A comparative study of the use of digital technology in the anterior smile experience.

OBJECTIVES: this study aims to compare the clinical outcomes of traditional and digital crown extension guides in the aesthetic restoration of anterior teeth. Additionally, the study will analyze the differences in the results of various digital crown extension guides in anterior aesthetic restorations. METHODS: Sixty-two patients who required aesthetic restoration of their anterior teeth were selected for this study. The patients had a total of 230 anterior teeth and were randomly divided into three groups: a control group of 22 cases who received diagnostic wax-up with pressure film, an experimental group 1 of 20 cases who received 3D printed digital models with pressure film, and an experimental group 2 of 20 patients who received digital dual-positioning guides. The control group had a total of 84 anterior teeth, experimental group 1 had 72 anterior teeth, and experimental group 2 had 74 anterior teeth. The study compared three methods for fabricating crown extension guides: the control group used the diagnostic wax-up plus compression film method, while experimental group 1 used compression film on 3D printed models and experimental group 2 used 3D printed digital dual-positioning crown extension guides. After the crown lengthening surgery, the control group patients wore DMG resin temporary crown material for gingival contouring, while the experimental group patients wore 3D printed resin temporary crowns for the same purpose. The patients were followed up in the outpatient clinic after wearing temporary crowns for 1 month, 3 months, and 6 months, respectively. The clinical results were evaluated in terms of marginal fit, red aesthetic index, and white aesthetic index. RESULTS: Based on the statistical analysis, the experimental group required significantly fewer follow-up visits and less time for guide design and fabrication compared to the control group. Additionally, the surgical time for the experimental group was significantly shorter than that of the control group. During the postoperative period between the 1st and 3rd month, the PES index scores for the marginal gingival level, proximal, and distal mesiodistal gingival papillae of the experimental group showed a trend of superiority over those of the control group. By the 6th month, the marginal gingival level exhibited a significant difference between the experimental and control groups. The experimental group demonstrated superior results to the control group in terms of shape, contour, and volume of the teeth, color, surface texture, and transparency of the restorations, and features during the 1st and 3rd postoperative months. In the 6th month, the comparative results indicated that the experimental group continued to exhibit superior outcomes to the control group in terms of the shape, color, surface texture, and transparency of the restorations, as well as the characteristics of the teeth. Additionally, the experimental group demonstrated significantly fewer gingival alterations than the control group at 1 month, 3 months, and 6 months post-procedure, with this difference being statistically significant. Furthermore, the combination of 3D printing technology and restorative techniques was utilized, resulting in consistent patient satisfaction. CONCLUSION: Digitalisation plays an important role in anterior aesthetic restorations. The use of digital technology to manage the entire process of anterior cosmetic restorations can improve restorative results, reduce the number of follow-up appointments, shorten consultation time, and achieve better patient satisfaction.

Reanatomização estética dos dentes anteriores com resina composta: relato de caso / Reanatomización estética de dientes anteriores com resina compuesta: reporte de caso / Aesthetic reanatomization of front teeths with composite resin: case report

Introdução: A alta busca por tratamentos estéticos levou a indústria odontológica a aprimorar suas técnicas e desenvolver materiais com novas características que possibilitam a mimetização da estrutura dental, associando alta qualidade estética à saúde. Para isso, é necessário uma anamnese detalhada e exame físico intra e extrabucal, análise morfológica dos dentes e da face, para que a reabilitação proposta seja adequada. Objetivo: O objetivo deste estudo é descrever um caso clínico de reanatomização dos elementos dentais anteriores superiores, por meio de restaurações diretas em resina composta, restabelecendo a estética e função da paciente. Relato de caso: Paciente do sexo feminino, 19 anos, procurou a Clínica Escola da Faculdade de Odontologia do Recife -FOR relatando insatisfação com seu sorriso e declarou não estar disposta a se submeter a um tratamento ortodôntico. Ao realizar o exame clínico, observou-se que havia desalinhamento dos elementos dentários ântero-superiores. Após a realização do enceramento diagnóstico e validação da mesma através do mockupcom resina bisacrílica, optou-se por realizar a reanatomização estética com resina composta nanohíbrida, de forma conservadora, ou seja, sem desgastar os dentes em questão. Conclusão: As etapas do planejamento foram fundamentais para maior previsibilidade e obtenção do excelente resultado. Os materiais e técnicas selecionados para realização dos procedimentos aliaram características de resistência e estética, visando maior longevidade (AU).

Introduction: The high demand for aesthetic treatments has led the dental industry to improve its techniques and develop materials with new characteristics that allow mimicking the tooth structure, associating high aesthetic quality with health. This requires a detailed anamnesis,intra-and extraoral physical examination, and morphological analysis of the teeth and faceto allow an adequate proposed rehabilitation. Objective:The objective of this study is to describe a clinical case of reshaping of upper anterior teeth, by direct composite resin restorations, reestablishing the patient's aesthetics and function. Case report:Female patient, 19 years old, sought the Clínica Escola da Faculdade de Odontologia do Recife -FOR, reporting dissatisfaction with her smile and declared that she was unwilling to undergo orthodontic treatment. Clinical examinationrevealed misalignment of the upper anteriorteeth. After diagnostic waxing and validation by mockup with bis-acryl resin, it was decided to perform the aesthetic reshaping with nanohybrid composite resin in a conservative manner, i.e., without tooth wearing . Conclusion:The planning stages were fundamental for greater predictability and obtaining excellent results. The materials and techniques selected for the procedurescombined resistance and aesthetic characteristics, aiming at greater longevity (AU).

Introducción:La gran demanda para tratamientos estéticos ha llevado a la industria dental a mejorarsus técnicas y desarrollar materiales con nuevas características que permitan mimetizar la estructura dental, combinando una alta calidad estética con la salud. Para que esto ocurra, es necesario realizer una anamnesis detallada y un examen físicointra y extraoral, así como un análisis morfológico de los dientes y de la cara, para que la rehabilitación propuesta sea da adecuada. Objetivo:El objetivo de este studio es describir un caso clínico de reanatomización de los elementos dentales de resinacompuesta, restabeleciendo la estética y función de la paciente. Informe de caso:Paciente del sexo feminine, 19 años de edad, que acudió a la Clínica Escuela de La Facultad de Odontología de Recife ­FOR menifestando insatisfaccíon con su sonrisa y declarando no estar dispuesta a someterse a tratamiento de ortodoncia. En el examen clínico se observódesalineación de los elementos dentarios anterosuperiores. Tras realizar un encerado diagnóstico y validarlo con un mock-up de resina bisacrílica, se optó porrealizer una reanatomización estética con resina compuesta nanohíbrida de forma conservadora, es decir, sin desgastarlos dientes implicados. Conclusión:Las etapas de planificacíon han sido fundamentales para una mayor previsibilidad y la obtención de excelentes resultados. Los materiales y técnicas seleccionados para la realización de los procedimentos combinaron características de resistencia y estética, buscando una mayor longevidad (AU).

The surgical outcomes of anterior segmental osteotomy in Asian skeletal class II patients.

PURPOSE: Anterior segmental osteotomy (ASO) following the surgery-first approach is a long-established treatment modality to resolve lip protrusion in patients with skeletal class II patterns. However, the indications and effectiveness of ASO still remain uncertain. The objective of this study is to investigate the effectiveness of ASO in Asian skeletal class II patients by evaluating the skeletal and soft tissue changes and analyzing pre-treatment variables that determine successful outcomes in occlusal as well as esthetic aspects. METHODS: The lateral cephalograms of 44 skeletal class II patients who underwent ASO and orthodontic treatment for resolving lip protrusion were retrospectively collected. Hard and soft tissue variables of two groups, normalized (NG) and unnormalized (UNG) ANB after treatment were compared and analyzed. The rotational effect of the anterior segment on the hard and soft tissue was also investigated. RESULTS: ASO was successful in correcting the skeletal class II relationship and lip protrusion (ΔANB - 2.3°, 4-5 mm lips retraction) in most cases. However, for patients with severely camouflaged skeletal class II incisors involving a large ANB and SNA, a large ANB still remained post-treatment. The study also found that rotation of the upper and lower anterior segments further augmented the amount of lip retraction. CONCLUSIONS: ASO was found to successfully correct ANB of skeletal class II patients under the following conditions (ANB 5.3° ± 1.5°, SNB 77.3° ± 4.5°, U1 to FH 115° ± 7.5, L1 to FH 48.0° ± 4.6). However, patients with larger ANB and SNA values may require bi-maxillary surgery. In addition, ASO has limitations in correcting gummy smile in cases of extreme maxillary excess. For patients requiring a large amount of lip retraction, rotation of the anterior segment may be beneficial in conjunction with bi-maxillary surgery.

Neuromodulator Injection for Gummy Smile.

SUMMARY: Neuromodulators have become a treatment of choice for the management of excess gingival show, or "gummy smile." There have been many proposed algorithms for the optimal placement and dosage of neuromodulator to inject in these locations. The authors aim to clarify these points and provide surgeons with a reliable way to manage the gummy smile that results from hyperactive muscles of the midface.

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

BACKGROUND: Demand for less-invasive procedures for treating gummy smile, such as botulinum toxin A injections, has increased substantially over the years. Meanwhile, the optimal injection site for botulinum toxin A injection is debated. The authors aimed to investigate the efficacy of botulinum toxin A injection at the Yonsei point for treating gummy smile. METHODS: In this double-blind, single-site, randomized clinical trial, healthy participants with a gummy smile (anterior gingival exposure of ≥3.0 mm) were enrolled and randomized (1:1 ratio) into two groups. The experimental group was administered 6 U of botulinum toxin A at the Yonsei point (a single-site injection of 3 U to the right Yonsei point and 3 U to the left Yonsei point), and the control group received the same dose in the bilateral levator labii superioris alaeque nasi muscle sites. The patients were assessed at baseline and 4, 12, 24, and 48 weeks after the first injection using a digital vernier caliper. RESULTS: A total of 49 participants were enrolled. Anterior and bilateral posterior gingival exposure were reduced at 4, 12, and 24 weeks ( P ≤ 0.05) and returned to baseline at 48 weeks in both groups; there was no difference between the groups at these time points. The increase in satisfaction among patients was significant, and few adverse events were observed. CONCLUSION: Both the Yonsei point and the levator labii superioris alaeque nasi muscle site can be used as botulinum toxin A injection sites for treating gummy smile. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.

Nerve to the zygomaticus major muscle: An anatomical study and surgical application to smile reconstruction.

Smile reconstruction using the branches that supply the zygomaticus major muscle as a motor source is an established procedure in facial reanimation surgery for facial paralysis. However, the anatomy of the nerve to the muscle remains unclear. Therefore, we herein examined the topographical anatomy of the nerve to the zygomaticus major muscle to obtain more detailed information on donor nerve anatomy. Preserved cadaver dissection was performed under a microscope on 13 hemifaces of 8 specimens. The branches that innervate the zygomaticus major muscle and their peripheral routes medial to the muscle were traced and examined. A median of four (ranges 2-4) branches innervated the zygomaticus major muscle. The proximal two branches (near the muscle origin) arose from the zygomatic branch, the second of which was the major branch. The distal branches (near the oral commissure) arose from the buccal branch or zygomaticobuccal plexus. The vertical distance from the caudal margin of the zygomatic arch to the major branch intersecting point was 19 ± 4.0 mm, while the horizontal distance parallel to the Frankfort plane was 29 ± 5.2 mm. The proximal two branches innervating the zygomaticus major muscle were detected in the majority of specimens. The anatomical findings obtained herein on the nerve to the zygomaticus major muscle will allow for more reliable donor selection in facial reanimation surgery.

Understanding the Relationship Between Facial Nerve Branch Sacrifice and Selective Neurectomy Outcome.

Introduction: While there is great interest in selective neurectomy (SN) for patients with synkinesis, outcomes can be inconsistent. Objective: To examine the relationships between intraoperative facial nerve branch transection and both postoperative outcome and functional deficits. Methods: SN cases, with minimal follow-up of 4 months, were retrospectively identified between 2019 and 2021; outcome was assessed using FaCE instrument, eFACE and Emotrics. Correlations between intraoperative facial nerve branch preservation or transection, and functional outcome and new functional deficits were examined. Results: Fifty-six cases were performed: 88% were females, and median age was 53 years (range 11-81). Mean follow-up was 19.5 months (range 4-42). Oral commissure excursion improved in patients where all smile branches were preserved, no vertical vector smile branches were transected, and more than three smile antagonist branches were transected. A linear trend between smile antagonist branch sacrifice and favorable smile outcome was found. Lower lip movement was improved in patients in whom more than half of the identified lower lip branches were transected. Thirty percent of patients experienced untoward postoperative functional deficits, from which 47% recovered with interventions. Conclusions: Several correlations between SN intra-operative decisions and outcome were identified; new or worsening functional deficit rate can be high. However, chemodenervation or fillers can help diminish these deficits.

Defining Standard Values for FaceReader Facial Expression Software Output.

BACKGROUND: FaceReader is a validated software package that uses computer vision technology for facial expression recognition which has become increasingly popular in academic research to expedite, scale, and decrease the cost of facial emotion analysis. In this study, we compare FaceReader analysis to human evaluator interpretation in order to define standard values for the software output. METHODS: Randomly generated facial images produced by generative adversarial networks were analyzed using FaceReader and by survey participants (n=496). The age, facial emotion, and intensity of emotion as determined by the software and survey participants were recorded. Results were analyzed and compared. RESULTS: 80 randomly generated images (20 children, 20 young adult, 20 middle aged, and 20 elderly; 38 male and 42 female) were included. Analysis of correlation between most common expression identified by FaceReader and the primary emotion detected by surveyors showed strong correlation (κ = 0.77, 95% CI = 0.64-0.91). On analyzing this correlation by age group, there was fair correlation in children (κ = 0.40, 95% CI = 0.078-0.72), perfect correlation in young adults (κ = 1.0, 95% CI = 1.0-1.0), strong correlation in middle aged adults (κ = 0.79, 95% CI = 0.53-1) and near perfect in elderly adults(κ = 0.9 , 95% CI = 0.7-1.0). CONCLUSIONS: We provided the first study defining the expected average values generated by FaceReader in generally smiling images. This can be used as a standard in future studies. LEVEL OF EVIDENCE IV: 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 .

Favorable Outcome Perception in Facial Selective Neurectomy.

OBJECTIVE: Facial selective neurectomy (SN) improves facial function by denervation of muscles antagonistic to the smile in nonflaccid facial paralysis (NFFP) patients. This study aims to assess whether and which objective facial function metrics affect favorable SN outcome in NFFP patients, as perceived by facial nerve (FN) practitioners. STUDY DESIGN: Retrospective cohort study. SETTING: NFFP patients who underwent SN at the facial nerve center. METHODS: Standardized preoperative and postoperative facial photographs of patients undergoing SN were analyzed using clinician-graded measures (eFACE) and automated facial measurement (Emotrics). Favorable outcome was ranked subjectively by 3 independent FN practitioners. Correlations between objective metrics and favorable subjective outcome were examined. RESULTS: Fifty-eight SN cases were included. Oral commissure excursion with smile, interlabial distance, and lower lip movement were all considered statistically significantly important for favorable outcome perception. Each +1 mm of smile excursion increases the odds of a favorable outcome by 75.4% (odds ratio [OR]: 1.754). Each +1 mm of interlabial distance asymmetry decreases the odds of a favorable outcome by 24.7% (OR: 0.753). Each +1-point change in lower lip movement eFACE score increases the odds of a favorable outcome by 2.7% (OR: 1.027). CONCLUSION: Several smile metrics contribute to favorable SN outcome perception among FN practitioners. Smile excursion, interlabial distance, and lower lip movement were significant predictors of success. These observations may be extrapolated to other facial reanimation interventions and serve surgeons and patients during counseling and expectation management, and during surgery.

Restoring the spontaneous smile through free functional muscle transfer. A systematic review and meta-analysis of the last twenty years' experience.

BACKGROUND: The recovery of the spontaneous smile has become a primary focus in facial reanimation surgery and its major determinant is the selected neurotizer. We aimed to compare the spontaneity outcomes of the most preferred neurotization methods in free functional muscle transfer for long-standing facial paralysis. METHODS: The Embase, Ovid Medline, and PubMed databases were queried with 21 keywords. All clinical studies from the last 20 years reporting the postoperative spontaneity rate for specified neurotization strategies [cross-face nerve graft (CFNG), contralateral facial nerve (CLFN), motor nerve to the masseter (MNM), and dual innervation (DI)] were included. A meta-analysis of prevalence was performed using Freeman-Tukey double arcsine transformation, I2 statistic, and generic inverse variance with a random-effects model. Risk Of Bias In Non-randomized Studies of Interventions and Newcastle-Ottawa scale were used to assess bias and study quality. RESULTS: The literature search produced 2613 results and 473 unique citations for facial reanimation. Twenty-nine studies including 2046 patients were included in the systematic review. A meta-analysis of eligible data (1952 observations from 23 studies) showed statistically significant differences between the groups (CFNG: 0.94; 95% confidence interval [CI], 0.76-1.00, CLFN: 0.91; 95% CI, 0.49-1.00, MNM: 0.26; 95% CI, 0.05-0.54, DI: 0.98; 95% CI, 0.90-1.00, P < 0.001). In pairwise comparisons, statistically significant differences were found between MNM and other neurotization strategies (P < 0.001 in CFNG compared with MNM, P = 0.013 for CLFN compared with MNM, P < 0.001 for DI compared with MNM). CONCLUSIONS: DI- and CLFN-driven strategies achieved the most promising outcomes, whereas MNM showed the potential to elicit spontaneous smile at a lower extent. Our meta-analysis was limited primarily by incongruency between spontaneity assessment systems. Consensus on a standardized tool would enable more effective comparisons of the outcomes.

The effect of various muscle transfer procedures on eye closure and blinking in longstanding facial palsy patients.

BACKGROUND: Facial palsy causes paralytic lagophthalmos, which remarkably deteriorates a patient's quality of life. In cases where denervation time is over 18-24 months (longstanding facial palsy), a free or pedicled muscle transfer is needed to replace the denervated orbicularis oculi muscle. PURPOSE: The purpose of this systematic review is to investigate the effect of various eye sphincter substitution procedures (free or pedicled muscle transfers) in longstanding facial palsy patients on eye closure and blink. METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we performed a systematic review of the Embase, Medline, Web of Science and Cochrane Library databases and Google Scholar. Our literature search yielded 4322 articles. Following a full-text review, 4 retrospective cohort studies and 21 case series were selected for this review. Meta-analyses using R package meta (version 6.5-0) were conducted. MAIN FINDINGS: All free and pedicled muscle transfers in this review showed an improvement in the scores and measurements on eye closure and blink. The pedicled temporalis muscle transfer was the procedure most commonly performed as eye reanimation surgery and showed consistent good results. Using the random effects model, the pooled effect of mean difference in lagophthalmos after gentle eye closure post-operatively versus pre-operatively (mm) in patients who received a pedicled (temporalis) muscle transfer was -6.19 (I2 = 85%, 95% CI: -7.89; -4.49) whereas it was -4.11 (I2 = 85%, 95% CI: -7.26; -0.95) for free (gracilis or platysma) muscle transfers. The pooled proportion of patients with complete eye closure after surgery was 0.69 (I2 = 49%, 95% CI: 0.54; 0.82) in patients who received a pedicled (temporalis) muscle transfer and 0.40 (I2 = 74%, 95% CI: 0.13; 0.74) in patients who received a free (platysma) muscle transfer. CONCLUSIONS: Unlike smile reanimation, dynamic eye closure and blink restoration are rather neglected topics in facial reanimation. The pedicled temporalis muscle transfer is often recommended as the first treatment of choice for eye reanimation in longstanding facial palsy patients since it is a reliable, straightforward procedure, that does not require complex microsurgery. However, with the advancements in the field of microsurgery, free muscle transfers are promising therapies, which may regenerate voluntary and spontaneous blinking.

Secondary dynamic midface reanimation with gracilis free muscle transfer after failed reconstruction attempt: A 15-year experience.

BACKGROUND: The quantitative outcome of secondary reanimation after a failed primary reconstruction attempt for facial paralysis is rarely reported in the literature. This study aimed to investigate the feasibility of secondary reanimation with gracilis free muscle transfer (GFMT) and whether this outcome is influenced by the primary reconstruction. METHODS: Twelve patients with previously failed static procedures (static group, n = 6), temporal muscle transfer (temporal transfer group, n = 2), and GFMT (GFMT group, n = 4) were all secondarily reanimated with GFMT. The clinical outcome was graded with the eFACE metric. The objective oral commissure excursion was measured with Emotrics, and the artificial intelligence software FaceReader evaluated the intensity score (IS) of emotional expression. RESULTS: The mean follow-up was 40 ± 27 months. The eFACE metric showed a statistically significant (p < 0.05) postoperative improvement in the dynamic and smile scores across all groups. In the GFMT group, oral commissure with smile (75.75 ± 20.43 points), oral commissure excursion while smiling with teeth showing (32.7 ± 4.35 mm), and the intensity of happiness emotion while smiling without teeth showing (IS of 0.37 ± 0.23) were significantly lower as compared with the static group postoperatively (98.83 ± 2.86 points, p = 0.038; 41.7 ± 4.35 mm, p = 0.025; IS 0.83 ± 0.16, p = 0.01). CONCLUSIONS: Our data suggest that secondary dynamic reconstruction with GFMT is feasible should the primary reconstruction fail. The secondary GFMT appears to improve the outcome of primary GFMT; however, the oral commissure excursion while smiling might be lower than that in patients who had static procedures as primary reconstruction.

Three-dimensional evaluation of symmetry in facial palsy reanimation using stereophotogrammetric devices: A series of 15 cases.

Facial palsy can severely compromise quality of life, significantly altering the harmony and symmetry of the face, which can be restored by surgical rehabilitation. The aim of the study was the quantification of facial symmetry following facial reanimation. Fifteen consecutive adult patients were surgically treated through triple innervation for reanimation of flaccid unilateral facial paralysis (contralateral facial nerve, masseteric nerve, and hypoglossal nerve) and fascia lata graft for definition of the nasolabial sulcus. In the preoperative stage and at least 11 months after the surgical treatment, three-dimensional facial images were recorded through stereophotogrammetry in a neutral (rest) position, and with Mona Lisa and full-denture (maximum) smiles. Labial commissure inclination relative to the interpupillary axis, and a surface assessment of local facial asymmetry at rest and while smiling were obtained for the upper, middle, and lower facial thirds. The angle between the interpupillary axis and the labial commissure significantly improved in post-surgical acquisitions, regaining symmetry at rest (t-test; p < 0.001). Facial symmetry increased significantly when passing from pre-to postsurgical facial scans, from the lower to the upper facial third, and from the full smile to the rest position (ANOVA; p < 0.001). After treatment, the full smile recovered more symmetry than the other two expressions. In summary, surgical treatment significantly reduced facial asymmetry, but this reduction differed significantly among the various animations and facial thirds. The results of this study confirmed clinical findings of significant static and dynamic improvements in facial symmetry after triple innervation reanimation surgery.

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.

P37-A124†Smile bank - corneal stromal lenticules from relex smile - the new eye bank product.

PURPOSE: The aim of our presentation is to introduce future eye bank product - corneal stromal lenticule from living donors, which can be used for allotransplantation. METHODS: ReLEx (refractive lenticule extraction) SMILE (small incision lenticule extraction) is a common approach in laser eye surgery. It is minimally invasive and flap-free procedure. During this procedure part of corneal stroma (lenticule) is created by femtosecond laser and consequently removed through small incision. The lenticule is basically waste material of the ReLEx SMILE procedure. In the International Eye Bank of Prague, we decided to establish new protocol for lenticule withdrawal, storage and release for transplantation. RESULTS: All donors signed an informed consent, and their serum was tested for the presence of infectious diseases. After ReLEx SMILE procedure the lenticule was stored in container with cryopreservation solution and frozen in the eye bank using the same protocol for frozen amniotic membrane. After 6 months in -80°C tissues were defrosted and examined histologically, using conventional light histology staining and electron microscopy. CONCLUSION: We believe, that lenticule from living donor is a safe and effective tissue, that can be used for many indications and in particular situations represents good alternative to whole donor cornea and amniotic membrane.

Triple nerve transfers for the management of early unilateral facial palsy.

BACKGROUND: Early onset facial paralysis is usually managed with cross-face nerve grafts, however the low number of axons that reach the target muscle may result in weakness or failure. Multiple-source innervation, or 'supercharging', seeks to combine the advantages of different donor nerves while minimizing their weaknesses. We propose a combination of cross-face nerve grafts with local extra-facial nerve transfers to achieve earlier facial reanimation in our patients. METHODS: A retrospective cohort including all patients with early unilateral facial palsy (<12 months evolution) who underwent triple nerve transfer between 2019 and 2021 was conducted. We performed single-stage procedure including zygomatic-to-zygomatic and buccal-to-buccal cross-face grafts, a nerve-to-masseter to bucozygomatic trunk transfer, and a mini-hypoglossal to marginal branch transfer. Results were evaluated using the clinician-graded facial function scale (eFACE). RESULTS: Fifteen patients were included (eight females, seven males), mean age at the time of surgery was 48.9 ± 13.3 years. Palsy was right-sided in eight cases. The mean time from palsy onset to surgery was 5.5 ± 2.8 months. Patients showed improvement in static (70.8 ± 21.9 vs. 84.15 ± 6.68, p = 0.002) and dynamic scores (20 ± 16.32 vs. 74.23 ± 7.46, p < 0.001), as well as periocular (57.33 ± 15.23 vs. 74 ± 7.18, p = 0.007), smile (54.73 ± 11.93 vs. 85.62 ± 3.86, p < 0.001), mid-face (46.33 ± 18.04 vs. 95 ± 7.21, p < 0.001) and lower face scores (67.4 ± 1.55 vs. 90.31 ± 7.54, p < 0.001). CONCLUSION: The triple nerve transfer technique using cross-face nerve grafts, the nerve-to-masseter, and the hypoglossal nerve, is an effective and reproducible technique to obtain middle and lower face reanimation in cases of early facial palsy.

Nerve guide conduits, nerve transfers, and local and free muscle transfer in facial nerve palsy.

PURPOSE OF REVIEW: To highlight the recent literature on reinnervation options in the management of facial nerve paralysis using nerve conduits, and nerve and muscle transfers. RECENT FINDINGS: Engineering of natural and synthetic nerve conduits has progressed and many of these products are now available on the market. The use of the masseter nerve has become more popular recently as a choice in nerve transfer procedures due to various unique advantages. Various authors have recently described mimetic muscle reinnervation using more than one nerve transfer, as well as dual and triple innervation of free muscle transfer. SUMMARY: The ideal nerve conduit continues to be elusive, however significant progress has been made with many natural and synthetic materials and designs tested and introduced on the market. Many authors have modified the classic approaches in motor nerve transfer, as well as local and free muscle transfer, and described new ones, that aim to combine their advantages, particularly the simplification to a single stage and use of multiple reinnervation to the mimetic muscles. These advances are valuable to the reconstructive surgeon as powerful tools that can be tailored to the unique challenges of patients with facial nerve palsy looking for dynamic reanimation options.

The impact of orthodontic-surgical treatment on facial expressions-a four-dimensional clinical trial.

OBJECTIVE: The objective of this clinical trial was to compare facial expressions (magnitude, shape change, time, and symmetry) before (T0) and after (T1) orthognathic surgery by implementing a novel method of four-dimensional (4D) motion capture analysis, known as videostereophotogrammetry, in orthodontics. METHODS: This prospective, single-centre, single-arm trial included a total of 26 adult patients (mean age 28.4 years; skeletal class II: n = 13, skeletal class III: n = 13) with indication for orthodontic-surgical treatment. Two reproducible facial expressions (maximum smile, lip purse) were captured at T0 and T1 by videostereophotogrammetry as 4D face scan. The magnitude, shape change, symmetry, and time of the facial movements were analysed. The motion changes were analysed in dependence of skeletal class and surgical movements. RESULTS: 4D motion capture analysis was feasible in all cases. The magnitude of the expression maximum smile increased from 15.24 to 17.27 mm (p = 0.002), while that of the expression lip purse decreased from 9.34 to 8.31 mm (p = 0.01). Shape change, symmetry, and time of the facial movements did not differ significantly pre- and postsurgical. The changes in facial movements following orthodontic-surgical treatment were observed independently of skeletal class and surgical movements. CONCLUSIONS: Orthodontic-surgical treatment not only affects static soft tissue but also soft tissue dynamics while smiling or lip pursing. CLINICAL RELEVANCE: To achieve comprehensive orthodontic treatment plans, the integration of facial dynamics via videostereophotogrammetry provides a promising approach in diagnostics. TRIAL REGISTRATION NUMBER: DRKS00017206.

Age-related outcomes of facial reanimation surgery using gracilis free functional muscle transfer innervated by the masseteric nerve: A retrospective cohort study.

BACKGROUND: The free functional muscle gracilis transfer is an established approach in facial reanimation surgery; however, the significance of its neurotization and the patient's age is still inconclusive. Several donor nerves are available for facial reanimation using the free functional gracilis muscle transfer. OBJECTIVE: This retrospective cohort study investigates whether the masseteric nerve is an equally reliable donor nerve in both older and younger patients. METHODS: We included 46 patients (13-71 years, male and female) who underwent nerve-to-masseter (NTM)-driven free functional muscle transfer (FFMT) between January 2008 and December 2019. Patients were distributed into three cohorts according to their age at surgery. We assessed the facial symmetry before and after surgery using the pupillo-modiolar angle. Commissure height and excursion deviation were measured with the Emotrics software. Patient-reported outcome measurements were taken using the Facial Clinimetric Examination (FaCE) scale. RESULTS: All patients had successful flap innervation, except for one patient in the middle-aged cohort (31-51 years). The postoperative facial symmetry at rest, smiling, and laughing was analyzed with the pupillo-modiolar angle and the Emotrics software and showed similar results between all cohorts. The FaCE scale showed similar scores for the middle-aged (31-51 years) cohort and the senior cohort (52-71 years). The social function score in the senior cohort was higher than in the middle-aged cohort, without statistical significance. One patient in the middle-aged (31-51 years) cohort and the senior cohort (52-71 years), respectively, underwent emergency revision due to impaired flap perfusion and could be salvaged. CONCLUSIONS: NTM-driven FFMT for facial reanimation is a safe and reliable procedure across all age groups of patients.