This is an open access article distributed under the terms of the Creative Commons Attribution NonCommercial ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non commercially, as long as the author is credited and the new creations are licensed under the identical terms.
Excessive gingival display (GD) is a frequent finding that can occur because of various intraoral or extraoral etiologies. This work describes the use of a mucosal repositioned flap for the management of a gummy smile associated with vertical maxillary excess (VME) and hypermobility of the upper lip followed by injection of Botox.
Seven female patients in the age range of 17–25 years presented with a gummy smile. At full smile, the average GD ranged from 6 to 8 mm. A clinical examination revealed hypermobility of the upper lip. A cephalometric analysis pointed to the presence of VME. The mucosal repositioned flap surgery was conducted followed by injection with botulinum toxin type A (Botox) 2 weeks postsurgically.
After 4 weeks, results were definitely observed with a decrease from 8 mm gingival exposure to 3 mm, which was considered as normal GD for an adult during smiling.
For patients desiring a less invasive alternative to orthognathic surgery, the mucosal repositioned flap is a viable alternative. Moreover, Botox is a useful adjunct to enhance the esthetics and improve patient satisfaction where surgery alone may prove inadequately in moderate VME.
A smile is an important nonverbal method of communication and is an interaction between the teeth, the lip framework, and the gingival scaffold.
Goldstein classified the smile line (consisting of the lower edge of the upper lip during the smile) according to the degree of exposure of the teeth and gums into three types: High, medium, or low gummy smiles (GSs) ranged from mild, moderate, and advanced, to severe.
Excessive gingival display (GD) is a clinical finding with many etiologies and may include extraoral or intraoral components. Some extraoral causes of a gummy smile are vertical maxillary excess (VME), hypermobile upper lip (HUL), or a short upper lip. A visual diagnosis of VME is made when the lower third of the face is longer than the remaining thirds; cephalometric analysis (COGS) can be used as an additional aid.
Excessive GD can also be seen in patients with a short upper lip (measured from the subnasale to the inferior border of the upper lip). The average length of the maxillary lip is 20–22 mm in young adult females and 22–24 mm in young adult males.
The best orthodontically treated patients may not be satisfied by the treatment if soft tissue problem is not corrected. Patients desire to look good not only in a static pose but also during dynamic facial expression. Treatment for the most extraoral or intraoral cause of gummy smile, with the exception of a short or hypermobile lip has been well documented. Various surgical and nonsurgical modalities have been described in the treatment of gummy smile which includes Lefort I osteotomy, crown lengthening procedures, maxillary incisor intrusions, microimplants, headgears, self-curing silicone implant injected at anterior nasal spine (ANS) with myectomy, and partial resection of levator labii superioris with muscle repositioning. However, these procedures do not help in reducing the hyperactivity of the muscles and therefore, nonsurgical treatment may be a desirable option.
Recently, the injection of botulinum toxin type A (Botox) has been suggested for treatment of HUL, but this may only provide temporary benefits. Botulinum toxin has been widely used for the treatment of various conditions associated with pain and excessive muscle contraction since the 1970s. Clostridium botulinum is an anaerobic bacterium responsible for its production. Among the eight different serotypes of botulinum toxin that exists, Type A (BTX-A) is the most potent and the most commonly used clinically.
This work presents cases of moderate VME which was treated with lip repositioning for lip lengthening adjunct with Botox in an effort to recreate smile.
Seven female patients in the age range of 17–25 years had a short upper lip with VME but were not willing for surgery. Patients presented to the clinic with the chief complaint of excessive GD.
Inclusion criteria
Pretreatment photographs clearly showed the presence of excessive GD with hyperactive upper lip elevator muscles. Six to eight millimeters of gingival exposure was seen in the incisor region during wide smile which was the main cause for concern for the patient. The upper lip was 20 mm long at rest
(a) The length of upper lip, when measured from subnasale to the vermilion border was 20 mm. (b) Preoperative image of the dynamic smile, which extends to the mesial aspect of the first molar, showing 5–7 mm of gingival display.
Exclusion criteria
Pure skeletal VME, bimaxillary protrusion.
Presurgical cephalometric analysis
COGS showed the skeletal class II pattern with prognathic maxilla with anterior vertical excess between 4 and 18 mm and a posterior excess between 3 and 5 mm.
During the initial visit, all written forms and consents were explained to the patient and signed accordingly. Patient's medical history was reviewed as well. Our research has been conducted in full accordance with the World Medical Association Declaration of Helsinki in 1975 as revised in 2000, and the study has been independently reviewed and approved by an Ethics Committee Review Board at Future University.
Surgical procedure
The infraorbital block was used to avoid thickening of the lip and soft tissues with anesthetic fluid, allowing the surgery to be a more realistic representation of the projected final result.
The surgical area was demarcated with the help of an indelible pencil. The surgical area started at the mucogingival junction and extended 6–8 mm superiorly in the vestibule. Incisions were made in the above mentioned surgical area, and both superior and inferior partial thickness flaps were raised from the maxillary left central incisor to maxillary left second premolar. The incisions were then connected with each other on the distal end in an elliptical outline
(a) The first incision was made at the mucogingival junction. (b) Exposed submucosa after removal of the epithelial discard. (c) Excised mucosal strip. (d) Stabilization sutures in place. (e) Two weeks after lip repositioning surgery, 2.5 units of Botox were then injected at two sites per side in both overlapping points.
Botox injection
Postsurgery although there was a significant improvement in the patient facial profile and smile, there was still about 5 mm gingival exposure during a smile. The dissatisfaction expressed by the patient led us to consider another treatment option. Injecting Botulinum toxin type-A (Botox) was discussed with the patient who was very receptive to the idea which targeted his chief complaint of gummy smile.
Before injecting the solution, the patient underwent a standardized photographic session. A digital camera (Nikon D 60) was used to take the close up perioral, as well as frontal smiling photographs. To standardize the technique, a fixed patient camera distance, a cephalometric head holder, and natural head position were used, care was taken to capture a nonposed spontaneous smile. A measuring scale was used for standardization of the photographs. Adobe Photoshop software was used for the measurements. Botox allergic test was done in each individual prior to Botox injection. After 2 weeks from the surgical procedure, 1 ml tuberculin or insulin syringes can be used as it gauges the dose accurately in minute quantities also.
Botox was diluted according to the manufacturer's recommendations to provide 2.5 units per 0.1 ml by adding 4.0 ml normal saline solution to 100 units of vacuum-dried clostridium botulinum toxin type-A. Under sterile conditions, 2.5 units were then injected at two sites per side in both overlapping points of the right and left levator labii superioris alaeque nasi, levator labii superioris, zygomaticus minor, and levator labii superioris muscle sites
At the 1-week postoperative visit, the patients reported very slight discomfort, with minimal postoperative bruising and extraoral swelling. At the 2-week postoperative visit, the GD on smiling reduced to 2 mm
(a) Preoperative image of the dynamic smile, with moderate maxillary excess at maximal smile position, and an average of 7 mm excessive gingival display was recorded. (b) Postoperative smile after a lip repositioning procedure. (c) Three months after “Botox lip stabilization” treatment. (d) Preoperative at a maximal smile (profile view). (e) Six months after Botox lip stabilization at the maximal smile (profile view).
All patients began to show improvement approximately 15 days after the injections
The cause for GSs can be of skeletal, dentoalveolar, or soft tissue in origin. The skeletal type is caused by excessive growth of the maxilla in the vertical direction and is commonly associated with the long face syndrome.
The surgical correction of the short upper lip and gummy smile by gingivectomy was an alternative treatment, but they are not routinely used to treat hyperfunctional upper lip elevator muscle. Lefort I osteotomy with superior impaction is most commonly adopted to treat skeletal VME, and the most common limitation of this procedure is the congestion of nasal airway function.
Surgical lip repositioning is an effective procedure to reduce GD by coronally positioning the upper lip. In the present case, surgical lip repositioning technique was carried out successfully with tangible results as a dental procedure. Surgical lip repositioning holds promise as an alternative treatment modality in esthetic rehabilitation.
Botulinum toxin type-A (Botox) aids to inhibit releasing acetylcholine by blocking the neuromuscular transmission and binding to acceptor sites on motor or sympathetic nerve terminals. This inhibition occurs as the neurotoxin cleaves SNAP-25, a protein integral to the successful docking and release of acetylcholine from vesicles in nerve endings. When injected intramuscularly at therapeutic doses, it produces partial chemical denervation of the muscle, resulting in localized reduction in muscle activity.
Because of a relapse in results, Miskinyar modified the original technique but did not report when or how much relapse had occurred.
Proper diagnosis and an appropriate case selection are critical for the success of any surgical procedure. Contraindications to mucosal repositioning flap include the presence of a minimal zone of attached gingiva, which can create difficulties in flap design, stabilization, suturing, and severe VME. Degree II VME has gingival and mucosal display of 4–8 mm, whereas >15 mm of soft tissue display is seen in degree III VME. Both categories of VME require a multiple interdisciplinary approach, which may include orthognathic and periodontal surgery or restorative treatment. Previous reports have alluded that thin biotypes have a higher likelihood of relapse.
We report on the use of a minimally invasive surgical procedure for the management of a gummy smile associated with moderate VME (degree II) and HUL. It is less invasive, has fewer postoperative complications, and provides a faster recovery compared to the orthognathic surgery. The mucosal repositioned flap aims to reduce GD by shortening the vestibular depth and Botox aims to the neuromuscular correction and the slight relapse of the surgical procedure. We report on the short-term stability of our results at the 1-year follow-up, the results were extremely satisfactory for both the patient and the orthodontist. Even though Botox has a transitory effect, 6 months posttreatment the gummy smile was still seen to be within the normal range. Hence, depending on the cause and the needs of the patient, this treatment approach could well be used as an alternative procedure for faster and minimally invasive treatment of gummy smile.
Surgical lip repositioning is an innovative and effective way to improve the gummy smile of the patient. This technique is an easy and cost-effective technique to produce a satisfactory result for the patient. As opposed to various other surgical procedures, Botox has proven to be a minimally invasive, effective alternate for the correction of gummy smile caused by the upper lip elevator muscles. It, therefore, can be a useful adjunct to enhance the esthetics and improve patient satisfaction where surgery alone may prove inadequate in moderate VME.
We thank Dr. Noury Adel, oral surgery resident, Mataria Hospital, Egypt, for valuable assistance, and for comments that greatly improved the manuscript.
Financial support and sponsorship
Nil.
Conflicts of interest
The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or non.financial in this article.