cases. Screw-loosening and zirconia chipping occurred 1× in 4 patients. Within the limitations of the present proof-of-principle study, the use of full-zirconia FDPCs in posterior areas seems a valid and safe short-term treatment option.

Radiographic marginal bone level evaluation around two different tissue-level implant systems: a one-year prospective study.

Marginal bone loss, is a frequently reported variable in the evaluation of dental implants. The primary objective of this study was to evaluate radiographic marginal bone level changes around the two different tissue-level implant systems placed adjacently in the posterior maxilla or mandible. The influence of implant macro-geometry and vertical soft tissue thickness on marginal bone loss were also evaluated. Seven patients were included in the study and a total of 18 implants were analyzed. Each patient received two different implants placed adjacently in the maxilla or the mandible. The implants used in our study were either Straumann® SP cylindrical implants or JD Octa® tapered implants. During the surgery, vertical soft-tissue thickness was measured with a periodontal probe placed on the top of the bony crest and in the center of the future implant site. Healing abutments were then seated. Three months following implant placement, impressions were taken, and screw-retained metal ceramic prostheses were delivered. Standardized intraoral radiographs were taken immediately after implant placement and one year following implant loading in order to assess marginal bone level changes. Results showed a mean marginal bone loss of 0.55±0.5 mm for Straumann® SP implants and 0.39±0.49 mm for JD Octa® implants after one year of loading and the difference was not statistically significant between the two systems. A statistically significant correlation was found between soft tissue thickness and marginal bone loss; in sites with thin mucosal tissues (≤2 mm), there was significantly greater bone loss compared to sites with thick, soft tissues (> 2 mm) in both implants. Radiographic marginal bone loss was not statistically different between the two implant systems at the one-year examination period. Moreover, vertical soft tissue thickness influenced marginal bone loss regardless of the implant system used.

Healing of Endosseous Implants Having Different Surface Characteristics in the Alveolar Bone: A Clinical Study.

Background Total treatment time in implant placement can be significantly reduced by placing immediate implants into the freshly extracted sockets. Also, immediate implant placement can act as a guide for proper and accurate implant placement. Additionally, in immediate implant placement, the resorption of bone associated with the healing of the extraction socket is also reduced. This clinical study aimed to clinically and radiographically assess the healing of endosseous implants having different surface characteristics in nongraftedand grafted bone. Methodology In 68 subjects, 198 implants were placed, including 102 oxidized (TiUnite, Göteborg, Sweden) and 96 turned surface implants (Nobel Biocare Mark III, Göteborg) were placed. Survival was considered with clinical stability and acceptable function with no discomfort and no radiographic or clinical signs of pathology/infection. Rest cases that showed no healing and implant no osseointegration were considered failures. Clinical and radiographic examination was done by two experts aftertwo years of loading based on bleeding on probing (BOP) mesially and distally, radiographic marginal bone levels, and probing depth (mesial and distal). Results Fiveimplantsfailed in total where four implants were with the turned surface (Nobel Biocare Mark III) and one was from the oxidized surface (TiUnite). The one oxidized implant was in a 62-year-old female and was placed in the region of mandibular premolar (44) of length 13 mm and was lost within five months of placement before functional loading. Mean probing depth had a nonsignificant difference between oxidized and turned surfaces with the mean values of 1.6 ± 1.2 and 1.5 ± 1.0 mm, respectively, with P= 0.5984; mean BOPin oxidized and turned surfaces was 0.3 ± 0.7 and 0.4 ± 0.6, respectively (P= 0.3727). Marginal bone levels, respectively, were 2.0 ± 0.8 and 1.8 ± 0.7 mm (P= 0.1231). In marginal bone levels related to implant loading, a nonsignificant difference was seen in early loading and one-stage loading with P-values of 0.06 and 0.09, respectively. However, in two-stage placement, significantly higher values were seen for oxidized surfaces (2.4 ± 0.8 mm) compared to turned surfaces (1.9 ± 0.8 mm), with P= 0.0004. Conclusions This study concludes that nonsignificantly higher survival rates are associated with oxidized surfaces compared to turned surfaces after two years of follow-up. Higher marginal bone levels were seen in oxidized surfaces for single implants and implants placed in two stages.

Early marginal bone loss around dental implants to define success in implant dentistry: A retrospective study.

The aim of this study was to establish an objective criterion in terms of marginal bone level (MBL) to know the prognosis of an implant. A group of 176 patients in whom 590 implants were placed were included in this retrospective study. Patients older than 18 years, presenting either Kennedy class I or II edentulous section, or totally edentulous at least in one of the dental arches were included in this study. Those with any type of disturbance able to alter bone metabolism or with nontreated periodontal disease were excluded. Data on radiographic MBL at loading, 6 and 18 months later, age, gender, smoking habits, history of periodontitis, bone substratum, implant, and prosthetic features were recorded. Nonparametric receiver operating curves (ROC) were constructed for the MBL at 18 months in order to establish a distinction among high bone loser (HBL) and low bone loser (LBL) implants. Differences as a function of main variables were also determined, particularly abutment height and periodontal disease. HBL implants lost at least 0.48 mm of MBL 6months after loading; they reached at least 2 mm of MBL 18 months after loading. MBL rate followed a nonlinear trend, except in implants restored over long prosthetic abutments and in patients with history of severe periodontitis; in whom the rate of MBL over the time was nearly zero. Implants that lose more than 0.5 mm of marginal bone 6months after loading are at great risk of not being radiographically successful anymore. Therefore, 0.5 mm of MBL is proposed as a distinctive and objective criterion of success in Implant Dentistry within a 6-month follow-up period. A prosthetic abutment height ≥2 mm resulted the most protective factor in the peri-implant bone maintenance.

Are partially edentulous patients with a history of severe periodontitis more prone to develop peri-implantitis over the long term?

Aim This study aimed to compare the long-term outcome of implant therapy in partially edentulous patients with severe periodontitis compared to those with no history of periodontitis.Design Retrospective cohort study.Cohort selection Eighty-eight patients (34 men and 54 women; age ranging from 28 to 45 years) with severe periodontitis (47 patients with 108 implants) and no history of periodontitis (41 patients with 78 implants) were included in this institutional study. All these cohorts had received implants 6-8 years previously.Data analysis Probing pocket depth, radiographic marginal bone level and peri-implantitis were the primary outcomes, while bleeding on probing was the secondary outcome. The effect of variables was measured by odds ratio with 95% confidence interval. Both patient-level and implant-level analyses were used to evaluate the association between peri-implantitis and potential risk factors. In addition, the association between probing pocket depth and radiographic marginal bone level with potential risk factors was assessed at implant-level analyses. In contrast, for patient-level data, a positive relationship was assessed with the Chi-square test.Results Patients with a history of severe periodontitis (OR = 11.13; p = 0.045), implants with a lack (<2 mm) of peri-implant keratinised mucosa (OR = 14.94; p <0.001) and implants placed in bone-grafted sites (OR = 4.93; p = 0.047) were associated with greater risk of peri-implantitis, at 6-8 years post-implant placement. The risk of developing radiographic marginal bone level ≥3 mm was significantly greater (OR = 1.20; p <0.001) in patients with higher full-mouth bleeding scores. The chance of peri-implant bleeding on probing was independently and especially higher in patients who brushed their teeth at most once per day (OR = 3.20; p = 0.04), with higher full-mouth bleeding score values (OR = 1.16; p <0.001) and irregular recall visits (OR = 15.34; p = 0.001).Conclusion This retrospective cohort study concluded that partially edentulous patients with a history of severe periodontitis were more prone to develop peri-implantitis at 6-8 years post-implant placement.

Comparison of clinical outcomes of immediate versus delayed placement of dental implants: A systematic review and meta-analysis.

Two focused questions were addressed: Focused question (Q1) 1) Are there any differences between immediate and delayed placement in terms of (i) survival rate, (ii) success rate, (iii) radiographic marginal bone levels, (iv) height/(v)thickness of buccal wall, (vi) peri-implant mucosal margin position, (vii) aesthetics outcomes and (viii) patient reported outcomes? Focused question 2 (Q2) What is the estimated effect size of immediate implant placement for all parameters included in Q1? An electronic search (MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials and OpenGray) and hand search were conducted up to November 2019. Randomised controlled trials (RCT) with delayed implant placement as controls were eligible in the analysis for Q1. Immediate dental implant arms RCTs, controlled clinical trials (CCTs) and prospective case series of immediate implant placement were eligible in the analysis for Q2. Six papers (RCTs) were included in the analysis for Q1 and 53 papers (22 RCTs, 11 CCTs and 20 case series) for Q2. Q1: Meta-analyses did not show any significant difference in implant survival, but it did for bone levels and PES scores at 1year post-loading, favouring the immediate group. Q2: Meta-analyses showed that immediate implants had a high survival rate (97%) and presented high PES scores (range 10.36 to 11.25). Information regarding marginal bone loss and gingival/papillary recession varied among all included studies. Similar survival rate was found between immediate and delayed implants. Immediate implants presented threefold early complications and twofold delayed complications. Success criteria should be reported more consistently, and the incidence/type of complications associated with immediate implants should be further explored.

Influence of Different Implant Types on Bone Levels After Healing and Peri-implant Tissue Reactions Following Peri-implantitis: A Preclinical Study.

This study evaluated the influence of different implant types on (1) radiographic marginal bone levels after healing and (2) radiographic and histomorphometric tissue levels and characteristics following ligature-induced peri-implantitis. Four implant types (Standard Plus, Straumann [S]; NobelReplace Tapered, Nobel Biocare [N]; In-Kone Universal, Global D [I]; and twinKon, Global D [T]) were randomly placed in the edentulous healed mandibular ridge of six dogs (T0), for a total of 57 implants placed. After 10 weeks, a peri-implantitis was ligature-induced (T1). After 12 weeks, biopsy samples were processed for histomorphometric analysis (T2). Standardized radiographs were taken at T0, T1, and T2 for imaging analysis. Statistical analysis was performed using mixed-effects linear modeling. After healing (T1), the radiographic marginal bone level was more coronal for implants I, T, and S compared to N. Following peri-implantitis (T2), the histologic marginal bone level was more coronal for implants I, T, and S compared to N, and for implants I and T compared to S. Also at T2, the radiographic marginal bone level was more coronal at implants I, T, and S compared to N. Implant type may influence bone remodeling during healing and bone loss during the early stages of experimental peri-implantitis.

Clinical and esthetic outcomes of immediate implant placement compared to alveolar ridge preservation: a systematic review and meta-analysis.

The aim of this systematic review was to evaluate the efficacy of immediate implant placement (IIP) compared to implants placed after alveolar ridge preservation (ARP) in terms of clinical, esthetic, and patient-reported outcomes. A manual and electronic search (National Library of Medicine) was performed for controlled clinical trials, with at least 12months of follow-up. Primary outcome variable was implant survival and secondary outcomes were marginal bone level (MBL) (change), pink esthetic score (PES), mid-facial mucosal level (change), papilla index score, complications, and patient-reported outcomes. A total of 10 publications were included (7 randomized clinical trials and 3 controlled clinical trials). The results from the meta-analyses showed that survival rate was significantly lower in the IIP group compared to ARP group [RR = 0.33; 95% CI (0.14; 0.78); p = 0.01]. No significant differences between the two groups were observed regarding radiographic MBL, PES scores, or mid-facial mucosal level (p > 0.05). The results from this systematic review and meta-analysis showed that IIP had lower survival rates and similar esthetic results when compared to ARP. Clinicians should weigh the benefits and disadvantages of each intervention to select the optimal timing of implant placement.

Interproximal open contacts between implant restorations and adjacent natural teeth as a risk-indicator for peri-implant disease-A cross-sectional study.

The primary aim of this study was to investigate the relationship between interproximal open contacts and peri-implant disease. The secondary aim was to assess patient-reported outcome measures in relation to contact status. A cross-sectional study was performed on 61 patients with 142 implants adjacent to at least one natural tooth. Patients underwent a clinical examination to assess contact status and width, plaque index (PI), gingival index (GI), periodontal probing depths (PPD), and bleeding on probing (BoP). Radiographic marginal bone level was measured in vertical bitewings taken within one year. A diagnosis was given to each implant. Last, subjects completed a brief questionnaire. Rao-scott chi-squared tests and generalized estimating equations (GEE) models were used to compare outcomes between groups. Seventy-seven (54.2%) implants were found to have ≥1 interproximal open contact. Sixty-five (45.8%) implants had closed contacts only. Implants with interproximal open contacts were significantly associated with peri-implant mucositis and peri-implantitis (p=.003) and increased prevalence of peri-implant disease (adjusted PR=1.57; 95% CI: 1.09-2.27, p=.015). Open contact status was also associated with higher PPD (p=.045), PI scores (p=.036), and GI scores (p=.021). Open contact prevalence was 75.4% on the patient-level and 54.2% on the implant-level, involving the mesial surface of the implant restorations 68.5% of the time (p<.001). Interproximal open contacts between implant restorations and adjacent natural teeth are a risk indicator for peri-implant disease. Adequate contact between implant restorations and natural teeth may contribute to the health of peri-implant tissues.

Clinical and radiographic evaluation of implant-supported single-unit crowns with cantilever extension in posterior areas: A retrospective study with a follow-up of at least 10 years.

Implant-supported restorations with cantilever extension may display high rates of biological and technical complications. To report the outcomes of single-unit crowns with cantilever extension (SCCs). Patients with SCCs were reevaluated after ≥10 years of loading. Radiographic marginal bone levels (mBLs) at baseline (ie, delivery of SCCs) and follow-up were calculated and compared between implant surfaces adjacent to and distant from the cantilever extension. Implant survival and success rates were calculated. Twenty-one patients with 25 SCs supported by 25 implants were reevaluated after a mean of 13.6 ± 3.8 years (range: 10-19 years). No implants were lost. The mean overall mBLs changed from 0.99 mm ± 0.95 at baseline to 0.95 mm ± 0.99 at follow-up (p = 0.853). The mean pocket probing depths changed from 3.39 mm ± 0.62 at baseline to 3.34 mm ± 0.54 at follow-up (p = 0.635). Loss of retention occurred 3× in 2 patients (14.3%). At follow-up, peri-implant health was diagnosed in 10 (48%) and peri-implant mucositis in 11 (52%) patients, respectively. Within the limitations of the present study, the use of implant-supported SCs with cantilever extension in posterior areas represents a reliable long-term treatment option with a 100% implant survival rate and minimal marginal bone level changes.

Crestal bone changes around early vs. conventionally loaded implants with a multi-phosphonate coated surface: A randomized pilot clinical trial.

To compare the marginal bone level around implants with a thin multi-phosphonate coated surface after either an early or conventional loading protocol. A randomized pilot clinical trial was conducted. Dental impressions were obtained after either 4 (test) or 8weeks (control) and single crowns screwed-in 2weeks later. Several variables were evaluated including radiographical marginal bone level (MBL), patient's level variables, and those related to the restoration and surrounding tissues. These data were obtained at several time points up to a 1-year follow-up. Thirty-four patients were included in the study, 18 assigned to the test group. No differences at implant placement were detected for tissue thickness, keratinized mucosa, nor any other clinical or radiological variable. At the time of impressions, tissue was thinner in the test group (2.30 (0.46) versus 2.78 (0.66) mm, test versus control, respectively; p=.012) so shorter abutments were used in this group. Regardless, no significant changes in marginal bone level were detected neither within group along time nor between groups. The average MBL at the 1-year follow-up was -0.15 (0.32) versus -0.22 (0.37) (p=.443) (test versus control, respectively). None of the clinical or radiological variables evaluated had a determinant influence on the MBL at any visit nor group. The use of implants with a multi-phosphonate coated surface for early loading offers successful radiographical outcomes 1year after loading. MBL over time was not affected by taking the impressions 4 or 8weeks after implant placement and loading them 2weeks later.

Clinical and radiographic outcomes of implant-supported fixed dental prostheses with cantilever extension. A retrospective cohort study with a follow-up of at least 10 years.

To report the clinical and radiographic outcomes of implant-supported fixed dental prostheses with cantilever extensions (FDPCs) after a function time ≥10years. Patients with FDPCs in posterior areas were clinically and radiographically re-evaluated. Mesial and distal radiographic marginal bone levels (mBLs) from baseline (i.e. delivery of FDPC) to the follow-up examination were calculated and compared between implant surfaces adjacent to and distant from the cantilever extension. Implant survival rate, pocket probing depth (PPD), presence/absence of bleeding on probing (BoP) and presence/absence of mechanical/technical and biological complications were recorded. Twenty-six patients with 30 FDPCs supported by 60 implants were re-evaluated after a mean loading time of 13.3±2.7years (range: 10-18.6years). One diameter-reduced implant carrying a cantilever extension fractured, yielding a patient-based survival rate of 96.2% (95% CI: 0.95/1.0). The mean marginal bone level change was not statistically significantly different from baseline to follow-up (1.2mm±0.9 to 1.6mm±1.7; 95% CI: -0.1/0.9; p>.05). The mean PPD changed statistically significantly from 3.4mm±0.7 to 3.7mm±0.7 (95% CI: 0.04/0.6; p=.02). Loss of retention occurred≥1x in 9 patients (34.6%, 95% CI: 0.44/0.83). At follow-up, peri-implant health was diagnosed in 12 (46.2%), peri-implant mucositis in 7 (26.9%) and peri-implantitis in 7 (26.9%) patients, respectively. Despite a high rate of loss of retention, the use of implant-supported FDPCs in posterior areas represents a reliable long-term treatment option with a high implant survival rate and minimal peri-implant bone level changes irrespective of the location of the cantilever extension.

Five Degree Internal Conical Connection and Marginal Bone Stability around Subcrestal Implants: A Retrospective Analysis

Background: There is limited information on the effect of the connection between subcrestally placed implants and abutments on marginal bone levels. The aim of the present retrospective study was to evaluate marginal bone levels after definitive prosthesis delivery around implants with an internal 5° conical connection placed in a subcrestal position. Materials and methods: Patients treated with fixed prostheses supported by implants placed at a subcrestal level between 2012 and 2018 were recalled for a follow-up examination. All implants had 5° internal conical connection with platform switching. Radiographic marginal bone level (MBL) was measured. MBL change between prosthetic delivery (t0) and follow-up examination (t1) was calculated. A multiple regression model was performed to identify the most significant predictors on MBL change. Results: Ninety-three patients and 410 implants, with a mean follow-up of 2.72 ± 1.31 years, were examined. Mean MBL was −1.09 ± 0.65 mm and −1.00 ± 0.37 mm at t0 and t1, respectively, with a mean bone remodeling of 0.09 ± 0.68 mm. An implant’s vertical position in relation to the bone crest, the year of follow up and the presence of type-2 controlled diabetes were demonstrated to be influencing factors for MBL modifications. Conclusions: Subcrestally placed implants with platform switching and internal conical connection maintained stable bone levels over a mean follow-up of more than 2 years. How a tight internal conical connection between abutment and implant may contribute to this clinical evidence should be more deeply investigated. MBL variations seem to be mostly influenced by an implant’s vertical position and presence of type-2 controlled diabetes.

Evaluation of Autogenous Bone Graft around Dental Implant Alone or Combined with Melatonin gel: Randomized Control Trial

Purpose: The present study was conducted to evaluate the effect of autogenous bone graft on the osseointegration of early loaded dental implant either alone or combined with Melatonin gel. Material and Methods: The study was including 10 patients with 20 numbers of sites and age range of 22-52 years. The study groups were designed in two groups, test group treated surgically with dental implant after application of autogenous bone graft mixed with (1.2mg) melatonin gel. Control group treated surgically with dental implant after application of autogenous bone graft alone. Results: Clinically, in both groups, there was change in gingival thickness with significant difference within test group. Regarding radiographic marginal bone levels measurements; in both groups the mean marginal bone loss was increased by time, with significant difference between both groups in favor of test group. Conclusions: Early loaded dental implants can be successfully used to reduce the healing period. The adjunctive topical use of melatonin seems to have a more valuable outcome in promoting the early osseointegration which reflect the meaningful in clinical and radiographic improvement.

Changes of Radiographic Trabecular Bone Density and Peri-Implant Marginal Bone Vertical Dimensions Around Non-Submerged Dental Implants with a Laser-Microtextured Collar after 5 Years of Functional Loading.

Objectives: The progressive peri-implant bone remodeling caused by dynamic cycles of microdamage may change peri-implant bone characteristics and volume after the functional loading. This prospective study was designed to evaluate the radiographic trabecular bone density and peri-implant vertical dimensional changes around the non submerged dental implant with a laser-microtextured collar (NSLI)s after 5 years of functional loading. Methods: Digital periapical radiographs of 58 NSLIs supported fixed single crowns and fixed partial dentures in 26 patients (14 men, mean age of 52 ± 3.8 years) were used for comparative evaluation between the implant placement [Baseline (BSL)], the definitive Crowns Delivery (CD) and the 5 years post-functional loading examination (T5). Regions of interest (ROI) were taken into consideration for the measurement of mean gray levels, standard deviation, and variation coefficient. The texture parameters, such as contrast, correlation, angular second moment and entropy, were investigated by using the software ImageJ (v.1.50i), by means of the Gray-level Co-occurrence Matrix (GLCM) Texture Tool plugin. Vertical Peri-implant Marginal Bone Level (VPMBL) was assessed at the mesial and the distal sides of each implant by subtracting the measure at BSL from the measure at T5 by means of dedicate software (VixWin Platinum Imaging Software). Mixed regression models were adopted to analyze data. The possible effects of some variables, such as the use of provisional denture, location, crown/implant ratio, type of prosthetic design (single or splinted), on radiographic dimensional vertical changes, gray levels and texture analysis variables were also evaluated. Results: From BSL to T5, mesial and distal VPMBL showed a statistically significant gain of 0.9 ±0.5, and 0.10 mm ±0.6, respectively (P&lt;0.05). From CD to T5, mean gray levels increased from 94.4±26.8) to 111.8±27.1 (P&lt;0.05), while the coefficient of variation decreased from 0.08±0,03 to 0.05±0.04) (P&lt;0.05). Variables showed no statistically significant correlation with texture parameters (P &gt; 0.05). Conclusion: NSLIs showed an increase in radiographic vertical peri-implant marginal bone levels and bone density up to 5 years of loading.