Clinical Paper Dental Implants Is the intake of selective serotonin reuptake inhibitors associated with an increased risk of dental implant failure? B.R. Chrcanovic, J. Kisch, T. Albrektsson, A. Wennerberg: Is the intake of selective serotonin reuptake inhibitors associated with an increased risk of dental implant failure?. Int. J. Oral Maxillofac. Surg. 2017; 46: 782–788. ã 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. B. R. Chrcanovic 1 , J. Kisch 2 , T. Albrektsson 1,3 , A. Wennerberg 1 1 Department of Prosthodontics, Faculty of Odontology, Malmo ¨ University, Malmo ¨, Sweden; 2 Clinic for Prosthodontics, Centre of Dental Specialist Care, Malmo ¨, Sweden; 3 Department of Biomaterials, Gothenburg University, Go ¨ teborg, Sweden Abstract. The aim of this retrospective study was to investigate the association between the intake of selective serotonin reuptake inhibitors (SSRIs) and the risk of dental implant failure. Patients were included if they were taking SSRIs only and no other medication, did not present any other systemic condition or compromising habits (bruxism, smoking, snuff), and complied with the use of prophylactic antibiotics for implant surgery. The multivariate generalized estimating equation (GEE) method and multilevel mixed-effects parametric survival analysis were used to test the association between SSRI exposure (predictor variable) and the risk of implant failure (outcome variable), adjusting for several potential confounders (other variables). The total number of implants with information available and meeting the necessary eligibility criteria was 931 (35 failures). These were placed in 300 patients. The implant failure rate was 12.5% for SSRI users and 3.3% for non- users (P = 0.007). Kaplan–Meier analysis showed a statistically significant difference in the cumulative survival rate (P < 0.001). The multivariate GEE model did not show a statistically significant association between SSRI intake and implant failure (P = 0.530), nor did the multilevel model (P = 0.125). It is suggested that the intake of SSRIs may not be associated with an increased risk of dental implant failure. Key words: dental implant; implant failure; selective serotonin reuptake inhibitors; multi- variate generalized estimating equation analy- sis; multilevel mixed-effects parametric survival analysis. Accepted for publication 26 January 2017 Available online 20 February 2017 Nowadays dental implant placement is an effective and predictable treatment modal- ity for replacing missing teeth in both fully and partially edentulous patients. Never- theless, failures still happen despite high implant survival and success rates. 1 Sev- eral risk factors have been suggested to influence the failure of implants. Surgical conditions, radiotherapy, the oral micro- bial environment, parafunctional habits, and prosthetic variables are some of these factors. Systemic diseases and compromising risky habits may affect the oral tissues by increasing their suscep- tibility to other diseases or by interfering Int. J. Oral Maxillofac. Surg. 2017; 46: 782–788 http://dx.doi.org/10.1016/j.ijom.2017.01.016, available online at http://www.sciencedirect.com 0901-5027/060782 + 07 ã 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.