This prospective study was conducted in the Department of Oral & Maxillofacial Surgery, Manipal College of Dental Sciences, Mangalore and KMC Attavar Hospital, Mangalore, Karnataka, India from Jan 2011 to June 2012. Institutional ethical committee approval was taken before conducting this study. Abbe-Estlander flap was used for lip reconstruction in 10 subjects who required lip reconstruction following excision of carcinoma of lip, following traumatic maxillofacial injuries causing lip defects or correction of congenital lip deformities.

Detailed history and clinical examination along with routine investigations (Haemoglobin, BT, CT, Urine analysis, Chest X-ray, ECG) were done and all patients were operated under general anesthesia. All the patients were on IV antibiotics in the immediate postoperative period. Patients were recalled at intervals of three weeks, three months and six months for follow up.

All patients reported with traumatic lip injuries or congenital lip deformities having lip defects of 1/3-1/2 of the lip requiring reconstruction were included in study. Patients having Lip defects less than 1/3 of the lip, and could have been managed by primary closure were excluded from the study. Subjects who were medically unfit for surgery or unwilling to undergo surgery were also not included in current study.

The partial-thickness Abbe-Estlander flaps in this series were taken from the middle of the lower lip to replace a portion of the upper lip or from the lateral portion of the upper lip to replace a portion of the lower lip. Lip height to the nose or to the labiomental fold was assessed at the preoperative visit so that postoperative lip height could be correlated to the pre-existing anatomy. The surgery generally involved the following considerations:

All patients were placed on a clear liquid diet for one day, a pureed diet for two days, and then onwards normal diet. Tooth brushing was encouraged. Internal prostheses were always removed. In the office, 2.5 to 3 wk after the reconstruction, the pedicle was injected with 1 to 2 mL lidocaine with epinephrine 1: 2, 00,000. After 10 min, the flap was divided with a No. 10 blade and inset. Mucosal tissue was undermined for closure; however, no significant mucosal adjustments were made. Resorbable sutures were placed in the oral mucosa.

A total number of 10 patients were taken up in the study, age ranging from 35-71 y, mean age being 60 [Table/Fig-1]. Out of 10 patients, 6 (60%) were male and 4 (40%) female [Table/Fig-1]. In all these patients, Abbe-Estlander flap that involved the commissure was used for reconstruction. Supraomohyoid neck dissection on ipsilateral side was done in six patients. In three patients with verrucous carcinoma, only wide excision was done. In the lip bite patient, only reconstruction was done. Abbe-Estlander flap was used in each of the 10 patients to reconstruct the various lip defects. Various sites of the lip defects are shown in [Table/Fig-2] that was reconstructed by using Abbe-Estlander flap. In all the cases single stage except one patient in which two stage, medially based Abbe-Estlander flap was used. The size of the lip-switch flap was usually half the size of the excisional defect. All the patients were evaluated for intra-operative complications like bleeding, difficulty to rotate the flap, difficulty in approximation of margins of flap, infection [Table/Fig-3] and postoperative complications like orocutaneous fistula, fullness or blunting of involved oral commissure, trap-door deformity [Table/Fig-4] before discharging from the hospital. All the patients were recalled at three week, three months and at six months interval to evaluate functional and aesthetic outcomes. All the patients reported for three week follow up only nine patients reported at the time of three months follow up and one patient expired within three months of postoperative due to metastasis to distant organs and six patients reported at the time of six months follow up. In one patient, difficulty to rotate flap (10%) was encountered intra-operatively. In postoperative period, one patient reported with orocutaneous fistula (10%) and one patient had fullness of involved oral commissure (10%) that resulted in permanent unaesthetic oral commissure. Orocutaneous fistula was closed immediately using V-Y closure technique. All the patients had adequate blood supply of flap (100%) [Table/Fig-5].

Two patients with inadequate mouth opening (20%), one of them expired within three months of postoperation and in one patient; second procedure (cheiloplasty) was performed [Table/Fig-5]. Four patients had inadequate oral seal (40%) [Table/Fig-5] and one patient had speech problem (10%) which resolved within a period of three months [Table/Fig-5]. Three patients had asymmetric mouth opening (30%) [Table/Fig-5], and asymmetric lip movement (30%) that resolved within a period of three months except one patient [Table/Fig-5]. One patient developed hypertrophic scar (11.11%) at the end of three month [Table/Fig-5] and 60% of patients had aesthetic oral commissure at the end of three week, 88.88% at the end of three months and 100% patients had aesthetic oral commissure at the end of six months period [Table/Fig-6].

[Table/Fig-6]:

a) Pre operative photograph showing carcinoma of lip; b) surgical defect & flap marking; c) immediate post-operative photograph; d) 3 weeks follow up; e) 3 months follow up; f) 6 months follow up; g) mouth opening at the end of 6 months follow up

Reconstruction of the lip for defects from oncological, congenital, post-traumatic, and, rarely, infectious processes has been described for more than 200 y [1,2]. Lip defects can be classified as partial defects that involve only skin or mucosa or they can be classified as full-thickness defects involving skin and muscle, with or without mucosal involvement [3–5]. Lip defects are also classified by location. Defects can be limited to the cutaneous lip or vermilion or involve the both. Upper lip defects can further be divided into those that involve the philtrum, medial lip, or lateral upper lip. Lower lip defects can also be divided into central or lateral, with or without commissural involvement. The size of the defects is also a helpful means of defining the lip defects. Four categories are commonly considered: one third or less of the lip, one third to two thirds of the lip, more than two thirds of the lip, and defects that result in total loss of one lip in combination with defects in the other lip.Microsurgical techniques have greatly enhanced our ability to restore large parcels of tissue in the head and neck, and the lips and perioral region are no exception. Microsurgical techniques are particularly valuable when local tissues are insufficient for adequate repair of large composite defects [4,5].

The best reconstructions use as much local tissue as possible until free tissue transfer is inevitable, at which point the free flap is joined with the local tissues in as much functional manner as possible. Although, variety of techniques have been proposed for the reconstruction of 1/3^rd to 2/3^rd sized lip defects, none is ideal. It is obvious from the observations made in our present study that Abbe-Estlander flap provides a reliable reconstructive flap. This is supported by the fact that none of our patient had dehiscence or necrosis of the flap. Flanagin[6] used a narrow full-thickness free graft from the lower lip to the upper lip for correction of a flat upper lip. Mild superficial necrosis occurred in all his cases. Multiple functional and aesthetic criteria were used to assess the versatility of Abbe-Estlander flap. The functional criteria were evaluation of mouth opening, presence or absence of lip competence, presence or absence of symmetrical lip movements and the presence or absence of normal speech. The key to optimal restoration of lip function is the reconstitution of the orbicularis oris muscle with its reinnervation [7,8]. The extensive review of literature implies that a two stage procedures is required for restoring adequate mouth opening, but the same was accomplished in our study with single stage alone. Only one patient required a second stage (cheiloplasty) to get adequate mouth opening and enhance oral commissural appearance. Rolda et al., [9] restored the mouth competence and symmetry with a single stage procedure. They did not encounter microstomia in any patient. In literature the major disadvantage of abbe-estlander flaps is microstomia [10].In this study, only one patient suffered from the same. None of patients had persistent speech problems and lip incompetence at three months postoperative. These findings are in consistent with the finding of Zhai et al., [7]. The aesthetic criteria were presence or absence of symmetrical mouth opening, presence or absence of hypertrophic scar and the presence or absence of an aesthetic oral commissure. The best way to achieve a good aesthetic outcome is to use identical or similar tissue for reconstruction of defects [7]. As the Abbe-Estlander flap imports identical tissue for reconstruction, it fulfils the requirements of a good aesthetic outcome. Our study also had good aesthetic results in terms of symmetrical mouth opening and oral competence. Although one patient had a hypertrophic scar but the overall results were satisfactory with regard to cosmetic appearance. Our result is in consistent with the study of Motamedi [11], Bennis and Vegter et al., [12]. This procedure was less mutilating, less stressful and well suited for elderly patients whose general health was not optimal [11]. This flap may represent an alternative to microvascular reconstruction for defects involving up to 1/3^rd to 2/3^rd of the lip. Because of its rich vascularity [13,14]. It is an ideal flap for the irradiated patient and those that have undergone neck dissection. Although, the major limiting factor is its size, it was successfully used for reconstructing 1/3^rd to 2/3^rd of lip defects in this study. Zide MF and Fuselier C [15], Yamauchi et al., [16] and Ali Ebrahimi et al., [17] also stated that Abbe flaps for lower-lip defects typically fill defects comprising 30% to 80% of the total lip width. The Abbe-estlander flap technique has several advantages over other techniques such as: 1) It is safe and a reliable flap with an excellent blood supply that affords versatility in flap design even after bilateral neck dissection. 2) Simple to perform, and provides functionally and aesthetically pleasing result for reconstruction of 1/3rd to 2/3rd sized lip defects. 3) Safer and less mutilating for elderly patients with multiple morbidities, who represent a poorer operative risk. 4) Change of appearance is very minimal and very acceptable for the patients. 5) Improves functional results in terms of speech and symmetrical lip movements [10,14,16].

Even though maxillofacial reconstructive surgery has undergone a sea change from the use of traditional flaps to the present day microsurgical free tissue transfer, Abbe-Estlander still holds in a position as a reliable method of lip reconstruction. Our experience with 10 patients with Abbe-Estlander flap reconstruction has been encouraging and the result obtained was extremely satisfactory.