**2. Materials and method**

In this study, 11 patients of at least 3 years of follow-up (between 2011 and 2019) are included. Following preauricular incision, a pouch is created by lifting the skin flap at the mouth corner upward and downward. After the outer edge of masseter muscle is found and after a back parallel line is drawn starting from 1 to 1.5 cm away from the zygomatic arch, a point is marked on that line 3–3.5 cm away from tragus. Masseter nerve is found by parallel dissection to muscle fibers between superficial and deep lobes of masseter muscle, approximately at 1.5 cm deep of superficial musculoaponeurotic system (SMAS) [2]. Nerve is dissected at its full length, the branch that goes to deep lobe is preserved, and the superficial branch is determined as the recipient nerve. On inner side of the thigh, adductor longus muscle is palpated, a parallel incision to that muscle is made, and gracilis muscle is found positioned medially to adductor longus muscle (**Figure 1**). After dissection of the pedicle, markings on the muscle, 3 cm apart from each other, are made with absorbable sutures, which are going to define the entrance site of the central predicle (**Figure 2**). Branch of the obturator nerve to gracilis muscle is tracked to the site of origin from the main nerve

#### **Figure 1.** *View of the gracilis muscle and its pedicle drawn on skin.*

**Figure 2.** *Gracilis free muscle flap marked at 3 cm intervals.*

*Reanimation of Mouth Corner with Free Gracilis Muscle Flap DOI: http://dx.doi.org/10.5772/intechopen.105909*

**Figure 3.** *Removal of the muscle flap with straight intestinal stapler.*

body. About 1/3–2/3 anterior segment of the muscle, 2–3 cm longer than the distance between zygomatic arch and mouth corner, is taken using a straight intestinal stapler (**Figure 3**). The size of the segment that is going to be used is determined according to the entrance site of the pedicle on the muscle. First of all, to technically facilitate the procedure, nerve of the gracilis muscle flap is repaired and sutured to the recipient masseter nerve. Then, flap is transferred to facial artery and vein, which had been prepared as recipient vessels. Upper end of the muscle is sutured to zygomatic arch with 2/0 Polydioxanone (PDS). Distal end of the muscle is divided in three parts: upper part is sutured to the upper side of the lip and to the base of nose, lower part is sutured to the side of the lower lip, and middle part is sutured to the mouth corner. After the operation, patient's mouth corner is sutured as a static strap, in a position that muscles stay tight and constricted, symmetrical to the contralateral side. A drain is placed next to the pedicle, without completely closing the preauricular incision, bleeding control on the end of the muscle and circulatory control with Doppler Ultrasound are performed. Patients are immobilized for 5 days in bed. No anticoagulants were used and only be used local heating with floor lamp. After day 5, with observation of normal circulation following mobilization, preauricular incision is closed. Average time that patients start to feel the first muscle contractions is observed to be around 2 months. After contractions begin, Transcutaneous Electrical Nerve Stimulation (TENS) device is used on patients for 20 minutes four times in a day. The traction of the mouth corner is started to be observed around 6–8 months on average. Patients' muscle power being increased, maximum muscle strength is achieved approximately 1.5–2 years on average. After patients start to pull the lip corner, physiotherapy is started. Advices of practicing control on smiling movements with a mirror, guidance on patients' social lives, which may lead to all day smiling, and advice of watching a comedy movie every other day were made to patients.
