210 AXl.MAL DHNTIS'IRV. 



scniblcs the abnormality of the incisors known as "erosion" 

 or "ilenuchni^." It is a harmless condition in itself, Ijut 

 should be regarded as evidence of a poor quality of teeth. 



Pathological Anatomy — The incfdent occurs most fre- 

 fjuently to the superior molars, Init is seen also in the in- 

 ferior ones. The splitting may be limited to the crown or 

 may extend through the entire length of the tooth. In the 

 greatest number of cases it terminates just l)eyon(l the al- 

 veolar margin on the lingual side of the tooth, dividing it 

 into two very unequal segments, one of which comprises the 

 principal part of the tooth, and the other a thin shell consist- 

 ing of the crusta petrosa and external enamel. 



In other instances the tooth is broken into three seg- 

 ments — two lateral shells and a central large one, which in- 

 cludes the fang and roots. 



In rare cases a superior molar is divided into two equal 

 portions by splitting from table to root between the two 

 layers of the internal enamel. 



The condition is complicated with considerable osteitis 

 and necrosis from lateral pressure against the alveolar mar- 

 gin, and from the decomposition of impacted food. In the 

 old case the opposing tooth will be found elongated and the 

 tongue and cheek may be severely wounded from friction 

 of the protruding segments. 



Treatment — Removal of the tooth and leveling of the 

 opposing arcade. (See extraction.) 



FOREIGN BODIES IN THE MOUTH. 



Foreign bodies become lodged in the mouth of all the do- 

 mestic animals. In the horse and ox pieces of corncob and 

 sticks of wood become wedged between the superior arcades, 

 and pins, tacks and splinters lodge between the teeth: In 

 the dog, cat and i)ig, pieces of bones are frequently found. 



