Peri‐implant soft tissue and bone crest alterations at fixed dental prostheses: a 3‐year prospective study

Objectives: The aim of this 3‐year prospective study involving patients receiving implant‐supported fixed dental prostheses (FDPs) was to longitudinally evaluate soft and hard tissue alterations from the time of implant placement. Material and methods: Sixteen subjects with 18 implant‐supported FDPs on 43 implants were included in the study. Peri‐implant soft and hard tissue assessments were performed at implant placement, 2, 6, 12, 24 and 36 months. Variables describing the peri‐implant soft tissue conditions and topography were assessed by clinical, photographic and study model assessments. Variables of implant position and bone topography were measured in radiographs taken at each examination interval. Multilevel regression models were formulated to identify factors of significance for proximal bone crest alterations and proximal soft tissue height. Results: During the first 6 months after the one‐stage implant placement surgery, the soft tissue margin receded about 0.6 mm at facial implant sites, while a mean increase was observed at tooth‐facing proximal sites (1.1 mm) and no change at inter‐implant sites. Loss in proximal bone crest height was more pronounced at inter‐implant than tooth–implant units at 6 months (0.6 vs. 0.1 mm). Between 6 and 36 months, no further significant soft or hard tissue changes were observed. Multilevel regression analysis revealed that the proximal bone crest level significantly influenced the proximal soft tissue height assessed from the implant/abutment level. Significant predictors for loss in proximal bone crest level over the 3 years were horizontal inter‐unit distance, type of proximal unit (tooth/implant or inter‐implant) and peri‐implant bone‐level change. Conclusions: Soft and hard tissue changes around implant‐supported FDPs took place primarily during the first 6 months after the one‐stage implant installation surgery. The pattern of tissue alterations during the follow‐up differed between tooth–implant and inter‐implant proximal sites. To cite this article:
Chang M, Wennström JL. Peri‐implant soft tissue and bone crest alterations at fixed dental prostheses: a 3‐year prospective study.
Clin. Oral Impl. Res. 21, 2010; 527–534.
doi: 10.1111/j.1600‐0501.2009.01874.x     

Mandibular complete denture versus single‐implant overdenture: a systematic review of patient‐reported outcomes

The single‐implant mandibular overdenture (SIMO) has been proposed as an alternative for edentulous patients who are poorly adapted to their dentures due to low retention and stability of the conventional mandibular complete denture (CD). However, there is a lack of evidence regarding the effectiveness of SIMO, which can be measured by examining patient perception of treatment effects. The aim of this systematic review was to assess the comparative results of CD and SIMO treatments using patient‐reported outcome measures. A literature search was carried out in PubMed, Scopus and Cochrane Central databases. The search included studies published up to July 2017. The focus question was: ‘Do single‐implant mandibular overdentures improve patient‐reported outcomes compared to conventional complete dentures in edentulous patients?’ Eligible studies were randomised clinical trials (RCT) and prospective studies. After initial screening for eligibility and full‐text analysis, 11 studies were included for data extraction and quality assessment (five parallel‐group RCTs, two crossover RCTs and four prospective studies). All studies reported marked improvement in satisfaction with the dentures and quality of life measures after SIMO treatment, irrespective of variations in implant treatment protocols and retention systems. Methodological considerations revealed a lack of evidence from RCTs on the comparative effectiveness of the two treatment strategies. Hence, although available evidence suggests considerable improvement in patient‐reported outcomes following the insertion of a single implant to retain a mandibular denture, further well‐designed comparative studies between SIMO and CD are required to improve the level of evidence and to support the indication of SIMO treatment in routine practice.     

Effects of modified abutment characteristics on peri‐implant soft tissue health: A systematic review and meta‐analysis

Objectives

The purpose of this systematic review was to evaluate the impact of the abutment characteristics on peri‐implant tissue health and to identify the most suitable material and surface characteristics.

Methods

A protocol was developed aimed to answer the following focused question: “Which is the effect of the modification of the abutment design in regard to the maintenance of the peri‐implant soft tissue health?” Further subanalysis aimed to investigate the impact of the abutment material, macroscopic design, surface topography and surface manipulation. Randomised controlled trials (RCTs) with a follow‐up of at least 6 months after implant loading were considered as inclusion criteria. Meta‐analyses were performed whenever possible.

Results

Nineteen final publications from thirteen investigations were included. The results from the meta‐analysis indicated that zirconia abutments (Zi) experienced less increase in BOP values over time [n = 3; WMD = ?26.96; 95% CI (?45.00; ?8.92); p = .003] and less plaque accumulation [n = 1; MD = ?20.00; 95% CI (?41.47; 1.47); p = .068] when compared with titanium abutments (Ti). Bone loss was influenced by the method of abutment decontamination [n = 1; MD = ?0.44; 95% CI (?0.65; ?0.23); p < .001]. The rest of the studied outcomes did not show statistically significant differences.

Conclusions

The macroscopic design, the surface topography and the manipulation of the implant abutment did not have a significant influence on peri‐implant inflammation. In contrast, the abutment material demonstrated increased BOP values over time for Ti when compared to Zi abutments.

     

Optical phenomenon of peri-implant soft tissue. Part II. Preferred implant neck color to improve soft tissue esthetics

OBJECTIVES: The purpose of this study was to investigate an optical solution to eliminate the undesirable shine-through effect of implants on peri-implant mucosa by selecting an optimized implant neck color based on an objective and quantifiable method. MATERIAL AND METHODS: The optical effect of color strips on 15 peri-implant mucosal sites of 14 patients with Straumann single-tooth implant replacements in the maxillary anterior region was analyzed. The color differences between the peri-implant mucosa with insertion of each of eight different color strips (white, black, light pink, pink, light orange, orange, gold, violet) and the gingiva of an adjacent or contralateral tooth without any color strips were compared for the selection of optimal color of implant neck. Spectrophotometric color measurements were performed to compare the color difference index (DeltaE) and color coordinates (DeltaL*, Deltaa*, Deltab* and DeltaC*). RESULTS: The colors of the peri-implant mucosa with color strips and the gingiva of natural tooth demonstrated that the test site soft tissue with color strips of light pink, pink, light orange and orange showed a significantly smaller DeltaE value (P<0.05). Moreover, light pink exhibited the lowest mean DeltaE value of 2.6+/-0.6, indicating a clinically indistinguishable color difference. CONCLUSIONS: The results suggest that it is possible to improve gingival esthetics by coloring the implant neck, most effectively with light pink, to mask the impact of the underlying titanium implant. The use of implants with optimized neck colors to correct an esthetic deficiency may be a feasible approach to establish improved peri-implant soft tissue esthetics.