Effect of orthodontic treatment involving first premolar extractions on mandibular third molar angulation and retromolar space

Abstract

BackgroundThird molars present more problems than other teeth because they are the last teeth to erupt, and so it is important to assess their development when designing an orthodontic treatment plan. The aim of this study was to compare the angulation of the mandibular third molar and retromolar space before and after orthodontic treatment in cases involving first premolar extraction.Material and Methods76 patients, 59 women (77.63%) and 17 men (22.36%), were recruited from the Orthodontics Clinic at Benemérita Universidad Autónoma de Puebla (Mexico). Panoramic radiographs were analyzed before and after orthodontic treatment that included first premolar extractions, measuring retromolar space (RS) and the angles formed by the intersection of the axes of the third and second molar (α) and the intersection of the axis of the mandibular plane and third molar (β).ResultsThe data obtained underwent statistical analysis. The angle α and β showed statistically significant differences on the left side in women. In men, only the right side α angle showed significant differences. Retromolar space increased significantly on both sides for both sexes.ConclusionsThird molar angulation presents different behaviors between men and women, with greater verticalization in women. Key words:Third molar, retromolar space, orthodontics.

Beyond the ARCH: Examining mandibular third molar movements in response to premolar and single incisor extractions in orthodontic practice

“…20 In contrary to the above studies significant relationship was observed between the initial age of the patient and the amount of change in the inclination of the third molar in a study by Schiller et.al. 21 There is gender-specific variations in the angulation of third molars, demonstrating a higher degree of verticalization in women compared to men 22 As with previous M3 studies, the present study did not reveal a basis to predict the eruption of M3. 23 In a study conducted by Al kuwari etal it was concluded that the orthodontic treatment involving first premolar extraction has shown improvement in the angulation of third molars during eruption, thereby supporting the implementation of orthodontic extraction therapy in borderline cases.…”

Improvement of the Impacted Level of Lower Third Molars After Orthodontic Treatment

“…The majority of previous findings reported that premolar extraction did not affect M3–M2. 14 , 17 , 18 , 19 , 20 , 35 , 36 Although the mandibles can keep growing until age 25, their growth rate substantially reduces in the postpubertal period, and the bone almost reaches its maximum size at approximately 18 years. 37 A longitudinal study reported that unerupted M3 generally remained in an impacted condition, and the angulation slowly increased by approximately 20° after 12 years of follow-up.…”

“… 14 , 15 , 16 However, the results were controversial because of the variety of demographic characteristics (eg, age, sex), evaluation methods, biomechanics of the orthodontic treatment, and characteristics of the PE group. Most previous studies reported that premolar extraction did not affect M3 angulation measured by either M3–M2 angle 17 , 18 , 19 , 20 or M3–occlusal plane (M3–OP) angle. 17 , 19 Contrarily, M3–M2 angle, 21 M3–horizontal plane (M3–HP), 22 and M3 eruption space 17 , 19 , 23 were found to improve in studies with carefully selected orthodontic cases.…”

“…Most previous studies reported that premolar extraction did not affect M3 angulation measured by either M3–M2 angle 17 , 18 , 19 , 20 or M3–occlusal plane (M3–OP) angle. 17 , 19 Contrarily, M3–M2 angle, 21 M3–horizontal plane (M3–HP), 22 and M3 eruption space 17 , 19 , 23 were found to improve in studies with carefully selected orthodontic cases. More importantly, M3 impaction was not fully assessed in 3 perspectives: eruption space, obstruction, and position in most of previous studies.…”

Pain Sensation: Infrequent Case of Root Resorption of the Lower Second Molar Root with Bone Regeneration after Impacted Third Molar Removal

“…This impacted condition may cause several pathological conditions including carious lesions in the adjacent tooth, pericoronitis, periodontal conditions, odontogenic or dentigerous cysts, and tumors and external root resorption (ERR) of second molars. [1][2][3] ERR of lower second molars, considered as pressure resorption, is a pathological process caused by LITM, the action of orthodontic appliances, chronic periapical periodontitis, dental trauma, cysts, and tumors. The incidence of ERR in lower second molars caused by LITM is not prevalent as cited in several previous studies 4 wherein its incidence varies from 3.05% to 24.2%.…”