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.

Adjuvant effects of Saccharomyces cerevisiae in the treatment of experimental periodontitis in rats undergoing chemotherapy.

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.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%). 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). 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.

A randomised trial of the bone formation after maxillary sinus floor augmentation with bovine hydroxyapatite (Cerabone®) and Photobiomodulation: histomorphometric and immunohistochemical analysis.

Background: The use of non-autogenous biomaterial to increase bone height in the maxillary sinus has been shown to be effective, but the results are still inconclusive. Material and Methods: Eight participants were selected and included in the research. After surgical access with osteotomy on the lateral wall of both maxillary sinuses, these were filled with Cerabone®. Then, by blind randomization, they received one of the following treatments: Filling with Cerabone® (Control group); treatment with Photobiomodulation (PBM), filling with Cerabone® and treatment with low-power laser (PBM group). Biopsies were obtained 30 days after the surgery, using a 2.8 mm internal diameter trephine bur. Qualitative and quantitative histological analyzes were performed and immunohistochemical analyzes of osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) were performed with scores for each of the biological events. Results: The Cerabone® biomaterial demonstrated a high degree of biocompatibility. New bone formation was observed in both groups. In the PBM group, there was greater bone formation and newly formed tissue in an advanced state of bone maturation. The immunostaining of OCN was greater at 30 days in the PBM group than in the control. There was no significant difference in TRAP immunostaining at 30 days between the groups. Conclusions: Low-power laser-mediated by PBM promoted greater bone formation; the newly formed tissue showed a more advanced state of bone maturation in maxillary sinuses filled with Cerabone® biomaterial and treatment with PBM, within the 30-day evaluation period. Key words:Sinus floor augmentation, dental implants, bone and bones, low-level light therapy.

Single intraoperative infrared laser optimized bone repair in rat femoral osteotomies with experimentally induced osteoporosis.

This study aimed to evaluate the effect of infrared laser (IRL) on bone repair in ovariectomized rats subjected to femoral osteotomies. Of 32 rats, half underwent bilateral ovariectomy (OVX) and the other half underwent sham ovariectomy (SHAM). A period of 3 months was defined to observe the presence of osteoporosis. The rats were subjected to osteotomies in the femurs and then fixed with a miniplate and 1.5-mm system screws. Thereafter, half of the rats from both SHAM and OVX groups were not irradiated, and the other half were irradiated by IRL using the following parameters: wavelength, 808 nm; power, 100 mW; 60 s for each point; 6 J/point; and a total of 5 points of bone gap. All animals were euthanized 60 days after surgery. The femur gap was scanned using micro-computed tomography (micro-CT). The samples were then examined under a confocal laser microscope to determine the amounts of calcein and alizarin red. The slides were stained with alizarin red and Stevenel's blue for histometric analysis. In the micro-CT analysis, the OVX groups had the lowest bone volume (P < 0.05). When the laser was applied to the OVX groups, bone turnover increased (P < 0.05). New bone formation (NBF) was comparable between SHAM and OVX/IR (P > 0.05) groups; however, it was less in the OVX groups (P < 0.05). In conclusion, the results encourage the use of IRL intraoperatively as it optimizes bone repair, mainly in animals with low bone mineral density.

Adjuvant effects of Saccharomyces cerevisiae in the treatment of experimental periodontitis in rats undergoing chemotherapy

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.

Influence of the treatment with the antineoplastic agents 5-fluorouracil and cisplatin on the severity of experimental periodontitis in rats.

PURPOSE: The determination on how antineoplastic agents interfere on the progression of periodontitis is critical for improvement and even development of novel therapeutic approaches for periodontal management. This study evaluated the influence of chemotherapy with 5-fluorouracil (5-FU) or cisplatin (CIS) on healthy periodontal tissues and on the progression of experimental periodontitis (EP). METHODS: One hundred forty-four male rats were divided into six groups (n = 24). Each group was treated with physiological saline solution (PSS) 0.9%, 5-FU, or CIS. Experimental periodontitis (EP) was induced by ligature placement. Animals were euthanized at 7, 15, and 30 days after treatment. Data were statistically analyzed (p ≤ 0.05). RESULTS: The groups with EP and treated with 5-FU or CIS showed lower percentage of bone volume in the furcation region and higher percentage of alveolar bone loss, higher number of TRAP-positive cells, and lower number of PCNA-positive cells when compared group with EP and treated with PSS (p ≤ 0.05). Groups with EP and treated with 5-FU or CIS showed high immunolabelling pattern of RANKL, TNF-α, and IL-1ß, moderate of BAX, and low of HIF-1α. Histological analysis showed severe tissue breakdown in the groups with EP and treated with 5-FU or CIS. CONCLUSIONS: Chemotherapy with antineoplastic agents 5-FU and CIS increased the intensity and duration of the inflammation and compromised tissue repair by reduction in cellular and vascular turnover. The more severe periodontal breakdown was caused by 5-FU.

LASER in periodontal treatment: is it an effective treatment or science fiction?

There are several studies that evaluate the use of lasers in periodontal treatment in non-surgical or surgical therapy. However, while several studies showed clinically beneficial effects of some lasers in periodontal treatment, there are few clinical reports of additional advantages of lasers as adjunctive treatments in periodontology. The aim of this paper is to demonstrate and critically analyze the level of scientific evidence of effects of low-level lasers and high-power lasers in periodontology. A narrative review of the studies was carried out in each topic and type of laser or periodontal treatment. In nonsurgical periodontal therapy the results showed that there is an additional clinical benefit when using a diode laser (DL) associated with scaling and root planing (SRP) in patients with moderate to severe periodontitis. The Er:YAG laser seems to be the most suitable for nonsurgical periodontal therapy and promotes the same clinical effects as conventional therapy. In periodontal surgery vaporization of the gingival or mucosal tissue can be carried out with DL, CO2, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers. Photobiomodulation (PBM), mediated by low-level lasers associated with non-surgical periodontal therapy, promotes additional benefits in the short term and accelerates the bone and gingival tissue repair process and also reduces postoperative symptoms of periodontal surgery. The effect of antimicrobial Photodynamic Therapy is relevant in the initial reevaluation periods. Studies have shown controversial results of the use of lasers in periodontics, and this fact may be due to the lack of standard parameters of irradiation in each clinical application.

Is an anodizing coating associated to the photobiomodulation able to optimize bone healing in ovariectomized animal model?

This in vivo study investigated whether the bioactivity of anodizing coating, produced by plasma electrolytic oxidation (PEO), on mini-plate in femur fracture could be improved with the association of photobiomodulation (PBM) therapy. From the 20 ovariectomized Wistar female rats, 8 were used for model characterization, and the remaining 12 were divided into four groups according to the use of PBM therapy by diode laser (808 nm; power: 100 mW; energy: 6.0 J; energy density: 212 J/cm2; power density: 3.5 W/cm2) and the type of mini-plate surface (commercially pure titanium mini-plate -cpTi- and PEO-treated mini-plate) as follow: cpTi; PEO; cpTi/PBM; and PEO/PBM. After 60 days of surgery, fracture healing underwent microstructural, bone turnover, histometric, and histologic adjacent muscle analysis. Animals of groups with PEO and PBM showed greater fracture healing than cpTi control group under histometric and microstructural analysis (P < 0.05); however, bone turnover was just improved in PBM's groups (P < 0.05). there was no difference between cpTi and PEO without PBM (P > 0.05). Adjacent muscle analysis showed no metallic particles or muscle alterations in all groups. PEO and PBM are effective strategies for bone repair in fractures, however their association does not provide additional advantages.

LASER in periodontal treatment: is it an effective treatment or science fiction?

Abstract There are several studies that evaluate the use of lasers in periodontal treatment in non-surgical or surgical therapy. However, while several studies showed clinically beneficial effects of some lasers in periodontal treatment, there are few clinical reports of additional advantages of lasers as adjunctive treatments in periodontology. The aim of this paper is to demonstrate and critically analyze the level of scientific evidence of effects of low-level lasers and high-power lasers in periodontology. A narrative review of the studies was carried out in each topic and type of laser or periodontal treatment. In nonsurgical periodontal therapy the results showed that there is an additional clinical benefit when using a diode laser (DL) associated with scaling and root planing (SRP) in patients with moderate to severe periodontitis. The Er:YAG laser seems to be the most suitable for nonsurgical periodontal therapy and promotes the same clinical effects as conventional therapy. In periodontal surgery vaporization of the gingival or mucosal tissue can be carried out with DL, CO2, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers. Photobiomodulation (PBM), mediated by low-level lasers associated with non-surgical periodontal therapy, promotes additional benefits in the short term and accelerates the bone and gingival tissue repair process and also reduces postoperative symptoms of periodontal surgery. The effect of antimicrobial Photodynamic Therapy is relevant in the initial reevaluation periods. Studies have shown controversial results of the use of lasers in periodontics, and this fact may be due to the lack of standard parameters of irradiation in each clinical application.

Effect of systemic ozone therapy as a biomodulator of tissue regeneration and inflammatory response in rats / Efeito da terapia sistêmica de ozônio como um biomodulador da regeneração tecidual e da resposta inflamatória em ratos

Introduction Among the therapeutic effects of ozone therapy, improvement in cell metabolism and peripheral tissue oxygenation have been highlighted. Objective to evaluate the systemic effect of bio-oxidative therapy with ozone gas on wound healing. Material and method Tissue lesions with a circumference of 1.0 cm were induced in the skin on the back of 24 male Wistar rats. The animals were randomly divided into two groups: 1) Group C (control; n=12): with simulation of the application of ozone gas via the rectum and, 2) Group O3 (test; n=12): with application of ozone gas by means of rectal insufflation at a concentration of 50 µg/mL. The animals were euthanized at seven and 15 days, and samples were removed, fixed in formalin, and submitted to macroscopic, histological, and histometric analyses. Result The animals in the O3 group presented mixed inflammation at seven days, which translated into an absence of inflammation at 15 days. The C group exhibited acute inflammation on the 7th day, translating to chronic inflammation, which significantly increased from the 7th to the 15th day. The findings showed that the O3 group presented greater wound contraction (P<0.05) and a greater degree of neovascularization on the 7th day (P<0.05) when compared to group C. On the 15th day, both groups (O3 and C) showed complete re-epithelialization, however, the O3 group demonstrated complete muscle regeneration. Conclusion The systemic ozone therapy had a biomodulatory effect, reducing the characteristics of acute inflammation and increasing tissue repair and regeneration in rat skin.

Introdução Dentre os efeitos terapêuticos da ozonioterapia, destacam-se a melhora do metabolismo celular e da oxigenação dos tecidos periféricos. Objetivo avaliar o efeito sistêmico da terapia bio-oxidativa com gás ozônio na cicatrização de feridas. Material e método Lesões teciduais com circunferência de 1,0 cm foram induzidas na pele do dorso de 24 ratos Wistar machos. Os animais foram divididos aleatoriamente em dois grupos: 1) Grupo C (controle; n = 12): com simulação da aplicação de gás ozônio pelo reto e, 2) Grupo O3 (teste; n = 12): com aplicação de gás ozônio por meio de insuflação retal na concentração de 50 µg / mL. Os animais foram sacrificados com sete e 15 dias, e as amostras foram retiradas, fixadas em formalina e submetidas às análises macroscópica, histológica e histométrica. Resultado Os animais do grupo O3 apresentaram inflamação mista aos sete dias, que se traduziu em ausência de inflamação aos 15 dias. O grupo C apresentou inflamação aguda no 7º dia, traduzindo-se em inflamação crônica, que aumentou significativamente do 7º para o 15º dia. Os achados mostraram que o grupo O3 apresentou maior contração da ferida (P <0,05) e maior grau de neovascularização no 7º dia (P <0,05) quando comparado ao grupo C. No 15º dia, ambos os grupos (O3 e C) apresentaram completa reepitelização, entretanto, o grupo O3 demonstrou completa regeneração muscular. Conclusão A ozonioterapia sistêmica teve efeito biomodulador, reduzindo as características de inflamação aguda e aumentando a reparação e regeneração tecidual na pele de ratos.

Prevalence of Gingival Hyperplasia Induced by Anticonvulsants: A Systematic Review / Prevalência da Hiperplasia Gengival Induzida pelo uso de anticonvulsivantes: Revisão sistemática

Objective: Gingival hyperplasia (GH) is one of the side effects of anticonvulsant drugs. The aim of this study was to verify the prevalence of GH associated with the use of anticonvulsant, through a systematic review. Material and Methods: Systematic search was done at databases Pubmed and Embase between January 1984 and March of 2020 for identification of articles addressing the prevalence of GH associated with the use of anticonvulsant drugs. The methodological index for non-randomized studies (MINORS) was independently assessed for quality in the selected papers. Results: The search identified 4.471 references. Nine articles were selected and evaluated 632 participants. All of the studies included in the systematic review showed a low risk of bias. The anticonvulsants used by patients were carbamazepine, ethosuximide, phenytoin, primidone, phenobarbital, sodium valproate. The studies showed a correlation between different types of anticonvulsants and GH prevalence, with a range from 0% to 73%. Among the anticonvulsants used, phenytoin showed the greatest incidence of GH, varying between 15.61% and 73% in patients. Conclusion: In the analysis of the results obtained in the literature, it is possible to notice that the great majority of studies presented incidence of GH associated with anticonvulsant use. However, further studies are necessary to understand the anticonvulsant action mechanism inducing GH, as well as the prevention forms, given that GH is a significant side effect. (AU)

Objetivo: Hiperplasia gengival (HG) é um dos efeitos colaterais das drogas anticonvulsivantes. O objetivo deste estudo foi verificar a prevalência de HG associada ao uso de anticonvulsivantes, por meio de uma revisão sistemática. Material e Métodos: A busca sistemática foi realizada nas bases de dados Pubmed e Embase entre janeiro de 1984 e março de 2020 para identificação de artigos que abordassem a prevalência de HG associada ao uso de drogas anticonvulsivantes. Foi avaliado independentemente, o risco de viés através do "Methodological index for non-randomized studies" (MINORS), para análise da qualidade dos trabalhos selecionados. Resultados: A pesquisa identificou 4.471 referências. Nove artigos foram selecionados e avaliaram 632 participantes. Todos os estudos incluídos na revisão sistemática mostraram baixo risco de viés. Os anticonvulsivantes utilizados pelos pacientes foram carbamazepina, etossuximida, fenitoína, primidona, fenobarbital e valproato de sódio. Os estudos mostraram correlação entre os diferentes tipos de anticonvulsivantes e a prevalência de HG, com variação entre 0% a 73%. Entre os anticonvulsivantes utilizados, a fenitoína apresentou a maior incidência de HG, variando entre 15,61% e 73% em pacientes. Conclusão: Na análise dos resultados obtidos na literatura, é possível notar que a grande maioria dos estudos apresentou incidência de HG associada ao uso de anticonvulsivantes. No entanto, estudos adicionais são necessários para compreender o mecanismo de ação do anticonvulsivante para a indução da HG, bem como as formas de prevenção, dado que a HG é um efeito colateral significativo (AU)

Lactobacillus reuteri associated with scaling and root planing in the treatment of periodontitis in rats submitted to chemotherapy.

OBJECTIVE: The aim of this study was to evaluate the effects of Lactobacillus reuteri applied locally or systemically with scaling and root planing (SRP) to the treatment of experimental periodontitis (EP) in rats treated with 5-fluorouracil. METHODS: A cotton ligature was installed on the molars of rats. The animals (n = 54) underwent chemotherapy and were divided into groups: SRP (n = 18), scaling and root planing only; LP (n = 18), SRP and 4 sessions of local probiotic (PRO); SP, SRP and 4 sessions of systemic PRO. The molar furcation area was submitted to histopathological, histometric of alveolar bone loss (ABL) and immunolabeling analysis after euthanasia at 7, 15 and 30 days. The data were submitted to statistical analysis (α = 5%). RESULTS: At 15 days ABL was higher in LP compared to SP. At 30 days, ABL was higher in LP compared to SRP and SP. Higher immunolabeling of TGF-ß1 was observed in LP and SP at 7 days compared to SRP (p < 0.05). Lower immunolabeling of OCN and higher immunolabeling of RANKL were observed at all periods in SRP compared to SP (p < 0.05). At 30 days, SRP showed lower immunolabeling of OPG compared to SP and LP (p < 0.05). In SP, lower immunolabeling was observed at 15 days compared at 30 days (p < 0.05). CONCLUSION: The ABL was similar among the groups treated with SRP associated or not to probiotic therapeutic, although the systemic use of Lactobacillus reuteri considerably reduced inflammation and favored periodontal tissues repair.

The Effectiveness of the Low-Level Laser, Antibiotic and Surgical Therapy in the Treatment of Medication-Related Osteonecrosis of the Jaws: A Case Report.

Introduction: Bisphosphonates consist of a range of drugs used in the treatment of osteopathy or some osteotropic malignancies. Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse consequence of their use. Conventional treatment is not always effective, so it is necessary to resort to the use of adjuvant therapies. This study aimed to evaluate the effectiveness of the association of surgery, antibiotic therapy and low-level laser (LLL) therapy as a treatment strategy for MRONJ through the presentation of a clinical case. Case Presentation: A 49-year-old female patient presented for the diagnosis and treatment of bone lesions in the maxillae. The patient reported that she had used zoledronate for 1 year. Five years later there were 2 painless bone lesions on both sides of the maxilla, following the extraction of the first upper molars. Clinical, tomographic and histopathologic examination established the diagnosis of MRONJ. The treatment consisted of the curettage of the necrotic bone, antibiotic and thirteen LLL therapy sessions. Integral mucosal healing was observed after a two-month follow-up and no symptoms were detected. The patient was evaluated at 6 and 12 postoperative months without complications. Conclusion: The combination of surgery, antibiotic therapy, and LLL therapy has shown to be effective in the treatment of MRONJ.

Antineoplastic agents exacerbate periodontal inflammation and aggravate experimental periodontitis.

AIM: This study evaluated the effects of 5-fluorouracil (5-FU) and cisplatin (CIS) in healthy periodontal tissues and in the early stages of experimental periodontitis (EP) in rats. METHODS: One hundred and eighty male rats were divided into three groups, which were submitted to the following systemic treatments: physiological saline solution (PSS); CIS and 5FU. Each group was subdivided into two subgroups: without (NEP) and with (EP) induction of EP. Animals were euthanized at 3, 5 and 7 days post-treatment. Histological, histometric (percentage of bone in the furcation [PBF]) and immunohistochemical (for tumour necrosis factor-α, interleukin-1ß and receptor activator of nuclear factor-κB ligand) analyses were performed. Data were statistically analysed. RESULTS: CIS-NEP and 5FU-NEP showed more inflammation than PSS-NEP at 3, 5 and 7 days. CIS-EP and 5FU-EP showed more inflammation and lower PBF than PSS-EP at all periods of evaluation. 5FU-EP showed lower PBF than CIS-EP at 5 and 7 days. CONCLUSION: 5-FU and CIS exacerbated periodontal inflammation and aggravated the progression of EP in its early stages.

Antimicrobial photodynamic therapy improves the alveolar repair process and prevents the occurrence of osteonecrosis of the jaws after tooth extraction in senile rats treated with zoledronate.

This study evaluated the effects of antimicrobial photodynamic therapy (aPDT) in the alveolar repair of rats with major risk factors for bisphosphonate-related osteonecrosis of the jaws (BRONJ). Senile rats received 0.45 ml of vehicle (VEH and VEH/aPDT) or 0.45 ml of zoledronate (ZOL and ZOL/aPDT) every three days for seven weeks. After three weeks of treatment, the first lower left molar was extracted. VEH/aPDT and ZOL/aPDT were submitted to aPDT on the extraction site at 0, 2 and 4 days postoperatively. Euthanasia was performed 28 days postoperatively and the extraction site was evaluated by clinical, histological, histometric, histochemical and immunohistochemical analysis. ZOL showed tissue repair impairment; lower percentage of newly formed bone tissue (NFBT); higher percentage of non-vital bone tissue (NVBT); fewer mature collagen fibers and increased immunolabeling for tumor necrosis factor (TNFα), interleukin (IL)-1ß and IL-6. ZOL/aPDT showed clinical and histological characteristics of the extraction site, percentage of NFBT and percentage of mature collagen fiber similar to VEH. Percentage of NVBT and immunolabeling for inflammatory cytokines in ZOL/aPDT was lower than in ZOL. Immunolabeling for tartarato-resistant acid phosphatase (TRAP) was lower in ZOL and ZOL/aPDT. aPDT in the dental extraction site improves tissue repair process and prevents the occurrence of BRONJ-like lesions after tooth extraction.

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.

aPDT for periodontitis treatment in ovariectomized rats under systemic nicotine.

BACKGROUND: This study evaluated the antimicrobial photodynamic therapy (aPDT) as an adjunctive therapy to scaling and root planning (SRP) for the treatment of experimental periodontitis (EP) in ovariectomized rats under systemic nicotine. METHODS: Female ovariectomized rats (n = 180) were divided into two groups: vehicle administration (Veh) and nicotine administration (Nic). Mini-pumps containing either vehicle or nicotine were inserted in the rats 30 days before the induction of EP, which was induced by placing a ligature around the left mandibular first molar. The rats were randomly divided into three treatment subgroups: SRP, SRP plus low-level laser therapy (LLLT), and SRP plus aPDT. aPDT consisted of the application of a phenothiazine photosensitizer followed by LLLT. Ten animals from each group were euthanized at days 7, 15, and 30 after periodontal treatment. The furcation region was evaluated using histological, histometric analyses and immunolabelling for PCNA, TRAP, RANKL, and OPG. RESULTS: Nicotine administration resulted in greater bone loss (BL). aPDT resulted in lower BL compared to SRP. aPDT showed higher quantities of PCNA-positive cells compared to SRP, regardless of the nicotine status. aPDT resulted in less recruitment of osteoclasts and lower RANKL immunolabelling compared to LLLT and SRP. CONCLUSION: aPDT was effective in animals treated with nicotine.

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.

Cisplatin chemotherapy impairs the peri-implant bone repair around titanium implants: An in vivo study in rats.

AIM: The purpose of this study in animals was to evaluate the peri-implant bone repair against systemic administration of the antineoplastic agent. MATERIAL AND METHODS: We used 84 male rats (Rattus norvegicus, albinus, Wistar), divided into two groups: cisplatin (CIS) and saline solution (SS). The titanium implants were inserted into the right tibia at day 0 in all animals from both groups. Group SS received SS intraperitoneally at 15 and 17 days postoperatively. Group CIS received 5 and 2.5 mg/kg of CIS intraperitoneally at 15 and 17 days postoperatively, respectively. Euthanasia was performed at 22, 30 and 60 days postoperatively. Twenty-four undecalcified specimens were prepared for histometric analysis of bone/implant contact (BIC). Sixty specimens were selected to bone area (BA) measurement, histological analysis and immunohistochemical analysis of RUNX-2, osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP). BIC and BA were considered to be the primary outcome parameters. RESULTS: Group CIS showed lower BIC (11.87 ± 0.97 mm; 19.19 ± 0.8 mm; 17.69 ± 1.05 mm; p ≤ .05) and BA (3.68 ± 1.29 mm2 ; 3.05 ± 0.88 mm2 ; 3.23 ± 0.67 mm2 ; p ≤ .05), as well as decreased number of RUNX-2 (102.8 ± 27.35 cells/mm2 ; 100.04 ± 8.61 cells/mm2 ; 118.82 ± 21.38 cells/mm2 ; p ≤ .05)- and OCN-positive cells (120 ± 24.5 cells/mm2 ; 102 ± 27.73 cells/mm2 ; 100 ± 14.23 cells/mm2 ; p ≤ .05) at 22, 30 and 60 days, respectively. The animals in group CIS also showed increased number of TRAP-positive cells (86.8 ± 6.37 cells/mm2 ; 71.5 ± 4.72 cells/mm2 ; 92.8 ± 9.52 cells/mm2 ; p ≤ .05) and a persistent and exacerbated inflammatory response in all experimental periods. CONCLUSION: Within the limits of this study, it was concluded that the chemotherapeutic CIS negatively affects the bone repair at peri-implant areas, jeopardizing the osseointegration of titanium implants.

aPDT como coadjuvante no tratamento da periodontite agressiva localizada / aPDT as an adjuvant in the treatment of localized aggressive periodontitis ­ report of two cases

A terapia fotodinâmica antimicrobiana (aPDT) tem demonstrado, em alguns estudos clínicos, ser efetiva como terapia coadjuvante à raspagem e alisamento radicular (RAR) na periodontite agressiva. Além dos efeitos antimicrobianos da aPDT, a irradiação com laser de baixa intensidade pode modular a resposta dos tecidos periodontais. O objetivo deste trabalho foi relatar o uso da aPDT como coadjuvante à RAR no tratamento de periodontite agressiva localizada. Duas pacientes do sexo feminino, com 31 e 23 anos de idade, sem envolvimento sistêmico, procuraram atendimento odontológico relatando desconforto ao mastigar. Clinicamente, observou-se presença de tecido gengival edemaciado e sinais de inflamação discretos. A média de sítios com profundidade a sondagem (PS) maior do que 4 mm foi de 15,43% e 4,93%, respectivamente. As duas pacientes foram submetidas à sessão única de RAR usando ultrassom e curetas manuais, seguida da aplicação da aPDT em todas as bolsas com PS  4 mm. O protocolo da aPDT seguiu os seguintes parâmetros: azul de metileno (10 mg/ml) seguido de irradiação com laser de baixa potência após um minuto da aplicação (AsGaAl, 660 nm, 100 mW, 48 segundos, 157 J/cm2). Na reavaliação, foi verificada diminuição média da PS de 1,16 mm (caso 1) e 1,13 mm (caso 2) nas bolsas tratadas com aPDT, com redução do número de sítios com sangramento em ambos os casos. De acordo com os resultados clínicos observados, sugere-se que a aPDT apresenta-se como uma terapia coadjuvante promissora no tratamento da periodontite agressiva localizada.

Antimicrobial photodynamic therapy (aPDT) has been shown, in some clinical studies, to be effective as an adjunct therapy to scaling and root planing (SRP) in aggressive periodontitis. In addition to the antimicrobial effects of aPDT, low intensity laser irradiation can modulate the response of periodontal tissues. The objective of this work is to report the use of aPDT as an adjuvant to SRP in the treatment of localized aggressive periodontitis. Two female patients, 31 and 23 years of age, without systemic involvement, sought dental care, reporting discomfort when chewing. Clinically, the presence of gingival swollen tissue and discrete signs of infl ammation were observed. The mean number of sites with probing depth (PD) greater than 4 mm was 15.43% and 4.93%, respectively. The two patients received a single SRP session using ultrasound and manual curettes, followed by the application of aPDT in all pockets with PS  4 mm. The aPDT protocol followed the parameters: methylene blue (10 mg/ml) followed by low-power laser irradiation after 1 minute of application (AsGaAl, 660 nm, 100 mW, 48 seconds, 157 J/cm2). The mean PD decrease of 1.16 mm (case 1) and 1.13 mm (case 2) in the pockets treated with aPDT were observed, with a reduction in the number of sites with bleeding in both cases. According to the clinical results observed, it is suggested that aPDT is a promising adjuvant therapy for the treatment of localized aggressive periodontitis.