Verhandlungen des XInternationalen medicinischen congresses, Berlin, 1890 . makes the bite too close in these cases. Notwithstanding thiswhen the palatal surfaces of the upper central incisors are normal inoutline, the lower incisors are prevented from sliding back against thepalate by coming in contact with the basilar surfaces, but when thesesurfaces are not sufficiently curved, the lower incisors have a tendencyto glide backwards toward the palate and finally find a resting placein the alveolar process. The irritation which results from the pressureagainst the mucous membrane pro
Verhandlungen des XInternationalen medicinischen congresses, Berlin, 1890 . makes the bite too close in these cases. Notwithstanding thiswhen the palatal surfaces of the upper central incisors are normal inoutline, the lower incisors are prevented from sliding back against thepalate by coming in contact with the basilar surfaces, but when thesesurfaces are not sufficiently curved, the lower incisors have a tendencyto glide backwards toward the palate and finally find a resting placein the alveolar process. The irritation which results from the pressureagainst the mucous membrane produces excessive deposit of bonecellsin the inner plate of the alveolar process which causes the superiorcentral incisors to be carried forward. This irritation is intensified by the masticating process, and theincisors, being deprived of their natural function, flare out. As thecentral incisors begin to protrude, the laterals also become affectedand finally the cuspids. The cutting edges of the teeth appear belowthe upper lip and the lower lip is caught beneath, increasing the ten-. Fig. 2. dency to stand out. The more the orbicularis oris is deprived of itsfunctions, the greater the tendency of the upper teeth to project. Themarked influence of the upper lip in keeping the teeth in position isshown in the case of the upper incisors that turn inward in excessivelydeveloped upper maxillae. From want of proper occlusion, the loweralveolar process becomes abnormally developed as the teeth are car-ried up against it. The extent of the anterior movement depends upon the height ofthe vault, as a high vault permits a greater arc of upward movementof the lower incisors than a Hat roof. When the second molars erupt, they are prevented from doing sofullv bv the closeness of the bite. •I V The following points are to be observed in diagnosis: 1. The facial angle is less than normal. 2. The alveolar process of the upper and lower maxilla are ex-cessively developed. 3. The upper incisors
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Keywords: ., bookcentury1800, bookdecade1890, bookidverha, booksubjectmedicine
