Síndrome del incisivo central maxilar único: reporte de caso

El síndrome del incisivo central maxilar único es una rara alteración en el desarrollo y formación de órganos ubicados principalmente en la línea media; el cual ocurre de manera temprana entre los días 35 al 38 de vida intrauterina. Su etiología es desconocida, aunque se ha asociado a deleciones de los cromosomas 7 (7q.36.1) y 8, y a mutaciones en el gen Sonic Hedgehog. Presenta una prevalencia de 1/50.000 nacidos vivos y aunque es una anomalía poco frecuente del desarrollo craneofacial, su diagnóstico y tratamiento temprano son importantes para los odontólogos generales o especialistas ya que puede ser un signo de otras anomalías congénitas o del desarrollo graves. Por lo tanto, el objetivo de este caso es reportar la fase inicial de tratamiento en un niño con el síndrome de incisivo central maxilar único quien no había sido diagnosticado anteriormente con este síndrome. Caso Clínico: Paciente masculino de 10 años de edad, procedente de Jamundí, Valle del Cauca- Colombia. Reporta ausencia de órgano dentario superior. En el examen intraoral se observa un incisivo central único sobre la línea media del maxilar, ausencia de frenillo labial y papila incisiva, paladar oval y retrognatismo mandibular. Fue tratado en una primera fase con ortopedia funcional maxilar para mejorar la clase II y está a la espera de iniciar la segunda fase de tratamiento con ortodoncia. Conclusiones: El síndrome de incisivo central maxilar único es un síndrome poco frecuente el cual conlleva múltiples afecciones que interfieren en el normal desarrollo y crecimiento de estructuras anatómicas.

A síndrome do incisivo central superior único é uma alteração rara no desenvolvimento e formação de órgãos localizados principalmente na linha média; que ocorre precocemente entre os dias 35 a 38 de vida intrauterina. Sua etiologia é desconhecida, embora tenha sido associada a deleções dos cromossomos 7 (7q.36.1) e 8, e mutações no gene Sonic Hedgehog. Tem uma prevalência de 1/50.000 nascidos vivos e, embora seja uma anomalia rara do desenvolvimento craniofacial, seu diagnóstico e tratamento precoces são importantes para dentistas gerais ou especialistas, pois pode ser sinal de outras anomalias congênitas ou de desenvolvimento graves. Portanto, o objetivo deste caso é relatar a fase inicial do tratamento em uma criança com síndrome do incisivo central superior único que não havia sido previamente diagnosticada com essa síndrome. Caso clínico: Paciente do sexo masculino, 10 anos, procedente de Jamundí, Valle del Cauca- Colômbia. Relata ausência de órgão dentário superior. O exame intraoral mostra um único incisivo central na linha média maxilar, ausência de frênulo labial e papila incisiva, palato oval e retrognatismo mandibular. Foi tratado numa primeira fase com ortopedia funcional maxilar para melhorar a classe II e aguarda para iniciar a segunda fase do tratamento ortodôntico. Conclusões: A síndrome do incisivo central superior único é uma síndrome rara que envolve múltiplas condições que interferem no desenvolvimento e crescimento normal das estruturas anatômicas.

Solitary maxillary central incisor syndrome is a rare alteration in the development and formation of organs located mainly in the midline; which occurs early between days 35 to 38 of intrauterine life. Its etiology is unknown, although it has been associated with deletions of chromosomes 7 (7q.36.1) and 8, and mutations in the Sonic Hedgehog gene. It has a prevalence of 1/50,000 live births and although it is a rare anomaly of craniofacial development, its early diagnosis and treatment are important for general dentists or specialists since it can be a sign of other serious congenital or developmental anomalies. Therefore, the objective of this case is to report the initial phase of treatment in a child with solitary maxillary central incisor syndrome who had not been previously diagnosed with this syndrome. Clinical case: Male patient, 10 years old, from Jamundí, Valle del Cauca- Colombia. Reports absence of upper dental organ. Intraoral examination shows a solitary central incisor on the maxillary midline, absence of labial frenulum and incisive papilla, oval palate and mandibular retrognathism. He was treated in a first phase with maxillary functional orthopedics to improve class II and is waiting to start the second phase of orthodontic treatment. Conclusions: Solitary maxillary central incisor syndrome is a rare syndrome which involves multiple conditions that interfere with the normal development and growth of anatomical structures.

Research progress on the regulation of craniofacial development and malformation by fibroblast growth factor 8 / 口腔疾病防治

@#Fibroblast growth factor 8 (FGF8) is a kind of secretory polypeptide that has crucial roles in the development of various tissues and organs. Current studies have found that FGF8 can regulate the differentiation of cranial neural crest cells by activating the mitogen-activated protein kinase (MAPK) signaling pathway and affect the establishment of mandibular arch polarity and the development of craniofacial symmetry by regulating the expression of target genes. Cleft lip with or without cleft palate, ciliopathies, macrostomia and agnathia are four developmental malformations involving the craniofacial region that seriously affect the quality of life of patients. The abnormal FGF8 signal caused by gene mutation, abnormal protein conformation or expression is closely related to the occurrence of craniofacial malformations, but the molecular mechanism and signaling pathway underlying these malformations have not been fully elucidated. Craniofacial development is a complex process mediated by a variety of signaling molecules. In the future, the role of various signaling molecules in craniofacial development and malformations need to be explored to provide a new perspective and vision for the prevention and treatment of these craniofacial malformations.

Pathogenic genes and clinical therapeutic strategies for Treacher Collins syndrome / 华西口腔医学杂志

Treacher Collins syndrome is a congenital craniofacial malformation with autosomal dominant inheritance as the main genetic pattern. In this condition, the biosynthesis of ribosomes in neural crest cells and neuroepithelial cells is blocked and the number of neural crest cells that migrate to the craniofacial region decreases, causing first and second branchial arch dysplasia. Definite causative genes include treacle ribosome biogenesis factor 1 (tcof1), RNA polymerase Ⅰ and Ⅲ subunit C (polr1c), and RNA polymerase Ⅰ and Ⅲ subunit D (polr1d). This paper provides a review of research of three major patho-genic genes, pathogenesis, phenotypic research, prevention, and treatment of the syndrome.

The development and recent status of the craniomaxillofacial surgery in China during past three decades / 中国修复重建外科杂志

The authors made a profound review on the development and the recent status of craniomaxillofacial surgery in China during past three decades. The emphases were placed on the following aspects: the modifications of the reconstructive procedure and minimal invasive mode, the researches on molecular genetic characteristics of the congenital craniofacial malformations, the clinical applications of three-dimensional digital computer-aided techniques (including three-dimensional printing and prefabricated template for precious osteotomies), the craniomaxillofacial defects reconstructing by using the distraction osteogenesis and osseous integrated titanium implant and prothesis, etc. Finally, the authors outlooked prospectively the future trends of the craniomaxillofacial surgery.

A Case of Apert Syndrome with a P253R Mutation on FGFR2 Exon VIII

Apert syndrome is a rare congenital anomaly characterized by craniofacial malformations and severe symmetrical syndactyly of fingers and toes. This syndrome is caused by a genetic mutation; the S253 mutation is common, though the P253R mutation is not as frequent. Common symptoms include skeletal malformations, poor joint mobility, eye and ear problems, cleft palate, and orthodontic and other dental problems. We report a case of an infant with the common morphological features of Apert syndrome. Interestingly, she was found to have the P253R mutation in FGFR2 exon VIII, which has been less commonly observed in Korea. A brief review of the literature is included.