The present invention discloses a self-contained dental prophylaxis angle with a separate therapeutic content lumen and drive shaft lumen. The phrophylaxis angle also provides an offset rotational axis and methods for its use in cleaning, polishing, bleaching, bonding, etching, abrading, desensitizing, or otherwise treating teeth. An offset drive system is provided to power rotation of the dental tip in a system that can be physically separated from the storage and dispensing system for therapeutic content. A self-contained dental prophylaxis angle with an offset rotational axis according to the present invention may be used with a variety of shaped dental tips of varying degrees of rigidity, according the needs of a given clinical application.