Evaluation Of First Premolar Extractions Promoting Third Molar Eruption By Panoramic Radiographs: A Clinical Study

The development of third molars and their influence on the dental arches has been concerned by dental profession for a long time. In modern population, the impaction rate for third molars is higher than any other tooth. One explanation might be that the inadequate retromolar space. If the remodeling resorption at the anterior aspect of the mandibular ramus is limited, the eruption of the mandibular third molars might be blocked. Similarly the lack of compensatory periosteal apposition at the posterior outline of the maxillary tuberosity could prevent eruption of the maxillary third molar. Even if there is enough eruption space the third molar may be impacted since its angulation is not good and the root is not uprighting.It can be divided into the extraction and nonextraction treatment for Angle Class I malocclusion patients according to severity of crowding and protrusion of profile. The two kinds of treatments may produce different effects on third molar angulation and eruption space and then may affect the eruption of third molars. In this study panoramic radiographs were analyzed for third molar angle and position before and after treatment and to indicate the effects of first premolar extraction on third molar eruption.