Urban Bone Contouring Instrument Urban Bone Contouring Instrument CURBAN2 This instrument is intended to be used in crown lengthening procedures and may be used for tunneling or re-contouring the bone crest, especially in small regions of the mouth. Where to Buy x Category Dealer PartnersSales RepresentativeStrategic MarketsSchools RepresentativeAccutron™ Equipment Sales Zip Code Find RepresentativeReset Select a category, input a zip code and click on Find Representative, or explore the complete list here.