Abstract
Classic cinch suture narrowing of the nasal alar base by medially suturing the bilateral nasolabial soft tissue with one long suture has a limited effect. The modified cinch method described in the present study anchors non-absorbable sutures to the bilateral lower border of the piriform rim and provides optimal direction, position, and stability. The sutures can be shortened and the strength kept stable while the surgical wounds heal. Separate bilateral sutures can also reduce interference and distortion from nasotracheal intubation and make the nasolabial profile more symmetrical. Seventeen consecutive cases of maxillary Le Fort I osteotomy were analyzed. The nasal and alar base width changes were 0.4 ± 1.2 mm and 0.1 ± 1.1 mm, respectively, and the widening rate was only 1.1%. Compared with the results of other studies, postoperative nasal flaring was well controlled using the modified cinch suture anchored to the bilateral lower border of the piriform rim described in this study.
Repositioning the jawbone to remodel how the face looks is the basic purpose of orthognathic surgery. The focus of the midface profile is the area comprising the nose and lips. Maxillary orthognathic surgery, especially Le Fort I osteotomy, is the most practical and relevant operation for the nasolabial profile. Subnasal soft tissue and muscle are detached at the beginning of the osteotomy, and the loss of properly reattached direction makes the alar-facial groove shallow and the nose wider, especially the alar base, which is where the nasal alae show flaring changes. These changes reduce the sense of three-dimensionality of the lower nasal pyramid. The procedure of choice to control nasal alar flaring is the alar cinch suture technique.
The alar cinch technique was developed by plastic surgeons to narrow the nasal alar width and to try to improve the appearance of patients with a flaring nose. This classic alar cinch technique was then used in later years for maxillary orthognathic surgery. The cinch suture uses a non-absorbable suture and anchors the bilateral alar fibroareolar tissue; these mutually tighten each other medially.
Theoretically, tightening the bilateral nasal alar muscle or fibroareolar tissue will help reduce postoperative alar widening. Nevertheless, some classic cinch suture studies have reported that even though the alar flaring is controlled, the nasolabial angle increases.
The classic alar cinch technique uses a single suture to tighten the bilateral alar-facial groove soft tissue or muscle. The average alar width is about 35–40 mm, and at this length, a cinch suture should be sufficiently strong; the strength of the suture is inversely proportional to its length. One modified technique consists of passing the suture through the nasal septum, which is supported by dense cartilage. This modified method is more efficient for controlling nasal alar base widening. The type of alar-facial groove tissue that the suture grasps is important for controlling the appearance of the alae. Loose tissue reduces the efficiency of the cinch. Compared with muscle or fibrous tissue, a denser hypodermis provides better anchor tissue for the procedure. Some modified cinch techniques have tried to improve the approach by reinserting the needle from the extraoral skin to suture the hypodermis of the alar-facial groove. Furthermore, a trans-septal modified alar cinch suture technique involving combined extraoral skin reinsertion and passing the sutures through the nasal septum has been used successfully.
Conventional nasotracheal intubation will also interfere with jawbone repositioning and soft tissue closure. Using the classic or a modified single alar cinch suture technique for the bilateral nasal alae, the tube side will interrupt the medial movement of the ipsilateral ala. To facilitate this nasolabial operation, some oral surgeons use submental instead of nasotracheal intubation.
A new modification of the alar cinch suture technique was developed in the present study: bilateral alar fibroareolar tissue is cinched by separately dragging the sutures to the lower border of the piriform rim ( Fig. 1 ), which reduces the effect of intubation and makes the alae more symmetrical ( Fig. 2 ). This method has the shortest suture, and the anchors on the piriform rim are secured to bone; thus, the modifications allow the tissue to retain its structure and strength during healing.
Materials and methods
Seventeen consecutive patients who underwent a maxillary Le Fort I osteotomy, advancement or impaction repositioning, or a combined anterior maxillary and mandibular osteotomy at a medical centre in Tainan, Taiwan, were enrolled in this study.
Modified alar cinch suture technique
For the Le Fort I osteotomy, the bone cutting line was at least 5 mm above the piriform base. After the maxilla had been repositioned, the segments were fixed with a miniplate (DePuy Synthes). The anterior nasal spine was contoured if the maxilla was advanced more than 2 mm. The anchor point was located on the lower border of the piriform rim at one-third the distance from the most lateral margin. A hole for 1.5-mm diameter wire was made with a bone drill (Stryker) ( Fig. 3 A) . The fibroareolar tissue of the most lateral inferior point of the alar-facial fold was grasped using Adson tissue forceps. The tissue was cinch-sutured with 2–0 non-absorbable polypropylene. The surgical needle was inserted through the dense hypodermal layer just beneath the lowest end of the alar-facial fold. The sutures were passed through the piriform rim anchor point and then tightened until the suture fold was fixed to the bone surface ( Fig. 3 B). The same procedure was done separately on the contralateral side. The maxillary vestibule soft tissue and mucosa were closed using the V–Y method. All of the patients had undergone orthodontic treatment before orthognathic surgery, and all surgical procedures were done by the same oral surgeon (C.Y.Y.).
