RESUMO
The purpose of this study was to compare dental arch transversal and anteroposterior dimensions in three ethnic groups from Colombia. A digital caliper was used to take 16 transversal and two sagittal measurements, 9 for the upper jaw and 9 for the lower jaw. The sagittal measure determining arch length was drawn from a mesial line traced from first right permanent molar to first left permanent molar, and a perpendicular line from the point of contact between central incisive teeth, both for the upper and lower jaw. The dimensions of upper dental arch in the three ethnic groups showed differences in intercanine distance, as well as between premolar and between molar teeth. The same differences were found for lower dental arches. The populations evaluated show distinctive characteristics in dental arch dimensions, thus the mestizo population had narrow arches while the natives had wide arches.
El propósito de éste estudio fue comparar las dimensiones transversal y anteroposterior del arco dental en tres grupos étnicos de Colombia. Se utilizó un calibrador digital para tomar 16 medidas transversales y dos sagitales, 9 maxilares y 9 mandibulares. La medida sagital para determinar la longitud del arco se elaboró a partir de una línea trazada desde mesial primera molar derecho permanente al primer molar izquierdo permanente, y una línea perpendicular desde el punto de contacto entre los incisivos centrales, tanto para el maxilar y mandíbula. Las dimensiones del arco dental maxilar en los tres grupos étnicos mostraron diferencias en la distancia intercanina, así como entre premolares y molares. Las mismas diferencias se encontraron en la mandíbula. Las poblaciones evaluadas presentan características distintivas en las dimensiones del arco dental, por lo que la población mestiza tuvo arcos estrechos, mientras que los nativos tuvieron arcos anchos.
Assuntos
Humanos , Criança , Adolescente , Etnicidade , Arco Dental/anatomia & histologia , Análise de Variância , Colômbia/etnologiaRESUMO
OBJECTIVE: The aim of this laboratory study is to evaluate the influence of the shape and the length limitation of superelastic nickel-titanium (NiTi) archwires on lower incisors inclination during alignment and leveling. METHODS: Metal teeth mounted on a typodont articulator device were used to simulate a malocclusion of the mandibular arch (-3.5 mm model discrepancy). Three different shapes (Standard, Accuform and Ideal) of superelastic NiTi archwires (Sentalloy, GAC, USA) were tested. Specimens were divided in two groups: Group I, with no limitation of the archwire length; and Group II, with distal limitation. Each group had thirty specimens divided into three subgroups differentiated by the archwire shape. All groups used round wires with diameters of 0.014-in, 0.016-in, 0.018-in and 0.020-in. The recording of all intervals was accomplished using standardized digital photographs with orthogonal norm in relation to median sagittal plane. The buccolingual inclination of the incisor was registered using photographs and software CorelDraw. RESULTS: The results were obtained using ANOVA and Tukey's test at a significant level of 5%. The inclination of the lower incisor increased in both groups and subgroups. The shape of the archwire had statistically significant influence only in Group I - Standard (11.76º), Ideal (5.88º) and Accuform (1.93º). Analyzing the influence of the length limitation, despite the mean incisor tipping in Group II (3.91º) had been smaller than Group I (6.52º), no statistically significant difference was found, except for Standard, 3.89º with limitation and 11.76º without limitation. The greatest incisor tipping occurred with the 0.014-in archwires.