Introduction: Oral transmucosal fentanyl citrate (OTFC) (Actiq®) is specifically indicated for the management of breakthrough cancer pain. Our experience in a chronic pain rehabilitation program is that OTFC is also used for various chronic (non-cancer) pain syndromes. Several studies have utilized OTFC for breakthrough pain, but no trials have been conducted utilizing regular dosing of OTFC treatment of chronic pain.^1,2,3 Additionally, guidelines for use of opioids for chronic non-cancer pain do not specifically address the use of OTFC. Frequent consumption of sugar-containing products increases the risk of dental disease. Each unit of OTFC contains two grams of hydrated dextrates. A thorough literature review has failed to identify studies drawing a correlation between dental disease and OTFC. However, the product labeling for Actiq® lists dental disease among the adverse effects in the post-marketing experience section.⁴ Materials and Methods: We enrolled a 48 year old male with chronic generalized pain of eight years duration in our rehabilitation program. He had been treated with OTFC for more than three years and during this time developed extensive dental caries, decay, and tooth loss. He was first prescribed OTFC (400 mcg PRN) in November 2002. Dosing increased through June 2004 to a maximum of 600 mcg QID. Patient reports annual dental prophylaxis and minimal carious history. Prior dental records were not available for review. A dental examination in March 2004 identified multiple infected, non-restorable teeth. By June 2004 he had undergone extraction of eleven teeth. In May 2005 extraction of all remaining teeth was recommended. Results/Conclusions: We propose that the hydrated dextrates contained in OTFC were causally related to his advanced dental disease. Further studies are warranted to evaluate the putative correlation between the use of OTFC in the treatment of chronic pain and dental disease.