ABSTRACT
OBJECTIVES: The purpose of this paper is to report the development of extensive, gingival eruption cyst formation in neonatal dogs during chronic administration of cyclosporine, which regressed after treatment ceased. MATERIALS AND METHODS: As part of an investigation of the efficacy of adenoviral-mediated gene therapy in a canine model of Duchenne Muscular Dystrophy (DMD), 26 Golden retriever pups were given intramuscular injections of adenoviral gene constructs (at 2-5 days old) either with (15 pups) or without (9 pups) concomitant immunosuppression using oral cyclosporine (from 1 to 3 days old). RESULTS: The daily administration of cyclosporine to Golden Retriever pups from 1 to 3 days of age resulted in the formation of eruption cysts over the incisors after approximately 3 weeks of treatment. The gingiva over the remaining teeth became swollen. However unlike the incisors, part of the crown erupted through the gingiva. Continuous treatment for 60-90 days was associated with persistence and expansion of the cysts over the incisor teeth. The cysts resolved within 1 month if cyclosporine administration was discontinued. Movement of incisors within the jaws was not appreciably affected when compared with age-matched controls. CONCLUSION: Chronic cyclosporine administration to neonatal dogs induces the formation of eruption cysts over the incisors, which is reversible once treatment is discontinued and does not affect intraosseous eruption.
