# Modified Lip Repositioning Surgery in the Treatment of
## 1 Introduction  
The smile plays a significant role in expression and appearance. Nowadays, achieving a 'perfect smile' has become an essential goal for many patients. Therefore, in addition to teeth, the condition of oral tissues, gingival contour, and lip position all affect the final aesthetics of a smile. Creating the ideal smile is a challenge, as treatment requires motivations planning and a multidisciplinary approach [1]. Excessive gingival display (EGD), commonly known as a 'gummy smile', presents an aesthetic issue and leaves an individual dissatisfied with their smile [2]. One study compared oral health-related quality of life between individuals with and without EGD. Fifty-three patients with EGD and fifty-three control patients were selected in the southern region of Brazil. Through a questionnaire that assessed various aspects, it was observed that the aesthetic satisfaction of patients with EGD was 21.1%, while for control patients it was 78.9% [3]. A smile is defined as pleasant when the upper teeth are fully exposed; however, the degree of gingival exposure considered aesthetically pleasing varies according to the geographic location and culture. Generally, gingival exposure of no more than 2-3 mm is considered pleasant, while exposure exceeding 3 mm is typically regarded as unattractive [4]. Excessive gingival display is a common finding that can occur due to various etiologies. The amount of gingival exposure depends on the position of the smile line, which is defined as the relationship between the upper lip and the visibility of gingival tissues and teeth. There are many factors that contribute to excessive gingival display (EGD), and it is common for this condition to result from the interaction of multiple etiologies [5]. These factors include altered passive eruption, vertical maxillary excess, short upper lip, excessive upperlip mobility, and other conditions that lead to gingival enlargement [4]. To this day, there are still diagnostic and treatment challenges faced by healthcare professionals. Appropriate treatment techniques should be chosen based on the identification and definitive diagnosis of the causes of EGD [4]. Therefore, more than one procedure can be performed to achieve the desired aesthetic [6]. The most well-known technique for correcting a gummy smile is esthetic crown lengthening. However, when crown proportions are appropriate, other treatment approaches should be considered. Surgical lip repositioning (LipStat) can be used when indicated. It is a minimally invasive procedure with fewer post-operative complications compared to orthognathic surgery, which aims to shorten the depth of the vestibular sulcus, limiting the retraction of the elevators of the upper lip muscles [4]. Historically, in 1973, a technique similar to LipStat was first described in the medical literature by [PERSON] and [PERSON] [7]. In 1979, a study already advocated this procedure for correcting EGD in the presence of a short upper lip [8]. Subsequently, some authors proposed variations of the technique, including the retention of lip elevator muscles (the levator labii superioris aleeque nasi, the levator labii superiors muscle, the minor zygomatic muscle, and the major zygomatic muscle), resulting in a reduction in EGD [9]. In 2010, another study recommended myotomy of the levator labii superioris muscle after removing the mucosal band in the sulcus base to minimize tension after suturing the edges and prevent recurrence of the lip position at the anterior height [10]. In 2013, a modification was proposed, maintaining the labial frenum. The reasons for this were to maintain a midline reference and reduce post-operative morbidity [11]. In this case report, the modified lip repositioning surgical technique (MLRS) was used, along with internal sutures, to reposition the upper lip and limit its movement during smiling [12].