Binge-Like Exposure During Adolescence Induces Detrimental Effects in Alveolar Bone that Persist in Adulthood.

BACKGROUND: Alcohol (EtOH) intake during adolescence has become an important public health issue. Although the detrimental effects of EtOH intake on the musculoskeletal system are well known, only a few studies have investigated its impact on the stomatognathic system of adolescents. This study aimed to investigate the effect of EtOH binge drinking on the alveolar bone and the long-term consequences after abstinence. METHODS: Adolescent female Wistar rats (35 days old) were exposed to 4 cycles of EtOH binge drinking (3 g/kg/d; 3 days On-4 days Off) or distilled water (control group). Alveolar bone micromorphology and vertical bone distance were evaluated at 1, 30, and 60 days after that last EtOH intake through X-ray computed microtomography. The mineral:matrix ratio was assessed through Raman spectroscopy. RESULTS: A decrease in both trabecular thickness and volume ratio, and an increase in trabecular separation were observed at the 1-day evaluation (immediate withdrawal). After 30 and 60 days, the alveolar bone parameters were found similar to control, except for the mineral:matrix ratio in the long-term abstinence. CONCLUSIONS: EtOH binge drinking during adolescence results in alveolar bone damage that may persist in adulthood, even after abstinence.

Mandibular Osteonecrosis Associated With Raloxifene.

Osteonecrosis is a disease with diverse pathophysiology, clinical presentation, and management. It may be associated with some medications used to treat systemic issues with bone metabolism. A few cases of jaw bone osteonecrosis have been associated with raloxifene. In this paper, the authors present a clinical report of a 64-year-old woman who presented with a necrosis foci in the right alveolar ridge of the mandible, associated with continued raloxifene use.

Bisphosphonate-Related Osteonecrosis of the Jaw After Tooth Extraction.

Bisphosphonates are widely used for treatment or prevention of bone diseases characterized by high osteoclastic activity. Among the oral medicines used to treat osteoporosis, alendronate has been often used. Despite of the low rate of complications on its use, cases of osteonecrosis of the jaw have been reported on literature after tooth extractions. The main symptoms include pain, tooth mobility, swelling, erythema, and ulceration. The risk factors related to osteonecrosis of the jaw associated with bisphosphonate are exposition time to the medicine, routes of administration, and oral surgical procedures performed. The aim of this work is to report a case of a patient showing osteonecrosis of the jaw associated with the use of oral bisphosphonates after tooth extractions. The patient was treated through the suspension of the alendronate with the removal of the necrotic tissue and the foci of infection. After a year's follow-up, the patient showed no recurrence signs. From the foregoing, the interruption of the alendronate use and the surgical treatment associated to antibiotic therapy showed effective on the patient's treatment.

Mandibular bisphosphonate-related osteonecrosis after dental implant rehabilitation: a case report.

It has been a matter of debate as to whether dental implant therapies are suitable for patients subjected to long-term use of bisphosphonates (BPs). This report presents a case of a 76-year-old woman who developed BPs-related osteonecrosis of the jaw (BRONJ) in the left hemimandible after dental implant exposure. The implants and the necrotic crestal bone were removed, and postoperatively, a delay in tissue healing with bone exposure was noticed. The histologic analysis of the block biopsies revealed a lamellar bone tissue exhibiting necrotic areas and bacterial colonies associated with the bone outer surface. The bone-implant interface showed viable lamellar bone with enlarged vascular spaces in the areas between the implant threads. The possible mechanisms for the loss of implants in BRONJ patients are discussed, and the potential protocols for dental implant rehabilitation for patients under BP therapies are presented.

Osteonecrose mandibular associada ao uso de bifosfonato: relato de caso / Biphosphonate related osteonecrosis of the jaw: case report

Introdução: os bifosfonatos são um grupo de medicamentos utilizados no tratamento de doenças malignas metastáticas e em outras doenças ósseas como osteoporose e doença de Paget. Seu mecanismo de ação reduz a reabsorção óssea, a inibição do recrutamento e promoção da apoptose de osteoclastos. Apesar dos grandes benefícios para pacientes nestas condições, uma complicação associada ao seu uso é aosteonecrose dos maxilares. Objetivo: relatar um caso clínico envolvendo um paciente do sexo masculino de 72anos, sob tratamento endovenoso mensal com ácido zoledrônico, que evoluiu com osteonecrose espontânea bilateral em região posterior mandibular após um ano sob uso desta medicação. Conclusão: a conscientização dos Cirurgiões Dentistas quanto à etiologia da osteonecrosee a manutenção de ótima higiene oral nos pacientes sob uso destes medicamentos são fundamentais na prevenção da ocorrência desta condição.

Introduction: Biphosphonates are a group of drugs used to treat metástases associated with breast or prostate cancer and other bone diseases, including osteoporosis and Paget disease. They inhibit bone resorption through na action on osteoclasts slowing their activity and inducing apoptosis. Despite the benefits of biphosphonates, osteonecrosis of the jaw (ONJ) has emerged as a serious complication in some patients treated with these drugs. Aim: a case report of a 72-year-old male treated with zoledronic acid for one year that presented spontaneous bilateral ONJ is presented. Conclusion: the awareness of the dentists regarding the etiology of the ONJ and the maintenance of a great oral hygine by the patients under these medications are essencial for preventing this condition.

Intermittent therapy with 1,25 vitamin D and calcitonin prevents cyclosporin-induced alveolar bone loss in rats.

Bone loss associated with cyclosporin A (CsA) therapy can result in serious morbidity to patients. Intermittent administration of 1,25 Vitamin D and calcitonin reduces osteopenia in a murine model of postmenopausal osteoporosis. The purpose of this study was to evaluate the effects of this therapeutic approach on CsA-induced alveolar bone loss in rats. Forty male Wistar rats were allocated to four experimental groups according to the treatment received during 8 weeks: (1) CsA (10 mg/kg/day, s.c.); (2) 1,25 Vitamin D (2 microg/kg, p.o.; in weeks 1, 3, 5, and 7) plus calcitonin (2 microg/kg, i.p.; in weeks 2, 4, 6, and 8); (3) CsA concurrently with intermittent 1,25 Vitamin D and calcitonin administration; and (4) the control treatment group (vehicle). At the end of the 8-week treatment period, serum concentrations of bone-specific alkaline phosphatase, tartrate-resistant acid phosphatase (TRAP-5b), osteocalcin, interleukin (IL)-1 beta, IL-6, and tumor necrosis factor alpha (TNF-alpha) were measured and an analysis of bone volume, bone surface, number of osteoblasts, and osteoclasts was performed. CsA administration resulted in significant alveolar bone resorption, as assessed by a lower bone volume and an increased number of osteoclasts, and increased serum bone-specific alkaline phosphatase, TRAP-5b, IL-1 beta, IL-6, and TNF-alpha concentrations. The intermittent administration of calcitriol and calcitonin prevented the CsA-induced osteopenic changes and the increased serum concentrations of TRAP-5b and inflammatory cytokines. Intermittent calcitriol/calcitonin therapy prevents CsA-induced alveolar bone loss in rats and normalizes the production of associated inflammatory mediators.

Mandibular avascular osteonecrosis caused by bisphosphonate - a case report and brief review / Osteonecrose avascular de mandíbula por uso de bisfosfonato - relato de caso e breve revisão

Purpose: To present a case of total bilateral jaw necrosis in a patient with primary breast cancer and bone metastases treated with zeledronic acid and discuss the adverse effects of biphosphonates and the best moment to perform dental procedures. Case description: A female patient, 62 years old, with primary breast adenocarcinoma underwent chemotherapy and zoledronic acid because of bone metastases on the right hip. After 7 months, she was submitted to debridement of exposed bone on the anterior mandible, which resulted in skin fistulae and severe pain. Computerized tomography showed bone sequestration hypodensity at the right and left mandibular body and mentum with excessive uptake of the labeled drug as seen by bone scintigraphy. The patient received amoxicillin, gluconate and chlorhexidine mouthrinse and hydrogen peroxide; partial closure of skin fistulae was achieved. After 4 months, the patient returned with submandibular tissue necrosis, intra- and extra-orally exposed mandible with active discharge. After 5 days of palliative treatment, the patient died from sepsis. Conclusion: Local infection/inflammation should be treated before the use of biphosphonates, and topic and systemic pharmacologic treatment should be combined with a strict follow-up. For selected cases, the osteonecrosis treatment may include conservative debridement, pain control, topic and systemic antimicrobial control, and, in extremely severe cases, radical surgery.

Objetivo: Apresentar um caso de necrose total de mandíbula, bilateral, em uma paciente com neoplasia primária de mama e metástases ósseas tratadas com ácido zoledrônico endovenoso, e discutir os efeitos adversos de bisfosfonatos e o momento adequado para realização de procedimentos odontológicos. Descrição do caso: Paciente do sexo feminino, 62 anos, com adenocarcinoma de mama primário foi submetida a quimioterapia e uso de ácido zoledrônico devido a metástases ósseas no quadril direito. Após 7 meses, realizou-se debridamento de osso exposto na região anterior da mandíbula, resultando em fístulas e dor severa. Os exames de tomografia computadorizada e de cintilografia óssea revelaram hipodensidade do sequestro ósseo no corpo mandibular e no mento com presença excessiva da droga nestes sítios. Após antibioticoterapia e uso de enxaguatórios bucais houve fechamento parcial das fístulas. Após 4 meses, a paciente retornou com necrose submandibular e osso mandibular exposto intra e extraoralmente com drenagem. Após 5 dias de tratamento paliativo a paciente morreu de sepsis. Conclusão: Focos de infecção e/ou processos inflamatórios locais devem ser tratados previamente ao uso de bisfosfonatos. Indica-se o tratamento farmacológico tópico e sistêmico, e a proservação do caso. Terapias para osteonecrose, em determinados casos, envolvem debridamento conservador, controle da dor, manejo antimicrobiano tópico e sistêmico e, em casos extremos, cirurgia radical.

Osteonecrosis avascular maxilar: guías de prevención para pacientes tratados con bifosfonatos / Avascular necrosis of the jaw: prevention guidelines for patients with biphosphonates treatment

Los bifosfonatos conforman un grupo de medicamentos que se utilizan desde hace unos 30 años para resolver diferentes condiciones que afectan la calidad del hueso de soporte. El uso actual es masivo, por tiempos prolongados y los esquemas de dosis grandes e intermitentes, de productos de alta potencia anti-resortiva ósea se asocian con la aparición de nuevos eventos adversos como la osteonecrosis de mandíbula (ONM). La ONM es sin embargo poco frecuente, se ha visto en el 0,8 por ciento de los pacientes con cáncer y factores de riesgo, tratados con productos intravenosos, dosis altas por tiempos de 3 o más años. Este evento es casi anecdótico con los esquemas orales intermitentes, en pacientes con osteoporosis, e inexistente cuando se utilizan diariamente productos de potencia anti-resortiva ósea moderada, por la vía oral y períodos de hasta un año. Aquí se resumen algunas recomendaciones elementales para que el odontólogo identifique los casos con riesgo y prevenga la aparición eventual de ONM.

Low- and high-yield cigarette smoke inhalation potentiates bone loss during ligature-induced periodontitis.

BACKGROUND: It is well recognized that cigarette consumption is a strong risk factor for periodontitis. Tobacco companies have developed a cigarette with low levels of toxic compounds; however, its effect on periodontium has not been investigated. The aim of this study was to verify the impact of smoke produced by low- and high-yield cigarettes on bone loss resulting from ligature-induced periodontitis. METHODS: A total of 36 male Wistar rats were used in the study. A ligature was placed around one of the mandibular first molars (ligated teeth) of each animal, and they were assigned randomly to one of three groups: group 1: control (N = 10), group 2: 30 days' inhalation of smoke produced by high-yield cigarettes (N = 13), and group 3: 30 days' inhalation of smoke produced by low-yield cigarettes (N = 13). The animals were sacrificed 30 days after ligature placement, and the specimens were processed for decalcified sections. RESULTS: Intergroup analysis of unligated teeth (without periodontal disease) did not show a significant difference regarding periodontal ligament area (2.40 +/- 0.5 mm(2), 2.72 +/- 0.7 mm(2), and 2.61 +/- 0.4 mm(2) for groups 1, 2, and 3, respectively; P >0.05). Conversely, significant differences were noted in ligated teeth (with periodontitis); bone loss was directly proportional to the level of toxic compounds in the cigarettes (5.74 +/- 0.5 mm(2), 7.40 +/- 0.50 mm(2), and 6.51 +/- 0.50 mm(2) for groups 1, 2, and 3, respectively; P <0.05). CONCLUSION: Low- and high-yield cigarettes potentiated bone loss during experimental periodontitis in a directly proportional fashion.

Histologic evaluation of the effect of nicotine administration on bone regeneration: a study in dogs

O objetivo do presente estudo foi avaliar histometricamente a influência da nicotina sobre a regeneração óssea de defeitos criados cirurgicamente em rebordos alveolares edêntulos de cães. Defeitos ósseos foram criados cirurgicamente em um dos lados da mandíbula de dezesseis cães e foram deixados para que curassem espontanea-mente. Os animais foram aleatoriamente designados para um dos seguintes grupos: Grupo 1 - controle (n = 8) e Grupo 2 - administração subcutânea de nicotina (2 mg/kg) duas vezes ao dia durante 4 meses (n = 8). Os animais foram sacrificados, e secções semi-seriadas descalcificadas, obtidas. Os parâmetros histométricos avaliados foram altura, largura, área e densidade do tecido ósseo neoformado. A análise intergrupos (Mann-Whitney "rank sum test") demonstrou que a administração de nicotina não influenciou altura, largura e área de tecido ósseo neoformado (p > 0,05). Entretanto, a administração de nicotina influenciou significativamente a densidade do tecido ósseo neoformado (p < 0,001). Dentro dos limites do presente estudo, pode-se concluir que a nicotina pode afetar, mas não impedir a regeneração de defeitos ósseos criados cirurgicamente em mandíbulas edêntulas de cães.