Aesthetic restoration in maxillo-mandibular malformations: the role of genioplasty

Aim: The aim of this study was to determinate how orthognatic surgery aids to cure many skull and face abnormalities and to help re-establishing the correct occlusive relation thanks to the repositioning of the maxillo-mandibular skeleton basis. Methods: The study included 183 male patients and 338 female patients, with an average age of 23 years. The sample series was divided according to specific pathologies. All patients underwent surgical procedures and the therapeutic strategy was determined based on the anomalies presented. Results: 113 patients had a II class dental skeletal occlusion, 180 patients had a III class dental-skeletal occlusion and 222 patients had skull-facial abnormalities. 5 patients underwent only a genioplasty, 82 patients underwent a genioplasty associated with BSSO, 175 patients underwent a genioplasty associated with Le Fort I osteotomy and the remaining 253 patients underwent a genioplasty associated with BSSO and Le Fort I osteotomy. Conclusion: The experience shows that genioplasty has been successfully introduced in orthognathic surgical therapeutic procedures, for dental-skeleton abnormalities and mandibular asymmetries treatment. In recent years, the evolution of computer systems has allowed an accurate assessment and programming, by means of the three-dimensional display, which are of great help in the course of diagnosis and evaluation of the displacements to be carried out, in order to obtain optimal aesthetic results

Genioplasty with surgical guide using 3D-printing technology : a systematic review

The purpose of this systematic review is to evaluate the current state of the art of making genioplasties using 3D printing technology. A multi-database single-reviewer systematic review identified sixteen papers that fulfilled the selection criteria. There were mainly case series and case reports available (Level IV of the Oxford Evidence-based medicine scale); only two prospective study (Level III) evaluated this subject. These articles are analyzed in details and summarized in this review. The realization of genioplasties with surgical guide using 3D-printing technology could improve predictability and accuracy. It protects anatomical structures in the environment of the surgery, reducing by this way the morbidity and providing safer results. The type of printer and material used as well as the sterilization techniques should be further developed by the authors. The use of open-access software should also be further explored to allow the use of these new technologies by the largest number of surgeons. Finally, prospective multi-center studies with larger samples should be performed to definitively conclude the benefits of this new technology and allow for its routine use. This article is the first systematic review on this topic

Analysis of Soft Tissue Changes after Genioplasty in Skeletal Class III Dentofacial Deformity

Purpose: The purpose of this study was to measure the anteroinferior changes and the degree of vertical changes to facilitate the prediction of treatment outcome in patients undergoing genioplasty only, genioplasty with bilateral sagittal split ramus osteotomy (BSSRO), genioplasty, or BSSRO and Lefort I osteotomy. Materials and Methods: Serial cephalometry was performed on 25 patients at 1-year follow-up after genioplasty, to assess skeletal changes and relapse. Surgery was performed using conventional techniques. Results: The mean ratio was 0.9: 1 of soft tissue to skeletal movement at pogonion, but the average difference between hard and soft tissue was large; thus, the prediction of anteroposterior soft tissue changes was quite inaccurate. Conclusion: We observed a good correlation between the amount of hard versus soft tissue change with surgery in the horizontal direction, but a poor correlation in the vertical plane. Key Words: Soft tissue changes, genioplasty, skeletal class III dentofacial deformit

Main clinical approaches to orthognathic surgery for class II open bite and genioplasty patients: a brief systematic review

Introduction: Orthognathic surgery (OS) is used to improve the patient's facial appearance and to correct maxillary and mandibular deformities resulting from malocclusions, disease, or trauma. In this context, genioplasty is a procedure to correct an aesthetic and functional deformity of the chin region, improving the contour. Moreover, anterior open bite (AOB) is the lack of vertical contact or negative overbite between the anterior teeth of the superior and inferior arches when the posterior teeth are in occlusion. Objective: The present study aimed to perform a brief systematic review with risk of bias analysis by funnel plot to highlight the main clinical approaches of orthognathic surgery in class II patients with open bites and also concerning genioplasty. Methods: The research was carried out from February 2022 to May 2022 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 115 articles were found. In total, 57 articles were fully evaluated and 34 were included and evaluated in this study. And of the total of 34 articles, only 11 articles were developed as the main clinical results. A total of 32 articles were excluded because they did not meet the GRADE classification, and 16 were excluded because they were at risk of bias. The symmetric funnel plot does not suggest a risk of bias between the small sample size studies. A retrospective observational study compared 57 patient charts on treatment outcomes for anterior occlusion and vertical skeletal stability after maxillary or mandibular surgery to correct Class II malocclusion with a mild to moderate open bite. After surgery, 87% of Le Fort I patients and 63% of patients with bilateral sagittal split osteotomy had a positive overbite, and at the 6-month follow-up, the percentages were 90% and 74%, respectively. Another study showed Class II patients had significantly greater amounts of lateral and lower translation than class III patients. Also, genioplasty represents one of the most common auxiliary procedures and may be associated with corrective surgery for dentofacial dysmorphisms. However, care must be taken with mental nerve injuries, asymmetries, and intraoperative bleeding are the main immediate complications

양악 악교정수술과 수술 교정치료를 받은 골격성 III급 부정교합 환자의 측모 두부계측방사선사진 영상에서 인공지능을 이용한 경조직 계측점 식별 시 평균 오차의 변화 양상

학위논문(박사) -- 서울대학교대학원 : 치과대학 치의과학과, 2022. 8. 백승학.Objective: Recently, auto digitization of hard tissue landmarks on lateral cephalograms (Lat-cephs) has reported, with regard to artificial intelligence models using cascade convolutional neural network (CNN). The aim of this study was to investigate the pattern of accuracy change in artificial intelligence (AI)-assisted hard tissue landmark identification in serial Lat-cephs of Class III patients who underwent two-jaw orthognathic surgery and orthodontic treatment using a cascade CNN algorithm. Materials and Methods: A total of 3,188 Lat-cephs of 797 Class III patients were allocated into the training and validation sets (3,004 Lat-cephs of 751 patients) and test set (184 Lat-cephs of 46 patients; subdivided into the genioplasty and non-genioplasty groups, n=23 per group) for landmark identification using a cascade CNN model. Each Class III patient in the test set had four Lat-cephs: initial (T0), pre-surgery [T1, presence of orthodontic brackets (OBs)], post-surgery [T2, presence of OBs and surgical plates and screws (SPS)], and debonding [T3, presence of SPS and fixed retainers (FR)]. After mean errors of 20 hard tissue landmarks between human gold standard and the cascade CNN model were calculated, statistical analysis was performed. Results: Results are as follows. (1) The total mean error was 1.17 mm without significant difference among the four time-points (T0, 1.20 mm; T1, 1.14 mm; T2, 1.18 mm; T3, 1.15 mm). (2) In comparison of two time-points [(T0, T1) vs. (T2, T3)], ANS, A point, and B point showed an increase in error (P<0.01; P<0.05; P<0.01), while distal contact point of the maxillary first molar (Mx6D) and distal contact point of the mandibular first molar (Md6D) showed a decrease in error (P<0.01; P<0.01). (3) No difference in errors existed at B point, Pogonion, Menton, crown tip of the mandibular central incisor (Md1C), and root apex of the mandibular central incisor (Md1R) between the genioplasty and non-genioplasty groups. Conclusion: The cascade CNN model can be used for auto-digitization of hard tissue landmark in serial Lat-cephs including initial, pre-and post-surgery, and debonding time points despite presence of OB, SPS, FR, genioplasty, and bone remodeling.연구목적: 최근 직렬 합성곱 신경망 (cascade TJneural network) 인공지능 모델을 사용하여 측모두부계측방사선사진 영상에서 경조직 계측점을 자동 식별(auto-digitization)하는 연구들이 발표되고 있다. 본 연구의 목적은 양악 악교정수술과 술전 및 술후 교정치료를 받은 환자들의 연속적인 측모두부계측방사선사진 영상에서 경조직 계측점을 자동 식별하는 정확도가 촬영 시점에 따라 어떠한 양상으로 변화하는 지 평가하는 것이었다. 연구재료 및 방법: 연구 대상은 양악 악교정 수술을 받은 골격성 III급 부정교합 환자 797명의 측모두부계측방사선사진 영상 3,188장이었다. 751명으로부터 확보한 3,004장의 영상을 training set과 validation set으로 활용하였고, 46명 환자 [이부성형술(genioplasty) 시행 군 (n=23), 이부성형술(genioplasty) 비시행군 (n=23)]로부터 확보한 184장의 영상을 test set으로 하였다. Test set은 초진(T0), 교정용 브라켓 영상이 포함된 술전(T1), 수술용 고정판과 나사 (surgical plate and screw) 영상이 나타난 술후(T2), 수술용 고정판과 나사 및 고정식 유지장치가 영상으로 보이는 종료(T3)의 4가지 시점별로 촬영된 측모두부계측방사선사진 영상으로 구성되었다. 인공지능과 치과교정과 전문의1인(human gold standard)이 각각 20개의 경조직 계측점을 digitization 한 후, 이에 따른 오차를 통계적으로 검증하였다. 연구 결과: 그 결과는 다음과 같았다. (1) 전체 평균 오차는 1.17 mm, T0의 평균 오차는 1.20 mm, T1의 평균 오차는 1.14 mm, T2의 평균 오차는 1.18 mm, T3의 평균 오차는 1.15 mm로 나타났다. (2) 술전(T0, T1)과 술후(T2, T3)의 비교에서는, ANS, A point, B point 의 오차가 통계학적으로는 증가하였으나 임상적으로는 유의미하지 않았고 (P<0.01; P<0.05; P<0.01), Mx6D와 Md6D는 오차가 감소하였다 (P<0.01; P<0.01). (3) genioplasty 실행군과 genioplasty 비실행군 간의 비교에서 B point, Pogonion, Menton, Md1C, Md1R의 오차는 통계적인 차이가 나타나지 않았다. 결론: 직렬 인공지능 합성곱 신경망 모델은 교정 브라켓, 수술용 고정판과 나사, 고정식 유지장치, 이부성형술 그리고 수술 후 골 개조에도 불구하고, 초진, 술전 교정 치료, 술후 교정치료, 종료 시 촬영된 측모두부계측방사선사진 영상에서 경조직 계측점들을 자동식별 하는데 사용될 수 있다는 결론을 도출하였다.I. INTRODUCTION 1 II. REVIEW OF LITERATURE 3 III. MATERIALS AND METHODS 10 IV. RESULTS 14 V. DISCUSSION 17 VI. CONCLUSIONS 23 REFERENCES 25 Tables 28 Figures 36 국문초록 42박

Sobre cirugía del mentón (Genioplastía)

Facial harmony is the consequence of a proper balance between all facial structures. The identification and classification of morphologic characteristics that detract from facial harmony is most effectively accomplished by clinical examination. The maintenance of the ratios between the facial thirds, correct spatial bone position and soft tissues accommodation are all factors that directly contribute in a balanced facial profile. The chin, likewise, contributes significantly in facial balance, mainly in the profile view. Expressive changes on chin position are associated with the perception of strong or delicate characters. Thus, over the years, a series of studies has been constructed focusing on mandibular osteotomies techniques that enable changes in chin position: advances, setback, extrusion, intrusion, widening, narrowing and asymmetry. This study aims to address historical and technical aspects of genioplasty; associating patient's condition with the surgical techniques that can be applied for correction of chin deformities384La armonía facial es la consecuencia del balance entre las estructuras facial. La identificación y clasificación de las características morfológicas que están acompañando la armonía facial son mas efectivas al realizar un estudio de análisis facial. La obtención de promedios entre los tercios, corrección especial de la posición del hueso y la acomodación de los tejidos blandos son factores directamente involucrados en el balance del perfil. El mentón, contribuye significativamente en este balance. Cambios expresivos en la posición del mentón son asociados con la percepción de características fuertes o delicadas. Durante los años, una serie de estudios han sido desarrollados enfocándose en las osteotomías mandibulares y técnicas capaces de alcanzar los cambios en la posición del mentón: avances, retrocesos, extrusiones, ensanchamientos, estrechamientos y asimetrías. Este estudio pretende orientar las condiciones históricas y técnicas respecto de la genioplastia; la asociación de las características del paciente con la técnica quirúrgica pueden ser aplicadas para la corrección de las deformidade

Modified Le Fort I Osteotomy and Genioplasty for Management of Severe Dentofacial Deformity in β-Thalassaemia Major: Case report and review of the literature

β-thalassaemia major is an autosomal recessive form of haemoglobinopathy that is characterised by complete lack of production of the β-chains resulting in multiple complications that include severe anaemia, failure to thrive and skeletal abnormalities. Facial deformities induced by β-thalassaemia major are rare and are very challenging to treat from a surgical point of view. We report a 33-year-old female patient with β-thalassaemia major who presented to the Dental &amp; Maxillofacial Surgery Department, Sultan Qaboos University Hospital, Muscat, Oman, in 2017 with gross dentofacial skeletal deformity contributing to her psychosocial issues. The facial deformity was corrected surgically by excision of the enlarged maxilla, modified Le Fort I osteotomy and advancement genioplasty. This case highlights the pre-operative preparation, surgical management, encountered complications and treatment outcome within 24 months of follow-up.Keywords: Beta-Thalassaemia; Thalassaemia Major; Cooley's Anemia; Le Fort Osteotomy; Genioplasty; Dentofacial Deformities; Case Report; Oman

Innovation in prediction planning for anterior open bite correction

This study applies recent advances in 3D virtual imaging for application in the prediction planning of dentofacial deformities. Stereo-photogrammetry has been used to create virtual and physical models, which are creatively combined in planning the surgical correction of anterior open bite. The application of these novel methods is demonstrated through the surgical correction of a case

Surgical ciliated cyst after a mandibular surgery: a particular case report and review of the literature

[EN] Background: Surgical ciliated cyst is a rare clinicopathological lesion that appears in patients who undergo maxillofacial surgery. In this report we present a particular mandibular case and we discuss the etiopathogenesis and clinicopathological features of this pathology after reviewing the current literature, as well as the origin of its respiratory epithelial profile. Case presentation: The patient is a 67-year-old male with an irregular radiolucency in a previously tooth extracted area of the mandible. The histopathological study revealed a cystic lesion with a connective wall with chronic inflammation, partially lined by a ciliated pseudostratified epithelium. PAS and CK19 stains showed the respiratory characteristics of this epithelium and confirmed the final diagnosis of mandibular surgical ciliated cyst. Conclusions: Surgical ciliated cyst is an uncommon entity associated with maxillofacial surgical procedures with bone and nasal cartilage grafts. In our case, treatment with growth factors present in platelet-rich plasma could explain the respiratory changes observed in the cystic epithelial lining.