Maxillary first molar extraction in Class II malocclusion: Follow-up studies on treatment effects

This PhD research investigated treatment effects of extraction of one and two maxillary first molars in Class II subdivision and Class II/1 malocclusion cases respectively from a longer time perspective. Private practice records were scrutinized to evaluate aspects of a treatment technique combining maxillary first molar extraction(s) and Begg brackets; outcome stability, influence on the position of maxillary third molars, interference of adjacent anatomical structures in closing extraction spaces, and effectiveness of fixed retainers in preventing vertical movement of mandibular second molars without contacts with maxillary teeth. Based on our results, extraction of a maxillary first molar and orthodontics led to favourable and stable results regarding aesthetics and occlusion. In patients treated with one and two extractions, the position of maxillary third molars improved by 3 to 4 times more compared to nonextraction maxillary halves and subjects. When applying this technique, clinicians should be aware of the possible interference of a large maxillary sinus in achieving upright position of maxillary second molars, and the capacity of retention wires to inhibit displacement of mandibular posterior teeth lacking occlusal contacts. Overall, there is evidence that maxillary first molar extraction(s) followed by orthodontic treatment, when carried out properly, and in selected cases, may be rewarding in clinical terms, and therefore may be preferred instead of extraction of premolars.