Botulinum Toxin for the Treatment of Excessive Gingival Display: A Systematic Review

A Systematic Review and Meta-Analysis Comparing Surgical and Nonsurgical Treatments for Excessive Gingival Display

Excessive gingival display (EGD) is defined as more than 2 mm of gingiva display above the maxillary incisors at maximum smile. Various skeletal, dental, and soft tissue etiological factors for EGD have been suggested. This study assessed the effectiveness and stability of surgical (SX) and nonsurgical (NSX) interventions for correction of EGD through a systematic review and meta-analysis following PRISMA 2020 guidelines. An electronic search of Ovid MEDLINE, EMBASE, CENTRAL, Scopus, Web of Science, and LILACS was conducted (2010-2023). Results were expressed as mean change in gingival display using the random-effects model at 1, 3, 6, and 12-month follow-up. At 1 month, SX and NSX treatments yielded a comparable mean reduction of 3.50 mm (2.13-4.86) and 3.43 mm (2.67-4.19) in gingival display, respectively. However, by 6 months, NSX treatments showed a reduction of 0.51 mm compared to 2.86 mm with SX treatments. SX outcomes remained stable past 6 months, while NSX outcomes partially relapsed at 6 months and returned to baseline levels at 12 months. Notably, NSX treatments were more effective in cases with mild initial EGD, while SX treatments showed a better outcome in severe cases. To draw more robust conclusions regarding the treatment outcomes, future primary studies of greater rigor are required.

Application of Botulinum Toxin at the Yonsei Point for the Treatment of Gummy Smile: A Randomized Controlled Trial

BACKGROUND

Demand for less-invasive procedures for treating gummy smile, such as botulinum toxin A injections, has increased substantially over the years. Meanwhile, the optimal injection site for botulinum toxin A injection is debated. The authors aimed to investigate the efficacy of botulinum toxin A injection at the Yonsei point for treating gummy smile.

METHODS

In this double-blind, single-site, randomized clinical trial, healthy participants with a gummy smile (anterior gingival exposure of ≥3.0 mm) were enrolled and randomized (1:1 ratio) into two groups. The experimental group was administered 6 U of botulinum toxin A at the Yonsei point (a single-site injection of 3 U to the right Yonsei point and 3 U to the left Yonsei point), and the control group received the same dose in the bilateral levator labii superioris alaeque nasi muscle sites. The patients were assessed at baseline and 4, 12, 24, and 48 weeks after the first injection using a digital vernier caliper.

RESULTS

A total of 49 participants were enrolled. Anterior and bilateral posterior gingival exposure were reduced at 4, 12, and 24 weeks ( P ≤ 0.05) and returned to baseline at 48 weeks in both groups; there was no difference between the groups at these time points. The increase in satisfaction among patients was significant, and few adverse events were observed.

CONCLUSION

Both the Yonsei point and the levator labii superioris alaeque nasi muscle site can be used as botulinum toxin A injection sites for treating gummy smile.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

Mechanism and clinical use of botulinum neurotoxin in head and facial region

PURPOSE

Botulinum neurotoxin (BoNT) is a biological toxin produced by Clostridium botulinum. BoNT is a potent toxin extensively used in therapeutic interventions. This review provides an updated overview of the mechanisms of action and clinical applications of BoNT in head and facial region.

STUDY SELECTION

MEDLINE/PubMed searches were conducted using the terms "botulinum neurotoxin" and "dentistry" along with a combination of other related terms. In addition, studies were manually selected from reference lists of the selected articles.

RESULTS

The Food and Drug Administration in the United States initially approved BoNT to treat strabismus, blepharospasm, and hemifacial spasms. The use of BoNT in dermatology and cosmetics has been widely established and has created a revolution in these fields. Over the years, its applications in various medical specialties have expanded widely. Owing to its safety, efficacy, and long duration of action, it is well-accepted by patients. BoNT/A and BoNT/B are widely used in clinical practice. Several off-label uses of BoNT in the dental fraternity have yielded promising results. We have elaborated on the speculated mechanism of action, dosage, effective sites of injection, and adverse effects of each therapeutic application. The various clinical indications for BoNT include bruxism, myofascial pain, temporomandibular joint dislocation, hemifacial pain, orofacial dystonia, facial paralysis, chronic migraine, and trigeminal neuralgia.

CONCLUSIONS

BoNT is a safe treatment that can be used effectively, provided that the clinician has adequate knowledge regarding the mechanism, injection techniques, and local and systemic side effects and that it is administered cautiously and purposefully.

Non-Surgical Management of the Gingival Smile with Botulinum Toxin A-A Systematic Review and Meta-Analysis

Currently, concern about facial attractiveness is increasing, and this fact has led to orthodontics in adult patients being an increasingly demanded treatment, and with it, multi-disciplinary work. When it is caused by a vertical excess of the maxilla, the ideal solution is orthognathic surgery. However, in borderline cases and when the cause is hyperactivity of the upper lip levator muscle complex, alternative conservative solutions can be considered, such as the application of botulinum toxin A (BTX-A). Botulinum toxin is a protein produced by a bacterium and causes a reduction in the force of muscle contraction. The multi-factorial nature of the smile requires an individualized diagnosis in each patient, since there are multiple ways to treat the gummy smile (orthognathic surgery, gingivoplasty, orthodontic intrusion). In recent years, interest has grown in the simplest techniques that allow the patient to quickly return to their usual routine, such as lip replacement. However, this procedure shows recurrences in the first 6-8 post-operative weeks. The main objective of this systematic review and meta-analysis is to analyze the effectiveness of BTX-A in the treatment of gummy smile in the short term, to study its stability, and to evaluate potential complications. A thorough search of the PubMed, Scopus, Embase, Web of Science, and Cochrane databases and a grey literature search were conducted. The inclusion criteria were studies with a sample size greater than or equal to 10 patients with gingival exposure greater than 2 mm in smile, treated with BTX-A infiltration. Those patients whose exclusive etiology of their gummy smile was related to altered passive eruption, gingival thickening, or overeruption of upper incisors were excluded. In the qualitative analysis, the mean pre-treatment gingival exposure ranged between 3.5 and 7.2 mm, reaching a reduction of up to 6 mm after infiltration with botulinum toxin at 12 weeks. Although multiple muscles are involved in the facial expression, the muscles par excellence selected for blockade with BTX-A were levator labii superioris, levator labii superioris ala nasalis, and zygomaticus minor, infiltrating from 1.25 to 7.5 units per side. In the quantitative analysis, the difference in mean reduction between both groups was -2.51 mm at two weeks and -2.24 mm at three months. The benefit of BTX-A in terms of improvement of gummy smile is demonstrated, as a significant reduction in gummy smile is estimated by BTX-A therapy two weeks after its application. Its results gradually decrease over time, however, they stay satisfactory without returning to their initial values after 12 weeks.

Full-Mouth Rehabilitation of a Patient with Gummy Smile-Multidisciplinary Approach: Case Report

The impairment of aesthetic function leads to a decreased quality of life. An unaesthetic smile due to excessive gingival exposure demands, most of the time, a complex treatment in which the objective is the vertical reduction of the amount of exposed fixed gingiva by obtaining a complete exposure of the anatomical crown of the teeth and restoring the ideal dimensions of the biological width. This paper presents a case of a 48-year-old female patient who was unsatisfied with her aesthetics and had disturbed masticatory function due to the absence of some posterior teeth. The cone beam computed tomography was performed to evaluate the facial and dental morphology. The treatment plan included diode laser and piezo-surgery utilization for the frontal area of the upper arch and implants to restore the distal area of the lower and upper arch. Zirconia ceramic was used for the final restorations. This complex and multidisciplinary full-mouth rehabilitation lasted for two years, and the patient was pleased with the result. This case showed that a well-established treatment plan is necessary to obtain long-lasting results. The use of adequate procedures and equipment ensures a predictable result.

Effects of Dose and Injection Site on Gingival Smile Treatment with Botulinum Toxin Type A: A Prospective Study

BACKGROUND

Botulinum toxin type A is an easy and efficacious treatment for gingival smile. However, the optimal dose and injection site are controversial. The authors compared the reduction in gingival exposure using two methods with different doses and injection sites.

METHODS

In this prospective self-controlled study, healthy participants with gingival smile (anterior gingival exposure of >3 mm) underwent two treatment methods. First, participants received a single-point injection of 2 U of botulinum toxin type A per side (simplified method). After 8 months, the individualized method was performed with 2 to 5 U of botulinum toxin type A (total, 4 to 10 U), which was injected at one or two sites according to pretreatment severity. Data were collected at baseline and at 4, 12, and 32 weeks of follow-up.

RESULTS

Fifty-five participants were enrolled. Anterior gingival exposure and bilateral posterior gingival exposure were significantly reduced 4 and 12 weeks after botulinum toxin type A injection ( P ≤ 0.05) with both methods. These parameters returned to baseline by 32 weeks ( P > 0.05). Posttreatment anterior gingival exposure at 4 weeks and 12 weeks with the individualized method was significantly lower compared with the simplified method (both P ≤ 0.05). Patient satisfaction with the individualized method was preferred compared with the simplified method ( P ≤ 0.05). Few adverse events were observed with both methods without statistical significance.

CONCLUSION

It is necessary to increase the injection dose and tailor the injection site according to the pretreatment severity of anterior gingival smile.

The Influence of Gingival Exposure on Smile Attractiveness as Perceived by Dentists and Laypersons

Background and Objectives: Smile is an important mark of beauty, and smile attractiveness can be influenced by various factors, one of these being the amount of gingival exposure. The aim of this research was to evaluate the perception of an ideal gingival exposure in smile in a sample of Romanian dentists and laypersons, and to find out what is the most important aspect that influences the smile perception for the respondents included in the study sample. Materials and Methods: An online survey was conducted between 3 February 2020 and 31 October 2020. The authors developed a short questionnaire consisting of 7 items. The first four items investigated the respondents’ age, gender, profession and whether or not they underwent an orthodontic treatment in the past. For items 5 and 6, participants had to choose the most and the least attractive amount of gingival exposure, and for the last item they had to choose the factor that mostly influences the smile attractiveness in their opinion. Results: 235 questionnaires remained in the study. The sample consisted of 194 women and 41 men, 162 laypersons and 73 dentists. The average value for the most attractive amount of gingival exposure was −0.57 ± 2.407 mm, with a median value of 0 mm while the average value for the least attractive amount of gingival exposure was 1.43 ± 3.785 mm, with a median value of 4 mm. The differences between the most or least attractive gingival exposure perceived by the participants were not significant according to gender or professional category (p > 0.05), but, when compared between having or not having an orthodontic treatment in the past the differences were statistically significant (p < 0.05). As such, participants who had an orthodontic treatment in the past perceived a significantly higher value for the most attractive gingival exposure, and a significantly higher value for the least attractive gingival exposure (p = 0.026) than the participants who didn’t have an orthodontic treatment in the past. As for the factor that mainly influences smile attractiveness, laypersons chose significantly more frequent white teeth or aligned teeth (96%, 71.7%) while dentists chose significantly more frequent a gingival exposure between 0−3 mm (70.4%) as smile factors for an aesthetic smile (p < 0.001). Conclusions: In this study sample, the respondents considered that the most attractive smile involved a covering of 0.57 mm (in average) of the upper incisors by the upper lip. Although smile attractiveness did not appear to be influenced by gender or profession in this study population, it was influenced by previous orthodontic treatment. The participants’ roles of dentist or layperson influenced the factors chosen for an aesthetic smile.

The role of botulinum toxin A in the management of different types of excessive gingival display: a systematic review

Background An aesthetic smile displays a symmetrical 2 mm or less of gingival tissue. A smile with over 3 mm of gingival display can be deemed socially unaesthetic, impacting on a patient's psychosocial status. This literature review aimed to explore the role of botulinum toxin A as a treatment modality for different types of excessive gingival display (EGD) and appropriate treatment protocols.Methods A systematic search of the literature dating from 1980 onwards was conducted using electronic databases (Medline, Scopus and Web of Science). The Fowkes and Fulton quality assessment was undertaken to review the level of bias.Results Nine prospective studies were assessed for the number and site of injections, the unit dosage, the reconstitution and the improvement of EGD. Guidelines for treatment of EGD were constructed for operator consideration.Conclusions The data from this study elucidated that botulinum toxin is an effective treatment for all types of EGD caused by hyperfunctional smile muscles. It can be regarded as a safe treatment that reversibly improves facial aesthetics in patients suffering from gummy smile due to hyperactive musculature. Botulinum toxin was confirmed to be useful as a diagnostic tool and palliative treatment, as well as an adjunctive therapy in the treatment of a gummy smile.

Botulinum toxin A in dentistry and orofacial surgery: an evidence-based review - part 2: cosmetic applications

Objective An evidence-based review on the role of botulinum toxin type A (BoNTA) on diverse cosmetic applications of interest to dental practitioners and allied specialities. In this context, to identify the cosmetic treatments that have an evidence-based rationale against areas requiring further research, with a view to assess the safety and efficacy of BoNTA.Data source and selection A comprehensive search was conducted using Cochrane Library of Systematic Reviews, Cochrane Central Register of Controlled Trials, and PubMed (Medline) electronic databases. Thirty-nine studies of variable quality were included. The Best Evidence Topics (BETs) Critical Appraisal Tool was used to facilitate the quality assessment of relevant studies.Data extraction Based on current level II evidence, BoNTA was safe and effective to improve facial contour, reduce volume and thickness of bilateral hypertrophic masseter. Conservative doses using a combined approach of BoNTA and hyaluronic acid was recommended as a safe and effective treatment for perioral enhancement supported by level II evidence. There was limited evidence, not higher than level III, to support BoNTA effectiveness for gummy smile associated to perioral musculature hyperactivity, while jawline sculpting targeting the platysma muscle had lower level IV evidence up to this date.Conclusion BoNTA has been widely used off-label for the investigated cosmetic orofacial conditions, with reports of 'good patient and practitioner satisfaction'. However, there is limited high-quality evidence to support the long-term safety and effectiveness of repetitive BoNTA injections. Additionally, no studies were found that provided a cost-effectiveness evaluation of BoNTA formulations against other current cosmetic interventions. Well-designed clinical trials, including long-term follow-up, would help to provide robust evidence-based recommendations for clinical practice, supporting BoNTA popularity, independently or in a combined approach.

Myomodulation using hyaluronic acid fillers as an efficient and innovative treatment for gummy smile: A case report

Myomodulation (MyoMo) using hyaluronic acid (HA) fillers can be considered as a novel aesthetic treatment for gummy smile (GS). However, literature is still lacking information about this procedure. For this reason, the aim of the present case report was to describe a technique for MyoMo with HA as an efficient alternative for the management of GS. A 36-year-old male patient attended to our clinic complaining about excessive gingival exposure when smiling. After a clinical and digital assessment, poor bone support was observed in the premaxilla area, resulting in an increasing contraction of the levator labii superioris alaeque nasi and levator anguli oris. A multilayer approach with HA filling was performed in order to impair muscle movement and limit excessive lip elevation. As a result, a reduction on the elevation of the upper lip while smiling was achieved, and an improvement on GS was achieved. Thus, it can be proposed that Myomo with HA acid may be an effective treatment for GS, with lasting and satisfactory results. However, high-quality studies are required in order to compare patient's satisfaction with this treatment and any other possible alternative.

A Novel Concept of Combined High-Level-Laser Treatment and Transcutaneous Photobiomodulation Therapy Utilisation in Orthodontic Periodontal Interface Management

This case report is aimed to demonstrate the synergetic effects of λ940 nm laser photobiomodulation (PBM) therapy in augmenting the advantages of high-level-laser treatment (HLLT)-mediated reaction orthodontic periodontal interface management. Materials and Methods: A 32-year-old female who presented with a persistent gummy smile of upper incisors and low upper midline frenum attachment post-orthodontic treatment, was seeking a better smile appearance. She had a history of delayed wound healing without underlying medical conditions; otherwise, she was fit and healthy. She underwent laser ablation of the upper midline frenum and gingivoplasty of the upper incisors region with λ940 nm and λ2780, respectively, as well as transcutaneous PBM therapy (λ940 nm) to accelerate wound healing. The laser protocols were as follows: λ2780 nm: power output—2 W, pulse width—60 μs, free running pulse (FRP), spot area—0.0016 cm², pulse repetition rate—25 pulses per second (s), 80 mJ/pulse, 90 s, λ940 nm: 1.2 W, continuous wave (CW) emission mode, 300 μm, 60 s; whereas the adjunctive λ940 nm induced-PBM parameters were as follows: power output—1.4 W, CW—120 s, single application, spot area—2.8 cm². An acceleration of the wound healing was observed on the 4th day of treatment with no immediate or post-operative complications. The results showed no functional or aesthetic relapses at a long-term follow-up of 6 months. The authors concluded that λ940 nm laser-PBM can provide a synergetic effect to HLLT in accelerating wound healing and offering a precision smile with minimal to none post-operative complications. It is safe and justifiable to utilise dual therapy over the conventional methods, which serves our patients’ needs in our daily practice and in various clinical indications. The concept and laser protocols of this clinical case report can pave the roadmap for future extensive studies.

Botulinum Toxin A in the Management of a Gummy Smile: A Clinical Controlled Preliminary Study

BACKGROUND

Botulinum toxin type A (BTX-A) is recent technique for the treatment of gummy smile.

OBJECTIVES

The aim of this randomized controlled preliminary clinical trial was to evaluate the effects of BTX-A on excessive gingiva display (EGD) reduction, muscle activity, and patient satisfaction at 2, 8, 12, 16, 21, and 25 weeks.

METHODS

Group 1 (G1) received 4 points of BTX-A application (2 U/point) for relaxation of the levator labii superioris alaeque nasi and levator labii superioris muscles; Group 2 (G2) received 2 points of BTX-A (2 U/point) for relaxation of only the levator labii superioris alaeque nasi muscle.

RESULTS

A high dropout of patients from follow-up sessions occurred. Therefore, because of this data limitation, the results were considered a preliminary outcome. At 2 weeks, there was a significant difference between baseline regarding the reduction of EGD in G1 and G2, reduction in muscle activity in G1, and increased satisfaction in G1 and G2. At 2 weeks, there was no difference between the 2 groups. Statistically significant EGD reduction was maintained until 16 weeks in G2 and 25 weeks in G1. After 14 days there was a gradual recovery of muscle activity in both groups until recovery of baseline values by 25 weeks. Patients' satisfaction with treatment lasted 21 weeks in G1 and 16 weeks in G2.

CONCLUSIONS

Increasing the number of BTX-A injection points resulted in a prolonged effect regarding EGD reduction and patient satisfaction but did not increase the intensity of the outcome. However, due to the high dropout of patients, this is a preliminary conclusion and further studies are necessary to confirm these results.

LEVEL OF EVIDENCE: 2

Botulinum Toxin Injections as an Adjunct to Surgical Lip Repositioning For Gummy Smile Treatment

BACKGROUND

An attractive smile depends on the proper proportion and arrangement of lip, teeth gingiva scaffold. The ideal smile is the exposure of the entire length of maxillary teeth with 1 mm gingiva. A gingival display exceeding 3 mm is unpleasant and termed "gummy smile (GS)." Lip repositioning is a simple surgical procedure intended to minimize the gingival display by removing a strip of mucosa and shortening the vestibular depth. Botulinum toxin injecting overactive muscles with measured quantities results in a reduction of muscle activity, relaxing the lip muscles and decreasing upward pull on the lip. There are some contraindications: patients with short lips and gingival exposures less than 3 mm.

PURPOSE

This case report describes the successful management of GS of a young man.

CASE REPORT

The procedures were performed and these techniques resulted in shortened vestibule and restricted the muscle pull of the elevator muscles of the lip, reducing gingival display when the patient smiles. Surgical lip repositioning can be a minimally invasive alternative to orthognathic surgery. Botulinum Toxin injections can be a useful adjunct to enhance the esthetics and improve patient satisfaction, being a more conservative and immediate nonsurgical treatment modality available.

CONCLUSIONS

In this way, the clinical case report demonstrated that lip repositioning surgery combined to botulinum toxin injections promising outcomes in the GS correction. The effect showed a marked reduction in gingival display at the 4-years follow-up.

Ultrasound Imaging of the Facial Muscles and Relevance with Botulinum Toxin Injections: A Pictorial Essay and Narrative Review

High-resolution ultrasound is preferred as the first-line imaging modality for evaluation of superficial soft tissues, such as the facial muscles. In contrast to magnetic resonance imaging and computed tomography, which require specifically designated planes (axial, coronal and sagittal) for imaging, the ultrasound transducer can be navigated based on the alignment of facial muscles. Botulinum toxin injections are widely used in facial cosmetic procedures in recent times. Ultrasonography is recognized as a useful tool for pre-procedure localization of target muscles. In this pictorial review, we discuss the detailed sonoanatomy of facial muscles and their clinical relevance, particularly with regard to botulinum toxin injections. Furthermore, we have summarized the findings of clinical studies that report ultrasonographic imaging of facial muscles.

Analyses of Youtube Videos on Botox Treatment of Gummy Smile

OBJECTIVE

The purpose of this study was to determine the content quality and accuracy of the YouTube videos about the Botox application during gummy smile treatment and to analyze the efficacy of these videos in informing the healthcare professionals and the patients.

MATERIALS AND METHODS

The first 200 videos resulting from the search on YouTube by using the keywords "gummy smile/Botox," which were determined by Google Trends, were evaluated in the study. One hundred fourteen out of these 200 videos were included in the study. The videos were calculated using these descriptive features. A content scale consisting of 8 categories was used to determine the content levels of the videos and the video information and quality index scale was used to determine the quality level.

RESULTS

The most mentioned subjects in the videos were "Description" of the gummy smile and Botox treatment (71.9%), "Advantage" of Botox treatment (51.8%), "Procedure" (48.2%), and "Prognosis" (47.4%). The "Contraindication" was mentioned rarely (2.6%). A statistically significant difference was found between the videos with different content levels in terms of Description, Advantage, Indication, Procedure, Complication, Prognosis, and Cost. Likewise, there was a statistically significant difference between videos in distinct content level groups in terms of video information and quality index total score.

CONCLUSIONS

The quality of the YouTube videos about Botox applications in gummy smile treatment was found to be low in general. It is important for the physician who will perform the procedure to explain the procedure to the patients in detail. In addition, YouTube was determined to be insufficient for accessing high-quality information for students, assistants, and specialist physicians.

Comparison of Two Botulinum Toxin Injection Methods for Treatment of Excessive Gingival Display

BACKGROUND

Hyperfunction of the muscles of the upper lip is considered as the most common cause of excessive gingival display (EGD). The aim of this study was to demonstrate the effectiveness of botulinum toxin (BT) injection as a conservative treatment for EGD due to muscular hyperfunction and to compare the outcome of 2 injection methods.

MATERIAL AND METHODS

This study included 40 participants who were randomly assigned into 2 groups of 20 each, The first group received 2.5IU BT injection at 1 point per side (2-points group), while the second group received a total of 5 IU of BT at 2 points per side (4-points group). The outcome variables were the reduction in the central and lateral gingival display expressed as the difference between the pre- and post-injection measurements and the degree of satisfaction of the participants. The follow up visits were at 2- and 12-weeks postinjection. The study variables were statistically analyzed and probability values of <0.05 were considered significant.

RESULTS

There was a significant improvement (P < 0.0001) in both groups throughout the follow up period, but the improvement achieved by 4-points group was significantly better than that of the 2-points group with respect to the gingival display and the degree of satisfaction (P < 0.0001).

CONCLUSIONS

Botulinum toxin injection represents a safe and less invasive modality for treatment of EGD, the 4-points method results in better outcome in terms of clinical measurements and degree of satisfaction over the 2-points method.

Individual Factors of Botulinum Type A in Treatment of Gummy Smile: A Prospective Study

BACKGROUND

Botulinum type A (BTX-A) injection is a promising treatment for gummy smile (GS), although its effects are varied and inconsistent.

OBJECTIVES

The aim of this study was to explore the effect of individual factors on BTX-A treatment for GS, and to establish treatment expectations.

METHODS

In this prospective clinical study, a standardized technique comprising bilateral single-point injections of 2 U BTX-A (total, 4 U) was administered to all GS patients. Data were collected at baseline and after 4, 12, and 32 weeks of follow-up. Twenty-nine potential individual factors were analyzed by correlation and regression analysis to exclude confounding bias.

RESULTS

Ninety-four patients completed the BTX-A treatment. After adjusting for potential confounding factors, the correlation and regression analysis confirmed the following formula: anterior gingival exposure (GE) at 4 weeks = 1.44 + (0.94 × baseline anterior GE) - (1.88 × sex) (where male = 1 and female = 2). The confidence interval (CI) of the prediction showed that for all female participants with baseline anterior GE <5.3 mm, the 95% CI of anterior GE was 0.3 to 3.0 mm after 4 weeks of treatment, and 3.0 to 8.9 mm with baseline anterior GE ≥6 mm. For male patients with baseline anterior GEs of 3 and ≥4.6 mm, the 95% CIs were 1.5 to 3.3 mm and 3.2 to 8.9 mm, respectively.

CONCLUSIONS

The effect of average-dose BTX-A treatment for GS depended on GS severity and patient's sex, rather than GS etiology and other factors. Female participants with baseline anterior GE <5.3 mm were more likely to show complete improvement after 4 weeks of treatment. However, female participants with baseline anterior GE ≥6.0 mm or male participants were less likely to show complete improvement at 4 weeks.

LEVEL OF EVIDENCE: 4

Treatment of Excessive Gingival Display by Using Botulinum Toxin-A Targeting Yonsei Points and Zygomatic Major Muscles

ABSTRACT

The aim of this clinical report is to present satisfying and unsatisfying treatment results of a patient with excessive gingival display (EGD) treated via botulinum toxin injections in different time points. A 22-year-old male patient referred to the Department of Periodontology with a complaint of EGD. The patient opted the treatment with botulinum toxin-A injections. During the first treatment, injections at Yonsei points were performed. After the first EGD treatment, the patient did not satisfy with his smile. The closure of gingival display was not sufficient, especially in posteriors. However, he did not demand for reinjection. Six months after the first treatment, he was advised to have 2 injection points per side including zygomatic major muscles as well as Yonsei points. Two weeks after the second treatment, the patient totally satisfied with his new smile. Yonsei point is a safe and repeatable injection point for the practitioners. However, the authors suggested injections targeting zygomatic major muscles as well as Yonsei point injections to treat the patients with mixed EGD.

The effect of botulinum toxin A in patients with excessive gingival display with and without zinc supplementation: randomized clinical trial

OBJECTIVE

The objective is to determine the effect of oral zinc supplement intake on the clinical efficacy and sustained effect of BTXA injection, in patients with excessive gingival display (EGD).

MATERIALS AND METHODS

Twenty-five participants with excessive gingival display (EGD) were included in this parallel-group RCT, treated with BTXA with and without Zinc supplementation prior to treatment. Participants were assessed for excessive gingival display reduction and results of stability at 2, 6, 12, 18, and 24 weeks. Patient satisfaction questionnaires were filled at 2, 12, and 24 weeks.

RESULTS

The results of this study revealed that after 6, 12, 18, as well as 24 weeks; The control group (BTXA) showed statistically significantly higher median gingival display than the intervention (Zinc supplement with BTXA). In the intervention group, the median gingival display after 24 weeks showed statistically significantly lower median value compared to the baseline measurement CONCLUSIONS: The use of zinc supplementation prior to BTXA injection prolonged its effect and maintained long-term decreased amount of gingival display, and it did not return to baseline measurements. Patients reported high satisfaction levels and self-confidence.

CLINICAL RELEVANCE

Botulinum Toxin A (BTXA) is used to correct gummy smile; however, its main drawback is its short-lasting effect. Oral zinc supplement intake prior to BTXA injection could maintain the effect of BTXA and enhance its clinical efficacy.

Clinical and electromyographic evaluation of botulinum toxin type A in the treatment of gummy smile: A prospective clinical study

Background. The present study aimed to assess the effect of botulinum toxin type A (BTX-A) for the management of gummy smile and evaluate its stability after administrating BTX-A clinically and using electromyography. Methods. The investigators designed and implemented a prospective clinical study on 10 patients with a gummy smile. Patients with different types of gummy smile were injected with BTX-A in the levator muscles of the upper lip and were followed for six months. The effect of BTX-A was evaluated clinically and using electromyography preoperatively and after two weeks and three and six months. Statistical analyses were carried out using repeated measures ANOVA and post hoc Bonferroni tests for pairwise comparisons. Results. The sample consisted of 10 patients with an anterior gummy smile (n=3), posterior gummy smile (n=2), mixed gummy smile (n=3), and asymmetrical gummy smile (n=2). There were significant differences (P < 0.001) between the mean gingival display and compound muscle action potential at two-weeks and three-month follow-ups. The maximum result was obtained at the two-week interval. The mean gingival display and C-MAP values increased slightly at the three-month postoperative interval and gradually increased to the baseline values at six-month follow-up. Conclusion. BTX-A is an effective, minimally invasive, and temporary treatment modality for gummy smiles. The electromyographic study is a convenient method for assessing changes in the upper lip muscle contractility to quantify the effect of BTX-A in the treatment of gummy smile.

Management of excessive gingival display using botulinum toxin type A: a descriptive study

Botulinum toxin is a protease used by the bacterium Clostridium botulinum that causes chemical denervation of skeletal muscles, producing a temporary weakening of muscle activity. Despite having a transitory effect, the application of botulinum toxin has been identified as an alternative for correcting an excessive gingival display (EGD). However, studies evaluating the maintenance of long-term results of botulinum toxin remain scarce. This study aimed to evaluate the effectiveness and duration of botulinum toxin type A in the treatment of anterior EGD. Botulinum toxin Type A was applied to 15 patients with EGD. The measurement was performed in triplicate, using a Castro Viejo dry point compass, between the central cervical portion of the upper lateral incisors to the lower portion of the upper lip, bilaterally. The measurements were performed before the application of the toxin and repeated on days 7, 14, 90, 120, and 180 after the procedure. The data were analyzed using repeated-measures ANOVA, followed by a Bonferroni. There was a statistically significant reduction between the measurements performed on the Baseline and seven days after the application of the botulinum toxin. After 180 days, approximately one-quarter of the patients in the sample did not presented EGD. Mild adverse effects were reported by 46.7% of the patients. The use of botulinum toxin type A was effective to treat EGD. After 180 days, it was still possible to observe a significant effect compared to the initial gingival exposure.

Surgical Correction of the "Gummy Smile"

The delineation of excessive gingival display and review of current treatment options. Discussion over periodontal and prosthetic treatments, mucosal stripping procedures, myotomies, Botox therapy, and orthognathic procedures for correction of the "gummy smile."

Comparison of Botulinum Toxin and Orthognathic Surgery for Gummy Smile Correction

Objective:

This study aimed to compare the changes in the gummy smile in cases treated with botulinum toxin (BTX) application or orthognathic surgery.

Methods:

The retrospective sample comprised 61 subjects with gummy smile divided into 2 groups according to treatment received for gummy smile correction: 1-38 patients (6 male; 32 female), at a mean age of 28.60 years (s.d.=6.09), treated with BTX application; 2- 23 patients (7 males and 16 females) at a mean age of 29.59 years (s.d.=5.72) treated with orthognathic surgery. Patients from the BTX group refused to undergo orthognathic surgery. The measurement of the gingival exposure was performed in extraoral photographs of the posed smile, before and after treatment, and it was defined as the difference between the stomion of the upper lip and the incisal edge of the maxillary central incisor minus the height of maxillary central incisor obtained in the patient's dental casts. The data were obtained before (T1) and after treatment (T2) and change of gingival exposure with treatment (T2-T1). Intergroup comparison of gummy smile was performed with independent t-tests.

Results:

The surgical group presented significantly greater correction of the gummy smile with treatment than the BTX group.

Conclusion:

Gummy smile presented a greater improvement in patients treated with orthognathic surgery than with botulinum toxin application.

Effects of different doses of abobotulinumtoxinA for the treatment of anterior gingival smile

Botulinum toxin type A (BoNT-A) is an easy and fast treatment for gingival smile (GS). The objective of the study was to compare the reduction of gingival exposure using three different doses of abobotulinumtoxinA (ABO) in patients with different severities of anterior GS, and to assess treatment safety and patients' satisfaction. A prospective, single-center, randomized, double-blind study was conducted. Mild GS (2 to < 3 mm) was treated with 2.5 U of abobotulinumtoxinA (ABO) per side, moderate GS (3 to < 4 mm) with 5 U of ABO per side, and severe GS (4 mm or more) with either 2.5 U, or 5 U or 7.5 U of ABO per side. All the 41 enrolled patients completed the study. The mean gingival exposure reduced significantly 4 and 12 weeks after treatment. The average reduction of gingival exposure with 5 U was significantly larger than that obtained with 2.5 U, (3.46 ± 1.39 vs. 2.05 ± 1.29 mm; p = 0.004). All groups of GS severity presented statistically significant reduction in the gingival exposure 4 and 12 weeks after ABO injections. Twelve weeks after treatment, more than 80% of the patients were satisfied or very satisfied. There were no treatment-related adverse events reported by the patients or noticed by the investigators. Gingival smile can be safely and effectively managed with BoNT-A injections and specifically with ABO injections to target the LLSAN muscle. Further and larger studies may determine the exact influence of each factor on BoNT-A treatments of GS.

The maxillary incisor display at rest: analysis of the underlying components

Introduction:

Maxillary incisal display is one of the most important attributes of smile esthetics.

Objective:

The aim of this study was to determine the relationship between maxillary incisal display at rest (MIDR) and various soft tissue, hard tissue and dental components.

Methods:

A cross-sectional study was conducted on 150 subjects (75 males, 75 females) aged 18-30 years. The MIDR was recorded from the pretreatment orthodontic records. The following parameters were assessed on lateral cephalograms: ANB angle, mandibular plane angle, palatal plane angle, lower anterior and total anterior facial heights, upper incisor inclination, upper anterior dentoalveolar height, and upper lip length, thickness and protrusion. The relationship between MIDR and various skeletal, dental and soft tissue components was assessed using linear regression analyses.

Results:

The mean MIDR was significantly greater in females than males (p = 0.011). A significant positive correlation was found between MIDR and ANB angle, mandibular plane angle and lower anterior facial height. A significant negative correlation was found between MIDR and upper lip length and thickness. Linear regression analysis showed that upper lip length was the strongest predictor of MIDR, explaining 29.7% of variance in MIDR. A multiple linear regression model based on mandibular plane angle, lower anterior facial height, upper lip length and upper lip thickness explained about 63.4% of variance in MIDR.

Conclusions:

Incisal display at rest was generally greater in females than males. Multiple factors play a role in determining MIDR, nevertheless upper lip length was found to be the strongest predictor of variations in MIDR.

Gummy Smile Treatment: Proposal for a Novel Corrective Technique and a Review of the Literature

Background

A perfect smile is dictated by the balance among 3 parameters: the white (teeth), the pink (gum), and the lips: excessive gingival display while smiling has been a cause of esthetic embarrassment for many patients, thus affecting their psychosocial behavior. With respect to different etiologies, treatment of gummy smile must be properly planned: treatment options include facial surgery, oral surgery, or laser.

Objectives

Given the growing demand for less invasive techniques and observed complications secondary to botulinum toxin injection, we present a novel treatment option aimed at correcting gummy smile using hyaluronic acid injection and review the published techniques and the anatomy of the involved facial muscles.

Methods

The treatment was performed by infiltration in the paranasal area, in the location of the most cranial portion of the nasojugal fold, about 3 mm lateral to the alar cartilage wing, according to a vector perpendicular to the cutaneous plane, to gently compress the lateral fibers of the levator labii superioris alaeque nasi without invading it. A Vycross® technology filler was used for all the treatments.

Results

All patients had an immediate improvement, with a maximum duration ranging from 186 to 240 days (mean, 213 days), according to parameters of the Global Aesthetic Improvement Scale (GAIS 4.06).

Conclusions

This new, less invasive and safer technique to correct dynamic excessive gingival display was shown to be feasible and safe with a long-lasting result. This treatment could be a novel effective option for experienced injectors to treat aesthetic facial flaws.

Level of Evidence 4

Micro-Autologous Fat Transplantation for Treating a Gummy Smile

Background

A gummy smile is treated using many techniques, including botulinum toxin injection and various surgical interventions. Micro-autologous fat transplantation (MAFT) is a potentially advantageous alternative approach that has not been previously evaluated.

Objectives

This study sought to determine the long-term results of MAFT in patients with a gummy smile.

Methods

Seven patients with gummy smiles were evaluated for MAFT treatment between October 2015 and April 2017. Centrifuged purified fat was micro-transplanted into the nasolabial groove, ergotrid, and upper lip areas using the MAFT-GUN while the patients were under total intravenous anesthesia.

Results

The mean age of the 7 patients was 31 years (range, 23-40 years). The mean operating time for MAFT was 52 minutes (range, 40-72 minutes), and the mean volume of fat delivered to the nasolabial groove, ergotrid, and upper lip was 16.1 mL. The mean decreases of gingival display in the right canine incisor, left canine incisor, right canine, and left canine teeth were 4.9, 4.6, 3.8, and 4.4 mm, respectively. The smiles of the 7 patients showed significant improvement at an average follow-up time of 12.9 months.

Conclusions

Gummy smile treatment using MAFT is an effective, reliable, and relatively simple method, with high patient satisfaction and minimal risk of complications.

Level of Evidence: 4

The Use of Neurotoxins in the Male Face

Injection of neurotoxin is the most commonly performed cosmetic procedure in the United States, and the total number of male patients seeking botulinum has steadily increased over the years. Because of their unique aesthetic goals, expectations, and anatomy, men require differing botulinum toxin doses and techniques. This article provides an evidence-based approach to botulinum toxin in men. Each area of the face is discussed separately, focusing on gender differences in anatomy, treatment goals, and injection method.

Duration of effectiveness of Botulinum toxin type A in excessive gingival display: a systematic review and meta-analysis

Botulinum toxin type A is effective in reducing excessive gingival display caused by hyperfunctional upper lip elevator muscles; however, this effect is transient. This study aimed to determine the duration of the effectiveness of botulinum toxin type A on a gummy smile. A systematic search was conducted using Medline (PubMed), Scopus, and Web of Science electronic databases, from 1970 to March 2017 with no language restriction; the search included studies evaluating adult patients with excessive gingival display who were treated with botulinum toxin and were followed-up for at least 3 months. OpenGrey and Clinical Trial Registry were also consulted. Quality assessment was applied to determine the level of evidence and bias, and a meta-analysis was performed. Of 2181 full texts, 71 were obtained, with 3 prospective studies meeting the selection criteria. The gingival display was significantly reduced to baseline with 2, 4, and 8 weeks of treatment. The gingival display considerably reduced at the baseline-2-week comparison (-4.44 mm using raw data and-4.05 mm using the standard difference) and increased throughout the weeks of follow-up. There is scant evidence to determine the duration of the effectiveness of toxin type A on a gummy smile. The effect tends to be stable until at least 8 weeks of follow-up, and the gingival exposure may not return to baseline within 12 weeks of follow-up. Well-designed randomized clinical trials with a minimum of 6 months of follow-up are necessary to strengthen the evidence.

Aesthetic perception of gingival smiles

Abstract Introduction Dentists have shown interest in learning new techniques to create more attractive smiles, but with little concern for understanding the reasons why the patient is dissatisfied. Objective To evaluate the aesthetic perception of laypersons in dentistry in comparison with general practitioner dentists and periodontists regarding the gingival smile, and to compare this aesthetic perception between the male and female genders. Methodology A photograph of a standard smile was taken and was digitally modified to create the periodontal conditions of a gingival smile from 0.5 mm to 2.5 mm. The photographs were judged by 150 individuals (25-65 years of age), 81 female and 69 male, divided into three groups: 50 laypersons, 50 general practitioners and 50 periodontists. The evaluation was performed using a visual analog scale. The statistical evaluation tests used were the Pearson Chi squared test, Student's t-test, ANOVA and Newman-keuls. Result The aesthetic perceptions among the professionals are similar, and they observe more subtle changes in the aesthetics of the smile than the laypersons observe. The general practitioners and periodontists were similarly sensitive to changes generated in the gingival smile when these reached 1.5 mm, while laypersons only perceived them when these changes reached 2.5 mm. There was no significant difference in the aesthetic perception of male and female evaluators in any of the groups. Conclusion The aesthetic perception of the gingival smile between general practitioner dentists and periodontists was similar, and dental professionals were more demanding than the layperson. There was no difference between female and male aesthetic perceptions.

A successful management of sever gummy smile using gingivectomy and botulinum toxin injection: A case report

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Botox injections considered as an alternative treatment for sever gummy smile.

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Extensive surgical procedures can be avoided in treatment of gummy smile by using Botox injections.

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The gingivectomy and Botox injections exhibited satisfactory results for the functional and esthetic rehabilitation of the gummy smile

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The combination of crown lengthening procedures and Botox injections give satisfactory results for gummy smile patients.

Introduction

A gummy smile (GS) affects the esthetic and the psychological status as it usually decreases the self-confidence leading to hidden or controlling the smile. A smile with more than 2 mm exposed gingiva is called gummy smile. It may be due to one or more of the following etiologies; altered passive eruption of teeth, dentoalveolar extrusion, vertical maxillary excess, and short or hyperactive lip muscles. The treatment of gummy smile should be planned according to its cause/causes. The purpose of this case report was to highlight the ability of combined treatment of gingivectomy and Botox injection technique in managing a severe gummy smile. Also, techniques, advantages, disadvantages, indication and contraindications of Botulinum toxin (BT) are discussed at the literacy.

Presentation of the case

A 24 year old female patient with a severe gummy smile was refereed to the periodontal clinics of our institution. Clinical examination revealed that she has a GS of an 11–12 mm gingival exposed area that was indicated for orthognathic surgery. The GS was treated by a gingivectomy surgery to increase the clinical crowns of upper anterior teeth and the use of Botox injections. The treatment showed remarkable and satisfactory results instead of doing extensive surgery.

Discussion and conclusion

It is important to assess the patients’ esthetic expectations and show the possible therapeutic solutions that fit him. We revealed that BT is considered as one of the minimally invasive, quick and affordable modalities that can replace extensive surgical procedures for corrections of sever GS.

The Practical Use of AbobotulinumtoxinA in Aesthetics

Botulinum toxin (BoNT) has been approved for aesthetic use since 2002. Since then, clinical studies and expert use have informed our understanding of how BoNT exerts its clinical effect and the practical use of this product across a number of aesthetic applications. This review discusses the clinical properties and characteristics of abobotulinumtoxinA, which patients are suitable for its use, and how it can be utilized to treat facial rhytides.