Hypermobile upper lip is highly prevalent among patients seeking treatment for gummy smile

Dose and injection site of botulinum toxin type A for gummy smile management: A systematic review and bibliometric analysis

INTRODUCTION

Botulinum toxin type A (BoNT/A) is an effective non-surgical method for treating gummy smile (GS). This systematic review evaluated the efficacy, duration, and safety of different BoNT/A injections.

METHODS

Four electronic databases were searched for relevant literature, generating 1106 references.

RESULTS

The review included 13 prospective, controlled clinical trials. The mean pre-injection anterior gingival exposure ranged from 3.5 mm to 6.8 mm, reaching maximum effect at 2-4 weeks post-injection. Most studies indicated complete improvement in gingival exposure post-injection, with gingival exposure reduced to ≤3 mm. The dosage of BoNT/A was determined by the severity of gingival exposure, with effects lasting up to 12-24 weeks. Levator labii superioris alaeque nasi (LLSAN), levator labii superioris (LLS), and zygomaticus minor (ZMi) were the main targeted muscles. Next, bibliometric analysis was conducted to provide an overview of the existing publications on managing gummy smiles.

CONCLUSIONS

This data demonstrates that BoNT/A can effectively treat various types of GS triggered by muscle hyperactivity. It is a non-intrusive treatment with significant improvement, high safety, minimal side effects, and high patient satisfaction. This study was preregistered in the Prospective Register of Systematic Reviews (CRD42024509183).

CLINICAL SIGNIFICANCE

This study systematically reviewed and compared previous results on efficacy, duration, patient satisfaction, and adverse effects of different botulinum toxin type A doses and injection sites, laying a solid foundation for further studies that use BoNT/A in the management of gummy smiles.

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.

Lip repositioning as a complement to gummy smile treatment - A case report

The aim of this case report was to present an alternative therapeutic combination involving lip repositioning (LR) in the correction of gummy smile (GS). This treatment is less invasive than orthognathic surgery and is highly acceptable to patients, using a modified technique that combines myotomy with the insertion of polyester threads as a physical barrier against relapse.

Maxillary exostoses as contributing etiology to lip hypermobility and associated excessive gingival display: A clinical report

Several etiologies may contribute to the development of excessive gingival display (EGD). However, little, if any, consideration has been given to the potentially significant role of prominent buccal maxillary exostoses (BMEs) in EGD etiology. Therefore, the aim of this report was to highlight the contribution of BMEs to EGD. Two patients complaining of EGD were evaluated, and BMEs were found associated with a hypermobile upper lip, vertical maxillary excess, and altered passive eruption. Both patients received esthetic crown lengthening (ECL) as the first surgical intervention. The BMEs were removed by osteoplasty performed during ECL. The resulting smile and EGD changes were evaluated 3 to 6 months postoperatively. An extraordinary amount of gingival display reduction was found in both patients (8 mm and 6 mm), a highly atypical outcome for ECL alone. BME removal on its own represented 75% and 67% of the EGD decrease, respectively. The exostoses removal-associated EGD decreases corresponded to observed reductions in lip mobility during smile. Sizeable BMEs can contribute significantly to the etiology of EGD, in part through an effect on lip mobility during smile. Proper management of such BMEs through osteoplasty provides meaningful EGD reduction, resulting in improvements of smile esthetics and patient satisfaction.

Etiologies of excessive gingival display in a Saudi population

Introduction

Excessive gingival display (EGD) is a mucogingival deformity characterized by overexposure of the maxillary gingiva while smiling. This cross-sectional study aimed to identify EGD etiologies and their prevalence in participants at King Saud University, Saudi Arabia.

Methods

Adults with a gummy smile, who resided in Saudi Arabia, were nonsmokers, had good overall health, and had all their maxillary anterior teeth were eligible for inclusion. Participants were first screened by phone, and those who met the eligibility criteria were further screened at the Dental University Hospital (King Saud University, Riyadh, Saudi Arabia). The demographic characteristics of all eligible participants were recorded. Participants were further subjected to extraoral examination, which included gingival display (GD), vertical maxillary excess (VME), hypermobile upper lip (HUL), smile line, altered passive eruption (APE), gingival overgrowth, and short upper lip (SUL). Intraoral examination included periodontal pocket depth and bleeding upon probing. Student's t-test was used to compare the mean GD values across the main etiologies (VME, HUL, APE, and SUL).

Results

All 123 participants (mean age: 23.1 ± 0.2 years; 74 females) had EGD (i.e., GD ≥ 4 mm), of whom 55 (44.7 %) had a single etiology, and the remaining 68 (55.3 %) had > 1 etiology. APE was the predominant etiology (n = 90, 73.2 %) in the study population. Of these (n = 90), APE alone was prevalent in 29 (32.2 %) participants, whereas the remaining patients had APE in combination with other EGD etiologies (n = 61; 67.8 %). The presence of more than one EGD etiology in the same participant was associated with greater GD. The VME and HUL were significantly associated with smile line classes (p < 0.05).

Conclusions

APE (alone or in combination) was the predominant etiology of EGD in the study population. The presence of multiple EGD etiologies in the same patient emphasizes the need for an etiology-based, sequential, and multiple-treatment strategy to effectively manage EGD.

Facial, dental, periodontal, and tomographic characteristics of the etiology of excessive gingival display: a cross-sectional clinical study

PURPOSE

In this study, we examined the facial, dental, periodontal, and tomographic features associated with excessive gingival display (EGD) when smiling in young adults self-reporting a "gummy smile," categorized by potential etiology.

METHODS

The study included 25 healthy adults (18-42 years old; 23 women and 2 men) who self-reported EGD. Participants completed a health questionnaire and underwent a periodontal examination assessing probing depth, clinical attachment level, keratinized gingival width, and gingival thickness (GT). Extraoral and intraoral photographs were taken for smile analysis and to determine facial and dental characteristics. Cone-beam computed tomography (CBCT), performed with a lip retractor in place, was used to measure the distance from the gingival margin (GM) to the cementoenamel junction (CEJ), the distance from the CEJ to the alveolar crest, buccal bone thickness, and GT. The extent of EGD when smiling was quantified as the distance from the GM at the upper central incisor to the upper lip edge when smiling fully. The smile was categorized into 4 types based on gingival exposure characteristics observed during full smile.

RESULTS

Most participants were female (92%), with a mean age of 28.77±6.56 years. The average EGD was 4.2±2.44 mm, extending bilaterally from the anterior to the posterior maxilla. Two primary etiological factors were identified, alone or in combination: vertical maxillary excess (VME), predominantly indicated by an anterior maxillary height greater than 29 mm and a large interlabial gap; and altered passive/active eruption (APE), primarily characterized by square teeth (64%), upper central incisor width-to-height ratio (CIW:CIH) exceeding 87.5%, and GM-CEJ distance on CBCT exceeding 2 mm.

CONCLUSIONS

These findings suggest a multifactorial etiology of EGD, primarily associated with VME and APE. Clinical periodontal examination, CBCT conducted with a lip retractor, CIW:CIH, and soft tissue facial cephalometric analysis may aid in identifying the etiological factors of EGD.

A Smile Reimagined: Gummy Smile Resolution with Cutting Edge Method Using Chu's Gauge and Polymethylmethacrylate (PMMA) Bone Cement

Excessive gingival display (EGD) is one of the most common aesthetic concerns, and its correction often presents a challenge to periodontists. It has a multifactorial etiology, and this article describes a case involving hypermobile upper lip (HUL), altered passive eruption (APE), and vertical maxillary excess (VME). Upon investigation, a positive collum angle and marked subnasal skeletal depression were observed. In this context, it is noted that during a spontaneous smile, the upper lip retracts and gets lodged in this depression. The rehabilitation plan includes included aesthetic crown lengthening via gingivectomy using Chu's proportional gauge for altered passive eruption and filling the subnasal depression by PMMA (polymethylmethacrylate) bone cement. The entire treatment plan was digitalised using cutting edge methods such as computed tomography (CT), cone beam computed tomography (CBCT), and 3D printers for virtual planning of the defect's position, size, and shape. No postoperative complications were reported. After six months, the patient exhibited a harmonious smile with reduced exposed gingiva.

Esthetic Crown Lengthening and Minimally Invasive Laminate Veneers to Resolve Altered Passive Eruption

Background

Altered passive eruption (APE) in the esthetic zone can be an esthetic concern to the patient. To restore adequate crown dimensions, crown lengthening procedures may be necessary.

Methods

The present case is a report of a patient with an unsatisfied smile due to a complaint of short clinical crowns. The periodontal diagnosis was APE and deviated maxillary anterior midline. A mock-up was made to assist the provider in evaluating the patient's esthetic concerns and acceptance of the proposed treatment plan.

Results

Esthetic crown lengthening and ultrathin ceramic laminate veneers were used to treat an APE type I subdivision B, resulting in a gingival display reduction and in final PES/WES scores of 10.

Conclusion

The use of periodontal plastic surgery in conjunction with ultrathin ceramic laminate veneers was mandatory to restore an unesthetic smile. The proposed treatment reduced the gingival display significantly and increased the crown height to length proportions reaching an esthetic smile and patient satisfaction.

Effects of polymethyl methacrylate-based bone cement graft for treating excessive gingival display and its dimensional facial changes: 12-Month clinical study

Objective

to present a 12-month follow-up with photographic and tomographic analyses of the effect of polymethyl methacrylate-based bone cement graft (PMMA) in gingival exposure (GE) in patients with excessive gingival display (EGD).

Methods

Twelve patients with EGD were included. The PMMA was surgically placed. A frontal and lateral photograph protocol was performed at baseline (T0), 3 (T3), 6 (T6), and 12 months (T12) post-operatively. Soft tissue cone-beam computed tomography (ST-CBCT) was performed at T0 and T12. Measures included GE, length of the lip vermilion (LLV), lip shape (LS), nose width (NW), filter width (FW), nasolabial angle (NAS) while smiling, and nasolabial angle at rest (NAR). The height, thickness, and volume of the cement graft were also measured in the ST-CBCT. The comparisons were performed by Kruskal-Wallis test at 5 % of significance (p < 0.05).

Results

The height, thickness, and volume of the PMMA were respectively 12.84 ± 1.59 mm, 3.83 ± 0.53, and 1532.02 ± 532.52 mm3. PMMA significantly decreased GE from 8.33 ± 1.25 mm (T0) to 6.60 ± 0.93 mm (T12) (p < 0.01). NAR was 98.34 ± 9.28° at T0 and increased to 105.13 ± 7.33° at T12; however, the angle value was not statistically different (p = 0.08). LLV, LS, NW, FW, and NAS did not exhibit statistical differences between the baseline and follow-up periods.

Conclusions

PMMA significantly decreased GE in a 12-month follow-up without influencing adjacent soft tissue anatomical structures.

Upper lip characteristics and associated excessive gingival display etiologies in adults: Race and sex differences

BACKGROUND

This cross-sectional study aimed to examine upper lip (UL) and smile characteristics and soft tissue excessive gingival display (EGD) etiologies (hypermobile upper lip [HUL], altered passive eruption [APE], and short upper lip [SUL]) in a nondental adult population and to analyze interracial (Black and White) and intersex differences.

METHODS

Community participants, non-Hispanic Blacks (NHB) and non-Hispanic Whites (NHW), were recruited and examined for UL vertical dimensions at rest and maximum smile and for HUL, APE, and SUL. Associations between gingival display (GD) or EGD and UL anatomical characteristics, HUL, APE, and SUL were analyzed.

RESULTS

Participants included 66 NHB and 65 NHW adults. Ergotrid height (greater among NHW; p = 0.019) averaged 14.0 mm. Upper lip vermilion length (ULVL), total UL length, internal lip length, total UL length during smile, and UL mobility averaged 8.6, 22.5, 23.1, 16.6, and 5.9 mm, respectively (all significantly greater in NHB; p ≤ 0.012). SUL prevalence was 4.6%, found only among NHW. Lip length change from rest to smile (LLC) averaged 26.2% (significantly greater in females; p = 0.003). HUL prevalence was 10.7% (NHB 13.1%, NHW 3.5%; p = 0.024). NHB had significantly greater GD (p ≤ 0.017). EGD and APE prevalence (6.9% for both) showed significant interracial and intersex differences (p ≤ 0.014). Multivariate logistic regression analyses indicated that LLC and HUL were the most consistently significant EGD determinants.

CONCLUSIONS

UL anatomical and functional characteristics and soft tissue-related EGD etiologies exhibit significant interracial and intersex differences, with UL mobility/hypermobility being the most consistently significant determinant of GD.

Clinical and psychological impact of lip repositioning surgery in the management of excessive gingival display

Background

Excessive gingival display (EGD), also known as a gummy smile, is characterized by overexposure of the maxillary gingiva on smiling. EGD can cause embarrassment and reduce patient satisfaction. This study aimed to evaluate the clinical and psychological effects of lip repositioning surgery on the management of EGD.

Methodology

This experimental study enrolled 14 patients with EGD who had undergone a modified lip repositioning technique, which comprised moving two strips of mucosa bilaterally to the maxillary labial frenum and repositioning the new mucosal margin coronally. The extent of gingival display (GD), lip mobility (LM), total lip length (TLL), lip length (LL), and internal lip length (ILL) was measured at baseline and 6 months postoperatively. The pre-operative psychological assessment was conducted using the social appearance anxiety scale (SAAS) scores, whereas the postoperative assessment was conducted using SAAS and visual analog scale (VAS) scores at 1 week, 3 months, and 6 months postoperatively.

Results

Among the clinical parameters, TLL increased by 2.0 ± 1.038, LL increased by 2.28 ± 0.99, ILL reduced by 2.78 ± 1.36, LM reduced by 3.21 ± 1.12, and GD reduced by 3.14 ± 0.77 at 6 months postoperatively. Among the psychological parameters, SAAS reduced by 31.42 ± 1.907 from the baseline to 6 months, whereas the VAS score reduced to 3.14 ± 0.27 at 6 months postoperatively.

Conclusion

A significant reduction in GD, which is largely dependent on strict case selection, pain, and social anxiety was observed in this study, indicating that lip repositioning surgery is effective in managing EGD.

Evaluating smile aesthetic satisfaction and related smile characteristics in dental students

Aim

This study aimed to assess the association between self-rated smile satisfaction and the smile dimensions among dental students.

Method

An analytical cross-sectional study was conducted on 216 Vietnamese dental students. A standardized photograph was taken of each student with their frontal social smiles to assess aesthetic dimensions. A single-session self-administered questionnaire containing five questions about smile aesthetic satisfaction related to various aspects was administered to all students. Differences in smile characteristics and satisfaction scores between the two genders were evaluated. The impact of smile characteristics on satisfaction scores was assessed using multiple linear regression models.

Results

Most dental students had a high smile line, parallel smile arcs, an upward upper lip curvature, a non-touching labiodental relationship, a dental midline that coincided with the midline of the face, and eight teeth displayed during smile. Most participants were satisfied with their smiles, and the self-rated satisfaction score was 67 out of 100. Self-perceived overall smile satisfaction was associated with the "smile arc", the "upper lip curvature", the "number of teeth displayed during smile", and the "dental midline". Female students had a statistically significant correlation between self-perception and smile characteristics, such as upper lip curvature, dental midline shift, and smile line.

Conclusions

The smile arc, upper lip curvature, and dental midline shift affected self-perceived satisfaction among dental students. Female students showed an association between the smile parameters and self-perceived satisfaction.

Gummy Smile Prevalence Among Ha'il City Female Young Adults and Its Impact on Quality of Life: A Cross-Sectional Study

BACKGROUND

Gummy smile (GS) has a direct effect on individuals, especially among young adults, because of its association with smile avoidance. The younger populations are sensitive about their smiles and prefer aesthetic, beautiful smiles, a lack of which can negatively impact their quality of life.

OBJECTIVES

This study aims to measure the GS prevalence among young adults aged 16 to 18 attending high schools in Ha'il City, Saudi Arabia, evaluating oral health related to quality of life (OHQoL) in those suffering GS by using the OHQoL questionnaire (OHIP-14).

METHODS

A cross-sectional study was conducted on 385 female high school students located in Ha'il. Students with GS took a survey on oral health using OHIP-14. For this, SPSS was used to analyze the data.

RESULTS

The study included 200 people with GS (52%). The mean age was 18±0.01. The prevalence of GS was analyzed, with a mean value of 4.68±1.2 mm, indicating most students had GS ranging between 4 and 5 mm. The most frequent value for all items in the OHIP-14 questionnaire was 1, indicating that students often had their quality of life affected. The non-parametric Kruskal-Wallis test indicated the results had a significant value (p < 0.05), showing a positive and significant association.

CONCLUSION

Based on the OHIP-14 questionnaire and respecting the methodology, it was concluded that the quality of life has been affected for all female students with GS. The high prevalence for ages 16-18 showed most students agreed their lives were being affected by GS and their condition needed to be treated. It was also confirmed by the significant association of GS with items of oral health and quality of life.

Contemporary treatment techniques for excessive gingival display caused by altered passive eruption or lip hypermobility

OBJECTIVES

Excessive gingival display (EGD), also known as gummy smile, has various causes, including altered passive eruption (APE) and hypermobile upper lip (HUL). This state-of-the art narrative review explores current concepts regarding soft tissue EGD etiologies and the contemporary modalities available for APE or HUL treatment.

DATA, SOURCES, STUDY SELECTION

Literature search was conducted for a narrative review on the etiology, diagnosis, and treatment of EGD caused by APE and HUL. Searching for articles was carried out in PubMed and Google Scholar. Published articles, including case reports, case series, observational and interventional clinical trials, and critical appraisals of the literature (e.g., systematic reviews) on the etiology, diagnosis, and treatment of EGD caused by APE and HUL were retrieved and reviewed. Particular focus was placed on novel treatment modalities introduced in the last five years.

CONCLUSIONS

Recent research evidence indicates that APE and HUL are the two major soft tissue-based EGD etiologies. Aesthetic crown lengthening (ACL) and lip repositioning surgery (LRS) are the established surgical treatment modalities for APE and HUL, respectively. The last few years have seen the introduction of new techniques for APE and HUL management, an expansion of the available ACL and LRS technique variations, and additional evidence further supporting the effectiveness of these two procedures. Several of the recently introduced approaches offer unique, innovative, and potentially impactful concepts. However, for many of these newly described treatments the available evidence is limited to case reports and the exact indications remain to be adequately defined.

CLINICAL SIGNIFICANCE

Altered passive eruption and hypermobile upper lip are the common soft tissue causes of gummy smile and can be successfully managed through aesthetic crown lengthening and lip repositioning surgery, respectively. A wide range of newly introduced approaches promises to further facilitate gummy smile treatment and improve outcomes.

Digital Smile Makeover: A Multidisciplinary Team Approach

Aesthetics is a fundamental part of contemporary dental practice. A pleasant smile depends on the gingival tissue architecture and dental characteristics. Excessive gingival display (gummy smile) is considered an unattractive smile and can affect a person's confidence. There are many etiological factors related to a gummy smile. Aesthetic rehabilitation of these cases often requires an interdisciplinary approach and close collaboration between dental specialties. This article describes an approach to excessive gingival display management caused by short teeth and hyperactive lips using a digital workflow for crown lengthening. A digital approach enables predictable planning and decreases the need for postsurgical modifications, thus shortening the treatment duration. Computer software is used for planning and 3D-printed guide for crown lengthening and implant placement. Two months later, lip repositioning was performed to reduce the hyperactive lip. After 4 months, prosthetic treatment and Botox injections were done to restore an aesthetic smile.

Treatment of gummy smile combining crown lengthening, lip repositioning, and the use of polyester threads

INTRODUCTION

The case report presents a new possibility of treatment for a gummy smile in a patient with multiple etiologies, such as altered passive eruption and hypermobility upper lip. At first, crown lengthening was not sufficient to achieve the desired aesthetic result, being necessary its combination with lip repositioning.

CASE PRESENTATION

Crown lengthening surgery (CLS) was performed in a 20-year-old woman, with a gingival display of 7.5 mm, having her gingival exposure reduced to 5.5 mm. Because the patient continued unsatisfied after 6 months, a new procedure was adopted. To reduce even more her gingival exposure, lip repositioning technique was performed associated with myotomy and the insertion of polyester threads as a physical barrier to prevent relapse.

CONCLUSION

The result of the gingival display was reduced to 2.5 mm, removing the condition of a gummy smile after the combination of both techniques: crown lengthening, and lip repositioning.

KEY POINTS

Why is this case new information? Association of the technique of lip repositioning and myotomy, the insertion of polyester threads that act as a physical barrier against recurrence. What are the keys to successful management of this case? Correct etiological diagnosis. Prior application of botulinum toxin. Respect the period of 1 month for the insertion of the polyester thread, helping to preserve the suture (limitation of movement). What are the primary limitations to success in this case? Make the patient aware not to move the lips with the hands in order to observe the incision.

A Modified Approach in Lip Repositioning Surgery for Excessive Gingival Display to Minimize Post-Surgical Relapse: A Randomized Controlled Clinical Trial

Lip repositioning surgeries are performed to treat patients with excessive GD (EGD). This study aimed to explore and compare the long-term clinical results and stability following the modified lip repositioning surgical technique (MLRS) with the addition of periosteal sutures compared to the conventional lip repositioning surgery (LipStaT^®) in order to address EGD. A controlled clinical trial with female participants (n = 200) intended to improve their gummy smile were divided into control (n = 100) and test (n = 100) groups. The gingival display (GD), maxillary lip length at rest (MLLR), and maxillary lip length at maximum smile (MLLS) were measured at four time intervals (Baseline; 1 Month; 6 Months, and 1 Year) in millimeters (mm). Data were analyzed by t-tests, Bonferroni-test, and regression analysis using SPSS software. At the one-year follow-up, GD for the control and test groups were 3.77 + 1.76 mm and 2.48 + 0.86 mm, respectively, and their comparisons showed that GD was considerably lower (p = 0.000) in the test group compared to the control group. The MLLS measurements taken at baseline, one-month, six-month, and one-year follow-up showed no significant differences (p > 0.05) between the control and test groups. At baseline, one-month, and six-month follow-up, the mean and standard deviation for the MLLR were almost similar, with no statistically significant difference (p = 0.675). The MLRS is a successful and viable treatment option for the treatment of patients with EGD. The current study showed stable results and no recurrence with MLRS until the one-year follow-up compared to LipStaT^®. With the MLRS, a 2 to 3 mm decline in EGD is usually to be expected.

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.

A Lip Repositioning Technique Using Polyester Threads for Gummy Smile Treatment

A new technique is proposed in this study to correct the gummy smile (GS) with myotomy, combining lip repositioning with the insertion of polyester threads at the surgical site to act as a physical barrier and control relapse. 11 patients were clinically assessed (30.2 ± 7.43 years old, 90.9% females and 9.10% males). All patients presented gingival display (GD) greater than 4 mm. Hypermobile upper lip (HUL), vertical maxillary excess (VME) + HUL, altered passive eruption (APE) + HUL, and VME + APE were the etiologies identified. Three polyester threads were inserted in each patient one month after the surgery. The GS was measured before, 6 months, and 12 months after the surgery. The results showed a reduction in the mean GD of the patients, 4.42 mm after 6 months (p value = 0.000) and 4.13 mm after 12 months (p value = 0.000). The largest relapse was 0.29 mm and was not statistically significant (p value = 0.07). The Friedman test with pairwise comparisons was used to determine the existence of statistically significant differences in GD between the periods analyzed. The results showed that the proposed technique was successful in treating GS, presenting significant reductions in the GD 12 months after surgery and controlling the relapse.

Lip Repositioning Techniques and Modifications

A common etiology of excessive gingival display is hypermobile upper lip, which can be managed by non-surgical and surgical approaches. Among the surgical options, lip repositioning surgery is a relatively simple procedure with minimal complications. Since the original description of the technique almost 50 years ago, several minor and major modifications have been introduced. The available evidence indicates that, when applied to properly diagnosed cases, the technique is effective in reducing gingival display and results in improved smile esthetics and high patient satisfaction. This article reviews the various techniques and modifications and summarizes the reported outcomes of the procedure.

Laser-Assisted Lip Repositioning Surgery: A Modification to The Conventional Technique

Introduction: The lip repositioning surgical technique arose with the objective of correcting and harmonizing the act of smiling. Since the conventional technique was published, some modifications of the technique have been proposed in order to counteract postoperative recurrence and to achieve the best esthetic appearance of the smile. The objective of this paper was to describe the laser-assisted lip repositioning technique (laser-assisted LRS) with a 940nm diode laser and 2780nm Er,Cr: YSGG, as a modification to the conventional lip repositioning technique, for the treatment of a gummy smile. Case Report: The proposed technique consists in achieving the descent of the upper lip by removing the intraoral mucosal band through the laser peeling of oral mucosa, preserving the connective tissue intact for healing by secondary intention. The technique was implemented in two patients with a diagnosis of a gummy smile caused by a short and hyperactive upper lip; the healing process was satisfactory, and there was no bleeding or postoperative edema. Postoperative controls were performed at 3 and 10 months, and no recurrence was found. Conclusion: the 940nm Diode laser or 2780nm Er,Cr: YSGG laser-assisted lip repositioning technique described here is less invasive than that performed with a conventional scalpel, offers aesthetic results, lower risk of infection and recurrence of the gummy smile in the long term.

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.

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.

Aesthetic crown lengthening and lip repositioning surgery: Pre- and post-operative assessment of smile attractiveness

AIM

To assess the effect of aesthetic crown lengthening (ACL) and lip repositioning surgery (LRS) on perception of smile attractiveness.

MATERIALS AND METHODS

Preoperative and 6-month postoperative smile photographs of ACL- or LRS-treated patients were evaluated by 100 raters (five gender-balanced groups of ten per procedure) of diverse background (dental students, general dentists, periodontists and laypersons with and without any aesthetic concerns about their own smile). Smile attractiveness was rated by visual analogue scale (VAS). Multivariate mixed-effect models were applied to determine the effect of procedure, rater (age, gender and group) and case (gingival display and GD) on smile attractiveness rating.

RESULTS

Average preoperative and postoperative VAS scores for ACL patients were 3.8 ± 2.0 and 6.2 ± 1.9, respectively. Corresponding LRS patient values were 4.8 ± 2.0 and 6.4 ± 1.9. Treatment, baseline GD and rater age were significant determinants (p < .001) of smile attractiveness for both procedures. Rater gender was not significant. Rater group was significant (p < .032) only for ACL. Procedure (p < .001), baseline VAS (p < .001), change in GD (p ≤ .002) and rater age (p ≤ .017) were significant determinants of smile attractiveness change from preoperative to postoperative.

CONCLUSIONS

ACL and LRS are two periodontal plastic surgery procedures that deliver significant smile attractiveness improvements, in the eyes of both laypersons and dental professionals.

Lip repositioning surgery for gummy smile: 6-month clinical and radiographic lip dimensional changes

OBJECTIVES

The present case series aimed to examine lip repositioning surgery (LRS) outcomes related to changes in external and internal upper lip (UL) dimensions, utilizing both conventional clinical and novel radiographic approaches.

MATERIALS AND METHODS

Patients (n = 13) diagnosed with hypermobile UL (>8-mm mobility during smile) and excessive gingival display (≥4-mm) were included and assessed at baseline and 6 months postoperatively. Clinical parameters at rest included total lip and internal lip length (vestibular depth). At maximum smile included total lip, philtrum (ergotrid), and vermilion lengths. Cephalometric parameters included anterior maxillary height; lip length; nasolabial angle; anteroposterior lip thickness; internal lip length (vestibular depth); and vestibular fornix position (using novel approach employing radiopaque marker). Linear mixed-effect models, Pearson's correlation, and linear regression were used for statistical analyses.

RESULTS

LRS did not affect total UL length at rest (p = 0.418). It resulted in significant internal UL length decrease (-3.8 ± 2.1 mm, p < 0.001) and significant increases of vermilion length (1.9 ± 1.0 mm, p < 0.001) and anteroposterior lip thickness (0.7 ± 0.7 mm, p = 0.002). The clinical and radiographic measurements of total UL length at rest (r ≥ 0.734) and of internal UL length (r ≥ 0.737), and the two radiographic assessments of vestibular depth (r = 0.842), were strongly correlated.

CONCLUSIONS

LRS resulted in significant decrease of vestibular depth/internal UL length and in significant increases of UL vertical vermilion length and UL anteroposterior thickness, without affecting total UL length at rest.

CLINICAL RELEVANCE

The documented lip dimensional outcomes should help practitioners when treatment-planning LRS and counseling patients seeking treatment for hypermobile UL.

Smile dimensions affect self-perceived smile attractiveness

Facial expressions play a leading role in human interactions because they provide signaling information of emotion and create social perceptions of an individuals’ physical and personality traits. Smiling increases socially perceived attractiveness and is considered a signal of trustworthiness and intelligence. Despite the ample information regarding the social importance of an attractive smile, little is known about the association between smile characteristics and self-assessed smile attractiveness. Here we investigate the effect of smile dimensions on ratings of self-perceived smile attractiveness, in a group of 613 young adults using 3D facial imaging. We show a significant effect of proportional smile width (ratio of smile width to facial width) on self-perceived smile attractiveness. In fact, for every 10% increase in proportional smile width, self-perceived attractiveness ratings increased by 10.26%. In the present sample, this association was primarily evident in females. Our results indicate that objective characteristics of the smile influence self-perception of smile attractiveness. The increased strength of the effect in females provides support to the notion that females are overall more aware of their smile and the impact it has on their public image.

Experimental gingivitis in patients with and without altered passive eruption

BACKGROUND

Individuals with altered passive eruption (APE) are assumed to be more susceptible to periodontal diseases. To date, this hypothesis has not been sufficiently supported by scientific evidence. The aim of this study, using an experimental gingivitis model, was to examine the development and resolution of gingival inflammation in patients with APE when compared to patients with normal gingival anatomy.

METHODS

A localized experimental gingivitis was induced in 9 patients with APE (test group) and 9 patients without APE (control group) in the maxillary right quadrant. After 21 days, patients were instructed to resume proper home oral hygiene procedures. At baseline (day 0) and at days 7, 14, 21, 28, 35, and 42, plaque index (PlI), gingival index (GI), and gingival crevicular fluid volume (GCF) were evaluated for teeth 6 (canine), 7 (lateral incisor) and 8 (central incisor) of test and control groups.

RESULTS

During the experimental gingivitis phase (days 0 to 21), the rate of change in gingival inflammation (GI) was dramatically different between the APE test group and the control group. On day 21, at the time of maximum plaque accumulation, the GI of the APE test group was a 109% greater than the GI of the test group (P ≤ 0.001) despite similar plaque levels (P = 0.436). During the resolution of inflammation phase (days 22 to 42), the APE test group continued to exhibit statistically higher GI scores than the control group (P = 0.029).

CONCLUSION

In the presence of similar amounts of plaque deposits and plaque accumulation rates, APE patients exhibited differences in the development and resolution of plaque-induced gingival inflammation when compared to controls.