Mean Bone Level Change Research Articles

Evaluation of the clinical safety and performance of a narrow diameter (2.9 mm) bone-level implant: a 1-year prospective single-arm multicenter study

PurposeNarrow-diameter implants facilitate single‐tooth restoration when interdental or inter-implant spaces and bone volume are inadequate for using standard diameter implants. This study reports the short-term data on the clinical safety and performance of a bone-level-tapered two-piece implant with a 2.9 mm diameter in the clinical practice setting. This study was retrospectively registered on March 1st, 2016 (NCT02699866).MethodsImplants were placed in partially healed extraction sockets of the central and lateral incisors in the mandible and lateral incisors in the maxilla for single-tooth replacement. The primary outcome was to assess implant survival at 12 months after placement. Secondary outcomes included implant success, pink esthetic score, marginal bone-level changes, and safety.ResultsTwenty four males and 17 females with a mean age of 44.5 (± 18.3 standard deviation) received the implant. Three out of 41 implants were lost yielding a survival rate of 92.7% (95%-CI: 79.0%; 97.6%) at 1 year. One patient reported an ongoing foreign body sensation, pain, and/or dysesthesia at month 12. The average pink esthetic score at 6 months was 11.2 (95%-CI: 10.5; 11.9). The bone level was stable with a mean bone-level change of—0.3 mm (± 0.42 mm standard deviation) at 1 year after implantation. No serious adverse events or adverse device events were reported.ConclusionsThe use of a 2.9 mm diameter bone-level-tapered implant is a safe and reliable treatment option for narrow tooth gaps at the indicated locations. Overall performance and good survival rates support their use in cases, where wider implants are unsuitable.Graphical abstract

Long-Term Effect of Guided Implant Surgery on Clinical Outcomes and Peri-Implantitis of Maxillary Implants-An Observational Cohort Study.

(1) Although the accuracy of static computer-aided implant surgery (sCAIP) is well reported, information on its long-term effect on peri-implant health and complications is scarce. (2) Twenty-six patients initially treated were recalled. Implant survival, radiographic bone level, peri-implant health, and complications were registered. A multilevel regression model was applied to study the relationship between the research variables. (3) Sixteen patients participated in this study (average age 58.5 years; range 27.8-73.8). The mean follow-up time was 9.1 years (range 7.3-11.3). Two implants failed, resulting in a survival rate of 97.1%. The mean bone level change corresponded to a loss of 0.63 mm (SD 1.90) for the whole group, 0.17 mm (SD 1.46), and 0.91 mm (SD 2.09) for tooth- and mucosa-supported guides, respectively. The mean PPD for the total group was 4.24 mm (SD 1.25), and 3.79 mm (SD 0.97) and 4.51 mm (SD 1.33) for the tooth- and mucosa-supported guides, respectively. Four implants (6.3%) were diagnosed with peri-implantitis. Coronal deviation was slightly associated with having a negative impact on bone level at follow-up, but this was not statistically significant. Seven patients (43.8%) experienced technical complications. Biological complications were seen in 3/16 patients (18.75%). (4) SCAIP may contribute to more predictable implant placement; the long-term clinical outcome is similar to conventional nonguided surgery.

Marginal bone level changes around dental implants with one or two adjacent teeth - A clinical and radiographic retrospective study with a follow-up of at least 10 years.

To compare mean bone level (mBL) changes around dental implants with one or two adjacent teeth after a function time of ≥10 years. One hundred thirty three periodontally compromised patients (PCPs) with 551 implants enrolled in supportive periodontal care (SPC) were screened. Implants were categorized either into group TIT (tooth-implant-tooth) or into group TIG (tooth-implant-gap). MBL changes from delivery of restoration (i.e., baseline) to follow-up were calculated in millimeters and compared between implants and adjacent teeth. Survival rates and the need for surgical interventions during SPC were recorded. Eighty seven patients with 142 implants were re-evaluated after a mean observation time of 14.5 ± 3.5 years. The mBL at mesial implant sites in the TIT group increased -0.07 ± 0.92 mm and decreased in the TIG group 0.52 ± 1.34 mm, respectively (95% CI: 0.04/1.14, p = .037). At distal implant sites, the mBL in the TIT group increased -0.08 ± 0.84 mm and decreased 0.03 ± 0.87 in the TIG group, respectively (95% CI: -0.20/0.42, p = .48). The overall implant loss rate was 3.5% (n = 5; 2 TIT, 3 TIG), without a statistically significant difference between the two groups (95% CI: 0.18/7.07, p = .892). Tooth loss rates (TIT: 12.3%, TIG: 12.3%) were not statistically significantly different (OR = 1.00, p = .989). High tooth and implant survival rates were observed in PCPs. The presence of one or two adjacent teeth seemed to have no impact on marginal bone level changes.

Reconstructive treatment of peri-implant defects-Results after three and five years.

The aim of this study was to assess the long-term efficacy of reconstructive treatment of peri-implantitis intraosseous defects. Peri-implant intraosseous defects were augmented using either an autogenous bone graft (AB) or a bovine-derived xenograft (BDX) in combination with a collagen membrane. Maintenance was provided every third month. In the AB group, 16 patients with 25 implants remained at year five. In the BDX group, 23 patients with 38 implants remained. Between baseline and year 5, bleeding on probing (BOP) and probing pocket depth (PPD) scores were reduced in both groups (p< .001). In the AB and BDX groups, mean PPD between baseline and year five was reduced by 1.7 and 2.8 mm, respectively. The difference between groups was significant (p< .001). In the AB group, the mean bone level change at implant level between baseline and years three and five was-0,2 and -0.7 mm, respectively. In the BDX group, the mean bone level change at implant level between baseline and years three and five was 1.6 and 1.6 mm, respectively. The difference between the groups was significant (p< .001). Successful treatment(no bone loss, no probing pocket depth (PPD) > 5 mm, no suppuration, maximum one implant surface with bleeding on probing (BOP) at year five) was obtained in 9/25 implants (36%) in the AB group and in 29/37 implants (78.3%) in the BDX group. Reconstructive surgical treatment of peri-implant defects using BDX resulted in more predictable outcomes than using autogenous bone over 5 years.

Immediate versus delayed temporization at posterior single implant sites: A randomized controlled trial.

We conducted a randomized controlled trial to assess the clinical outcomes of two loading protocols involving either immediate or delayed prosthetic temporization of single implants placed at posterior, healed sites. Forty-nine patients in need of single implants at premolar or molar sites were randomized to receive a temporary crown either immediately after implant placement or 3months later. Randomization was stratified by sex, implant location (premolar/molar) and arch (maxilla/mandible). Final implant screw-retained zirconia crowns with angulated screw channels were delivered at 5months after surgery. Radiographic bone levels (primary outcome), peri-implant mucosal margin levels and peri-implant probing depths were recorded at baseline, 6 and 12months after surgery. Both treatment arms showed similar patterns of soft tissue and bone re-modelling from the implant platform over 12months [mean bone level change 1.6mm (SD 1.0mm) in the delayed, and 1.2mm (SD 1.3mm) in the immediate temporization group], with the majority of changes occurring within the first 6months. Immediate or delayed temporization of single implants placed at posterior healed sites resulted in largely similar 1-year outcomes with respect to peri-implant bone levels and soft tissue changes.

Performance of bone-level implants with conical connections in the anterior maxilla: A 5-year prospective cohort study.

To assess clinical, radiographic and aesthetic outcomes, and satisfaction of patients treated with single implant restorations in the maxillary aesthetic region 5years after final restoration. Sixty patients (29 male/31 female, mean age 37years) with a missing anterior tooth in the maxilla (39 central incisors/10 lateral incisors/5 cuspids/6 first premolars) received a bone-level implant with conical connection. In 29 patients, a bone augmentation procedure was necessary before implant placement (autogenous bone grafts mixed with spongiosa granules). All implants (12 with 3.3mm diameter/ 48 with 4.1mm diameter) were loaded after 3months of submerged healing. The restoration consisted of an individually designed full-zirconia abutment veneered with porcelain. Follow-up with clinical and radiographic assessment was conducted until 60months after the final restoration. Aesthetic outcome of the restoration was determined with the Pink Esthetic Score-White Esthetic Score (PES-WES). Patient satisfaction was assessed with a VAS scale and satisfaction questionnaire. Fifty patients completed the 5-year follow-up. Implant survival was 100%, restoration survival 98%. Mean bone-level change was -0.13±0.66mm with a median (IQR) pocket probing depth of 2.75 [2.25; 3.25]. The mean PES and WES scores were 6.6±1.7 and 7.8±1.5, respectively. Patient satisfaction was high (92.1±7.8 on 100mm VAS scale). There were no differences between patients with or without a bone augmentation procedure. Bone-level implants with a conical connection are a reliable treatment option in single-tooth replacements in the maxillary aesthetic zone.

Immediate versus early loading protocols of titanium—zirconium narrow‐diameter implants for mandibular overdentures in edentulous patients: 1‐year results from a randomized controlled trial

The purpose of this randomized clinical trial was to compare immediate and early loading protocols for mandibular overdentures with two-splinted narrow-diameter implants in thin, non-augmented residual ridge situations. Each edentulous patient received two implants in the interforaminal region. If primary stability after implant placement was achieved, patients were randomized either to the immediate (48hr post-surgery) or the early (2weeks after surgery) loading group. In prosthetic rehabilitation, a bar prosthetic system with a titanium bar was used. Implant survival, success rates, and radiographic changes at the crestal bone level were evaluated after 1year, and patient satisfaction was recorded at 1 and 6months post-surgery. Twenty-four patients with a mean age of 67±9years were included. One patient passed away after 11months due to treatment-independent reasons. In the 24 implants of the immediate loading group, the mean bone level change from surgery/loading to the first-year evaluation was 0.32±0.80mm (p=.066). Regarding the early group (22 implants), the mean bone level change from loading to 1year was 0.34±0.69mm (p=.048). After 1year, no differences could be detected between groups (p=.91) with a mean difference of 0.02mm (95% CI: [-0.42, 0.47]). The mean implant survival and success rates were 100% for both groups. Patient satisfaction was high; however, at 6months, there was a difference between groups regarding the ability to chew. Both loading protocols for mandibular overdentures supported by two-splinted narrow-diameter implants were successful at the 1-year follow-up.

A Randomized, Controlled, Multicenter Clinical Study Evaluating The Crestal Bone Level Change Of SLActive Bone Level Ø 3.3 mm Implants Compared To SLActive Bone Level Ø 4.1 mm Implants For Single-Tooth Replacement.

The purpose of this prospective randomized clinical trial was to test the hypothesis that narrow-diameter titanium-zirconium (Ti-Zr) alloy implants with a chemically modified hydrophilic surface are not inferior in regard to crestal bone level change compared with standard-diameter implants with the same implant surface and material (control). This multicenter study included 50 patients in need of a single tooth replacement in the anterior (canine to canine) or premolar region of the mandible or maxilla. Patients were included if the site could accommodate a 4.1-mm-diameter implant. Implants were temporarily restored at 3 to 4 weeks after placement. Definitive restorations were delivered 4 to 6 months after placement. Patients returned 1 year after implant loading for clinical measurements and radiographic examination. The primary outcome was mean crestal bone level changes measured between implant loading and 12 months postloading. Secondary outcomes included implant success, survival, gingival recession, and patient satisfaction. Fifty patients were enrolled; 47 completed the study. Twenty-three patients were in the narrow-diameter implant group (test), and 24 patients were in the standard-diameter implant group (control). The success and survival rates at 12 months postloading were 100% for both groups. The change in the mean crestal bone level from implant loading to 12 months postloading around narrow-diameter implants was -0.27 ± 0.34 mm. For the standard-diameter implants, the change was significantly higher at -0.48 ± 0.67 mm (P = .02). No significant difference was found in gingival recession and patient satisfaction. The results of this prospective randomized clinical trial suggest noninferiority of the narrow- vs standard-diameter Ti-Zr implant. In addition, bone remodeling was less pronounced for the narrow-diameter implants.

Mean annual attachment, bone level, and tooth loss: A systematic review.

Rate of progression of periodontitis has been used to inform the design of classifications of periodontal diseases. However, the evidence underpinning this topic is unclear and no systematic review has yet been conducted. The focused question for this systematic review was: in adults, what is the progression of periodontitis in terms of clinical attachment loss, radiographic bone loss, and tooth loss? Highly sensitive electronic search was conducted for published data in MEDLINE, EMBASE, LILACS, and unpublished grey literature in OpenGrey up to February 2016. Reference lists of retrieved studies for full-text screening and reviews were hand-searched for potentially eligible studies. Prospective, longitudinal observational studies with follow-up of at least 12 months and presenting data on the primary outcome, change in clinical attachment level, in adults (age ≥18 years). Secondary outcomes, tooth loss and bone level change, were only assessed in studies reporting the primary outcome. Studies investigating specific disease populations or only on treated periodontitis patients were excluded. Risk of bias and methodology were assessed using the Newcastle-Ottawa Scale with two additional questions on security of outcome assessment. Studies were pooled by abstracting or estimating mean annual attachment or bone level change and annual tooth loss. Random effects meta-analysis was conducted with investigation of effect of potential modifiers where possible. A total 11,482 records were screened for eligibility; 33 publications of 16 original studies reporting on more than 8,600 participants were finally included as eligible for the review. The studies represented populations from both developing and developed economies. Mean annual attachment loss was 0.1mm per year (95% CI 0.068, 0.132; I2 =99%) and mean annual tooth loss was 0.2 teeth per year (95% CI 0.10, 0.33; I2 =94%). Observational analysis of highest and lowest mean attachment change quintiles suggested substantial differences between groups with minimal annual change in the lowest quintile and an average deterioration of 0.45mm mean attachment loss per year in the highest group. This value increased to 0.6mm per year with periodontitis alone. There was surprisingly little effect of age or gender on attachment level change. Geographic location, however, was associated with more than three times higher mean annual attachment loss in Sri Lanka and China (0.20mm, 95% CI 0.15, 0.27; I2 =83%) vs North America and Europe (0.056mm, 95% CI 0.025, 0.087; I2 =99%) P<0.001. There were a limited number of studies (N=16), high variability of design in key study components (sampling frames, included ages, data analyses), and high statistical heterogeneity that could not be explained. Within the limitations of the research, the data show that mean annual attachment level change varies considerably both within and between populations. Overall, the evidence does not support or refute the differentiation between forms of periodontal diseases based upon progression of attachment level change.

Mean annual attachment, bone level, and tooth loss: A systematic review

Rate of progression of periodontitis has been used to inform the design of classifications of periodontal diseases. However, the evidence underpinning this topic is unclear and no systematic review has yet been conducted. The focused question for this systematic review was: in adults, what is the progression of periodontitis in terms of clinical attachment loss, radiographic bone loss, and tooth loss? Highly sensitive electronic search was conducted for published data in MEDLINE, EMBASE, LILACS, and unpublished grey literature in OpenGrey up to February 2016. Reference lists of retrieved studies for full-text screening and reviews were hand-searched for potentially eligible studies. Prospective, longitudinal observational studies with follow-up of at least 12 months and presenting data on the primary outcome, change in clinical attachment level, in adults (age ≥18 years). Secondary outcomes, tooth loss and bone level change, were only assessed in studies reporting the primary outcome. Studies investigating specific disease populations or only on treated periodontitis patients were excluded. Risk of bias and methodology were assessed using the Newcastle-Ottawa Scale with two additional questions on security of outcome assessment. Studies were pooled by abstracting or estimating mean annual attachment or bone level change and annual tooth loss. Random effects meta-analysis was conducted with investigation of effect of potential modifiers where possible. A total 11,482 records were screened for eligibility; 33 publications of 16 original studies reporting on more than 8,600 participants were finally included as eligible for the review. The studies represented populations from both developing and developed economies. Mean annual attachment loss was 0.1mm per year (95% CI 0.068, 0.132; I2 =99%) and mean annual tooth loss was 0.2 teeth per year (95% CI 0.10, 0.33; I2 =94%). Observational analysis of highest and lowest mean attachment change quintiles suggested substantial differences between groups with minimal annual change in the lowest quintile and an average deterioration of 0.45mm mean attachment loss per year in the highest group. This value increased to 0.6mm per year with periodontitis alone. There was surprisingly little effect of age or gender on attachment level change. Geographic location, however, was associated with more than three times higher mean annual attachment loss in Sri Lanka and China (0.20mm, 95% CI 0.15, 0.27; I2 =83%) vs North America and Europe (0.056mm, 95% CI 0.025, 0.087; I2 =99%) P<0.001. There were a limited number of studies (N=16), high variability of design in key study components (sampling frames, included ages, data analyses), and high statistical heterogeneity that could not be explained. Within the limitations of the research, the data show that mean annual attachment level change varies considerably both within and between populations. Overall, the evidence does not support or refute the differentiation between forms of periodontal diseases based upon progression of attachment level change.

Marginal bone loss at implants with different surface characteristics - A 20-year follow-up of a randomized controlled clinical trial.

This report is a 20-year follow-up of a randomized controlled clinical trial evaluating the potential long-term effect of a modified implant surface on the preservation of the peri-implant marginal bone level. In each of 51 patients and for each fixed partial denture (FPD), by randomization at least one implant installed had a non-modified turned surface and one a modified and roughened surface (TiOblast® ). Clinical and radiological examinations were performed at various follow-up intervals. Primary outcome variables were peri-implant marginal bone level change from time of loading and proportion of implants with no bone loss at 20years. Multilevel analysis followed by nonparametric and Pearson's Chi-Square tests were applied for statistical analysis. At the 20-year follow-up, 25 patients carrying 64 implants were available for evaluation. Turned and TiOblast implants presented with a mean bone level change from the time of FDP delivery amounting to -0.41mm (95% CI -0.84/0.02) and -0.83mm (95% CI -1.38/-0.28) respectively (inter-group comparison p>.05). 47% of the Turned and 34% TiOblast implants (p>.05) showed no bone loss. All but one of these implants were free of bacterial plaque and inflammation as well as presented with probing pocket depths ≤5mm at both the 5- and 20-year follow-up examinations. It is suggested that a moderate increase of implant surface roughness has no beneficial effect on long-term preservation of the peri-implant marginal bone level.

Clinical Evidence of OsseoSpeed EV Implants: A Retrospective Study and Characterization of the Newly Introduced System.

This retrospective study sought to compare a new implant (Astra Tech OsseoSpeed EV) with its predecessor (Astra Tech OsseoSpeed TX) by scanning electron microscopy and interferometry. Radiographic data from 19 patients who underwent implant restoration with EV (n = 49) with a median follow-up of 16 months were evaluated for mean bone level (MBL) changes from delivery of the definitive prosthesis. EV and TX did not differ in surface roughness, and both systems had a tight seal at the implant-abutment interface. The median MBL change of the EV was -0.02 mm mesiodistally after a median follow-up period of 16 months. Greater maintenance of MBL was found in the screw-retained restorations (n = 17) compared to cemented (0.35 ± 0.33 mm and -0.38 ± 0.76 mm, respectively; P = .03). The data suggest that EV shows minimal levels of bone loss and high implant survival.

EVALUATION OF MARGINAL BONE LOSS AND PATIENT SATISFACTION IN SINGLE IMPLANT RETAINED MANDIBULAR OVERDENTURE USING TWO DIFFERENT ATTACHMENT DESIGNS

The aim of this study: is to evaluate the marginal bone level changes radiographically and patient satisfaction in immediately loaded single implant retaining mandibular overdenture using two different attachment designs (ball and socket versus telescopic). Materials and Methods: Twenty completely edentulous patients were selected for inclusion in this study. All patients received new maxillary and mandibular dentures. One single para-symphyseal implant was inserted for each patient, immediate loading protocol was done. The patients were divided randomly to have either ball and socket attachment or telescopic attachment. In both groups, radiographic evaluation was done using the standardized long cone peri-apical technique to detect the peri-implant marginal bone level mesial and distal to the implants at two intervals (0-6 months and 0-12 months). Patient satisfaction was evaluated by OHIP-EDENT questionnaire at loading time (baseline), 6 and 12 months after loading. The data obtained were tabulated and statistically analyzed.Results: During the follow-up periods, the marginal bone level around each implant was recorded mesially and distally in both groups (at loading time, after 6 months and after 12 months). .There was no significant difference at the follow-up intervals between the marginal bone loss mesially and distally. There was no statistically significance between the two groups at the 1st and 2nd intervals. Meanwhile, there was a significant difference between the mean bone level change at the 1st interval and the 2nd interval in each group. As the P-Value is 0.000. This means that there is a direct correlation between time and the marginal bone loss. According to the patient satisfaction by OHIP-EDENT questionnaire, there was no significant difference between the two groups. Conclusion: Within the limitations of the present study, the patient satisfaction remained high after treatment with immediately loaded mandibular overdentures supported by one titanium dental implants at the para-symphyseal region in both attachment designs. The telescopic attachment with immediately loaded single implant mandibular overdenture can be a viable and promising treatment option for edentulous patients. It can be as efficient as the ball and socket attachment. Long-term observations and outcomes are needed before recommending it as a treatment modality.

Soft and Hard Tissue Changes Following Immediate Placement or Immediate Restoration of Single-Tooth Implants in the Esthetic Zone: A Systematic Review and Meta-Analysis.

This systematic review aimed to compare immediate protocols with conventional protocols of single-tooth implants in terms of changes in the surrounding hard and soft tissue in the esthetic area. Electronic and manual searches were performed in PubMed, EMBASE, Cochrane, and other data systems for research articles published between January 2001 and December 2014. Only randomized controlled trials (RCTs) reporting on hard and or soft tissue characteristics following a single-tooth implant were included. Based on the protocol used in each study, the included studies were categorized into three groups to assess the relationships between the factors and related esthetic indexes. Variables such as marginal bone level changes (mesial, distal, and mean bone level), peri-implant soft tissue changes (papilla level, midbuccal mucosa, and probing depth), and other esthetic indices were taken into consideration. The data were analyzed using RevMan version 5.3, Stata 12, and GRADEpro 3.6.1 software. A total of 13 RCTs met the inclusion criteria. Four studies examined immediate implant placement, five studies examined immediate implant restoration, and four studies examined immediate loading. Comparing the bone level changes following immediate and conventional restoration, no significant differences were found in the bone level of the mesial site (standard mean difference [SMD] = -0.04 mm; 95% confidence interval [CI]: -0.25 to 0.17 mm), the distal site (SMD = -0.15 mm; 95% CI: -0.38 to 0.09 mm), and the mean bone level changes (SMD = 0.05 mm; 95% CI: -0.18 to 0.27 mm). The difference in the marginal bone level changes between immediate and conventional loading was also not statistically significant (SMD = -0.05 mm; 95% CI: -0.15 to 0.06 mm for the mesial site and SMD = -0.02 mm; 95% CI: -0.09 to 0.05 mm for the distal site). Soft tissue changes following immediate and conventional restoration reported no significant differences in the papillae level of the mesial site (SMD = 0.18 mm; 95% CI: -0.00 to 0.37 mm), the papillae level of the distal site (SMD = -0.12 mm; 95% CI: -0.34 to 0.09 mm), and the midbuccal mucosa (SMD = -0.22 mm; 95% CI: -1.29 to 0.85 mm). Within the limitations, it can be concluded that immediately placed, restored, or loaded single-tooth implants in the esthetic zone result in similar hard and soft tissue changes compared with conventional protocols.

Impact of plasma of argon cleaning treatment on implant abutments in patients with a history of periodontal disease and thin biotype: radiographic results at 24‐month follow‐up of a RCT

A lack of evidence is present in literature regarding the clinical relevance of micropollution and bacterial contamination present on customized titanium abutments following laboratory stages and steaming cleaning procedures. To preserve abutments from such pollutants, plasma of argon cleaning of customized abutments was advocated. The aim of this prospective, randomized, match-paired, triple-blinded, controlled, clinical trial is to longitudinally assess radiographical marginal bone-level changes around implants restored according to the platform switching and "one-abutment-one-time" concepts, using commercially available abutments, with and without plasma of argon cleaning treatment after customization. Thirty patients with thin gingival biotype, a history of periodontal disease, and in general good health received one implant in the anterior maxilla or premolar region. Patients were randomly assigned to control (abutment subjected only to usually adopted cleaning protocol by steam) and test group (abutment subjected to plasma of argon treatment). Periapical standardized digital radiographs were taken at the time of crown connection (T0), 6 (T1) and 24 months after the final restoration (T2). Average mesial-distal bone-level changes mean values with standard deviations (SD) were calculated. The Mann-Whitney U-test was selected to identify differences in bone-level changes between test and control groups. An average interproximal bone loss of 0.16 mm (SD: 0.17) and 0.07 mm (SD: 0.34) was revealed in the control and test group at 6 months (T1), respectively, while after 24 months, groups showed a mean bone-level changes of 0.38 mm (SD: 0.44) and 0.11 mm (SD: 0.14), respectively. Statistically significant differences among control and test groups were found at both time points. Intergroup comparison relived absence of statistically significant difference. Plasma-cleaning treatment of implant titanium abutments, together with platform switching and one-abutment-one-time concepts, could be favorable in terms of hard-tissue-level changes, also in critical conditions such as in patients with a history of periodontal disease, presenting thin gingival biotype.

The Influence of Initial Soft Tissue Thickness on Peri‐Implant Bone Remodeling

To elucidate the influence of initial soft tissue thickness on peri-implant bone remodeling. The research hypothesis was that implants installed in patients or at sites with thin mucosal tissues would show increased peri-implant bone loss. 79 edentulous patients were consecutively treated with two non-splinted implants supporting an overdenture in the mandible. During recall-visits, peri-implant health was determined by means of probing pocket depth and the modified plaque/bleeding index. Digital peri-apical radiographs were taken from individual implants. Bone level changes were measured from a reference point (lower border of the smooth implant collar) to the marginal bone-to-implant contact level. The linear mixed-effect model analysis was adopted to analyze the influence of clinical parameters and transmucosal abutment height on peri-implant bone loss. 67 patients attended the 1-year and 66 the 2-year recall-visit. Mean bone level changes were 0.89 mm (SD 0.62) and 0.90 mm (SD 0.66), plaque scores 0.82 (SD 0.94) and 0.87 (SD 0.92), bleeding scores 0.46 (SD 0.68) and 0.56 (SD 0.72) and PPD 1.65 mm (SD 0.60) and 1.78 mm (SD 0.59) after 1 year and 2 years respectively. The linear mixed-effect model revealed increasing bone level changes with decreasing abutment heights. Peri-implant bone level changes were significantly higher for implants with abutments of <2 mm (1.17 mm, p < .01; 1.23 mm, p < .01), 2 mm (0.86 mm, p < .01; 1.03 mm, p < .01) or 3 mm (0.38 mm, p = .046; 0.41 mm, p = .044) compared to ≥4 mm-abutments (bone level changes set to zero as reference value) both after 1 year and 2 years and bone level changes were significantly influenced by probing pocket depth (p < .01, p < .01), but not by plaque (p = .31, p = .09) and bleeding scores (p = .30, p = .40). The present study suggests that implants with lower abutments, reflecting the initial gingival thickness, lose more peri-implant bone, possibly by a re-establishment of the biological width.

Performance of the Straumann Bone Level Implant system for anterior single‐tooth replacements in augmented and nonaugmented sites: A prospective cohort study with 60 consecutive patients

The purpose of this prospective study was to evaluate radiographic, clinical and aesthetic outcomes and patient satisfaction of cases treated with platform-switched single implant restorations in the aesthetic region of the maxilla. Furthermore, the influence of an augmentation procedure 3months before implant placement and the type of restoration (screw-retained vs. cement-retained) was evaluated. Sixty patients with a missing anterior tooth in the maxilla were treated with a Straumann Bone Level Implant. Bone augmentation was performed in 29 patients at 3months before implant placement. Implants were loaded after 3months of submerged healing. Follow-up was conducted at 7 and 18months after implant placement. Peri-implant mucosa and implant crown aesthetic outcomes were determined using the Implant Crown Aesthetic Index (ICAI) and the Pink Esthetic Score-White Esthetic Score (PES-WES). No implants were lost. At 18months after implant placement, mean bone level change was -0.10±0.27mm and mean probing pocket depth was 2.57mm. No differences were found between augmented and nonaugmented sites (P=0.28). The ICAI indicated satisfactory mucosa and crown aesthetics in 67% and 75% of the cases, respectively, while the PES score was 14.4. ICAI mucosa (P=0.004) and PES (P=0.02) scores were significantly less favourable for augmented sites compared with nonaugmented sites. Patient satisfaction was high (8.9±1.1 on VAS-score). From the present prospective, clinical study, it can be concluded that the Straumann Bone Level Implant shows an excellent survival rate, marginal bone stability and good clinical and aesthetic results. Bone augmentation before implant placement does not lead to more marginal bone loss. However, less favourable pink aesthetic outcomes were found in augmented sites compared with nonaugmented sites, while no differences were found between cement-retained and screw-retained restorations.

Immediate and Early Loading of Chemically Modified Implants in Posterior Jaws: 3‐Year Results from a Prospective Randomized Multicenter Study

There is a lack of well-designed prospective, randomized clinical trials evaluating the efficacy of immediate and early loading of implants placed in the partially edentulous posterior maxilla or mandible. The aim of this study was to evaluate crestal bone level changes over 3 years following immediate or early loading of Straumann implants with a chemically modified surface (SLActive®, Institut Straumann AG, Basel, Switzerland) placed in the posterior maxilla and mandible. Subjects received temporary restorations immediately or 28 to 34 days after surgery, with permanent restorations placed at 20 to 23 weeks. Bone level changes were measured by comparison of standardized radiographs taken on the day of implant placement and 5, 12, 24, and 36 months thereafter. Two hundred thirty-nine of two hundred sixty-six patients (89.9%) completed the trial. Implant survival rates were 97.4% and 96.7% in the immediate and early loading groups, respectively (p = not significant). Over 36 months, the mean bone level change for immediately loaded implants was 0.88 ± 0.81 mm versus 0.57 ± 0.83 mm for the early-loaded group (p < .001). After adjusting for a slight difference in initial placement depth, the time of loading had no significant influence on bone level change. Changes in crestal bone level occurred mostly during the first 5 months postloading. After this bone remodeling period, crestal bone level was stable up to 36 months. Implants with a chemically modified surface are safe and predictable for immediate and early loading in the posterior maxilla and mandible.

Clinical observation of implant immediate loading in periodontitis patients

To evaluate the clinical performance of implants placed immediately after extraction of remaining teeth due to severe periodontitis and immediately loaded for prosthetic oral rehabilitation. Twelve patients in need of complete maxillary or mandibular rehabilitations due to severe periodontitis were enrolled in this study and received periodontal treatment for management of periodontitis. The remaining teeth were extracted, debridement around the periodontally compromised sites was performed. The implants were inserted under guidance by a surgical template, and a prefabricated screwed-retained provisional restoration was immediately delivered on implants. Definitive prostheses were inserted after 6 months. Clinical and radiographic analyses were performed at 1, 6, 12, 24 months. A total of 84 implants were placed, 50 in the maxilla and 34 in the mandible. Thirty-two implants were placed directly in extraction sockets. Four implants in 3 patients failed within the first 6 months, resulting in a total implant survival rate of 95% (80/84). The survival rate was 92% (46/50) in the maxilla, 100% (34/34) in the mandible. Prosthetic success was 100%. All the failures occured in the first 6 months and no failure in the next two years of follow-up. The mean bone level change at 1 and 2 year were (-1.12 ± 0.18) mm and (-1.28 ± 0.14) mm. There were no significant differences in insertion torque and alveolar bone loss between the post-extraction sites and healed sites. The immediate protocols in periodontally compromised maxilla or mandibular contributed to a satisfactory prosthetic success during the 2-year follow-up.

Treatment of peri-implantitis using an Er:YAG laser or an air-abrasive device: a randomized clinical trial

Non-surgical peri-implantitis therapies appear to be ineffective. Limited data suggest that ER:YAG laser therapy improves clinical conditions. The present study aimed at comparing the treatment effects between air-abrasive (AM) and Er:YAG laser (LM) mono-therapy in cases with severe peri-implantitis. Twenty-one subjects in each group were randomly assigned to one time intervention by an air-abrasive device or an Er:YAG laser. Clinical data were collected before treatment and at 6 months. Data analysis was performed using repeat univariate analysis of variance controlling for subject factors. No baseline subject characteristic differences were found. Bleeding on probing and suppuration decreased in both the groups (p<0.001). The mean probing depth (PPD) reductions in the AM and LM groups were 0.9 mm (SD 0.8) and 0.8 mm (SD ± 0.5), with mean bone-level changes (loss) of -0.1 mm (SD ± 0.8) and -0.3 mm (SD ± 0.9), respectively (NS). A positive treatment outcome, PPD reduction ≥0.5 mm and gain or no loss of bone were found in 47% and 44% in the AM and LM groups, respectively. The clinical treatment results were limited and similar between the two methods compared with those in cases with severe peri-implantitis.