title: Mathematical derivation of the minimally acceptable all-porcelain margin angle.
abstract: There is limited research defining the minimally acceptable porcelain margin angle required to withstand the stresses incurred during seating a restoration. A mathematical model was derived to calculate this critical porcelain margin angle. The factors involved in margin fracture were determined to be the tensile strength of the porcelain, the axial reduction, the diameter of the tooth, the porcelain margin angle, and the seating force. As the seating force increases, the porcelain margin angle required to prevent failure also increases. Increasing either the axial reduction or the diameter of the tooth allowed the minimum porcelain margin angle to decrease.
authors.affiliation: US Army Medical Center, Ft. Campbell, KY, USA. Deborah.Dalvit2@se.amedd.army.mil
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Dalvit
authors.forename: R A
authors.initials: RA
authors.lastname: Jackson
authors.forename: M Chad
authors.initials: MC
authors.lastname: Hawkins
authors.forename: M Harry
authors.initials: MH
authors.lastname: Parker
mesh_terms: D001696:Biomechanical Phenomena; D003442:Crowns; D003737:Dental Cavity Preparation / Q000379:methods*; D003776:Dental Porcelain / Q000737:chemistry*; D006801:Humans; D008962:Models, Theoretical; D033081:Shear Strength; D013718:Tensile Strength
chemical_list: D003776:Dental Porcelain