A device for treating a dental tissue comprising (a) an ozone generator for generating an ozone containing gas, (b) a first pump in fluid flow communication with the ozone generator for generating a flow of ozone containing gas, (c) an applicator for multiple teeth having a surface suitable for forming with the hard and soft dental tissue of multiple teeth to be treated (d) a treatment chamber having an inlet orifice in fluid flow communication with the ozone generator and the first pump and having an outlet orifice, and (e) a second pump in fluid flow communication with the outlet orifice of the applicator for removing gas from the treatment chamber. The second pump has a second throughput and the first pump has a first throughput whereby the ratio of the second throughput to the first throughput is at least 1.5:1.
