Performance of panoramic radiography compared with computed tomography in the evaluation of pathological changes in the maxillary sinuses: a systematic review and meta-analysis.

OBJECTIVE: A systematic review was performed to evaluate the performance of panoramic radiography (PR) vs CT or cone beam CT (CBCT) in the diagnosis of pathological maxillary sinuses. METHODS: This review was registered in the PROSPERO database under the number CRD42020211766. Observational studies that compared PR with CT/CBCT were used to evaluate pathological changes in the maxillary sinuses. A complete search of seven primary databases and gray literature was carried out. The risk of bias was assessed according to the Newcastle-Ottawa tool, and the GRADE tool was used to assess the quality of evidence. A binary meta-analysis was performed to assess the effectiveness of evaluating pathological alterations in the maxillary sinuses in PR and CT/CBCT. RESULTS: Seven studies were included in our study, out of which four were included in a quantitative analysis. All studies were classified as low risk of bias. Five studies compared PR with CBCT and two studies compared PR to CT. The most common pathological alteration in maxillary sinuses reported was mucosal thickening. CT/CBCT was seen to be the most effective method for assessing pathological changes in the maxillary sinus when compared to PR (RR = 0.19, 95% confidence interval [CI] = 0.05 to 0.70, p = 0.01). CONCLUSION: CT/CBCT are the most appropriate imaging methods to evaluate pathological changes in the maxillary sinuses, while PR is still limited in the evaluation of these changes being considered only for initial diagnosis.

Microtomographic, histomorphometric, and molecular features show a normal alveolar bone healing process in iNOS-deficient mice along a compensatory upregulation of eNOS and nNOS isoforms.

METHODOLOGY: Inducible nitric oxide synthase (iNOS) is one of the enzymes responsible for the synthesis of nitric oxide (NO), which is an important signaling molecule with effects on blood vessels, leukocytes, and bone cells. However, the role of iNOS in alveolar bone healing remains unclear. This study investigated the role of iNOS in alveolar bone healing after tooth extraction in mice. C57Bl/6 wild type (WT) and iNOS genetically deficient (iNOS-KO) mice were subjected to upper incision tooth extraction, and alveolar bone healing was evaluated by micro-computed tomography (µCT) and histological/histomorphometric, birefringence, and molecular methods. RESULTS: The expression of iNOS had very low control conditions, whereas a significant increase is observed in healing sites of WT mice, where iNOS mRNA levels peak at 7d time point, followed by a relative decrease at 14d and 21d. Regarding bone healing, both WT and iNOS-KO groups showed the usual phases characterized by the presence of clots, granulation tissue development along the inflammatory cell infiltration, angiogenesis, proliferation of fibroblasts and extracellular matrix synthesis, bone neoformation, and remodeling. The overall micro-computed tomography and histomorphometric and birefringence analyses showed similar bone healing readouts when WT and iNOS-KO strains are compared. Likewise, Real-Time PCR array analysis shows an overall similar gene expression pattern (including bone formation, bone resorption, and inflammatory and immunological markers) in healing sites of WT and iNOS-KO mice. Moreover, molecular analysis shows that nNOS and eNOS were significantly upregulated in the iNOS-KO group, suggesting that other NOS isoforms could compensate the absence of iNOS. CONCLUSION: The absence of iNOS does not result in a significant modulation of bone healing readouts in iNOS-KO mice. The upregulation of nNOS and eNOS may compensate iNOS absence, explaining the similar bone healing outcome in WT and iNOS-KO strains.

Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas / Prevalence of juxta-apical radiolucency and association/relations with the lower third molar in panoramic radiography

Objetivo: Avaliar a prevalência da radiolucência justa-apical (RJA) e sua relação com os terceiros molares inferiores, em 1054 radiografias panorâmicas. Métodos: A amostra foi constituída por radiografias panorâmicas digitais de indivíduos maiores de 18 anos, com pelo menos um terceiro molar inferior. As imagens foram analisadas para a presença de RJA em relação à corticalização, localização, relação com o canal mandibular, angulação e profundidade de impactação do terceiro molar. Os dados foram analisados através de estatística descritiva e pelo teste Qui-quadrado, sendo que valores de p < 0,05 foram considerados como significativos. Resultados:Foi encontrada uma prevalência de 2,75% de RJA, sendo predominante no sexo feminino (p = 0,01). A RJA foi visualizada em maior número corticalizada (58,63%), lateroapical (48,27%), em dentes parcialmente intraósseo (68,97%) e mesioangulados (55,17%). Em relação ao canal mandibular, houve maior prevalência na posição sobreposta ao canal mandibular (65,52%). Conclusão: A prevalência de RJA foi de 2,75% do total de 1054 radiografias panorâmicas avaliadas. Em relação ao canal mandibular, apresentou maior prevalência sobreposto. Além disso, a maior parte das RJA se apresentaram corticalizadas, em posição lateroapical, associada a dentes em posição mesioangular. Descritores: Radiografia panorâmica. Dente serotino. Nervo mandibular.Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas

Aim: To evaluate the prevalence of juxta-apical radiolucency (JAR) and its relationship with the lower third molars and adjacent structures, in 1,054 panoramic radiographs. Methods: The sample consisted of digital panoramic radiographs of individuals over 18 years of age, with at least one lower third molar. The images were analyzed for the presence of JAR in relation to corticalization, location, impaction depth, relationship with the mandibular canal, angulation, and impaction of the third molar. Data were analyzed using descriptive statistics and the chi-square test, and values of p < 0.05 were considered significant.Results: A prevalence of 2.75% of JAR was found, with a statistical difference between JAR and gender (p = 0.01), which proved to be predominant in females. The JAR was seen in greater numbers as corticalized (58.63%), lateroapical (48.27%), and mesioangulated (55.17%), as well as in erupted teeth (31.03%). In relation to the mandibular canal, it presented a higher prevalence when superimposed upon the mandibular canal (65.52%). Conclusions:The prevalence of RJA was 2.75% of the 1,054 evaluated panoramic radiographs. In relation to the mandibular canal, it presented a higher prevalence of superimposition. In addition, most of the RJA were corticalized, in a lateroapical position, associated with teeth in a mesioangular position. Uniterms: Panoramic radiography. Third molar. Mandibular nerve.

Microtomographic, histomorphometric, and molecular features show a normal alveolar bone healing process in iNOS-deficient mice along a compensatory upregulation of eNOS and nNOS isoforms

Abstract Inducible nitric oxide synthase (iNOS) is one of the enzymes responsible for the synthesis of nitric oxide (NO), which is an important signaling molecule with effects on blood vessels, leukocytes, and bone cells. However, the role of iNOS in alveolar bone healing remains unclear. This study investigated the role of iNOS in alveolar bone healing after tooth extraction in mice. Methodology C57Bl/6 wild type (WT) and iNOS genetically deficient (iNOS-KO) mice were subjected to upper incision tooth extraction, and alveolar bone healing was evaluated by micro-computed tomography (μCT) and histological/histomorphometric, birefringence, and molecular methods. Results The expression of iNOS had very low control conditions, whereas a significant increase is observed in healing sites of WT mice, where iNOS mRNA levels peak at 7d time point, followed by a relative decrease at 14d and 21d. Regarding bone healing, both WT and iNOS-KO groups showed the usual phases characterized by the presence of clots, granulation tissue development along the inflammatory cell infiltration, angiogenesis, proliferation of fibroblasts and extracellular matrix synthesis, bone neoformation, and remodeling. The overall micro-computed tomography and histomorphometric and birefringence analyses showed similar bone healing readouts when WT and iNOS-KO strains are compared. Likewise, Real-Time PCR array analysis shows an overall similar gene expression pattern (including bone formation, bone resorption, and inflammatory and immunological markers) in healing sites of WT and iNOS-KO mice. Moreover, molecular analysis shows that nNOS and eNOS were significantly upregulated in the iNOS-KO group, suggesting that other NOS isoforms could compensate the absence of iNOS. Conclusion The absence of iNOS does not result in a significant modulation of bone healing readouts in iNOS-KO mice. The upregulation of nNOS and eNOS may compensate iNOS absence, explaining the similar bone healing outcome in WT and iNOS-KO strains.

A novel rat model of denture stomatitis and the role of antibiotics in the development of the disease.

This study compared different conditions to establish a rat model of denture stomatitis. Immunocompetent Wistar rats were divided into two groups (n = 35): Tetracycline = administration of 0.83 mg/ml of tetracycline hydrochloride 7 days before induction of denture stomatitis and amoxicillin = administration of 0.156 mg/ml of amoxicillin with clavulanic acid 4 days before induction of denture stomatitis. A suspension of Candida albicans was inoculated on the palate followed by the use of a palatal device contaminated with C. albicans inoculum for 4 days to induce denture stomatitis. As controls, some rats were not submitted to any procedure or used a sterile palatal device for 4 days. The development of denture stomatitis was confirmed by visual analysis, colony-forming units per milliliter (CFU/ml) count, histopathological and immunohistochemical analyses, and through myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) assays. Rats were euthanized right after device removal (T0), 4 (T4), or 6 (T6) days after device removal. Tetracycline improved the development of the disease, with more severe clinical signs at T0. Similar results were observed in the CFU/ml count and in the histometric and immunohistochemical analyses. Higher MPO expression was detected in the palates of the tetracycline group (P = .006). Despite the subtle differences between antibiotics, tetracycline showed better results in inducing and maintaining denture stomatitis for at least 4 days after device removal.

Denture stomatitis is an oral inflammatory disease with high recurrence rates. Different animal models have been reported in the literature, but some gaps still need to be addressed. A reproducible in vivo model should be established to test new treatment approaches.

Absence of medication-related jaw osteonecrosis after treatment with strontium ranelate in ovariectomized rats.

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.

Implant Osseointegration in Grafted Autogenous Bone Blocks Fixed with Screws and Cyanoacrylate-Based Adhesive: Histomorphometric and Micro-CT Analyses.

PURPOSE: To evaluate implant osseointegration in grafted autogenous bone blocks fixed with cyanoacrylate-based adhesive and screws. Also, grafted bone fixed either with an adhesive or screw was evaluated. MATERIALS AND METHODS: Two surgical defects in the parietal region of rabbits (n = 12) were performed in each animal. Autogenous bone blocks obtained were fixed anteriorly with a screw or cyanoacrylate-based adhesive. After 30 and 45 days of grafting procedures, implants were placed in bone blocks. Histomorphometric and microcomputed tomography (micro-CT) analyses of the implant area were performed at 30 days after implant surgery in the screw (n = 6) and adhesive (n = 6) groups. Histomorphometric analyses of bone-grafted areas were performed at 60 and 75 days in the screw (n = 6) and adhesive (n = 6) groups. Histomorphometric evaluations were carried out in implant and grafted bone areas. The micro-CT parameters evaluated were bone-to-implant contact, bone area fraction occupancy, bone volume fraction, trabecular thickness, trabecular separation, and trabecular number. RESULTS: No differences were observed in the micro-CT parameters for the screw and adhesive groups in all experimental periods. However, an increased quantity of immature bone volume was observed on the adhesive group in the grafted area after 75 days. The grafted area in the screw group (75 days) presented a decrease in the volume density of the immature bone compared with the screw group (60 days). There were no differences in both groups and experimental periods in soft tissue in the grafted area. CONCLUSION: No differences were observed in the osseointegration of implants placed in grafted autogenous bone blocks fixed with cyanoacrylate-based adhesive and screws. Therefore, osseointegration in autogenous bone fixed with cyanoacrylate-based adhesive is viable.

Effect of pentoxifylline and α-tocopherol on medication-related osteonecrosis of the jaw in rats: Before and after dental extraction.

OBJECTIVE: Evaluate the effect of pentoxifylline and α-tocopherol administration in the prevention or treatment of medication-related jaw osteonecrosis (MRONJ). METHODOLOGY: Sixty Wistar rats were divided into three prevention (C-prev, BP-prev and BP/PT-prev) and three treatment groups (C-treat, BP-treat and BP/PT-treat), n = 10. The animals in the BP-prev, BP/PT-prev, BP-treat and BP/PT-treat groups received zoledronic acid (0.1 mg/kg) for 12 weeks, while the animals in the C-prev and C-treat groups received saline solution. At week 6, all animals underwent tooth extraction. Between week 5 and week 12, the BP/PT-prev group was treated with pentoxifylline (50 mg/kg/day) and α-tocopherol (80 mg/kg/day), with euthanasia at the end of week 12. The BP/PT-treat group received the same drug protocol, but it was performed between week 12 and week 16, with euthanasia at the end of week 16. Afterwards, the presence of osteonecrosis was evaluated by clinical analysis, radiographic and histological. RESULTS: BP/PT-treat group showed a reduction in the histological incidence of osteonecrosis by 50%, decrease the percentage of empty osteocyte gaps and the necrotic area, decrease the presence of bone sequestration and increase the number of osteocytes and alveolar blood flow (p < 0.05). However, BP/PT-prev group showed only a reduction in the necrotic area percentage when compared to BP-prev (p < 0.05). CONCLUSIONS: Pentoxifylline and α-tocopherol administration before tooth extraction was not effective in preventing MRONJ. However, this drug protocol was able to reduce MRONJ manifestation when administrate after discontinuation of bisphosphonate, thus it can be considered as a viable strategy for the treatment of this pathological condition.

Dental management in the Intensive Care Unit in the treatment of toxic epidermal necrolysis associated with phenytoin: case report / Manejo odontológico na Unidade de Terapia Intensiva no tratamento da necrólise epidérmica tóxica associada a fenitoína: relato de caso

ABSTRACT Stevens-Johnson syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are adverse reactions, usually medicine-related, in which extensive and painful mucocutaneous lesions are formed. Oral lesions are characterized by the presence of erosions and ulcers. The treatment usually requires intensive care in a hospital setting, where the Dentist is essential in the multidisciplinary team, as he will act in the treatment of oral lesions. In this article, a 26-year-old female patient was reported, who presented TEN-compatible mucocutaneous lesions associated with the drug Phenytoin and required admission to a Teaching Hospital. The treatment consisted of the immediate suspension of the Phenytoin use and systemic therapy with corticosteroids and immunosuppressants. Oral lesions were monitored by the hospital dentistry team. The procedures adopted were: oral hygiene with 0.12% non-alcoholic Chlorhexidine Digluconate solution, hydration of the oral tissue with an essential fatty acid, application of frozen chamomile tea, and prescription of topical Triamcinolone Acetonide. Also, low-level laser therapy sessions (red and infrared) were performed. Oral lesions evolved with significant improvement. In this case, the importance of the Dentist in the multi-professional team is demonstrated. Although there is no protocol, the procedures used in the present case can be an alternative to therapies used in SSJ and TEN oral lesions.

RESUMO A Síndrome de Stevens Johnson (SSJ) e a Necrólise Epidérmica Tóxica (NET) são reações adversas, geralmente medicamentosas. Na pele, formam-se máculas que se tornam pápulas, vesículas e bolhas, além de eritema extenso e desprendimento da epiderme. As lesões bucais caracterizam-se pela presença de erosões e úlceras dolorosas. O tratamento geralmente é realizado em âmbito hospitalar, com necessidade de cuidados intensivos, onde o Cirurgião-dentista é fundamental na equipe multiprofissional, pois atuará na terapêutica das lesões bucais. Neste artigo foi relatado o caso de uma paciente do sexo feminino, de 26 anos, a qual apresentou lesões mucocutâneas compatíveis com NET associadas ao medicamento Fenitoína e necessitou de internamento em um Hospital Universitário. O tratamento realizado foi a suspensão imediata do fármaco desencadeador, além de terapia sistêmica com corticóide e imunossupressor. As lesões bucais foram acompanhadas pela equipe de odontologia hospitalar. As condutas adotadas foram: higiene bucal com solução de Digluconato de Clorexidina 0,12% não alcoólica, hidratação da mucosa bucal com Ácido Graxo Essencial, aplicação de raspas de chá de gelo de camomila e prescrição de Triancinolona Acetonida tópica. Além disso, foram realizadas sessões de laserterapia de baixa intensidade (vermelho e infravermelho). As lesões bucais evoluíram com melhora significativa. A paciente permaneceu internada durante 22 dias, sendo 12 em Unidade de Terapia Intensiva. Este caso demonstra a importância do Cirurgião-dentista na equipe multiprofissional. Apesar de não haver um protocolo para as lesões bucais, as condutas utilizadas no presente caso podem ser uma alternativa de terapêuticas utilizadas em lesões de SSJ e NET.

Absence of medication-related jaw osteonecrosis after treatment with strontium ranelate in ovariectomized rats

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.

Prevalência das posições e grau de dificuldade cirúrgica de terceiros molares inferiores: um estudo radiográfico retrospectivo / Prevalence of positions and degree of surgical difficulty in lower third molars: a retrospective radiographic study

Objetivo: Os objetivos deste estudo foram avaliar a prevalência do posicionamento dos terceiros molares inferiores seguindo a classificação de Winter e Pell & Gregory, e determinar os níveis de dificuldade para a exodontia através do índice de Pederson. Materiais e Métodos: Estudo radiográfico, transversal e retrospectivo avaliou 100 radiografias panorâmicas provenientes dos prontuários odontológicos atendidos nos ambulatórios de Cirurgia bucal, de pacientes entre 15 e 61 anos de idade, no período de 2015 a 2017. As radiografias panorâmicas foram avaliadas por meio do software ImageJquanto aos posicionamentos dos terceiros molares inferiores pela classificação de Winter e Pell & Gregory, enquanto o nível de dificuldade foi avaliado pelo índice de Pederson. Os resultados obtidos foram submetidos à análise estatística descritiva. Resultados: A maior prevalência de terceiros molares inclusos foi observada em mulheres, com idade média de 26 anos. Quanto a posição dos dentes inclusos, a posições vertical (44,0%), nível A (74,7%) e classe III (69,9%) foram as mais prevalentes. Na escala de Pederson, a dificuldade cirúrgica "muito difícil" foi a mais encontrada. Discussão: nossos resultados sugerem estabelecer um melhor planejamento cirúrgico e prognóstico aos pacientes, minimizando a possibilidade de complicações durante e após as extrações de terceiros molares inferiores. Conclusão: Ambas classificações auxiliam o cirurgião-dentista a estabelecer um melhor planejamento e prognóstico aos pacientes. A aplicabilidade das radiografias panorâmicas, associados a avaliação clínica, justificam menores possibilidades de complicações pós-cirúrgicas em terceiro molar inferior.

Aim: The objectives of this study were to evaluate the prevalence of the mandibular third molars position in according to the Winter and Pell & Gregory classification, and to determine the levels of difficulty for exodontia through the Pederson index. Materials and Methods: Radiographic, cross-sectional and retrospective study evaluated 100 panoramic radiographs of patients between 15 and 61 years old, from dental records seen at the Oral Surgery department in the period from 2015 to 2017. The panoramic radiographs were evaluated using ImageJ software regarding the positioning of the lower third molars by the Winter and Pell & Gregory classification, while the level of difficulty was evaluated by the Pederson index. The results obtained were submitted to descriptive statistical analysis.Results: The highest prevalence of included third molars was observed in women, with an age average of 26 years. Regarding the position of the included teeth, the vertical position (44.0%), level A (74.7%), and class III (69.9%) were the most prevalent. In the Pederson scale, the "very difficult" surgical difficulty was the most found. Discussion: results suggest establishing better surgical planning and prognosis for patients, minimizing the possibility of complications during and after extractions of mandibular third molars.Conclusion: Both classifications help the dental surgeon to establish better planning and prognosis for patients. The applicability of panoramic radiographs, associated with clinical evaluation, justifies a fewer possibility of complications in the lower third molar post-extraction

Histological Comparison between Biphasic Calcium Phosphate and Deproteinized Bovine Bone on Critical-Size Bone Defects.

The limited options for bone repair have led to an extensive research of the field and the development of alloplastic and xenogeneic grafts. The purpose of this study was to evaluate bone repair with two bone substitutes: deproteinized bovine bone (DBB) and biphasic calcium phosphate ceramic (BCP) in critical-size defect. A total of 8-mm defects were made in the parietal bones of rabbits (n=12). The animals were divided into three experimental groups: sham (defect filled with a blood clot), DBB (defect filled with DBB), and BCP (defect filled with BCP). After the experimental periods of 15 and 45 days, the animals were euthanized and submitted to histomorphometric analysis. The total defect area, mineralized tissue area, biomaterial area, and soft tissue area were evaluated. A greater amount of immature bone tissue and biomaterial particles were observed in the BCP group compared to DBB and sham at 45 days (p<0.05). There was no difference in the qualitative pattern of bone deposition between DBB and BCP. However, the sham group did not show osteoid islands along with the defect, presenting a greater amount of collagen fibers as well in relation to the DBB and BCP groups. There was a greater number of inflammatory cells in the DBB at 45 days compared to BCP and sham groups. In conclusion, BCP and DBB are options for optimizing the use of bone grafts for maxillofacial rehabilitation. Bone defects treated with BCP showed greater deposition of bone tissue at 45 days.

Histological comparison between biphasic calcium phosphate and deproteinized bovine bone on critical-size bone defects

Abstract The limited options for bone repair have led to an extensive research of the field and the development of alloplastic and xenogeneic grafts. The purpose of this study was to evaluate bone repair with two bone substitutes: deproteinized bovine bone (DBB) and biphasic calcium phosphate ceramic (BCP) in critical-size defect. A total of 8-mm defects were made in the parietal bones of rabbits (n=12). The animals were divided into three experimental groups: sham (defect filled with a blood clot), DBB (defect filled with DBB), and BCP (defect filled with BCP). After the experimental periods of 15 and 45 days, the animals were euthanized and submitted to histomorphometric analysis. The total defect area, mineralized tissue area, biomaterial area, and soft tissue area were evaluated. A greater amount of immature bone tissue and biomaterial particles were observed in the BCP group compared to DBB and sham at 45 days (p<0.05). There was no difference in the qualitative pattern of bone deposition between DBB and BCP. However, the sham group did not show osteoid islands along with the defect, presenting a greater amount of collagen fibers as well in relation to the DBB and BCP groups. There was a greater number of inflammatory cells in the DBB at 45 days compared to BCP and sham groups. In conclusion, BCP and DBB are options for optimizing the use of bone grafts for maxillofacial rehabilitation. Bone defects treated with BCP showed greater deposition of bone tissue at 45 days.

Resumo As opções limitadas para reparo ósseo levaram ao desenvolvimento de abrangente pesquisa na área de enxertos aloplásticos e xenogênicos. O objetivo deste estudo foi avaliar o reparo ósseo com dois substitutos ósseos: osso bovino desproteinizado (DBB) e cerâmica fosfática de cálcio bifásica (BCP) em defeito de tamanho crítico. Material e métodos: defeitos críticos de 8 mm foram feitos nos ossos parietais de coelhos (n=12). Os animais foram divididos em três grupos experimentais: sham (defeito preenchido com coágulo sanguíneo), DBB (defeito preenchido com DBB) e BCP (defeito preenchido com BCP). Após os períodos experimentais de 15 e 45 dias, os animais foram sacrificados e submetidos à análise histomorfométrica. Foram avaliadas a área total de defeitos, área de tecidos mineralizados, área de biomateriais e área de tecidos moles. Resultados: maior quantidade de tecido ósseo imaturo e de partículas de biomaterial foram observados no grupo BCP em comparação aos grupos DBB e sham aos 45 dias (p<0,05). Não houve diferença no padrão qualitativo de deposição óssea entre DBB e BCP. Ainda, o grupo sham não apresentou ilhas osteóides ao longo do defeito, apresentando maior quantidade de fibras colágenas em relação aos grupos DBB e BCP. Houve maior quantidade de células inflamatórias no DBB aos 45 dias em comparação aos grupos BCP e sham. Conclusões: BCP e DBB são opções para otimizar o uso de enxertos ósseos na reabilitação de pacientes. Defeitos ósseos tratados com BCP mostraram maior deposição de tecido ósseo aos 45 dias.

Effects of low-dose aspirin on the osseointegration process in rats.

BACKGROUND: Several drugs are capable of promoting changes in bone metabolism. The aim of this study was to evaluate the effect of long-term low-dose aspirin (LDA) therapy on implant osseointegration. METHODS: Male Wistar rats were divided into 4 groups (n = 8/group) according to oral gavage solution received prior (42 days) to the implant surgery on the tibia. The control group was treated with saline solution for 7 (CG-7) and 28 (CG-28) days. The use of low-dose aspirin was performed in AG groups (6.75 mg/kg of aspirin) for 7 (AG-7) and 28 (AG-28) days. After experimental periods, histomorphometric evaluation of bone-to-implant contact (BIC) and the bone area between threads (BABT) was performed. RESULTS: Reduced BIC values were detected in AG-7 (62.8% ± 17.1) group compared to AG-28 (91.9% ± 5.4), CG-7 (82.7% ± 15.2), and CG-28 (89.9% ± 9.7). BABT evaluation revealed lower values in AG-7 (70.9% ± 15.2) compared to AG-28 (95.4% ± 3.7) and CG-28 (87.1% ± 10.2) groups. CONCLUSIONS: The treatment with low doses of aspirin promoted a discrete inhibitory effect in the early stages (7 days) of repair after implant placement, specifically in the bone deposition. However, these effects were not detected in the late stages (28 days), considering BIC and BABT parameters.

Experimental Acute Sepsis Reduced Number of Osteocalcin Immunolabeled Cells in Periodontal Ligament.

The aim of this study was to evaluate the effect of acute sepsis in the periodontal ligament, alveolar and furcation bone in absence of periodontitis induction through histological and immunohistochemical analyses. A septic rat model was established by cecal ligation and puncture (CLP). Twelve rats were randomly divided into CLP (n=6) and Sham (n=6) groups. The animals were euthanized at 24 h and hemimandibles were submitted to histomorfometric (bone matrix, collagenous fibers, fibroblasts, osteocytes, inflammatory cells, and blood vessels) and immunohistochemical (BMP-2/4, RANKL and osteocalcin) evaluation in alveolar bone, furcation bone and periodontal ligament. Our results demonstrated that histomorphometric parameters were similar in alveolar bone, furcation bone and periodontal ligament of Sham and CLP rats. Regarding to immunohistochemical analyses, the number of BMP-2/4 and RANKL immunolabeled cells was also similar in both groups. Furthermore, it was detected a reduction in the osteocalcin immunolabeled cells in periodontal ligaments of CLP compared to Sham rats (p=0.0014). In conclusion, the acute sepsis induction resulted in reduced number of osteocalcin labelled cells in periodontal ligament region. Moreover, no significant histological differences were observed in the periodontium of rats under acute sepsis. Considering the role of osteocalcin in bone remodeling, the study contributes to revealing the importance of careful periodontal evaluation in the presence of sepsis.

Experimental acute sepsis reduced number of osteocalcin immunolabeled cells in periodontal ligament

Abstract The aim of this study was to evaluate the effect of acute sepsis in the periodontal ligament, alveolar and furcation bone in absence of periodontitis induction through histological and immunohistochemical analyses. A septic rat model was established by cecal ligation and puncture (CLP). Twelve rats were randomly divided into CLP (n=6) and Sham (n=6) groups. The animals were euthanized at 24 h and hemimandibles were submitted to histomorfometric (bone matrix, collagenous fibers, fibroblasts, osteocytes, inflammatory cells, and blood vessels) and immunohistochemical (BMP-2/4, RANKL and osteocalcin) evaluation in alveolar bone, furcation bone and periodontal ligament. Our results demonstrated that histomorphometric parameters were similar in alveolar bone, furcation bone and periodontal ligament of Sham and CLP rats. Regarding to immunohistochemical analyses, the number of BMP-2/4 and RANKL immunolabeled cells was also similar in both groups. Furthermore, it was detected a reduction in the osteocalcin immunolabeled cells in periodontal ligaments of CLP compared to Sham rats (p=0.0014). In conclusion, the acute sepsis induction resulted in reduced number of osteocalcin labelled cells in periodontal ligament region. Moreover, no significant histological differences were observed in the periodontium of rats under acute sepsis. Considering the role of osteocalcin in bone remodeling, the study contributes to revealing the importance of careful periodontal evaluation in the presence of sepsis.

Resumo O objetivo deste estudo foi avaliar o efeito da sepse aguda no ligamento periodontal, osso alveolar e osso da furca por meio de análise histológica e imunohistoquímica. O modelo de sepse em ratos foi estabelecido pelo procedimento de ligação e perfuração do ceco (CLP). Doze ratos foram divididos de forma randomizada em ratos sépticos (n=6) e controle - grupo Sham (n=6). Os animais foram eutanasiados após 24 horas e suas hemimandíbulas foram submetidas aos procedimentos histotécnicos para análise histomorfométricos (matriz óssea, fibras colágenas, fibroblastos, osteócitos, células inflamatórias e vasos sanguíneos) e imunohistoquímicos (BMP-2/4, RANKL e osteocalcina) no osso alveolar, osso de furca e ligamento periodontal. Nossos resultados demonstraram que os parâmetros histomorfométricos foram similares no osso alveolar, osso de furca e ligamento periodontal dos animais do grupo sepse e do grupo Sham. Em relação à análise por imunohistoquímica, o número de células imunomarcadas para BMP-2/4 e RANKL também foi similar em ambos os grupos. Entretanto, houve redução (p=0.0014) no número de células imunomarcadas para osteocalcina no ligamento periodontal de ratos sépticos em relação ao grupo Sham. Como conclusão, o estabelecimento de sepse aguda resultou em um número reduzido de células imunomarcadas para osteocalcina na região do ligamento periodontal (p=0,0014). Além disso, não foram observadas diferenças histológicas significativas no periodonto de ratos na presença de sepse aguda. Considerando o papel da osteocalcina na remodelação óssea, este estudo contribui para revelar a importância da avaliação periodontal cuidadosa na presença de sepse.

Osteoconductivity of Biphasic Calcium Phosphate Ceramic Improves New Bone Formation: A Histologic, Histomorphometric, Gene Expression, and Microcomputed Tomography Study.

PURPOSE: The purpose of this study was to evaluate bone repair with two bone substitutes, deproteinized bovine bone and biphasic calcium phosphate ceramics, associated with autogenous bone. MATERIALS AND METHODS: The experimental groups were as follows: autogenous bone only (AB), autogenous bone/deproteinized bovine bone (1:1), and autogenous bone/biphasic calcium phosphate ceramic (1:1). After 30, 60, and 90 days, animals were euthanized and samples were collected for microcomputed tomography (micro-CT), histologic, histomorphometric, and expression analyses of VEGFA, RUNX2, ALP, COL1A1, OCN, PHEX, RANKL, and OPG genes by real-time polymerase chain reaction (PCR) array. RESULTS: Histomorphometric analysis showed no difference in the amount of immature bone between AB and AB/biphasic calcium phosphate ceramic at 30 and 60 days. There was less mature bone formation in the AB/deproteinized bovine bone at 60 days compared with AB/biphasic calcium phosphate ceramic and AB, and a lower amount of immature bone in the AB/deproteinized bovine bone at 30 and 60 days compared with the AB (P ≤ .05). Micro-CT analysis showed higher immature bone volume (BVI) in the AB/biphasic calcium phosphate ceramic at 60 days and lower BVI at 90 days (P ≤ .05). Molecular analysis showed a lower expression of all genes in the AB/deproteinized bovine bone and AB/biphasic calcium phosphate ceramic compared with AB at all time points. A greater expression of RANKL was found in the AB/deproteinized bovine bone compared with AB/biphasic calcium phosphate ceramic at 30 days (P ≤ .05), and a lower expression of the OC, RUNX2, and ALP genes in AB/deproteinized bovine bone and AB/biphasic calcium phosphate ceramic was found compared with AB at all time points (P ≤ .05). CONCLUSION: The use of biphasic calcium phosphate ceramic resulted in greater immature bone formation than deproteinized bovine bone at an early assessment. The studied bone regeneration genes were downregulated in comparison to the control.

Avaliação histológica e tomográfica do enxerto xenógeno em bloco para o preenchimento do seio maxilar / Histological and tomographic evaluation of the xenograft block for filling the maxillary sinus

O objetivo desse estudo foi avaliar, por meio de exame tomográfico e histológico, o comportamento do enxerto de osso bovino desproteinizado em cirurgias de elevação de soalho de seio maxilar. A amostra foi constituída por 7 pacientes do gênero feminino que necessitavam de instalação de implantes osseointegrados para reabilitação do rebordo posterior edêntulo total ou parcial da maxila e apresentavam pneumatização do seio maxilar com necessidade de aumento vertical através de técnicas de enxertia. Os pacientes foram submetidos à cirurgia de elevação de soalho de seio maxilar, sendo que a cavidade sinusal foi preenchida com enxerto bovino desproteinizado em forma de bloco que foi mantido fixo dentro do seio maxilar por meio de um parafuso de fixação do enxerto. Após 6 meses do procedimento cirúrgico, foi executada uma avaliação tomográfica para verificação do aumento da disponibilidade de tecido ósseo e análise histométrica das biópsias para avaliação da composição do tecido reparado. Verificou-se que houve aumento da altura do rebordo alveolar. Antes do procedimento cirúrgico era de 4,10 ± 2,03 mm e no momento da instalação dos implantes era de 19,04 ± 2,45 mm. Em termos de composição do tecido enxertado, foi verificado que houve a presença de 15,66% de tecido ósseo, 28,83% de biomaterial e 55,49% de tecido mole. Dessa forma, concluiu-se que a utilização de blocos de osso bovino desproteinizado em cirurgias de elevação de seio maxilar foi eficiente no aumento da disponibilidade óssea, o que permitiu a instalação de implantes (AU).

The aim of this study was to evaluate, by means of tomographic and histological examination, the behavior of deproteinized bovine bone graft blocks in maxillary sinus floor elevation surgeries. The sample consisted of 7 female patients who requires the installation of osseointegrated implants for rehabilitation of the posterior or total edentulous maxilla, that presented pneumatization of the maxillary sinus with the need for vertical increase through grafting techniques. Patients underwent maxillary sinus floor elevation surgery and the sinus cavity was filled with a deproteinized bovine graft in the form of ablock that was kept fixed inside the maxillary sinus by means of a graft ixation screw. After 6 months of the surgical procedure, a tomographic evaluation was performed to evaluate the increase of the availability of bone tissue and histometric analysis of the biopsies to evaluate the composition of the repaired tissue. It was verified that there was an increase in the height of the alveolar ridge. Before the surgical procedure was 4.10 ± 2.03 mm and at the moment of the installation of the implants was 19.04 ± 2.45 mm. In terms of the composition of the grafted tissue, it was verified that 15.66% of bone tissue was present, 28.83% of biomaterial, and 55.49% of soft tissue. Thus, it can be concluded that the use of deproteinized bovine bone blocks in maxillary sinus surgeries was efficient in increasing the bone availability that allowed the implantation of implants (AU).

Evaluation of the bone anatomy of the anterior region of the mandible using cone beam computed tomography / Avaliação da anatomia da região anterior da mandíbula por meio de tomografia de feixe cônico

Background: Hemorrhages, mouth floor edema and tongue elevation are complications related to surgical procedures in the anterior region of the mandible. Objective: The objectives of this study were to evaluate the presence and location of the lingual foramen in the anterior region of the mandible and to evaluate mandibular morphology using cone beam computerized tomography (CBCT). Material and method: The mandible's morphology and the location, diameter and height of the lingual foramina were analyzed using the midline and the mental foramen as references, in 278 CBCT. Result: 88% of the sample had a midline lingual foramen, totaling 408 foramina, with a mean diameter of 0.93 mm. Foramina in the lingual region between the midline and mental foramina were detected in 75% of the sample, with a mean diameter of 0.807 mm. There was no positive correlation between the presence of lingual foramina in the lateral or in the midline regions (r = -0.149; p = 0.013). In the midline region, the type I mandibular shape was predominant (96%), and type III was predominant in the lateral regions. Conclusion: Considering the prevalence of these structures and their clinical relevance in potential surgical complications, it is important to carefully analyze the anterior region of the mandible during surgical planning.

Introdução: Hemorragias, edema no assoalho bucal e elevação da língua são complicações relacionadas a procedimentos cirúrgicos na região anterior da mandíbula. Objetivo: Os objetivos deste estudo foram avaliar a presença e localização do forame lingual na região anterior da mandíbula e avaliar a morfologia mandibular utilizando tomografia computadorizada com feixe de cone (CBCT). Material e método: A morfologia da mandíbula e a localização, diâmetro e altura do forame lingual foram analisados utilizando a medula e o forame mental como referências em 278 CBCT. Resultado: 88% da amostra tinha um forame lingual da linha média, totalizando 408 forames, com um diâmetro médio de 0,93 mm. Na região lingual entre a linha média e forames mentais foram detectados em 75% da amostra, com um diâmetro médio de 0,807 mm. Não houve correlação positiva entre a presença de forames lingual nas regiões lateral ou na região média (r = -0,149; p = 0,013). Na região da linha média, a forma mandibular do tipo I era predominante (96%) e o tipo III predominava nas regiões laterais. Conclusão: Considerando a prevalência dessas estruturas e sua relevância clínica em possíveis complicações cirúrgicas, é importante analisar cuidadosamente a região anterior da mandíbula durante o planejamento cirúrgico.