Nonextraction Class Research Articles

Stability of Class II malocclusion treatment with Class II elastics

The objective of this study was to compare the long-term cephalometric stability after successful therapy of nonextraction Class II malocclusion with elastics and with headgear. The sample comprised 43 patients with Class II malocclusion and was divided into 2 groups. The elastic group (EG) consisted of 20 patients treated with fixed appliances associated with Class II elastics, and the headgear group (HG) consisted of 23 patients treated with fixed appliances and extraoral headgear. Pretreatment, posttreatment, and long-term posttreatment lateral radiographs were evaluated; t tests were used to compare the long-term posttreatment changes between the groups. The groups were matched regarding initial age, time of long-term posttreatment evaluation, initial malocclusion severity, quality of treatment result, and all pretreatment cephalometric variables. Intergroup comparisons of long-term posttreatment changes showed that the HG group presented significantly greater mandibular protrusion, occlusal plane angle decrease, and maxillary molar mesialization. However, long-term posttreatment stability was similar in overjet, overbite, and molar relationships. Nonextraction Class II malocclusion treatment with elastics or extraoral headgear have similar long-term posttreatment stability.

Buccal corridor changes in orthodontically treated extraction and non-extraction Class 1 patients

Patients seek orthodontic treatment mainly to improve their facial aesthetics and obtain an acceptable smile. It is purported that orthodontic extraction treatment may result in narrow buccal corridors which in turn may lead to unaesthetic smile. To determine if the dimensions of the buccal corridors are influenced by extraction or non-extraction treatment in Class 1 patients. Retrospective record-based study conducted between 2012 and 2017 at University of Pretoria Orthodontic department. Smile pictures of pre- and post-treatment Class 1 patients treated with or without premolar extractions were matched. Buccal corridors between the two groups were measured by measurement of visible maxillary dentition and oral aperture dimensions. Data analysis included frequencies and correlations using chi-square test, with a significance level set at p<0.05. Seventy-one patient records met the selection criteria with the majority being females (70%). The age range was between 10 and 37 with a mean of 17.5 years. Thirty-five patients were treated with extractions and thirty-six patients with non-extraction treatment. There was a significant difference in the visible maxillary dentition pre and post treatment with extraction patients showing a 6 to 6 and non-extraction showing 5 to 5 dentition post treatment (p<0.05). There were no differences in the ratios of the visible maxillary dentition and oral aperture in both groups pre and post treatment (p> 0.05). Orthodontic treatment of Class 1 cases with premolar extraction did not lead to deleterious changes in the buccal corridors.

Comparison of efficacy between MBT preadjusted edgewise appliance and clear aligner therapy among class I crowding cases: A randomized controlled trial

BackgroundTo compare the efficacy of McLaughlin Bennett Trevisi (MBT) appliance and Clear Aligner Therapy (CAT) among nonextraction Class I crowding cases. MethodsThe study sample (60 patients) was allotted into two equal groups (30 patients each) using block randomization wherein Group 1: treated with 0.018” MBT appliance and Group 2: treated with CAT for correction of malocclusion. At the end of treatment (T1), treatment duration, chairside time, laboratory time, number, and type of appointments were noted from treatment record cards. For comparing the acceptability among patients treated with both modalities at T1, the patients were interviewed regarding the comfort and ease of using an appliance with a questionnaire-based survey. ResultsThe median number of nonscheduled/emergency and finishing stage appointments was significantly higher in Group 1 compared to Group 2 (P-value <0.001). The median duration of treatment at the scheduled, finishing, and overall appointments, was significantly higher in Group 1 compared to Group 2 (P-value <0.001). The median chairside time of all appointments was significantly higher in Group 1 compared to Group 2 (P-value <0.001). The experience with treatment and overall acceptability was significantly higher in Group 2 compared to Group 1 (P-value <0.001). However, mean laboratory time per aligner fabrication in Group 2 was 30.26 ± 3.45 min against no laboratory time consumed in Group 1. ConclusionsCAT significantly reduces treatment duration, chairside time, number of nonscheduled/emergency, and finishing stage appointments in nonextraction Class I crowding cases. Prospective studies with 3D aligner systems are recommended to add further evidence in this regard. Clinical Trials Registry-India Registration NoCTRI/2018/04/013301.

Esthetic perception of facial profile changes after extraction and nonextraction Class II treatment

This retrospective study evaluated facial profile pleasantness determined by two protocols of Class II treatment. The sample comprised facial profile silhouettes obtained retrospectively from the pretreatment (T1) and posttreatment (T2) cephalograms of 60 patients (42 males and 18 females) divided into two groups. One group of 30 patients (mean age of 12.84 years) was treated with the extraction of maxillary first premolars (mean treatment time of 2.7 years), and the other group of 30 patients (mean age of 12.81 years) was treated with a mandibular advancement appliance (Forsus) (mean treatment time of 2.49 years). The facial profile silhouettes (T1 and T2) were randomly distributed in an album containing one patient per sheet. The examiners consisted of 60 orthodontists and 60 lay individuals, who analyzed the profiles in regard to facial pleasantness, using the Likert scale. A comparison between stages T1 and T2 of the two treatment protocols and between the examiners was performed by mixed-design analysis of variance at a significance level of 5%. The results demonstrated a significant difference between T1 and T2 (greater scores for T2 compared to T1), and between lay individuals and orthodontists (orthodontists assigned higher scores), but with no significant difference between the treatment protocols. Both protocols produced positive effects on the facial profile esthetics, from the standpoint of lay individuals and orthodontists.

The effects of different bracket types on orthodontic treatment evaluated with the objective grading system

Background: Standard edgewise and preadjusted Roth are two bracket types widely used for orthodontic treatment. Whether one of these bracket types offers better treatment results than the other requires further evaluation. The Objective Grading System created by the American Board of Orthodontics (ABO) is one of the most reliable indices used to evaluate treatment outcomes. Objectives: To determine the effects of using two different bracket types on treatment outcomes by using the Objective Grading System. Methods: The sample for this study consisted of 64 randomly selected post-treatment dental casts and panoramic radiographs. Of these samples, 32 were treated with a standard edgewise bracket, and the others were treated with a preadjusted Roth bracket. Patient samples were included if they had non-extraction Class I malocclusion (minor crowding 0.05). The highest score was found for the buccolingual inclination parameter, and the lowest score was for interproximal contacts. Conclusion: According to the Objective Grading System, there are no statistically significant differences between the orthodontic treatment outcomes obtained using a standard edgewise or a preadjusted Roth bracket.

A geometric morphometric evaluation of hard and soft tissue profile changes in borderline extraction versus non-extraction patients.

To evaluate the hard tissue and facial profile changes in matched extraction and non-extraction Class I patients by the use of geometric morphometrics. From a parent sample of 542 Class I patients, previously subjected to discriminant analysis, a subsample of 68 borderline cases was obtained, 34 treated with extraction and 34 without extraction of 4 first premolars. Geometric morphometric methods (Procrustes superimposition and Principal Component Analysis) were applied on cephalometric tracings to assess the validity of the discriminant analysis in successfully identifying a morphologically homogeneous group and to evaluate inter- and intra-group skeletal and facial profile shape changes. No significant pre-treatment shape difference between the two groups was found, thus validating the discriminant analysis. The non-extraction group showed increase in hard tissue facial height (P < 0.001), with slight lower lip retrusion and upper lip protrusion (P = 0.027). The extraction group showed retraction of the hard tissue and facial profile outline (P < 0.001). Permutation tests for post-treatment inter-group differences resulted in P = 0.054 for the soft tissue outline and P = 0.078 for the hard tissue skeletal component. The evidence indicates that borderline cases treated with four premolar extractions will exhibit lip retrusion compared to non-extraction treatment.

Correlation in changes in the upper and lower incisor inclinations toward the nasolabial angle and mentolabial angle in non-extraction Class I malocclusion orthodontic treatment

Non-extraction orthodontic treatment in borderline cases is reported, according to some authors, to lead to upper and lower incisor inclination changes affecting patients’ soft tissue profiles. Here, we aim to determine the correlation, in non-extraction Class I malocclusion cases, between the upper and lower incisor inclination changes toward the nasolabial angle and the mentolabial angle before and after orthodontic treatment. (We took before and after lateral cephalometric radiographs on 26 patients with non-extraction Class I malocclusion orthodontic treatment.) We measured the I-SN, IMP, nasolabial, and mentolabial angles. For statistical analysis, we used the non-parametric Wilcoxon test and the Spearmen correlation test. There was no significant difference between the I-SN and nasolabial angles, but a significant difference between the IMP and mentolabial angles, before and after treatment. The correlation test showed very weak negative and positive correlations between the change in the I-SN angle and the change in the nasolabial angle, and the change in the IMP angle and the change in the mentolabial angle, respectively. The decrease in the I-SN angle was followed by an increase in the nasolabial angle, even though the correlation was very weak. The increase in the IMP angle was followed by an increase in the mentolabial angle, which was also very weakly correlated.

Long-term stability of Class III malocclusion nonextraction treatment

BackgroundThe aim of this study was to evaluate the long-term stability of successful therapy of patients with Class III malocclusion at the end of facial growth. Materials and methodsThe experimental group comprised 18 patients with Class III malocclusion treated without extractions with a mean age of 11.8 years (SD 2.8) at pretreatment, 15.7 years (SD 1.8) at posttreatment, and 24.1 years (SD 5.4) at follow-up. The control group comprised 22 subjects with normal occlusion observed during a comparable period. Intragroup treatment changes were analyzed with paired t tests, and intergroup posttreatment changes were compared with t tests. A multiple regression analysis was used to evaluate the influence of all variables in the amount of overjet relapse. ResultsIn the long-term, the experimental group demonstrated no significant change in apical base relationship. A significant decrease in overjet and overbite was observed but both remained positive. The primary factor that contributed to the overjet decrease was the mandibular growth in the posttreatment period. There were no significant intergroup differences regarding skeletal changes during the posttreatment period; however, the maxillary and mandibular incisors had significantly different behavior in the experimental as compared with the control group. ConclusionsIn the long-term, nonextraction Class III malocclusion treatment demonstrated clinical stability in 88.9% of the patients. The dentoskeletal improvements obtained with treatment remained stable during the posttreatment period. The greater amount of mandibular growth after active treatment was the major variable that determined instability of Class III malocclusion treatment.

Impact of Mouthwashes on Antibacterial Activity of Subjects with Fixed Orthodontic Appliances: A Randomized Clinical Trial.

The study aimed to assess the impact of mouthwashes on antibacterial activity of individuals with fixed orthodontic appliances. A total of 60 individuals were considered in the study. Sixty (20 each group) nonextraction class I individuals were randomly divided into experimental and control groups. Group I: Experimental group [chlorhexidine (CHX) mouthwash], group II: Experimental group (neem mouthwash), group III: Control group (distilled water). All the clinical examinations were done at baseline and 30th day respectively, after the start of orthodontic treatment. The mean differences between the different experimental groups were calculated using one-way analysis of variance (ANOVA) test. There was no statistical significance at baseline mean plaque index (PI), gingival index (GI) scores, and Streptococcus mutans (SM) colony count between groups. The PI and GI scores among CHX and neem mouthwash groups (p = 0.002, p = 0.032 respectively) were significantly reduced after intervention and also the SM colonies count was reduced in CHX and neem mouthwash groups and there was significant difference between the groups. As both mouthwashes showed significant effectiveness on antibacterial activity in individuals with fixed orthodontic appliances, neem mouthwash can be used as an alternative to CHX. It is better to have a sound knowledge regarding the use of mouthwash in long term as fixed orthodontics are associated with accumulation of SM, enamel demineralization, and an increased number of carious lesions, predominantly in sites adjacent to bracket.

A comparison of orthodontic elastic forces: Focus on reduced inventory.

OBJECTIVES:To compare orthodontic elastics with different force extension characteristics, thereby aiming to reduce the orthodontist's inventory for elastics.MATERIALS AND METHODS:Thirty nonextraction class I models were used to determine extension distances. Light, medium, and heavy forced Latex elastics of size 1/4 and 3/16 (from three manufacturers) were used. Thirty elastics from each pack were selected, for a total sample size of 540 elastics. Elastic force was measured at three extensions: three times the lumen (A), first molar to opposing canine (B), and second molar to opposing canine distance (C). Force values were compared with the analysis of variance followed by the post hoc Scheffe test.RESULTS:Mean distance for extensions B and C were 22.3 and 38.7 mm, respectively. There was a continuous but significant increase in the force of 1/4 elastics when stretched from A to extension C. A significant increase in the force level of 3/16 elastics was only noted when stretched from A to B. Overall, 1/4 elastics had a wider range of force coverage in the extensions used, compared to 3/16 elastics.CONCLUSIONS:The use of 1/4 elastics is sufficient to cover the range of forces in orthodontic treatment.

Treatment outcomes after extraction and nonextraction treatment evaluated with the American Board of Orthodontics objective grading system

A controversy exists regarding better treatment outcomes when patients treated with extractions and without extractions are evaluated. The aims of this study were to use the American Board of Orthodontics objective grading system (ABO-OGS) to evaluate and compare treatment outcomes in extraction vs nonextraction Class I patients and to determine whether the treatment choice was a significant predictor of success according to the ABO examination. Discriminant analysis was applied to a sample of 542 patients, and a borderline sample of 55 patients was obtained. Of these patients, 25 were treated with extractions and 30 without extraction of the 4 first premolars. Treatment results were then assessed using the 8 variables of the ABO-OGS. The total scores ranged from 11 to 41 (mean, 27.04; SD, 6.3) for the extraction group and from 16 to 44 (mean, 29.07; SD, 7.1) for the nonextraction group. The variable of buccolingual inclination had the highest scores in both groups (8.44 [SD, 3.3] for the extraction group; 8.90 [SD, 3.8] for the nonextraction group; mean difference, 0.46; 95% CI, -1.44, 2.37; P=0.63). However, no statistically significant intergroup differences were found, either between the scores of the 8 ABO-OGS variables or between the total ABO-OGS scores. Regarding the success rates of the ABO examination, no significant difference was found between the 2 treatment groups (odds ratio, 2.55; 95% CI, 0.74, 0.85; P=0.14). For a patient with a borderline Class I malocclusion, extraction and nonextraction treatment can achieve the same quality of results as assessed by the ABO-OGS. Additionally, in these Class I patients, the treatment modality (extraction or nonextraction) is not a significant predictor of passing the ABO examination.

Space supervision and guidance of eruption in management of lower transitional crowding: A non-extraction approach

Mandibular incisor crowding in the mixed dentition is one of the most common problems presenting to the orthodontist. Asymmetry of alignment, premature loss of primary canine(s), and disruption in arch integrity are all early benchmarks of a tooth size/arch length discrepancy in the transitional dentition that can occur independent of any skeletal discrepancy. Space supervision and guidance of eruption refer to treatment interventions during the early to mid-mixed dentition periods that influence the eruption patterns and positioning of the permanent teeth during their transition. Generally considered applicable to individuals with adequate overall arch dimensions to accommodate a normal complement of permanent teeth with an acceptable esthetic and functioning occlusion, guidance of eruption involves the implementation of directed interventions to optimize the eruption and alignment patterns of the permanent teeth as part of a non-extraction protocol.

Stability of molar relationship after non-extraction Class II malocclusion treatment

This study aimed to evaluate the stability of molar relationship after non-extraction treatment of Class II malocclusion. The sample comprised 39 subjects (16 females, 23 males) with initial Class II malocclusion treated with no extractions, using fixed appliances. Mean age at the beginning of treatment was 12.94 years, at the end of treatment was 15.14 years and at post-retention stage was 21.18 years. Mean treatment time was 2.19 years and mean time of post-treatment evaluation was 6.12 years. To verify the influence of the severity of initial Class II molar relationship in stability of molar relationship, the sample was divided into two groups, one presenting a ½-cusp or ¾-cusp Class II molar relationship, and the other with full-cusp Class II molar relationship. In dental casts from initial, final and post-retention stages, molar, first and second premolars and canine relationships were measured. Data obtained were analyzed by dependent ANOVA, Tukey and Pearson's correlation tests, as well as independent t test between the two groups divided by severity of initial molar relationship. There was a non-statistically significant 0.12-mm relapse of molar relationship. The initial severity of Class II molar relationship was not correlated to relapse in the post-retention period. When compared, the two groups showed no difference in relapse of molar relationship. It was concluded that correction of Class II molar relationship is stable and initial severity does not influence relapse of molar relationship.

A Prospective Clinical Trial of Arch Width Changes Evaluated through Dental Casts in Consecutively Treated Non-extraction and Extraction Cases

Objective: To compare the dental arch width changes in consecutively treated extraction and non-extraction Class I patients. Materials and methods: Anterior and posterior arch widths of the maxillary and mandibular arches of 21 patients treated by 4 first-premolar extraction and 20 patients treated without extractions were measured on study models using a digital caliper.The initial mean ages were 13.4 ± 1.02 years for the extraction group and 13.1 ± 1.7 years for the non-extraction group. Mean treatment time was 2.7 ± 0.6 years for the extraction group and 2.4 ± 1.0 years for the non-extraction group. The maxillary and mandibular crowding were −5.2 ± 2.8 and −5.9 ± 3.1 mm for the extraction group and −4.1 ± 2.7 and −3.3 ± 2.5 mm for the non-extraction group, respectively. To compare the changes between groups, independent samples t-tests were performed. Results: At the end of treatment, no differences were found between the groups in maxillary intercanine width. The maxillary and mandibular intermolar widths decreased significantly for the extraction group (-0.74mm and -1.59mm, respectively) compared with non-extraction (1.30mm and 0.37mm, respectively). The mandibular intercanine width increased significantly for the extraction group (1.48mm) compared with non-extraction group (0.52mm). Conclusions: Orthodontic treatment with extractions of four first premolarsin Class I patients provided no significant difference in maxillary intercanine width after treatment compared to nonextraction. However, nonextraction treatment produced significantly larger values in maxillary and mandibular intermolar widths than that in the extraction group.

Class II Non-Extraction Patients Treated with the Forsus Fatigue Resistant Device Versus Intermaxillary Elastics

To evaluate the Forsus Fatigue Resistant Device (FRD) as a compliance-free alternative to Class II elastics. A sample of 34 (14 female, 20 male) consecutively treated nonextraction FRD patients (12.6 years of age) were matched with a sample of 34 (14 female, 20 male) consecutively treated nonextraction Class II elastics patients (12.2 years of age) based on four pretreatment variables (ANB, L1-GoMe, SN-GoMe, and treatment duration). Pretreatment and posttreatment cephalometric radiographs were traced and analyzed using the pitchfork analysis and a vertical cephalometric analysis. t-Tests were used to evaluate group differences. Group differences were evaluated using t-tests. No statistically significant differences were found in the treatment changes between the groups. There was a general trend for mesial movement of the maxilla, mandible, and dentition during treatment for both groups. The mandibular skeletal advancement and dental movements were greater than those in the maxilla, which accounted for the Class II correction. Lower incisor proclination was evident in both groups. Vertically, the maxillary and mandibular molars erupted during treatment in both groups, while lower incisors proclined. With the exception of lower molar mesial movements and total molar correction, which were significantly (P < .05) greater in the Forsus group, there were no statistically significant group differences in the treatment changes. The Forsus FRD is an acceptable substitute for Class II elastics for noncompliant patients.

Extraction versus non-extraction: evaluation by digital subtraction radiography

The aim of this study was to investigate the facial profile changes of patients treated with and without extractions of four first premolars using novel computer-based digital subtraction software. The pre- and post-treatment radiographic image pairs of 25 extraction (13 girls and 12 boys, mean age = 12.64 +/- 1.82 years) and 24 non-extraction (12 girls and 12 boys, mean age = 12.48 +/- 1.66 years) Class I patients were subtracted by the software. Student's t-tests were used to determine whether the subtraction values for the linear measurements of radiographic differences registered at various anatomical landmark parameters were statistically different between the groups. To further determine whether any variables related to upper and lower lip changes, regression analyses were performed. The main soft tissue differences between the groups were established at labrale superior, labrale inferior, and sulcus inferior points, with extraction patients showing significantly more retruded upper and lower lips. However, the mean differences between the groups did not exceed 1 mm for these variables. Changes at labrale superior and labrale inferior were associated with sagittal movement of the maxillary (r = 0.549) and mandibular (r = 0.630) incisor midpoints. Changes at sulcus inferior were associated with both sagittal and vertical displacement of mandibular incision point (r = 0.676). Some dentofacial alterations were found but in view of the differences between the groups pretreatment, the inter-group differences reflect different treatment intent rather than differences arising from the extraction and non-extraction modalities.

A strategy for nonextraction class II treatment

Class II nonextraction treatment, which commonly includes distal movement of the maxillary molars to correct the molar relationship, most often can be successful when treatment is started in the late-mixed dentition stage of development. At least two factors contribute to this success. One is that the molars can be distalized routinely at this age. The second is that the “E” space is available and can be used either to help correct the molar relationship or to resolve any crowding that may exist. This article describes and illustrates the treatment of a late mixed-dentition patient with this type of Class II nonextraction treatment that includes distal movement of the maxillary molars with a 100 g NiTi coil system and the maintenance of the “E” space with a lip bumper.

Profile changes in patients treated with and without extractions: Assessments by lay people

The purpose of this study was to assess the profile changes in subjects with Class II, Division 1 malocclusions who were treated either with or without the extraction of the four first premolars. The assessments were made by 39 lay persons. Profile silhouettes on 91 (44 extraction and 47 nonextraction) patients were evaluated at three stages: pretreatment, posttreatment, and approximately 2 years after treatment. Photographs matched for age and sex were also evaluated on 20 normal untreated subjects (10 males and 10 females). All rater assessments were analyzed statistically as to the effects of the following variables: (a) occlusion, i.e., normal or Class II, (b) treatment rendered, i.e., extraction or nonextraction, (c) gender, i.e., male or female, and (d) stage of observation, i.e., pretreatment, end of treatment or in retention. The current findings indicate that (1) before treatment, lay persons perceived the profile of normal patients more favorably than untreated patients with Class II, Division 1 malocclusions. (2) Immediately after treatment, raters perceived the changes in the profile of the extraction group more favorably than those in the nonextraction and normal groups. (3) At the end of the observation period (approximately 2 years posttreatment), raters did not evaluate the profile of any of the groups as being more favorable, but all groups were perceived more favorably than at the initial observation. (4) Raters perceived the profile changes with treatment more favorably in female subjects than in male subjects. In conclusion, orthodontic treatment seems to have a favorable effect on the profiles of both the extraction and nonextraction groups, both short- and long-term. Therefore, when based on proper diagnostic criteria, the posttreatment changes in the facial profile were perceived as favorable in both the extraction and nonextraction Class II, Division 1 groups when compared with the pretreatment profile. (Am J Orthod Dentofac Orthop 1997;112:639-44.)

A comparison of one-stage and two-stage nonextraction alternatives in matched Class II samples

In the treatment of Class II malocclusion, an early phase of functional appliance treatment is commonly used to simplify subsequent fixed appliance therapy and to optimize the development of the facial skeleton. Unfortunately, these expectations enjoy little support in the refereed literature. The present study therefore was undertaken to examine the benefits of a two-stage bionator/edgewise regimen in comparison to the more conventional one-stage edgewise alternative. To minimize proficiency bias, we examined the records of the one- and two-stage Class II nonextraction patients who received treatment between 1980 and 1990 by a single experienced clinician. On the basis of descriptive data from 96 sets of initial study models and lateral cephalograms, discriminant analysis was used to identify two subsamples of 36 patients who were relatively similar before treatment and thus equally susceptible to the two treatments. Of these 72 “borderline” patients, 19 subsequently underwent a change in treatment plan (to extraction or surgery), leaving 25 two-stage and 28 single-stage nonextraction patients on whom to base a comparison of treatment effects. Except for a slight posttreatment difference in age (and, hence, size), the two groups underwent skeletal changes that left them essentially indistinguishable at the end of treatment. In both groups, these skeletal changes were largely responsible for molar and overjet corrections that were nearly identical in the two groups. The rates of change, however, differed significantly. As a result, the two-stage treatments started earlier and finished later. Although the present data do not address the relative impact of the two strategies on the 10% to 15% at each tail of the distribution, the early phase of functional appliance treatment conferred no obvious, measurable benefits on the central 75%. Therefore for most nonextraction Class II patients, the choice of treatments may well constitute a practice management, rather than a biologic, decision. (A M J O RTHOD D ENTOFAC O RTHOP 1995;108:118-31.)

Nonextraction Class II, Division 2 treatment

The final evaluation of all orthodontic treatment depends on successful retention and on how well the teeth retain their new positions several years after the retainers have been removed. To assure stability in this type of case, the mandibular posterior teeth were uprighted to be parallel with the muscles of mastication, thus reducing any mesial forces which would again crowd the anterior teeth.The correction of the interincisal angle to 128 degrees provided an incisal stop to prevent the deep overbite from recurring in the anterior region. The patient was instructed to swallow with a normal tongue position. The correction of the lateral tongue thrust prevented the recurrence of a deep curve of Spee. To eliminate the lateral tongue thrust, the posterior teeth were extruded to close the excess freeway space, but not so far as to encroach on the normal freeway space. The tongue was thus prevented from coming between the posterior occusal surfaces during deglutition.All of these factors contributed to the stabilization of the dentition. Uprighting the posterior teeth and proper torquing of the incisors permitted treatment to be accomplished without extraction of the premolars without causing a “dishing” of the face.