Maxillary Protrusion with Severe Overjet Treated by Maxillary Anterior Alveolar Osteotomy.

In addition to affecting oral functions such as temporomandibular joint function, mastication, and speech, malocclusion caused by skeletal maxillary prognathism also entails sociopsychological implications. Surgical orthodontic treatment to improve occlusion and oral function and to correct esthetic disharmony is important to improve patients' quality of life. We report the case of a 32-year-old woman who visited our hospital with a chief complaint of proclined upper front teeth. Clinical examination revealed maxillary overgrowth and severe labial inclination of the maxillary incisors with palatal gingival recession. The incisal protrusion was corrected with a maxillary anterior alveolar osteotomy-a surgical orthodontic method that could improve the overbite without causing excessive lingual inclination, while also minimizing orthodontic movement of the maxillary anterior teeth. This treatment is generally indicated in cases of maxillary prognathism with a relatively stable occlusal relationship in the molar region. As a result of the treatment, the patient's chief complaint improved and a long-term functional occlusion was achieved. This paper outlines the pre- and posttreatment skeletal and occlusal changes.

Development of a new evaluation method for orthodontic forces generated in individual patients.

Numerous experimental studies have examined how much orthodontic force is needed to move teeth more smoothly; however, no reports have examined this clinically in individual, living subjects. We aimed to develop a method for quantifying the force exerted on individual teeth by an orthodontic wire to measure how loads placed on crowded teeth change dynamically over time. Accordingly, we fabricated a series of dental casts of patients undergoing orthodontic treatment (using optical impressions and a three-dimensional printer), fitted these models with nickel-titanium wire, and subjected them to bending load tests. During leveling, nickel-titanium wire is generally considered to exert a weak force due to its low elastic modulus, with a weak orthodontic force applied over a long period of time due to its superelasticity; however, we found that the actual energy exerted by nickel-titanium wire is also largely affected by other factors (e.g., amount of crowding).