Abstract Studies have highlighted numerous benefits of ozone therapy in the field of medicine and dentistry, including its antimicrobial efficacy against various pathogenic microorganisms, its ability to modulate the immune system effectively, reduce inflammation, prevent hypoxia, and support tissue regeneration. However, its effects on dental extraction healing remain to be elucidated. Objective Therefore, this study aimed to evaluate the effects of systemically administered ozone (O3) at different doses in the healing of dental extraction sockets in rats. Methodology To this end, 72 Wistar rats were randomly divided into four groups after extraction of the right upper central incisor: Group C – control, no systemic treatment; Group OZ0.3 – animals received a single dose of 0.3 mg/kg O3; Group OZ0.7 – a single dose of 0.7 mg/kg O3; and Group OZ1.0 – a single dose of 1.0 mg/kg O3, intraperitoneally. In total, six animals from each group were euthanized at 7, 14, and 21 days after the commencement of treatment. Bone samples were harvested and further analyzed by descriptive histology, histomorphometry, and immunohistochemistry for osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) protein expression. Results All applied doses of O3 were shown to increase the percentage of bone tissue (PBT) after 21 days compared to group C. After 14 days, the OZ0.7 and OZ1.0 groups showed significantly higher PBT when compared to group C. The OZ1.0 group presented the most beneficial results regarding PBT among groups, which denotes a dose-dependent response. OCN immunostaining was higher in all groups at 21 days. However, after seven and 14 days, the OZ1.0 group showed a significant increase in OCN immunostaining compared to C group. No differences in TRAP+ osteoclasts were found between groups and time points. Conclusion Therefore, O3 therapy at higher doses might be beneficial for bone repair of the alveolar socket following tooth extraction. dentistry microorganisms effectively inflammation hypoxia regeneration However elucidated Therefore O (O3 end 7 incisor control treatment OZ03 OZ OZ0 3 OZ0. 03 0 0. mgkg mg kg OZ07 07 OZ10 OZ1 OZ1. 10 1 1. intraperitoneally total 2 histology histomorphometry (OCN tartrateresistant tartrate resistant TRAP (TRAP expression (PBT dosedependent dependent response points (O

Abstract Objective the aim of this study was to analyze the influence of ozone therapy (OZN) on peri-implant bone repair in critical bones by installing osseointegrated implants in the tibia of ovariectomized rats. Methodology ovariectomy was performed on 30 Wistar rats, aged six months (Rattus novergicus), and, after 90 days, osseointegrated implants were installed in each tibial metaphysis. The study groups were divided into the animals that received intraperitoneal ozone at a concentration of 700 mcg/kg — OZ Group (n=15) — and a control group that received an intraperitoneal saline solution and, for this reason, was named the SAL group (n=15). The applications for both groups occurred during the immediate post-operative period on the 2nd, 4th, 6th, 8th, 10th, and 12th day post-surgery. At various stages (14, 42, and 60 days), the animals were euthanized, and tests were performed on their tibiae. These tests include histomorphometric and immunohistochemical analyses, computerized microtomography, sampling in light-cured resin for calcified sections, and confocal microscopy. The obtained data were then analyzed using One-way ANOVA and the Shapiro-Wilk, Kruskal-Wallis, and student t-tests (P<0.05). Results our findings indicate that the OZ group (3.26±0.20 mm) showed better cellular organization and bone neoformation at 14 days (SAL group, 0.90±1.42 mm) (P=0.001). Immunohistochemistry revealed that osteocalcin labeling was moderate in the OZ group and mild in the SAL group at 14 and 42 days post-surgery. The data from the analysis of calcified tissues (microtomography, histometric, and bone dynamism analysis) at 60 days showed no statistically significant differences between the groups (P=0.32). Conclusion it was concluded that ozone therapy anticipated the initial phases of the peri-implant bone repair process. OZN (OZN periimplant peri implant rats 3 Rattus novergicus, novergicus , novergicus) 9 metaphysis 70 mcgkg mcg kg n=15 n15 n 15 (n=15 reason n=15. . postoperative post operative 2nd nd 4th th 6th 8th 10th postsurgery. postsurgery surgery. surgery post-surgery 14, (14 6 days) euthanized tibiae analyses microtomography lightcured light cured sections microscopy Oneway One way ShapiroWilk, ShapiroWilk Shapiro Wilk, Wilk Shapiro-Wilk KruskalWallis, KruskalWallis Kruskal Wallis, Wallis Kruskal-Wallis ttests t P<0.05. P005 P P<0.05 0 05 (P<0.05) 3.26±0.20 326020 26 20 (3.26±0.2 mm 1 090142 0.90±1.4 P=0.001. P0001 P=0.001 001 (P=0.001) 4 (microtomography histometric P=0.32. P032 P=0.32 32 (P=0.32) process 7 n=1 n1 (n=1 (1 P00 P<0.0 (P<0.05 3.26±0.2 32602 2 (3.26±0. 09014 0.90±1. P000 P=0.00 00 (P=0.001 P03 P=0.3 (P=0.32 n= (n= ( P0 P<0. (P<0.0 3.26±0. 3260 (3.26±0 0901 0.90±1 P=0.0 (P=0.00 P=0. (P=0.3 (n P<0 (P<0. 3.26±0 326 (3.26± 090 0.90± (P=0.0 P=0 (P=0. P< (P<0 3.26± (3.26 09 0.90 P= (P=0 (P< 3.26 (3.2 0.9 (P= (P 3.2 (3. 0. 3. (3

Resumo Este estudo teve como objetivo avaliar o impacto da atorvastatina, administrada tanto local quanto sistemicamente, em defeitos críticos na calvária de ratos. Trinta e seis ratos adultos foram randomicamente divididos em três grupos, com todos os defeitos ósseos cobertos por uma membrana de colágeno. Os grupos receberam diferentes tratamentos: água destilada (GAD), onde as membranas foram embebidas em água destilada; aplicação sistêmica de atorvastatina (GAS) numa dose de 3,6mg/kg/dia por gavagem; e aplicação local de atorvastatina (GAL). Após 14 e 28 dias, todos os animais foram sacrificados, e várias análises foram conduzidas, incluindo análise histométrica, medição do defeito residual linear, avaliação da área de osso recém-formado, determinação da área de membrana e tecido mole, contagem de células e análise imunohistoquímica. O grupo GAS apresentou uma redução significativa no defeito residual em comparação com os outros grupos (p<0.05) e um menor número de osteócitos (p<0.05) em comparação com os outros grupos. No dia 28, os grupos GAL e GAS exibiram um maior número de células inflamatórias em comparação com o GAD (p<0.05). A imunomarcação de CD31 foi semelhante para ambos os grupos, mas no caso da osteocalcina, houve um aumento significativo na marcação para os grupos GAS e GAL entre os dias 14 e 28 pós-operatórios (p<0.05). Em conclusão, a atorvastatina sistêmica demonstrou uma osteogênese aprimorada em defeitos críticos na calvária de ratos, sugerindo sua eficácia na promoção da regeneração óssea sem exercer um efeito anti-inflamatório notável. sistemicamente colágeno tratamentos GAD, , (GAD) (GAS 36mgkgdia mgkgdia 3 6mg kg mg gavagem GAL. . (GAL) 1 2 sacrificados conduzidas histométrica linear recémformado, recémformado recém formado, formado recém-formado mole imunohistoquímica p<0.05 p005 p 0 05 (p<0.05 p<0.05. CD CD3 osteocalcina pósoperatórios pós operatórios conclusão antiinflamatório anti inflamatório notável (GAD (GAL p<0.0 p00 (p<0.0 p<0. p0 (p<0. p<0 (p<0 p< (p< (p

Abstract This study aimed to evaluate the impact of atorvastatin, administered both locally and systemically, on critical defects in the calvaria of rats. Thirty-six adult rats were randomly assigned to three groups, with all bone defects covered by a collagen membrane. The groups received different treatments: distilled water (GAD), where membranes were soaked in distilled water; systemic application of atorvastatin (GAS) at a dosage of 3.6mg/kg/day through gavage; and local application of atorvastatin (GAL). After 14 and 28 days, all animals were euthanized, and various assessments were conducted, including histometric analysis, measurement of linear residual defect, evaluation of newly formed bone area, determination of membrane and soft tissue area, cell count, and immunohistochemical analysis. Group GAS exhibited a significant reduction in residual defect compared to the other groups (p<0.05) and a lower number of osteocytes (p<0.05) in comparison with other groups. On day 28, both GAL and GAS groups showed a higher number of inflammatory cells compared to GAD (p<0.05). Immunolabeling of CD31 was similar for both groups, but in the case of osteocalcin, there was a significant increase in labeling for groups GAS and GAL between days 14 and 28 postoperative (p<0.05). In conclusion, systemic atorvastatin demonstrated enhanced osteogenesis in critical calvaria defects in rats, suggesting its efficacy in promoting bone regeneration without exerting a notable anti-inflammatory effect. systemically Thirtysix Thirty six treatments GAD, , (GAD) (GAS 36mgkgday mgkgday 3 6mg kg mg gavage GAL. . (GAL) 1 2 euthanized conducted analysis area count p<0.05 p005 p 0 05 (p<0.05 p<0.05. CD CD3 osteocalcin conclusion antiinflammatory anti effect (GAD (GAL p<0.0 p00 (p<0.0 p<0. p0 (p<0. p<0 (p<0 p< (p< (p

Resumo O objetivo deste estudo foi realizar uma avaliação comparativa de dois diferentes substitutos ósseos xenogênicos na consolidação óssea de defeitos ósseos de tamanho crítico (Ø = 5 mm) criados em calvária de ratos. Trinta animais foram randomizados em 3 grupos: no grupo controle (n=10), os defeitos foram preenchidos com coágulos sanguíneos; no grupo BO (n=10), os defeitos foram preenchidos com substituto ósseo medular bovino (Bio-Oss®) e no grupo BF (n=10), os defeitos foram preenchidos com substituto ósseo cortical bovino (Bonefill®). Todos os defeitos foram cobertos com membrana absorvível. Cinco animais de cada grupo foram eutanasiados aos 30 e 45 dias de pós-operatório, logo após foram realizadas análises histomorfométricas e imuno-histoquímicas. A histomorfometria foi utilizada para mensurar a porcentagem de neoformação óssea na área total do defeito original enquanto a imunohistoquímica avaliou a expressão de imunomarcadores ósseos para proteína morfogenética óssea 2/4 (BMP2/4), osteocalcina (OCN) e fosfatase ácida resistente ao tartarato (TRAP). Todos os dados foram analisados estatisticamente com nível de significância de 5%. Os resultados demonstraram que o grupo BO apresentou maior formação óssea em comparação ao grupo BF aos 30 dias (P<0,05). No entanto, não houve diferença estatística entre os grupos controle e BO aos 30 dias (P>0,05). As expressões de OCN e BMP2/4 foram maiores no grupo BO aos 45 dias em comparação ao BF aos 30 e 45 dias respectivamente (P<0,05). Concluiu-se que mesmo com a diferença da alta expressão de proteínas relacionadas a formação óssea, ambos os biomateriais não demonstraram diferenças na indução de formação óssea após 45 dias pós-operatório. Ø mm ratos n=10, n10 n n=10 , 10 (n=10) sanguíneos BioOss® BioOss Bio Oss® Oss (Bio-Oss® Bonefill®. Bonefill Bonefill® . (Bonefill®) absorvível 4 pósoperatório, pósoperatório pós operatório, operatório pós-operatório imunohistoquímicas. imunohistoquímicas imuno histoquímicas. histoquímicas imuno-histoquímicas 24 2 2/ BMP2/4, BMP24 BMP BMP2 (BMP2/4) (OCN TRAP. TRAP (TRAP) 5% P<0,05. P005 P P<0,05 0 05 (P<0,05) entanto P>0,05. P>0,05 (P>0,05) BMP2/ Concluiuse Concluiu se pósoperatório. operatório. n1 n=1 1 (n=10 (Bio-Oss (Bonefill® (BMP2/4 (TRAP P00 P<0,0 (P<0,05 P>0,0 (P>0,05 n= (n=1 (Bonefill (BMP2/ P0 P<0, (P<0,0 P>0, (P>0,0 (n= (BMP2 P<0 (P<0, P>0 (P>0, (n (BMP P< (P<0 P> (P>0 (P< (P> (P

Abstract The purpose of this study was to provide an evaluation of two different xenogeneic bone substitutes in bone healing of critical-sized bone defects (Ø =5mm) created in rats calvaria. Thirty animals were randomized into 3 groups with one of the following treatments. In the control group (n=10), the defects were filled with blood clots; BO group (n=10), the defects were filled with bovine medullary bone substitute (Bio-Oss®); BF group (n=10), the defects were filled with bovine cortical bone substitute (Bonefill®). All defects were covered with an absorbable membrane. Five animals from each group were euthanized at 30 and 45 days, subsequently histomorphometrical and immunohistochemical analyses were performed. The histomorphometry was used to measure the percentage of new bone formation in the total area of the defect while the immunohistochemistry evaluated the expression of bone immunomarkers for bone morphogenetic protein 2/4 (BMP2/4), osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP). Data was statistically analyzed with a 5% significance level. The results demonstrated that the BO group showed greater bone formation compared to the BF group at 30 days (P<0.05). However, there was no statistically significant difference between the control and BO groups at 30 days (P>0.05). The expression of BMP2/4 and OCN were higher in the BO group at 45 days compared to the BF at 30 and 45 days respectively (P<0.05). In conclusion, even with the higher expression of proteins related to bone formation, there was no difference in new bone formation at 45 days when both anorganic bovine xenogenous grafts were evaluated. criticalsized critical sized Ø =5mm 5mm mm calvaria treatments n=10, n10 n n=10 , 10 (n=10) clots BioOss® BioOss Bio Oss® Oss (Bio-Oss®) Bonefill®. Bonefill Bonefill® . (Bonefill®) membrane 4 performed 24 2 2/ BMP2/4, BMP24 BMP BMP2 (BMP2/4) (OCN tartrateresistant tartrate resistant TRAP. TRAP (TRAP) 5 level P<0.05. P005 P P<0.05 0 05 (P<0.05) However P>0.05. P>0.05 (P>0.05) BMP2/ conclusion n1 n=1 1 (n=10 (Bio-Oss® (Bonefill® (BMP2/4 (TRAP P00 P<0.0 (P<0.05 P>0.0 (P>0.05 n= (n=1 (Bio-Oss (Bonefill (BMP2/ P0 P<0. (P<0.0 P>0. (P>0.0 (n= (BMP2 P<0 (P<0. P>0 (P>0. (n (BMP P< (P<0 P> (P>0 (P< (P> (P

Abstract Objective To assess whether bleaching gel volume influences chromatic changes, hydrogen peroxide (HP) diffusion, inflammation, and oxidative stress in the pulp tissue. Methodology A total of 60 bovine teeth were divided into four groups, according to bleaching gel volume (n=15): without gel (WG); V30 (30 µL of 35% HP); V60 (60 µL); and V120 (120 μL). HP diffusion analysis was performed in the first session (T1). Chromatic changes (ΔE, ΔE00, and WID) were assessed after the first (T1), second (T2), third (T3) sessions, and 15 d (T4) after the end of treatment. Moreover, 20 rats were randomly divided into four groups (n=10) and their upper first molars were treated with different gel volumes: control (no treatment); V2 (2 μL of 17.5% HP); V4 (4 μL); and V8 (8 μL). After 24 h, rats were euthanized and the specimens processed for histological and immunohistochemical (nitric oxide synthase) evaluation. Data were analyzed using the Wilcoxon and Mann-Whitney tests (p<0.05). Results In vitro (bovine teeth), chromatic changes were not influenced by bleaching gel volume, showing similar values in all groups and sessions, except for the control group (p<0.05). The V120 group had the highest HP diffusion values (p<0.05). In vivo (pulp tissue), the V4 and V8 groups showed the highest inflammatory infiltrate in the pulp and significant oxidative stress (p<0.05). Conclusion The adverse effects on the dental pulp related to HP diffusion, pulp inflammation, and oxidative stress depend on bleaching gel volume, while the bleaching effect is not proportional to the volume used. (HP inflammation tissue 6 n=15 n15 n (n=15) WG (WG) V V3 30 (3 35 HP) V6 (6 µL) V12 120 (12 μL. . μL) T1. T1 T (T1) ΔE, ΔE (ΔE ΔE00 WID T1, , T2, T2 (T2) T3 (T3 sessions 1 T4 (T4 treatment Moreover 2 n=10 n10 10 (n=10 volumes no treatment) ( 175 17 5 17.5 4 8 h nitric synthase evaluation MannWhitney Mann Whitney p<0.05. p005 p p<0.05 0 05 (p<0.05) teeth, teeth) tissue, tissue) used n=1 n1 (n=15 (WG 3 V1 12 (1 (T1 ΔE0 (T2 (T (n=1 17. p00 p<0.0 (p<0.05 n= (n= p0 p<0. (p<0.0 (n p<0 (p<0. p< (p<0 (p< (p

Resumo Introdução A periodontite é uma doença infecto-inflamatória, resultante da disbiose microbiana e da resposta do hospedeiro, que leva à destruição dos tecidos de suporte dentário, inclusive das fibras colágenas periodontais, podendo culminar na perda do elemento dental. Objetivo Avaliar o comportamento das fibras colágenas periodontais durante a progressão da periodontite experimental induzida em ratos. Material e método Doze ratos Wistar foram distribuídos nos grupos: Controle (C), Periodontite Experimental 14-dias (PE-14d), Periodontite Experimental 21-dias (PE-21d) e Periodontite Experimental 42-dias (PE-42d). No dia 0, os animais do grupo C foram eutanasiados. Neste mesmo dia, os animais remanescentes foram submetidos à instalação de uma ligadura de algodão ao redor do primeiro molar inferior esquerdo para indução da periodontite experimental. Tais animais foram eutanasiados aos 14 (PE-14d), 21 (PE-21d) e 42 (PE-42d) dias após a instalação da ligadura. Executou-se o processamento histológico das hemimandíbulas e as secções foram submetidas à reação histoquímica pelo vermelho picro-sirius. A análise qualitativa descritiva foi realizada sob microscopia de luz polarizada, na região de furca dental, evidenciando as fibras do ligamento periodontal. Resultado O grupo C exibiu feixes espessos e orientados de fibras colágenas maduras, condizentes com aspecto de normalidade. Os grupos com periodontite experimental exibiram desestruturação tecidual severa, com fibras colágenas imaturas e de menor espessura, sendo tais condições mais exacerbadas nos grupos PE-14d e PE-21d. Conclusão As fases iniciais da periodontite apresentam caráter agudo e, portanto, resultam na rápida destruição dos tecidos periodontais de suporte, prejudicando potencialmente a fibrilogênese e a reestruturação do colágeno no ligamento periodontal. infectoinflamatória, infectoinflamatória infecto inflamatória, inflamatória infecto-inflamatória hospedeiro dentário dental C, , (C) 14dias PE14d, PE14d PEd PE 14d d (PE-14d) 21dias PE21d 21d (PE-21d 42dias PE42d. PE42d 42d . 0 1 2 4 (PE-42d Executouse Executou se picrosirius. picrosirius picro sirius. sirius picro-sirius polarizada periodontal maduras normalidade severa espessura PE21d. 21d. PE-21d portanto (C (PE-14d

Abstract Introduction Periodontitis is an infectious-inflammatory disease resulting from microbial dysbiosis and host response that leads to the destruction of tooth support tissues, including periodontal collagen fibers, which may culminate in tooth loss. Objective To evaluate the behavior of periodontal collagen fibers during the progression of induced experimental periodontitis in rats. Material and method Twelve Wistar rats were distributed into groups: Control (C), 14-days Experimental Periodontitis (PE-14d), 21-days Experimental Periodontitis (PE-21d) and 42-days Experimental Periodontitis (PE-42d). At day 0, the animals of group C were euthanized. At the same day, the remaining animals were submitted to the installation of a cotton ligature around the lower left first molar for the induction of experimental periodontitis. The animals were euthanized at 14 (PE-14d), 21 (PE-21d) and 42 (PE-42d) days after the installation of ligature. Histological processing of the hemi-mandibles was performed and the sections underwent histochemical reaction using picro-sirius red. The descriptive qualitative analysis was performed under polarized light microscopy, in the dental furcation region, evidencing the fibers of the periodontal ligament. Result Group C exhibited thick and oriented bundles of mature collagen fibers, consistent with a normal appearance. The groups with experimental periodontitis exhibited severe tissue disruption, with immature and thinner collagen fibers, with such conditions being more exacerbated in the PE-14d and PE-21d groups. Conclusion The early stages of periodontitis present acute response, and therefore result in rapid destruction of periodontal support tissues and potentially impair fibrillogenesis and collagen restructuring in the periodontal ligament. infectiousinflammatory infectious inflammatory loss C, , (C) 14days PE14d, PE14d PEd PE 14d d (PE-14d) 21days PE21d 21d (PE-21d 42days PE42d. PE42d 42d . 0 1 2 4 (PE-42d hemimandibles hemi mandibles picrosirius picro sirius red microscopy region ligament appearance disruption (C (PE-14d

Abstract Surgical procedures, radiotherapy, and chemotherapy, individually or in association, are current oncological treatments. Among the most used chemotherapy drugs, 5-fluorouracil (5FU) is an antimetabolite with a broad spectrum of action. This study evaluated the effects of probiotics (PRO) as an adjuvant to the treatment of experimental periodontitis (EP) in rats immunosuppressed with 5FU. Methodology 108 rats were randomly allocated to six different groups: EP; SS – systemic treatment with saline solution (SS); 5FU – systemic treatment with 5FU; 5FU+PRO – systemic treatment with 5FU, followed by the local administration of Saccharomyces cerevisiae ; 5FU+SRP – systemic treatment with 5-FU, followed by scaling and root planing (SRP); and 5FU+SRP+PRO – systemic treatment with 5FU followed by local treatments with SRP and PRO. Immunosuppression was obtained at two points: at the time of ligature installation and after 48 h. Six animals from each group were euthanized at seven, 15, and 30 d and hemimandibles were collected and processed for histopathological, histometric, and immunohistochemical analysis. Data were subjected to statistical analysis (α=5%). Results At 7 d, the 5FU+PRO group showed less bone resorption and better structured connective tissue compared with the EP, SS, 5FU+SRP, and 5FU+SRP+PRO groups. At 15 d, the 5FU+SRP group showed a greater intensity of the inflammatory response (p<0.05). At 30 d, the 5FU+SRP+PRO group showed better structured bone tissue and a higher percentage of bone tissue (PBT) than the EP, SS, 5FU, and 5FU+PRO groups (p<0.05). Conclusion The use of Saccharomyces cerevisiae as monotherapy or as an adjuvant to periodontal therapy may have a positive effect on bone repair in immunosuppressed conditions. procedures radiotherapy association drugs 5fluorouracil fluorouracil 5 FU (5FU action PRO (PRO EP (EP 10 (SS) 5FUPRO FUPRO 5FUSRP FUSRP FU, 5-FU (SRP) 5FUSRPPRO FUSRPPRO points 4 h seven 3 histopathological histometric α=5%. α5 α α=5% . (α=5%) 1 p<0.05. p005 p p<0.05 0 05 (p<0.05) PBT (PBT conditions (SS (SRP α=5 (α=5% p00 p<0.0 (p<0.05 α= (α=5 p0 p<0. (p<0.0 (α= p<0 (p<0. (α p< (p<0 (p< (p

Abstract Objectives: To evaluate the influence of photobiomodulation with infrared laser (IRL) in the rat pulp tissue after bleaching, considering the immunolabeling of interleukin (IL)-23 and hypoxia-inducible factor (HIF)-1α. Methodology: The right and left molars of forty rats were divided into groups: Control – with placebo gel and Bleached – with 35% hydrogen peroxide (H2O2). Half of the rats received one IRL application on both sides, establishing a split-mouth design, which resulted in 4 groups with 20 hemi-maxillae each: Control, Bleach, IRL, and Bleached-IRL. Rats (n=10) from each group were euthanized, at 2- and 30-days mark, and the pulp tissue was evaluated using inflammation and immunolabeling scores. Wilcoxon and Mann-Whitney statistical tests were performed (p<0.05). Results: At the 2-days mark, the Bleached group had severe inflammation and necrosis in the occlusal thirds of the pulp, and moderate to severe inflammation in cervical third, whereas the Bleached-IRL had mild to moderate inflammation (p<0.05). At the 30-days mark, there was no inflammation, but tertiary dentine formation in the bleached groups. Regarding IL-23, severe immunolabeling was observed in the Bleached group (p<0.05) at the 2-days mark; at the 30-days mark, there was a reduction in immunolabeling, in which the Bleached group had moderate and the Bleached-IRL group had mild immunolabeling (p>0.05). HIF-1α was more evident at the 2-days mark in the Bleached group, without significant difference with the Bleached-IRL (p>0.05). The difference was observed between the bleached and control groups, without immunolabeling (p<0.05); at the 30-days mark, the Bleached group had reduction in HIF-1α immunolabeling, while the Bleached-IRL had an increase; the difference remained between the bleached and the controls groups (p<0.05) Conclusion: Photobiomodulation using IRL minimized the inflammation and IL-23 immunolabeling in the pulp tissue of rats after dental bleaching, but did not influence significantly the HIF-1α immunolabeling.

Abstract Objective The aim of this study was to evaluate whether probiotics multi-strain formula affects the development of apical periodontitis (AP) induced in rats. Methodology 16 Wistar rats were divided in two groups (n=8): rats with AP fed with regular diet (Control-C (CG)); rats with AP, fed with regular diet and supplemented with multi-strain formula (one billion colony-forming units (CFU)): GNC Probiotic Complex (PCG) ( Lactobacillus acidophilus, Lactobacillus salivaris, Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium bifidum, Bifidobacterium animalis subs. lactis and Streptococcus thermofilus ). AP was induced in the upper and lower first molars by dental pulp exposure to the oral environment. PCG was administered orally through gavage for 30 days during the AP development. After this period the animals were euthanized and the mandibles were removed and processed for histologic analysis, and immunochemical assays for interleukin (IL)-6, IL-10, IL-1β, RANKL, OPG, and TRAP. The Mann–Whitney U test and Student’s t test were performed (P<.05). Results The CG showed more intense inflammatory infiltrate than the PCG group (P<.05). IL-1β, IL 6 and RANKL decreased in the PCG group compared with CG (P<.05). The IL-10 level increased in the PCG group (P<.05). The OPG level was similar in both groups (P>.05). The number of mature osteoclasts (TRAP-positive multinucleated cells) was lower in PCG group when compared to the CG (P<.05). Conclusion Probiotic Complex modulates inflammation and bone resorption in apical periodontitis.

Abstract Aim To evaluate the cytotoxicity, biocompatibility and mineralization capacity of BIO-C PULPO, and MTA. Methodology L929 fibroblasts were cultured and MTT assay was used to determine the material cytotoxicity on 6, 24, and 48 h. A total of 30 male rats (Wistar) aged between 4 and 6 months, weighing between 250 and 300 g were used. Polyethylene tubes containing BIO-C PULPO, MTA, and empty tubes were implanted into dorsal connective tissue. After the experimental periods (7, 15, 30, 60, and 90 days) the tubes were histologically analyzed using hematoxylin-eosin (H&E), immunolabeling of IL-1β and TNF-α, and von Kossa staining, or without staining for polarized light analysis. The average number of inflammatory cells was quantified; the mineralization assessment was determined by the area marked in μm2 and semiquantitative immunolabeling analyses of IL-1β and TNF-α were performed. Then, data underwent statistical analysis with a 5% significance level. Results It was observed that BIO-C PULPO and MTA presented cytocompatibility at 6, 24, and 48 similar or higher than control for all evaluated period. On periods 7 and 15 days, BIO-C PULPO was the material with the highest number of inflammatory cells (p<0.05). On periods 30, 60, and 90 days, BIO-C PULPO and MTA presented similar inflammatory reactions (p>0.05). No statistical differences were found between Control, BIO-C PULPO, and MTA for immunolabeling of IL-1β and TNF-α in the different periods of analysis (p<0.05). Positive von Kossa staining and birefringent structures under polarized light were observed in all analyzed periods in contact with both materials, but larger mineralization area was found with BIO-C PULPO on day 90 (p<0.05). Conclusion BIO-C PULPO was biocompatible and induced mineralization similar to MTA.

Abstract Objective: Myofibroblasts have been associated with the development of several pathologic fibrotic conditions. This longitudinal study aims to assess the proliferative and antiapoptotic effects of cyclosporin, nifedipine and phenytoin on gingival connective tissue cells of nonhuman primate, as well as to analyze a possible role of myofibroblasts in gingival overgrowth. Materials and Methods: Gingival samples from the right superior canine area were obtained from 12 male monkeys ( Sapajus spp ) to comprise the control group. After one week, the animals were randomly assigned to three groups, which received daily oral doses of cyclosporin, nifedipine or phenytoin for 120 days. Gingival samples were collected from the left superior canine area of two animals of each group at 52 and 120 days. Histological sections were stained with hematoxylin and eosin, and immunoreacted against α-SMA, Ki- 67 and bcl-2. Results: α-SMA immunoreaction was negative in the control and experimental groups. Similarly, no difference between groups concerning immunostaining against Ki-67 and bcl-2 was observed in connective tissue cells. Conclusion: Based on this methodology, it may be concluded that gingival overgrowths induced by cyclosporin, nifedipine and phenytoin are not associated with neither myofibroblast transdifferentiation, proliferation nor apoptosis of gingival connective cells in monkeys.

Resumo O gel clareador à base de peróxido de hidrogênio (H2O2) causa danos ao tecido pulpar. Este estudo investigou a ação de um anti-inflamatório tópico, o Otosporin®, nos dentes de ratos clareados com a hipótese nula de que o Otosporin® não é capaz de minimizar a inflamação da polpa gerada pelo gel clareador. Os molares dos ratos foram divididos em grupos: ClA: clareado (H2O2 a 35% / aplicação única de 30 min); CLA-O: clareado seguido do Otosporin® (10 min); e controle: gel placebo. No segundo dia após a clareação dentária, os ratos foram mortos e suas maxilas foram processadas para análise de hematoxilina-eosina e imunohistoquímica para o fator de necrose tumoral alfa (TNF-a), interleucina (IL)-6 e IL-17. Os dados coletados foram submetidos aos testes estatísticos de Kruskal-Wallis e Dunn com um nível de significância de 5% (p<0,05). O grupo CLA apresentou inflamação moderada à severa no terço oclusal da polpa coronária, com áreas necróticas; e CLA-O, inflamação leve (p<0,05). Houve diferença significativa nos terços oclusal e médio da polpa coronária entre o grupo CLA com os grupos CLA-O e controle (p<0,05). Não houve diferença no terço cervical (p>0,05). O grupo CLA apresentou maior imunoexpressão para TNF-a comparado aos grupos CLA-O e controle (p<0,05), com imunoexpressão moderada e leve, respectivamente. Em relação a IL-6 e IL-17, o grupo CLA apresentou maior imunoexpressão comparado ao controle (p<0,05); o CLA-O foi semelhante ao controle (p>0,05). O anti-inflamatório tópico Otosporin® pode reduzir a inflamação pulpar após clareação em dentes de ratos.

Abstract Bleaching gel containing hydrogen peroxide (H2O2) cause damages in pulp tissue. This study investigated the action of a topical anti-inflammatory, the Otosporin®, in rats’ bleached teeth with the null hypothesis of which the Otosporin® is no able to minimize the pulp inflammation that bleaching gel generates. The rat’s molars were divided into groups: BLE: bleached (35% H2O2 concentration /single application of 30 min); BLE-O: bleached followed by Otosporin® (10 min); and control: placebo gel. In the second day after dental bleaching, the rats were killed, and the jaws were processed for hematoxylin-eosin and immunohistochemistry analysis for tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-17. The data collected were subjected to Kruskal-Wallis and Dunn statistical tests with at a 5% level of significance (p<0.05). The BLE group had moderate to strong inflammation in the occlusal third of the coronary pulp, with necrotic areas; and BLE-O, mild inflammation (p<0.05). There was a significant difference in the occlusal and middle thirds of the coronary pulp between the BLE with BLE-O and control groups (p<0.05). There was no difference in the cervical third (p>0.05). The BLE group had a high immunoexpression of TNF-α than BLE-O and control groups (p<0.05), with moderate and mild immunoexpression, respectively. Regarding IL-6 and IL-17, the BLE group had higher immunoexpression than control (p<0.05); the BLE-O was similar to the control (p>0.05). The topical anti-inflammatory Otosporin® can reduce pulp inflammation after dental bleaching in the rat teeth.

Abstract Objective: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces. Material and Methods: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations. The main observed alterations were related to hemodynamic pulp characteristics, such as presence of thrombosis, vascular congestion and hemorrhages. The hemodynamic alterations were statistically evaluated by Shapiro-Wilk normality test and analysis of variance by the Kruskall-Wallis test. Results: There was no significant differences observed between groups in the different types of applied forces and duration of ITM (vascular congestion, p=1.000; hemorrhage, p=0.305; thrombosis, p=1.000). Conclusions: Pulp tissue alterations resulting from ITM were limited to hemodynamic events, without progressing to irreversible degeneration, regardless of the type of force applied.

Resumo O objetivo deste estudo foi avaliar a sinalização osteoclastogenese na sutura palatina após a expansão rápida da maxila (ERM) em ratos. Um total de 30 ratos Wistar machos foram divididos aleatoriamente em dois grupos com 15 animais cada: controle (C) e grupo ERM. ERM foi realizada através da inserção de um anel de metal circular de 1,5 mm de espessura entre os incisivos superiores. Os animais foram sacrificados aos 3, 7 e 10 dias após a RME. qRT-PCR foi utilizado para avaliar a expressão de Tnfsf11 (RANKL), Tnfrsf11a (RANK) e TNFRSF11b (OPG). Os dados foram submetidos à análise de variância de duas vias, seguido pelo teste de Tukey (a=0,05). Houve uma regulação positiva de genes RANK e RANKL aos 7 e 10 dias e uma regulação positiva do gene OPG aos 3 e 7 dias de tratamento. Curiosamente, foi observado um aumento na expressão de todos os genes ao longo do tempo nos grupos ERM e C. O RANKL/OPG mostrou um aumento na sinalização favorecendo a reabsorção óssea no ERM em comparação com o C nos períodos de 3 e 7 dias. Foi observada uma sinalização contra a reabsorção óssea, assim como, uma regulação favorável da expressão do gene OPG no grupo ERM, comparado ao grupo C aos 10 dias. Os resultados deste estudo permitem concluir que o sistema RANK, RANK-L e OPG participa de remodelação óssea após a ERM.

Abstract The aim of this study was to evaluate osteoclastogenesis signaling in midpalatal suture after rapid maxillary expansion (RME) in rats. Thirty male Wistar rats were randomly assigned to two groups with 15 animals each: control (C) and RME group. RME was performed by inserting a 1.5-mm-thick circular metal ring between the maxillary incisors. The animals were euthanized at 3, 7 and 10 days after RME. qRT-PCR was used to evaluate expression of Tnfsf11 (RANKL), Tnfrsf11a (RANK) and Tnfrsf11b (OPG). Data were submitted to statistical analysis using two-way ANOVA followed by Tukey test (a=0.05). There was an upregulation of RANK and RANKL genes at 7 and 10 days and an upregulation of the OPG gene at 3 and 7 days of healing. Interestingly, an increased in expression of all genes was observed over time in both RME and C groups. The RANKL/OPG ratio showed an increased signaling favoring bone resorption on RME compared to C at 3 and 7 days. Signaling against bone resorption was observed, as well as an upregulation of OPG gene expression in RME group, compared to C group at 10 days. The results of this study concluded that the RANK, RANK-L and OPG system participates in bone remodeling after RME.

Resumo O peróxido de hidrogênio (H2O2) é capaz de penetrar pelos tecidos dentários, alterando a coloração destes, e causar danos a polpa. Este estudo avaliou a penetração por esmalte e dentina, a alteração de cor e a reposta tecidual pulpar, provocadas pelo uso de duas concentrações de H2O2 em protocolos de clareação dentária de consultório. Discos de dentes bovinos em câmaras pulpares artificiais receberam géis clareadores para avaliação da penetração por esmalte e dentina e da alteração de cor, formando os grupos: BLU (H2O2 20% - 1x50 min, Whiteness HP Blue); MAX (H2O2 35% - 3x15 min, Whiteness HP Maxx); e Controle (gel placebo - 1x50 min). A penetração por esmalte e dentina foi quantificada baseada na reação do H2O2 com o corante violeta leucocristal, e a alteração de cor foi analisada pelo sistema CIELab. Vinte ratos Wistar foram divididos em dois grupos (BLU e MAX), e tiveram os molares direito superiores tratados com os mesmos protocolos do estudo in vitro; os molares superiores do lado esquerdo serviram de controle. Após 2 dias, os animais foram eutanasiados e as maxilas examinadas por microscopia de luz. Foram atribuídos escores ao infiltrado inflamatório (1, ausente; 2, leve; 3, moderado; 4 severo ou necrose). Os dados foram submetidos a testes estatísticos (=0,05). O grupo MAX apresentou maior penetração de H2O2 por esmalte e dentina (p<0,05). A alteração de cor foi semelhante nos grupos clareados (p>0,05), mas diferente quando comparados grupos clareados com controle (p<0,05). MAX apresentou inflamação severa nos terços superiores da polpa coronária, e BLU apresentou inflamação moderada (p<0,05). Assim, protocolo para procedimento clareador de consultório utilizando baixas concentrações de H2O2 deve ser de escolha na clínica, por reduzir a penetração por esmalte e dentina, causando menos danos à polpa, e proporcionar mesma eficiência clareadora.

Abstract Hydrogen peroxide (H2O2) penetrates into the dental hard tissues causing color alteration but also alterations in pulpal tissues. Hard-tissue penetration, color alteration and the pulp response alterations were evaluated for two in-office bleaching protocols with H2O2. For trans-enamel/dentin penetration and color alteration, discs of bovine teeth were attached to an artificial pulp chamber and bleached according to the groups: BLU (20% H2O2 - 1x50 min, Whiteness HP Blue); MAX (35% H2O2 - 3x15 min, Whiteness HP Maxx); Control (1x50 min, placebo). Trans-enamel/dentin penetration was quantified based on the reaction of H2O2 with leucocrystal violet and the color analyzed by CIELab System. Twenty Wistar rats were divided into two groups (BLU and MAX) and their maxillary right molars were treated according to the same protocols of the in vitro study; the maxillary left molars were used as controls. After 2 days, the animals were killed and their maxillae were examined by light microscopy. The inflammation of pulp tissue was scored according to the inflammatory infiltrate (1, absent; 2, mild; 3, moderate; 4, severe/necrosis). Data were analyzed by statistical tests (α=0.05). MAX showed higher trans-enamel/dentinal penetration of H2O2 (p<0.05). The color alteration was similar for both groups (p>0.05), and different when compared to Control group (p<0.05). MAX showed severe inflammation in the upper thirds of the coronal pulp, and BLU showed moderate inflammation (p<0.05). In-office bleaching protocols using lower concentrations of hydrogen peroxide should be preferred due to their reduced trans-enamel/dentinal penetration since they cause less pulp damage and provide same bleaching efficiency.