Marginal bone loss 1 year after implantation: a systematic review for fixed and removable restorations

Changes in Peri-implant Marginal Bone Level by Jaw Location: A Systematic Review and Meta-Analysis of 4970 Implants

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

Bone remodeling around dental implants after 1-1.5 years of functional loading: A retrospective analysis of two-stage implants

OBJECTIVES

This study aims to retrospectively assess to what extent peri-implant bone level changes occur from exposing the implant to the oral environment at the second stage of surgery (SSS) to the baseline assessment and, additionally, after 1-1.5 years of functional loading. Further, this study aims to examine the role of the emergence angle in marginal bone changes.

MATERIAL AND METHODS

This retrospective study included 46 patients treated between 2012 and 2019. These patients received 64 bone-level dental implants. After implant placement, SSS, and baseline assessment, relevant clinical peri-implant conditions and radiographical data were collected. A radiographic examination of the marginal bone level was performed after SSS, the baseline assessment, and 1-1.5 years of follow-up.

RESULTS

The peri-implant periodontal probing depth increased significantly from 3.08 ± 0.7 mm at the baseline to 3.27 ± 0.81 mm at the 1-1.5-year follow-up. The mean marginal bone level at the implant level was 0.12 ± 0.23, 0.35 ± 0.43, and 0.47 ± 0.47 mm at the SSS, baseline, and the 1-1.5-year follow-up, respectively. Most changes occurred at the implant's distal site. A significant relationship was found between the emergence angle and the extent of change in the marginal bone level between the SSS and baseline (r = .430, p ≤ .001).

CONCLUSIONS

Most changes in the marginal bone level occurred between SSS and baseline assessments. For diagnostic purposes, it is advised to obtain a standardized radiograph after SSS to monitor peri-implant bone-level alterations.

Marginal Bone Loss around Implant-Retaining Overdentures versus Implant-Supported Fixed Prostheses 12-Month Follow-Up: A Retrospective Study

Few studies have compared marginal bone loss (MBL) around implant-retaining overdentures (IODs) vs. implant-supported fixed prostheses (FPs). This study evaluated the mean MBL and radiographic bone-implant interface contact (r-BIIC) around IODs and implant-supported FPs. We also investigated osseointegration and MBL around non-submerged dental implants. We measured the changes between the MBL in the mesial and distal sites immediately after prosthetic delivery and after one year. The mean MBL and its changes in the IOD group were significantly higher. The mean percentage of r-BIIC was significantly higher in the FP group. MBL and its changes in males were significantly higher in the IOD group. The percentage of r-BIIC was significantly higher in the FP group. MBL in the lower site in the IOD group was significantly higher. Regarding MBL, the location of the implant was the only significant factor in the IOD group, while gender was the only significant predictor in the FP group. Regarding the r-BIIC percentage, gender was a significant factor in the FP group. We concluded that non-submerged dental implants restored with FPs and IODs maintained stable bone remodeling one year after prosthetic delivery.

[Clinical observation of the curative effect after 5-year follow-up of single tooth implant-supported restorations in the posterior region]

OBJECTIVE

To analyze the clinical curative effect after 5-year follow-up of single tooth implant-supported restorations in the posterior region.

METHODS

In the study, patients with single tooth implant-supported restorations in the posterior region after loading 5-year in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2005 to May 2010 was enrolled. The implant survival rate, prosthetic conditions (including the structural integrity or loosening of the prosthesis, the retention of the materials used to fill access holes of screw-retained implant crowns, loosening or fractures of the implant abutment or screw) and marginal bone lever level around implants were determined by clinical and radiographic examination.

RESULTS

The study was composed of 215 patients, the mean age was 48.6 years (range: 27 to 71), and 321 soft tissue implants were inserted. There were 9 implants loose and lost during the visit, the cumulative success rate was 97.2%. In the 312 remaining implants, 120 implants were placed in the upper jaws (38.5%) and 192 in the lower jaws (61.5%). Three different diameters as 3.3 mm (5 implants), 4.1 mm (115 implants) and 4.8 mm (192 implants) and three different lengths as 8 mm (21 implants), 10 mm (206 implants) and 12 mm (85 implants) were used, respectively. 277 (88.8%) cement-retained and 35 (11.2%) screw-retained implant-supported single crowns were made. The marginal bone loss (MBL) around dental implants after loading 5 years in the mesial and distal sides were (0.73±0.25) mm and (0.78±0.26) mm, respectively. There was no significant difference among MBL and bone quality, implant type, angle of abutment, prosthodontic type, crown-to-implant ratio, gender, and age of the patients (P > 0.05). The major mechanical complications after restoration involved loosening (8.6%) and fracture (2.9%) of the crown retainer screw, loss of resin covering the screw (11.4%), and the most frequent mechanical complications were loss of crown retention (14.1%) and fracture of porcelain (13.8%). The incidence of loss of crown retention was correlated with insufficient clinical crown height or using angle abutment (P < 0.05).

CONCLUSION

After loading 5 years, the bone level around the soft-tissue-implant placed in posterior region was stable. To minimize the frequency of mechanical complications after restoration, protocols must be established from diagnosis to the completion of treatment and follow up of implant-supported prostheses, especially in terms of adequate technical steps and careful radiographic evaluation of the components.

[Clinical observation of the curative effect after 5-year follow-up of single tooth implant-supported restorations in the posterior region]

OBJECTIVE

To analyze the clinical curative effect after 5-year follow-up of single tooth implant-supported restorations in the posterior region.

METHODS

In the study, patients with single tooth implant-supported restorations in the posterior region after loading 5-year in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2005 to May 2010 was enrolled. The implant survival rate, prosthetic conditions (including the structural integrity or loosening of the prosthesis, the retention of the materials used to fill access holes of screw-retained implant crowns, loosening or fractures of the implant abutment or screw) and marginal bone lever level around implants were determined by clinical and radiographic examination.

RESULTS

The study was composed of 215 patients, the mean age was 48.6 years (range: 27 to 71), and 321 soft tissue implants were inserted. There were 9 implants loose and lost during the visit, the cumulative success rate was 97.2%. In the 312 remaining implants, 120 implants were placed in the upper jaws (38.5%) and 192 in the lower jaws (61.5%). Three different diameters as 3.3 mm (5 implants), 4.1 mm (115 implants) and 4.8 mm (192 implants) and three different lengths as 8 mm (21 implants), 10 mm (206 implants) and 12 mm (85 implants) were used, respectively. 277 (88.8%) cement-retained and 35 (11.2%) screw-retained implant-supported single crowns were made. The marginal bone loss (MBL) around dental implants after loading 5 years in the mesial and distal sides were (0.73±0.25) mm and (0.78±0.26) mm, respectively. There was no significant difference among MBL and bone quality, implant type, angle of abutment, prosthodontic type, crown-to-implant ratio, gender, and age of the patients (P > 0.05). The major mechanical complications after restoration involved loosening (8.6%) and fracture (2.9%) of the crown retainer screw, loss of resin covering the screw (11.4%), and the most frequent mechanical complications were loss of crown retention (14.1%) and fracture of porcelain (13.8%). The incidence of loss of crown retention was correlated with insufficient clinical crown height or using angle abutment (P < 0.05).

CONCLUSION

After loading 5 years, the bone level around the soft-tissue-implant placed in posterior region was stable. To minimize the frequency of mechanical complications after restoration, protocols must be established from diagnosis to the completion of treatment and follow up of implant-supported prostheses, especially in terms of adequate technical steps and careful radiographic evaluation of the components.

Clinical Performance of Implant Crown Retained Removable Partial Dentures for Mandibular Edentulism-A Retrospective Study

The studies on implant-crown-retained removable partial dentures (IC-RPDs) for edentulism are scarce. The purpose of this study was to evaluate survival rates and marginal bone loss (MBL) of IC-RPDs compared to implant overdentures (IODs) in mandibular edentulism. Variables that influenced survival and marginal bone loss (MBL) of implants in both treatment modalities were analyzed and the functional/esthetic satisfaction of patients as well as prosthetic complications were also observed. Eighteen IC-RPDs with a total of 60 implant-supported survey crowns and 24 IODs with a total 94 implants retained with magnet attachments were observed. After a median observation period of 46.6 months (up to 149 months), we observed 98.3% implant survival rates for IC-RPDs and 92.5% for IODs. Kaplan–Meier survival curves based on the treatment modality showed that, at 96 months, cumulative survival rates were 98.3% in IC-RPD and 83.1% in IOD. For implant survival rates, no statistical differences were observed according to age, sex, opposing dentition, or implant positions (p = 0.515, 0.666, 0.201, 0.749, respectively). The implant MBL measurements for IC-RPD and IOD groups at the final recall check were 0.93 ± 1.22 mm and 2.12 ± 2.09 mm, respectively. Additionally, there were no significant differences between groups (p = 0.554). The implants with peri-implantitis at year 1 showed significantly higher MBL at final check-up (p < 0.001). The MBL of implants showed significant differences based on age (p = 0.008) and opposing dentition (p = 0.003). No significant differences of implant MBL were observed for the position of placed implants (p = 0.621) or sex (p = 0.666). Patient-reported outcome measures (PROMs) on functional and esthetic satisfaction were significantly improved after IC-RPD or IOD treatment (p < 0.001). The most frequent prosthetic complication of IC-RPD was clasp loosening, while for IOD group, it was attachment dislodgement. Within the limitations of this retrospective study, we concluded that IC-RPDs could be considered as a viable treatment option for edentulous patients who need few fixed abutments for satisfaction.

Use of a Novel In Situ Hardening Biphasic Alloplastic Bone Grafting Material for Guided Bone Regeneration around Dental Implants - A Prospective Case Series

INTRODUCTION

The novel bioresorbable polymer poly (lactide-co-glycolic acid) (PLGA) coated biphasic calcium phosphate material (BCP) hardens into a stable and porous hard tissue scaffold when exposed to body fluids. The self-containable, stable bone graft material might be beneficial for facilitating guided bone regeneration (GBR) around dental implants, especially for a defect with an absence of bony wall(s). The aim of this prospective case series is to evaluate the post-surgical implant survival and success where the in situ hardening BCP was used for GBR around dental implants.

CASE SERIES

Ten patients received 13 implants with simultaneous bone augmentation. Dehiscence and/or fenestration type of bony defect was detected in nine surgical sites, and three surgical sites exhibited a suprabony defect. In nine out of the 13 implants, a membrane was used in conjunction with the bone grafting. Patients were evaluated at the day of the surgery as well as 2 weeks, and 1, 3, 6, and 12 months postoperatively. All post-surgical wounds were uneventfully healed. Radiographic bone levels showed stability over time with an average bone loss/remodeling of 0.19 ± 0.6 mm (range, -0.5-1.5 mm) from implant placement to the last follow-up at 12 months. All implants survived after 12 months.

CONCLUSIONS

Implant placement with simultaneous bone grafting using the in situ hardening BCP, was shown to be a viable and safe procedure with stable clinical and radiographic results over the follow-up period. Further long-term studies are warranted, however, the combination of the ease of handling and the favorable results are promising.

Marginal bone loss around oral implants supporting fixed versus removable prostheses: a systematic review

Aim

The aim of this systematic review was to evaluate and compare the marginal bone loss (MBL) around implants of fixed (FISP) versus removable implant-supported prosthesis (RISP).

Material and methods

This review was conducted according to the PRISMA guidelines. A systematic search of the literature on Web of Science and Ovid (MEDLINE) was conducted in March 2019 to identify randomized controlled trials/quasi-randomized trials, prospective and retrospective studies written in German and English. Two reviewers screened the identified papers for eligibility and performed an independent data extraction. The Newcastle-Ottawa Scale was used to evaluate the level of evidence of the included studies.

Results

The search resulted in 2577 studies, of which 42 were selected for full-text evaluation. Finally, six studies were included in qualitative analyses, reporting results from 248 participants (81 FISP versus 167 RISP). Five of the included studies were prospective and one study was retrospective. MBL was highest in the first year after implant placement and ranged from 0.17 ± 0.07 mm to 2.1 ± 1.6 mm in FISP and from 0.22 ± 0.55 mm to 2.5 ± 2.7 mm in RISP. After 4 years, there was no statistically significant difference between the groups; MBL ranged from 0.36 ± 0.22 mm to 1.5 mm in FISP and 0.56 ± 0.45 mm to 1.4 mm in RISP. Of the six included studies, two each were rated as good quality, fair quality, and poor quality.

Conclusion

Fixed and removable implant-supported prostheses seem to have similar long-term outcomes regarding marginal bone loss. However, the evidence provided in this systematic review is limited due to the poor quality of two of the included studies. Future studies with study designs specified to the topic of this review are necessary to provide clear information about marginal bone level alterations in modern implant therapy.