title: The effect of guidance elements on the rotation of cast crowns during cementation.
abstract: The effect of guidance elements on the rotation of crowns was analyzed. Resin molars were prepared with curved or horizontal preparation lines. Further groups were formed with a groove or one or two boxes. Teeth were duplicated eightfold; crowns were produced and cemented with a rotational torque of 0.5 Ncm. The width of the cement gap was measured at 11 reference points. Having either one or two guidance boxes had a significant centering effect. No differences were found between both types of preparation lines. The use of a proximal guidance box may be considered to reduce torsion of a single crown during cementation.
authors.affiliation: Department of Prosthetic Dentistry and Biomedical Materials Science, Hannover Medical School, Germany. Eisenburger.Michael@mh-hannover.de
authors.forename: Michael
authors.initials: M
authors.lastname: Eisenburger
authors.forename: Swantje
authors.initials: S
authors.lastname: Klug
mesh_terms: D002484:Cementation; D003442:Crowns; D003722:Dental Alloys / Q000737:chemistry; D017267:Dental Prosthesis Design; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008277:Magnesium Oxide / Q000737:chemistry; D008963:Molar; D010165:Palladium / Q000737:chemistry; D011076:Polycarboxylate Cement / Q000737:chemistry; D012399:Rotation; D013499:Surface Properties; D019231:Tooth Preparation, Prosthodontic / Q000379:methods*; D014093:Tooth, Artificial; D019415:Torque; D054159:Torsion, Mechanical; D015034:Zinc Oxide / Q000737:chemistry
chemical_list: D003722:Dental Alloys; D005899:Glass Ionomer Cements; D011076:Polycarboxylate Cement; D008277:Magnesium Oxide; D010165:Palladium; C040235:Ketac-cem; D015034:Zinc Oxide