Skeletal anteroposterior discrepancy and vertical type effects on lower incisor preoperative decompensation and postoperative compensation in skeletal Class III patients

Objective: To determine the initial compensation, preoperative decompensation, and postoperative compensation of the lower incisors according to the skeletal anteroposterior discrepancy and vertical type in skeletal Class III patients. Materials and Methods: The samples consisted of 68 skeletal Class III patients treated with twojaw surgery and orthodontic treatment. Lateral cephalograms were taken before preoperative orthodontic treatment (T0) and before surgery (T1) and after debonding (T2). According to skeletal anteroposterior discrepancy/vertical type (ANB, criteria524u; SN-GoMe, criteria 5 35u) at the T0 stage, the samples were allocated into group 1 (severe anteroposterior discrepancy/hypodivergent vertical type, N 5 17), group 2 (moderate anteroposterior discrepancy/hypodivergent vertical type, N 5 17), group 3 (severe anteroposterior discrepancy/hyperdivergent vertical type, N 5 17), or group 4 (moderate anteroposterior discrepancy/hyperdivergent vertical type, N 5 17). After measurement of variables, one-way analysis of variance with Duncans multiple comparison test, crosstab analysis, and Pearson correlation analysis were performed. Results: At T0, groups 3 and 2 exhibited the most and least compensated lower incisors. In group 2, good preoperative decompensation and considerable postoperative compensation resulted in different values for T0, T1, and T2 (IMPA, T0 , T2 , T1; P , .001). However, group 3 did not show significant changes in IMPA between stages. Therefore, groups 2 and 3 showed different decompensation achievement ratios (P , .05). Group 3 exhibited the worst ratios of decompensation and stability (24% and 6%, respectively, P , .001). Anteroposterior discrepancy/ vertical type (ANB: P , .01 at T0 and T1, P , .001 at T2; SN-GoMe: P , .01, all stages) were strongly correlated with relative percentage ratio of IMPA to norm value. Conclusions: Skeletal anteroposterior discrepancy/vertical type results in differences in the amount and pattern of initial compensation, preoperative decompensation, and postoperative compensation of lower incisors in Class III patients. (Angle Orthod. 2011;81:64–74.

Congenital missing permanent teeth in Korean unilateral cleft lip and alveolus and unilateral cleft lip and palate patients

Objective: To investigate the differences in the congenital missing teeth pattern in terms of tooth type (permanent maxillary lateral incisor [MLI] and maxillary second premolar [MSP]) and sidedness (cleft vs noncleft) between boys and girls in Korean unilateral cleft lip and alveolus (UCLA) and unilateral cleft lip and palate (UCLP) patients. Materials and Methods: This study used the charts, models,. radiographs, and intraoral photographs of 90 UCLA patients and 204 UCLP patients (ages 6 to 13 years). Binomial test, chi-square test, Fisher exact test, maximum likelihood analysis of variance, and the odds ratio were performed. Results: According to the relationship between the congenital missing teeth pattern and the cleft type, the UCLP patients had 2.98 times more missing MLIs and 1.80 times more missing MSPs than did the UCLA patients. The MLI was congenitally missing more in boys than in girls, but the MSP showed the opposite tendency. Boys had a higher frequency of congenital missing MLIs and MSPs on the cleft side than did girls. However, on the noncleft side and both sides, girls had a higher frequency of congenital missing MLIs and MSPs than did boys. Results showed a gender-dominant pattern of congenital missing MLIs and MSPs. Conclusion: These results suggest that gender and cleft type might affect the congenital missing teeth pattern in terms of tooth type and sidedness.

Comparison of longitudinal treatment effects with facemask and chincup therapy followed by fixed orthodontic treatment on Class III malocclusion

Objective: The purpose of this study was to compare the longitudinal treatment effects of facemask with rapid maxillary expansion (FM/RME) and chincup (CC) therapy followed by fixed orthodontic treatment (FOT) in Class III malocclusion (CIII) patients. Methods: The samples consisted of twenty-one CIII patients who had similar skeletal and dental characteristics before FM/RME or CC therapy and good retention results (Class I molar/canine relationship and positive overbite/overjet) after FOT (Group 1, FM/RME, n = 11; Group 2, CC, n = 10). Lateral cephalograms were taken before (T0) and after FM/RME or CC therapy (T1), and after FOT and retention (T2). Skeletal and dental variables were measured. Mann-Whitney U-test and Wilcoxon signed-rank test were used for statistical analysis. Results: During T0-T1, FM/RME therapy induced forward movement of point A, and labioversion of the upper incisors. Both groups showed posterior repositioning of the mandible. FM/RME resulted in increase of the vertical dimension; however, CC caused an increase in articular angle and decrease in gonial angle. During T1-T2, both groups exhibited forward growth of point A. Group 1 showed forward growth and counterclockwise rotation of the mandible and increase of IMPA; however, Group 2, showed increase of ANS-Me/N-Me and decrease of overbite. Conclusions: The key factor for successful FM/RME and CC therapy and good retention results might be a harmonized forward growth of the maxilla that could keep pace with the growth and rotation of the mandible

Congenital missing permanent teeth in Korean unilateral cleft lip and alveolus and unilateral cleft lip and palate patients.

Objective: To investigate the differences in the congenital missing teeth pattern in terms of tooth type (permanent maxillary lateral incisor [MLI] and maxillary second premolar [MSP]) and sidedness (cleft vs noncleft) between boys and girls in Korean unilateral cleft lip and alveolus (UCLA) and unilateral cleft lip and palate (UCLP) patients. Materials and Methods: This study used the charts, models, radiographs, and intraoral photographs of 90 UCLA patients and 204 UCLP patients (ages 6 to 13 years). Binomial test, chisquare test, Fisher exact test, maximum likelihood analysis of variance, and the odds ratio were performed. Results: According to the relationship between the congenital missing teeth pattern and the cleft type, the UCLP patients had 2.98 times more missing MLIs and 1.80 times more missing MSPs than did the UCLA patients. The MLI was congenitally missing more in boys than in girls, but the MSP showed the opposite tendency. Boys had a higher frequency of congenital missing MLIs and MSPs on the cleft side than did girls. However, on the noncleft side and both sides, girls had a higher frequency of congenital missing MLIs and MSPs than did boys. Results showed a genderdominant pattern of congenital missing MLIs and MSPs. Conclusion: These results suggest that gender and cleft type might affect the congenital missing teeth pattern in terms of tooth type and sidedness

En masse retraction and two-step retraction of maxillary anterior teeth in adult class I women - A comparison of anchorage loss

Objective: To compare the amount of anchorage loss of the maxillary posterior teeth and amount of retraction of the maxillary anterior teeth between en masse retraction and two-step retraction of the anterior teeth. Materials and Methods: The sample consisted of 30 female adult patients with Class I malocclusion and lip protrusion who needed maximum posterior anchorage. The sample was subdivided into group 1 (n = 15, mean age = 21.4 years, en masse retraction) and group 2 (n = 15, mean age = 24.6 years, two-step retraction). Lateral cephalograms were taken before (T1) and after treatment (T2). Nine skeletal and 10 anchorage variables were measured, and independent t-test was us ed for statistical analysis. Results: Although the amount of horizontal retraction of the maxillary anterior teeth was not different between the two groups, there was mild labial movement of the root apices of the upper incisors in group 2 at T2. There were no significant differences in the degree of anchorage loss of the maxillary posterior teeth between the two groups. Bodily and mesial movements of the upper molars occurred in both groups. Approximately 4 mm of the retraction of the upper incisal edges resulted from 1 mm of anchorage loss in the upper molars in both groups. Conclusion: No significant differences existed in the degree of anchorage loss of the upper posterior teeth and the amount of retraction of the upper anterior teeth associated with en masse retraction and two-step retraction of the anterior teeth.

부정교합이 성인 여자대학생의 자존감에 미치는 영향

Objective: The purpose of this study was to evaluate the effects of malocclusion on the self-esteem of female university students. Methods: The subjects were composed of 67 female university students who showed Class I molar relation, no missing or supernumerary teeth and has had no orthodontic treatment experience. Each subject was evaluated with Rosenberg`s Self-esteem Scale to measure the level of self-esteem and also evaluated the degree of anterior crowding and lip protrusion through model analysis and cephalometric soft tissue profile analysis. Results: The results showed that a protrusive profile and crowding of upper anterior teeth had significant reducing effects on the level of self-esteem. The protrusion and crowding groups showed no significant differences in self-esteem between groups. Conclusions: Malocclusion had significant negative effects on the self-esteem of female university students. Further research to investigate the negative psychological influence of malocclusion and the education of lay people about this influence is necessary. (Korean J Orthod 2008;38(6):388-396)이 논문은 2007년도 교정학회 대국민홍보 연구비 지원에 의하여 연구되었음.

Change in Grafted Secondary Alveolar Bone in Patients with UCLP and UCLA : A Three-Dimensional Computed Tomography Study

Objective: To evaluate changes in the grafted bone after secondary alveolar bone graft (ABG) with iliac bone using 3-dimensional computed tomography (3D-CT). Materials and Methods: The sample consisted of 10 patients with unilateral cleft lip and palate (UCLP) and 5 patients with unilateral cleft lip and alveolus (UCLA) (mean age 10 years). 3DCT data (Sensation 10, Siemens, Munchen, Germany), which was obtained 1 month before (T0), 3 months after (T1), and 12 months (T2) after ABG, were used to measure the height, labiolingual thickness (LLT), and volume of the grafted bone using V-Works 4.0 program (Cybermed Inc, Seoul, Korea). All of the UCLA patients showed the lingual process in the cleft area at T0, but the UCLP did not. Results: During T1–T2, there was a significant decrease in height of the upper part of the grafted bone; however, volumes of both the upper and lower parts were decreased. Unilateral cleft type and presence of ULI in the cleft area did not affect the change in height and volume of the grafted bone. The resorption amount (RA) was significantly larger in the lower part than in the upper part, while the resorption rate (RR) exhibited an opposite result. In addition, there was significantly more RA in the labial side in UCLA than UCLP (P .05). There was no correlation between the initial cleft width and changes in height, LLT, and volume of the grafted bone. Conclusion: Overpacking and/or excessive condensation of the grafted bone is not necessary in UCLA with the lingual process because of the greater chance of resorption on the labial side of the grafted bone

En masse retraction and two-step retraction of maxillary anterior teeth in adult Class I females: a comparison of anchorage loss.

Objective: To compare the amount of anchorage loss of the maxillary posterior teeth and amount of retraction of the maxillary anterior teeth between en masse retraction and two-step retraction of the anterior teeth. Materials and Methods: The sample consisted of 30 female adult patients with Class I malocclusion and lip protrusion who needed maximum posterior anchorage. The sample was subdivided into group 1 (n = 15, mean age = 21.4 years, en masse retraction) and group 2 (n = 15, mean age = 24.6 years, two-step retraction). Lateral cephalograms were taken before (T1) and after treatment (T2). Nine skeletal and 10 anchorage variables were measured, and independent t-test was used for statistical analysis. Results: Although the amount of horizontal retraction of the maxillary anterior teeth was not different between the two groups, there was mild labial movement of the root apices of the upper incisors in group 2 at T2. There were no significant differences in the degree of anchorage loss of the maxillary posterior teeth between the two groups. Bodily and mesial movements of the upper molars occurred in both groups. Approximately 4 mm of the retraction of the upper incisal edges resulted from 1 mm of anchorage loss in the upper molars in both groups. Conclusion: No significant differences existed in the degree of anchorage loss of the upper posterior teeth and the amount of retraction of the upper anterior teeth associated with en masse retraction and two-step retraction of the anterior teeth

New treatment modality for maxillary hypoplasia in cleft patients Protraction facemask with miniplate anchorage

Objective: To present cleft patients treated with protraction facemask and miniplate anchorage (FM/MP) in order to demonstrate the effects of FM/MP on maxillary hypoplasia. Materials and Methods: The cases consisted of cleft palate only (12 year 1 month old girl, treatment duration = 16 months), unilateral cleft lip and alveolus (12 year 1 month old boy, treatment duration = 24 months), and unilateral cleft lip and palate (7 year 2 month old boy, treatment duration = 13 months). Curvilinear type surgical miniplates (Martin, Tuttlinger, Germany) were placed into the zygomatic buttress areas of the maxilla. After 4 weeks, mobility of the miniplates was checked, and the orthopedic force (500 g per side, 30 degrees downward and forward from the occlusal plane) was applied 12 to 14 hours per day. Results: In all cases, there was significant forward displacement of the point A. Side effects such as labial tipping of the upper incisors, extrusion of the upper molars, clockwise rotations of the mandibular plane, and bite opening, were considered minimal relative to that usually observed with conventional protraction facemask with tooth-borne anchorage. Conclusions: FM/MP can be an effective alternative treatment modality for maxillary hypoplasia with minimal unwanted side effects in cleft patients. (Angle Orthod. 2010;80:783-791.)

Which Hard and Soft Tissue Factors Relate with the Amount of Buccal Corridor Space during Smiling?

Objective: To investigate which hard and soft tissue factors relate with the amount of buccal corridor area (BCA) during posed smiling. Materials and Methods: The samples consisted of 92 adult patients (19 men and 73 women; 56 four first bicuspids extraction and 36 nonextraction treatment cases; mean age = 23.5 years), who were treated only with a fixed appliance and finished with Angle Class I canine and molar relationships. To eliminate the crowding effect on the buccal corridor area, lateral cephalograms, dental casts, and standardized frontal posed smile photographs were obtained at debonding stage and 28 variables were measured. Pearson correlation analysis, multiple linear regression analysis, and independent t-test were used to find variables that were related with buccal corridor area ratio (BCAR). Results: Among the lateral cephalometric and dental cast variables, FMA, lower anterior facial height, upper incisor (U1) exposure, U1 to facial plane, lower incisor (L1) to mandibular plane, L1 to N-B, Sn (subnasale) to soft tissue menton (Me′), Sn to stomodium superius (stms), stms to Me′, and interpremolar width were significantly negatively correlated with BCAR. Occlusal plane inclination and buccal corridor linear ratio did not show any significant correlation with BCAR. Multiple linear regression analysis generated a three-variable model: Sn to Me′, U1 exposure, and sum of tooth material (STM) (R2 = 0.324). There was no significant difference in BCAR between extraction and nonextraction groups. Conclusions: To control the amount of BCA for achieving a better esthetic smile, it is necessary to observe the vertical pattern of the face, amount of upper incisor exposure, and sum of the tooth material