=Dieffenbach Method.=—To facilitate the mobility of the lip flaps, Dieffenbach has added two additional incisions on either side of the nose, in circular fashion, encircling the alæ of the nose, as shown in Fig. 183. This procedure is hardly ever necessary in harelip, and truly applies to the restoration of a considerable loss of tissue of the upper lip occasioned by the extirpation of cancerous growths, although clefts of the median variety might be corrected thereby. The wound thus formed appears as in Fig. 184. The sutures are placed as in Fig. 185. [Illustration: FIG. 183. FIG. 184. FIG. 185. DIEFFENBACH METHOD.] Instead of the semicircular incisions a horizontal incision on either side of the cleft may be made just below the nose with the same object in view, the wound being sutured in angular form similar to the method of Nélaton. _Congenital Bilateral Labial Cleft_ The occurrence of bilateral cleft of the lip is much rarer than the variety just described. According to Fahrenbach, out of 210 cases he found only 59 of some degree of the bilateral form. The degrees of deformity have already been mentioned. The correction of these types of fissure is very similar to that of the single cleft variety except that the operations for the latter are simply duplicated on the opposite side. Particularly is this true in cases of the first degree, while in the severer forms, modifications of such methods as have been described must be resorted to, according to the nature and extent of the defect. It must always be the object of the surgeon to save as much of the presenting tissues as is possible, to avoid traction on the tissues and to overcome the consequent thinning out of the entire upper lip or the flattening so often seen in the lips of these patients. The correction of this flattening of the lip following operations for the restoration of the lip will be considered later. The following operations for the correction of bilateral cleft may be regarded as fundamental: =Von Esmarch Method.=—Von Esmarch advocates an incision circling the central peninsula just sufficient to remove the bordering cicatrix. Both lateral borders are vivified along the limit of the vermilion borders (see Fig. 186). He advises suturing the mucous-membrane flaps which he retroverts to form a basement membrane, upon this he slides the skin flaps, and sutures them as shown in Fig. 187. The best results are obtained when the lip is sufficiently detached from the jaw by deep incisions beginning at the duplicature of the mucous membrane. This insures the necessary mobility, and is considered by him the most important step in the operation. [Illustration: FIG. 186. FIG. 187. VON ESMARCH METHOD.] =Maas and von Langenbeck Methods.=—Maas and von Langenbeck vivify the median peninsula in square fashion, as shown in Fig. 188, and suture the fresh margins of the flaps, as shown in Fig. 189, according to Fig. 190. [Illustration: FIG. 188. FIG. 189. FIG. 190.