Dental Extractions in Patients Receiving Bisphosphonate Therapy

Abstract

In their recent article, Lodi et al 1 Lodi G. Sardella A. Salis A. et al. Tooth extraction in patients taking intravenous bisphosphonates: A preventive protocol and case series. J Oral Maxillofac Surg. 2010; 68: 107 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar proposed a protocol for the prevention of osteonecrosis of the jaws (ONJ) in patients receiving intravenous (IV) bisphosphonates (BP). The authors provided sufficient follow-up data to document null incidence of ONJ in 23 patients receiving IV BP following their extraction protocol. Importantly, the risk for ONJ in patients receiving IV BP following routinely performed dental extractions has been reported to range from 16-fold 2 Kyrgidis A. Vahtsevanos K. Koloutsos G. et al. Bisphosphonate related osteonecrosis of the jaws: Risk factors in breast cancer patients A case-control study. J Clin Oncol. 2008; 26: 4634 Crossref PubMed Scopus (155) Google Scholar to 53-fold. 3 Hoff A.O. Toth B.B. Altundag K. et al. Frequency and risk factors associated with osteonecrosis of the jaw in cancer patients treated with intravenous bisphosphonates. J Bone Miner Res. 2008; 23: 826 Crossref PubMed Scopus (507) Google Scholar The authors note that one cannot know the exact proportion of dental extractions performed on at-risk subjects that result in osteonecrotic lesions. 1 Lodi G. Sardella A. Salis A. et al. Tooth extraction in patients taking intravenous bisphosphonates: A preventive protocol and case series. J Oral Maxillofac Surg. 2010; 68: 107 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar In this regard, we have recently published a longitudinal cohort study in cancer patients receiving IV BP. 4 Vahtsevanos K. Kyrgidis A. Verrou E. et al. Longitudinal cohort study of risk factors in cancer patients of bisphosphonate-related osteonecrosis of the jaw. J Clin Oncol. 2009; 27: 5356 Crossref PubMed Scopus (323) Google Scholar From the raw data of the latter study, it is possible to calculate the proportion noted by Lodi et al. Table 1 presents this information for the first time. In our cohort, 114 patients were subjected to dental extractions, which were routinely performed in private-practice settings in northern Greece. None of the patients had been diagnosed with ONJ at the time of dental extraction. There were 87 women and 27 men, with a mean age of 61.7 years (range 39-92 years). Prescription indication for IV BP were multiple myeloma (49 patients), metastatic breast cancer (63 patients), and metastatic prostate cancer (2 patients). BP treatment was zoledronate (71 patients), zoledronate followed by ibandronate (14 patients), pamidronate (17 patients), and pamidronate followed by zoledronate (12 patients). Of these 114 patients, 46 (40.4%) had a subsequent confirmed diagnosis of ONJ in a mean follow-up of 20.4 months (range 5-68 months). Thus, the proportion noted by Lodi et al is available to the readers of the journal (bold text in Table 1). A hypothetical comparison of the 2 cohorts, which had similar follow-up duration and dosing schemas, 1 Lodi G. Sardella A. Salis A. et al. Tooth extraction in patients taking intravenous bisphosphonates: A preventive protocol and case series. J Oral Maxillofac Surg. 2010; 68: 107 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar , 4 Vahtsevanos K. Kyrgidis A. Verrou E. et al. Longitudinal cohort study of risk factors in cancer patients of bisphosphonate-related osteonecrosis of the jaw. J Clin Oncol. 2009; 27: 5356 Crossref PubMed Scopus (323) Google Scholar is presented in Table 2. From the amalgamation of these data, it is clear that the protocol proposed by Lodi et al demonstrates substantial efficacy. Table 1Dental Extractions Performed in a Cohort of Multiple Myeloma, Breast, and Prostate Cancer Patients Treated with Intravenous Zoledronate, Pamidronate, and Ibandronate from Theagenio Cancer Hospital (n = 1621) ONJ Total No Yes Dental extraction No n 1,473 34 1,507 % within extraction 97.7 2.3 100.0 Yes n 68 46 114 % within extraction 59.6 40.4 100.0 Total n 1,541 80 1,621 % within extraction 95.1 4.9 100.0 Abbreviation: ONJ, osteonecrosis of the jaw. Pearson χ2 for dental extraction comparison, P < .001. Descriptive and analytical statistics describing the cohort have been published previously. 4 Vahtsevanos K. Kyrgidis A. Verrou E. et al. Longitudinal cohort study of risk factors in cancer patients of bisphosphonate-related osteonecrosis of the jaw. J Clin Oncol. 2009; 27: 5356 Crossref PubMed Scopus (323) Google Scholar Open table in a new tab Table 2Hypothetical Comparison of Cohorts ONJ Total No Yes Cohort Thessaloniki n 68 46 114 % within cohort 59.6 40.4 100.0 Milan n 23 0 23 % within cohort 100.0 0.0 100.0 Total n 91 46 137 % within city 66.4 33.6 100.0 Abbreviation: ONJ, osteonecrosis of the jaw. Pearson χ2 for cohort comparison, P < .001. Thessaloniki, Greece, cohort (Theagenio Cancer Hospital): 114 cancer patients receiving intravenous bisphosphonates in whom dental extractions were performed in private-practice settings. Milan, Italy cohort (Universitá degli Studi di Milano): 23 patients receiving intravenous bisphosphonates in whom dental extractions were performed according to the study protocol of Lodi et al at a university dental clinic. 1 Lodi G. Sardella A. Salis A. et al. Tooth extraction in patients taking intravenous bisphosphonates: A preventive protocol and case series. J Oral Maxillofac Surg. 2010; 68: 107 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar Open table in a new tab Abbreviation: ONJ, osteonecrosis of the jaw. Pearson χ2 for dental extraction comparison, P < .001. Descriptive and analytical statistics describing the cohort have been published previously. 4 Vahtsevanos K. Kyrgidis A. Verrou E. et al. Longitudinal cohort study of risk factors in cancer patients of bisphosphonate-related osteonecrosis of the jaw. J Clin Oncol. 2009; 27: 5356 Crossref PubMed Scopus (323) Google Scholar Abbreviation: ONJ, osteonecrosis of the jaw. Pearson χ2 for cohort comparison, P < .001. Thessaloniki, Greece, cohort (Theagenio Cancer Hospital): 114 cancer patients receiving intravenous bisphosphonates in whom dental extractions were performed in private-practice settings. Milan, Italy cohort (Universitá degli Studi di Milano): 23 patients receiving intravenous bisphosphonates in whom dental extractions were performed according to the study protocol of Lodi et al at a university dental clinic. 1 Lodi G. Sardella A. Salis A. et al. Tooth extraction in patients taking intravenous bisphosphonates: A preventive protocol and case series. J Oral Maxillofac Surg. 2010; 68: 107 Abstract Full Text Full Text PDF PubMed Scopus (77) Google Scholar In replyJournal of Oral and Maxillofacial SurgeryVol. 68Issue 7PreviewIn their comment on our article published in the Journal of Oral and Maxillofacial Surgery (J Oral Maxillofac Surg 68:107, 2010), Kyrgidis et al made some useful observations on important aspects of osteonecrosis of the jaw (ONJ) in patients receiving intravenous bisphosphonates (BP). In particular, using raw data from one of their studies, they suggest putative incidence of ONJ following dental extraction in the absence of preventive treatment to be greater than 40%. Kyrgidis et al state that the risk of ONJ in such patients can be up to 53-fold greater; however, we think that reliable figures will not be available until studies specifically aimed at this subject determine incidence rates from prospective follow-up of patients who receive intravenous BP and undergo tooth extraction. Full-Text PDF