Comparison of different bone substitutes in the repair of rat calvaria critical size defects: questioning the need for alveolar ridge presentation.

OBJECTIVE: This study aimed to evaluate the effectiveness of biomaterials in bone healing of critical bone defects created by piezoelectric surgery in rat calvaria. METHOD AND MATERIALS: Histomorphologic analysis was performed to assess bone regeneration and tissue response. Fifty animals were randomized into five groups with one of the following treatments: Control group (n = 10), spontaneous blood clot formation with no bone fill; BO group (Bio-Oss, Geistlich Pharma; n = 10), defects were filled with bovine medullary bone substitute; BF group (Bonefill, Bionnovation; n = 10), defects were filled with bovine cortical bone substitute; hydroxyapatite group (n = 10), defects were filled with hydroxyapatite; calcium sulfate group (n = 10), defects were filled with calcium sulfate. Five animals from each group were euthanized at 30 and 45 days. The histomorphometry calculated the percentage of the new bone formation in the bone defect. RESULTS: All data obtained were evaluated statistically considering P < .05 as statistically significant. The results demonstrated the potential of all biomaterials for enhancing bone regeneration. The findings showed no statistical differences between all the biomaterials at 30 and 45 days including the control group without bone grafting. CONCLUSION: In conclusion, the tested biomaterials presented an estimated capacity of osteoconduction, statistically nonsignificant between them. In addition, the selection of biomaterial should consider the specific clinical aspect, resorption rates, size of the particle, and desired bone healing responses. It is important to emphasize that in some cases, using no bone filler might provide comparable results with reduced cost and possible complications questioning the very frequent use of ridge presentation procedures.

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.

Multiple aPDT sessions on periodontitis in rats treated with chemotherapy: histomorphometrical, immunohistochemical, immunological and microbiological analyses.

BACKGROUND: The aim of this study was to evaluate the effect of multiple sessions of antimicrobial photodynamic therapy (aPDT) on the treatment of experimental periodontitis (EP) in rats treated with chemotherapy. METHODS: Chemotherapy using 5-fluorouracil (5-FU) consisted of intraperitoneal administration of 60 and 40 mg/kg of 5-FU. 120 rats were subjected to chemotherapy with 5-FU and divided into groups: PT (periodontal treatment); PT+1aPDT (PT and single aPDT session); PT+4aPDT(PT and 4 sessions of aPDT); 1aPDT (single aPDT session); 4aPDT(4 sessions of aPDT). EP was induced in the mandibular molars via ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. Proliferating cell nuclear antigen (PCNA), tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and cleaved caspase-3 (CC3) were analysed by immunohistochemistry. Prostaglandin E2 was quantified using an ELISA, tumor necrosis factor (TNF)-α and interleukin (IL)-6 were assessed using a multiplex method. The prevalence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum was assessed using PCR. The data were statistically analysed (P < 0.05). RESULTS: The PT+4aPDT group showed lower ABL than the PT or 1aPDT groups on day 7. Rats treated with aPDT showed a higher number of PCNA-positive cells with reduced immunolabeling of RANKL. Significant reductions in Prevotella nigrescens were observed in the PT+4aPDT group and in Aggregatibacter actinomycetemcomitans for the 1aPDT and 4aPDT groups. CONCLUSION: Repeated sessions of aPDT as an adjunct or alternative therapy were effective at reducing ABL, regulating bone metabolism, and reducing Prevotella nigrescens and Aggregatibacter actinomycetemcomitans.

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.

Treatment of periodontitis in smokers with multiple sessions of antimicrobial photodynamic therapy or systemic antibiotics: A randomized clinical trial.

BACKGROUND: The aim of this study was to evaluate the effects of non-surgical periodontal therapies on smokers with chronic periodontitis, involving multiple adjunctive applications of antimicrobial photodynamic therapy (aPDT), and systemic metronidazole (MTZ) with amoxicillin (AMX). METHODS: All participants were treated with scaling and root planing (SRP). Seventeen patients received 400 mg of MTZ and 500 mg of AMX three times per day for 7 days (MTZ + AMX). Additionally, 17 patients received a placebo, and 17 patients were treated with three applications of aPDT (immediately, 48 h and 96 h after SRP). Clinical and microbiological examinations were performed at baseline and at 90 and 180 days post-therapy. Subgingival samples were analyzed using real-time polymerase chain reaction. RESULTS: After 180 days, the patients in groups MTZ + AMX and aPDT had significantly lower mean probing depths, more clinical attachment level gains and less bleeding on probing. At 180 days, in the moderate pocket there was a reduction in the levels of Porphyromonas gingivalis and Prevotella nigrescens in the MTZ + AMX group, while group aPDT showed a reduction in Prevotella nigrescens. Furthermore, at 180 days, in the deep pocket a reduction in Porphyromonas gingivalis, Prevotella intermedia and Prevotella nigrescens was observed in group MTZ + AMX, as well as a reduction in the levels of Prevotella intermedia and Prevotella nigrescens in group aPDT. CONCLUSION: In smokers with periodontitis, the MTZ + AMX and aPDT treatments significantly improved the effects of SRP.

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.

Evaluation of the progression and treatment of experimental periodontitis in rats subjected to chemotherapy with 5-fluorouracil.

AIM: This study aimed to evaluate the progression and treatment of experimental periodontitis (EP) in rats treated with 5-fluorouracil (5-FU). MATERIALS AND METHODS: One-hundred fifty rats were divided into groups: C--control, EP--EP induction, EP/scaling and root planing (SRP)--EP induction and SRP, 5-FU--systemic treatment with 5-FU, 5-FU/EP--systemic treatment with 5-FU and EP induction, and 5-FU/EP/SRP--systemic treatment with 5-FU, EP induction and SRP. Systemic treatment consisted of the administration of 80 and 40 mg/kg of 5-FU. The animals were euthanised at 7, 15 and 30 days. Histological and immunohistochemical analyses for the detection of the receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP) were performed at the furcation region. A histometric analysis was performed to evaluate the percentage of bone in the furcation region (PBF). RESULTS: In the 5-FU/EP and 5-FU/EP/SRP groups, there was less PBF, greater breakdown of periodontal tissues and increased immunostaining for RANKL compared with the EP and EP/SRP groups. CONCLUSION: It can be concluded that 5-FU aggravates PE progression, impairs the host response to SRP mechanical therapy and does not seem to cause changes in the healthy periodontium.

Effect of antimicrobial photodynamic therapy on periodontally infected tooth sockets in rats.

The aim of the present study was to evaluate the antimicrobial effect of antimicrobial photodynamic therapy (aPDT) in alveolar treatment of areas with induced periodontitis. Thirty male Wistar rats were subjected to ligature-induced periodontal disease (PD) in the first left inferior molars, while the right side molars did not receive ligatures. After 7 days of PD evolution, ligatures were removed from the left side, and the first left and right mandibular molars were extracted. Afterwards, animals were divided into groups according to the following treatments: control (C)--no treatment; mechanical debridement (MD)--mechanical debridement and irrigation with saline solution; and aPDT--mechanical debridement, irrigation with toluidine blue O (TBO), and 1 min of laser irradiation (GaAlAs, 660 nm, 30 mW, 32 J/cm(2), 60 s). Ligatures were removed and samples of the alveolar content after extraction and after each treatment were collected for microbial processing by real-time polymerase chain reaction with specific primers for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola. Data were submitted to statistical analysis by multiple comparison tests (McNemar test; p < 0.05). T. denticola was not found in the collected samples. A. actinomycetemcomitans and P. gingivalis were found in ligature samples. Tooth socket samples without periodontitis induction presented lesser microbial charge than samples with induced periodontitis (p < 0.05). aPDT significantly reduced A. actinomycetemcomitans levels on the left side (p < 0.05). It was concluded that aPDT was an effective antimicrobial treatment for tooth sockets in areas affected by induced periodontitis.

Effectiveness of the diode laser in the treatment of ligature-induced periodontitis in rats: a histopathological, histometric, and immunohistochemical study.

The aim of this study was to evaluate the effects of the use of a high-power gallium-aluminum-arsenide diode laser (GaAlAs; 808 nm, 1 W, 20 s, 20 Hz, 10 J) alone or as adjunctive therapy to scaling and root planing in the treatment of induced periodontitis in rats. Periodontitis was induced by placing a ligature around the mandibular first molar of 60 rats. After 7 days, the ligature was removed and the animals were divided into four groups as follows: C (control), no periodontal treatment; SRP, scaling and root planing (SRP); DL, diode laser (DL) irradiation treatment; and SRP/DL, both SRP and DL irradiation treatment. Five animals from each group were euthanized at 7, 15, and 30 days posttreatment. The effectiveness of the treatments was evaluated in the furcation area using histopathological analysis, histometric analysis of alveolar bone loss (ABL), and immunohistochemical detection of tartrate-resistant acid phosphatase (TRAP), runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN). DL, alone or in combination with adjunctive therapy to SRP in the treatment of experimental periodontitis, resulted in a decreased local inflammatory response. At 7-days posttreatment, the DL and SRP/DL groups had fewer TRAP-positive cells and more RUNX2-positive cells. There was greater OCN immunolabeling in the DL group than in the C and SRP groups at 15 days. There was less ABL in the DL and SRP/DL groups at 15 and 30 days. In conclusion, DL was effective in the treatment of ligature-induced periodontitis in rats, both when used alone and when used as adjunctive therapy to SRP.

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...

Effect of LLLT on autogenous bone grafts in the repair of critical size defects in the calvaria of immunosuppressed rats.

The aim of this study was to evaluate the effects of low-level laser therapy (LLLT) on the bone repair of critical size defects (CSDs) filled with autogenous bone in the calvaria of immunosuppressed rats. A 5 mm-diameter CSD was created in the calvaria of 30 rats. The animals were divided into 5 groups (n = 6): Control (C)--the defect was filled with a blood clot; Dexamethasone (D)--dexamethasone treatment, and the defect was filled with a blood clot; Autogenous bone (AB)--dexamethasone treatment, and the defect was filled with autogenous bone; LLLT--dexamethasone treatment, and the defect received LLLT (660 nm; 35 mW; 24.7 J/cm(2)); and AB + LLLT--dexamethasone treatment, and the defect was filled with autogenous bone and received LLLT. All animals were euthanized at 30 postoperative days. Histometric and histological analyses were performed. The new bone area (NBA) was calculated as the percentage of the total area of the original defect. Data were analysed statistically (an analysis of variance and Tukey's test; P < 0.05). The AB + LLLT group showed the largest NBA of all groups (P < 0.05). The use of LLLT with AB effectively stimulated bone formation in CSDs in the calvaria of immunosuppressed rats.

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.