Cephalometric Investigation Research Articles

Outcome differences after orthodontic camouflage treatment in hypo- and hyperdivergent patients – A retrospective cephalometric investigation

ObjectivesTo compare differences in outcome in skeletal and dental parameters in hypo- and hyperdivergent Class II patients after extraction of upper first premolars and comprehensive orthodontic treatment.Materials and methods37 Class-II-patients with dental camouflage treatment were divided into a hypo- (n = 18) or a hyperdivergent (n = 19) group depending on the mandibular plane angle (hypo: < 34° or hyper: ≥ 34°). Lateral cephalograms were available before (T1) and after (T2) treatment and were analyzed with customized measurements. Data from a growth survey served as a control and were used to calculate the actual treatment effect. Data were analyzed by one-sample Student’s t-tests and independent Student’s t-tests. Statistical significance was set at p < 0.05.ResultsThe measurements showed similar changes in both groups. The effects were mainly dentoalveolar. Hypodivergent patients showed an almost equal increase in anterior and posterior facial height, while hyperdivergent patients only showed an increase in anterior facial height.ConclusionsIn hyperdivergent patients, the anterior facial height increases despite camouflage treatment. This indicates a tendency towards bite opening and backward rotation of the mandible. Hypodivergent patients do not experience deepening of the bite.Clinical relevanceIn hyperdivergent patients with upper first premolars extraction the anterior facial height increased differently than in hypodivergent patients. This should be considered if a bite opening is a possible contraindication to treatment.

Effects of fixed functional orthodontic treatment in hypodivergent and hyperdivergent class II patients—a retrospective cephalometric investigation

ObjectiveTo compare skeletal and dentoalveolar changes after orthodontic treatment of class II malocclusion in patients with hypodivergent and hyperdivergent growth patterns through cast splint fixed functional appliances (FFA).Materials and methodsN = 42 out of n = 47 patients with mandibular plane angles < 34° or ≥ 34° were divided into a hypodivergent (n = 24) and a hyperdivergent (n = 18) group. All patients received a single-step mandibular advancement protocol through an FFA. Lateral cephalograms were analyzed after initial leveling and alignment (T1) and immediately after FFA removal (T2). The therapeutic effect was calculated through comparison with age-matched controls from a growth survey. Statistical significance was set at p < 0.05.ResultsHypodivergent and hyperdivergent patients showed different treatment outcomes, but significant differences existed only for overbite and interincisal angle. Nearly all measurements suggested similar treatment-related changes for both groups with exception for dentoalveolar parameters.ConclusionTreatment with FFA causes similar skeletal and dentoalveolar effects in hypodivergent and in hyperdivergent patients. The correction of overjet and molar relationship is mainly caused by dentoalveolar changes.Clinical relevanceHyperdivergent patients do not respond unfavorably to FFA treatment compared to hypodivergent patients. Lower incisor protrusion occurs more pronounced in hypodivergent patients. The growth pattern ought to be considered when choosing FFA for class II treatment.

The genetic and environmental interaction behind malocclusion: Case report of two twins

Background: Genetic and environmental contribution in the etiology and shape of malocclusion has long been a controversy for the authors. In fact, even though craniofacial deformations are the result of both genetic and environmental factors, there is irrefutable evidence for the high genetic control on craniofacial development and for the significant genetic influence in many dental, occlusal and skeletal variables. The aim of this twin’s case report is to clinically show the role of each of these two factors on the expression of abnormalities and particular traits. Case presentation: The case reflect 10-year-old twins who consulted for their anterior overlap. The comparison between the twins is done through clinical and cephalometric investigation. The clinical examination revealed a great resemblance between the two patients both at the extra-oral (ortho-frontal profil, nasolabial angle, the shape of the forehead, cervico-chin distance) and intra-oral view (Palato- position of the maxillary lateral incisors, molar class I, mandibular arch perfectly identical with mirror effect), Cephalometric analysis revealed a very high morphological similarity (identical skeletal class III, biproalveolia, hyperdivergenc and the position of mandibular incisor). Conclusion: The existence of a very important genetic control on craniofacial development and the installation of dysmorphosis is undeniable, in particular on skeletal class III and hyperdivergence. But the severity of these dysmorphosis can also be increased by environmental and behavioral factors.

Effects of nicotine exposure on murine mandibular development.

Nicotine is known to affect cell proliferation and differentiation, two processes vital to proper development of the mandible. The mandible, the lower jaw in mammals and fish, plays a crucial role in craniofacial development. Malformation of the jaw can precipitate a plethora of complications including disrupting development of the upper jaw, the palate, and or impeding airway function. The purpose of this study was to test the hypothesis that in utero nicotine exposure alters the development of the murine mandible in a dose dependent manner. To test this hypothesis, wild type C57BL6 mice were used to produce in utero nicotine exposed litters by adding nicotine to the drinking water of pregnant dams at concentrations of 0 μg/ml (control), 50 μg/ml (low), 100 μg/ml (medium), 200 μg/ml (high) throughout pregnancy to birth of litters mimicking clinically relevant nicotine exposures. Resultant pups revealed no significant differences in body weight however, cephalometric investigation revealed several dimensions affected by nicotine exposure including mandibular ramus height, mandibular body height, and molar length. Histological investigation of molars revealed an increase in proliferation and a decrease in apoptosis with nicotine exposure. These results demonstrate the direct effects of nicotine on the developing mandible outside the context of tobacco use, indicating that nicotine use including tobacco alternatives, cessation methods, and electronic nicotine delivering products may disrupt normal growth and development of the craniofacial complex.

Evaluation of Sagittal Changes in Class II Div 2 Patients with Decelerating Phase of Growth by PowerScope Appliance: A Retrospective Cephalometric Investigation.

Background:Restricted mandibular growth is observed in Class II Div 2 malocclusions. The fixed functional appliances are used to effect the skeletal changes in patients with end stages of skeletal maturity.Aim:This cephalometric study aimed to distinguish the skeletal and dental corrections done in the mandible on skeletal Class II Div 2 subjects when treated with PowerScope appliance (American Orthodontics, Sheboygan, WI).Materials and Methods:This is a cephalometric study based on the retrospective data. The patients selected for this study were with Class II Div 2 malocclusion and assessed to be in decelerating phase of skeletal growth. A total of 12 patients were selected after applying inclusion and exclusion criteria. A PowerScope was placed after incisor correction and followed up till Class I molar relation was achieved. The initial values (T1) at the time of placement of the appliance and the final values at the end of the molar correction (T2) were noted. The cephalometric parameters at T1 and T2 were assessed using sagittal occlusal (SO) analysis by Pancherz. The paired Student’s t-test was used to analyze pre- and posttreatment changes.Results:There was sufficient lengthening of the mandible (4.38 mm). Both the dental and skeletal alterations were observed in the mandible. These changes were marked compared to the maxilla. The pre- and posttreatment changes were statistically significant for the mandibular skeletal changes (P < 0.001) as well as mandibular incisor proclination (P < 0.001).Conclusion:The PowerScope can be used as a propeller for sagittal mandibular correction in Class II Div 2 patients.

Cephalometric appraisal of post-treatment tooth eruption: a 20 year follow-up study.

To assess the amount of tooth eruption that occurs during 20 years after completion of orthodontic treatment and analyse possible correlations with age and mandibular growth pattern present. A retrospective longitudinal cephalometric investigation of dento-alveolar changes was performed in 72 patients (50 women and 22 men). Two lateral cephalograms, taken at the end of orthodontic treatment and on average 20 years later, were available for each subject. The mean age at the beginning of the observation period was 21.5 years and the mean observation period was 19.7 years. Changes in the cephalometric measurements were evaluated statistically. For all parameters, there is evidence for an increase in tooth eruption parameters during the 20 year interval. Furthermore, a significant difference in change was found between different growth patterns for all parameters. For the majority of the parameters, the increase is higher for subjects being younger at the end of orthodontic treatment. There is no evidence for a difference in change between males and females. Continued tooth eruption readily occurs after termination of orthodontic treatment in all patients. There is a correlation between the mandibular growth pattern present and the amount of tooth eruption in posterior and anterior regions in both the mandible and the maxilla after completion of the orthodontic treatment. These changes are more pronounced in patients treated orthodontically during adolescence.

Cephalometric investigation of craniomaxillofacial structures during the prenatal period: A cadaver study

We aimed to investigate the morphometric development of the cranial base and its related structures, and their growth rate changes from the ninth gestational week to full term in a large group of human fetuses. We selected 203 (109 male, 94 female) fetuses between 9 and 40 weeks of gestation and without any external anomalies. From each fetus, standard lateral and posteroanterior cephalometric images were taken using a dental digital panoramic and cephalometric x-ray machine. Fourteen linear and 9 angular parameters were measured. The cranial base angle showed a statistically significant increase between the groups from only the second to the third trimester periods. The sagittal translation of the maxilla increased during the prenatal period, whereas the mandibular sagittal relation grew at a steady rate. The vertical plane angles of the maxilla and the mandible did not show any significant changes. The maxillary length to mandibular length ratio remained stable. The cranial base angle increased, especially in the second through the third trimesters. The maxilla and the mandible demonstrated different growth patterns in the sagittal direction. The findings of this study could be a guide for interpreting the relationships among the craniofacial structures.

Cephalometric investigation of first cervical vertebrae morphology and hyoid position in young adults with different sagittal skeletal patterns.

The aim of this retrospective study was to examine hyoid bone position and C1 (atlas) morphology in males and females and analyze these parameters with respect to different sagittal skeletal patterns via cephalometry, with the goal of identifying cephalometric norms. Lateral cephalometric radiographs from 120 individuals (average age: 21.1 ± 2.9 years) were classified according to their ANB angle (Class I, II, or III) and used to assess 14 parameters. Class I and II patients showed significant differences in Hy-NSL, Hy-PD, Hy-CVT, Lum, and a-p measurements. These parameters were consistently larger in males than in females. Intergroup comparisons among males showed significant differences in the SNA, ANB, Hy-CVT, X, and Z measurements. The hyoid was positioned more inferiorly and anteriorly and was more prominent in males than in females in all groups. Among participants exhibiting a Class I skeletal pattern, C1 was also larger in the anterior-posterior direction in males than in females. In the sagittal plane, the hyoid was positioned similarly in males with either Class I or III skeletal patterns but was positioned posteriorly in males with a Class II skeletal pattern. In addition, the vertical position of C1 varied with sagittal skeletal pattern in males.

A cephalometric investigation of horizontal lip position in adult Nigerians

The aims of this study were to (1) identify soft tissue cephalometric norms for horizontal lip position in an adult Nigerian population; (2) compare values for Nigerian males and females; and (3) compare Nigerian norms with established norms for Caucasians and other populations. A cross-sectional descriptive study. Lagos University Teaching Hospital Dental Clinic, Idi-araba, Lagos, Nigeria. One hundred students (44 males and 56 females) of the College of Medicine, University of Lagos, aged 18-25 years, of Nigerian ancestry, with a normal class I occlusion and no facial asymmetry. Lateral cephalometric radiographs of the subjects were taken in natural head position. Radiographs were manually traced and 11 soft tissue cephalometric parameters measured. These were derived from the Steiner, Ricketts, Burstone, Merrifield and Holdaway soft tissue analyses. Male and female values were compared using Student's t-test with a level of significance at P<0·05. Statistically significant differences were observed between Nigerian males and females in eight of the variables studied, with males having more protrusive upper and lower lips than the females. Variables, which did not vary by sex, were soft tissue facial angle, nose prominence and soft tissue chin thickness. In addition, Nigerian norms were higher than norms reported by Steiner, Ricketts, Burstone and Holdaway for Caucasian populations, while the Z-angle was lower than the norm established by Merrifield. Gender-specific soft tissue norms for horizontal lip position should be used for orthodontic treatment planning in Nigerian subjects. Nigerians have more protrusive upper and lower lips compared to Caucasians.

Over-bite and Vertical Changes following First Premolar Extraction in High Angle Cases

Orthodontists generally agree that nonextraction treatment is associated with downward and backward rotation of the mandible and an increase in the lower anterior face height (LAFH). They also agree that extraction line of treatment is associated with upward and forward rotation of the mandible and decrease in the LAFH. The intent of this cephalometric investigation was to examine the wedge hypothesis, that the vertical dimension collapses after first bicuspid extraction. The present study was undertaken to evaluate the cephalometric overbite and vertical changes following first premolar extraction in high angle cases. Forty-five adult patients having high mandibular plane angle, i.e. Gogn--SN more than or equal to 32° having class I molar and canine relation were included. Pre and post-treatment lateral cephalograms were measured and compared to analyze the cephalometric changes. There was no decrease in the overbite and vertical changes following first premolar extraction in high angle cases. The facial complex does increase in size with growth, but mandibular plane while moving inferiorly, remain essentially parallel to its pretreatment position due to residual growth and treatment mechanics. The study concluded that, There was no decrease in the vertical facial dimension, overbite and mandibular plane angle. However, it should be interpreted with caution, given the small sample size.

Comparison of the cephalometric posterior airway analysis with endoscopic tongue base hypertrophy findings in patients with obstructive sleep apnea syndrome

This study aims to identify the contribution of the cephalometric investigation in the soft tissue evaluation in patients with obstructive sleep apnea syndrome (OSAS). The clininical data of 300 patients (191 males, 109 females; mean age 48.3±9.9 years; range 24 to 76 years) diagnosed with OSAS in our clinic between January 2009 and May 2010 were retrospectively evaluated. All subjects in the test group had overnight polysomnography, cephalometry and flexible endoscopic examination. Distance and angle calculations were performed with the previously determined landmarks on cephalograms. The degrees of tongue base hypertrophy were recorded in the flexible endoscopic examinations. Posterior airway space calculations were compared with tongue base hypertrophy findings by using chi-square analysis. The mean apnea hypopnea index (AHI) score and the mean supine AHI were calculated to be 24.7 and 26.5, respectively. According to the endoscopic examination, the tongue base hypertrophy was grade 0 in 20 patients (6.6%), grade 1 in 60 patients (20%), grade 2 in 122 (40.6%) patients and grade 3 in 98 (32.6%) patients. The posterior airway space value calculated to be 4 mm at minimum and 15 mm at maximum. When the cephalometric measurements of the patients were compared with the magnitude of tongue base hypertrophy detected by endoscopic examination, it was determined that the relationship with the size of the tongue base decreases as the posterior airway space increases. Cephalometric investigation, which is known as adjunct technique in the soft tissue evaluation, does not provide adequate information in the evaluation of the OSAS patients.

Effects of mandibular protraction appliance-IV in the treatment of class II malocclusion: A cephalometric investigation

To evaluate the nature of Class II correction with MPA-IV in the treatment of Class II Division 1 malocclusions. Twenty-five subjects in the age range of 10–12 years were chosen for the study. The subjects were divided among control group (n=10) and treatment group (n=15). Prefollow-up and postfollow-up lateral cephalograms of control subjects, and pretreatment and posttreatment lateral cephalograms of the treatment subjects, were traced manually and sUbjected to the pitchfork analysis. MPA-IV signiflcantly restricted the forward growth of maxilla (p Conclusions: Mandibular protraction appliance IV was an effective fixed functional appliance in the correction of Class II Division 1 malocclusion. However, subjects who can tolerate greater dentoalveolar compensation for the correction of their Class II malocclusion are best tronted with mandibular protraction appliance IV.

Rapid maxillary expansion in growing patients. Hyrax versus transverse sagittal maxillary expander: a cephalometric investigation

The aim of this retrospective study was to cephalometrically evaluate and compare the skeletal and dental effects of a transverse sagittal maxillary expander (TSME) and a Hyrax-type expander (RME) in children with maxillary hypoplasia. Fifty subjects (26 males and 24 females), aged from 6 to 15 years, with a maxillary crossbite caused by basal apical narrowness, were divided into two equal groups. Twenty-five were treated with a TSME and the other 25 with a RME. For each patient, a lateral cephalogram was obtained before treatment (T0) and at the end of the retention period (T1). Changes in the two groups during the observation period were calculated, compared, and statistically analysed with a paired samples t -test. In the TSME group, SNP-A, I SN, and I FH and in the RME group SN-SNP.SNA, N-Me, and U6.PP displayed a statistically significant increase (P < 0.05). The increase in SNP-A, I SN, and I FH in the TSME group was significantly greater following treatment than in the RME group. The results support the use of the TSME to produce skeletal changes and dentoalveolar modification and to correct maxillary hypoplasia. It was also demonstrated that in patients with an anterior open bite, the use of the TSME is not contraindicated as the anterior vertical dimension did not increase significantly.

Dentofacial effects of bone-anchored maxillary protraction: A controlled study of consecutively treated Class III patients

In this cephalometric investigation, we analyzed the treatment effects of bone-anchored maxillary protraction (BAMP) with miniplates in the maxilla and mandible connected by Class III elastics in patients with Class III malocclusion. The treated sample consisted of 21 Class III patients consecutively treated with the BAMP protocol before the pubertal growth spurt (mean age, 11.10 ± 1.8 years) and reevaluated after BAMP therapy, about 1 year later. The treated group was compared with a matched control group of 18 untreated Class III subjects. Significant differences between the treated and control groups were assessed with independent-sample t tests (P <0.05). Sagittal measurements of the maxilla showed highly significant improvements during active treatment (about 4 mm more than the untreated controls), with significant protraction effects at orbitale and pterygomaxillare. Significant improvements of overjet and molar relationship were recorded, as well as in the mandibular skeletal measures at Point B and pogonion. Vertical skeletal changes and modifications in incisor inclination were negligible, except for a significant proclination of the mandibular incisors in the treated group. Significant soft-tissue changes reflected the underlying skeletal modifications. Compared with growth of the untreated Class III subjects, the BAMP protocol induced an average increment on skeletal and soft-tissue advancement of maxillary structures of about 4 mm, and favorable mandibular changes exceeded 2 mm.

Treatment and posttreatment effects of a facial mask combined with a bite-block appliance in Class III malocclusion

In this cephalometric investigation, we analyzed the treatment and posttreatment effects of an orthopedic protocol for Class III malocclusion consisting of a facial mask combined with a removable bite-block appliance. The treated sample consisted of 22 Class III patients treated with the facial mask and bite-block protocol before the pubertal growth spurt (mean age, 8.9 +/- 1.5 years). Treated subjects were evaluated after facial mask and bite-block therapy and at a posttreatment observation in absence of retention. The treated group was compared with a matched control group of 12 untreated Class III subjects. All treated and control subjects were postpubertal at the final observation. Significant differences between the treated and control groups were assessed with the Mann-Whitney U test (P <0.05). Both angular and linear sagittal measurements of the maxilla showed significant improvements during active treatment. Significant improvements of SNA angle, ANB angle, overjet, and molar relationship remained stable during the posttreatment period. No significant effect was found in the mandibular skeletal measures. No significant protraction of the maxillary incisors or retraction of the mandibular incisors was observed. A bite-block appliance in the mandibular arch with a facial mask enabled effective control of mandibular rotation with progressive closure of the gonial angle. This added to the favorable maxillary outcomes of the treatment protocol.

HUBUNGAN ANTARA KEDALAMAN SINUS FRONTALIS DAN MATURASI TULANG TANGAN: CORRELATION BETWEEN FRONTAL SINUS DEPTH AND HAND WRIST MATURITY

The appropriate planning of orthodontic therapy with regard to appliance selection, information on the patient’s stage ofsomatic maturity is needed. Hand wrist maturity has been shown to be closely related with the pubertal growth spurt;therefore hand wrist radiographs have been recommended for indirect assesment of somatic maturity. However, theroutine use of hand wrist radiographs has lately been questioned from the radiation-hygiene, safety point of view. In arecent cephalometric investigation, it was found that the frontal sinus development showed a growth rhythm similar to thebody height development. Furthermore, it has been proposed that frontal sinus enlargement follows general bone growthbut little evidence has been shown. The objective of this study was to investigate the correlation between frontal sinusdepth and hand wrist maturity in Deuteromalayid group aged 7 to 17 years. A cross sectional study was conducted in 138subjects (69 males, 69 females). The frontal sinus depth and hand wrist maturation was determined using Erturk’s andFishman’s method, respectively. The result of this study showed that there was a moderate correlation between frontalsinus depth and hand wrist maturity in males (r = 0.608) and females (r = 0.647). From this study, it can be concludedthat the usage of frontal sinus depth to substitute hand wrist maturity to assess the skeletal maturity is not appropriateenough.

Treatment and posttreatment effects of mandibular cervical headgear followed by fixed appliances in Class III malocclusion

In this cephalometric investigation, we compared the treatment and posttreatment effects on patients undergoing an initial phase of mandibular cervical headgear (MCH) therapy followed later by comprehensive edgewise therapy with untreated Class III controls. The treated sample consisted of 21 patients treated consecutively with MCH before the pubertal growth spurt (average age, 10 years 2 months at the beginning of treatment). At the final observation period (average age, 15 years 3 months), all patients were in decelerative growth phases as determined by the cervical vertebral maturation method. Active treatment and posttreatment effects were evaluated in the treated group with nonparametric statistical analysis for paired samples. The treated sample was compared with a nonparametric statistical test for independent samples with 20 untreated Class III subjects who were matched for malocclusion, sex, and stage of cervical vertebral maturation to the treatment group. MCH therapy followed by fixed appliances was shown to be an effective treatment for the correction of skeletal Class III malocclusion at postpubertal observation. The favorable skeletal effects consisted mainly of smaller increases in mandibular length and advancement with respect to the controls, with the final outcome of significant improvements in the sagittal skeletal (+4 mm for the Wits appraisal) and dental (+2.7 mm for overjet, -4.4 mm for molar relationship) parameters. This treatment protocol also induced significant downward rotation of the mandible (2.8 degrees ).

Vascular Endothelial Growth Factor (VEGF) in Human Tooth Germ Center

Many oncogenis and tumour suppressor genes found inside normal and pathological cells are fundamental for the processes of development, proliferation and tissue differentiation. The purpose of our study is to show the presence and a possible relationship of the VEGF protein during different phases of the development of human dental germ centers. After cephalometric investigation in 8 orthodontic patients with a mean age of 13 years, (4 females and 4 males), hyperdivergence of the third molars were extracted. The 40 surgical samples were tested with monoclonal human anti-VEGFs antibodies carrying out a semi-quantitative analysis to look for a positive reaction. Reaction for anti-VEGF antibodies was detected in normal embryological tissues and in microvessels near odontogenic cells. During different phases of embryologic development of the dental bud our search showed intracytoplasmatic positive immunoreactions both in the ameloblastic and odontoblastic cells. Additionally, a positive reaction was observed for the VEGF protein in the cells of the stellate reticulum and in those endothelial tissue surrounding the microvessels in all the samples examined.

Efficiency of three mandibular anchorage forms in Herbst treatment: a cephalometric investigation.

The aim of this study was to analyze the efficiency of the mandibular banded and cast splint anchorage forms used in Herbst treatment. The records of 16 Class II:1 subjects treated with mandibular banded premolar anchorage (group A), 19 Class II:1 subjects treated with mandibular banded premolar-molar anchorage (group B), 34 Class II:1 subjects (group C), and 18 Class 11:2 subjects treated with mandibular cast splint anchorage (group D) were screened. The subjects in all four groups were treated for an average period of 0.6 years. Lateral head films were analyzed on four occasions ie, before treatment, after treatment, two years after, and four years after treatment. Mandibular anchorage loss during treatment was measured by the amount of anterior movement and proclination of the lower incisors as well as the anterior movement of the lower molars. During the treatment period a pronounced (P < .001) anchorage loss was found for all anchorage forms ie, incisor anterior movement/proclination as well as anterior movement of the lower molars. When comparing the cast splint anchorage in the Class II:1 and Class II: 2 cases, no difference was found with respect to the amount of mandibular anchorage loss of the incisors. After Herbst treatment, relapsing tooth movements were found in all three anchorage forms. It can be concluded that none of the three mandibular anchorage forms used in Herbst treatment could prevent an anchorage loss. Against all expectations, the cast splint anchorage was not better than the two banded anchorage forms.

Influence of extraction and nonextraction orthodontic treatment in Japanese-Brazilians with class I and class II division 1 malocclusions

The primary objective of this retrospective, longitudinal, cephalometric investigation was to study the influence of extraction and nonextraction orthodontic treatment on the facial height of Japanese-Brazilian children with Class I and Class II Division 1 malocclusions. The sample included 59 mesocephalic patients distributed into 4 groups: group 1: Class I patients treated with 4 first premolar extractions; group 2: Class I patients treated nonextraction; group 3: Class II Division 1 patients treated with 4 first premolar extractions; group 4: Class II Division 1 patients treated nonextraction. The overall initial mean age of the groups was 12.14 years, and all groups were treated with standard edgewise appliances for a mean period of 2.49 years. The pretreatment and posttreatment stage comparison and the intergroup comparison of the treatment changes were conducted between extraction and nonextraction groups in the Class I and Class II malocclusion samples with t tests. The amounts of changes in the absolute magnitude of posterior and anterior facial heights and in the ratios of lower posterior facial height/lower anterior facial height and lower anterior facial height/total anterior facial height were similar between extraction and nonextraction treatment in both Class I and Class II malocclusions.