206 VETERINARY DENTAL SURGERT. 



removing every particle, or the trephine will become 

 clogged. A common scalpel, Fig. 47, may be used 

 for making an incision through the skin, and if 

 it has a straight, thin bone or ivory handle, the 

 soft structures including the periosteum can be 

 easily removed by pushing the end of the handle 

 underneath them and raising them up. Some 

 operators prefer a crucial incision, others a T 

 I incision. If either of the latter forms of incis- 

 ion are made, the opening, as a general thing, 



Swill close too soon. The flaps also interfere 

 with the washing and dressing of the sinuses; 

 they sometimes become swollen and very pain- 

 ful to the touch. By making the circular in- 

 cision, the operation is more readily performed 

 and the edges of the wound do not interfere 

 with the dressing. 



3d. The removal of the bony plate is 

 accomplished by the use of the trephine, of 

 which there are several kinds, all of which will 

 do good work as long as they are kept sharp. 

 At present they are all made with a center bit. 

 FI'G. 47. The other instruments necessary are a scal- 

 in^Scar- P e ^> a stron g P a "" ^ dressing forceps and a 

 P els - sequestrum forcep, Fig. 49, with which to 

 remove the piece of bone when it is not brought out 

 by the trephine. The bit should be extended one- 

 fourth inch beyond the saw of the trephine; this, 



