Effect of two corticotomy protocols on periodontal tissue and orthodontic movement.

Objective To compare two corticotomy surgical protocols in rats to verify whether they alter conventional orthodontic movement. Methodology Sixty Wistar rats were divided into three groups - orthodontic movement (CG), orthodontic movement and corticotomy (G1) and orthodontic movement with corticotomy and decortication (G2) - and euthanized after 7 and 14 days. Tooth movement (mm), bone volume fraction and bone volume ratio to total volume (BV/TV), and bone mineral density (BMD) were evaluated by micro-CT. The total amount of bone was measured in square millimeters and expressed as the percentage of bone area in the histomorphometry. The number of positive TRAP cells and RANK/RANKL/OPG interaction were also investigated. Results Day 14 showed a statistically significant difference in orthodontic tooth movement in CG compared with G1 (7.52 mm; p=0.009) and G2 (7.36 mm; p=0.016). A micro-CT analysis revealed a difference between CG, G1 and G2 regarding BV/TV, with G1 and G2 presenting a lower BV/TV ratio at 14 days (0.77 and 0.73 respectively); we found no statistically significant differences regarding BMD. There was a difference in the total amount of bone in the CG group between 7 and 14 days. At 14 days, CG presented a significantly higher bone percentage than G1 and G2. Regarding TRAP, G2 had more positive cells at 7 and 14 days compared with CG and G1. Conclusion Corticotomy accelerates orthodontic movement. Decortication does not improve corticotomy efficiency.

Effect of two corticotomy protocols on periodontal tissue and orthodontic movement

Abstract Objective To compare two corticotomy surgical protocols in rats to verify whether they alter conventional orthodontic movement. Methodology Sixty Wistar rats were divided into three groups - orthodontic movement (CG), orthodontic movement and corticotomy (G1) and orthodontic movement with corticotomy and decortication (G2) - and euthanized after 7 and 14 days. Tooth movement (mm), bone volume fraction and bone volume ratio to total volume (BV/TV), and bone mineral density (BMD) were evaluated by micro-CT. The total amount of bone was measured in square millimeters and expressed as the percentage of bone area in the histomorphometry. The number of positive TRAP cells and RANK/RANKL/OPG interaction were also investigated. Results Day 14 showed a statistically significant difference in orthodontic tooth movement in CG compared with G1 (7.52 mm; p=0.009) and G2 (7.36 mm; p=0.016). A micro-CT analysis revealed a difference between CG, G1 and G2 regarding BV/TV, with G1 and G2 presenting a lower BV/TV ratio at 14 days (0.77 and 0.73 respectively); we found no statistically significant differences regarding BMD. There was a difference in the total amount of bone in the CG group between 7 and 14 days. At 14 days, CG presented a significantly higher bone percentage than G1 and G2. Regarding TRAP, G2 had more positive cells at 7 and 14 days compared with CG and G1. Conclusion Corticotomy accelerates orthodontic movement. Decortication does not improve corticotomy efficiency.

The influence of LLLT applied on applied on calvarial defect in rats under effect of cigarette smoke.

OBJECTIVE: Considering the global public health problem of smoking, which can negatively influence bone tissue repair, the aim of this study is to analyze the influence of photobiomodulation therapy (PBM) on calvaria defects created surgically in specimens under the effect of cigarette smoke and analyzed with use of histomorphometric and immunohistochemistry techniques. METHODOLOGY: Calvaria defects 4.1 mm in diameter were surgically created in the calvaria of 90-day-old rats (n=60) that were randomly divided into 4 experimental groups containing 15 animals each: control group (C), smoking group (S), laser group (L), and smoke associated with laser group (S+L). The animals were subjected to surgery for calvaria defects and underwent PBM, being evaluated at 21, 45, and 60 days post-surgery. The specimens were then processed for histomorphometric and immunohistochemistry analyses. The area of bone neoformation (ABN), percentage of bone neoformation (PBNF), and the remaining distance between the edges of the defects (D) were analyzed histometrically. Quantitative analysis of the TRAP immunolabeled cells was also performed. The data were subjected to analysis of variance (ANOVA) in conjunction with Tukey's test to verify the statistical differences between groups (p<0.05). RESULTS: The smoking group showed less ABN compared to the other experimental groups in all periods, and it also showed more D at 21 days compared to the remaining groups and at 45 days compared to the laser group. The smoking group showed a lower PNBF compared to the laser group in all experimental periods and compared to smoking combined with LLLT group at 21 days. CONCLUSIONS: PBM acted on bone biomodulation, thus stimulating new bone formation and compensating for the negative factor of smoking, which can be used as a supportive therapy during bone repair processes.

Macroscopic and radiographic aspects of orthodontic movement associated with corticotomy: animal study.

INTRODUCTION: To quantify the rate of tooth movement in two corticotomy protocols in an experimental model in rats through macroscopic and radiographic analysis. METHODS: The animals were divided into three groups: orthodontic movement (CO), orthodontic movement plus corticotomy surgery (G2), and orthodontic movement and corticotomy surgery with decorticalization (G3).The euthanasia occurred in 7 and 14 days. The data were statistically analyzed (p < 0.05). RESULTS: The CO presented lower distance between the mesial surface of the first molar and the distal surface of the third molar when compared to the G2 (6.96 ± 0.24, p = 0.009) and G3 (6.93 ± 0.18, p = 0.016) in the macroscopic analysis. In the 7 days, there was no statistically significant radiographic difference between the three groups: CO(0.94 ± 0.21 mm2), G2(1.05 ± 0,27 mm2), and G3(1.08 ± 0.27 mm2).There was a statistically significant difference between CO (0.87 ± 0.12 mm2), G2 (1.00 ± 0.12 mm2), and G3 (1.11 ± 0.14 mm2) at 14 days. There was a statistically significant linear difference between the groups in all periods. CONCLUSION: Tooth movement and the region of interest were influenced by corticotomy, regardless of the surgical technique in the 14 days.

The influence of LLLT applied on applied on calvarial defect in rats under effect of cigarette smoke

Abstract Objective Considering the global public health problem of smoking, which can negatively influence bone tissue repair, the aim of this study is to analyze the influence of photobiomodulation therapy (PBM) on calvaria defects created surgically in specimens under the effect of cigarette smoke and analyzed with use of histomorphometric and immunohistochemistry techniques. Methodology Calvaria defects 4.1 mm in diameter were surgically created in the calvaria of 90-day-old rats (n=60) that were randomly divided into 4 experimental groups containing 15 animals each: control group (C), smoking group (S), laser group (L), and smoke associated with laser group (S+L). The animals were subjected to surgery for calvaria defects and underwent PBM, being evaluated at 21, 45, and 60 days post-surgery. The specimens were then processed for histomorphometric and immunohistochemistry analyses. The area of bone neoformation (ABN), percentage of bone neoformation (PBNF), and the remaining distance between the edges of the defects (D) were analyzed histometrically. Quantitative analysis of the TRAP immunolabeled cells was also performed. The data were subjected to analysis of variance (ANOVA) in conjunction with Tukey's test to verify the statistical differences between groups (p<0.05). Results The smoking group showed less ABN compared to the other experimental groups in all periods, and it also showed more D at 21 days compared to the remaining groups and at 45 days compared to the laser group. The smoking group showed a lower PNBF compared to the laser group in all experimental periods and compared to smoking combined with LLLT group at 21 days. Conclusions PBM acted on bone biomodulation, thus stimulating new bone formation and compensating for the negative factor of smoking, which can be used as a supportive therapy during bone repair processes.

Influence of obesity on experimental periodontitis in rats: histopathological, histometric and immunohistochemical study.

OBJECTIVES: This study assessed the influence of obesity on the progression of ligature-induced periodontitis in rats. MATERIALS AND METHODS: Forty-eight adult Wistar rats were randomly divided into two groups: the HL group (n = 24) was fed high-fat animal food to induce obesity, and the NL group (n = 24) was fed normolipidic animal food. Obesity was induced within a period of 120 days, and the induction of experimental periodontitis (EP) was subsequently performed for 30 days. The animals were euthanized after 7, 15, and 30 days, and the jaws were removed for histopathological, histometric, and immunohistochemical analyses. Tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa beta ligand (RANKL), and osteoprotegerin (OPG) were analyzed via immunolabeling. RESULTS: Histological findings indicated that the inflammation was more extensive and lasted longer in the HL/EP; however, advanced destruction also occurred in the NL/EP. Greater bone loss was verified in the HL/EP group (2.28 ± 0.35) in the period of 7 days than in the NL/EP group (1.2 ± 0.29). High immunolabeling was identified in the HL/EP group in the initial periods for RANKL and TRAP, whereas the NL/EP group presented with moderate immunolabeling for both factors. The HL/EP and NL/EP groups showed low immunolabeling for OPG. CONCLUSIONS: Obesity induced by a high-fat diet influenced alveolar bone metabolism when associated with experimental periodontitis and caused a more severe local inflammatory response and alveolar bone loss. CLINICAL RELEVANCE: Obesity is related to greater alveolar bone loss and an accentuated local inflammatory response, which may be reflected in the clinical severity of periodontitis and dental loss.

Probiotic therapy as a novel approach in the prevention and treatment of gingivitis. a review / Terapia probiótica como uma nova abordagem na prevenção e tratamento da gengivite. Uma revisão

Objective: Gingivitis is caused by a mixture of Gram-positive and Gram-negative species and is characterized by inflammatory exudate in the marginal region. Probiotics have been introduced in the prevention and treatment of periodontal diseases and represent an innovative approach to maintaining oral health using beneficial bacteria when administered in adequate amounts. The mechanism of action of probiotics in the oral cavity is not fully understood but is commonly explained by a combination of local and systemic immunomodulation. The results of the studies suggest that probiotics may be useful in the prevention and treatment of gingivitis, but their effectiveness is still very questionable. Thus, more in vivo research is needed through randomized controlled studies evaluating the main periodontal clinical parameters, levels of inflammatory mediators and microbiological analyzes, especially to elucidate some still unknown mechanisms of action and to ensure the use of probiotics as an effective therapy in the prevention and treatment of gingivitis. (AU)

Objetivo: A gengivite é causada por uma mistura de espécies Gram-positivas e Gram-negativas e é caracterizada pelo exsudado inflamatório na região marginal. Os probióticos tem sido introduzido na prevenção e tratamento das doenças periodontais e representam uma abordagem inovadora para manter a saúde bucal através da utilização de bactérias benéficas quando administradas em quantidades adequadas. O mecanismo de ação dos probióticos na cavidade bucal não é totalmente compreendido, mas é comumente explicado por uma combinação de imunomodulação local e sistêmica. Os resultados dos estudos sugerem que os probióticos podem ser úteis na prevenção e tratamento da gengivite, porém sua eficácia é muito questionável ainda. Desta forma, são necessárias mais pesquisas in vivo através de estudos randomizados controlados avaliando os principais parâmetros clínicos periodontais, níveis de mediadores inflamatórios e analises microbiológicas, especialmente para elucidar alguns mecanismos de ação ainda desconhecido e para assegurar a utilização dos probióticos como terapia eficaz na prevenção e tratamento da gengivite.(AU)

Curcumin photodynamic effect in the treatment of the induced periodontitis in rats.

This study assessed the effect of curcumin as a photosensitizer in antimicrobial photodynamic therapy (aPDT) for the treatment of induced periodontitis in rats. Periodontitis was induced via a ligature around the mandibular first molar on the left side of 96 rats. The ligature was removed 7 days later, and the animals were randomized into four groups: NT, no local treatment; CUR, irrigation with curcumin solution (40 µM); LED, irradiation with a light-emitting diode (LED, InGaN, 465-485 nm, 200 mW/cm2, 60 s); and aPDT, irrigation with curcumin solution (40 µM) followed by irradiation with LED. Eight animals from each group were euthanized at 7, 15, and 30 days post-treatment. Treatments were assessed using alveolar bone loss (ABL) in the furcation region using histological, histometric, and immunohistochemical analyses. Rats treated with aPDT exhibited less ABL at 7 days compared to the NT group, moderate pattern immunolabeling for osteoprotegerin at 30 days, and a pattern of immunolabeling for RANKL from moderate to low. Treatments resulted in smaller numbers of TRAP-positive cells compared to the NT group. aPDT as monotherapy using curcumin as a photosensitizer and LED as the light source was effective in the treatment of induced periodontitis in rats.

Low-level laser and antimicrobial photodynamic therapy on experimental periodontitis in rats submitted to chemotherapy by 5-fluorouracil.

PURPOSE: The aim of this study was to evaluate the effects of low-level laser therapy (LLLT) and antimicrobial photodynamic therapy (aPDT) as adjuvant to mechanical treatment of experimental periodontitis (EP) in adult rats submitted to 5-fluorouracil (5-FU) chemotherapy. METHODS: EP was induced through ligature around the left mandibular first molar for 7 days. The ligature was removed and the animals separated into groups: EP, no treatment; 5FU, systemic administration of 5-FU (80 and 40 mg/kg); 5FU/scaling and root planing (SRP), systemic application of 5-FU and SRP; 5FU/SRP/LLLT, systemic application of 5-FU, SRP, and LLLT (660 nm, 0.035 W; 29.4 J/cm2); and 5FU/SRP/aPDT, systemic application of 5-FU, SRP, and aPDT (methylene blue irrigation and LLLT). The animals were euthanized 7, 15, and 30 days after treatments. Histological sections from mandibles were processed for histomorphometric and immunohistochemical analysis (TRAP, RANKL, OPG, TNF-α, IL-6, IL-10). The alveolar bone loss (BL) area in the furcation region of the mandibular first molar was analyzed histometrically. RESULTS: There was less bone loss in 5FU/SRP/aPDT compared with 5FU at 7 days (p < 0.05). The immunohistochemical analysis showed no significant difference for TRAP and osteoprotegerin, but lower RANKL immunolabeling was observed in the 5FU/SRP/LLLT and 5FU/SRP/aPDT groups compared with the 5FU group at 15 days. There was lower TNF-α and IL-6 immunolabeling in the 5FU/SRP/LLLT and 5FU/SRP/aPDT groups and higher IL-10 immunolabeling in 5FU/SRP/aPDT at 30 days. CONCLUSION: LLLT and aPDT adjuvant to SRP minimized the effects of 5-FU on periodontal disease. Furthermore, aPDT promoted greater benefits in bone loss control and inflammatory response.

Antimicrobial photodynamic therapy minimizes the deleterious effect of nicotine in female rats with induced periodontitis.

The aim of this study was to compare the use of antimicrobial photodynamic therapy (aPDT) as an adjunct to scaling and root planing (SRP) in the treatment of experimentally induced periodontitis in female rats that were systemically treated with or without nicotine. Female rats (n = 180) were divided into two groups: vehicle administration (Veh) and nicotine administration (Nic). Mini-pumps containing either vehicle or nicotine were implanted in the rats 30 days before the induction of experimental periodontitis (EP). EP was induced by placing a cotton ligature around the left mandibular first molar. After 7 days, the ligature was removed, and the rats were randomly divided into three treatment subgroups: SRP (only SRP), DL (SRP plus diode laser), and aPDT (SRP plus aPDT). The aPDT consisted of phenothiazine photosensitizer deposition followed by diode laser irradiation. Ten rats from each subgroup were euthanized at 7, 15, and 30 days after treatment. Alveolar bone loss (ABL) in the furcation region was evaluated using histological, histometric, and immunohistochemical analyses. The rats that were treated with nicotine showed more ABL compared to those treated with vehicle. In both the Veh and Nic groups, SRP plus aPDT treatment resulted in reduced ABL, smaller numbers of both TRAP- and RANKL-positive cells, and higher numbers of PCNA-positive cells compared to SRP treatment alone. aPDT was an effective adjunctive therapy for the treatment of periodontitis in female rats regardless of whether they received nicotine.

Avaliação de diferentes protocolos de aplicação da terapia fotodinâmica antimicrobiana (aPDT) no tratamento da periodontite induzida em ratos imunossuprimidos com droga quimioterápica: estudo histomorfométrico, imunoistoquímico, imunológico e microbiológico / Evaluation of different protocols of antimicrobial photodynamic therapy (aPDT) in the treatment of the induced periodontitis in rats treated with chemotherapy: a histomorphometric, immunohistochemical, immunologic and microbiological study

Objetivo: Este estudo avaliou a influência de múltiplas sessões da Terapia com Laser em Baixa Intensidade (LLLT) coadjuvante a raspagem e alisamento radicular (RAR), e da terapia fotodinâmica antimicrobiana (aPDT) associada ou não ao tratamento mecânico de RAR, no tratamento da periodontite experimental (PE) em ratos submetidos à quimioterapia com 5-Fluorouracil. Materiais e Métodos: Duzentos e dezesseis ratos foram submetidos à indução da PE por meio de ligadura no primeiro molar inferior direito e esquerdo. Após 7 dias a ligadura foi removida e os animais separados aleatoriamente em 9 grupos: PE (n=24) - sem tratamento; 5FU-PE (n=24) - tratados sistemicamente com 5FU (60mg/kg e 40mg/kg); 5FU-PE-RAR (n=24) - tratados sistemicamente com 5-FU e com RAR; 5FU-PE-RAR-1LLLT (n=24) - tratados sistemicamente com 5-FU, com RAR seguida da LLLT (sessão única) (660 nm; 0,035 W; 4,2 J, 120 segundos; 1,23 W/cm2); 5FU-PE-RAR-4LLLT (n=24) - tratados sistemicamente com 5-FU, com RAR seguida da LLLT (0, 24, 48 e 72 horas); 5FU-PE-RAR-1aPDT (n=24) - tratados sistemicamente com 5-FU, com RAR e 1 episódio de aPDT (LLLT + azul de metileno); 5FU-PE-RAR-4aPDT (n=24) - tratados sistemicamente com 5-FU, com RAR e aPDT (0, 24, 48, 72 horas); 5FU-PE-1aPDT (n=24) - tratados sistemicamente com 5-FU seguida da aPDT; 5FU-PE-4aPDT (n=24) - tratados sistemicamente com 5-FU, seguida da aPDT (0, 24, 48, 72 horas). Oito animais de cada grupo foram eutanasiados aos 7, 15 e 30 dias após tratamento local. A área de perda óssea (PO) na região de furca foi analisada histometricamente, histologicamente e análise dos padrões de imunomarcação para TRAP, PCNA RANKL, OPG e CASP-3-AT foram realizadas. A quantificação da citocina PGE2 foi avaliada pelo ELISA e TNF-α e IL-6 foram avaliadas pelos Kits de ensaio Multiplex. A prevalência de periodontopatógenos, Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella nigrescens (Pn), Prevotella intermedia (Pi) e Fusobacterium...

Objective: This study evaluated the influence of multiple sessions of Low Level Laser Therapy (LLLT), adjuvant to the scaling and root planing (SRP), and antimicrobial photodynamic therapy (aPDT), with or without the mechanical treatment of SRP, in the treatment of experimental periodontitis (EP) in rats treated with chemotherapy 5- fluorouracil (5-FU). Materials and methods: Two hundred and sixteen animals were subjected to induction of EP by ligature in mandibular first molar right and left. 7 days after the ligature was removed, the animals were randomly divided into 9 groups: EP (n=24) - no treatment; 5FU-EP (n=24) - systemically treated with 5-FU (60mg/kg and 40mg/kg); 5FU-EP-SRP (n=24) - systemically treated with 5-FU, with SRP; 5FU-EP-SRP-1LLLT (n= 24) - systemically treated with 5-FU, with SRP, followed by LLLT (single session) (660 nm, 0.035 W; 4.2 J, 120 seconds; 1.23 W/cm2); 5FU-EP-SRP-4LLLT (n= 24) - systemically treated with 5-FU, with SRP, followed by LLLT (0, 24, 48 and 72 hours); 5FU-EP-SRP-1aPDT (n=24) - systemically treated with 5-FU, with SRP, followed by one application of antimicrobial photodynamic therapy (aPDT) (LLLT + methylene blue); 5FU-EP-SRP-4aPDT (n=24) - systemically treated with 5-FU, with SRP followed by aPDT (0, 24, 48, 72 hours); 5FU-EP-1aPDT (n=24) - systemically treated with 5-FU followed by aPDT; 5FU-EP-4aPDT (n=24) - treated systemically with 5-FU, followed by treatment with aPDT (0, 24, 48, 72 hours). Eight animals in each group were euthanized at 7, 15 and 30 days after local treatment. The area of bone loss (BL) in the furcation region was analyzed histometrically, histologically and analysis of immunostaining patterns for RANKL, OPG, TRAP, PCNA and CASP-3-AT were performed. Quantity of cytokine was measured by ELISA for PGE2 and TNF-α and IL-6 were evaluated by kits multiplex assays. The prevalence of periodontopathogens Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella nigrescens...

Avaliação de diferentes protocolos de aplicação da terapia fotodinâmica antimicrobiana (aPDT) no tratamento da periodontite induzida em ratos imunossuprimidos com droga quimioterápica: estudo histomorfométrico, imunoistoquímico, imunológico e microbiológico / Evaluation of different protocols of antimicrobial photodynamic therapy (aPDT) in the treatment of the induced periodontitis in rats treated with chemotherapy: a histomorphometric, immunohistochemical, immunologic and microbiological study

Objetivo: Este estudo avaliou a influência de múltiplas sessões da Terapia com Laser em Baixa Intensidade (LLLT) coadjuvante a raspagem e alisamento radicular (RAR), e da terapia fotodinâmica antimicrobiana (aPDT) associada ou não ao tratamento mecânico de RAR, no tratamento da periodontite experimental (PE) em ratos submetidos à quimioterapia com 5-Fluorouracil. Materiais e Métodos: Duzentos e dezesseis ratos foram submetidos à indução da PE por meio de ligadura no primeiro molar inferior direito e esquerdo. Após 7 dias a ligadura foi removida e os animais separados aleatoriamente em 9 grupos: PE (n=24) - sem tratamento; 5FU-PE (n=24) - tratados sistemicamente com 5FU (60mg/kg e 40mg/kg); 5FU-PE-RAR (n=24) - tratados sistemicamente com 5-FU e com RAR; 5FU-PE-RAR-1LLLT (n=24) - tratados sistemicamente com 5-FU, com RAR seguida da LLLT (sessão única) (660 nm; 0,035 W; 4,2 J, 120 segundos; 1,23 W/cm2); 5FU-PE-RAR-4LLLT (n=24) - tratados sistemicamente com 5-FU, com RAR seguida da LLLT (0, 24, 48 e 72 horas); 5FU-PE-RAR-1aPDT (n=24) - tratados sistemicamente com 5-FU, com RAR e 1 episódio de aPDT (LLLT + azul de metileno); 5FU-PE-RAR-4aPDT (n=24) - tratados sistemicamente com 5-FU, com RAR e aPDT (0, 24, 48, 72 horas); 5FU-PE-1aPDT (n=24) - tratados sistemicamente com 5-FU seguida da aPDT; 5FU-PE-4aPDT (n=24) - tratados sistemicamente com 5-FU, seguida da aPDT (0, 24, 48, 72 horas). Oito animais de cada grupo foram eutanasiados aos 7, 15 e 30 dias após tratamento local. A área de perda óssea (PO) na região de furca foi analisada histometricamente, histologicamente e análise dos padrões de imunomarcação para TRAP, PCNA RANKL, OPG e CASP-3-AT foram realizadas. A quantificação da citocina PGE2 foi avaliada pelo ELISA e TNF-α e IL-6 foram avaliadas pelos Kits de ensaio Multiplex. A prevalência de periodontopatógenos, Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella nigrescens (Pn), Prevotella intermedia (Pi) e Fusobacterium...

Objective: This study evaluated the influence of multiple sessions of Low Level Laser Therapy (LLLT), adjuvant to the scaling and root planing (SRP), and antimicrobial photodynamic therapy (aPDT), with or without the mechanical treatment of SRP, in the treatment of experimental periodontitis (EP) in rats treated with chemotherapy 5- fluorouracil (5-FU). Materials and methods: Two hundred and sixteen animals were subjected to induction of EP by ligature in mandibular first molar right and left. 7 days after the ligature was removed, the animals were randomly divided into 9 groups: EP (n=24) - no treatment; 5FU-EP (n=24) - systemically treated with 5-FU (60mg/kg and 40mg/kg); 5FU-EP-SRP (n=24) - systemically treated with 5-FU, with SRP; 5FU-EP-SRP-1LLLT (n= 24) - systemically treated with 5-FU, with SRP, followed by LLLT (single session) (660 nm, 0.035 W; 4.2 J, 120 seconds; 1.23 W/cm2); 5FU-EP-SRP-4LLLT (n= 24) - systemically treated with 5-FU, with SRP, followed by LLLT (0, 24, 48 and 72 hours); 5FU-EP-SRP-1aPDT (n=24) - systemically treated with 5-FU, with SRP, followed by one application of antimicrobial photodynamic therapy (aPDT) (LLLT + methylene blue); 5FU-EP-SRP-4aPDT (n=24) - systemically treated with 5-FU, with SRP followed by aPDT (0, 24, 48, 72 hours); 5FU-EP-1aPDT (n=24) - systemically treated with 5-FU followed by aPDT; 5FU-EP-4aPDT (n=24) - treated systemically with 5-FU, followed by treatment with aPDT (0, 24, 48, 72 hours). Eight animals in each group were euthanized at 7, 15 and 30 days after local treatment. The area of bone loss (BL) in the furcation region was analyzed histometrically, histologically and analysis of immunostaining patterns for RANKL, OPG, TRAP, PCNA and CASP-3-AT were performed. Quantity of cytokine was measured by ELISA for PGE2 and TNF-α and IL-6 were evaluated by kits multiplex assays. The prevalence of periodontopathogens Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella nigrescens...

Treatment of experimental periodontitis in rats using repeated adjunctive antimicrobial photodynamic therapy.

The aim of this study was to histologically and histometrically evaluate the influence of repeated adjunctive antimicrobial photodynamic therapy (aPDT) on bone loss (BL) in furcation areas in rats. Periodontitis was induced by placing a ligature around the mandibular molar in 75 rats. The animals were divided into five groups: the SS group was treated with saline solution (SS); the SRP group received scaling and root planing (SRP); the aPDT1 group received SRP as well as toluidine blue (TBO) and low-level laser therapy (LLLT; InGaAlP, 660 nm; 4.94 J/cm(2)/point) postoperatively at 0 h; the aPDT2 group received SRP as well as TBO and LLLT postoperatively at 0, 24, 28, and 72 h; and the aPDT3 group received SRP, TBO, and LLLT postoperatively at 0, 48, 96, and 144 h. The area of BL in the furcation region of the molar was histometrically analyzed. Data were analyzed statistically (P < 0.05). Animals treated with a single episode of aPDT showed less BL at days 7 and 30 than those who received only SRP treatment. No significant differences were found among the aPDT groups (P > 0.05). Repeated aPDT did not improve BL reduction when compared to a single episode of aPDT.

Influence of low-level laser therapy on wound healing in nicotine-treated animals.

Low-level laser therapy (LLLT) has been shown to have several biological effects that favor the healing process, and nicotine has been shown to delay the healing process. In this study we investigated the healing of open wounds created on the back of rats treated with nicotine with or without LLLT. Of 115 animals, 59 received subcutaneous injections of saline solution, and the others received subcutaneous injections of nicotine (3 mg/kg body weight), twice a day throughout the study period. After 30 days, skin wounds were created on the back of the animals. The animals receiving saline injections were divided into two groups: group 1 (G1, n = 29), in which the wounds were left untreated, and group 2 (G2, n = 30), in which the wounds were treated with LLLT (GaAlAs, 660 nm, 30 mW, 5.57 J/cm(2) per point, 0.39 J, 13 s per point, 0.42 W/cm(2)). The animals receiving nicotine injections were also divided into two groups: group 3 (G3, n = 29), in which the wounds were left untreated, and group 4 (G4, n = 27), in which the wounds were treated with LLLT. The animals were killed 3, 7 or 14 days after surgery. Wound healing was evaluated histologically both qualitatively and semiquantitatively. Wounds of G2 showed a delay in epithelial migration and connective tissue organization compared to those of G1. Wounds of G2 showed faster healing than those of G1; similarly, wounds of G4 showed more advanced healing than those of G3. LLLT acted as a biostimulatory coadjuvant agent balancing the undesirable effects of nicotine on wound tissue healing.

Estudo histomorfométrico e imunoistoquímico dos efeitos da terapia fotodinâmica antimicrobiana no tratamento da doença periodontal induzida em ratos / Histomorphometricall and immunohistochemical study of the effect of the antimicrobial photodynamic therapy in the treatment of the induced periodontal disease in rats

Este estudo avaliou histomorfometricamente e imunoistoquimicamente os efeitos da terapia fotodinâmica antimicrobiana (aPDT), usando dois fotossensibilizadores com diferentes concentrações, como coadjuvante no tratamento da periodontite induzida em ratos. A doença periodontal (DP) foi induzida por adaptação de uma ligadura ao redor do primeiro molar inferior esquerdo em 162 ratos. Os animais foram randomicamente divididos em 9 grupos: G1 - raspagem e alisamento radicular (RAR) e irrigação com soro fisiológico; G2 - RAR e irrigação com azul de metileno (MB) (100 μg / ml); G3 - RAR e irrigação com MB (10 mg / ml); G4 - RAR e irrigação com azul de toluidina- O (TBO) (100 μg / ml); G5 - RAR e irrigação com TBO (10 mg / ml); G6 – RAR, irrigação com MB (100 μg / ml) e Laser (InGaAlP; 660nm; 4,94J/cm2/ponto; 24 segundos); G7 – RAR, irrigação com MB (10 mg / ml) e Laser; G8 – RAR, irrigação com azul de TBO (100 μg / ml) e Laser; G9 – RAR, irrigação com TBO (10 mg/ml) e Laser. A área de perda óssea (PO) na região de furca (RF) foi analisada histomorfometricamente. A quantidade de osteoclastos e os reguladores locais da atividade osteoclástica foram avaliados qualitativamente na RF via detecção imunoistoquímica de TRAP e RANKL-OPG, respectivamente. Os dados da PO foram analisados estatisticamente (P<0,05). Os animais do G1 apresentaram maior PO (2,17±0,54) comparado ao G6 (0,55±0,14), G7 (0,77±0,17) e G8 (0,73±0,17) aos 7 dias e não houve diferença estatiscamente significante entre os grupos tratados com fotossensibilizadores ou aPDT. A análise imunoistoquímica qualitativa revelou uma tendência a uma diminuição na imunorreatividade de RANKL e TRAP e um aumento na expressão de OPG nos grupos tratados com aPDT/MB. A aPDT usando o MB como uma terapia coadjuvante a RAR agiu como “downregulador” dos mecanismos moleculares que controlam a reabsorção óssea, reduzindo a PO na área de furca em ratos com periodontite induzida, enquanto que a aPDT mediada pelo TBO foi capaz de...

The aim of this study was to evaluate histomorphometric and immunohistochemical the effects of antimicrobial photodynamic therapy (aPDT), using two photosensitizers with different concentrations, as an adjunct in the treatment of induced periodontitis in rats. Periodontal disease was induced by placing a ligature around the left first mandibular molar in 162 rats. The animals were randomly divided into nine groups: G1- scaling and root planning (SRP) and irrigation with saline solution, G2- SRP and irrigation with methylene blue (MB) (100 μg/ml); G3- SRP and irrigation with MB (10 mg/ml); G4- SRP and irrigation with toluidine blue O (TBO) (100 μg/ml); G5- SRP and irrigation with TBO (10 mg/ml); G6- SRP, irrigation with MB (100 μg/ml) and Laser (InGaAlP; 660 nm; 4.94 J/cm2/point; 24 seconds); G7-SRP, irrigation with MB (10 mg/ml) and Laser; G8- SRP, irrigation with TBO (100 μg/ml) and Laser; G9- SRP, irrigation with TBO (10 mg/ml) and Laser. The area of bone loss (BL) in the furcation region (FR) was histometrically analyzed. The amount of osteoclasts and the local regulator of osteoclastic activity were evaluated qualitatively in the FR via immunohistochemical detection of TRAP and RANKL-OPG, respectively. Data were analyzed statistically (P<0.05). The animals of G1 presented more BL (2.17±0.54) compared to animals of G6 (0.55±0.14), G7 (0.77±0.17) and G8 (0.73±0.17) at 7 days. There was no statistically significant difference between the groups treated with photosensitizers or aPDT. The qualitative immunohistochemical analysis revealed that there was a tendency to decrease immunostaining of RANKL and TRAP, and a tendency to increase expression of OPG in the groups treated with aPDT/MB. The aPDT using the MB, as an adjunctive therapy to SRP was effetive to act as a downregulator in local molecular mechanisms that control bone resorption, reducing bone loss (BL) in the furcation area in rats with induced periodontitis, while the aPDT mediated by TBO was able...

Efeito da aPDT na osseointegração de implantes em alvéolos contaminados / Effect of aPDT in the osseointegration of implants in contaminated dental sockets

Objetivo: Avaliar por meio de análises histométrica e imuno-histoquímica os efeitos da terapia fotodinâmica antimicrobiana (aPDT) no tratamento alveolar prévio à colocação de implantes, em alvéolos de dentes de ratos portadores ou não de doença periodontal induzida. Material e método: Trinta e dois ratos foram utilizados no estudo. A doença periodontal foi induzida nos primeiros molares inferiores esquerdos. Decorridos sete dias, foi realizada a remoção da ligadura e a exodontia dos primeiros molares inferiores direitos e esquerdos. A seguir, os animais foram divididos em dois grupos de 16 animais, de acordo com os tratamentos realizados nos alvéolos dentais antes da instalação do implante imediato: DM-debridamento mecânico (DM), irrigação com 1 mL de soro fisiológico seguida de instalação do implante; aPDT-DM, irrigação com 1 mL de azul de toluidina O (TBO) e, após 1 minuto, irradiação com laser em baixa intensidade (LLLT). Oito animais de cada grupo foram eutanasiados aos 15 e 30 dias. Os espécimes foram processados laboratorialmente para análises histométrica do contato osso-implante (BIC) e imuno-histoquímica. Os dados histométricos foram estatisticamente analisados (Teste Kruskall-Wallis e Dunn p < 0,05). Resultado: Na análise dos tratamentos, os resultados demonstraram que houve maior BIC nos implantes instalados em alvéolos não contaminados tratados com aPDT (p < 0,05) e maior imunorreatividade à OPG no tecido ósseo tratado com aPDT. Conclusão: A aPDT mostrou-se efetiva no controle da perda óssea em áreas não contaminadas e aumentou a atividade metabólica e a atividade das células ósseas nos alvéolos irradiados previamente à instalação dos implantes.

Objective: The aim of this study is to evaluate by histometric and immunohistochemistry analysis the effects of antimicrobial photodynamic therapy (aPDT) in alveolar prior to placement of mini-implants in animals with or without induced periodontal disease. Material and method: Thirty-two rats were used. Periodontal disease (PD) was induced by ligature in the lower left first molar. After 7 days of PD evolution, it was performed removal of the ligature and extraction of the left lower first molars in all animals. Thus, animals were divided into 2 groups (n = 16) according to the treatments in the dental alveolus before immediate implant installation: MD (control) : mechanical debridement (MD), irrigation with 1 mL of saline solution followed by implant installation; aPDT-MD, irrigation with 1 mL of Toluidine Blue-O and low intensity laser (LLLT) and implant installation. Eight animals from each group were euthanized at 15 and 30 days after the installation of mini-implants. Specimens were processed for histologic, immunohistochemical and histometric analysis. The histometric data were processed for statistical analysis (Kruskall-Wallis and Dunn test; p < 0.05). Result: In treatment analysis, results indicated thatthere was a greater BIC in implants installed in uncontaminated alveolus treated with a PDT ( p < 0.05) and greater imuno-reactivity to OPG in bone issue treated with aPDT. Conclusion: The aPDT proved to be effective in bone loss control in no contaminated area and it has increased the bone loss and metabolic activity in alveolus irradiated prior to implant installation.