Clinical and radiographic assessment of gummy smile patients with altered passive eruption: a cross-sectional study in a Thai population.

OBJECTIVES: The study aimed to evaluate the clinical crown length (CCL) among patients diagnosed with altered passive eruption (APE), the causes of a gummy smile, the prevalence of APE, and the correlation between parameters. MATERIALS AND METHODS: A total of 86 gummy smile patients (516 teeth) underwent clinical examination and assessment using cone-beam computed tomography (CBCT), photography, and intraoral scanning. RESULTS: Significantly shorter CCL and distance between the cementoenamel junction and bone crest (CEJ-BC) were observed among APE-affected teeth (p < 0.05). Among the patients, 56.1% of patients were diagnosed with APE, and most of them were affected by a combination of APE and hypermobile upper lip (HUL). Based on 183 APE-affected teeth, the prevalence of APE types and subtypes was as follows: APE1A (96; 19.3%), APE1B (78; 15.9%), APE2A (8; 1.6%), and APE2B (1; 0.2%). Positive correlations were found between keratinized gingival width (KGW) and bone thickness (BT), while negative correlations were observed between gingival thickness (GT) and BT. CONCLUSION: Shorter CCL and CEJ-BC were the highlighted features of APE. APE affected approximately half of the gummy smile patients, with most of them presenting with a combination of HUL. Almost teeth affected by APE were classified as Type I, with a nearly equal distribution between subtypes A and B. CLINICAL RELEVANCE: The clinical and radiographic features of APE contribute to a better understanding of this condition and facilitate the management of patients affected by APE. Approximately half of gummy smile patients will require multidisciplinary treatment.

The Scalloped Surgical Guide as an Alternative to Flat Bone Reduction Guide in Full-Arch Implant Restoration.

The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery.

Treatment of excessive gingival display using conventional esthetic crown lengthening versus computer guided esthetic crown lengthening: (a randomized clinical trial).

BACKGROUND: Surgical guides have been proposed in an attempt to reach more predictable outcomes for esthetic crown lengthening. The objective of the present study was to evaluate the effectiveness of esthetic crown lengthening using 3D-printed surgical guides in the management of excessive gingival display due to altered passive eruption type 1B. MATERIALS AND METHODS: Sixteen patients diagnosed with altered passive eruption type 1B, were divided into two groups. In the control group, the procedure was carried out conventionally, and in the study group, a dual surgical guide was used. The parameters of wound healing (swelling, color, probing depth, bleeding index, and plaque index), pain scores, gingival margin stability, and operating time were assessed at 1 week, 2 weeks, 3 months, and 6 months postoperatively. RESULTS: There was no statistically significant difference in terms of wound healing, pain scores, and gingival margin stability between both groups at different time intervals (P = 1), however, there was a statistical difference between both groups in terms of operating time with the study group being significantly lower (P < 0.001). CONCLUSION: Digitally assisted esthetic crown lengthening helps shorten the operating time and reduces the possibility of human errors during the measurements. This will be useful in helping practitioners achieve better results. PRACTICAL IMPLICATIONS: The conventional method remains to be the gold standard. However, shorter operating time and lower margins for errors will help reduce costs as the chair side time is reduced as well as the possibility for a second surgery is lower. This will improve patient satisfaction as well.

Multifunctional anatomical prototypes (MAPs): Treatment of excessive gingival display due to altered passive eruption.

OBJECTIVE: To describe a strategy using digital technologies for improving the diagnosis, treatment planning, and surgical execution of patients with excessive gingival display (EGD) due to altered passive eruption (APE). CLINICAL CONSIDERATIONS: An important component for successful patient's management is to fulfill their esthetic expectations whilst delivering predictable and long-term therapeutic outcomes. To achieve this goal in patients with excessive gingival display due to altered passive eruption, it is essential to perform an accurate diagnosis and to communicate to the patient the expected customized results using digital technologies. Computer-aided designed and manufactured multifunctional anatomical prototypes (MAPs) may contribute to these purposes. Additionally, they can guide the surgical crown lengthening procedure or serve as a reference during the surgical guide fabrication providing information of the required anatomical landmarks. CONCLUSIONS: This novel strategy protocol for diagnosis, communication, and treatment management of patients with excessive gingival display follows functional and biological principles within the frame of a digital workflow, which improves the diagnostic capabilities, enhances communication, and guides the surgical treatment as shown in the 12 months follow-up of the reported case. CLINICAL SIGNIFICANCE: Developing a virtual patient by combining multiple digital data sets including cone-beam computed tomography (CBCT), intra-oral scans and digital photography, supports the clinician and the patient to achieve a comprehensive diagnosis and to better communicate the expected results to the patient. Furthermore, this digital treatment exercise based on anatomical and biological principles will facilitate the surgical precision and the achievement of successful outcomes, thus fulfilling the patient needs and expectations.

Clinical advantages of improving the excessive gingival display (EGD) by surgical repositioning of the upper lip.

OBJECTIVES: The objective of this study is to minimize gingival display by surgical repositioning of the upper lip and to suggest this technique as an alternative treatment modality to orthognatic surgery for treatment of excessive gingival display. MATERIALS AND METHODS: Forty-eight patients were selected with gingival display of more than 2 mm during maximal smiling. All patients underwent surgical repositioning of the upper lip, aimed at limiting elevator muscle activity to treat excessive gum exposure. Patients were regathered in 1 week for the follow-up postoperative symptoms according to VAS scale to evaluate pain and swelling. Reference values were given to patients. RESULTS: The study has indicated good results and stability especially to patients with skeletal class I classification along with medium and thick biotype of attached gingiva without hypermobile upper lip. CONCLUSION: Surgical repositioning of the upper lip is an effective way to improve a patient's gingival smile caused by degree I and II VME in combination with HUL as an alternative treatment modality to orthognathic surgery. This method is less invasive and cost-effective, causes minimal postoperative complications, and provides faster recovery. CLINICAL RELEVANCE: Excessive gingival display (EGD) with various etiologies requires several proper treatment modalities. The proposed modified method of lip repositioning to reduce the degree of gingival display is less aggressive, reliable, and causes fewer postoperative complications compared to orthognathic surgery.

Clinical efficacy of lip repositioning technique and its modifications for the treatment of gummy smile: systematic review and meta-analysis.

OBJECTIVE: To systematically review the literature regarding the clinical efficacy of reducing excessive gingival display (EGD) using the surgical lip repositioning technique (LRT) and its modifications. The question to address was: "What is the clinical efficacy of the surgical LRT and its modifications in patients with EGD?" MATERIAL AND METHODS: Four databases (MEDLINE-PubMed, Scopus, EMBASE, and CENTRAL) were searched up to December 2021 (PROSPERO-CRD42020205987). Randomized, non-randomized controlled and prospective case series with a minimum of 6-month follow-up were eligible for inclusion. Two meta-analyses were performed using the mean difference (MD) between baseline and different follow-up periods (6 and 12 months). Subgroup analyses were performed using the different modifications of LRT. RESULTS: The electronic research retrieved 783 studies. Only 13 met the inclusion criteria and were included in the statistical analysis. Six modifications of the original LRT were identified. An overall EGD reduction of -3.06 mm (95%CI: -3.71-2.40), -2.91 mm; (95%CI: -3.66-2.15) and -2.76 mm; (95%CI: -3.83--1.70) was achieved after 6, 12, and 36 months, respectively, compared to baseline (P < 0.01). Meta-analysis revealed that the use of LRT with periosteal suturing showed the greatest decrease in EGD with 5.22 mm (95% CI: 4.23-6.21; P < 0.01) at 6 months and 4.94 mm (95% CI: 3.86-6.02; P < 0.01) at 12 months. CONCLUSIONS: Both the original LRT and its different modifications reduce EGD and provide good results and overall patient satisfaction at 6, 12, and 36 months of follow-up. CLINICAL RELEVANCE: Evaluating the different modifications of the LRT can be a guiding aspect for the clinical and surgical approach to be used in patients with EGD.

Effect and longevity of botulinum toxin in the treatment of gummy smile: a meta-analysis and meta-regression.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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. CLINICAL RELEVANCE: 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.

Treatment of Dental Class-II, Division 2 Malocclusion Associated with a Deep Anterior Overbite: A Case Report Orthodontic Camouflage.

AIM: This study sought to correct the assessment of orthodontic camouflage treatment to provide a harmonized soft-tissue profile, consistent occlusion, and a pleasant smile. BACKGROUND: Class-II, division 2 malocclusions can be treated through dental compensation and growth modification methods instead of surgical-orthodontic treatment, which can be determined by the growth and age of the patient. CASE DESCRIPTION: This case report was of a 14-year-old Chinese female whose chief complaint was crowding of anterior teeth and required treatment for the same. On necessary clinical and radiographical examination, diagnosis of convex facial profile with class-II, division 2 malocclusion was arrived and hence treated with orthodontic camouflage. On treatment completion of 33 months, cephalometric assessment revealed that the anterior maxillary teeth had been successfully intruded and substantially distalized, with a slight counterclockwise rotation of the mandible. The treatment results and profile changes were demonstrated with good patient cooperation. CONCLUSION: Using a utility arch with orthodontic camouflage treatment can help to reinforce molar anchoring and improve a deep bite in the maxillary dentitions. The patient was treated with the devised treatment plan and acceptable results were obtained with patient satisfaction as recorded after 1 year of follow-up. CLINICAL SIGNIFICANCE: To correct a maxillomandibular discrepancy, an orthodontist may conduct a process known as camouflage therapy without necessity of surgery. However, patient selection forms a crucial role, and hence systematic arrival of the diagnosis and treatment protocol is a pivotal factor.

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.

Gummy Smile: Mercado-Rosso Classification System and Dynamic Restructuring with Hyaluronic Acid.

BACKGROUND: Gummy smile (GS) is a nonpathological condition causing esthetic disharmony in which an excessive amount of gingival tissue is exposed when smiling. Nowadays, there is not unanimous agreement regarding both classification and management of GS. This study aimed to present an organized and comprehensive clinical classification of the GS, as well as to discuss a therapeutic approach, with hyaluronic acid dermal fillers. METHODS: This study is presenting the clinical experience of the authors regarding GS. RESULTS: The Mercado-Rosso GS classification has into account aesthetic aspects, etiopathogenetic criteria, and functional aspects of the smile. According to Mercado-Rosso GS-classification-system, GS is divided into 3-types: Type 1, characterized by a lack of support and/or a lack of projection of the upper maxilla; Type 2, due to an imbalance between the strength (excess) and the resistance (defect) of the levator muscles; and Type 3, defined by an excessive strength of the zygomatic muscles, which causes a wide smile and an excessive visualization of the molar teeth. CONCLUSIONS: The Mercado-Rosso GS classification system is a tool that facilitates the diagnostic and therapeutic approach to the gummy smile. RD Dynamic Restructuring® constitutes a comprehensive therapeutic approach that makes reference to both the effect of the HA filler on the muscle movement and the balance between the muscle strength and the resistance of the soft tissue to be folded in different facial structures). LEVEL OF EVIDENCE: Level V.

Management of gummy smile using botulinum toxin: a case series.

A "gummy smile," considered to be exposure of more than 3.0 mm of gingival tissue during a forced smile, negatively affects smile esthetics. The present case series describes the clinical indications and technique for applying botulinum neurotoxin type A (BoNTA) to correct a gummy smile and assesses the outcomes and satisfaction levels of 3 patients. The patients were told about the risks and benefits of the procedure and advised that their gummy smile was likely to recur within 6 months posttreatment. After the exposed gingival tissue of the patients was measured with a ruler, photographs were taken, and the patients recorded their pretreatment level of satisfaction with their smile on a visual analog scale (VAS), the patients were treated with BoNTA. The BoNTA was diluted in 1 mL of sterile saline according to the manufacturer's instructions, and an extraoral point of application was marked 1 mm lateral to each of the patient's nasal wings, close to the insertion of the elevator muscles of the upper lip and the nasal wings. At each location, 4 U was injected by tilting the syringe 45° in relation to the skin. Fourteen days after treatment, the gingival tissue exposed during a smile was again measured with a ruler, new photographic records were taken, and the patients' level of satisfaction with the treatment and the esthetic result was determined. Repositioning of the upper lip was observed in all patients. No adverse effects or complaints were reported. All 3 patients reported that they were satisfied with the outcome and wanted to continue therapy with BoNTA as needed. The results of the reported cases suggest that the application of BoNTA constitutes a safe, effective treatment for the correction of gummy smile and is well accepted by patients. However, for the treatment to be successful, it is essential that clinicians master the facial topographic anatomy and the technique to be employed.

Efficacy of Infrazygomatic Crest Implants for Full-arch Distalization of Maxilla and Reduction of Gummy Smile in Class II Malocclusion.

AIM: The purpose of the study was to evaluate the efficacy of infrazygomatic (IZ) implants along with mini-implants for full-arch distalization of maxilla and reduction of gummy smile in patients with class II division I malocclusion. MATERIALS AND METHODS: Ten orthodontic patients were taken from the department of orthodontics and dentofacial orthopedics. Each patient required distalization and intrusion of the complete maxillary arch as a part of the treatment plan. Patients were of class II malocclusion with gummy smile. Initial leveling and alignment were done by using 0.22″ slot Mclaughlin Bennett Trevisi (MBT) prescription. Fav Anchor infrazygomatic crest (IZC) implants of 2 mm of head diameter and 14 mm length were inserted between first and second molar and 2 mm above the mucogingival junction in the alveolar mucosa and in the anterior region, two titanium mini-implants of 1.4 mm head diameter and 6 mm length. The screws were loaded immediately with e-chain with a minimal force from mini-implants in the anterior region to crimpable hook placed between lateral and canine and continuing the same till the IZ implants. To measure the amount of distalization and reduction of gummy smile, pre- and postlateral cephalograms were taken and assessed. Pre- and postdistalization and intrusion readings of all patients were obtained and calculated statistically for quantifying the amount of distalization of maxillary arch and intrusion for reduction of gummy smile. RESULTS: The distalization of the maxillary arch achieved was 4.6 mm which is clinically and statistically significant. The anterior teeth in the study were intruded with a minimum of 3.8 mm which is clinically and statistically significant; the gingival smile line was reduced with a mean of 3.4 mm which is clinically and statistically significant. Overbite correction of 4 mm was done with the mean difference of 4 mm which is also statistically significant. CONCLUSION: The IZ bone screws can be effectively used as an absolute anchorage to correct class II skeletal discrepancy with gummy smile devoid of premolar extraction with noninvasive procedure. CLINICAL SIGNIFICANCE: The use of IZC implants along with anterior implants, a biomechanical approach is effective in achieving full-arch distalization of maxilla and intrusion as the force vectors allow that the line of action passes through the center of resistance (Cr) of the entire maxillary arch, facilitates the distalization and intrusion of the maxillary arch, establishes ideal occlusion, and improves the smile esthetics.

[Comparative efficacy of Botox and surgical lip repositioning in the correction of gummy smile]. / Sravnitel'naya effektivnost' vvedeniya botoksa i khirurgicheskoi operatsii dlya korrektsii polozheniya gub pri desnevoi ulybke.

BACKGROUND: A smile plays an important role in determining a person's initial impression. OBJECTIVE: This study aims to evaluate the effectiveness of both injection botulinum toxin type A (botox) and surgical lip repositioning in the correction of the gummy smile due to hyperactive upper lip according to the resulting smile and the patients' satisfaction. MATERIAL AND METHODS: The study consisted of 24 patients: 12 received the BTX-A (botulinum toxin type-A) injection and the remaining 12 underwent the surgical procedure (lip repositioning). The patients rated their satisfaction according to their gingival display that was defined as the difference between the lower margin of the upper lip and the superior margin of the right incisor, and patients were followed at 2 weeks, 2 months, and 6 months. Post injection and post-surgery with changes documented by photographs. Both groups answered a questionnaire addressing the overall appearance and they were asked to rate the improvement of their smile according to a 5-point aesthetic scale. RESULTS: The patients rated the effects of BTX-A as highly favorable if we take into consideration that BTX-A had a temporary effect while the surgical procedure (lip repositioning) had a relapse likelihood of more than 80% because the lip reverted back to its original position with almost complete relapse after 6 months and not to mention the risks affiliated with the surgical procedures. CONCLUSION: BTX-A injection exhibits better results than those of surgery and had given safer and more satisfactory results and achieved the required cosmetic patient requirement than lip repositioning.

Botulinum Toxin Type-A for the Treatment of Excessive Gingival Display on Smiling.

AIM AND OBJECTIVE: To determine the effect of botulinum toxin type-A (BTX-A) in reducing gummy smile. MATERIALS AND METHODS: This was an interventional case series conducted at a tertiary care setting in Mangaluru, Karnataka, India. Twenty patients with the gingival display of >3 mm were selected through convenience sampling technique. 2.5 units of BTX-A were injected under sterile conditions on either side of the face. The effect of the injection on gingival display was measured at the interval of 2, 4, 12, and 24 weeks. At the end of the treatment, the patient was asked to smile and was photographed and was compared to pretreatment photo. Repeated measures analysis of variance (ANOVA) was used to detect the change at each interval and intergroup comparisons were performed using post hoc Bonferroni test. RESULTS: The mean gingival exposure reduction from 4.93 to 3.705 mm at week 2. At the end of 24 weeks, the evaluation showed the mean gingival display of 4.755 mm on administration of 2.5 units on either side. The photographs also showed the change in smile at the end of the treatment. CONCLUSION: From the study, it was inferred that botulinum toxin was effective in eliminating gummy smile along with noticeable decrease in the nasolabial fold despite for the effect lasting only about 24 weeks. CLINICAL SIGNIFICANCE: A nonsurgical method of correction of gummy smiles when compared to surgical intervention is readily accepted by patients. Botulinum toxin type-A for gummy smiles is an effective, conservative, and satisfactory technique.

A comparison between modified and conventional surgical techniques for surgical lip repositioning in the management of the gummy smile.

AIM: The aim of this study was to evaluate and compare conventional and modified lip repositioning surgical techniques used for management of gummy smile involving hyperactive lip elevator muscles. METHODS AND MATERIALS: A prospective study was conducted between April 2016 and May 2017. Twenty two adult patients aged 18-38 years with gummy smile ranging from 4 to 6 mm because of soft tissue disorders were included in the study. All patients were treated in the oral and maxillofacial department at Damascus University. The sample was divided into two groups of 11 patients. The first group was treated by the conventional standard technique, and the second group treated by a modified study technique. The amount of gingival display in full smile was evaluated in both groups following each intervention. RESULTS: Both groups exhibited a statistically significant reduction in the measurement of gummy smile at month 1 and 6 postoperatively (P < .05), but there was no significant difference in gingival display at 3 months in either group postoperatively (P > .05). The recent study showed a significant difference in gingival display between 3 and 6 months postoperatively in group 1, but no significant difference in group 2. CONCLUSION: This study showed that the modified technique utilized in treating gummy smile has less relapse after surgery, shows excellent cosmesis and compared to the conventional technique, greater sustainability. CLINICAL SIGNIFICANCE: The recent increase in demand for an esthetic smile has led to the development a modification of conventional lip repositioning for correcting gummy smile by myotomy of lip elevator muscles. This modified technique offers less relapse and greater stability post-operatively than the conventional technique.

Impact of excessive gingival display on oral health-related quality of life in a Southern Brazilian young population.

AIM: To compare oral health-related quality of life (OHRQoL) between individuals with and without excessive gingival display (EGD). MATERIALS AND METHODS: A cross-sectional study was conducted in 53 individuals with EGD and 53 controls matched for sex and age. The outcome was OHRQoL, determined using the Oral Health Impact Profile (OHIP-14) and self-perceptions of satisfaction with smile aesthetics. A clinical examination was conducted to evaluate the smile line, colour of the teeth, tooth wear and malocclusion. Poisson regression was used to model the association between excessive gingival display and OHRQoL. RESULTS: Participants with EGD had higher total OHIP-14 score (4.81 ± 4.76) in comparison with the controls (1.85 ± 3.77; p < .001). The percentage of satisfied with smile individuals without and with EGD was 78.9% and 21.1%, respectively (p = .005). In the multivariate analysis, total OHIP-14 scores were 2.10-fold higher individuals with EGD, independently of the other variables analysed. Impacts were evident on the functional limitation, psychological discomfort, psychological disability and social handicap. CONCLUSIONS: The occurrence of EGD exerted a negative impact on OHRQoL independently of confounding variables in this specific population. The present findings justify the planning of treatment for individuals with EGD that impacts quality of life.

New Insights into the Anatomy of the Midface Musculature and its Implications on the Nasolabial Fold.

BACKGROUND: The prominent nasolabial fold is a distinct feature of the aging midface. As minimally invasive procedures have become mainstream, chemodenervation is a preferred method for treating dynamic facial rhytids. We therefore sought to identify relevant nasolabial fold and midfacial muscular anatomy to determine the ideal location of neuromodulation to improve the aesthetics of the midface and nasolabial fold without altering the upper lip and smile. METHODS: Twelve hemifacial cadaveric dissections were performed to identify midface muscle origin, insertion, width, vector of pull, and neighboring structures. Attention was focused on the levator labii superioris alaeque nasi (LLSAN), levator labii superioris (LLS), nasalis, and orbicularis oculi. Measurements were obtained based on surface landmarks including the medial canthus for future neurotoxin injection. RESULTS: The LLSAN inserts into the medial nasolabial fold and alar base, while the LLS inserts into the middle third of the nasolabial fold. The broadest portion of the superior LLSAN was on average 8.4 mm inferior and 4.6 mm medial to the medial canthus. A separate muscle obliquely oriented between the orbicularis oculi and LLSAN was identified and found to insert into the malar fat pad. This "malar levator" was present in all specimens and has implications on medial periorbital rhytids and the tear trough deformity. CONCLUSION: This study further defines midfacial and nasolabial fold muscular anatomy and provides new insights into the use of neuromodulators for these areas without affecting upper lip position. The malar levator muscle appears to be a separate midfacial muscle with independent action. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Anatomic basis of Le Fort 1 impaction osteotomy: a radiological study.

PURPOSE: In Le Fort 1 osteotomy when a maxillary impaction is necessary, surgeons have to face different anatomical problems. (1) To determine the best bone resection route, they have to consider the situation of dental roots, infraorbital foramen and maxillary artery. (2) In case of Le Fort 1 osteotomy combined with a mandibular sagittal split osteotomy, the palate has to be replaced in horizontal position although there is no anatomical landmark. (3) In case of Gummy smiles, it can be due to either long face or short upper lip. The main objective was to identify safe bony landmarks to perform a Le Fort I osteotomy and to find a reliable way for repositioning the palate horizontally; the secondary objective was to determine the upper lip normal length. METHODS: The study was based on 178 facial CT examinations. The following parameters have been used: the vertical length of the upper lip, the vertical heights of the anterior nasal spine, the canine and molar roots, the inferior limit of the pterygomaxillary fossa and the vertical height of the infraorbital foramen on both sides. RESULTS: The vertical length from the subnasal point to the upper vermilion was 15.06 ± 3.09 mm, and to the junction of the upper and lower lips was 23.94 ± 3.79 mm. The vertical length from the anterior nasal spine to the incisor alveolar border was 19.70 ± 3.17 mm. The height of the canine root was 17.11 ± 2.60 mm. The height of the highest lateral root of first or second maxillary molars was 11.71 ± 1.83 mm. The vertical length from the inferior limit of the pterygomaxillary fossa (pti point) to the alveolar border of the pterygomaxillary suture was 19.86 ± 3.45 mm. The height from the center of the infraorbital foramen to the alveolar border of the maxilla on a vertical line was not statistically different on right and left sides. CONCLUSIONS: According to our results, in impaction Le Fort 1 osteotomy, the bone resection must pass 20 mm above the alveolar border in canine area, and 15 mm above the alveolar border in molar area. The resection has to end less than 20 mm above the inferior border of the pterygomaxillary suture. The vertical height of the infraorbital foramen is a consistent landmark for repositioning of the palate in a horizontal plane.

Botulinum Toxin for the Treatment of Gummv Smile.

AIM: The aim was to evaluate the effect of botulinum toxin (Botox) injections as a conservative treatment for gummy smile. MATERIALS AND METHODS: An experimental in vivo study was conducted at a dermatology clinic in Riyadh in January 2016. The study included 23 female patients who ranged from 20 to 50 years and were treated with Botox injections due to excessive maxillary gingival display. The patients with short clinical crowns or long maxilla, those who were pregnant or breastfeeding, and patients with neuromuscular disorders were excluded. Patients received Botox type I, injected 3 mm lateral to the alar-fascial groove at the level of the nostril opening at the insertion of the levator labii superioris alaeque nasi muscle. Photos were taken of the patient's smile before and after the treatment and were then uploaded to the SketchUp program to calculate improvements in gingival display. The distance from the lower margin of the upper lip to the gingival margin was calculated pre- and posttreatment. The amount of improvement was calculated as (pre-Botox treatment - post-Botox treatment/pre-Botox treatment × 100). The mean percentage of the total improvement was analyzed. RESULTS: A total of 23 female patients received treatment to improve their gummy smile. Improvement was clear 2 weeks after Botox injection. The mean percentage of improvement in the gingival display was 99.6%. CONCLUSION: Botox type I is an effective conservative technique to improve gummy smile caused by muscular hyperfunction. CLINICAL SIGNIFICANCE: Patients' retention highly indicated that they were satisfied with the provided treatment by Botox injections. Improving the quality of life with least painful experience and immediate results was the major advantage for Botox type I.