. Dental mthe cavity across the incisal end of the tooth, stopping well infront of, or just beyond, the second developmental groove.(Fig. 31). If the tooth is of normal thickness or less at the in-cisal end, both the labial and lingual plates of enamel should THE DENTAL SUMMARY 13 be cut away until dentin is reached, the lingual plate being cutmore deeply than the labial. A square^ shallow groove shouldbe made in this dentin, with a depression at the end, alsosquare in shape, with a slight undercut at its farthest point.(Fig. 32). If the tooth is of more than normal thickness at thei
. Dental mthe cavity across the incisal end of the tooth, stopping well infront of, or just beyond, the second developmental groove.(Fig. 31). If the tooth is of normal thickness or less at the in-cisal end, both the labial and lingual plates of enamel should THE DENTAL SUMMARY 13 be cut away until dentin is reached, the lingual plate being cutmore deeply than the labial. A square^ shallow groove shouldbe made in this dentin, with a depression at the end, alsosquare in shape, with a slight undercut at its farthest point.(Fig. 32). If the tooth is of more than normal thickness at theincisal end, the labial plate of enamel may be left and the lin-gual plate and half the dentin cut away to make the step. Theincisal end of the labial plate of enamel should be beveled andthe gold brought completely over it to protect it. In these cavities incisal anchorage should never be madeby cutting a pit in the dentin between the labial and lingualplates of enamel, as such anchorage must necessarily be Fie. 27 Fie. 28 Fie. 29 Fie. 30 It weakens the incisal end of the tooth by taking away thesupporting dentin and brings the joint between the tooth andthe filling, where the leverage employed has the greatest ten-dency to dislodge the filling. CAVITIES IN THE BICUSPIDS AND MOLARS INVOLVING THEPROXIMAL AND OCCLUSAL SURFACES. Cavities on the proximal surfaces of bicuspids and molarsshould always be made proximo-occlusal cavities when theproximating tooth is in position, for this reason: If the occlu-sal margin of a proximal cavity is extended to a self-cleansingsurface, the enamel will either be broken away by the pluggeror during mastication, or if the enamel is protected the fillingmaterial will be too thin to have good edge strength. (). If this margin is not brought to a self-cleansing surface,there will be a recurrence of decay if there is a condition of 11 THE DENTAL SUMMARY susceptibility in the mouth. These cavities have long been thebugbear of the averag
Size: 2600px × 961px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookiddent, booksubjectdentistry
