RESUMEN
The extraction of permanent molar teeth was first introduced in 1976 as a substitution for premolar extraction in cases with mild crowding. Since then, a number of studies have investigated the effect of permanent molar extraction on dentofacial harmony. Undertaking the procedure of molar extraction is most commonly recommended in response to factors such as: gross caries, large restorations and root-filled teeth, along with its application in the management of anterior open bite and reduction in crowding in facial regions. It has been indicated, however, that before undertaking the extraction of molar teeth it is important to investigate the potential influence of the procedure on other molars, with particular consideration of their eruption path. This is due to the doubt as to the effect of the exact molar teeth extraction and their consequences. In light of this, This review was undertaken to investigate and compare the effect of first, second and the third molar teeth extraction and their subsequent dentofacial complex changes.
Asunto(s)
Erupción Dental , Extracción Dental , Diente Premolar , Humanos , Diente Molar , Tercer MolarRESUMEN
AIM: The purpose of this study was to determine the possible effects of genetic and environmental factors on dentofacial complex using monozygotic twins. MATERIALS AND METHODS: The study sample was made of 21 pairs of monozygotic twins (14 female pairs and seven male pairs) between 10 and 25 years. Pretreatment lateral cephalo-grams were used which were traced and digitized, and various landmarks to determine the anteroposterior and vertical proportions were marked. Samples were divided into two groups. The correlation between groups was found by calculating Pearson's product moment correlation coefficients. RESULTS: The range of the correlation coefficient was from 0.705 to 0.952. Gonial angle showed the highest correlation coefficient (0.952), while saddle angle showed the lowest correlation coefficient (0.705). CONCLUSION: The growth and development of craniofacial complex is under mutifactorial control. However, genetic influences do tend to play a dominant role. CLINICAL SIGNIFICANCE: By studying identical twins, we can study about the interaction of the environment with the genes and how it affects the growth and development of the body in general and dentofacial complex in particular. By utilizing twin studies, we can identify whether a particular trait, disease, or disorder is influenced more strongly by genetics or by the environment. Success of orthodontic treatment depends on a proper diagnosis of the problem including its etiological factors. Genetic studies let the orthodontists to understand the effects of genetic and environmental factors in the growth and development of dentofacial complex better and allows to prevent or treat malocclusions and skeletal anomalies in better ways.