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Collagen and multifunctional epoxides, which are respectively the common constituents of natural and polymer interfaces, were combined to fabricate integrative biointerfaces with device/tissue heterogeneous affinity. Further, the traditional 2D and advanced 2.5D conformational designs were achieved on collagen-based biointerfaces. The 2D conformational biointerfaces were formed by the self-entanglement of collagen molecules based on extensive hydrogen bonds among molecules, and the lamellar structures of 2D conformational biointerfaces could act as barriers to protect both biointerfaces and substrates from enzymes and corrosion. The unique stacking structures of 2.5D conformational biointerfaces were formed by cross-linking microaggregates that were established and connected by epoxy cross-linking bonds and provided the extra 0.5D degree of freedom on structure design and functional specialization through artificially manipulating the constituents and density of microaggregates. Besides, the intersecting channels among microaggregates gave 2.5D biointerfaces diffusion behaviors, which further brought good wettability and biodegradability. The integrative biointerfaces behaved well on cell viability and enhanced the cell adhesion strength in vitro, which could be attributed to the collaborations of collagen and epoxy groups. The subcutaneous implant model in rats was utilized to investigate soft tissue response, and the results demonstrated that the tissues around implantation areas healed well and without calcification or infection. The coating of integrative biointerfaces alleviated the fibrosis around implantation areas, and the inflammatory responses and foreign body reactions were improved.

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Objective: To define the dental and skeletal characteristics of Class III surgery patients with ideal final soft-tissue profiles, and to compare them with those of Class I subjects. Also, to show how soft-tissues respond to surgical jaw movements and contribute to the outcome. Methods: This short-term, retrospective study was conducted using pre-treatment (T0), pre-surgery (T1), and post-treatment (T2) records of 50 double-jaw Class III surgery patients who presented with ideal cephalometric characteristics in sagittal (Holdaway and soft-tissue convexity angles) and vertical dimensions (GoGn. SN angle and upper-to-lower face harmony) at the end of treatment, and 50 control subjects. Results: At T2, the horizontal distance between the vertical reference plane (a perpendicular plane to the horizontal reference plane that is angulated 7° clockwise to the SN plane) and hard-tissue A, B and Pog points, lower lip, soft-tissue B, and pogonion points were greater, Wits appraisal was more negative, U1.PP was higher, IMPA was lower, and soft-tissue chin (Pog-Pog') was thicker in Group 1 when compared to Group 2 (p<0.05). Moreover, upper lip and subnasal (A-A') thicknesses were decreased, and chin thickness (Pog-Pog') was increased significantly (p<0.05). Conclusion: Dentoskeletal characteristics of an ideally-treated Class III surgery patient differed from a Class I subject concerning a protrusive maxilla and soft-tissue pogonion, and incisors that were not fully-decompensated. Soft-tissues hindered the actual surgical correction to 66% and 73% in the mid- and lower-faces, respectively.

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OBJECTIVES: Aim of this study was to compare the soft tissue response to implant abutments made of titanium, zirconia, zirconia veneered with feldspar ceramics and PEEK by various clinical, histological, microbiological, and molecular biological markers in an experimental model. MATERIALS AND METHODS: A total of 40 experimental one-piece healing abutments of four different materials were mounted on bone level implants in 20 volunteering patients (split-mouth design). After a three-month period of open healing, clinical parameters at the abutments were assessed and adjacent mucosa was sampled for inflammatory cytokine mRNA concentrations and histological analysis by a novel method. In addition, PISF samples were obtained for the analysis of periodonto-pathogenic bacteria counts and active MMP-8 levels. Marginal bone level change was measured by intra oral radiographs. RESULTS: Abutments of the different materials did not exhibit significant differences regarding clinical parameters, pathogenic bacteria counts or pro-inflammatory cytokine concentrations. Likewise, no significant differences were detected regarding soft tissue morphology or bone level change. Compared to titanium abutments, significantly less mononuclear inflammatory cells were detected in the mucosa at abutments made of zirconia veneered with feldspar ceramics. CONCLUSIONS: All examined abutment materials exhibited a similar soft tissue response compared to titanium and histological data did not reveal early signs of elevated inflammation caused by PEEK- and feldspar-veneered zirconia abutments. Due to the short observation period and the small sample size, a final conclusion on the long-term suitability of those abutment materials cannot be drawn. However, based on the presented data, we consider further studies on that subject as appropriate.

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OBJECTIVES: This open, single-cohort, multicenter, prospective study investigated the efficacy of immediately provisionalized tapered conical connection implant for single-tooth restorations in the anterior and premolar regions of the maxilla after 5 years of function. MATERIALS AND METHODS: All implants were placed in healed sites and immediately provisionalized. MBLs, soft-tissue parameters, and oral-health impact profile (OHIP) were evaluated at implant insertion, 6, 12, 24, 36, and 60 months. Paired Wilcoxon signed-rank tests and Kaplan-Meier survival analysis was used for statistical and implant survival/success analyses, respectively. RESULTS: Seventy-seven patients (81 implants) completed the 5-year follow-up. The 5-year cumulative survival and success rates were 97.8%, and the mean MBL change from implant insertion to 5 years was - 0.80 ± 1.13 mm. Optimal papilla index scores were observed at 90.1% of sites at 5 years compared with 32.8% of sites at insertion. Pink esthetic score, modified bleeding and plaque indices, and OHIP showed statistically significant improvement at the 5-year follow-up. CONCLUSIONS: Immediately provisionalized tapered conical connection implants promote marginal bone stability and excellent esthetic outcomes after 5 years of function. CLINICAL RELEVANCE: This treatment is a viable option for patients requiring immediately provisionalized single-tooth restorations in the esthetic zone and shows favorable long-term clinical outcomes, including marginal bone stability and excellent esthetics.

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AIMS & OBJECTIVES: To analyze the soft tissue response in patients treated by combined anterior segmental bimaxillary procedures. METHODS: A  Prospective, observational and analytical study was carried out for a period of 2 years involving 37 patients with predefined inclusion and exclusion criteria; lateral cephalograms were taken by the same operator on the standardized unit immediately before and 6 months after surgery; hard and soft tissue landmarks were measured in millimeters to both horizontal and vertical reference lines; any differences in distances were recorded as a surgical change; appropriate statistical test was carried; level of significance was p < 0.05. RESULTS: All patients underwent anterior maxillary osteotomy with 34 anterior mandibular osteotomies, 2 advancement genioplasties and 1 reduction genioplasty. Analysis showed significant angular, horizontal and vertical change. The significant differences in skeletal variables were observed in N-Pg distance, overjet, overbite, U1-NF angle, L1-Mp angle and soft tissue variables like labiomental angle, upper-lower lip protrusion, upper-lower lip length and lower incisor to labrale inferius distance. Nasolabial angle, interlabial gap and upper incisor exposure were extremely significant. CONCLUSION: Soft tissue response to surgery is perhaps more predictable after 6 months, so this may be a treatment modality of choice in adult bimaxillary/dentoalveolar protrusion patients who need instant esthetic facial results.

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According to the study, there were unexpected tiny bone spicules being inspected in peri-implant soft tissue. These displaced autogenous bone chips were probably presented when preparing implant sites. The displaced bone spicules seemed not induced significant inflammatory reactions; on contrary, defects of specimens and dissolving bone spicules pictures were demonstrated.

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INTRODUCTION: Plasma application can lead to an improved adhesion between soft tissue and abutments and promotes cell spreading. OBJECTIVE: A triple-blinded randomized controlled clinical trial was performed to in vivo test the effect of cleaning abutment titanium surfaces with plasma of argon on cell adhesion and collagen fiber orientation at an early healing time. MATERIAL AND METHODS: Thirty healthy patients with 30 submerged implants, at the second surgery, randomly received either a specially designed abutment with no additional treatment (as they come from industry; control group, G1) or cleaned by plasma of argon (test group, G2). Two weeks thereafter, a small biopsy including abutment and soft tissues around the abutment was performed. Abutments were analyzed using scanning electron microscopy to assess cell adhesion to the abutment surface. Outcome measures were the following: percentage of area occupied by cells, the presence or absence of cells, aspect of adhered cells, and the presence of contaminants. At the same time, the soft tissue histological analysis evaluated density and orientation of collagen fibers. Statistical analysis was performed using the Kolmogorov-Smirnov normality test and Levene variance homogeneity test. Data were analyzed using a nonparametric ranking test. The associations between the different qualitative variables were studied using Pearson's chi-squared test. The Mann-Whitney U-test (for two independent samples) was applied for quantitative variables. RESULTS: Mean percentages of area occupied by cells were 15.14% (range 2.91-44.27) and 33.75% (range 2.37-68.4) for G1 and G2, respectively. Differences were close to significance (P = 0.089). The proportion of samples presenting adhered cells was homogeneous between the two groups (P = 0.142). In all cases, cells presented a flattened aspect, but not in three cases in the G2; in 17 cases, cells were efficiently adhered, and in 11 cases, cells presented filopodia with no statistical differences between groups (P > 0.05). No case from G2 showed contamination with cocobacteria with statistical differences between groups (P = 0.006). Collagen fiber density was higher in the basal, medial, and coronal area of G2 compared to G1 with a statistical difference in the internal area (P < 0.05). The orientation of the fibers varied according to the coordinate area with oblique fibers predominant in G2 than in G1. CONCLUSION: Plasma of argon may promote cell adhesion and positively influence collagen fiber orientation. A greater sample is necessary to confirm these preliminary results.

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PURPOSE: To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS: A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively. RESULTS: All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION: The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.

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PURPOSE: To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS: A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively. RESULTS: All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION: The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.

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PURPOSE: To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS: A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non-quantitatively. RESULTS: All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION: The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.

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AIM: To assess and characterize pollution micro-particles and bacterial growth on customized titanium abutments after steaming, ultrasonic and plasma cleaning treatments. MATERIALS AND METHODS: Thirty commercially available implant abutments, after customization, were randomly divided into 3 groups of 10 and cleansed by steam (considered as control group), ultrasonic cleaning (test group 1) and plasma of Argon (test group 2). For all specimens, SEM analysis and EDAX microanalysis were performed to count and characterize pollution micro-particles, both on the abutment surface and implant-abutment connection. For the control and test groups, mean values and standard deviations were calculated for number and density of micro-particles. Statistical differences were determined by one-way ANOVA with Scheffe multiple comparison test. The level of statistical significance was set at P ≤ 0.05. Additional microbiologic analysis was performed to detect bacterial contamination on the abutment surface. RESULTS: In the control group, the number of micro-particles on average was 117.5, and 14.1, respectively, on the abutment surface and connection. In the test groups, no pollution was revealed on the abutment (average of 1.09 and 1.13 spots, respectively, in test group 1 and test group 2) and connection (1.28 and 1.41, respectively, in test group 1 and test group 2). The analysis of variance (ANOVA) showed a statistically significant difference for all the variables examined. For each variable, at least one of the groups differs from the others. Scheffe multiple comparison test showed that all comparisons for every variables between the control group and both groups are significant, while there were some comparisons between test group 1 and test group 2 that were not significant. EDAX microanalysis identified micro-particles as residual of lubricant mixed with traces of Titanium and other metals. Microbiologic analysis demonstrated the presence of bacterial growth on the abutment surface only in the control group (111.5 ± 11.43 CFU/ml/implant-abutment as mean value). In the test groups, absence of growing microorganisms was found. CONCLUSIONS: This study confirmed that both plasma and ultrasonic treatments can be beneficially adopted for abutment cleaning process after laboratory technical stages, to supposedly favor soft tissue healing and implant-prosthetic connection stability.

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The issue of metal release from stainless steel bone plates has gained considerable momentum advocating the removal of stainless steel miniplates after healing of fracture. So far no study has been published in the literature regarding metal release with the indigenously manufactured stainless steel miniplates.Objective Aim of the study was to find any pathological changes at cellular and ultracellular levels and metal particles in the soft tissue surrounding the stainless steel miniplates.Method Retrieval of indigenous stainless steel implants, used in treatment of jaw fractures, samples of surrounding soft tissue were histopathologically assessed for tissue response as well as metal release, using light microscope and Transmitted Electron Microscope (TEM).Result Light microscopic examination revealed chronic inflammation in symptomatic cases, but TEM did not show any significant pathological alteration and metal deposits even in cases with clinically observed pigmentation. Short-term (upto 1 year) retention of stainless steel mini plates will not cause any significant local complications.

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BACKGROUND: Little information exists concerning the periimplant soft tissue response to plaque compared to the gingiva of the dentition. The purpose of this study was to compare this relative tissue response to plaque in humans over time. METHODS: Two hundred seventy-five (275) hydroxyapatitecoated implants were placed in the maxillae of 50 subjects followed by prosthetic rehabilitation. Baseline gingival (GI) and plaque (PI) index scores were obtained for all implants. Two to 4 teeth per subject were similarly measured, serving as controls. Measurements were repeated at 6-month intervals over 30-months. GI scores were evaluated relative to PI scores at 4 separate sites for each implant, to implant location within the oral cavity, and to length of time that each implant was in function. RESULTS: The peri-implant mucosa demonstrated a significantly greater likelihood of having elevated GI scores relative to PI scores when compared to the gingiva (chi-square for combined PI scores of 0 and 1 = 85.0, df = 1, P <0.001; for combined PI scores of 2 and 3 = 114.6, df = 1, P <0.001). A logistic generalized linear model confirmed the significance of these results (Student t for implant effect = 21.602). It further demonstrated significantly elevated GI scores for implant sites over time and for implants located in the posterior oral cavity. CONCLUSIONS: The results indicate that maxillary peri-implant soft tissues are at increased risk for plaque-induced inflammation relative to the gingiva of the dentition. Hygiene recall standards and treatment regimens may require revisions to minimize peri-implantitis and prevent bone loss. J Periodontol 2001;72:1139-1145.

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