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Objectives: This clinical trial aimed to assess the effects of anodized prosthetic abutments versus machined abutments on peri-implant connective tissue. Materials and Methods: Following dental implant placement and osseointegration, custom healing abutments with machined surfaces (G1) and anodized surface treatment (G2) were attached to 28 dental implants. After a soft tissue healing period of approximately 30 days (±7 days), 5 mm circular biopsies were taken from the peri-implant tissue and the area adjacent to the prosthetic abutment. Histological analysis was conducted on the stained specimens using hematoxylin- eosin, focusing on parameters such as vascular proliferation, the presence of polymorphonuclear and mononuclear cells, collagen fibrils, and re-epithelialization. A grading scale from 0 to 3 evaluated the extent of the inflammatory response. Masson’s trichrome staining was used to analyze collagen fiber presence and organization, while immunohistochemical staining assessed the expression of beta-catenin and CD34. The prosthetic abutments were evaluated through electron microscopy and three-dimensional roughness analysis. Results: Histological findings revealed that peri-implant tissue adjacent to anodized surfaces exhibited epithelial stratification and a parakeratin layer in the lamina propria. Both groups displayed a typical mononuclear lymphocytic inflammatory infiltrate, but the intensity was significantly higher adjacent to the machined abutment (p<0.05). Quantification of blood vessels indicated increased immunopositivity for CD34 in G2 compared to G1 (p<0.05). Immunolabeling of beta-catenin was detected in the epithelial tissue, showing weak intensity in G1 and strong intensity in G2. The average surface roughness (Ra) measurements were determined to be 0.097 (0.006) µm for G1 and 0.182 (0.008) µm for G2. Conclusion: Anodized surfaces are promising and exhibit beneficial effects on peri-implant tissue healing. They play an important role in preserving the epithelial mucosal integrity and functionality near the prosthetic abutment, thereby potentially minimizing the risks of mucositis, peri-implantitis, and implant failure. Keywords: implant abutment surface; mucointegration; peri-implant soft tissues; anodized prosthetic abutments

Purpose: To evaluate the occurrence, incidence rate, and esthetic impact of facial growth in adult patients who need a single implant rehabilitation in the central incisor area to assess the influence of time on changes in the incisal level. Materials and Methods: Patients were included if they received a single implant in the maxillary central incisor site, were at least 19 years old at the time of placement, and had natural adjacent teeth. Standardized images were obtained to evaluate the presence and incidence of incisal linear changes. All rehabilitations followed the same standard of reconstruction, while always keeping the mimetics of the homologous and adjacent tooth the same to provide the same incisal level and achieve the best esthetics for all patients. Thus, at implant placement (T0), the incisal-level difference between the crown and the adjacent tooth was zero. Any modifications in the incisal levels from 1.0 mm of difference were registered. This measurement of 1.0 mm was the cutoff mark because it permits easy observation of a difference, either by the dental professional or the patient. The data obtained were analyzed and correlated statistically. Results: A total of 56 patients and 56 implants were included (age range: 23–63 years; average age: 40.79 ± 12.25 years) in this study. Incisal-level alterations between the tooth and implant were found and had an incidence rate of 19.6%. The study had an average follow-up of 10.7 ± 3.37 years. All implants evaluated had stability and healthy peri-implant tissue conditions throughout the followup period, with a 100% survival rate. There was no statistically significant prevalence of incisal-level changes between males (19%) and females (20%) (P = .238); the incidence rate was 41.7% for patients between 20 and 30 years old, 13.3% for patients between 31 and 40 years old, 23.7% for patients between 41 and 50 years old, and 6.3% in the group over 50 years old; note that there were no statistically significant differences (P = .118) among different age groups. Similarly, no statistically significant difference was observed (P = .262) comparing the number of clinical cases in each subgroup with and without change in the incisal level. Conclusions: Changes in the incisal level of maxillary anterior crowns retained by single implants in adult patients were present in 19.6% of the cases evaluated. This prevalence was not influenced by sex or age group; however, it was observed more often in dental implant cases with longer follow-ups. Keywords: anterior single implant, esthetics, facial growth, incisal level

Objectives: This systematic review aimed to search the literature for the answer to the following questions. In human studies: Does the osseodensification technique increase the resonance frequency analysis given in implant stability quotient value and the insertion torque value compared to the conventional technique? In animal studies: Does the osseodensification technique increase implant stability quotient, bone-to-implant contact, and bone area fraction occupancy values over the conventional technique? Data sources: A search for studies was carried out in eight databases until August 2021. Out of the 447 publications found, 11 were included. Results: In human studies, osseodensification technique showed better results for implant stability quotient values with a summarized median difference of 8.57. As for secondary stability, there was no significant difference, with summarized median difference of 4.49 in favor of the osseodensification technique. In animal studies, all results were favorable to the osseodensification technique. Regarding insertion torque, bone-to-implant contact, and bone area fraction occupancy between counterclockwise osseodensification technique vs conventional, the mean difference was 46.79 for insertion torque, 2.17 for bone-to-implant contact, and 2.11 for bone area fraction occupancy. High heterogeneity was observed between the studies. The risk of bias in humans was moderate in three studies and low in one; and in animal studies, four presented moderate risk, two low risk, and one high risk. The certainty of evidence ranged from low to moderate. Conclusion: The osseodensification technique showed improvement concerning the resonance frequency and the insertion torque value of implants in human studies. In addition, it increased the values of bone-to-implant contact, bone area fraction occupancy, and implant stability quotient in animal studies, when compared to the conventional technique. Keywords: conventional technique, dental implants, osseodensification

Ziel: Ziel dieser Untersuchung waren der Vergleich eines freien Gingivatransplantats (FGT) mit einer porkinen Kollagenmatrix (Mucograft Seal, MS) zum Weichgewebeverschluss im Bereich der Extraktionsalveole (Socket-Seal-Technik) sowie eine qualitative Bestimmung der Patientenwahrnehmung mithilfe visueller Analogskalen (VAS). Methode und Material: Insgesamt 18 Patienten mit Indikation für eine Einzelzahnextraktion in der ästhetischen Zone wurden per Randomisierung der Kontrollgruppe (FGT) oder der Testgruppe (MS) zugeordnet. Alle Extraktionsalveolen wurden mit einem bovinen Knochentransplantat (kleines Granulat) gefüllt und versiegelt. Kontrolluntersuchungen fanden unmittelbar postoperativ (Tag 0) sowie nach 3, 7, 15, 30, 60, 90 und 120 Tagen statt. Nach 180 Tagen wurden vor der Implantatinsertion Gewebeproben für eine histologische Analyse entnommen. Außerdem wurden während der ersten 7 postoperativen Tage qualitative Informationen zur subjektiven Wahrnehmung der Behandlung durch die Patienten mithilfe von VAS erhoben. Ergebnisse: In der MS-Gruppe war eine schnellere Heilung zu beobachten: Nach 60 Tagen waren alle Stellen der MS-Gruppe partiell verheilt, in der FGT-Gruppe dagegen nur fünf. Histologisch fand sich in der FGT-Gruppe ein überwiegend akutes Entzündungsgeschehen, während in der MS-Gruppe chronische Entzündungsprozesse beobachtet wurden. Die mittlere Epitheldicke betrug in der FGT-Gruppe 535,69 µm, in der MS-Gruppe 495,33 µm (p = 0,54). Innerhalb beider Gruppen fand sich eine erhebliche Varianz der Ergebnisdaten (p < 0,001). Die qualitative Auswertung der Patientenwahrnehmung ergab einen signifikant größeren Komfort in der MS-Gruppe (p < 0,05). Schlussfolgerung: Im Rahmen dieser Studie lieferten beide Techniken eine wirksame Versiegelung der Extraktionsalveolen mit einer schnelleren Wundheilung in der MS-Gruppe. Die VAS-Ergebnisse lassen auf signifikant geringere Beschwerden in der MS-Gruppe schließen. Keywords: Alveole, Chirurgie, Kollagen, Membran, Transplantat, Weichgewebe

Objective: This study aimed to compare the alveolar sealing performance between free gingival graft (FGG) and porcine collagen membrane (MS) and qualitatively assess patient-centered outcomes via a visual analog scale. Method and materials: Eighteen patients were randomly divided into control (FGG) and test (MS) groups. After extraction, all the alveoli were filled with bovine bone grafts (small granules) and sealed. Follow-up was during the immediate postoperative period and after 3, 7, 15, 30, 60, 90, and 120 days. After 180 days, before implant placement, tissue samples were obtained for histologic analysis. The epithelial tissues were morphometrically measured for each sample. Qualitative information on the patient’s perception of the treatment was collected after 7 days. Results: A faster healing was observed for the MS group. After 60 days, all the sites from the MS were partially healed, in contrast with only five from the FGG. The histologic results after 120 days showed for the FGG group a predominant acute inflammatory process, whereas chronic processes were observed for the MS group. The mean epithelial heights found for the FGG and MS were 535.69 µm and 495.33 µm, respectively (P = .54). The intragroup analysis showed significant variance among the data (P < .001) for both groups. The qualitative result showed statistically more significative comfort for the MS group (P < .05). Conclusion: Within the limitations of the study, both techniques effectively promote alveolar sealing. However, the visual analog scale result was superior and more significant for the MS group, with faster wound healing and lower discomfort. Keywords: collagen, graft, membrane, soft tissue, surgery, tooth socket

Objective: This study analyzed two xenogenous biomaterials based on deproteinized bovine bone mineral applied for maxillary sinus elevation. Method and materials: Fourteen patients were submitted to maxillary sinus augmentation with one of the following biomaterials: Criteria Lumina Bone Porous (test group) or Geistlich Bio-Oss (control group), both of large granules (1 to 2 mm). After 6 months, trephine biopsies were collected at the time of implant placement: 27 samples (11 patients) in the test group; 7 samples (3 patients) in the control group. Biopsies were analyzed by descriptive histology and histomorphometry, in which the percentages of newly formed bone, residual biomaterial particles, and connective tissue were evaluated. Results: Histomorphometry showed means for test and control groups, respectively, of 32.41% ± 9.42% and 26.59% ± 4.88% for newly formed bone, 22.89% ± 4.58% and 25.00% ± 4.81% for residual biomaterial, and 44.70% ± 9.54% and 48.41% ± 3.36% for connective tissue. There were no differences between groups (P > .05). Conclusion: This study concluded that Criteria Lumina Bone Porous presented similar histologic and histomorphometric characteristics to Geistlich Bio-Oss 6 months after sinus elevation surgery, identifying the tested biomaterial as an interesting alternative for bone augmentation in the maxillary sinus. (Quintessence Int 2021;52:248–256; doi: 10.3290/j.qi.a45601) Keywords: biomaterials, bone grafting, bone substitutes, clinical study, histomorphometry, maxillary sinus elevation

Purpose: This study aimed to evaluate the effects of leucocyte- and platelet-rich fibrin (L-PRF) on the inflammatory process, tissue repair, and expression of vascular endothelial growth factor (VEGF) on bone defects in the calvaria of rats. Materials and Methods: L-PRF was obtained from three animals submitted to cardiac puncture to prepare the membranes. Two noncritical defects with a diameter of 2 mm were created in the calvaria of 15 Wistar rats. The defects on the right side were filled with a blood clot (CTRL) and the left side with L-PRF. After 5, 15, and 30 days, the animals were euthanized and the specimens processed for histologic, histomorphometric, and immunohistochemical analyses. In order to measure the intensity of the inflammatory infiltrate and VEGF expression, scores were assigned from 0 to 3, with 0 being no expression, 1 discrete (up to 25%), 2 moderate (between 25% and 50%), and 3 intense (> 50%) expression. The area of bone neoformation at the edges of the defects was also quantified. Results: A less intense inflammatory infiltrate was observed in the defects filled with L-PRF compared with CTRL at all times analyzed (P .05). At 5 days, no bone neoformation was observed in any of the groups evaluated. After 15 and 30 days, greater bone neoformation was observed in the group treated with L-PRF compared with the CTRL group (P .05). At 15 days, 3,871.8 (1,070.15) μm² were recorded for the CTRL and 49,978.5 (14,360.7) μm² in the L-PRF. At 30 days, 62,284.5 (3,579.5) μm² were observed in the CTRL and 154,076.6 (31,464.9) μm² in the L-PRF. At all evaluated times, a lower inflammatory infiltrate was observed in the group treated with L-PRF compared with the CTRL. VEGF expression was observed in the initial phase and throughout the tissue repair process in both groups. At 5 days, there was no difference in VEGF expression between the groups. VEGF was present at the initial phase and throughout the tissue repair process in both groups. In the L-PRF group, a decrease in VEGF expression was observed at 15 and 30 days compared with the CTRL group. Conclusion: L-PRF had a positive effect on the regenerative process of bony defects, with a reduced inflammatory response and greater bone neoformation. Keywords: bone regeneration, fibrin, L-PRF, platelet-derived growth factor, VEGF

Der Beitrag stellt anhand eines komplexen Patientenfalls mit großen ästhetischen und funktionellen Defiziten eine multidisziplinäre konservative und schonende Methode vor, bei der durch eine breit angelegte interdisziplinäre Behandlungsplanung und Umsetzung sowohl Funktion als auch Ästhetik unter Unversehrtheit der gesunden Zahnsubstanz wiederhergestellt werden konnten. Keywords: Ästhetik, multidisziplinäre Behandlungsplanung, Zahntechnik interdisziplinär, Diastema, Zahnnichtanlage, Kieferorthopädie, Implantatprothetik, Funktion, Veneers