Osteonecrose associada ao uso de bifosfonato oral e o risco da perda de implante / Bisphophonate jaw osteonecrosis and the risk of implant loss: a literature review

O uso de implantes dentários tem aumentado na população, existindo controvérsias na indicação em pessoas que usam bifosfonatos (BFs). Objetivos: este trabalho analisou possíveis indicações e contraindicações de implantes dentários em pacientes utilizando BFs orais. Material e Métodos: foi realizada busca na literatura com os termos “implante dentário”, “bifosfonato” e “osteonecrose” nas bases de dados eletrônicas Pubmed/Medline e Scielo. Incluiu-se literatura no período de 2003 a 2012 na língua inglesa, portuguesa e espanhola. Artigos não relacionando BF aos implantes dentários foram excluídos. Resultados: foram identificados 21 artigos, incluindo cartas ao leitor, monografia, guias práticos de conduta, revisões de literatura e artigos de pesquisa, tendo os artigos de pesquisa maior foco neste trabalho. Estes foram divididos da seguinte forma: ensaios clínicos randomizados (3), não randomizados (1), coorte (1), estudos observacionais (3) e relato de caso (1). Não se observou interferência na reabsorção óssea com uso de BF oral em modelos animais, porém, em humanos, nove implantes dentários perdidos foram relatados (sete em dois estudos transversais, dois em um relato de caso). Conclusão: 1) a osteonecrose associada ao BF é originada pelo efeito cumulativo no organismo, tempo de utilização da droga, presença de outra doença dental associada e procedimentos invasivos; 2) BFs orais apresentam menos complicações do que endovenosos; 3) não se indica instalação do implante dentário sem avaliar o risco-benefício, considerando tempo de uso do BF oral e condições clínicas; 4) os protocolos recomendados por associações certificadas devem ser adotados

The use of dental implants has increased in the general population with controversies on its use for patients under bisphosphonate therapy (BF). Objectives: to analyze possible indications and implications of dental implant placement in patients under oral BFs. Material and Methods: a literature search was made with the terms “dental implant”, “bisphosphonate”, and “osteonecrosis” at PubMed/MEDLINE and Scielo electronic records. Portuguese, English, and Spanish literatures were screened from 2003 to 2012. Articles not relating BFs to dental implants were excluded. Results: 21 articles were identified, including letters to the editor, monographs, practical guidelines, literature reviews, and research articles, being the latter received more attention and divided into: randomized clinical trials (3), non-randomized trials (1), cohort (1), observational (3), and case report studies. In the animal model, BFs did not interfere with bone remodeling. However, nine dental implants were lost in human beings (7 in transversal studies, 2 in a case report). Conclusion: 1) BF osteonecrosis occurs do its cumulative effect in the organism, time of use, associated dental disease, and invasive procedures; 2) oral BFs present less complications than IV BFs; 3) implant placement must consider cost-benefit ratio, oral BF time period, and clinical conditions; and 4) recommended protocols of certified associations must be followed.

Oral Bisphosphonates Induced Osteonecrosis of the Mandible : a Case Report

Bisphosphonates have been approved for Paget's disease, cancer - related hypercalcemia, bone involvement in multiple myeloma or solid tumors and osteoporosis. Although, underlying pathophysiological mechanisms remain unclear, it seems that bisphosphonates inhibit osteoclast precursor cells, modulate migratory and adhesive characteristics and induce apoptosis of osteoclasts. Furthermore impacts on angiogenesis, microenvironment and signal transduction between osteoclasts and osteoblasts. In this report, we present a case of oral bisphosphonates induced osteonecrosis of the mandible in a 84-year-old patient who received for two years. Two tapered screw vent implants(Zimmer, USA) were placed in the area of first and second molar. Two weeks later after crowns restored, some inflammatory signs and symptoms were observed on the second molar area. Sequestrum was formed and the sequestrum was removed with the implant. Frequent follow-up checks and oral hygiene maintenances were done and the first molar implant was restored. There is insufficient evidence suggests that duration of oral bisphosphonate therapy correlates with the development and severity of osteonecrosis. Therefore, dentists should not overlook the possibility of development of bisphosphonate induced osteonecrosis in patients who have taken oral forms of medication for less than three years.