Finishing and polishing systems influence the roughness and color stability of acrylic and bis-acryl composite resins.

Background: To evaluate the effect of different finishing and polishing systems on the surface roughness and color changes of bis-acryl (Protemp 4 - 3M ESPE- St. Paul, USA; Structur 3 - Voco, Cuxhaven, Germany) and chemically activated acrylic materials (Duralay - Reliance, SP, Brazil). Material and Methods: Specimens (10 x 2 mm) thick were prepared for each material. The specimens were subjected to polishing and finishing procedures with aluminum oxide discs (Diamond Master - FGM, Joinville, Santa Catarina, Brazil) and spiral rubber disks (Sof-Lex - 3M ESPE, Germany). The control did not receive any polishing and finishing procedures. Surface roughness and color measurement values were obtained after the finishing and polishing procedures and immediately after 30 days of storage in water, coffee, and red wine. Data for each material were analyzed by One-Way ANOVA (p<0.05). Results: The polishing with aluminum oxide discs was able to affect the initial surface roughness values of chemically activated acrylic material (p<0.05). After immersion in staining solutions, lower ∆E values were only observed for the bis-acryl composite resins compared to the control group (p<0.05). Conclusions: The finishing and polishing systems influenced the surface roughness and color stability of the materials tested. The chemically activated acrylic resin showed lower surface roughness and higher color stability than the bis-acryl materials. Key words:Acrylic resin, bis-acryl resin, provisional restoration.

Collagen Matrix for Increasing Peri-implant Mucosal Thickness in Smokers: A Prospective Case Series.

This prospective case series aimed to evaluate the feasibility of using a volume collagen matrix for soft tissue augmentation to increase mucosal thickness in single implants in smokers who consume more than 10 cigarettes per day. Participants had single submerged implants necessitating soft tissue thickening. Soft tissue augmentation was done using a collagen matrix in the second-stage surgery. The primary outcome was soft tissue thickness at 90 days post-surgery. Secondary outcomes included median thickness at 30 and 60 days, changes in buccal soft tissue profile (digital measurements) at 30, 60, and 90 days, and oral health-related quality of life using OHIP-14 up to 90 days post-surgery. Pain levels via VAS scale and adverse effects were also assessed. Ten participants (4 men, 6 women) aged 45.2 ± 13.18 years initially smoked 10-20 cigarettes daily (average: 14.70 ± 3.47 cigarettes/day). After 90 days, median soft tissue thickness increased to 3.00 (2.00;3.00) mm. Buccal soft tissue profile (median change in ROI) increased by 0.40 (0.25;0.62) mm at 90 days. Pain levels decreased, and oral health-related quality of life improved significantly. No complications were reported. The collagen matrix significantly augmented buccal soft tissue thickness at implant sites in smokers (>10 cigarettes/day), with favorable outcomes and no complications.

Titanium dioxide nanotubes applied to conventional glass ionomer cement influence the expression of immunoinflammatory markers: An in vitro study.

Objectives: To assess the impact of different concentrations TiO2-nt incorporated into a glass ionomer cement on the proliferation, mitochondrial metabolism, morphology, and pro- and anti-inflammatory cytokine production of cultured fibroblasts (NIH/3T3), whether or not stimulated by lipopolysaccharides (LPS-2 µg/mL, 24 h). Methods: TiO2-nt was added to KM (Ketac Molar EasyMix™, 3 %, 5 %, 7 % in weight); unblended KM was used as the control. The analyses included: Cell proliferation assay (n = 6; 24/48/72h); Mitochondrial metabolism assay (n = 6; 24/48/72h); Confocal laser microscopy (n = 3; 24/48/72h); Determination of biomarkers (IL-1ß/IL-6/IL-10/VEGF/TNF) by using both multiplex technology (n = 6; 12/18 h) and the quantitative real-time PCR assay (q-PCR) (n = 3, 24/72/120 h). The data underwent analysis using both the Shapiro-Wilk and Levene tests, and by generalized linear models (α = 0.05). Results: It demonstrated that cell proliferation increased over time, regardless of the presence of TiO2-nt or LPS, and displayed a significant increase at 72 h; mitochondrial metabolism increased (p < 0.05), irrespective of exposure to LPS (p = 0.937); no cell morphology changes were observed; TiO2-nt reverted the impact of KM on the secreted levels of the evaluated proteins and the gene expressions in the presence of LPS (p < 0.0001). Conclusions: TiO2-nt did not adversely affect the biological behavior of fibroblastic cells cultured on GIC discs.

Use of Local Melatonin with Xenogeneic Bone Graft to Treat Critical-Size Bone Defects in Rats with Osteoporosis: A Randomized Study.

The aim of this study was to evaluate the effect of local administration of melatonin (MLT) on molecular biomarkers and calvaria bone critical defects in female rats with or without osteoporosis, associated or not with a xenogeneic biomaterial. Forty-eight female rats were randomly divided into two groups: (O) ovariectomized and (S) placebo groups. After 45 days of osteoporosis induction, two critical-size defects (5 mm diameter) were created on the calvaria. The groups were subdivided according to the following treatment: (C) Clot, MLT, MLT associated with Bio-Oss® (MLTBO), and Bio-Oss® (BO). After 45 days, the defect samples were collected and processed for microtomography, histomorphometry, and biomolecular analysis (Col-I, BMP-2, and OPN). All animals had one femur harvested to confirm the osteoporosis. Microtomography analysis demonstrated a bone mineral density reduction in the O group. Regarding bone healing, the S group presented greater filling of the defects than the O group; however, in the O group, the defects treated with MLT showed higher mineral filling than the other treatments. There was no difference between the treatments performed in the S group (p = 0.05). Otherwise, O-MLT had neoformed bone higher than in the other groups (p = 0.05). The groups that did not receive biomaterial demonstrated lower levels of Col-I secretion; S-MLT and S-MLTBO presented higher levels of OPN, while O-C presented statistically lower results (p < 0.05); O-BO showed greater BMP-2 secretion (p < 0.05). In the presence of ovariectomy-induced osteoporosis, MLT treatment increased the newly formed bone area, regulated the inflammatory response, and increased OPN expression.

Microbiological analysis of tongue dorsum coating in patients hospitalized in ICU / Análise microbiológica da saburra em dorso lingual de pacientes internados em UTI

ABSTRACT Objective: ssess quantitatively and qualitatively tongue coating microbiota in ICU patients. Methods: Analytical observational study, convenience sample comprising 65 patients was included for medical report analysis and collection of general data, tongue coating assessment through visual inspection and microbiological sample collection for further laboratory analysis. The collection was performed by a single examiner using a sterile swab introduced and rubbing the posterior portion of the tongue close to the oropharynx. Results: Most patients (60%) belonged to the female sex, at mean age of 74.2 years. The main reasons for hospitalization were lung issues (26.2%) - prevailing associated comorbidities were diabetes (43.1%) and high blood pressure (66.2%). The mean length of stay in the ICU was one day. All patients presented tongue dorsum coating. There were Candida albicans (37%), Streptococcus parasanguinis (26.1%) and Streptococcus mitis (32.6%) in 1/3 of lingual extension. Streptococcus mitis (p=0,0265) was the most prevalent species. Conclusion: There was no significance between the amount of coating and number of observed species, although all assessed patients had presented coating. The most prevalent microorganisms were Candida albicans, Streptococcus parasanguinis and Streptococcus mitis.

RESUMO Objetivo: Avaliar quantitativa e qualitativamente a microbiota da saburra lingual em pacientes internados em UTI. Métodos: Estudo observacional analítico, amostra de conveniência composta por 65 pacientes para análise de laudo médico e coleta de dados gerais, avaliação da saburra lingual por inspeção visual e coleta de amostra microbiológica para posterior análise laboratorial. A coleta foi realizada por um único examinador por meio de swab estéril introduzida e fricção na porção posterior de língua próxima à orofaringe. Resultados: A maioria dos pacientes (60%) pertencia ao sexo feminino, com média de idade de 74,2 anos. Os principais motivos de internação foram problemas pulmonares (26,2%) - as comorbidades associadas predominantes foram diabetes (43,1%) e hipertensão arterial (66,2%). O tempo de internação médio na UTI foi de um dia. Todos os pacientes apresentavam saburra do dorso da língua. Havia Candida albicans (37%), Streptococcus parasanguinis (26,1%) e Streptococcus mitis (32,6%) em 1/3 da extensão lingual. Streptococcus mitis (p=0,0265) foi a espécie mais prevalente. Conclusões: Não houve significância entre a quantidade de recobrimento e o número de espécies observadas, embora todos os pacientes avaliados tenham apresentado recobrimento. Os microrganismos mais prevalentes foram Candida albicans, Streptococcus parasanguinis e Streptococcus mitis.

Root coverage of multiple gingival recessions treated with coronally advanced flap associated with xenogeneic acellular dermal matrix or connective tissue graft: a 6-month split-mouth controlled and randomized clinical trial.

OBJECTIVES: This study aimed to compare xenogeneic dermal matrix (XDM) to connective tissue graft (CTG) associated with coronally advanced flap (CAF) in treating Miller's class I and II (RT1) multiple gingival recession in a split-mouth randomized clinical trial. MATERIALS AND METHODS: Fifteen patients with bilateral Miller's class I and II multiple recessions were selected. The patient's side receiving each treatment was randomly allocated to receive XDM or CTG. The clinical parameters were measured at baseline and 6 months of follow-up. RESULTS: At 6 months, no significant difference in the root coverage (RC) (95.28 ± 6.89% for CTG and 92.68 ± 7.35% for XDM) and the keratinized tissue (KT) gain (0.91 ± 0.46 mm for CTG and 0.74 ± 0.39 mm for XDM) was observed between groups (p > 0.05). The CTG group presented higher complete root coverage (CRC) than XDM (60% and 33%, respectively) (p = 0.045). Multiple logistic regression indicated that the XDM (p = 0.01) and the XDM and KT interaction (p = 0.02) negatively interfered in the CRC. A 1-mm increase in the baseline KT when using XDM increases almost 6 times the chance of achieving CRC, and XDM reached a similar CRC probability to CTG when the receptor area presented at least 2 mm of KT. CONCLUSIONS: Both treatments were effective for treating multiple gingival recession; similar KT gain, GR reduction, and RC were obtained for CTG and XDM, while CTG promoted higher CRC than XDM. Moreover, the amount of KT at baseline was determinant for CRC when treating multiple gingival recession with XDM. CLINICAL RELEVANCE: XDM produces limited CRC in sites with a reduced amount of KT. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (REBEC) number RBR-56NZQ6.

Histologic and histomorphometric analysis of two biomaterials of xenogenous origin for maxillary sinus elevation: a clinical study.

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.

Inflammatory cell profile using different autologous fibrin protocols.

Autologous fibrin has been widely used in surgical procedures for both soft and hard tissue repair. There are different protocols and devices to obtain this matrix, with varying centrifugal time, gravity force, speed, angle of the sample tube and spinning radius. The aim of this study was to compare three methods of obtaining autologous fibrin: L-PRF using the Intra-Spin L-PRF centrifuge (Dohan protocol), the advanced PRF (A-PRF) using the Intra-Spin L-PRF centrifuge and autologous leukocyte fibrin (ALF), using the Kasvi centrifuge. Venous blood was collected from 7 healthy volunteers, which were submitted to the 3 different methods of centrifugation. The membranes were tissue-processed and evaluated by immunohistochemistry for CD3, CD20, CD68 and CD138. For CD68+, a lower number of cells was immunolabelled in the L-PRF group when compared to the other groups (A-PRF and ALF). For CD3+, a lower number of immunolabellated cells was observed in the ALF group when compared to the remaining groups (p < 0.05). In the A-PRF group, the CD20+ cell count was lower than in the remaining groups. No difference was observed in CD138+ cell counts between the groups. The 3 protocols tested are suitable for obtaining autologous fibrin membranes.

DC-STAMP and TACE Levels are Higher in Patients with Periodontitis.

Although periodontitis is one of the commonest infectious inflammatory diseases in humans, the mechanisms involved with its immunopathology remain ill understood. Numerous molecules may induce inflammation and lead to bone resorption, secondary to activation of monocytes into osteoclasts. TACE (TNF-α converting enzyme) and DC-STAMP (dendritic cell-specific transmembrane protein) appear to play a role on bone resorption since TACE induces the release of sRANKL (soluble receptor activator of nuclear factor kappa-ß ligand) whereas DC-STAMP is a key factor in osteoclast induction. The present study evaluated the levels of TACE and DC-STAMP in patients with and without periodontitis. Twenty individuals were selected: 10 periodontally healthy participants undergoing gingivectomy for esthetic reasons and 10 diagnosed with periodontitis. Protein levels of such molecules in gingival tissue were established using Western blotting. Protein levels of both TACE and DC-STAMP were higher in the periodontitis group than in the control group (p<0.05; Student t-test). In conclusion, TACE and DC-STAMP protein levels are elevated in patients with periodontitis, favoring progression of bone resorption.

Preliminary findings on the possible role of B-lymphocyte stimulator (BLyS) on diabetes-related periodontitis.

The possible role of B-cell growth and differentiation-related cytokines on the pathogenesis of diabetes-related periodontitis has not been addressed so far. The aim of this study was to evaluate the effects of diabetes mellitus (DM) on the gene expression of proliferation-inducing ligand (APRIL) and B-lymphocyte stimulator (BLyS), two major cytokines associated to survival, differentiation and maturation of B cells in biopsies from gingival tissue with periodontitis. Gingival biopsies were obtained from subjects with periodontitis (n = 17), with periodontitis and DM (n = 19) as well as from periodontally and systemically healthy controls (n = 10). Gene expressions for APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were evaluated using qPCR. The expressions APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were all higher in both periodontitis groups when compared to the control group (p < 0.05). Furthermore, the expressions of BLyS, TRAP and RANKL were significantly higher in the subjects with periodontitis and DM when compared to those with periodontitis alone (p < 0.05). The mRNA levels of BLyS correlated positively with RANKL in the subjects with periodontitis and DM (p < 0.05). BLyS is overexpressed in periodontitis tissues of subjects with type 2 DM, suggesting a possible role of this cytokine on the pathogenesis DM-related periodontitis.

Lithium chloride improves bone filling around implants placed in estrogen-deficient rats.

OBJECTIVE: This study evaluated the ability of lithium chloride (LiCl) to increase bone filling (BF) around threaded titanium implants inserted in estrogen-deficient rats and, thein-vitro effects of this drug on osteoblast-like cell viability, proliferation, mineralization and expression of bone-related markers. DESIGN: In vivo: Rats received sham surgery plus water (Estrogen-sufficient group), ovariectomy plus water (Estrogen-deficient group) or ovariectomy plus LiCl (150 mg/kg/every other day) (LiCl/estrogen-deficient group). On the 21st day after ovariectomy/sham surgeries, a threaded titanium implant was inserted in the rat tibia. BF and the number of TRAP + cells were assessed at 10, 20 and 30 days after implant placement. In vitro: Osteosarcoma SAOS-2 cells were exposed to 0, 0.01, 0.05, and 0.1 mM of LiCl; cell proliferation, viability, mineralization (alizarin red staining) and gene expressions of RUNX-2, OCN, OPN, BSP and ALP (Real Time PCR) were estimated in the cultures. RESULTS: In vivo: The estrogen-sufficient and LiCl/estrogen-deficient groups demonstrated higher percentages of BF, within the limits of implant threads, than the estrogen-deficient group at 20 and 30 days (p < 0.05). The number of TRAP + cells was lower in LiCl/estrogen-deficient than in the estrogen-deficient group at all experimental times (p < 0.05). In vitro: Cell cultures exposed to LiCl (0.01 or 0.05 mM) exhibited larger areas of mineralized matrix than the non-exposed cultures (p < 0.05) and demonstrated the highest expressions of the genes investigated. CONCLUSION: LiCl treatment improved BF around threaded titanium implants inserted in estrogen-deficient rats and stimulated matrix mineralization and overexpression of bone-formation markers in osteoblastic cells in culture.

Viability and collagen secretion by fibroblasts on titanium surfaces with different acid-etching protocols.

BACKGROUND: From the consolidation of surface treatments of dental implants and knowledge on the cellular mechanisms of osseointegration, studies have highlighted the importance of a connective tissue seal against the implant to prevent contamination from the oral environment and consequent biofilm formation. OBJECTIVE: This in vitro study aimed to evaluate whether different titanium surface treatments using acid solutions promoted an increase in collagen secretion, proliferation, and viability of fibroblasts. MATERIAL AND METHODS: Commercially pure grade-4 titanium disks (6 × 2 mm) were treated with different acid solutions (hydrochloric, nitric, and sulfuric) for 20 and 60 min, respectively, obtaining mean surface roughness of 0.1 to 0.15 µm and 0.5 to 0.7 µm. Human fibroblasts were seeded onto different surfaces and assessed after 24 h, 48 h, and 72 h for cell proliferation and viability using Trypan blue staining and MTT, respectively, as well as the secretion of type I collagen on to such surfaces using ELISA. Machined titanium surfaces were used as controls. Data were statistically analyzed using one-way ANOVA and Fisher's LSD test for multiple comparisons, adopting a significance level of 5%. RESULTS: No significant difference was observed in cell proliferation for the different surfaces analyzed. Cell viability was significantly lower on the machined surface, after 48 h, when compared to the groups treated with acid for 20 or 60 min, which did not differ from each other. The expression of type I collagen was lowest on the acid-treated surfaces. CONCLUSION: The results showed that the acid treatment proposed did not promote fibroblast proliferation and viability nor favor type I collagen synthesis.

Avaliação do efeito de cepas probióticas em biofilme de S. aureus sobre discos de titânio com superfície tratada / Assessment of probiotic bacterial strains effect on S. aureus biofilm on titanium discs with treated surfaces

Resumo Introdução As doenças peri-implantares apresentam como um dos principais fatores etiológicos o biofilme bacteriano, geralmente formado por uma microbiota semelhante à das doenças periodontais. Seu tratamento está centrado na descontaminação da superfície do implante e na remoção mecânica do biofilme, podendo ainda estar associado à administração de agentes antimicrobianos. Nesse sentido, tem sido cogitada a utilização de probióticos, que são microrganismos benéficos à saúde e que podem ter grande importância na cavidade oral, como coadjuvante no tratamento das peri-implantites. Objetivo Avaliar o efeito das cepas probióticas de Lactobacillus brevis e Bifidobacterium bifidum no crescimento do biofilme monoespécie de Staphylococcus aureus. Material e método Discos de titânio padronizados e com superfície tratada foram submersos em meio contendo caldo BHI e Staphylococcus aureus durante sete dias. Após esse período, o caldo foi retirado, os discos foram lavados e, então, introduzidos em um novo caldo BHI contendo as suspensões probióticas, sendo assim comparados a um grupo controle, sem probióticos. As amostras foram incubadas por 24h e então foram realizadas as diluições e a contagem das UFC (unidades formadoras de colônia) para Staphylococcus aureus. Resultado Após análise estatística dos dados, observou-se que a adição de ambos os probióticos resultaram em redução significativa (p<0,05) de UFC, quando comparados ao controle. Conclusão Conclui-se que os probióticos analisados (Lactobacillus brevis e Bifidobacterium bifidum) reduziram consideravelmente o crescimento do patógeno Staphylococcus aureus. Além disso, a cepa de Lactobacillus brevis apresentou efeito inibidor superior ao da cepa Bifidobacterium bifidum para ser utilizada como controle do biofilme bacteriano de Staphylococcus aureus.

Abstract Introduction One of the main etiological factors for peri-implant diseases is the bacterial biofilm, which usually features a similar microbiota to periodontal diseases. Its treatment focus on the decontamination of the implant surface and on the mechanical removal of biofilm, and it may also be associated to the administration of antimicrobial agents. Thus, the use of probiotics has been considered, since they feature beneficial microorganisms to health and may be of great importance for the oral cavity as an adjunct for the treatment of peri-implant diseases. Objective The aim of this in vitro study was to assess the effect of probiotic strains of Lactobacillus brevis and Bifidobacterium bifidum on the growth of single-species biofilm of Staphylococcus aureus. Material and method Standardized surface-treated titanium discs were submerged in a medium containing BHI broth and Staphylococcus aureus, for 7 days. After this period, the broth was removed, the discs were washed and, then, submerged in a new BHI broth containing probiotic suspensions and compared to a control group (with no probiotics). Samples were incubated for 24 hours and then the dilutions and CFU (colony-forming units) counting for Staphylococcus aureus were performed. Result Statistical analysis revealed that the addition of both probiotics resulted in a significant reduction (p<0,05) of CFU, when compared to the control group. Conclusion The assessed probiotics (Lactobacillus brevis and Bifidobacterium bifidum) considerably reduced Staphylococcus aureus growth. In addition, Lactobacillus brevis strain presented a superior inhibition effect than Bifidobacterium bifidum strain for Staphylococcus aureus bacterial biofilm control.

Clinical outcomes of peri-implantitis treated with bone substitute and resorbable membrane: a literature review with a systematic approach / Desfechos clínicos do tratamento da peri-implantite com substituto ósseo e membrana reabsorvível: revisão da literatura com abordagem sistemática

ABSTRACT Objective: The objective of this review was to evaluate the outcomes of the treatment of peri-implant defects, using Guided Bone Regeneration. Methods: A literature search was performed based on the PICO methodology in the PubMed/Medline, SciELO, Lilacs electronic databases, CAPES periodicals and the Cochrane Library. We included studies using bovine mineral matrix, associated to a collagen membrane for the treatment of peri-implantitis by Guided Bone Regeneration. Results: Of 1,163 studies, 10 were included in this review after applying the evaluation criteria. A total of 269 implants were treated in 260 patients. The follow-up period ranged from 6 to 48 months. The studies evaluated outcome in terms of reduction in probing depth, gain of clinical attachment and healing of the bony defect. Due to the heterogeneity of the studies, it was not possible to perform meta-analysis. Conclusion: Treatment of peri-implant lesions with Guided Bone Regeneration is a viable modality of treatment, providing reduction in bleeding on probing, as well as gain of clinical attachment. Complete filling of the defect is, however, an unpredictable result.

RESUMO Objetivo: O objetivo desta revisão sistemática foi avaliar os desfechos do tratamento dos defeitos peri-implantares, por meio da técnica da Regeneração Óssea Guiada. Métodos: Uma pesquisa bibliográfica, baseada na metodologia PICO, foi realizada nas bases de dados eletrônica PubMed/Medline, SciELO, Lilacs periódicos Capes e Cochrane Library. Foram incluídos estudos que utilizaram matriz mineral bovina, associado a uma membrana de colágeno para o tratamento da peri-implantite por Regeneração Óssea Guiada. Resultados: De 1.163 estudos, 10 foram incluídos nesta revisão, após aplicação dos critérios de avaliação. Um total de 269 implantes foram tratados em 260 pacientes. O período de acompanhamento variou de 6 a 48 meses. Os estudos avaliados reportaram redução média da profundidade de sondagem, ganho de inserção clínica e preenchimento ósseo do defeito. Devido à heterogeneidade dos estudos não foi possível realizar metanálise. Conclusão: O tratamento das lesões peri-implantares, com a técnica da Regeneração Óssea Guiada é uma modalidade viável de tratamento, proporcionando redução do sangramento à sondagem, bem como o ganho de inserção clínica. Porém, o completo preenchimento do defeito, é um resultado imprevisível.

Histologic Evaluation of Leucocyte- and Platelet-Rich Fibrin in the Inflammatory Process and Repair of Noncritical Bone Defects in the Calvaria of Rats.

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.

Effect of a single-tufted toothbrush on the control of dental biofilm in orthodontic patients: A randomized clinical trial.

OBJECTIVE: To compare the effect of a single-tufted toothbrush combined or not with a conventional toothbrush to control dental biofilm in healthy orthodontic patients. MATERIALS AND METHODS: Twenty orthodontic patients were randomly assigned to receive three different treatments: Group 1-conventional toothbrush; Group 2-single-tufted toothbrush and Group 3-combination of single-tufted and conventional toothbrushes. Stained plaque index (SPI), visible plaque index (VPI) and gingival bleeding index (GBI) were recorded. The data were analysed by Kolmogorov-Smirnov test. Wilcoxon test was used for intragroup comparison and Friedman test for the intergroup comparison (α = 5%). RESULTS: Intragroup analysis showed that VPI and SPI significantly decreased (P < 0.05) after 72 hour in Group 3. Anterior and posterior teeth did not show any significant statistical differences after 72 hour (P > 0.05), but VPI values in the labial surfaces were different to Group 3 (P < 0.05) in comparison with the other groups after 72 hour. Group 3 showed a statistically significant reduction (P < 0.05) for SPI in the interproximal surfaces when compared with Group 1. CONCLUSION: The combination of single-tufted and conventional toothbrushes was effective for controlling dental biofilm formation in orthodontic patients.

Influence of Transmucosal Height on Loss of Prosthetic Abutment Torque After Mechanical Cycling.

The aim of this study was to measure and record the universal transmucosal abutment height, and then evaluate whether it influenced loosening of the abutment screw by analyzing the torque and detorque values after mechanical cycling. Thirty-six implants, model CM Unitite, with internal conical connections (3.5 × 10 mm) and respective universal prosthetic abutments (n = 36, 3.25 × 6 mm), were divided into three groups (n = 12 each) with respective transmucosal heights of 0.8, 3.5, and 5.5 mm. Insertion torque of 20 Ncm was used in accordance with the manufacturer's specifications. Afterward, the samples were submitted to fatigue tests consisting of 500,000 cycles at a frequency of 2Hz, a dynamic compressive load of 120N, and an angle of 30°. The detorque values were measured with a digital torque meter and tabulated to perform statistical analyses; a level of significance of 5% was adopted. The mean detorque values (SD) obtained were 22.83 (6.30), 22.5 (5.45), and 19.41 (4.69) Ncm for transmucosal abutments with heights of 0.8, 3.5, and 5.5 mm, respectively, and showed no statistically significant difference ( P = .262). The authors of this study concluded that the transmucosal height of prosthetic abutments submitted to mechanical fatigue did not influence the detorque values.

Locally applied statins as adjuvants to non-surgical periodontal treatment for chronic periodontitis: a systematic review and meta-analysis.

OBJECTIVE: This review aimed at evaluating the effects of chronic periodontitis (CP) treatment with local statins as adjuncts to scaling and root planing (SRP), compared with SRP alone or with placebo. METHODS: Electronic and hand searches were conducted in three databases to select randomized controlled trials (RCTs) comparing SRP + statins versus SRP alone. Random effects models were conducted to determine the clinical attachment level (CAL) gain as the primary outcome variable, and probing pocket depth (PPD) reduction, modified sulcus bleeding index (mSBI), and intrabony defect depth (IBD) as the secondary outcomes. RESULTS: Of the 526 papers identified, 15 articles met the criteria for inclusion in this systematic review, and 13 in the meta-analysis. The meta-analysis showed a statistically significant CAL gain (mean differences [MD] = 1.84 mm, 95% confidence interval [CI] = 1.45 to 2.23; p = 0.000), PPD reduction (MD = 1.69 mm, 95% CI = 1.37 to 2.04; p = 0.000), mSBI change (MD = 0.70, 95% CI = 0.57 to 0.84; p = 0.000), and IBD (MD = 1.48, 95% CI = 1.30 to 1.67; p = 0.000) attributed to SRP + statin treatment (6 months). CONCLUSION: Within the limitations of this study, the collective evidence emerging from this systematic review and meta-analysis may support the use of locally applied statins as adjuncts to SRP in CP treatment, based on being an easy, low-cost alternative, with lesser adverse effects on bacterial resistance. These results should be interpreted with caution. CLINICAL RELEVANCE: Clinicians might consider the use of SRP + statins as an adjunct over other alternative approaches, based on the results of the present review. The informed decision should be taken, considering the patient's values and preferences, and the intervention to be implemented by the clinician.

Managing bisphosphonate-related osteonecrosis of the jaws with xenografts: a case report.

It is possible to manage large bone destruction induced by BRONJ using xenograft grafting to promote a bone formation.

Microbiological Sealing Analysis of a Tapered Connection and External Hexagon System.

Considering the variety of implant connection systems available in the market and the contrasting literature regarding tapered connection systems in terms of bacterial leakage, the aim of this in vitro study was to compare the effectiveness of the bacterial seal at the implant/abutment interface between an external hexagon and a tapered connection system. Twelve sets of indexed tapered connection components and twelve sets of external hexagon connection components were used for microbiological analysis. In addition, for each model, an implant with its respective prosthetic abutment was used as a negative control and another as a positive control of microbial contamination. Failure of the abutment/implant interface seal was observed via turbidity or presence of deposits in the culture. Descriptive analysis of the data and relative frequency (percentage) as well as Fisher's exact test were used at a significance level of 5%. Two of ten (20%) external hexagon specimens showed contamination against 0/10 (0%) tapered connection implants. In conclusion, both implant/abutment connections were able to prevent bacterial leakage in vitro.