Meta-analysis of the efficacy of invisible orthodontic appliances for maxillary molar distalization in adult patients / 口腔疾病防治

Objective@#To evaluate the clinical efficacy of invisible orthodontic appliances without brackets for the distal movement of maxillary molars to improve the ability of orthodontists to predict treatment outcomes.@*Methods@#Web of Science, Cochrane Library, Embase, PubMed, Wanfang Database, CNKI Database, and VIP Database were searched for studies investigating the efficacy of invisible orthodontic appliances for distal movement of maxillary molars in adult patients and published from database inception to August 1, 2023. A total of three researchers screened the studies and evaluated their quality and conducted a meta-analysis of those that met quality standards.@*Results@#This study included 13 pre- and postcontrol trials with a total sample size of 281 patients. The meta-analysis revealed no significant differences in the sagittal or vertical parameters of the jawbone after treatment when compared with those before treatment (P>0.05). The displacement of the first molar was MD=-2.34, 95% CI (-2.83, -1.85); the displacement was MD=-0.95, 95% CI (-1.34, -0.56); and the inclination was MD=-2.51, 95% CI (-3.56, -1.46). There was a statistically significant difference in the change in sagittal, vertical, and axial tilt of the first molar before and after treatment. After treatment, the average adduction distance of the incisors was MD=-0.82, 95% CI (-1.54, -0.09), and the decrease in lip inclination was MD=-1.61, 95% CI (-2.86, -0.36); these values were significantly different from those before treatment (P<0.05).@*Conclusion@#Invisible orthodontic appliances can effectively move the upper molars in a distal direction and control the vertical position of the molars. When the molars move further away, there is some degree of compression and distal tilt movement, which is beneficial for patients with high angles. The sagittal movement of incisors is beneficial for improving the patient's profile.

Relación entre el piso del seno maxilar y las raíces de las piezas posteriores superiores, mediante tomografía computada / Relationship between maxillary sinus floor and the posterior upper teeth roots, by means of computed tomography

Objetivo: El objetivo de este estudio fue evaluar la frecuencia con que las raíces de premolares y molares superiores se encuentran dentro del seno maxilar. Conocer la relación entre dichas estructuras es importante para planificar los procedimientos endodónticos y quirúrgicos a ser realizados en esa región. Materiales y métodos: Se realizó el análisis cualitativo dinámico de 82 tomografías computadas de haz cónico (CBCT) unilaterales, analizándose 738 raíces correspondientes a premolares y molares de una sola hemiarcada superior. Se utilizó sala con iluminación controlada y la observación fue realizada por un solo examinador. El criterio de inclusión requería que la cortical inferior del seno maxilar debía ser visible para poder establecer la relación. Se utilizaron los tres planos tomográficos de visualización, permitiendo ajustes de brillo y contraste. La escala de clasificación de cada raíz consideró su relación como: dentro o fuera del seno maxilar. Los datos obtenidos fueron sometidos a las pruebas de Chi-cuadrado y Test Exacto de Fisher. Resultados: el primer premolar superior mostró una proyección hacia el interior del seno maxilar significativamente menor que las otras piezas dentarias posteriores (p>0.05), observándose su raíz vestibular sin proyección. La raíz palatina del primer premolar superior mostró la mayor incidencia dentro del seno maxilar, con un 39,02% del total de las raíces analizadas (p<0,05). El segundo molar superior mostró considerable proximidad con el seno maxilar, pero con menor incidencia con relación a la raíz palatina del primer molar. Conclusión: los procedimientos endodónticos o quirúrgicos a realizarse en cercanía al seno maxilar deben considerar siempre la relación raíz/seno, para evitar maniobras que lo invadan. La raíz palatina del primer molar superior mostró la mayor incidencia dentro del seno maxilar, con un 39,02% (AU)

Tratamento cirúrgico para recobrimento radicular em molar superior / Surgical treatment for root coverage in the upper molar tooth ­ a case report

A recessão gengival é uma condição muito comum atualmente, definida como o deslocamento da margem gengival apicalmente à junção cemento/esmalte, com consequente exposição da superfície radicular ao ambiente bucal. Apesar das recessões gengivais afetarem diversos grupos de dentes, poucos trabalhos tentam elucidar qual é o melhor protocolo de tratamento para as recessões gengivais presentes em molares. Visando um protocolo cirúrgico que proporcione uma satisfatória taxa de recobrimento radicular e um melhor resultado estético, o presente relato de caso teve como objetivo apresentar uma técnica cirúrgica alternativa para o tratamento de recessões gengivais em molares superiores. Para tal, um retalho dividido foi confeccionado por meio de incisões relaxantes e deslocado lateralmente, a partir da área doadora, para o elemento dental com a recessão. Após o deslocamento do retalho, o mesmo foi suturado em posição. Seis meses após o procedimento, o paciente estava satisfeito com o resultado final alcançado, demonstrando que esse protocolo pode ser uma alternativa de tratamento aos protocolos existentes para o tratamento de recessões gengivais.

Gingival recession is a condition defined as the apical positioning of the gingival margin in relation to the cemento-enamel junction, resulting in root exposure in the oral environment. Although gingival recession may affect many groups of teeth, there are few studies that attempt to clarify which is the best treatment protocol for gingival recessions localized in molars. In order to evaluate a surgical approach that lead to a satisfactory root coverage rate and a good esthetic outcome, the aim of this case report is to present an alternative surgical technique for the treatment of gingival recession in upper molar teeth. For this, a split-flap was made through vertical incisions and laterally positioned from the donor area to the affected tooth and sutured in position. Six months after the procedure, the patient was satisfied with the final result achieved, showing that this protocol may be an alternative to the existing treatments for the gingival recession.

El metaconulo de los molares superiores humanos / The metaconule in the human upper molars

Este artículo presenta la distribución mundial del rasgo Metaconulo en los primeros molares superiores humanos. Su conocimiento poblacional nos ayuda a tener una visión más completa de la morfología dental humana y nos permite tener un referente geográfico y temporal de este rasgo.

This article shows the world wide distribution of Metaconule trait on first human upper molars. The populational record of this trait can help us to know better the human dental morphology, its geographic and microevolution of this dental trait.