- Email: [email protected]
Clinicostatistical investigation of supernumerary teeth in the maxillary anterior region
40
orthodontic waves 72 (2013) 36–41
conditions. The results of adhesive paste comparisons with different consistencies showed that adhesives with lower filler levels produced significantly higher SBS than those with higher levels. No statistically significant differences in SBS were observed under the various bracket-pressing force or pressing-time conditions. Conclusion: Under the described test conditions, when a bracket with a plastic base was bonded using an adhesive paste containing an S-PRG filler, clinically acceptable SBS could be obtained by bonding with a relatively weak force, for a short period. http://dx.doi.org/10.1016/j.odw.2013.01.032
Original article Clinicostatistical investigation of supernumerary teeth in the maxillary anterior region Hidetaka Satake, Tetsuya Yamamoto Department of Oral and Maxillofacial Surgery, Kochi Medical School, Kochi University, Japan Orthod Waves-Jpn Ed 2012; 71(3): 153–158 During the past 29 years, clinicostatistical investigations were performed on 372 cases visiting our department with supernumerary teeth (totaling 491) in the maxillary anterior region.The most frequent patient age was 7 years, and approximately 78 of patients were less than 10 years old. The ratio of male to female was 3.2:1.In approximately 65% of these patients, supernumerary teeth were accidentally found by dental X-ray examinations. The number of supernumerary teeth was 1, 2, and 3, respectively, in 257 cases (69.1%), 111 cases (29.8%), and 4 cases (1.1%).The most frequent location of supernumerary teeth was around the incisors in the maxilla, especially between the right and left upper central incisors, in 290 teeth (59.1%). The direction of eruption was inverted in almost all cases.The presence of diasthema was the most frequent complication (63.3%), followed by displacements of adjacent teeth (13.8%), delayed eruption of permanent teeth (12.7%), formation of dentigerous cysts (9.1%), and ulcer formations (1.1%).Supernumerary teeth were extracted in 95.4% of the patients. These results suggest that it is necessary to examine for the presence of supernumerary teeth in the maxillary anterior region by X-rays when abnormal findings, such as diasthema and displacement of the adjacent teeth, are found in boys who are approximately 7 years old.
http://dx.doi.org/10.1016/j.odw.2013.01.033
Original article Comparison of dental arch form between Japanese and Mongolian subjects with normal occlusion Takashi Tsuchimochi, Kazuhito Arai Department of Orthodontics, School of Life Dentistry at Tokyo, The Nippon Dental University, Japan Orthod Waves-Jpn Ed 2012; 71(3): 159–169 This study aimed to compare the mandibular clinical dental arch form of Mongolian and Japanese subjects with normal occlusion in terms of the mesiodistal width of the teeth, dental
arch width and depth, fitting fourth-order polynomial equation, and subjective classification. Mandibular dental casts of 36 Mongolian subjects (18 males and females, mean age 19.5 1.6) and 39 Japanese subjects (19 males and 20 females, mean age 20.4 1.9) with normal occlusions were selected. Mesiodistal crown widths were measured using a digital caliper. Dental casts were scanned and analyzed by a laser scanning system. Facial axis points were identified on each tooth; the dental arch width and depth at the canine and molar levels were measured; and the dental arch ratios were calculated. Fourthorder polynomial equations were fit to each dental arch. Also, the dental arches were subjectively classified into square, ovoid, and tapered arch forms using a set of templates. The results revealed that premolars and the mandibular second molar were significantly smaller in Mongolian subjects. Mandibular dental arch width for Mongolian subjects was significantly wider at the molars and had shorter depth. Dental arch ratios indicated that the Mongolian subjects also had a wider dental arch at the molars. The mean coefficient of fourth-order terms in the polynomial equation was larger in the Japanese subjects, suggesting a more squared shape. However, no significant difference was observed in the subjective classifications. In conclusion, clinical mandibular dental arch forms for the Mongolian subjects were generally wider at the molars and had shorter depths.
http://dx.doi.org/10.1016/j.odw.2013.01.034
Original article Clinical application of acoustic analysis in evaluation of tongue function Kaori Ishii, Katsuhiko Saitoh, Kazutaka Kasai Department of Orthodontics, Nihon University School of Dentistry at Matsudo, Japan Orthod Waves-Jpn Ed 2012; 71(3): 170–177 The purpose of this study was to make criteria for acoustic analysis and to investigate acoustic characteristics of orthodontic patients. The subjects were 16 female students at the school of dentistry (normal group), 4 women with experiences in voice training (narrator group), 22 patients in need of myofunctional therapy (MFT group), and 11 patients with skeletalclass – malocclusion (surgery group). The frequencies of the first formant (F1), the second formant (F2), and theR fourth formant (F0 4) of the postalveolar fricative consonant / / were analyzed. In the surgery group, a voice recording was carried out before orthognathic surgery (T1), 1 month postoperatively (T2), and 3 months postoperatively (T3). Cephalometric analysis was made at T1 and T2. The results were as follows:
1. No significant differences were found between the normal group and the narrator group. 2. F2/F0 4 in the MFT group was significantly higher than in the normal group. 3. No significant differences were found in F1/F0 4 between the normal group and the surgery group. F2/F0 4 in the latter was significantly higher than in the normal group at T1. But there were no significant differences at T2 and T3. 4. No significant differences were found in the tongue rest position between T1 and T2.
orthodontic waves 72 (2013) 36–41
conditions. The results of adhesive paste comparisons with different consistencies showed that adhesives with lower filler levels produced significantly higher SBS than those with higher levels. No statistically significant differences in SBS were observed under the various bracket-pressing force or pressing-time conditions. Conclusion: Under the described test conditions, when a bracket with a plastic base was bonded using an adhesive paste containing an S-PRG filler, clinically acceptable SBS could be obtained by bonding with a relatively weak force, for a short period. http://dx.doi.org/10.1016/j.odw.2013.01.032
Original article Clinicostatistical investigation of supernumerary teeth in the maxillary anterior region Hidetaka Satake, Tetsuya Yamamoto Department of Oral and Maxillofacial Surgery, Kochi Medical School, Kochi University, Japan Orthod Waves-Jpn Ed 2012; 71(3): 153–158 During the past 29 years, clinicostatistical investigations were performed on 372 cases visiting our department with supernumerary teeth (totaling 491) in the maxillary anterior region.The most frequent patient age was 7 years, and approximately 78 of patients were less than 10 years old. The ratio of male to female was 3.2:1.In approximately 65% of these patients, supernumerary teeth were accidentally found by dental X-ray examinations. The number of supernumerary teeth was 1, 2, and 3, respectively, in 257 cases (69.1%), 111 cases (29.8%), and 4 cases (1.1%).The most frequent location of supernumerary teeth was around the incisors in the maxilla, especially between the right and left upper central incisors, in 290 teeth (59.1%). The direction of eruption was inverted in almost all cases.The presence of diasthema was the most frequent complication (63.3%), followed by displacements of adjacent teeth (13.8%), delayed eruption of permanent teeth (12.7%), formation of dentigerous cysts (9.1%), and ulcer formations (1.1%).Supernumerary teeth were extracted in 95.4% of the patients. These results suggest that it is necessary to examine for the presence of supernumerary teeth in the maxillary anterior region by X-rays when abnormal findings, such as diasthema and displacement of the adjacent teeth, are found in boys who are approximately 7 years old.
http://dx.doi.org/10.1016/j.odw.2013.01.033
Original article Comparison of dental arch form between Japanese and Mongolian subjects with normal occlusion Takashi Tsuchimochi, Kazuhito Arai Department of Orthodontics, School of Life Dentistry at Tokyo, The Nippon Dental University, Japan Orthod Waves-Jpn Ed 2012; 71(3): 159–169 This study aimed to compare the mandibular clinical dental arch form of Mongolian and Japanese subjects with normal occlusion in terms of the mesiodistal width of the teeth, dental
arch width and depth, fitting fourth-order polynomial equation, and subjective classification. Mandibular dental casts of 36 Mongolian subjects (18 males and females, mean age 19.5 1.6) and 39 Japanese subjects (19 males and 20 females, mean age 20.4 1.9) with normal occlusions were selected. Mesiodistal crown widths were measured using a digital caliper. Dental casts were scanned and analyzed by a laser scanning system. Facial axis points were identified on each tooth; the dental arch width and depth at the canine and molar levels were measured; and the dental arch ratios were calculated. Fourthorder polynomial equations were fit to each dental arch. Also, the dental arches were subjectively classified into square, ovoid, and tapered arch forms using a set of templates. The results revealed that premolars and the mandibular second molar were significantly smaller in Mongolian subjects. Mandibular dental arch width for Mongolian subjects was significantly wider at the molars and had shorter depth. Dental arch ratios indicated that the Mongolian subjects also had a wider dental arch at the molars. The mean coefficient of fourth-order terms in the polynomial equation was larger in the Japanese subjects, suggesting a more squared shape. However, no significant difference was observed in the subjective classifications. In conclusion, clinical mandibular dental arch forms for the Mongolian subjects were generally wider at the molars and had shorter depths.
http://dx.doi.org/10.1016/j.odw.2013.01.034
Original article Clinical application of acoustic analysis in evaluation of tongue function Kaori Ishii, Katsuhiko Saitoh, Kazutaka Kasai Department of Orthodontics, Nihon University School of Dentistry at Matsudo, Japan Orthod Waves-Jpn Ed 2012; 71(3): 170–177 The purpose of this study was to make criteria for acoustic analysis and to investigate acoustic characteristics of orthodontic patients. The subjects were 16 female students at the school of dentistry (normal group), 4 women with experiences in voice training (narrator group), 22 patients in need of myofunctional therapy (MFT group), and 11 patients with skeletalclass – malocclusion (surgery group). The frequencies of the first formant (F1), the second formant (F2), and theR fourth formant (F0 4) of the postalveolar fricative consonant / / were analyzed. In the surgery group, a voice recording was carried out before orthognathic surgery (T1), 1 month postoperatively (T2), and 3 months postoperatively (T3). Cephalometric analysis was made at T1 and T2. The results were as follows:
1. No significant differences were found between the normal group and the narrator group. 2. F2/F0 4 in the MFT group was significantly higher than in the normal group. 3. No significant differences were found in F1/F0 4 between the normal group and the surgery group. F2/F0 4 in the latter was significantly higher than in the normal group at T1. But there were no significant differences at T2 and T3. 4. No significant differences were found in the tongue rest position between T1 and T2.