Efficacy of combining clinical crown lengthening surgery and botulinum toxin A injection in gummy smile treatment

Introduction: A gummy smile is usually seen when gingival exposure more than 3 mm is visible. Esthetic crown lengthening may include a variety of surgical techniques for the gummy smile treatment, all of which aim to improve the esthetic appearance of teeth and gingiva. Crown lengthening is a surgical procedure aimed at removal of periodontal tissue to increase the clinical crown height.Case: A 21-year-old woman was referred to the Prof. Soedomo Dental Hospital. The patient presented good general health and anterior maxillary teeth with short clinical crowns. There was no periapical radiolucency at radiographic. Gingival exposure was 6 mm. Preoperative intraoral examination showed healthy gingiva, and the clinical crown ratio was about 1:1. At clinical examination, periodontal pocket depth was 3 mm or less, and bone sounding was 3.5 mm or less. After determining the problem, esthetic crown lengthening surgery was performed under local anesthesia. Chu’s aesthetic gauge ratio used to measure ideal clinical crown ratio allowed gingivectomy. Mucoperiosteal flap raised after incision followed by ostectomy to maintain biological width. The flap was repositioned and sutured with various suture technique. Frenototomy was performed to release flap tension, and periodontal dressing was applied after frenotomy. Intraoral examination in 3 months follow up showed reduced gingival exposure to 3 mm and ideal clinical crown ratio.Conclusion: The esthetic crown lengthening with ostectomy and frenotomy for treatment of gummy smile was successful to reduced gummy smile and reach ideal clinical crown ratio.

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.

The aim of this systematic review is to synthesize the evidence on the effectiveness and longevity of the botulinum toxin in the treatment of individuals with excessive gingival exposure. The search was adapted to six electronic databases and gray literature. The risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool for Non-Randomized and Randomized Studies of Interventions. Meta-analyses and meta-regression were performed using random effects models. A total of 5247 articles were collected during the final search in the database, resulting in 17 articles included. There was a mean decrease of 3.42 mm [95% CI = -4.50 to -2.34; I2 = 97%] in the level of gingival exposure 2 weeks after the application of botulinum toxin. The application time explained 29.58% of the observed variance (p < 0.001), with a tendency for the effect size to decrease from the second week of application onwards, with values returning close to baseline levels in 24 weeks. Botulinum toxin is an alternative technique considered effective for reducing gummy smile, especially for gummy smiles up to 4 mm, with a longevity of at least 12 weeks, returning close to initial values within 24 weeks after application. The knowledge about the longevity and effectiveness of botulinum toxin in the treatment of gummy smile allows for a more adequate clinical planning for these cases, as well as for clinical decisions, as for prognostic factors.

Botulinum toxin for gummy smile correction

The treatment of gummy smile (GS) with polymethyl methacrylate (PMMA)-based implants is suggested in specific cases such as those in which there is a lack of lip support due to a marked depression of the anterior maxillary process; however, it can be associated with certain complications related to the material and the surgical approach. A patient with a GS of combined etiology was treated with clinical crown lengthening and lip repositioning surgery with placement of a PMMA-based bone cement implant to fill the subnasal depression. Surgical planning was performed using a 3-dimension resin-printed model to achieve an optimal fit of the PMMA implant to the geometry of the bone defect and to avoid any damage related to heat exposure from the polymerization process and any possible damage to the tooth roots with the fixation screws. In addition, the use of an antibiotic cement can help prevent any possible infection. The patient reported edema and mild pain. After 5 months an increase in the length of the dental crowns, a reduction of the exposed gingiva to 1mm and a new support of the upper lip were clinically observed. Cone-beam computed tomography showed proper PMMA implant fit. The use of PMMA-based bone cement appears to be an effective technique for the treatment of cases of GS associated with hypermobile upper lip and maxillary subnasal depression. The use of a printed resin model avoids complications during curing of the material, such as high exothermic reactions and associated infections. Identification of the etiologic factors of gummy smile is fundamental to the treatment of gummy smile. Once the diagnosis is established, therapy focuses on the treatment of these factors, which may be single or combined. The use of a PMMA-based bone cement implant in conjunction with clinical crown lengthening surgery is an effective treatment option for the management of EGD related to upper lip hypermobility, passive altered eruption and, maxillary subnasal depression. A possible clinical dilemma could arise when considering some complications associated with the use of PMMA implants such as allergies or infections. However, the use of a 3D printed resin model facilitates handling and fitting outside the mouth by eliminating heat exposure from the polymerization of the cement and to avoid any possible damage to the tooth roots with the fixation screws. In addition, the use of an antibiotic cement can help prevent any possible infection. The treatment of gummy smile will depend on its etiological factor. In some cases of combined etiology, the use of polymethyl methacrylate (PMMA) implants has been suggested, such as those in which there is a lack of lip support due to a marked depression of the maxillary anterior process; however, the use of PMMA can be associated with certain complications such as allergies and infections. To avoid this, surgical planning was performed using a 3D resin-printed model to achieve an optimal fit of the PMMA implant to the geometry of the bone defect and to avoid any complications such as damage related to the heat exposure of the polymerization process and any possible damage to the dental roots with the fixation screws, obtaining satisfactory results after 5 months.

The report about growth and development, calcification and eruption year of teeth had been made and published by many investigators but mutual relation between teeth and paradentium was not understood accurately.Upper and lower central incisors had been continuously observed for 17.5 months (upper 48 samples, lower 11 samples) by contrast radiography, originally, developed for the purpose.Clinical teeth crown length before and after dental completion is measured and change from clinical dental crown length to anatomical crown length after dental emergence was observed in 526 samples (upper 279, lower 247) in association with continuous observation groups.Obtained results were as follows :1. Rider was set on the cutting-edge of incisor and labial surface of dental crown and gingival boundary line were plastered with contrast medium. Approximately value of clinical dental crown length and teeth length from radiography were found.2. When the teeth in jaw attained three-quarters of completed teeth length, their eruption was found in oral cavity.3. Judging from continuous observation groups, growth velocity of clinical dental crown length and teeth length in upper or lower jaws fast, 4 or 5 months after eruption but slower late after its time.4. Clinical dental crown length attained one-half of anatomical crown length in upper jaw about a year after emergence and in lower jaw about a year and 2.5 months.5. From the result of statistical analysis, the developmental relation between clinical dental crown length and teeth length was of high correlation.(r=0.97, Y=-15.92 + 0.94 X, in upper; r =0.98, Y=-11.014-0.76 X, in lower)6. Judging from continuous observation groups and other observation groups, the root was complet 27.17 months in upper and 30.93 months in lower after emergence.7. Clinical dental crown length was in upper about 60.9 % and in lower about 58 % of anatomical crown length at the time of root completion.8. After root completion, clinical dental crown length was linear in semi-logarithmic table. Clinical dental crown length increased in propotion to a logarithm of months.9. Clinical dental crown length was in accord with anatomical crown length in upper 822 months (approximately 69 years) and in lower 619 months ( approximately 52 years) after emergence.

Excessive gingival exposure (gummy smile) is a non-aesthetic condition characterized by excessive exposure of the gingiva during smiling. The most common cause of gummy smiles was reported to be the hyperfunction of the muscles of the upper lip. Previous reports showed that botulinum toxin (Botox) is effective in the treatment of gummy smiles with a reversible effect, rapid initial action, safe application, low risk, and satisfactory outcome. The effect of Botox is usually observed between one and two weeks. This study aims to review the recent updates and guidelines for gummy smile treatment using botulinum toxin. A literature review was conducted involving relevant studies discussing gummy smile treatment using botulinum toxin with no time restriction. The PubMed and Google Scholar databases were used to gather the most relevant studies. The initial screening revealed 62 studies, and after removing the out-of-scope studies, the final review included 28 studies. Botulinum toxin can be used effectively for the treatment of gummy smile caused by lip dynamics with rarely reported complications. However, the most observed limitation was the temporary duration, which was reported to range from four to six months, and the re-injection of botulinum toxin is usually needed.

Treatment of gummy smile: Nasal septum dysplasia as etiologic factor and therapeutic target

The gummy smile is characterized by a marked gingival exposure on smiling and it has been considered as one of the main complaints of patients, also influencing on self-esteem and social relationship. The development of new techniques such as botulinum toxin application may be a more conservative treatment option than surgical intervention (myectomy and Le Fort I osteotomy) in the treatment of gummy smile. Objective: To present the case of a patient who presented dental-gingival discrepancy and gummy smile, treated by gingival resection surgery and complemented by the application of botulinum toxin. Case report: A female patient, 23 years old, presented dental-gingival discrepancy and gummy smile, treated by gingival resection surgery and complemented by the application of botulinum toxin. Results: The gingival resection surgery promoted improvement of dental relationship, caused by increase of dental zenith and the application of botulinum toxin caused uniform dehiscence of the upper lip, increasing the harmony of the smile and improving self-esteem and quality life. Conclusion: Botulinum toxin is an additional option in the cosmetic improvement of the smile and gives better results when combined with gingival resection surgery.

BackgroundThe mechanism of force application in clear aligner treatment involves wrapping the clinical crowns, suggesting that the size of the clinical crowns may impact tooth movement. The present finite element study aimed to explore the impact of clinical crown length on the sagittal movement of maxillary central incisor in clear aligner treatment.MethodsThe standard maxillary dentition model was developed using computer tomography scanning. Finite element models of the maxillary dentition, alveolar bone, periodontal ligament, and aligners were established. Twelve model groups were divided based on different clinical crown lengths and attachments’ position to simulated the tipping and translational movements of the right maxillary central incisor. The dimensions of the short and long clinical crowns were determined based on epidemiological evidence, and appropriate models were constructed by shortening or elongating the normal incisors by 20% along the longitudinal axis of the tooth. Horizontal rectangular attachments were constructed at the clinical crown center of the short, normal and long clinical crowns. These attachments were categorized into four types: no attachment, labial attachment, palatal attachment and labio-palatal attachments. The finite element analysis focused on evaluating the contact pressure distribution on the crown, displacements, rotations, and von Mises stress in PDL of the right maxillary central incisors.ResultsIn tipping movement, the long clinical crown exhibited the highest crown displacement and rotation, enhancing the efficiency. In translational movement, the long clinical crown had the lowest TL/CD value, losing less torque during the crown displacement. However, the short clinical crown had the lowest Mx/Fy value, with a greater tendency to move bodily rather than long ones. The von Mises stress distribution in PDL was similar between the two types of movement, while the maximum von Mises stress increased with increasing clinical crown lengths in tipping movement. Labio-lingual attachment had the optimal effect in tipping and translational movement.ConclusionsClinical crown length has considerable influences on the efficiency, movement behavior, and maximum von Mises stress of the PDL in the sagittal movement of maxillary center incisor in clear aligner treatment. Moreover, attachments also influence the movement efficiency of the incisor.

Evaluation of the internal dual muscle traction approach as an adjunct to the modified surgical lip repositioning method: A randomized clinical report

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

Background: The pursuit of esthetic excellence has become a major goal in the dental treatment. Gummy smile is one of the complaints of the patients, since such a situation can influence self-esteem and social relationships. The beauty of the smile is not only constituted by the shape, position and size of the teeth, but also based on the characteristics of the gingival tissue and conformation of the lips, which should be as harmonious as teeth. The development of new more conservative techniques may provide a better therapeutic option than surgical procedures, such as the application of botulinum toxin, in the treatment of gummy smile. Purpose: to present the case of a patient who presented dentogingival discrepancy caused by gingival overgrowth and gummy smile, treated by gingivoplasty and complemented by application of botulinum toxin. Description of the case: The gingivoplasty was performed followed by the application of botulinum toxin type A. Results: The gingivoplasty resulted of the improvement of gingival arches and the application of botulinum toxin promoted the dehiscence of upper lip, reducing the gingival exposure. Conclusions: The application of botulinum toxin, associated with gingivoplasty, is an important tool at the management of gummy smile, optimizing smile harmony and achieving improved self-esteem and quality of life.

ABSTRACTAim:This study aimed to compare the effectiveness, duration, and patient satisfaction of botulinum toxin A (BTX-A) and hyaluronic fillers in treating gummy smiles.Materials and Method:A prospective clinical study was conducted at D.Y. Patil University, involving 14 patients aged 18–40 years with a gummy smile of ≥3 mm. Participants were divided into two groups: Group A (BTX-A injections) and Group B (hyaluronic fillers). Gingival display was measured using standardized photographic methods at baseline and follow-up visits (14, 30, 60, and 90 days). Patient satisfaction was evaluated using the Global Aesthetic Improvement Scale (GAIS).Result:The results indicated that while BTX-A provided immediate improvements, hyaluronic fillers demonstrated more consistent and prolonged results. Patient satisfaction was higher in the hyaluronic filler group, with most patients reporting exceptional improvement (GAIS score of 1) across all follow-ups. No severe adverse effects were observed in either group.Conclusion:Hyaluronic fillers demonstrate superior effectiveness and patient satisfaction compared to BTX-A in the treatment of gummy smiles.

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.