Effectiveness of soft tissue augmentation procedures for coverage of buccal soft tissue dehiscence around dental implants: A systematic review.

OBJECTIVE: This systematic review evaluated the effectiveness of soft tissue augmentation procedures for complete coverage and mean coverage of buccal soft tissue dehiscence (BSTD) in patients with implant-supported restorations. METHODS: Three databases were surveyed for randomized (RCTs), non-randomized controlled clinical trials (CCTs), cohort studies, case-control studies, and case series with a minimum of five patients per control or test group. Studies dealing with soft tissue augmentation procedures to cover BSTD-occurring during implant function and not due to the result of peri-implantitis-were included. Risk of bias was evaluated with RoB 2 or the National Institutes of Health's Quality Assessment. Whenever possible, exploratory meta-analyses were performed to evaluate weighted mean effects (WME) for the different outcomes. The primary outcomes were the percentage of complete coverage and mean coverage of BSTD. RESULTS: Seven articles were included. Only one study was a RCT, with a high risk of bias. Meta-analyses showed that after 1 year (2 studies, n = 36 patients; WME = 70; 95% confidence interval [CI] = 50; 90; p = .23) as well as after 5 years (3 studies, n = 54 patients; WME = 70; 95%; CI = 60; 80; p = .44), complete coverage of BSTD could be achieved in 70% of the cases. CONCLUSION: Based on limited evidence, it can be concluded that BSTD can be substantially reduced with the use of soft tissue augmentation procedures. Further research with comparative trials using larger samples and longer follow-up periods is needed to study the stability of soft tissues in the long term.

In vivo full-arch accuracy of intraoral scanners: a narrative review.

AIM: The present narrative review aims to provide an overview of the in vivo accuracy of full-arch scans performed with currently used intraoral devices and to compare different methods for the determination of in vivo accuracy. Materials and methods: An electronic search was performed with the PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases, including articles from 2015 to 2020. Specific search strategies were developed for each platform. RESULTS: The final search resulted in five published articles. The mean values of trueness and precision of the examined scanners ranged from 12.9 to 80.01 µm for trueness and from 42.9 to 86.0 µm for precision in full-arch dentition. Not all studies evaluated both trueness and precision. Furthermore, the methods and references for determining the in vivo accuracy proved to be very different. CONCLUSION: To date, no scientific consensus on the required accuracy of in vivo full-arch scans has been reached and published. Due to the small number of studies on the in vivo accuracy of full-arch scans, further studies should be conducted in this area. In addition, a concept for a valid reference that can be scanned both extraorally and intraorally should be developed.

Gender- and age-related differences in the width of attached gingiva and clinical crown length in anterior teeth.

BACKGROUND: The anatomical features of the gingiva and the clinical crowns and their interrelation, especially in aesthetically and functionally demanding areas, are important in complex dental or implant-retained prosthetic rehabilitations. This observational cross-sectional study was designed to evaluate gender- and age-related differences in the width of attached gingiva (WAG), the clinical crown length (CCL), and their interrelation in the anterior teeth to determine the relationship between the pink and white aesthetics. METHODS: Eighty (54 females, 26 males) fully dentate Caucasian participants between the ages of 20 and 25 years and 36 probands (23 females, 13 males) between the ages of 45 and 55 years were included in the present study. The CCL of the maxillary and mandibular canines, as well as the central incisors of the maxilla and mandible, were determined with a dental sliding caliper measuring from the middle margin of the gingiva at its deepest point to the incisal edge. The clinical investigation of the WAG was performed by inserting a periodontal probe into the gingival sulcus in the middle of the buccal surface to firstly measure the probing pocket depth. The distance between the gingival margin and mucogingival junction (MGJ) was then measured with a Beerendonk sliding caliper in the middle of the labial curvature, and the clinical WAG was determined by subtraction of the measured probing depth. For the statistical analysis, the Mann-Whitney U test, the Wilcoxon-Test, the Spearman's rank correlation, and a two-factorial non-parametric analysis were used. RESULTS: There was no correlation between the CCL and the WAG in a healthy periodontium. Gender influenced the CCL, with men having significantly longer teeth than women in both maxilla (P ≤ 0.01) and mandible (P ≤ 0.05). Age did not influence the CCL significantly neither in the upper (P = 0.06) nor in the lower jaw (P = 0.33). Gender did not show to have a significant influence on the WAG of maxilla (P = 0.69) and mandible (P = 0.26). But differences in the WAG between young and old participants were observed in both upper (P ≤ 0.01) and lower jaw (P ≤ 0.05). CONCLUSION: The present observational study demonstrated that the mean values of cohorts with mixed age groups and genders should not be considered when attempting to determine the ideal relationships between the pink and white aesthetics since the statistical analyses showed significant differences between different age groups and genders.

Response of human gingival keratinocytes to hybrid CAD/CAM material eluates.

OBJECTIVES: The aim of this study was to investigate the influence of hybrid CAD/CAM-blocks on immortalized human gingival keratinocytes (HGK). METHODS: Samples of two different hybrid CAD/CAM materials [Lava™ Ultimate (3 M); VITA Enamic® (VITA Zahnfabrik)], a composite material [ceram.x® universal (Dentsply Sirona)] and a CAD/CAM ceramic [VITABLOCS® (VITA Zahnfabrik)] were stored in cell culture medium for 72 h to prepare eluates according to ISO-10993-12:2012. HGK were exposed to eluates for 6, 24 and 48 h. Cell monitoring was performed by RTCA iCELLigence™ system. The morphological changes were evaluated using phase contrast imaging. Specific biomarkers of apoptosis and terminal differentiation (Caspase-3, Involucrin) were analyzed semi quantitatively by indirect immunofluorescence (IIF). Protein levels and activation of MAP kinases ERK1/2 (p44/42) were quantified by Western blot. Data were statistically analyzed by unpaired t-test (p < 0.05). RESULTS: Regarding Vita Enamic® and Lava™ Ultimate, results of RTCA iCELLigence™ and Western blots showed no statistically significant differences (p > 0.05) compared to the negative control (HGK in native keratinocyte growth medium). No aberrant expression of Caspase-3 and Involucrin was detected in cells incubated with Vita® Enamic eluates Cells incubated with Lava™ Ultimate showed a higher expression of Involucrin after 24 h of incubation compared to the negative control. Statistically significant differences (p < 0.01) were found between cells incubated with ceram.x® universal and the negative control in RTCA iCELLigence™ assay and in quantitative measurements of Western blots after 6 h against phospho-p44/42 (p = 0.044). Increased expression of Caspase-3 and Involucrin were detected by IIF in cells after incubation with eluates of ceram.x® universal. SIGNIFICANCE: The present data show no significant effect of hybrid materials on analyzed functions of cell behavior. A cytotoxic influence of ceram.x® universal eluates was observed in HGK in terms of a strong modulation of proliferation, morphology and protein expression.

Esthetic and functional rehabilitation of severe facial asymmetry and dental attrition in a patient with hemifacial microsomia: an interdisciplinary treatment outcome.

The treatment management of patients with hemifacial microsomia (HM) includes both surgical and nonsurgical approaches and depends primarily on the degree of deformity of the facial and skeletal structures. In this context, the combined efforts of the maxillofacial surgeon, the orthodontist, and the prosthodontist are essential for a satisfactory functional and esthetic outcome. Case presentation: A 31-year-old man presented with a chief complaint of facial asymmetry. The patient had been diagnosed with HM on the right side, with severe external ear deformity, and hypoplasia of the facial muscles and the zygomatic bone. The intraoral examination showed a Class I molar and canine relationship with a reduced horizontal overlap and an occlusal plane canting. The maxillary anterior teeth were severely worn due to traumatic occlusion. Orthodontic treatment in conjunction with combined orthognathic surgery was planned to address the facial asymmetry. Ramus distraction osteogenesis was carried out, followed by conventional presurgical orthodontic treatment. The treatment was completed by prosthetic rehabilitation for the reconstruction of the maxillary teeth and fine occlusal adjustment. Conclusion: The cooperation between the orthodontist, surgeon, and prosthodontist becomes indispensable when treating complex cases of HM. An interdisciplinary approach should be adopted from the start of treatment, promoting integrated customized care.

Antibacterial Effects of Modified Implant Abutment Surfaces for the Prevention of Peri-Implantitis-A Systematic Review.

The aim of the present study was to systematically review studies investigating antibacterial implant abutment surfaces or coatings, which may suppress bacterial growth to prevent plaque-induced peri-implant inflammatory disease. Data were collected after identification of case, assay/laboratory procedure, predicate/reference standard and outcome (CAPO). Seven hundred and twenty (720) records were identified through data base searching. After screening nine publications fulfilled inclusion criteria and were included. The following surfaces/coatings showed antibacterial properties: Electrochemical surface modification of titanium by the anodic spark deposition technique; doxycycline coating by cathodic polarization; silver coating by DC plasma sputter; titanium nitride; zirconium nitride and microwave assistant nano silver coating. Since the current state of the literature is rather descriptive, a meta-analysis was not performed. While several abutment coatings showed to have antibacterial capacity, some of them also influenced the behavior of investigated human cells. None of the studies investigated the long-term effect of surface modifications. Since surface changes are the main contributing factor in the development of antibacterial effects, the biodegradation behavior must be characterized to understand its durability. To date there is no effective structure, material or strategy to avoid peri-implant inflammation used as clinical routine. Furthermore, clinical studies are scarce.