Affiliation:
1. Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
Abstract
Background: We investigated treatment outcomes and post-treatment stability in 10 patients with an anterior open bite and nonsurgical orthodontics. Methods: The patients underwent maxillary molar intrusion using temporary anchorage devices (TADs) to deepen the overbite due to mandibular autorotation. Lateral cephalograms and dental cast models were obtained before treatment (T0), immediately after it (T1), and >1 year after it (T2). Skeletal and dental cephalometric changes and three-dimensional movements of the maxillary dentitions were evaluated. Results: At T0, cephalometric analysis indicated that patients had skeletal class I with tendencies for a class II jaw relationship and a skeletal open bite. During active treatment (T0 to T1), the maxillary first molar intruded by 1.6 mm, the mandibular first molar extruded by 0.3 mm, the Frankfort-mandibular plane angle decreased by 1.1°, and the overbite increased by 4.1 mm. Statistically significant changes were observed in the amount of vertical movement of the maxillary first molar, Frankfort-mandibular plane angle, and overbite. Three-dimensional (3D) dental cast analysis revealed that the maxillary first and second molars intruded, whereas the anterior teeth extruded, with the second premolar as an infection point. In addition, the maxillary molar was tipped distally by 2.9° and rotated distally by 0.91°. Statistically significant changes were observed in the amount of vertical movement of the central incisor, lateral incisor, canine and first molar, and molar angulation. From T1 to T2, no significant changes in cephalometric measurements or the 3D position of the maxillary dentition were observed. The maxillary and mandibular dentitions did not significantly change during post-treatment follow-up. Conclusions: Maxillary molar intrusion using mini-screws is an effective treatment for open bite correction, with the achieved occlusion demonstrating 3D stability at least 1 year after treatment.
Reference38 articles.
1. Open-Bite: Diagnosis and Treatment;Subtelny;Am. J. Orthod.,1964
2. Ministry of Health, Labour and Welfare (2024, March 20). Distribution of Occlusal Status (Over-Bite) in the Permanent Dentition, by Sex and Age Group (12 to 20 Years of Age). In The Survey of Dental Diseases (2011); 2023. Available online: https://www.mhlw.go.jp/toukei/list/dl/62-17c23-1.pdf.
3. Nonsurgical Management of the Anterior Open Bite: A Review of the Options;Beane;Semin. Orthod.,1999
4. Dummy-and Finger-sucking Habits with Special Attention to Their Significance for Facial Growth and Occlusion. 7. The Effect of Earlier Dummy-and Finger-Sucking Habit in 16-Year-Old Children Compared with Children without Earlier Sucking Habit;Larsson;Swed. Dent. J.,1978
5. Classification of Skeletal Facial Types;Sassouni;Am. J. Orthod.,1969