Evaluation of aesthetics of implant-supported single-tooth replacements using different bone augmentation procedures: a prospective randomized clinical study

OBJECTIVES: The aim of this study was to evaluate the aesthetics of implant-supported single-tooth replacements using different augmentation procedures in a prospective study with the use of an objective rating index and with a subjective patient questionnaire, and to compare the results with each other. MATERIAL AND METHODS: Ninety-three patients with a single-tooth gap in the anterior zone of the maxilla were selected for the study. All patients had a local bone defect that needed augmentation before placement of an endosseous implant with sufficient initial stability. Aesthetics of the implant-supported crown and adjacent mucosa was rated by a prosthodontist 1 year after placement of the porcelain crown. Aesthetics was rated using the Implant Crown Aesthetic Index. A subjective appreciation of the final result was assessed with a patient questionnaire. RESULTS: The Implant Crown Aesthetic Index reveals a mean overall score of 4.8, with an acceptable result in 66% of the cases. Results of the satisfaction questionnaire reveal a mean overall score of 8.5 with an acceptable result in 100% of the cases. There is no correlation between results of the Index and the questionnaire for the overall and the crown score. The patients' opinion and the professionals' opinion about the peri-implant mucosa do show a significant correlation. CONCLUSIONS: The peri-implant mucosa is rated as less satisfactory than the implant-supported crown by both the dental professional and patients. The dental professional was less satisfied with respect to the total result and results of the crown than the patients.     

Autogenous bone graft alone or associated with titanium mesh for vertical alveolar ridge augmentation: a controlled clinical trial

OBJECTIVES: The aim of this controlled clinical trial is to evaluate alveolar ridge augmentation using an autogenous onlay bone graft alone or associated with a titanium mesh (Ti-Mesh). MATERIAL AND METHODS: A group of 23 partially edentulous patients, presenting the need for vertical bone augmentation of at least 4 mm, were treated before implant placement. Surgical procedure was performed by the same operator and was identical at 12 test (bone graft+Ti-Mesh) and 12 control (bone graft alone) sites. During the first surgery, an autogenous bone graft was harvested from the mandibular ramus and secured by means of titanium screws. Particulate bone was added. In patients assigned to the test group only, a Ti-Mesh was used to stabilize and protect the graft. RESULTS: No major complications were recorded at recipient or donor sites. After a mean interval of 4.6 (SD 0.7) months, the mean vertical augmentation obtained was 5 mm (range 4-7 mm) for the test group and 3.4 mm (range 3-6 mm) for the control. The sites with Ti-Mesh coverage underwent bone resorption of 13.5%, while the sites with no coverage showed a corresponding value of 34.5%. The differences between the two groups were statistically significant. Implants were placed at all grafted sites. CONCLUSION: The results of this study suggest that an onlay osseous graft protected by a Ti-Mesh demonstrated significantly less bone resorption when compared with an onlay bone graft alone. This benefit was reduced in case of short-term mesh exposure, with limited drawbacks.     

Comparison of two different surgical approaches to increase peri‐implant mucosal thickness: A randomized controlled clinical trial

1 Background

Current evidence supports the positive effect of adequate peri‐implant mucosal thickness (PMT) on both marginal bone level stability and esthetic outcomes. While the subepithelial connective tissue graft (sCTG) has been traditionally considered as the gold standard for peri‐implant mucosal augmentation, acellular dermal matrix (ADM) may be a valid alternative. The primary aim of this randomized clinical trial was to determine the clinical efficacy of ADM in the augmentation of PMT as compared to an autologous sCTG.

2 Methods

Patients who could benefit from peri‐implant mucosal augmentation at the time of implant placement were recruited. Participants were randomized to the control (simultaneous sCTG) or test (simultaneous ADM) group. The primary outcome in this study was changes in PMT between baseline and 16 weeks later. Keratinized mucosal width (KMW) changes, modified wound healing index (MWHI) variations and patient‐reported outcome measures (PROMs) were recorded, as well.

3 Results

A total of 20 participants were recruited per an a priori power analysis. There were no statistically significant differences between groups at baseline for any of the parameters analyzed. The gain in PMT at 1 mm, 3 mm, and 5 mm from the expected mucosal margin was 0.44 ± 2.04 mm, 1.20 ± 1.48 mm, and 1.20 ± 0.89 mm in the sCTG group, and 0.05 ± 1.57 mm, 0.85 ± 1.29 mm, and 1.45 ± 1.17 mm in the ADM group. No statistically significant differences in terms of PMT, KMW, and MWHI changes were observed between groups. The perceived discomfort was higher at 2 and 4 weeks for patients in the sCTG group.

4 Conclusion

ADM produces similar outcomes to sCTG in terms of mucosal augmentation at the time of implant placement.     

Esthetic outcomes with porcelain-fused-to-ceramic and all-ceramic single-implant crowns: a randomized clinical trial

Objectives: The aim of this randomized‐controlled clinical trial was to compare the objective and subjective esthetic outcomes of two types of screwed‐retained single‐implant crowns. Materials and methods: Participants were randomly assigned to the test (all‐ceramic) and control [porcelain‐fused‐to‐ceramic (PFM)] groups and were seen under investigation at baseline (B), crown insertion (CI), 1‐year follow‐up (1Y), and 2‐year follow‐up (2Y). Objective parameters were assessed by an intra‐oral digital photograph (1 : 1 ratio), a study cast, a standardized radiograph, periodontal/peri‐implant measurements, and questionnaires were obtained for the subjective parameters. In addition, pink esthetic score (PES) and white esthetic score (WES) were calculated for both groups. For the subjective evaluation, a visual analogue scale (VAS) questionnaire was used to assess the level of patient satisfaction regarding the esthetic outcome. Then, nine expert clinicians visually inspected and assessed subjective evaluation at the professional level. Statistical analysis was used to compare between groups and investigational appointments. Results: Twenty patients were included in the study, 10 allocated to the all‐ceramic group and 10 to the PFM group. No statistically significant differences were observed for the objective measurements comparing the test and control groups. Minor chipping of the ceramic veneering material was observed in the two patients of control group. The mean difference for all groups comparing objective parameters revealed an increase of papilla height between time points. A slight recession (0.26 mm) of the peri‐implant mucosal margin at the implant site was observed between 1Y and 2Y. Mean values for PES and WES were 13.9 and 13.1 for the PFM group and for the all‐ceramic group, respectively. These values were not statistically significant. Implant crown volume, outline, translucency, and characterization showed major discrepancies with the contra‐lateral natural teeth. As for subjective parameters, VAS patients' responses regarding their perceptions of the esthetic outcome showed no statistical differences betwen groups and clinicians' accuracy scores were 50% and 47% for PFM and all‐ceramic crowns, respectively. Conclusion: PFM and all‐ceramic single‐implant restorations may be indistinguishable from each other regarding the objective/subjective assessment of esthetic integration. The material chosen for fabricating an implant crown per se does not ensure an optimal esthetic outcome if other esthetic parameters are not present. To cite this article:
Gallucci GO, Grütter L, Nedir R, Bischof M, Belser UC. Esthetic outcomes with porcelain‐fused‐to‐ceramic and all‐ceramic single‐implant crowns: a randomized clinical trial.
Clin. Oral Impl. Res. 22 , 2011; 62–69.
doi: 10.1111/j.1600‐0501.2010.01997.x     

The influence of different soft‐tissue grafting procedures at single implant placement on esthetics: A randomized controlled trial

1 Background

Soft‐tissue grafting to thicken the soft tissue around dental implants was proposed to ameliorate the esthetic outcome. Traditionally, connective tissue is used as a grafting material, but a xenogeneic collagen matrix was introduced as an alternative to reduce patient morbidity.

2 Methods

A total of 60 patients randomly received either no graft (n = 20, NG group), a connective tissue graft (n = 20, CTG group), or a xenogeneic collagen matrix (n = 20, XCM group) when an implant was placed in a preserved alveolar ridge. Changes in mid‐buccal mucosal level (MBML) at 1 (T₁) and 12 (T₁₂) months after final implant crown placement were compared to the pre‐extraction level. Additionally, esthetics, marginal bone level, clinical peri‐implant parameters, and patient satisfaction were assessed.

3 Results

At T₁₂, mean changes in MBML were –0.48 ± 1.5 mm, –0.04 ± 1.1 mm, and –0.17 ± 1.3 mm in the NG, CTG, and XCM groups (P = 0.56), respectively. Regarding the other outcome variables, no significant intergroup differences were observed.

4 Conclusions

Soft‐tissue grafting at single implant placement in preserved alveolar ridges does not result in a better esthetic outcome or in better peri‐implant health and should not be considered as a standard procedure.