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BACKGROUND: Menopause induces oral bone loss, leading to various oral diseases. Mastication importantly affects bone metabolism in the jawbone. OBJECTIVE: To analyze the effect of enhanced masticatory force on osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), and mechano-growth factor (MGF) in alveolar bone of ovariectomized rats and to study the mechanics mechanism of the alveolar bone of ovariectomized rats response to enhanced masticatory force. METHODOLOGY: Thirty Sprague Dawley rats were randomly divided into three groups: sham-operation group (fat around the removed ovary + normal hard diet), model group (ovariectomy + normal hard diet), and experimental group (ovariectomy + high hard diet). It was a 2-month experiment. Enzyme-linked immunosorbent assay (ELISA) detected serum estradiol (E2), osteocalcin (BGP) and alkaline phosphatase (ALP) in rats. Bone histomorphometric indices in the third molar region of maxilla were detected by micro-CT; protein expressions of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Western blot; and gene expression of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Quantitative Real-Time PCR. RESULTS: Comparing with model group, serum E2 in experimental group increased but not significantly, serum BGP and serum ALP in experimental group decreased but not significantly, OPG in experimental group in alveolar bone increased significantly, RANKL in experimental group in alveolar bone decreased significantly, RANKL/OPG ratio in experimental group decreased significantly, MGF in experimental group in alveolar bone increased significantly, bone volume to total volume fraction increased significantly in experimental group, trabecular thickness increased significantly in experimental group, and trabecular separation decreased significantly in experimental group. CONCLUSION: Enhanced masticatory force affected the expression of OPG, RANKL, and MGF in alveolar bone of ovariectomized rats, improved the quality of jaw bone of ovariectomized rats, and delayed oral bone loss by ovariectomy.

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Abstract Menopause induces oral bone loss, leading to various oral diseases. Mastication importantly affects bone metabolism in the jawbone. Objective: To analyze the effect of enhanced masticatory force on osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), and mechano-growth factor (MGF) in alveolar bone of ovariectomized rats and to study the mechanics mechanism of the alveolar bone of ovariectomized rats response to enhanced masticatory force. Methodology: Thirty Sprague Dawley rats were randomly divided into three groups: sham-operation group (fat around the removed ovary + normal hard diet), model group (ovariectomy + normal hard diet), and experimental group (ovariectomy + high hard diet). It was a 2-month experiment. Enzyme-linked immunosorbent assay (ELISA) detected serum estradiol (E2), osteocalcin (BGP) and alkaline phosphatase (ALP) in rats. Bone histomorphometric indices in the third molar region of maxilla were detected by micro-CT; protein expressions of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Western blot; and gene expression of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Quantitative Real-Time PCR. Results: Comparing with model group, serum E2 in experimental group increased but not significantly, serum BGP and serum ALP in experimental group decreased but not significantly, OPG in experimental group in alveolar bone increased significantly, RANKL in experimental group in alveolar bone decreased significantly, RANKL/OPG ratio in experimental group decreased significantly, MGF in experimental group in alveolar bone increased significantly, bone volume to total volume fraction increased significantly in experimental group, trabecular thickness increased significantly in experimental group, and trabecular separation decreased significantly in experimental group. Conclusion: Enhanced masticatory force affected the expression of OPG, RANKL, and MGF in alveolar bone of ovariectomized rats, improved the quality of jaw bone of ovariectomized rats, and delayed oral bone loss by ovariectomy.

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OBJECTIVES: Hypertension is one of the main causes of premature death in the world; also, it is associated with several bone alterations. Preclinical studies have demonstrated delayed alveolar bone healing in hypertensive rats. However, losartan has been favorable for consolidation of bone grafts and reduction in active periodontitis. Therefore, losartan is suggested to be effective in bone formation stages, as well as in the synthesis of matrix proteins and mineralization. To evaluate the alveolar bone dynamics in hypertensive rats treated with losartan by laser confocal microscopy and histological analysis. METHODOLOGY: Thirty-two rats, 16 spontaneously hypertensive rats (SHR) and 16 Wistar albinus rats, treated or not with losartan (30 mg/kg/day) were used. Calcein fluorochrome at 21 days and alizarin red fluorochrome at 49 days were injected in rats (both 20 mg/kg). The animals were submitted to euthanasia 67 days after treatment, and then the right maxilla was removed for laser confocal microscopy analysis and the left maxilla for histological analysis. RESULTS: This study showed a greater calcium marking in normotensive animals treated with losartan in relation to the other groups. Laser confocal microscopy parameters showed higher values of bone volume formed, mineralized surface, active surface of mineralization and bone formation rate in normotensive animals treated with losartan. However, a smaller mineralized surface was observed in all hypertensive animals. CONCLUSION: Losartan can improve bone mineralization parameters under normal physiological conditions, but the same anabolic effect does not occur under hypertension.

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Objetivo: demonstrar, por meio de uma revisão de literatura, a utilização do hormônio do crescimento (GH) e concentrados plaquetários e sugerir técnica de associação de uso para odontologia em processos de preservação de osso alveolar. Revisão de literatura: enxertos ósseos são uma necessidade na área da saúde, por diversas razões. A utilização de osso autógeno apresenta grande desvantagem em ter um segundo sítio cirúrgico, entretanto, os substitutos ósseos não possuem as características ideais. Assim, existe a busca por alternativas que otimizem a cicatrização e a incorporação dos substitutos ósseos, dentre elas os concentrados sanguíneos, ricos em fatores de crescimento derivados das plaquetas e o hormônio do crescimento. É possível encontrar uma vasta literatura utilizando os concentrados sanguíneos, inclusive utilizando esses como veículos para outras substâncias. Os concentrados sanguíneos são ricos em fatores de crescimento derivados das plaquetas, como fator de crescimento semelhante à insulina (IGF), Fator de crescimento derivado de plaquetas (PDGF) e outros. Além disso, também é possível encontrar, na literatura, o uso tópico de hormônio do crescimento em enxertos ósseos, fraturas e implantes dentários. Entretanto, o GH possui uma meia-vida de 20 minutos, assim, quando utilizado em conjunto com a I-PRF, espera-se um aumento no tempo de ação local. Considerações finais: é possível otimizar os enxertos ósseos utilizando-se L-PRF/I-PRF e hormônio do crescimento. Porém, são necessárias mais pesquisas.(AU)

Objective: this study aims to show through a literature review the use of the growth hormone and platelet concentrates and to suggest an association technique for dentistry use in alveolar bone preservation processes. Literature review: bone grafts are a health requirement for a number of reasons. The use of autogenous bone has the main disadvantage of a second surgical site, while bone substitutes do not present optimal characteristics. Thus, there is a search for alternatives that optimize the healing and incorporation of bone substitutes, which include blood concentrates that are rich in platelet-derived growth factors and the growth hormone. A vast literature can be found on blood concentrates, including their use as vehicles to other substances. Blood concentrates are rich in platelet-derived growth factors such as IGF, PDGF, and others. Moreover, the literature also shows the topical use of the growth hormone in bone grafts, fractures, and dental implants. However, the growth hormone presents a half-life of 20 minutes; therefore, when combined with I-PRF, an increased time in local action is expected. Final considerations: it is possible to optimize bone grafts by using L-PRF/I-PRF and the growth hormone. However, further research is required.(AU)

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Abstract Hypertension is one of the main causes of premature death in the world; also, it is associated with several bone alterations. Preclinical studies have demonstrated delayed alveolar bone healing in hypertensive rats. However, losartan has been favorable for consolidation of bone grafts and reduction in active periodontitis. Therefore, losartan is suggested to be effective in bone formation stages, as well as in the synthesis of matrix proteins and mineralization. Objectives: To evaluate the alveolar bone dynamics in hypertensive rats treated with losartan by laser confocal microscopy and histological analysis. Methodology: Thirty-two rats, 16 spontaneously hypertensive rats (SHR) and 16 Wistar albinus rats, treated or not with losartan (30 mg/kg/day) were used. Calcein fluorochrome at 21 days and alizarin red fluorochrome at 49 days were injected in rats (both 20 mg/kg). The animals were submitted to euthanasia 67 days after treatment, and then the right maxilla was removed for laser confocal microscopy analysis and the left maxilla for histological analysis. Results: This study showed a greater calcium marking in normotensive animals treated with losartan in relation to the other groups. Laser confocal microscopy parameters showed higher values of bone volume formed, mineralized surface, active surface of mineralization and bone formation rate in normotensive animals treated with losartan. However, a smaller mineralized surface was observed in all hypertensive animals. Conclusion: Losartan can improve bone mineralization parameters under normal physiological conditions, but the same anabolic effect does not occur under hypertension.

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A pesar de los avances en la tecnología para preservar la dentición, aún se requiere la rehabilitación del sistema masticatorio en pacientes desdentados parcial o totalmente, lo que resulta difícil y frustrante -- tanto para los afectados como para los protesistas -- si existe atrofia grave del hueso alveolar. Este problema se puede solucionar mediante una intervención quirúrgica denominada profundización del vestíbulo, dirigida a lograr el aumento de la cresta alveolar y, con ello, el soporte de las prótesis dentales. A tal efecto, en el presente trabajo se propone y describe una nueva opción terapéutica: la técnica de Alemán y Pico, para la profundización del surco vestibular inferior, la cual no es tan invasiva y resulta factible cuando no se cuenta con las condiciones necesarias para colocar implantes, ya sea por escasez de recursos materiales o por situaciones propias del paciente

In spite of the advances in technology to preserve the eruption of teeth, the rehabilitation of the masticatory system is still required in partial or totally toothless patients, what is difficult and frustrating -- either for those affected patients or for the prosthesists -- if serious atrophy of the alveolar bone exists. This problem can be solved by means of a surgical procedure denominated deepening of the vestibule directed to achieve the increase of the alveolar crest and, with it, the support of the dental prosthesis. To such an effect, this work intends and describes a new therapeutic option: the Alemán and Pico technique, for deepening of the inferior vestibular edge, which is not so invasive and it is feasible when the necessary conditions to place an implant are not available, either due to shortage of material resources or due to situations of the patients themselves

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O tecido adiposo pode regular o metabolismo ósseo e estar envolvido na fisiopatologia da osteoporose, sendo este fator determinante no sucesso de tratamentos reabilitadores com implantes dentários osseointegrados. O presente estudo de coorte prospectivo teve como objetivo verificar o padrão ósseo alveolar por meio de índices radiomorfométricos da radiografia panorâmica e medidas lineares realizadas em radiografias periapicais, em pacientes eutróficas e obesas mórbidas antes e após a cirurgia bariátrica. A amostra foi constituída por 31 mulheres com idade de 20 a 35 anos, sendo divididas em 2 grupos: Grupo Experimental (GE-Obesas de Grau III, IMC >40 Kg/m2) e Grupo Controle (GC- Eutróficas, IMC 18,5 a 24,99 Kg/m2). Foram avaliadas 20 eutróficas e 11 obesas mórbidas no pré e pós-cirurgia bariátrica (6 meses). Índices radiomorfométricos e de placa dentária foram avaliados nos tempos T0 (baseline) e T1 (6 meses). Na análise radiográfica foram avaliados o padrão trabecular através da escada visual de Lindh e a perda óssea por meio do cálculo da distância da junção cemento-esmalte à crista óssea, em radiografias periapicais. Já as radiografias panorâmicas para mensurar Índice da Cortical Mandibular (ICM), Índice Mentoniano (IM) e Índice Panorâmico Mandibular (IPM), além do índice de Placa de Turesky. Houve perda óssea significativa em T1 nas pacientes submetidas à cirurgia bariátrica, quando comparada com as eutróficas (p<0,05). O padrão trabecular tornou-se mais esparso após a cirurgia apresentando uma diferença visual. No índice de placa foi observada uma ligeira melhora após a cirurgia e os eutroficos mantiveram valores similares ao longo do tempo. Pode-se concluir que pacientes obesas apresentam maior perda óssea, a qual piora após a cirurgia bariátrica, quando comparada com o de pacientes eutróficas. O mesmo acontecendo com o trabeculado ósseo que se torna mais esparso após a cirurgia bariátrica.(AU)

Adipose tissue can regulate bone metabolism and be involved in the pathophysiology of osteoporosis, being this determinant factor in the success of rehabilitative treatments with osseointegrated dental implants. The present prospective cohort study aimed to verify the alveolar bone pattern through radiomorphometric indices of panoramic radiography and linear measurements performed in periapical radiographs in eutrophic and morbidly obese patients before and after bariatric surgery. The sample consisted of 31 women aged 20-35 years old, divided into 2 groups: Experimental Group (GE-Obesas de Grade III, BMI> 40 Kg / m2) and Control Group (GC-Eutrophic, BMI 18.5 To 24.99 kg / m2). 20 eutrophic and 11 obese morbidities were evaluated in the pre and postoperative bariatric surgery (6 months). Radiomorphometric and plaque indices were evaluated at T0 (baseline) and T1 (6 months) times. In the radiographic analysis the trabecular pattern through the Lindh visual ladder and the bone loss were evaluated by calculating the distance from the cemento-enamel junction to the bone crest in periapical radiographs. Panoramic radiographs were used to measure the Mandibular Cortical Index (ICM), Mentonian Index (IM) and Panoramic Mandibular Index (MPI), in addition to the Turesky Plate index. There was a significant loss of bone in T1 in patients submitted to bariatric surgery, when compared to eutrophic patients (p <0.05). The trabecular pattern became more sparse after surgery with a visual difference. The plate index showed a slight improvement after surgery and the eutrophic maintained similar values over time. It can be concluded that obese patients present greater bone loss, which worsens after bariatric surgery, when compared to that of eutrophic patients. The same happens with the trabecular bone that becomes more sparse after bariatric surgery.(AU)

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AIM: To evaluate the influence of gingival thickness and bone grafting on buccal bone plate remodelling after immediate implant placement in sockets with thin buccal bone, using a flapless approach. MATERIALS AND METHODS: The gingiva of eight dogs was thinned at one side of the mandible, mandibular premolars were extracted without flaps, and four implants were installed on each side at 1.5 mm from the buccal bone. The sites were randomly assigned into: TG (test group) = thin gingiva; TG + GM (TG with grafting material); CG (control group) = normal gingiva; and CG + GM (CG with grafting material). After 12 weeks the dogs were sacrificed and the samples were processed for histological analysis. RESULTS: All animals exhibited a thin buccal bone initially. In all the experimental groups the buccal gap was filled with newly formed bone and the buccal bone level was slightly apical to the implant shoulder. There were no statistically significant differences among the groups for the histomorphometric parameters. CONCLUSIONS: The thickness of the buccal bone was a fundamental factor in buccal bone plate resorption, even with flapless implantation. The gingival thickness or the addition of a biomaterial in the gap did not influence the results.

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The aim of this study was to analyze the effect of the separation of prosthetic crowns from fixed partial dentures by means of stress gradient evaluation. Three photoelastic models were created to examine contiguous implants with varying contact between the crowns (contact point [CP], contact surface [CS], splinted [SP]). The SP group presented the best results, followed by the CS group, indicating that the use of splinted prosthetic crowns and crowns with broad surface contacts is viable when considering the stress values.

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