to diagnose the loss and plan the restoration. (Sometimes this replacement of the first stage of any plastic operation can be imitated by moving putty flaps upon the plaster cast as one would the flesh.) In planning the restoration, function is the first consideration, and it is indeed fortunate that the best cosmetic results are, as a rule, only to be obtained where function has been restored. Perhaps the first question that arises in any case is the relative expediency of attempting surgical repair or mechanical camouflage, and a satisfactory decision can be arrived at only as a result of long experience. Sometimes in the end the repair undertaken is a compromise between surgery and mechanics, the decision being based on the severity and multiplicity of the operations needed to effect a surgical cure, and on the patient's lack of stamina; or on factors outside the present discussion. One looks forward with confidence to a plastic millennium when, given a healthy patient and no time restrictions, it will be possible to cope surgically with any reasonable facial loss.
The restoration is designed from within outwards. The lining membrane must be considered first, then the supporting structures, and finally the skin covering.
Lining Membrane.—Omission to provide a lining membrane for mucous cavities has in the past been the supreme cause of plastic failure. Keegan quotes a President of the Royal College of Surgeons in 1863, as mournfully describing how a well-shaped plastic nose is prone to wither away on the patient's face. The author has seen examples of a similar occurrence in recent times, for want of a lining; and many cases of post-operative nasal stenosis, microstoma, and contracted eye-socket are traceable to the same cause. Even to this date the author has frequently to perform a second rhinoplasty upon patients who, during a portion of their plastic career, proudly flaunted new and shapely noses, which gradually diminished in size as a result of ulcerative processes within.
Mucous membrane is not often available except in the smaller mouth defects, and the results of free mucosal grafts have been poor. Recourse, therefore, is had to skin, either in the form of flaps or grafts. In its new and moist condition of existence the surface epithelium appears macroscopically to approach the mucosal type. In the nose, the formation of the mucosal lining by swinging turbinates and septum into the desired position has been successfully used on a number of occasions. When not available, an epithelial lining is usually provided by means of cheek and bridge flaps turned skin inwards. If these flaps are not available, their place is taken by a Thiersch graft. Similar type flaps from the margin of the defect or Thiersch grafts are used in the rebuilding of the ocular aspect of new eyelids. In the smaller lesions of the oral cavity, the new cheek or lip is lined by the advancement of mucous flaps from the intact portions. Mucous membrane flaps are also used to replace