Good Day All
any help with a full porc crown measurements on a premolar (upper and lower)! any help will be appreciated!
Here are the measurements --for those who need them- others stick to your own.
Amalgam class II on molar : Pulpal depth- 1.6 mm, gingival floor width 1.3 mm to 1.4 mm, exit angles 90, proximal clearance 0.4 to 0.5 mm, isthumus width atleast 1.0 mm.
Amalgam class II on premolar : Pulpal depth- 1.6 mm, gingival floor width 1.0 mm to 1.2 mm, exit angles 90, proximal clearance 0.4 to 0.5 mm, isthumus width atleast 1.0 mm.
PFM on # 8 /9 or 6/11: Occlusal reduction (as compared to adjacent teeth) 1.7 to 2.0 mm, occlusal clearance 1.0 mm, facial shoulder 1.0 to 1.2 mm, lingual chamfer 0.5 mm, height of lingual axial wall 1.0 to 1.5 mm. Width of incisal edge 1.0 mm, margins- 0.5 mm supragingival.
PFM on # 4/12 : occlusal clearance 1.3 mm to 1.5 mm non-functional cusps, 1.7mm- 1.85mm funtional cusp, facial shoulder 1.0 to 1.2 mm, lingual chamfer 0.5 mm, margins- 0.5 mm supragingival. bevel the facial cusp. (no sharp angles).
Full porcelain crowns: Margins- Shoulder all over, occlusal clearance 1.7 mm non-funtional cusps, 2.0 mm functional cusps.
Full gold crown on molar : Funtional cusp- 1.5 mm, non-functional cusp 1.2 mm, uniform chamfer, 0.5 mm supragingival.
Class III composite: clinically by extent of decay, for RT exam:
facio-linguo height 2.0 mm, mesio-distal 1.5 to 1.75 mm, depth 1. 6 mm, gingival clearance 0.5 mm, exit angle 90, 0.5 mm uniform bevel all-over except facial cavosurface.
make sure not to leave any undermined enamel.
MOD onlay (gold) on molar: occlusal as per full gold crown, gingival floor width 1.5 mm, flared walls of proximal boxes, offset as a shoulder on functional cusp, bevel all margins must have a 'draw'.
3/4 crown on molar: occlusal as per full gold crown, lingually tapered grooves, groove position-esthetically acceptable, offset on facial cusp, beveled margins, uniform flow, grroves must have draw with rest of the onlay prep.
....based on Fundamental of Fixed Prosthodontics by Shillingburg, and, Sturdevant's Art & Science of Operative Dentistry.
Good Luck! Everybody !!