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This article defines immunophenotypes of stromal inflammatory and endothelial cells and fibroblasts 3 months after augmentation of the peri-implant soft tissue using a porcine cross-linked collagen matrix (VCMX). Peri-implant soft tissue samples were obtained from 12 patients at the lining mucosa (LM)-masticatory mucosa (MM) junction before (1) and 3 months after (2) augmentation. Immu-nohistochemical stains were performed to identify inflammatory cells (T [CD3] and B [CD20] lymphocytes, plasma cells [CD138]), macrophages (CD68-proinflammatory, CD163-anti-inflammatory/ reparative), endothelial cells (CD31, CD34), and fibroblasts (CD90, TE-7). Differences in the mean positively stained cells pre- and postaugmentation were analyzed by Wilcoxon signed-rank test. CD31+ endothelial cells showed increased mean numbers in MM2 compared to MM1 (P = .025) and in LM2 compared to LM1 (P = .047). CD163+ anti-inflammatory macrophages showed higher mean numbers in MM2 than in MM1 (P = .021) and in LM2 than in LM1 (P = .012). All other cell phenotypes showed nonsignificant changes between pre- and postaugmentation. This molecular study provides novel insight on the frequency of stromal cell phenotypes in the wound healing process at 3 months postaugmentation with VCMX, with anti-inflammatory CD163+ macrophages being predominant. This should be further investigated to help find novel therapeutic approaches to modulate and promote the VCMX-related healing process. [ABSTRACT FROM AUTHOR]

Purpose: To assess the clinical concept of patient treatment with fixed tooth- and implant-supported restorations in a university-based undergraduate program after 13 to 15 years. Materials and Methods: In total, 30 patients (mean age 56 years) who had received multiple tooth- and implant-supported restorations were recalled after 13 to 15 years. The clinical assessment comprised biologic and technical parameters as well as patient satisfaction. Data were analyzed descriptively, and the 13- to 15-year survival rates for tooth- and implant-supported single crowns and fixed dental prostheses (FDPs) were calculated. Results: The survival rate of tooth-supported restorations amounted to 88.3% (single crowns) and 69.6% (FDPs); in implants, it reached 100% for all types of restorations. Overall, 92.4% of all restorations were free of technical complications. The most common technical complication was chipping of the veneering ceramic (tooth-supported restorations: 5.5%; implant-supported restorations: 13% to 15.9%) regardless of the material used. For tooth-supported restorations, increased probing depth = 5 mm was the most frequent biologic complication (22.8%), followed by endodontic complications of root canal-treated teeth (14%) and loss of vitality at abutment teeth (8.2%). Peri-implantitis was diagnosed in 10.2% of implants. Conclusions: The results of this study indicate that the clinical concept implemented in the undergraduate program and performed by undergraduate students works well. The clinical outcomes are similar to those reported in the literature. In general, the majority of biologic complications occur in reconstructed teeth, whereas implant-supported restorations are more prone to technical complications. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess volumetric and linear changes of buccal mucosal thickness at implant sites following soft tissue augmentation with a volume-stable collagen matrix (VCMX). Soft tissue augmentation using a VCMX was performed in 12 patients at the time of implant placement. Hydrocolloid impressions were taken prior to surgery and at 1 and 6 months postsurgery. Stone cast models were scanned, and stereolithography (STL) files from the three time points were uploaded to an image-analysis software. At all time points, linear and volumetric measurements of the contour changes up to 3 mm apical to the mucosal margin were performed and were analyzed statistically. At 1 mm apical to the mucosal margin, the change in soft tissue thickness between presurgery (T1) and 1 month (T2) amounted to 0.21 ± 1.22 mm, and the change between T1 and 6 months (T3) was 0.08 ± 1.47 mm. At 3 mm apical to the mucosal margin, the change in soft tissue thickness was 1.92 ± 1.70 mm between T1 and T2 and 0.31 ± 1.26 mm between T1 and T3. Contour (volumetric) changes revealed an increase of 0.58 ± 0.73 mm between T1 and T2 and an overall gain of 0.55 ± 0.73 mm between T1 and T3. Soft tissue augmentation with VCMX increased the ridge profile. The increase in ridge width was greater at 3 mm below the ridge crest than at 1 mm below the ridge crest. Remodeling processes during healing showed a decrease in the ridge contour between 1 and 6 months. [ABSTRACT FROM AUTHOR]

Purpose: To assess the clinical, technical, and esthetic outcomes of directly veneered zirconia abutments cemented onto non-original titanium bases over 3 years.Materials and Methods: A total of 24 healthy patients with a single missing tooth in the maxilla or mandible (incisors, canines, or premolars) received a two-piece implant with a screw-retained veneered zirconia restoration extraorally cemented on a titanium base abutment. Baseline measurements and follow-up examinations were performed at 6 months, 1 year, and 3 years following loading. Radiographic, clinical, technical, and esthetic parameters were assessed. Wilcoxon signed rank test was used to analyze the data.Results: Mean marginal bone levels measured 0.54 ± 0.39 mm (median: 0.47 mm, range: 0.07 mm to 1.75 mm) at baseline and 0.52 ± 0.39 mm (median: 0.39 mm, range: 0.06 mm to 1.33 mm) at 3 years. Mean probing depth around the implants increased from 3.0 ± 0.6 mm at baseline to 3.8 ± 0.8 mm at 3 years (P = .001). Bleeding on probing changed from 27.1% ± 20.7% (baseline) to 51.5% ± 26.1% (3 years) (P = .001). The mean plaque control record amounted to 11.1% ± 21.2% (baseline) and 14.4% ± 13.89% (3 years) (P = .261). Two implants were lost at 3.5 and 30 months postloading due to peri-implantitis, resulting in a 91.7% implant survival rate. Patient satisfaction was high at 3 years.Conclusion: Zirconia restorations cemented onto the tested non-original titanium bases should not be recommended for daily clinical use, as they were associated with significant increases in BOP and PD values and varying marginal bone levels 3 years after placement. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to assess the perceptibility and acceptability threshold values for color differentiation at the restoration and mucosa levels.Materials and Methods: One restored single-tooth implant and the contralateral reference tooth were spectrophotometrically assessed in 20 patients. Perceptibility and acceptability were evaluated by dentists, dental technicians, and laypeople.Results: Dental technicians had the highest sensitivity in the perception of tooth color differences (ΔE = 2.7), followed by dentists (ΔE = 3.3) and laypeople (ΔE = 4.4). Acceptability threshold values were generally higher than perceptibility threshold in all groups. Dental technicians exhibited the highest sensitivity in the perception of mucosa color differences (50% perceptibility at ΔE = 2.65), followed by dentists (ΔE > 3.7) and laypeople (ΔE > 6).Conclusion: Color differences were tolerated with varying degrees among the three groups. Laypeople accepted higher color differences at the mucosa level. [ABSTRACT FROM AUTHOR]

Purpose: To assess the clinical outcomes of single-retainer resin-bonded fixed dental prostheses (RBFDPs) and the profilometric changes of pontic sites after a mean of 10 years in function.Materials and Methods: Ten patients (mean age 32.4 years) who had received an RBFDP replacing a single anterior tooth were recalled after 10 years. Five patients had received a subepithelial connective tissue graft (SCTG) at the pontic site. The clinical assessment comprised the following parameters: probing depth, bleeding on probing, modified plaque control record, gingival recession, measurement of the width of keratinized mucosa, and intraoral photographs and radiographs. The modified criteria of the United States Public Health Services evaluation system were applied. Additionally, patient satisfaction was recorded. Data were analyzed descriptively, and the 10-year RBFDP survival rates were calculated using Kaplan-Meier analysis.Results: The RBFDP survival rate after a mean follow-up of 10.0 years (range 7.4 to 13.3 years) was 100%. Neither technical failures nor biologic complications were observed. All abutment teeth remained vital, and no secondary caries were detected. Between baseline and follow-up examinations, the profilometric changes at the pontic sites were minimal, exhibiting a loss of -0.03 ± 0.10 mm (no SCTG) and 0.00 ± 0.37 mm (SCTG).Conclusion: The present study exhibited high survival rates and low complication rates of the restorations, as well as excellent profilometric stability of the pontic sites over 10 years. The use of an RBFDP is a viable long-term treatment option for replacing a single anterior tooth. [ABSTRACT FROM AUTHOR]

Purpose: To clinically and histomorphometrically compare a biphasic calcium phosphate (BCP) and deproteinized bovine bone mineral (DBBM) for sinus floor elevation. Materials and Methods: Sinus floor elevation procedures (lateral window) were performed randomly applying either BCP (test) or DBBM (control). At 6 months, bone biopsy specimens were harvested and dental implants were placed. The proportions of new bone, residual grafting material, and nonmineralized soft tissue were calculated. Four months after implant placement, the prosthetic reconstructions were inserted and the implant survival was assessed. Results: Fifty-one patients were treated; 25 were randomly allocated to the BCP group and 26 to the DBBM group. After 6 months in 50 patients, bone biopsy specimens could be harvested, and a total of 121 implants could be placed subsequently. The histomorphometric analysis revealed a comparable percentage of new bone in both groups (BCP 35.9%, DBBM 35.4%; P > .05). The remaining grafting material was significantly lower with BCP (25.3%) compared with DBBM (45.9%; P < .001). Nonmineralized tissue was significantly higher for the BCP group (38.1%) compared with the DBBM group (18.2%; P < .001). The implant survival rate at loading was assessed at the level of the patients (96.0% for BCP and 88.8% for DBBM; P > .05) and at the level of the implants (96.9% for BCP and 94.7% for DBBM; P > .05). Conclusion: Grafting with DBBM or BCP showed similar percentages of new bone 6 months after sinus floor elevation. Implant survival presented no significant difference until loading. [ABSTRACT FROM AUTHOR]

Peri-implant bone dehiscences were grafted either with deproteinized bovine bone mineral (DBBM) block or with particulate DBBM, both covered with a collagen membrane and stabilized with resorbable pins. After 6 months, 17 biopsy samples were included for histologic assessment. Block and particulate DBBM rendered successful tissue integration. Particulate DBBM showed a median of 25.2% of new bone and 31.3% of bone substitute. In the block group, there was a median of 11.5% of new bone and 36.0% of bone substitute. When interpreting the discrepancy in new bone between the groups, the difference in the size of the augmented hard tissue needs to be taken into account. [ABSTRACT FROM AUTHOR]

The objective of this trial study was to assess whether submucosal veneering of internally connected zirconia abutments influences clinical, radiographic, and technical outcomes of single-tooth implant-borne reconstructions at 5 years after loading. A total of 20 patients with 20 single-tooth implants in the anterior or premolar area of the maxilla or mandible were included. The implants were randomly restored with fixed single-tooth reconstructions using either pinkveneered customized zirconia abutments (test group = 10) or nonveneered customized zirconia abutments (control group = 10). All reconstructions were adhesively cemented with all-ceramic crowns. Follow-up examinations were performed at baseline (7 to 10 days after crown insertion) and at 1, 3, and 5 years after loading, at which points the following were assessed: periodontal parameters such as probing depth (PD), bleeding on probing (BOP), and marginal bone levels, as well as technical outcomes using the modified United States Public Health Service (USPHS) criteria. Statistical comparisons were based on the Wilcoxon- Mann-Whitney test. Sixteen patients attended the 5-year follow-up. At 5 years, the implant survival rate was 100% and the prosthetic survival rate was 94.1% (one abutment fracture in the test group). Veneering of the submucosal part of zirconia abutments resulted in significantly higher mean PD values: 3.6 ± 0.4 mm (test group) and 3.0 ± 0.5 mm (control group), P = .042. Marginal bone levels at 5 years and changes up to 5 years were not significantly different between groups (P > .05). One crown exhibited an abutment fracture and two crowns a minor chipping (17.6% overall technical complication rate). Limited by a small sample size, veneering of the submucosal part of internally connected zirconia abutments led to outcomes that were less favorable biologically (PD, BOP, and KM), but similar to nonveneered abutments radiographically and technically. [ABSTRACT FROM AUTHOR]

Purpose: To assess the biologic and technical responses to cemented and screw-retained all-ceramic single-tooth implant-supported reconstructions at 3 years postinsertion.Materials and Methods: Thirty-four patients with single-tooth implants were randomly restored with either a cemented lithium disilicate crown on a customized zirconia abutment (CEM) or a screw-retained crown with a directly veneered zirconia abutment (SCREW). At baseline examination and after 3 years of loading, marginal bone level and technical parameters were assessed. Differences in marginal bone loss were tested using Mann-Whitney U test at baseline and at 3 years, and changes within each group between baseline and 3 years were tested using Wilcoxon signed rank test.Results: The median changes between baseline and the 3-year follow-up amounted to -0.1 mm (CEM; intragroup P = .36) and -0.0 mm (SCREW; intragroup P = .58). Intergroup comparisons did not reveal statistically significant differences at 3 years (P = .20) or over time (P = .70).Conclusion: At 3 years, screw-retained and cemented reconstructions rendered largely the same radiographic and technical outcomes. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the discoloration of the peri-implant mucosa caused by zirconia (Zr) and titanium (Ti) dental implants with and without soft tissue grafting (STG). Zr and Ti implants were inserted in edentulous areas in pig maxillae. Spectrophotometric measurements were performed prior to and after the insertion of the implants, and following the placement of a STG on the buccal side. A significant discoloration of the mucosa was observed with a mean ΔE of 8.05 (± 2.51) (Ti) and 4.93 (± 3.18) (Zr). In conjunction with a STG, ΔE values amounted to 5.31 ± 3.50 (Ti) and 5.95 (± 3.68) (Zr). The placement of Zr implants led to less discoloration of the mucosa than Ti implants without STG. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the threshold value for the perception of color changes of human gingiva. Standardized presentations of five cases in the esthetic zone were made with the gingiva and teeth separated. The color parameters L, a, and b (CIELab) of the gingival layers were adjusted to induce darker and lighter colors. In the presentations, the right side (maxillary right anterior) was unchanged, while the left side (maxillary left anterior) of the pictures was modified. Ten dentists, 10 dental technicians, and 10 lay people evaluated the color difference of the pictures. The mean ΔE threshold values ranged between 1.6 ± 1.1 (dental technicians) and 3.4 ± 1.9 (lay people). The overall ΔE amounted to 3.1 ± 1.5. [ABSTRACT FROM AUTHOR]

No human studies exist on the use of recombinant human bone morphogenetic protein 2 (rhBMP-2) on an absorbable collagen sponge (ACS) as a sole graft material for lateral ridge augmentation in large ridge defect sites. This series evaluates the treatment outcome of maxillary anterior lateral ridge augmentation with rhBMP-2/ACS. Twenty patients were treated with rhBMP-2/ACS and fixation screws for space maintenance. Cone beam volumetric tomography measurements were used to determine gain in ridge width, and a bone core biopsy was obtained. The mean horizontal ridge gain was 1.2 mm across sites, and every site gained width. [ABSTRACT FROM AUTHOR]

The aim of this study was to test whether veneering of the submucosal part of zirconia abutments using pink veneering ceramic positively influences the color of the peri-implant mucosa. Single-tooth implants were restored with either white zirconia abutments (control group) or pink-veneered zirconia abutments and allceramic crowns. Esthetic outcome measurements included a spectrophotometric evaluation of the peri-implant mucosal color. Test and control groups induced a visible discoloration of the peri-implant mucosa after the insertion of the abutments and following cementation of the crowns compared to natural teeth. The calculated color differences were above the clinically visible threshold value and were more favorable for the control group, although not statistically significant. It is concluded that veneering of zirconia abutments with pink veneering ceramic failed to positively influence the esthetic outcome, mostly due to a decrease of the brightness compared with the control group. [ABSTRACT FROM AUTHOR]

The aim of this study was to test whether recombinant human platelet-derived growth factor BB (rhPDGF-BB) enhances bone regeneration in combination with β-tricalcium phosphate (β-TCP) granules or deproteinized bovine bone mineral (DBBM) compared to empty defects and β-TCP granules alone. Four titanium cylinders were placed on the external cortical plates of seven rabbits' calvaria and randomly allocated to one of four groups: (1) empty, (2) β-TCP, (3) β-TCP + rhPDGF-BB, and (4) DBBM + rhPDGF-BB. The mean area of bone regeneration was 13.9% ± 8.4% (empty), 24.0% ± 14.8% (β-TCP), 37.1% ± 8.9% (β-TCP + rhPDGF-BB), and 64.4% ± 5.4% (DBBM + rhPDGF-BB), with the greatest bone regeneration noted for DBBM + rhPDGF-BB (P < .01). The fraction of bone substitute material varied between 48.3% ± 9.3% (DBBM + rhPDGF-BB), 53.1% ± 10.6% (β-TCP + rhPDGF-BB), and 58.0% ± 14.8% (β-TCP). rhPDGF-BB combined with DBBM showed the greatest potential to enhance bone regeneration. [ABSTRACT FROM AUTHOR]