Five-year outcomes of a randomized clinical trial comparing bone-level implants with either submerged or transmucosal healing

Is transmucosal healing of an implant as effective as submerged healing when simultaneous guided bone regeneration is performed? A preclinical study

AIM

To investigate whether transmucosal healing is as effective as submerged healing in terms of buccal bone regeneration when guided bone regeneration (GBR) is performed simultaneously with implant placement.

MATERIALS AND METHODS

In six dogs, buccal dehiscence defects were created in the edentulous mandibular ridge, sized 5 × 5 × 3 mm (length × height × depth). In each defect, a bone-level implant was placed, and four experimental groups were randomly assigned as follows: (i) transmucosal healing with GBR (T-GBR), (ii) transmucosal healing without GBR (T-control), (iii) submerged healing with GBR (S-GBR) and (iv) submerged healing without GBR (S-control). Data analyses were based on histological slides 5 months after implant placement.

RESULTS

The T-GBR group showed significant differences compared to the control groups regarding defect height resolution, buccal bone thickness and mineralized tissue area (p < .05), but showed no significant differences when compared with the S-GBR group (p > .05).

CONCLUSIONS

The mode of healing (transmucosal vs. submerged) does not influence bone regeneration at implant sites. The clinician may therefore choose the approach based on further clinical and patient-specific parameters.

The cumulative survival rate of dental implants with micro-threads: a long-term retrospective study

PURPOSE

This study aimed to evaluate the long-term cumulative survival rate (CSR) of dental implants with micro-threads in the neck over a 10-year follow-up period and to examine the factors influencing the survival rate of dental implants.

METHODS

This retrospective study was based on radiographic and dental records. In total, 151 patients received 490 Oneplant® dental implants with an implant neck micro-thread design during 2006-2010 in the Department of Periodontology of Seoul National University Dental Hospital. Implant survival was evaluated using Kaplan-Meier analysis. Cox proportional hazard regression analysis was used to identify the factors influencing implant failure.

RESULTS

Ten out of 490 implants (2.04%) failed due to fixture fracture. The CSR of the implants was 97.9%, and no significant difference was observed in the CSR between external- and internal-implant types (98.2% and 97.6%, respectively, P=0.670). In Cox regression analysis, 2-stage surgery significantly increased the risk of implant failure (hazard ratio: 4.769, P=0.039). There were no significant differences in influencing factors, including sex, age, implant diameter, length, fixture type, location, surgical procedure, bone grafting, and restoration type.

CONCLUSIONS

Within the limitations of this retrospective study, the micro-thread design of the implant neck was found to be favorable for implant survival, with stable clinical outcomes.

Influence of crestal and sub-crestal implant position on development of peri-implant diseases: a 5-year retrospective analysis

OBJECTIVES

The aim of the present study was to evaluate the influence of crestal and subcrestal implant position on development of peri-implant diseases.

MATERIALS AND METHODS

The study was designed as a retrospective clinical and radiographic analysis. Implant-supported fixed dental prostheses were allocated in two groups: with the shoulder (i) placed in sub-crestal level and (ii) placed at bone level. For each patient, the following clinical variables were assessed: FMPS, FMBS, PlI, BOP, and PD. After prothesis delivery, an intraoral radiograph was obtained; this exam was performed also at 5 years of observation period.

RESULTS

No statistically significant difference was found in terms of FMPS and FMBS at baseline and after 5 years follow-up (P < 0.05). A statistically significant difference was assessed between PD of control group and test group (P = 0.042). Patient-based analysis showed a 25.6% of peri-implant mucositis and 32.6% of peri-implantitis for implants placed with the shoulder in crestal position, while for implants inserted in sub-crestal position the percentage of peri-implant-mucositis and peri-implantitis were 19%; no statistically significant difference was found between groups after 5 years (P < 0.05).

CONCLUSIONS

Within the limitation of the present study, the clinical and radiographic outcomes showed that the percentage of peri-implant mucositis and peri-implantitis was not statistically significant for both groups after 5 years follow-up.

CLINICAL RELEVANCE

The outcomes of present study clinically demonstrated that a deep position of implant shoulder did not provide any benefits. On the contrary, it may be considered a possible risk indicator for implant diseases.

Bone regeneration in implant dentistry: Which are the factors affecting the clinical outcome?

The key factors that are needed for bone regeneration to take place include cells (osteoprogenitor and immune-inflammatory cells), a scaffold (blood clot) that facilitates the deposition of the bone matrix, signaling molecules, blood supply, and mechanical stability. However, even when these principles are met, the overall amount of regenerated bone, its stability over time and the incidence of complications may significantly vary. This manuscript provides a critical review on the main local and systemic factors that may have an impact on bone regeneration, trying to focus, whenever possible, on bone regeneration simultaneous to implant placement to treat bone dehiscence/fenestration defects or for bone contouring. In the future, it is likely that bone tissue engineering will change our approach to bone regeneration in implant dentistry by replacing the current biomaterials with osteoinductive scaffolds combined with cells and mechanical/soluble factors and by employing immunomodulatory materials that can both modulate the immune response and control other bone regeneration processes such as osteogenesis, osteoclastogenesis, or inflammation. However, there are currently important knowledge gaps on the biology of osseous formation and on the factors that can influence it that require further investigation. It is recommended that future studies should combine traditional clinical and radiographic assessments with non-invasive imaging and with patient-reported outcome measures. We also envisage that the integration of multi-omics approaches will help uncover the mechanisms responsible for the variability in regenerative outcomes observed in clinical practice.

Tissue-Level Laser-Lok Implants Placed with a Flapless Technique: A 4-Year Clinical Study

BACKGROUND

The present study aims to analyze the use of Laser-Lok microtextured neck implants placed with a transmucosal surgical approach. The marginal bone level (MBL) and periodontal parameters were evaluated in a cohort prospective 4-year clinical study.

METHODS

A total of 41 implants were placed in 36 healthy consecutive patients (16 males, 20 females, mean age 60 ± 9 years). Tapered tissue level implants, characterized by a 2.0 mm laser-microtextured neck, were used with a flapless approach. Customized abutments and provisional resin crowns were positioned. Definitive metal-ceramic crowns were cemented approximately 4 months after insertion. Periapical radiographs were taken after 1, 3, 6, 12, 36 and 48 months from implant placement to evaluate MBL. Gingival thickness (thin/thick), plaque score (PS) and bleeding on probing (BoP) were evaluated.

RESULTS

After 48 months, all implants were safe from complications. No complications, peri-implantitis, early implant failures or mucositis occurred. The survival rate was 100%. Mean MBL during the follow-up was -0.15 ± 0.18 at T1, -0.29 ± 0.29 at T3, -0.45 ± 0.37 at T6, -0.53 ± 0.45 at T12, -1.06 ± 1.13 at T 36 and -1.10 ± 0.89 at T 48. Implants placed 2-3 months after tooth extraction revealed lower MBL variation when compared to those placed immediately (in fresh extraction sockets) or in completely healed ridges (delayed group). Narrower diameter implants (3.8 mm) showed significantly higher MBL variation when compared to 4.6 diameter implants. Multilevel analysis at T48 revealed that among all the evaluated variables, implant diameter was the factor mostly associated with MBL modifications (p = 0.027).

CONCLUSION

This 4-year clinical study supports the use of Laser-Lok implants placed at tissue level with a flapless approach. A limited bone loss during the 48-month follow-up was observed. Periodontal parameters were stable with no sign of inflammation or soft tissue alteration. The use of Laser-Lok implants with transmucosal surgery represents a suitable technique with a minimally invasive approach.

Bone loss-related factors in tissue and bone level dental implants: a systematic review of clinical trials

Dental implants are popular for dental rehabilitation after tooth loss. The goal of this systematic review was to assess bone changes around bone-level and tissue-level implants and the possible causes. Electronic searches of PubMed, Google Scholar, Scopus, and Web of Science, and a hand search limited to English language clinical trials were performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines up to September 2020. Studies that stated the type of implants used, and that reported bone-level changes after insertion met the inclusion criteria. The risk of bias was also evaluated. A total of 38 studies were included. Eighteen studies only used bone-level implants, 10 utilized tissue-level designs and 10 observed bone-level changes in both types of implants. Based on bias assessments, evaluating the risk of bias was not applicable in most studies. There are vast differences in methodologies, follow-ups, and multifactorial characteristics of bone loss around implants, which makes direct comparison impossible. Therefore, further well-structured studies are needed.

Two-Dimensional Analysis of Digital Images through Vector Graphic Editors in Dentistry: New Calibration and Analysis Protocol Based on a Scoping Review

This review was carried out to analyse the functions of three Vector Graphic Editor applications (VGEs) applicable to clinical or research practice, and through this we propose a two-dimensional image analysis protocol in a VGE. We adapted the review method from the PRISMA-ScR protocol. Pubmed, Embase, Web of Science, and Scopus were searched until June 2020 with the following keywords: Vector Graphics Editor, Vector Graphics Editor Dentistry, Adobe Illustrator, Adobe Illustrator Dentistry, Coreldraw, Coreldraw Dentistry, Inkscape, Inkscape Dentistry. The publications found described the functions of the following VGEs: Adobe Illustrator, CorelDRAW, and Inkscape. The possibility of replicating the procedures to perform the VGE functions was analysed using each study’s data. The search yielded 1032 publications. After the selection, 21 articles met the eligibility criteria. They described eight VGE functions: line tracing, landmarks tracing, linear measurement recording, angular measurement recording, image calibration, image overlay, file transfer, and vector graphics development. The features offered by the VGEs bring great precision and objectivity to two-dimensional image analysis. The image analysis and editing procedures are currently not protocolised. Thus, a protocol for image calibration and measurement recording is proposed in order to guarantee the protocol’s replication.

Peri-implant radiographic bone level and associated factors in Spain

OBJECTIVES

To evaluate radiographic bone level (RxBL) at dental implants and its associated factors in Spain.

MATERIAL AND METHODS

This cross-sectional study was performed by a network of sentinel dentists from regions of Spain. RxBL was defined as the distance from the implant shoulder to the first clearly visible contact between the implant surface and the bone. Radiographic measurements were performed by two trained and experienced periodontists. Implant and patient data were also collected. Descriptive, bivariate, discriminative and multivariate analyses were done.

RESULTS

A total of 49 sentinel dentists provided data 275 patients. Mean RxBL from 474 implants (5-13 years) was 1.87 mm (range: 0.00-13.17 mm). Statistically significant associations between RxBL and clinical output variables (bleeding on probing, oedema, plaque, probing depth, suppuration, keratinized tissue) were found. In the multiple regression analysis, statistically significant associations for RxBL were found for smoking habit, implant diameter, years of follow-up and type of prosthesis (p < 0.01).

CONCLUSIONS

Peri-implant RxBL ranged from 0 to 13.17 mm. It was significantly associated with clinical output variables and with some potentially predictor variables, at patient- (smoking >10 cigarettes/day) and implant- (diameter, years of follow-up, Toronto bridge) levels.

Prevalence and risk/protective indicators of buccal soft tissue dehiscence around dental implants

AIM

To evaluate the prevalence of buccal peri-implant soft tissue dehiscence (PISTD) in anterior implants and to identify the risk/protective indicators of PISTD in implants not suffering peri-implantitis.

MATERIALS AND METHODS

240 randomly selected patients from a university clinic database were invited to participate in the present cross-sectional study. Those who accepted, after the evaluation of their medical and dental records, were clinically examined to assess the prevalence of buccal PISTD in non-molar implants. Multilevel multivariate logistic regression analyses were then carried out to identify those factors associated either positively (risk) or negatively (protective) with buccal PISTD in implants without peri-implantitis.

RESULTS

92 patients with a total of 272 dental implants were analysed. At implant-level, the prevalence of buccal PISTD was 16.9%, while when selecting only implants without peri-implantitis it was 12.0%. Buccal PISTD was present in 26.7% of the implants diagnosed with peri-implantitis. The following factors were identified as risk/protective indicators of buccal PISTD in implants without peri-implantitis: malposition (too buccal vs. correct: OR=14.67), thin peri-implant phenotype (OR=8.31), presence of at least one adjacent tooth (OR=0.08) and presence of abutment (OR=0.12).

CONCLUSIONS

PISTD are highly prevalent among patients with dental implants in this university-based population, and several factors were identified as risk and protective indicators of PISTD in implants not suffering peri-implantitis.

Maryland-bridge application as a suitable technique to preserve marginal bone level of not-submerged supracrestal implants

BACKGROUND

One to 6 months after implant placement is a critical time/period responsible for crestal bone loss that may affect implant osseointegration. The study aims to explore the effectiveness of provisional adhesive Maryland-bridge (AMB) applied to prevent marginal bone level (MBL) around implants placed in edentulous crestal bone in posterior area during osseointegration period.

METHODS

Healthy, non-smoker patients (N.=18) were included in the study. Titanium implants were placed nonsubmerged (i.e. tissue-level) with cover screws at gingival level in edentulous crestal bone with flapless technique. Nine patients randomly received an AMB, while 9 patients did not receive any AMB. Each AMB remained in place for 3 months and removed before impression. After 3 months abutments were applied, and provisional resin crowns cemented and definitive metal-ceramic crowns were cemented after 2-3 months. Periapical Rx were taken using paralleling technique before and after implant insertion, at 1, 3 months (pre-loading time) and after 6 months (post-loading time). MBL was evaluated in double-blind on scanned periapical radiographs and assessed at mesial and distal side of implants (M-MBL and D-MBL). Area of bone loss on mesial and distal side of implants (Area-M and Area-D) and Cervical Enamel Junction migration of mesial and distal adjacent teeth were also measured (CEJ-M and CEJ-D). Linear regression models were fitted to evaluate the existence of any significant difference.

RESULTS

Two drop-out was observed in AMB group. A total of 16 patients completed the study. After 6 months, all implants were safe and free from complications. AMB group showed the most stable MBL at 1-6 months, statistically different from non-AMB and resulted in a reduced crestal bone loss from baseline compared to Non AMB group. Area-M and Area-D were not statistically different between the groups. CEJ-M and CEJ-D were stable in both groups.

CONCLUSIONS

The use of Adhesive Maryland Bridge to protect non-submerged post-extractive implants is a safe procedure that prevents bone loss around implants and preserve the 3D architecture of crestal bone ridge.

Prevalence and risk/protective indicators of peri-implant diseases: A university-representative cross-sectional study

AIM

To evaluate the prevalence of peri-implant diseases and to identify risk/protective indicators of peri-implantitis.

MATERIALS AND METHODS

Two hundred and forty randomly selected patients from a university clinic database were invited to participate. Those who accepted, once data from their medical and dental history were collected, were examined clinically and radiographically to assess the prevalence of peri-implant health and diseases. Peri-implantitis was defined as the presence of BoP/SoP together with radiographic bone levels (BL) ≧2 mm. An intermediate peri-implant health category between peri-implant mucositis and peri-implantitis was also identified, defined by the presence of BoP/SoP together with 1 mm ≦BL < 2 mm. A multilevel multivariate logistic regression analysis was carried out to identify those factors associated either positively (risk) or negatively (protective) with peri-implantitis.

RESULTS

Ninety-nine patients with a total of 458 dental implants were analyzed. The prevalences of pre-periimplantitis and of peri-implantitis were, respectively, 31.3% and 56.6% at patient-level, while 31.7% and 27.9% at implant level. The following factors were identified as risk indicators for peri-implantitis: smoking (OR = 3.59; 95% CI: 1.52-8.45), moderate/severe periodontitis (OR = 2.77; 95% CI: 1.20-6.36), <16 remaining teeth (OR = 2.23; 95% CI: 1.05-4.73), plaque (OR = 3.49; 95% CI: 1.13-10.75), implant malposition (too vestibular: OR = 2.85; 95% CI: 1.17-6.93), implant brand (Nobel vs. Straumann: OR = 4.41;95% CI: 1.76-11.09), restoration type (bridge vs. single crown: OR = 2.47; 95% CI: 1.19-5.12), and trauma as reason of tooth loss (vs. caries: OR = 6.51; 95% CI: 1.45-29.26). Conversely, the following factors were identified as protective indicators: interproximal flossing/brushing (OR = 0.27; 95% CI: 0.11-0.68), proton pump inhibitors (OR = 0.08; 95% CI: 0.01-0.90), and anticoagulants (OR = 0.08; 95% CI: 0.01-0.56).

CONCLUSIONS

Peri-implant diseases are highly prevalent among patients with dental implants in this university-based population. Several factors were identified as risk- and protective- indicators of peri-implantitis.

Clinical signs, symptoms, perceptions, and impact on quality of life in patients suffering from peri-implant diseases: a university-representative cross-sectional study

OBJECTIVES

To study the symptoms and perception reported by patients with peri-implant diseases, as well as their signs and their potential impact on the oral health quality of life.

MATERIAL AND METHODS

Two hundred and forty randomly selected patients were invited to participate. As part of the history assessment, the patient OHIP-14Sp was evaluated together with, for each implant, the patient perception regarding the peri-implant health status and the history of pain, spontaneous discomfort, bleeding, suppuration, swelling, and discomfort during brushing. As part of the clinical examination, the following potential signs of peri-implant diseases were collected: probing pocket depth (PPD), mucosal dehiscence (MD), extent of BoP, presence of SoP, and visual signs of redness and swelling. Those parameters were analyzed in relation to the actual peri-implant health diagnosis.

RESULTS

Ninety-nine patients with a total of 458 dental implants were studied. Even in case of peri-implantitis, 88.9% of the implants were perceived by the patients as healthy. The total OHIP-14Sp sum score did not differ in relation to the peri-implant health diagnosis. Increased reports of spontaneous discomfort, bleeding, swelling, and discomfort during brushing were observed in presence of disease. However, only a minor proportion of implants with peri-implant diseases presented symptoms. PPD ≥ 6 mm was more frequent in diseased than in healthy implants (p < .01), while PPD ≥ 8 in pre-peri-implantitis/peri-implantitis than in healthy/mucositis implants (p < .01). Implants with peri-implantitis showed higher MD than implants without peri-implantitis (p < .01).

CONCLUSION

Peri-implant diseases are in most cases asymptomatic and not perceived by the patients. Despite being unable to accurately discriminate between peri-implant mucositis and peri-implantitis, PPD and MD resulted as the only two clinical signs associated with pre-peri-implantitis/peri-implantitis.

Differences in the progression of experimental peri-implantitis depending on the implant to abutment connection

OBJECTIVES

The aim was to evaluate the rate of bone loss progression during experimentally induced peri-implantitis using two different implant-abutment connections in implants with identical surface topography.

MATERIAL AND METHODS

Forty-eight Regular Neck tissue-level SLA implants with a matching implant to abutment connection (TL) and 36 bone-level SLA implants with a switching platform implant to abutment connection (BL) were subjected to experimental peri-implantitis in two independent in vivo pre-clinical investigations. Experimental peri-implantitis was induced by means of silk ligatures during 3 months (induction phase), and followed for one extra month without ligatures (progression phase). Radiographic and clinical outcomes were evaluated longitudinally along both studies and subsequently compared between experiments.

RESULTS

During the induction phase, radiographic bone loss was significantly higher in implants with matched abutments compared with those with platform switching connections (2.65 ± 0.66 mm vs 0.84 ± 0.16 mm, respectively, p = 0.001). During the progression phase, both types of implant-abutment connection exhibited similar rates of radiographic bone loss. Similar outcomes were observed clinically.

CONCLUSIONS

A platform switching connection resulted in a more benign development of peri-implantitis during the experimental induction phase of the disease. These differences, however, disappeared once the ligatures were removed (progression phase).

CLINICAL RELEVANCE

Influence of the implant-abutment connection in peri-implantitis progression may be relevant when considering implant selection in the moment of placement. In this sense, platform switching abutment demonstrated less peri-implantitis development when compared to implant matching connection.

Clinical and patient-reported outcome of implant restorations with internal conical connection in daily dental practices: prospective observational multicenter trial with up to 7-year follow-up

Background

The interpretation of the results of randomized clinical trials is often questioned in relation with daily circumstances in practices. This prospective observational multicenter study was instigated to reflect the need for information in real-life situations with dental implants with internal conical implant-abutment connection (Conelog implant system). The implants were followed up at least 5-year post-loading; survival analysis (Kaplan-Meier), changes of soft tissue, and bone level over time, as well as patient satisfaction were evaluated.

Results

In total, 130 dental implants were placed in 94 patients (64 female, 30 male). Mean age of patients was 50.4 ± 13.7. At 5-year post-loading, 104 implants in 76 patients were available for evaluation. The cumulative implant survival rate was 96.6%. After an initial bone remodeling process post-surgery (bone loss of − 0.52 ± 0.55 mm), the bone level change remained clinically stable from loading to 5-year post-loading (− 0.09 ± 0.43 mm). Patient satisfaction surveyed by questionnaire (comfort, ability to chew and taste, esthetics, general satisfaction) steadily increased towards the end. At the last study follow-up, all the patients rated their general satisfaction as either very satisfied (87.5%) or satisfied (12.5%).

Conclusion

The study implants have shown to be highly effective with reliable peri-implant tissue stability over the 5 to 7 years of observation for both single tooth restorations and fixed partial dentures while used in standard conditions in daily dental practice. The results obtained are comparable with those obtained in controlled clinical trials.

Clinical and radiographics results at 3 years of RCT with split-mouth design of submerged vs. nonsubmerged single laser-microgrooved implants in posterior areas

Aim

To evaluate and compare radiographic crestal bone loss (CBL) and soft tissue parameters around submerged/two-stage and nonsubmerged/one-stage single implants with the same endosseous portion (body design and surface, thread design and distance) and identical intramucosal laser-microgrooved surface, after 3 years of loading.

Materials and methods

Twenty submerged/two-stage implants and 20 nonsubmerged/one-stage implants were placed randomly with a split-mouth design in the posterior areas of 20 partially edentulous patients.

Radiographic and clinical examinations were carried out at the implant placement, at the delivery of prosthetic restorations, and at each year of the follow-up period. Plaque index (PI), probing depth (PD), bleeding on probing (BOP), and gingival recession (REC) were recorded. Radiographic crestal bone levels were assessed at the mesial and distal aspect of the implant sites. In addition, the influence of the vertical keratinized tissue thickness (KTT) on CBL was investigated.

Results

At the delivery of prosthetic restorations, a statistically significant difference (P = 0.013) was found in radiographic mean CBL between submerged and nonsubmerged implants (0.15 ± 0.05 mm vs. 0.11 ± 0.04 mm). At the end of the follow-up period, no statistical difference (P = 0.741) was found in the mean CBL between submerged and nonsubmerged implants (0.27 ± 04 mm vs. 0.26 ± 0.5 mm). The changes in the soft tissues including PI, PD, BOP, and REC had no significant differences in either group. Moreover, KTT did not show a statistical correlation with CBL.

Conclusions

After 3 years of loading, no statistical difference was noted in CBL and soft tissue conditions between single submerged two-stage and nonsubmerged one-stage laser-microgrooved implants.

Trial registration

http://clinicaltrials.gov/ct2/show/NCT03674762

The Effect of Tapered Abutments on Marginal Bone Level: A Retrospective Cohort Study

Background: Early peri-implant bone loss has been associated to long-term implant-prosthetic failure. Different technical, surgical, and prosthetic techniques have been introduced to enhance the clinical outcome of dental implants in terms of crestal bone preservation. The aim of the present cohort study was to observe the mean marginal bone level around two-part implants with gingivally tapered abutments one year after loading. Methods: Mean marginal bone levels and change were computed following radiological calibration and linear measurement on standardized radiographs. Results: Twenty patients who met the inclusion criterion of having at least one implant with the tapered prosthetic connection were included in the study. The cumulative implant success rate was 100%, the average bone loss was −0.18 ± 0.72 mm, with the final bone level sitting above the implant platform most of the time (+1.16 ± 0.91 mm). Conclusion: The results of this cohort study suggested that implants with tapered abutments perform successfully one year after loading and that they are associated with excellent marginal bone preservation, thus suggesting that implant-connection macro-geometry might have a crucial role in dictating peri-implant bone levels.

Peri-implant marginal bone loss rate pre- and post-loading: An exploratory analysis of associated factors

OBJECTIVES

To perform an exploratory analysis of factors influencing annual rates of peri-implant marginal bone loss (RBL) calculated over different time frames, at implants unaffected by peri-implantitis.

MATERIAL AND METHODS

A total of 154 implants from 86 patients were reviewed at 1.6-6.8 years after placement. Marginal bone levels (MBL) were assessed on intraoral radiographs at three time-points: immediately post-placement, time of loading, and least 1-year post-loading. RBLs (mm/year) were computed using these three time frames and corresponding MBL changes as: RBL placement-loading, RBL loading-review, RBL placement-review. Exploratory ordination of three RBLs, corresponding time durations, and 17 background factors were used for visualization. Hierarchical linear mixed-effects models (MEM) with predictor selection were applied to RBL outcomes. The correlation of actual MBL with MBLs predicted by RBL placement-loading and RBL loading-review was tested.

RESULTS

Median RBL placement-loading was 0.9 mm/year (IQR = 2.02), loading-review was 0.06 mm/year (IQR = 0.16), and overall RBL placement-review was 0.21 mm/year (IQR = 0.33). Among-patient variance was highest for RBL placement-loading (SD = 0.66). Longer time predicted lower RBL in all time frames. Shorter time of loading significantly predicted lower RBL placement-review. Augmentation predicted lower RBL placement-loading, while anterior location and older age predicted lower RBLs placement-loading placement-review. Only MBL projected using RBL placement-loading significantly correlated with actual MBL.

CONCLUSIONS

Exploratory analysis indicated RBL varied with the time duration used for calculation in pre- and post-loading, and overall periods. In each period, RBL declined with increasing time. Earlier loading predicted lower overall RBL. Higher pre-loading RBL predicted worse actual bone level.