Correction of asymmetric facial deformity by contouring: indications and outcomes.
Liao Lijun,Hsu Yuchun,Hu Jing,Li Xiang,Li Hui,Li Jihua
The Journal of craniofacial surgery
BACKGROUND:Facial asymmetry is usually due to unbalanced development of the lower jaw and zygoma and often results in esthetically unpleasant appearance. However, reasonable and systematic treatment of such an asymmetric face is rarely reported in the literature. This article aims to evaluate the effectiveness of surgical correction of asymmetric facial deformity and discuss their indications. METHODS:From July 2006 to November 2010, a total of 52 patients received contour reshaping procedures to correct their asymmetric faces. Those patients in whom the asymmetric facial deformities were initiated by hypertrophy of the mandible and zygoma without occlusion and temporomandibular joint problem were chosen for this study. The authors performed a modified reduction malarplasty to correct asymmetric middle face and mandibular outer cortex splitting ostectomy, mandibular "V-line" ostectomy, and rotation genioplasty to improve asymmetric lower face depending on individual asymmetric facial characteristics. The effectiveness was then evaluated through cephalometric radiographs, three-dimensional computed tomography, and presurgical and postsurgical standard facial photographs. RESULTS:The postoperative results of all 52 cases showed that the asymmetric face was effectively corrected without serious complications and the harmonious facial contour improved significantly. The final esthetic outcomes were quite satisfactory for both surgeons and patients. CONCLUSIONS:The results indicate that a variety of contouring techniques for facial asymmetric deformity could be carried out based on characteristics of asymmetric face, so as to acquire a symmetric and harmonious face in accordance with facial esthetics.
10.1097/SCS.0000000000001026
The accuracy of soft tissue movement using virtual planning for non-syndromic facial asymmetry cases-a systematic review.
Oral and maxillofacial surgery
The 3D prediction of post-operative changes is an inevitable tool for the surgical correction of facial asymmetry. The objective is to execute an evidence-based review answering the following question. Does the 3D virtual prediction planning draw reliable and accurate results in the surgical outcome related to the soft tissues of the face in facial asymmetry? This systematic review of the literature is based on the 3D soft tissue prediction planning of facial asymmetry correction to draw conclusions on the reliability and accuracy of these methods in the surgical outcome related to the soft tissues of the face. PubMed, Web of Science, Cochrane, and Ovid databases were adopted for the literature search. Studies published between years 2000 and 2020, aimed at the assessment of soft tissue predictions using software prediction packages for facial asymmetry, were selected. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) was applied. Quadas-2 tool was used for the qualitative evaluation of selected studies. Initial search yielded 248 articles. Twenty articles fulfilled the inclusion and exclusion criteria and selected for qualitative analysis. Finally, 12 articles were selected for quantitative analysis. The results indicate 3D imaging prediction methods provided more accurate information with less distortion for soft tissue prediction regardless of various softwares currently available. The prediction of soft tissue accuracy in facial asymmetry was less accurate in lower face regardless of the type of surgery for facial asymmetry. The mean prediction error was less than 2 mm.
10.1007/s10006-022-01059-w
Exploring Progression and Differences in Facial Asymmetry for Hemifacial Microsomia and Isolated Microtia: Insights from Extensive 3D Analysis.
Aesthetic plastic surgery
BACKGROUND:Aiming to measure and compare asymmetry of facial hard and soft tissues in patients with HFM and isolated microtia, examining how it evolves. METHODS:This cross-sectional study assessed facial asymmetry in male East Asian patients aged 5-12 diagnosed with unilateral hemifacial microsomia (Pruzansky-Kaban types I and IIA) or isolated microtia. Using 3D imaging of computed tomography scans, it measured root-mean-square (RMS) values for surface deviations across facial regions. Statistical analyses explored differences between conditions and the relationship of age with facial asymmetry. RESULTS:A total of 120 patients were categorized into four groups by condition (HFM or isolated microtia) and age (5-7 and 8-12 years). Patients with HFM exhibited the greatest asymmetry in the lower cheek, while those with isolated microtia showed primarily upper face asymmetry. Significant differences, except in the forehead and nasal soft tissue, were noted between the groups across age categories. Notable distinctions in hard tissue were found between age groups in the nasal and mid-cheek areas for patients with HFM (median RMS (mm) 0.9 vs. 1.1, P = 0.02; 1.5 vs. 1.7, P = 0.03) and in the nasal and upper lip areas for patients with isolated microtia (median RMS (mm) 0.8 vs. 0.9, P = 0.002; 0.8 vs. 1.0, P = 0.002). Besides these areas for HFM, no significant age-asymmetry correlation was detected. CONCLUSIONS:Significant differences in facial asymmetry were observed between HFM and isolated microtia, with the asymmetry in specific area evolving over time. 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 .
10.1007/s00266-024-04246-0
Esthetic rehabilitation through crown lengthening and laminate veneers. A digital workflow
The international journal of esthetic dentistry
AIM:To describe a digital workflow utilizing 3D printing technology to guide esthetic crown lengthening and control tooth preparation. CLINICAL CONSIDERATIONS:After the initial intraoral and face scans, an esthetic treatment plan was performed digitally based on the patient's personality and face type using artificial intelligence-based 3D smile design software. A 3D-printed tray relined with silicone over a 3D-printed model was used for the mock-up. A 3D-printed guide was implemented to assist esthetic crown lengthening by incorporating, simultaneously, information about the desired free gingival line and the alveolar bone level. Based on the initial planning, a set of reduction guides was 3D printed to check and correct the tooth preparation. Prior to the start of construction of the final monolithic restorations, their design was verified using 3D-printed prototypes. A stabilization splint was digitally designed and 3D printed to protect and maintain the final result. CONCLUSIONS:Technologic advances can improve the predictability of an interdisciplinary esthetic approach. Digital planning can be transferred to clinical reality using a digital workflow, utilizing a set of appropriate 3D-printed guides, which can help to control clinical procedures based on the initial planning. CLINICAL SIGNIFICANCE:By following the proposed step-by-step workflow, clinicians can achieve predictable results through an interdisciplinary approach, guiding both the periodontal plastic surgery and the restorative treatment after an individualized CAD/CAD procedure for 3D-printed guides.
3D facial mask for facial asymmetry diagnosis.
Heliyon
Objectives:Facial asymmetry is a common problem seen in orthodontic clinics that may affect patient esthetics. In some instances, severe asymmetry that affects patient esthetics may cause psychological issues. An objective method is therefore required to help orthodontists identify asymmetry issues. Materials and methods:We used three-dimensional (3D) facial images and landmark-based anthropometric analysis to construct a 3D facial mask to evaluate asymmetry. The landmark coordinates were transformed using a symmetric 3D face model to evaluate the efficacy of this method. Patients with facial asymmetry were recruited to conduct mirror and overlap analysis to form color maps, which were used to verify the utility of the novel soft tissue landmark-based method. Results:The preliminary results demonstrated that the asymmetry evaluation method had a similar response rate compared to diagnosis using mirror and overlap 3D images, and could therefore identify 3D asymmetry problems. Conclusions:By using 3D facial scans and 3D anthropometric analysis, we developed a preliminary evaluation method that provides objective parameters to clinically evaluate patient facial asymmetry and aid in the diagnosis of asymmetric areas. Clinical relevance:This study presents a novel facial asymmetry diagnostic method that has the potential to aid clinical decisions during problem identification, treatment planning, and efficacy evaluation.
10.1016/j.heliyon.2024.e26734
Direct 3D Printing of Clear Orthodontic Aligners: Current State and Future Possibilities.
Tartaglia Gianluca M,Mapelli Andrea,Maspero Cinzia,Santaniello Tommaso,Serafin Marco,Farronato Marco,Caprioglio Alberto
Materials (Basel, Switzerland)
The recent introduction of three-dimensional (3D) printing is revolutionizing dentistry and is even being applied to orthodontic treatment of malocclusion. Clear, personalized, removable aligners are a suitable alternative to conventional orthodontic appliances, offering a more comfortable and efficient solution for patients. Including improved oral hygiene and aesthetics during treatment. Contemporarily, clear aligners are produced by a thermoforming process using various types of thermoplastic materials. The thermoforming procedure alters the properties of the material, and the intraoral environment further modifies the properties of a clear aligner, affecting overall performance of the material. Direct 3D printing offers the creation of highly precise clear aligners with soft edges, digitally designed and identically reproduced for an entire set of treatment aligners; offering a better fit, higher efficacy, and reproducibility. Despite the known benefits of 3D printing and the popularity of its dental applications, very limited technical and clinical data are available in the literature about directly printed clear aligners. The present article discusses the advantages of 3D printed aligners in comparison to thermoformed ones, describes the current state of the art, including a discussion of the possible road blocks that exist such as a current lack of approved and marketed materials and limited existence of aligner specific software. The present review suggests the suitability of 3D direct printed aligners is superior to that of thermoformed manufactured aligners because of the prior's increased accuracy, load resistance, and lower deformation. It is an overall more stable way to produce an aligner where submillimeter movements can make a difference in treatment outcome. Direct 3D printing represents a complex method to control the thickness of the aligner and therefore has a better ability to control the force vectors that are used to produce tooth movement. There is currently no other approved material on the market that can do this. The conclusion of this article is that we encourage further in vitro and in vivo studies to test these new technologies and materials.
10.3390/ma14071799