. The science and practice of dental surgery. Fl.:, (id I. of the lower, resulting in wear of these cusps andsurfaces ; and also a sliding contact (from side toside) resulting in wear of the palatal aspects ofthe upper incisors and the lingual aspects ofthe lower. These latter effects become more 531 marked as the wear of the molars allows ofmore forcible contact between the upper andlower front teeth. It will be seen that while the stresses on themolars and premolars are bilateral (outwardsand uiwards in both upper and lower), and sotend to neutralize one another, the stresses onthe canines a
. The science and practice of dental surgery. Fl.:, (id I. of the lower, resulting in wear of these cusps andsurfaces ; and also a sliding contact (from side toside) resulting in wear of the palatal aspects ofthe upper incisors and the lingual aspects ofthe lower. These latter effects become more 531 marked as the wear of the molars allows ofmore forcible contact between the upper andlower front teeth. It will be seen that while the stresses on themolars and premolars are bilateral (outwardsand uiwards in both upper and lower), and sotend to neutralize one another, the stresses onthe canines and incisors are unilateral (out-wards in the upper and inwards in the lower. Fig. 605. teeth). Hence displacement of the premolarsand molars is rare in normal dentures, whiledisplacement of the front teeth may occur inany denture after wear or loss of the back teethhas allowed undue approximation of the will always be slight in a normal andcomplete denture, but is rendered much moreobvious under abnormal conditions to be sub-sequently dealt with. Fig. •iO(i. of tlie wear of teeth that ultimatelytakes place under the masticating stress innearly normal dentures is shown in— Fig. COS, 3 . , 53,; Fig. 605, jS ] and Fig. 606, Note that in the upper canines the stressesare such as to exert pressure from the medianline, and in the lower canines towards themedian line of the mouth. Attention has been drawn to the fact thatthe stability of the molar and premolar teeth inthe perfect arch is due to the lateral stressesupon them being alternately inward and out-ward in both upper and lower teeth, the forcesthus tending to neutralize each oth
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectdentistry, bookyear19
