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This study aimed to evaluate the potential of strontium ranelate (SR) in medication-related jaw osteonecrosis (MRONJ) after tooth extraction in ovariectomized rats. Thirty ovariectomized rats were divided into three groups (n = 10): bisphophonate (BP) group (zoledronic acid; 0.4 mg/kg/week), SR group (625 mg/kg/day), and control group (saline solution). The lower first molars were extracted after 60 days of drug therapy. Drug administration was continued for another 30 days after tooth extraction. The mandibles were subjected to clinical, histological, radiographic, and microtomographic evaluations. Only the BP group showed clinical changes, characterized by the presence of 70% (n = 7) and 20% (n = 2) of ulcers and extraoral fistulas. Radiographic evaluation demonstrated bone sequestration only in the BP group (n = 7, 70%). Microtomographic analysis revealed increased bone porosity after ovariectomy, particularly in the the control group (p < 0.05). The BP group showed a higher bone surface density, bone volume, and trabecular number than SR and control groups, but with less trabecular separation (p < 0.05). All the animals in the BP group demonstrated histological osteonecrosis. There was no evidence of osteonecrosis in the control and SR groups, which was characterized by the absence of empty osteocyte gaps and associated with the gradual healing of the extraction area. Also, an increased number of blood vessels and a reduced number of osteoclasts were observed in the SR group (p < 0.05). Therefore, SR treatment increased angiogenesis and osteoclastogenesis in the healing socket and was not associated with MRONJ development after tooth extraction in ovariectomized rats.

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Abstract This study aimed to evaluate the potential of strontium ranelate (SR) in medication-related jaw osteonecrosis (MRONJ) after tooth extraction in ovariectomized rats. Thirty ovariectomized rats were divided into three groups (n = 10): bisphophonate (BP) group (zoledronic acid; 0.4 mg/kg/week), SR group (625 mg/kg/day), and control group (saline solution). The lower first molars were extracted after 60 days of drug therapy. Drug administration was continued for another 30 days after tooth extraction. The mandibles were subjected to clinical, histological, radiographic, and microtomographic evaluations. Only the BP group showed clinical changes, characterized by the presence of 70% (n = 7) and 20% (n = 2) of ulcers and extraoral fistulas. Radiographic evaluation demonstrated bone sequestration only in the BP group (n = 7, 70%). Microtomographic analysis revealed increased bone porosity after ovariectomy, particularly in the the control group (p < 0.05). The BP group showed a higher bone surface density, bone volume, and trabecular number than SR and control groups, but with less trabecular separation (p < 0.05). All the animals in the BP group demonstrated histological osteonecrosis. There was no evidence of osteonecrosis in the control and SR groups, which was characterized by the absence of empty osteocyte gaps and associated with the gradual healing of the extraction area. Also, an increased number of blood vessels and a reduced number of osteoclasts were observed in the SR group (p < 0.05). Therefore, SR treatment increased angiogenesis and osteoclastogenesis in the healing socket and was not associated with MRONJ development after tooth extraction in ovariectomized rats.

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OBJECTIVES: Neutrophil extracellular traps (NETs) play a role in the pathogenesis of periodontitis and rheumatoid arthritis (RA). However, it remains poorly understood whether NETs participate in the cross-talk between periodontitis and RA. Herein, we investigated the production of NETs in individuals with periodontitis and RA and its association with clinical parameters. The impact of periodontal therapy on RA and NET release was also assessed. METHODS: The concentration of NETs and cytokines was determined in the saliva and plasma of individuals with early RA (n = 24), established RA (n = 64) and individuals without RA (n = 76). The influence of periodontitis on the production of NETs and cytokines was also evaluated. RESULTS: Individuals with early RA had a higher concentration of NETs in saliva and plasma than individuals with established RA or without RA. Periodontitis resulted in an increase in the concentration of NETs of groups of individuals without RA and with early RA. The proportion of individuals with high concentrations of IL-6, IL-10 and GM-CSF was higher among individuals with periodontitis than among individuals without periodontitis. The concentrations of TNF-α, IL-6, IL-17/IL-25 and IL-28A were particularly high in individuals with early RA. Worse periodontal clinical parameters, RA onset and RA activity were significantly associated with circulating NETs. Periodontal therapy was associated with a reduction in the concentration of NETs and inflammatory cytokines and amelioration in periodontitis and RA. CONCLUSION: This study reveals that NETs are a possible link between periodontitis and RA, with periodontal therapy resulting in a dramatic switch in circulating NET levels.

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PURPOSE: To evaluate the use of demineralized bone matrix of caprine origin in experimental bone defects of the tibia in New Zealand rabbits. METHODS: Fragments of the tibia diaphysis were collected aseptically from clinically healthy goats. The bones were sectioned into 1 cm fragments and stored at -20°C for subsequent hydrochloric acid (HCL) demineralization. A 70 mg portion of DBMc was used to fill the experimental bone defects. Twenty-four female adult New Zealand rabbits were divided into 2 groups: the MG (matrix group, left tibia) and CG (control group, right tibia). Additionally, they were separated into 4 groups with 6 animals, according to the period of analysis (15, 30, 60 and 90 days postoperatively). Using microCT, volumetric parameters were evaluated: bone volume, relationship between bone volume and total volume, bone surface area, relationship between bone surface area and total volume, number of trabeculae, trabecular thickness and trabecular separation. RESULTS: There was a statistically significant difference (P<0.05) between groups considering bone volume (BV) and bone:total volume (BV/TV), on 15, 30 and 90 days postoperatively. Control group showed a statistically significant superiority (P < 0.05) considering the mean of the variables bone surface (BS), number of trabeculae (Tb.N) and between bone surface and total volume (BS/TV) at 15 and 90 days. CONCLUSIONS: Caprine demineralized bone matrix was safe and tolerable. No signs of material rejection were seen macroscopically. It is an alternative for the treatment of bone defects when autologous graft is not available or in insufficient quantities.

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BACKGROUND: New bone formation and tissue remodeling are the major challenges in implantology today. Titanium meshes have demonstrated reconstructive potential for vertical bone gain. However, the soft tissue healing is technically sensitive to the surgical procedure. The combined usage of collagen membrane and specification of the meshes may ensure greater predictability. Therefore, this study aims to evaluate the influence of collagen membrane on the quality of the new bone formation in guided bone regeneration (GBR) procedures with different titanium meshes. METHODS: Twenty-eight Wistar rats were randomly allocated into four main experimental groups, according to mesh pore size in µm: Group P300 (titanium meshes, with 0.3-mm thickness and 3-mm pore size; n = 7); Group P175 (titanium meshes, with 0.3-mm thickness and 1.75-mm pore size; n = 7); Group P85: (titanium meshes, with 0.04-mm thickness and 0.85-mm pore size; n = 7); Group P15: (titanium meshes. with 0.04-mm thickness and 0.15-mm pore size; n = 7). The femurs of each animal were subdivided into test and control groups: Test: bovine bone graft associated with porcine collagen and collagen membrane was used; control: bovine bone graft associated with porcine collagen was used without association with collagen membrane. Bone quality evaluation by in vivo microtomography and histologic analysis were performed. RESULTS: Bone volume formation was similar between groups (P >0.05). However, the titanium meshes with pore size >1 mm demonstrated higher mineral bone density in comparison with meshes with pore size <1 mm (P <0.05), regardless of the combined usage of collagen membrane. All groups showed a spongy bone formation after 30 days. CONCLUSIONS: Combined usage of collagen membrane in GBR procedures with titanium mesh did not show improvements in new bone quality in rat femur model. However, titanium mesh pore size specifications may influence bone quality.

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Purpose To evaluate the use of demineralized bone matrix of caprine origin in experimental bone defects of the tibia in New Zealand rabbits. Methods Fragments of the tibia diaphysis were collected aseptically from clinically healthy goats. The bones were sectioned into 1 cm fragments and stored at -20°C for subsequent hydrochloric acid (HCL) demineralization. A 70 mg portion of DBMc was used to fill the experimental bone defects. Twenty-four female adult New Zealand rabbits were divided into 2 groups: the MG (matrix group, left tibia) and CG (control group, right tibia). Additionally, they were separated into 4 groups with 6 animals, according to the period of analysis (15, 30, 60 and 90 days postoperatively). Using microCT, volumetric parameters were evaluated: bone volume, relationship between bone volume and total volume, bone surface area, relationship between bone surface area and total volume, number of trabeculae, trabecular thickness and trabecular separation. Results There was a statistically significant difference (P 0.05) between groups considering bone volume (BV) and bone:total volume (BV/TV), on 15, 30 and 90 days postoperatively. Control group showed a statistically significant superiority (P < 0.05) considering the mean of the variables bone surface (BS), number of trabeculae (Tb.N) and between bone surface and total volume (BS/TV) at 15 and 90 days. Conclusions Caprine demineralized bone matrix was safe and tolerable. No signs of material rejection were seen macroscopically. It is an alternative for the treatment of bone defects when autologous graft is not available or in insufficient quantities.(AU)

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Abstract Purpose To evaluate the use of demineralized bone matrix of caprine origin in experimental bone defects of the tibia in New Zealand rabbits. Methods Fragments of the tibia diaphysis were collected aseptically from clinically healthy goats. The bones were sectioned into 1 cm fragments and stored at -20°C for subsequent hydrochloric acid (HCL) demineralization. A 70 mg portion of DBMc was used to fill the experimental bone defects. Twenty-four female adult New Zealand rabbits were divided into 2 groups: the MG (matrix group, left tibia) and CG (control group, right tibia). Additionally, they were separated into 4 groups with 6 animals, according to the period of analysis (15, 30, 60 and 90 days postoperatively). Using microCT, volumetric parameters were evaluated: bone volume, relationship between bone volume and total volume, bone surface area, relationship between bone surface area and total volume, number of trabeculae, trabecular thickness and trabecular separation. Results There was a statistically significant difference (P<0.05) between groups considering bone volume (BV) and bone:total volume (BV/TV), on 15, 30 and 90 days postoperatively. Control group showed a statistically significant superiority (P < 0.05) considering the mean of the variables bone surface (BS), number of trabeculae (Tb.N) and between bone surface and total volume (BS/TV) at 15 and 90 days. Conclusions Caprine demineralized bone matrix was safe and tolerable. No signs of material rejection were seen macroscopically. It is an alternative for the treatment of bone defects when autologous graft is not available or in insufficient quantities.

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Para tentar preservar as dimensões teciduais (ósseas e de tecido mole) do alvéolo até o momento da instalação do implante pode-se lançar mão de técnicas de preservação de alvéolos dentários imediatamente após a exodontia. Dentre as diversas técnicas e biomateriais existentes, a associação de um substituto ósseo (Bio-Oss® Collagen) com um selador do alvéolo (Mucograft® Seal) vem apresentando resultados satisfatórios na literatura. O objetivo do presente trabalho é apresentar uma breve revisão de literatura e um relato de caso clínico usando essa abordagem. Os principais achados da revisão de literatura é que a utilização desses substitutos mucosos e ósseos são a redução do tempo cirúrgico e diminuição da morbidade e desconforto pós-operatório do paciente, já que não necessita da área doadora. No relato de caso, os resultados clínicos de 15 e 60 dias de pós-operatório mostraram que essa abordagem foi eficaz em manter as dimensões ósseas e de tecido queratinizado do alvéolo. (AU)

In an effort to preserve the alveolar tissue dimensions (bone and soft tissue) until the time of implant installation can make use of ridge preservation techniques after the dental extraction. Among the many techniques and biomaterials the association of a bone substitute (Bio-Oss® Collagen) with an alveolar sealer (Mucograft® Seal) has shown satisfactory results in the literature.The objective of this study is present a brief literature review and a clinical case report using this approach. The main findings of the literature review are that the use of these mucosal and bone substitutes are the reduction of surgical time and decrease of the postoperative morbidity and discomfort of the patient, since it does not need the donor area. In the case reportthe clinical results of 15 and 60 days postoperatively showed that this approach was effective in maintaining bone dimensions and keratinized alveolar tissue (AU)

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A regeneração periodontal tem como objetivo recuperar as estruturas perdidas (osso alveolar, cemento e ligamento periodontal) como sequelas da doença periodontal. O conhecimento da Matriz Derivada do Esmalte (MDE) tem na literatura uma ampla aplicação, porém sua relação direta associada aos vidros bioativos é pouco caracterizada em todas suas vias, nesse contexto este estudo teve como proposta baseada numa revisão literária por meio de bases de dados (Pubmed, Scielo, lilacs), discutir aspectos importantes sobre a avaliação da efetividade clínica do vidro bioativo em combinação com a MDE (Emdogain) principalmente em defeitos infra-ósseos. O Emdogain (EMD) sozinho ou em associação a outros biomaterais de enxertia parece promover ganhos na regeneração tecidual de tecidos perdidos pela periodontite, porém sua associação tem-se poucos resultados significativos que justifiquem sua ampla utilização, sua indicação deve estar baseada em um bom diagnóstico periodontal e da morfologia do defeito infraósseo. Assim, tornam-se necessários mais estudos para elucidar interações e mecanismos celulares envolvidos no complexo de ação para justificar o seu uso.(AU)

Periodontal regeneration aims to recover the lost structures (alveolar bone, cementum and periodontal ligament) as sequelae of periodontal disease. The knowledge derived from the enamel matrix (EMD) is in the literature a wide application, but its direct relationship associated with bioactive glass is poorly characterized in all its way in this context this study was proposed based on a literature review through databases (Pubmed, Scielo, lilacs), discuss important aspects of the evaluation of the clinical effectiveness of bioactive glass in combination with EMD (Emdogain) mainly intraosseous defects.Emdogain (EMD) alone or in association with other biomaterials of grafting appears to promote gains in the tissue regeneration of lost tissues by periodontitis, but its association has few significant results that justify its wide use, its indication must be based on a good periodontal diagnosis and infraosseous defect morphology. Thus, further studies are needed to elucidate interactions and cellular mechanisms involved in the action complex to justify its use.(AU)

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The aim of this randomized controlled clinical study was to compare the extended flap technique (EFT) with the coronally advanced flap technique (CAF) using a porcine collagen matrix (PCM) for root coverage. Twenty patients with two bilateral gingival recessions, Miller class I or II on non-molar teeth were treated with CAF+PCM (control group) or EFT+PCM (test group). Clinical measurements of probing pocket depth (PPD), clinical attachment level (CAL), recession height (RH), keratinized tissue height (KTH), keratinized mucosa thickness (KMT) were determined at baseline, 3 and 6 months post-surgery. At 6 months, the mean root coverage for test group was 81.89%, and for control group it was 62.80% (p<0.01). The change of recession depth from baseline was statistically significant between test and control groups, with an mean of 2.21 mm gained at the control sites and 2.84 mm gained at the test sites (p=0.02). There were no statistically significant differences for KTH, PPD or CAL comparing the two therapies. The extended flap technique presented better root coverage than the coronally advanced flap technique when PCM was used.

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