The oral health appliance (10) includes a source of light (16) having a wavelength which is suitable for determination of oral health conditions, as well as treatment thereof. An assembly (16) in the appliance directs the light to selected dental regions of the mouth. A light receiver and sensor (16) receives reflected light from the dental regions, produces signal information therefrom and delivers the signal information to a processor (20), which determines the presence of oral health conditions, as well as determining the overall coverage of the mouth during a use of the appliance. The information from the processor is then sent to a display (24), identifying the presence of any oral health conditions and the location thereof, as well as information concerning those areas of the mouth which have been investigated during the use of the appliance and those which have not. The appliance includes a light system (34, 36, 38; 72, 74 76), a brushing system (64, 66, 68) and a fluid delivery system (94, 96, 98, 100) for treatment of any oral health condition identified.