Three-dimensional evaluation of dentofacial transverse widths of adults with various vertical facial patterns

Hwang, Soonshin,Jeong, Seokjin,Choi, Yoon Jeong,Chung, Chooryung J.,Lee, Hye Sun,Kim, Kyung-Ho Elsevier 2018 American journal of orthodontics and dentofacial o Vol.153 No.5

<P><B>Introduction</B></P> <P>The purpose of this study was to investigate maxillomandibular transverse widths and molar inclinations of adults with hypodivergent, normodivergent, and hyperdivergent facial patterns using cone-beam computed tomography.</P> <P><B>Methods</B></P> <P>We evaluated Class I subjects (55 men, 66 women) who were divided into hypodivergent (<27°), normodivergent (28°-37°), and hyperdivergent (>38°) groups by their mandibular plane angles. Frontal and coronal views of the images were analyzed. Sex differences, vertical facial pattern differences, and related factors were assessed with independent 2-sample <I>t</I> tests, 1-way analysis of variance followed by post hoc Tukey tests, and Pearson correlation analysis.</P> <P><B>Results</B></P> <P>The hypodivergent group had greater maxillary alveolar widths 7 mm apically from the alveolar crest. The intermolar widths and molar inclinations showed no significant differences among the groups. As the mandibular plane angles increased, interjugular widths, transverse mandibular widths, and buccolingual maxillary alveolar widths at the midroot level decreased, whereas the maxillomandibular width differences and palatal heights increased im both sexes.</P> <P><B>Conclusions</B></P> <P>An increase in the mandibular plane angle is associated with tendencies of narrow mandibular arches, thinner maxillary alveolar bones at the midroot level, and higher palatal arches in both sexes. Intermolar widths and molar inclinations were not significantly affected by vertical facial patterns.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Maxillomandibular transverse width and molar inclinations were assessed in adults. </LI> <LI> Subjects were grouped by hypodivergent, normodivergent, and hyperdivergent facial pattern. </LI> <LI> Intermolar widths and molar inclinations were not significantly affected by facial pattern. </LI> <LI> Increased mandibular plane angle was associated with narrow mandibular arches. </LI> <LI> It was also associated with thinner maxillary alveolar bones midroot and high palatal arches. </LI> </UL> </P>

Posterior dental compensation and occlusal function in adults with different sagittal skeletal malocclusions

Soonshin Hwang,최윤정,Sooin Jung,Sujin Kim,정주령,김경호 대한치과교정학회 2020 대한치과교정학회지 Vol.50 No.2

Objective: The aim of this study was to compare posterior tooth inclinations, occlusal force, and contact area of adults with different sagittal malocclusions. Methods: Transverse skeletal parameters and posterior tooth inclinations were evaluated using cone beam computed tomography images, and occlusal force as well as contact area were assessed using pressure-sensitive films in 124 normodivergent adults. A linear mixed model was used to cluster posterior teeth into maxillary premolar, maxillary molar, mandibular premolar, and mandibular molar groups. Differences among Class I, II, and III groups were compared using an analysis of variance test and least significant difference post-hoc test. Correlations of posterior dental inclinations to occlusal function were analyzed using Pearson’s correlation analysis. Results: In male subjects, maxillary premolars and molars had the smallest inclinations in the Class II group while maxillary molars had the greatest inclinations in the Class III group. In female subjects, maxillary molars had the smallest inclinations in the Class II group, while maxillary premolars and molars had the greatest inclinations in the Class III group. Occlusal force and contact area were not significantly different among Class I, II, and III groups. Conclusions: Premolar and molar inclinations showed compensatory inclinations to overcome anteroposterior skeletal discrepancy in the Class II and III groups; however, their occlusal force and contact area were similar to those of Class I group. In subjects with normodivergent facial patterns, although posterior tooth inclinations may vary, difference in occlusal function may be clinically insignificant in adults with Class I, II, and III malocclusions. [Korean J Orthod 2020;50(2):98-107]

Long-term survival of retained deciduous mandibular second molars and maxillary canine incorporated into final occlusion

Soonshin Hwang,Yoon Jeong Choi,Chooryung J. Chung,Kyung-Ho Kim 대한치과교정학회 2017 대한치과교정학회지 Vol.47 No.5

Orthodontic treatment of a complex case that involves retained deciduous mandibular second molars with missing permanent successors is challenging. Usually, congenitally missing teeth are manifested with other dental anomalies that further complicate orthodontic treatment, such as retained deciduous teeth, impactions, transpositions and peg-shaped lateral incisors. Even though the long term prognosis of the retained deciduous tooth is not fully predictable, if the teeth are in good condition, the patient and clinician may incline towards a decision to preserve the deciduous teeth as long as possible. This case report demonstrates that deciduous teeth, in this case the mandibular second molars and maxillary canine, can be incorporated into final occlusion with clinically stable long-term results.

Orthodontic Traction of the Impacted Mandibular Third Molars to Replace Severely Resorbed Mandibular Second Molars

Hwang, Soonshin,Choi, Yoon Jeong Korean Academy of Dental Science 2016 Journal of korean dental science Vol.9 No.1

Prophylactic removal of impacted third molars is a common procedure in dentistry, but the necessity of routine extraction is still controversial. When impacted third molars caused severe apical root resorption of the second molars, orthodontic traction of the third molars after extraction of the damaged second molars could minimize alveolar bone defect and preserve the patient's natural teeth. By well-planned orthodontic treatment, functional occlusion was established avoiding extraction of the impacted teeth and eliminating the possibility of a large bone defect after extraction.

The effect of cetirizine, a histamine 1 receptor antagonist, on bone remodeling after calvarial suture expansion

Soonshin Hwang,Chooryung J. Chung,Yoon Jeong Choi,Taeyeon Kim,김경호 대한치과교정학회 2020 대한치과교정학회지 Vol.50 No.1

Objective: The objective of this study was to evaluate the effects of cetirizine, a histamine 1 receptor antagonist, on bone remodeling after calvarial suture expansion. Methods: Sixty male Sprague–Dawley rats were divided into 4 groups; the phosphate-buffered saline (PBS)-injected no expansion group, cetirizine-injected no expansion group, PBS-injected expansion group, and cetirizine-injected expansion group, and were observed at 7, 14, and 28 days. Five rats per group were examined at each observation day. Daily injections of cetirizine or PBS were administered to the relevant groups starting 2 weeks prior to expander insertion. A rapid expander was inserted in the calvarial bone to deliver 100 cN of force to the parietal suture. The specimens were prepared for hematoxylin and eosin and tartrate-resistant acid phosphatase (TRAP) staining. Suture opening and bone regeneration were evaluated using microcomputed tomography and bone histomorphometric analysis. Serum blood levels of osteocalcin and carboxy-terminal collagen crosslinks (CTX) were also evaluated. Results: TRAP-positive cell counts and CTX levels decreased while osteocalcin levels increased in the cetirizine-injected expansion group at observation day 28. In the expansion groups, the mineralized area gradually increased throughout the observation period. At day 28, the cetirizine-injected expansion group showed greater bone volume density, greater mineralized area, and narrower average suture width than did the PBS-injected expansion group. Conclusions: Cetirizine injection facilitated bone formation after suture expansion, mostly by suppressing osteoclastic activity. Histamine 1 receptor antagonists may aid in bone formation after calvarial suture expansion in the rat model.

Orthodontic Traction of the Impacted Mandibular Third Molars to Replace Severely Resorbed Mandibular Second Molars

Soonshin Hwang,Yoon Jeong Choi 대한치의학회 2016 Journal of korean dental science Vol.9 No.1

Three-dimensional evaluation of dentofacial transverse widths in adults with different sagittal facial patterns

Hwang, Soonshin,Song, Jueon,Lee, Joongoo,Choi, Yoon Jeong,Chung, Chooryung J.,Kim, Kyung-Ho Elsevier 2018 American journal of orthodontics and dentofacial o Vol.154 No.3

<P><B>Introduction</B></P> <P>The aim of this study was to evaluate the dentofacial transverse dimensions of subjects with different sagittal facial patterns using 3-dimensional cone-beam computed tomography images.</P> <P><B>Methods</B></P> <P>Cone-beam computed tomography images of 63 men and 80 women were divided into skeletal Class I, Class II, and Class III groups. Skeletal and dental evaluations were made on frontal views and coronal cross-sections of the images. Independent 2-sample <I>t</I> tests and 1-way analysis of variance followed by post hoc Tukey tests were used for sex and group differences. Pearson correlation analysis was used to identify factors related to changes in ANB angle.</P> <P><B>Results</B></P> <P>The Class II subjects did not show differences in maxillomandibular width and maxillary width compared with Class I subjects; however, their maxillary molars were more lingually tipped. The Class III subjects showed greater maxillomandibular width differences and smaller maxillary widths and maxillary buccolingual alveolar widths at midroot level compared with Class I subjects. The maxillary molars were buccally inclined, and the mandibular molars were lingually compensated in Class III subjects. The ANB angle showed positive correlations with jugal process width, maxillary width, and maxillary buccolingual alveolar width at midroot level as well as mandibular molar buccal inclination; negative correlations were found in maxillomandibular width difference, mandibular width at midroot level, and maxillary molar buccal inclination.</P> <P><B>Conclusions</B></P> <P>A relative comparison of Class I, Class II, and Class III subjects showed that dental compensation had occurred to overcome the transverse skeletal discrepancies in the maxillary posterior segments of Class II and Class III subjects. This could escalate unidentified periodontal and functional problems in the long term. Future studies of transverse dentofacial dimensions, including periodontal evaluations and occlusal forces, would be useful for delivering proper orthodontic treatment for skeletal Class II and Class III subjects.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Maxillomandibular transverse width and molar inclination were evaluated on CBCT images. </LI> <LI> Subjects were adults with Class I, II, or III skeletal relationship. </LI> <LI> Dental compensation overcame maxillary posterior transverse discrepancy in Class II and III adults. </LI> <LI> This could escalate unidentified periodontal and functional problems in the long term. </LI> </UL> </P>

Assessment of lower incisor alveolar bone width using cone-beam computed tomography images in skeletal Class III adults of different vertical patterns

Sanghee Lee,Soonshin Hwang,Woowon Jang,Yoon Jeong Choi,Chooryung J Chung,Kyung-Ho Kim 대한치과교정학회 2018 대한치과교정학회지 Vol.48 No.6

Objective: This study was performed to investigate the alveolar bone of lower incisors in skeletal Class III adults of different vertical facial patterns and to compare it with that of Class I adults using cone-beam computed tomography (CBCT) images. Methods: CBCT images of 90 skeletal Class III and 29 Class I patients were evaluated. Class III subjects were divided by mandibular plane angle: high (SN-MP 〉 38.0°), normal (30.0° 〈 SN-MP 〈 37.0°), and low (SN- MP 〈 28.0°) groups. Buccolingual alveolar bone thickness was measured using CBCT images of mandibular incisors at alveolar crest and 3, 6, and 9 mm apical levels. Linear mixed model, Bonferroni post-hoc test, and Pearson correlation analysis were used for statistical significance. Results: Buccolingual alveolar bone in Class III high, normal and low angle subjects was not significantly different at alveolar crest and 3 mm apical level while lingual bone was thicker at 6 and 9 mm apical levels than on buccal side. Class III high angle group had thinner alveolar bone at all levels except at buccal alveolar crest and 9 mm apical level on lingual side compared to the Class I group. Class III high angle group showed thinner alveolar bone than the Class III normal or low angle groups in most regions. Mandibular plane angle showed negative correlations with mandibular anterior alveolar bone thickness. Conclusions: Skeletal Class III subjects with high mandibular plane angles showed thinner mandibular alveolar bone in most areas compared to normal or low angle subjects. Mandibular plane angle was negatively correlated with buccolingual alveolar bone thickness.

Treatment satisfaction and its influencing factors among adult orthodontic patients

Lee, Rami,Hwang, Soonshin,Lim, Hyunsun,Cha, Jung-Yul,Kim, Kyung-Ho,Chung, Chooryung J. Elsevier 2018 American journal of orthodontics and dentofacial o Vol.153 No.6

<P><B>Introduction</B></P> <P>The aim of this study was to investigate the level of satisfaction for orthodontic treatment among adult patients. In addition, the influencing host factors were monitored for their associations with satisfaction.</P> <P><B>Methods</B></P> <P>A questionnaire was designed to measure the level of satisfaction in 10 items; overall satisfaction, tooth alignment, facial appearance, eating and chewing, confident smile and self-image, retention state, treatment duration, treatment costs, intention to recommend, and relief of previous concerns, using a 5-point Likert scale. Total satisfaction was calculated by averaging the Likert scores from the 10 items. The survey was conducted, and the results from 298 adults were evaluated.</P> <P><B>Results</B></P> <P>For the overall satisfaction item, 45.0% were very satisfied, and 39.9% were satisfied, resulting in a satisfaction ratio of 84.9%. Total satisfaction score was 3.9. The level of satisfaction for tooth alignment and confident smile and self-image were significantly higher than facial appearance and eating and chewing (<I>P</I> <0.001). Patients aged 50 and above were more satisfied than the younger ones, and men were more satisfied than women (<I>P</I> <0.05).</P> <P><B>Conclusions</B></P> <P>Overall, adult patients were highly satisfied with orthodontic treatment. Age, sex, motivation, expected concern, and discomfort influenced the level of satisfaction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A questionnaire was developed to measure treatment satisfaction among adults. </LI> <LI> In general, adult patients were highly satisfied with orthodontic treatment. </LI> <LI> Adults age 50 and above were more satisfied than younger age groups. </LI> <LI> Sex, motivation, concerns, and discomfort influenced the level of satisfaction. </LI> </UL> </P>

Periodontal and root changes after orthodontic treatment in middle-aged adults are similar to those in young adults

Han, Jihee,Hwang, Soonshin,Nguyen, Tung,Proffit, William R.,Soma, Kunimichi,Choi, Yoon Jeong,Kim, Kyung-Ho,Chung, Chooryung J. Elsevier 2019 American journal of orthodontics and dentofacial o Vol.155 No.5

<P><B>Introduction</B></P> <P>The goal of this study was to compare the outcomes and amount of change in periodontal health of anterior teeth in young versus middle-aged adults, who were treated to improve anterior alignment and occlusion.</P> <P><B>Methods</B></P> <P>Pre- and posttreatment records including orthodontic casts, cephalograms, and standardized periapical radiographs were retrospectively collected from young adults (aged 19-30 years; n = 12) and middle-aged adults (aged ≥40 years; n = 27). Following the American Board of Orthodontics criteria, discrepancy index (DI), cast-radiograph evaluation (CRE), treatment duration (TD), marginal bone loss (MBL), and tooth length (TL) were measured, and with the use of periapical radiographs, changes in the level of marginal bone (MBC) and the amount of root resorption (RR) after orthodontic treatment were calculated.</P> <P><B>Results</B></P> <P>DI, MBL, and TD were significantly higher in the middle-aged adults than in the young adults (<I>P</I> < 0.05). However, CRE and MBC after treatment were similar between the 2 groups (<I>P</I> > 0.05). The mean amount of RR following treatment was −0.6 ± 0.44 mm and −1.0 ± 0.61 mm in young and middle-aged adults, respectively. The degree of RR after compensating for treatment complexity and TD was similar between the 2 groups (<I>P</I> > 0.05).</P> <P><B>Conclusions</B></P> <P>Although the initial malocclusion and periodontal conditions were unfavorable for the middle-aged adults, the overall treatment and periodontal outcomes after orthodontic treatment of the anterior teeth were similar to those for young adults. It appears that older adults tolerate orthodontics to improve the appearance of the anterior teeth as well as younger adults, with no additional burden because of their increased age.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Treatment outcomes in the anterior teeth were evaluated in young and middle-aged adults. </LI> <LI> Marginal bone loss and root resorption were measured with the use of standardized periapical radiographs. </LI> <LI> Occlusal changes were monitored with the use of modified discrepancy index and cast-radiograph evaluation. </LI> <LI> The magnitude of periodontal and root changes after treatment in middle-aged adults was similar to that in young adults, although the cumulative change was greater in the older group. </LI> </UL> </P>