Dentoskeletal Pattern Research Articles

Facial Anthropometry and Aesthetic Preferences in Malay Women: A Comparative Study

The study aimed to explore the relationship between Malay females’ facial attractiveness with golden ratio, neoclassical canons, “ideal” ratios and “ideal” angles; and to compare self-perceived facial attractiveness and health-related quality of life (HRQoL) among Malay females with different skeletal patterns. Sixty-four young Malay female participants each completed a set of self-administered questionnaires and have five facial photographs taken. The self-assessed satisfaction with facial appearance and HRQoL were compared between participants with different dentoskeletal patterns. Seventy-seven facial anthropometry parameters related to the golden ratio, neoclassical canons, ideal ratios and ideal angles were measured. Subsequently, 15 sets of photographs representing different skeletal patterns were randomly selected. A panel of juries evaluated facial attractiveness using a 7-point Likert scale. The correlation between facial attractiveness and measured parameters was studied. Results indicated that mean rank FACE-Q Rasch scores of participants’ self-rated satisfaction on their facial appearance and HRQoL were not significantly different statistically (p = 0.06–0.81) between Class I, II and III. One hundred and eighty juries (mean 24.33±3.82 years old) were recruited. No statistically significant correlations found between facial attractiveness rated by juries and measured parameters related to the golden ratio (r = –0.47 to 0.36; p = 0.08 to 0.98), neoclassical canons (r = –0.27 to 0.43; p = 0.11 to 0.96), ideal ratios (r = –0.32 to 0.47; p = 0.08 to 0.96) and ideal angles (r = –0.23 to 0.28; p = 0.31 to 0.92). In conclusion, the study found that the golden ratio, neoclassical canons, ideal ratios, and ideal angles were not found to be correlated with the facial attractiveness of Malay females. Therefore, these guidelines should be used with discretion during treatment planning and outcome assessment for this specific ethnic group.

Quantitative analysis of the morphology of the lips according to different anteroposterior and vertical skeletal patterns

Objectives: The aim of this study was to compare the differences in the morphology of the lips according to anteroposte-rior dentoskeletal patterns and facial divergence.Materials and Methods: The samples were composed of the frontal facial photographs of 117 adult patients who satisfied all the cephalometric measurements for six groups (Class I or II or III and normodivergent or hyperdivergent). The morphol-ogy of the lips was evaluated on the frontal facial photographs and the measurements were compared between the groups.Results: In the normodivergent groups, the height-to-width ratio of the lip vermilion was significantly greater in the Class II group than in the Class I group, and the labrale superius angle and upper lip convexity of the Class II group was smaller than that of the Class I group. In the hyperdivergent groups, the stomion inferius angle of the Class III group was smaller than that of the Class II group. Lower facial height and the interlabial gap in the hyperdivergent groups tended to be larger than those in the normodivergent groups. The height-to-width ratio of the lip vermilion and the commissure height were larger in the hyperdivergent groups than in the normodivergent groups. However, the upper lip height and philtrum height did not differ between the hyperdivergent and normodivergent groups.Conclusion: The morphological characteristics of the lip vermilions on the frontal view differed according to the sagittal dentoskeletal relationship and facial divergence.

Comparison of treatment effects between two types of facemasks in early Class III patients.

To compare the short-term treatment effects between two types of facemasks in skeletal Class III patients. This retrospective study included 40 skeletal Class III subjects (mean age: 7.7 years) who had been treated with protraction facemasks with forehead straps (PFFS) or Petit type facemasks (PTF). Lateral cephalograms were analyzed at pretreatment (T1) and posttreatment (T2) with an average interval of 9 months. At T1, PFFS and PTF groups showed similar sagittal, vertical dentoskeletal patterns. From T1 to T2, both groups presented significant forward movement of the maxilla, posterior movement and clockwise rotation of the mandible (all p < .001), labioversion of the maxillary incisors, and linguoversion of the mandibular incisors. They showed increased overjet (p < .001). Although there were no significant differences in the number of changes in most dentoskeletal variables between the two groups, the PFFS group showed more anterior rotation of the palatal plane and backward rotation of the mandible compared to the PTF group, resulting in a significant decrease (-0.42 mm) in overbite (p < .05). Both PFFS and PTF showed no significant differences in most skeletal and dental changes, except for overbite. These findings might be helpful for clinicians in selecting the types of facemasks for growing Class III malocclusion patients.

Effect of orthodontic treatment with premolar extractions on occlusal planes: A retrospective study.

To figure out whether premolar extractions treatment would influence the cant of the occlusal planes and thus affect dentoskeletal patterns in patients with different types of malocclusions. A total of 140 post-orthodontic treatment subjects (96 females, 44 males) were included in this study, and their lateral cephalograms and demographic information were collected and analysed. The patients were divided into extraction and non-extraction groups. The ANB, SNA, SNB, Wits, Facial Height Index (FHI), SN-MP, SN-AOP, SN-POP and AOP-POP angle were measured on the cephalograms. Other possible confounding factors were recorded. Data were analysed by univariate analysis, stratified analysis, multivariate analysis, and coefficient analysis. After treatment, the changes in the AOP-SN, POP-SN and AOP-POP angle were statistically different between the extraction and non-extraction groups. The results were consistent in different skeletal malocclusions and extent of crowding according to stratified analysis. After adjusting all confounding factors, the cant of the posterior occlusal plane was flattened further by 2.14 degrees in the extraction group than the non-extraction group after orthodontic treatment, and the AOP-SN and AOP-POP angle would further increase by 1.72 and 3.81 degrees, respectively. Although no significant differences were found between the two groups, the SNA, ANB, and Wits in the extraction group decreased more with increased counterclockwise rotation of the mandible. Compared to the non-extraction group, there were more increases in the AOP-SN and AOP-POP angle and more posterior flattening in patients with four premolar extractions despite different types of dentoskeletal malocclusion, which were correlated to the change of variables in sagittal and vertical dimensions such as Wits and FHI.

Is there variation in the depth of the curve of Spee in individuals with different dentoskeletal patterns? A systematic review with meta-analysis.

To systematically evaluate all the evidence assessing variations in the depth of the curve of Spee (COS) according to the presence/absence of different dentoskeletal characteristics. The eligibility criteria were outlined following the PECO framework, as follows: studies evaluating individuals with complete permanent dentition including second molars (P), which compared a group with a certain dentoskeletal variation (E) versus another group without the variation (C), regarding the depth of the COS (O). MEDLINE (via PubMed), Scopus, Web of Science, The Cochrane Library, LILACS and BBO (via Virtual Health Library), OpenGrey, and Google Scholar were searched up to September 2021 to identify eligible reports. Duplicates were removed from all the records retrieved. The selection process and data collection were performed independently by two review members. The risk of bias was also assessed independently and in duplicate, using the guideline described by Fowkes and Fulton. Several meta-analyses (α = 0.05) were conducted to estimate the mean differences (MD) or standardized mean differences (SMD) in the depth of COS between individuals presenting or not certain dentoskeletal characteristics. The certainty of evidence was assessed using the GRADE tool. Thirty-five studies were selected for qualitative synthesis, and 29 of them for quantitative synthesis. All studies had methodological limitations that affected the risk of bias and increased the likelihood that results were due to chance. Syntheses showed that Class II malocclusion (SMD = 0.87; 95% CI: 0.61, 1.13; P &lt; 0.00001; six datasets including 260 subjects analysed), Class II division 1 (SMD = 1.09; 95% CI: 0.62, 1.56; P &lt; 0.00001; 14 datasets including 823 subjects analysed) and Class II division 2 (SMD = 2.65; 95% CI: 1.51, 3.79; P &lt; 0.00001; eight datasets including 476 subjects analysed) had deeper COS than Class I malocclusion. The skeletal Class II also presented higher COS values than skeletal Class I (SMD = 0.57; 95% CI: 0.02, 1.12; P = 0.04; four datasets including 299 subjects analysed). Individuals with Class III malocclusion had flatter COS than the subjects having Class I malocclusion (SMD = -0.57; 95% CI: -1.07, -0.08; P = 0.02; nine datasets including 505 individuals analysed). No difference was shown in the COS depth between skeletal Class III and Class I (P &gt; 0.05). Deep bite individuals had higher COS depth than those with normal overbite (MD = 0.61; 95% CI: 0.41, 0.82; P &lt; 0.00001; two datasets including 250 subjects analysed). In addition, hypodivergent individuals presented deeper COS than normodivergents (SMD = 0.62; 95% CI: 0.37, 0.86; P &lt; 0.00001; six datasets including 305 subjects analysed), and there was no significant difference in the COS depth between hyperdivergent and normodivergent individuals (P = 0.66). The certainty of evidence was rated as very low for all the syntheses. All the quantitative syntheses included results from studies with methodological flaws. Therefore, they are potentially biased. Moreover, the evidence was also mainly affected in terms of the inconsistency of the results and the imprecision of the estimates. Although an apparent influence of dentoskeletal Class II, Class III malocclusion, deep bite, and the hypodivergent skeletal pattern on the depth of the COS is suggested, it is not possible to make definitive conclusions on the matter due to the very low certainty of the evidence. Further high-quality research is necessary.

Evaluation of tongue posture &amp; dimensions in relation to skeletal Class I and Class II patterns- A cephalometric study

Association of tongue posture with dental and facial skeletal pattern have been suggested in past. This study was undertaken to assess tongue posture and dimensions in Class I and Class II Dentoskeletal patterns to determine whether any correlation exists between tongue posture and skeletal pattern of an individual. Cephalograms of 150 individuals (aged 18-23 years), taken in Natural Head Position (NHP) and tongue at rest were divided into three groups i.e. Group 1 – Class I Normal occlusion, Group 2 – Class II Division 1 Normodivergent and Group 3 – Class II Division 1 Hypodivergent, consisting of 50 samples each. To ensure the rest position of tongue, patient was asked to relax for 30 seconds after coating the tongue with barium sulphate in midline and then to swallow, and the X-ray was taken at the end of swallowing. Each group was divided into two subgroups according to sex. Groups were constituted according to the Frankfort mandibular plane angle (FMA) angle. The subjects who had skeletal Class II pattern due to mandibular retrusion and not due to maxillary prognathism were only included in the study group. Statistical analysis was done using the software SPSS version 21.0. The statistical tests used were unpaired t-test and One-way ANOVA test with post-hoc bonferroni test. The p-value was considered significant if less than 0.05.The dorsum of the tongue was higher at back and lower in front in Class II Division 1 Hypodivergent group as compared to Class I Normal occlusion group (P&amp;#60;.05). Tongue height and tongue length were significantly reduced in Class II Division 1 Normodivergent and Class II Division 1 Hypodivergent malocclusion groups when compared to Class I control group (P&amp;#60;.05).The study supports the existence of a relationship between posture &amp; dimensions of the tongue with Class I and Class II skeletal patterns.

The influence of antero-posterior dentoskeletal pattern on the value of nasal soft tissue angles: a cephalometric study.

The aim of this study was to examine the influence of sagittal dentoskeletal pattern on the value of profile nasal soft tissue angles and estimate the significance of examined differences for each angle. Lateral cephalograms were used to examine the nasofrontal angle, nasofacial angle, nasal tip angle, and nasolabial angle of 120 adult Caucasian subjects (60 male and 60 female) from the central Balkan area. Subjects were divided into four groups according to the ANB angle and incisors inclination: class I as the control group, class II division 1, class II division 2 and class III. By evaluating the influence of sagittal dentoskeletal relationships on the values of examined angles, significant differences were found among subjects with class I and class II/2 (p = 0.028), so as class III (p = 0.002) for nasal tip angle. The nasofacial angle was found to differ among subjects with class I and class II/1 (p = 0.002), so as class III (p = 0.001). Different dentoskeletal patterns have significant influence on values of the nasal tip angle and nasofacial angle, and don't have influence on the values of the nasofrontal and nasolabial angle.

Three-Dimensional Evaluation of the Tongue Volume in Different Dentoskeletal Patterns - A Cone Beam Computed Tomographic Study.

Aim:The aim of this study is to evaluate tongue volume using cone-beam computed tomographic (CBCT) and its correlation to different growth patterns in patients.Materials and Methods:Sixty preorthodontic records of CBCT scans of subjects ranging from 14 to 25 age group from retrospective data of department were selected for the study. Patients were classified into three groups based on angle FMA; Group I (n = 20) with average growth pattern (FMA 22°–28°); Group II (n = 20) vertical growth pattern (FMA >28°); Group III (n = 25) horizontal growth pattern (FMA <20°). Tongue volume evaluation was done using Myrian® Software. Dentoskeletal features and parameters related to archform such as palatal vault depth, interpremolar, and intermolar distance were evaluated in all the subjects. ANOVA test was used for intergroup comparison of tongue volume and dentoskeletal parameters in all three groups. Correlation of the tongue volume to dentoskeletal parameters was done using Pearson's correlation test.Results:Mean tongue volume in Group I was 66.10 cm3, Group II, 66.04 cm3 and Group III was 66.72 cm3. There was a statistically significant correlation (P < 0.5) of tongue volume with palatal vault width, maxillary length, and mandibular interpremolar and intermolar distance among dentoskeletal parameters.Conclusion:Tongue volume was found equal in all groups despite the variation in growth patterns. Skeletal differences leading to different growth patterns were found to be related to mandibular morphology. The results indicate the indirect role of the tongue in causing malocclusion in orthodontic patients.

Relationship of Nasal Morphology With Different Dentoskeletal Patterns: A Systematic Review

Introduction: The nose is considered by some clinicians as the keystone of facial aesthetics. A treatment plan can be customized to intensify the facial aesthetics of a patient through careful evaluation of the soft tissue drape. Hence, for getting a better outcome of the treatment plan, orthodontists are supposed to have in-depth knowledge and awareness of soft tissue changes, taking into notice the ethnic and racial variation in discrete cohorts. The objective of this study is to enlist the relationship of nasal morphology with different dentoskeletal (sagittal and vertical) patterns. Materials and Methods: A comprehensive electronic database search was performed till July 2020, of Cochrane Library, Embase, PubMed, Scopus, Google Scholar, Web of Science, Wiley Online Library, and ScienceDirect. Only articles published in the English language were included. After excluding all the irrelevant data through careful screening, a total of 15 articles were selected which discussed the nose–dentoskeletal pattern relation. Results and Conclusion: The nose is found to be convex in skeletal class II, straight in class I, and concave in class III. Those with increased vertical growth may have an increased tendency of a convex nasal dorsum. Maxillary and mandibular jaw length affect the nasal parameters more than the jaw position. Nasal length and nasal depth increase with the jaw length and mandibular and maxillary/palatal-plane inclination to the cranium. A long nose with increased nasal depth is expected in long faces and those with long upper and lower jaws. An upturned nose is found with an anticlockwise-rotated maxilla.

Comparison Between Treacher Collins Syndrome and Pierre Robin Sequence: A Cephalometric Study.

The aim of this study was to compare the dentoskeletal pattern of Treacher Collins syndrome (TCS) and nonsyndromic Pierre Robin sequence (PRS). Retrospective. Single center. Eighteen patients diagnosed with TCS (Group TCS) or PRS (Group PRS) in rehabilitation treatment at a single center. Group TCS was composed of 9 patients (4 male, 5 female) with a mean age of 12.9 years (standard deviation = 4.8). Group PRS was composed of 9 patients paired by age and sex with group TCS. Cone beam computed tomography-derived cephalometric images taken before the orthodontic or the orthodontic-surgical treatment were analyzed using Dolphin Imaging (Dolphin Imaging 11.0 & Management Solutions). Variables evaluating the cranial base, the maxillary and mandibular skeletal components, maxillomandibular relationship, the vertical components and the dentoalveolar region were measured. Intergroup comparisons were performed using t tests. The significance level considered was 5%. Intergroup differences in the mandible size and growth pattern were observed. Group TCS showed a smaller mandibular length (Co-Go, Co-Gn) and a higher palatal plane (SN-Palatal Plane) and mandibular plane angles (SN-Go.Gn) compared to group PRS. No differences between TCS and PRS were observed for the sagittal position of the maxilla, maxillomandibular relationship, and dental components. Treacher Collins syndrome presented a decreased mandible and a more severe vertical growth pattern compared to PRS.

THE INFLUENCE OF THE SAGITTAL DENTOSKELETAL PATTERN ON THE VALUE OF THE SOFT TISSUE PROFILE ANGLES - A CEPHALOMETRIC STUDY

The aim of this study has been to establish the values of soft tissue profile angles in subjects with dentoskeletal Class I, Class II Division 1, Class II Division 2, and Class III pattern, in order to examine the influence of sagittal dentoskeletal relation on the value of angular profile parameters. This comparative cephalometric study included the examination and the analysis by lateral cephalograms to evaluate soft tissue profile angles for 120 adult Caucasian subjects (60 women and 60 men) from the mid Balkan region divided into four groups towards ANB angle and incisors inclination. The following angles were examined: angle of facial convexity, facial convexity angle for the lower face and the angle of total facial convexity. By investigating the influence of the sagittal dentoskeletal pattern on the value of facial convexity angles, significant differences have been established between subjects with Class I and Class II Division 1 and 2 for all examined angles (p&lt;0.001; p=0.011), while the differences between Class I and Class III are only significant for the facial convexity angle and facial convexity angle for the lower face, while the differences in the overall facial convexity angle are not significant (p=0.067). There are significant differences between subjects for all examined angles except the total facial convexity angle between Class I and Class III.

Letters From Our Readers.

To: Editor, The Angle OrthodontistRe: Orthodontic treatment stability predictors: A retrospective longitudinal study. The Angle Orthodontist. 2016. Online EarlyI would like to congratulate the authors on publishing this interesting paper. It examined some of the factors related to stability of orthodontic treatment. I have two questions for the authors:1. The study showed an association between history of extractions and lack of midline stability. Using the space provided by extractions could be one of the effective methods to correct midline deviation. Sometimes we even perform asymmetric extraction to shift midline position. Since no details of the extractions or specific differences between the extraction and non-extraction cases were provided, can you provide insight into whether the extraction cases exhibited a higher incidence and/or greater severity of midline deviation before orthodontic treatment? Or perhaps extraction cases showed more improvement of midline position than the non-extraction cases? If this is true then do you think it might explain the negative association between extractions and midline stability?2. Different types of tooth movements may be needed or associated with the treatment of different dentoskeletal patterns or malocclusions. For example, mandibular incisors are often proclined during Class II treatment, and this could be unstable. However, the association between dentoskeletal patterns and treatment stability is not conclusive. The paper stated that ‘Angle Classification' of the subjects was extracted from the clinical history but results concerning Angle classification were not reported in the Results and Discussion sections. Can you share any specific information regarding the association between pretreatment Angle classification and stability in your study?Thank you for conducting this important investigation that raises interesting questions to discuss.

Cervical vertebrae staging in pre-orthodontic patients in Benin City, Nigeria

Objective: To determine the prevalence of the various stages of skeletal maturation of the cervical vertebrae in pre-orthodontic patients in Benin City, Nigeria.Method: The first six cervical vertebrae of 105 untreated orthodontic patients attending the clinic of the University of Benin Teaching Hospital were assessed on the cephalometric radiograph to determine the stages of maturation. Correlations between age, gender, type of malocclusion and skeletal maturation stages were determined using the software SPSS (version 16). Significant values of P&lt;0.05 were applied were applicable.Result: The average age of participants was 14±1.5 years with an almost equal gender distribution. Cervical vertebrae maturation (CVM) stage 3 was the most frequently occurring with 26.7% of the sample population. This was also seen mostly in the 11-yearold age group. The least frequently reported was CVM stage 1 with 5.7%. According to dento-skeletal patterns, CVM stage 3 was most prevalent in bimaxillary proclination with (29.3%). Others include mandibular retrusion, maxillary protrusion and skeletal 2 with 26.3%, 25% and 17.2% espectively. Males showed a higher distribution in the CVM stage 3 than females. There was also a significant association between age and Cervical maturation, P&lt;0.05.Conclusion: Cervical Maturation stages 1-6 were identified in pre-orthodontic patients aged 7-21-years. Stage 3 was the most frequently occurring.CVM stage and is seen more in 11-year-old-males. Females demonstrated a higher number in CVM stages 4 and 5. The correlation coefficient between age and CVM was 0.86 (P&lt;0.05) for stage 3. &#x0D;

Phenotypic diversity in white adults with moderate to severe Class III malocclusion

Class III malocclusion is characterized by a composite of dentoskeletal patterns that lead to the forward positioning of the mandibular teeth in relation to the maxillary teeth and a concave profile. Environmental and genetic factors are associated with this condition, which affects 1% of the population in the United States and imposes significant esthetic and functional burdens on affected persons. The purpose of this study was to capture the phenotypic variation in a large sample of white adults with Class III malocclusion using multivariate reduction methods. Sixty-three lateral cephalometric variables were measured from the pretreatment records of 292 white subjects with Class II malocclusion (126 male, 166 female; ages, 16-57 years). Principal component analysis and cluster analysis were used to capture the phenotypic variation and identify the most homogeneous groups of subjects to reduce genetic heterogeneity. Principal component analysis resulted in 6 principal components that accounted for 81.2% of the variation. The first 3 components represented variation in mandibular horizontal and vertical positions, maxillary horizontal position, and mandibular incisor angulation. The cluster model identified 5 distinct subphenotypes of Class III malocclusion. A spectrum of phenotypic definitions was obtained replicating results of previous studies and supporting the validity of these phenotypic measures in future research of the genetic and environmental etiologies of Class III malocclusion.

“Safe Zones” for miniscrew implant placement in different dentoskeletal patterns

To assess the influence of different dentoskeletal patterns on the availability of interradicular spaces and to determine the safe zones for miniscrew implant placement. Periapical radiographs of 60 subjects with skeletal Class I, II, or III patterns were examined. For each interradicular site, the areas and distances at 3, 5, 7, 9, and 11 mm from the alveolar crest were measured. In the maxilla, the greatest interradicular space was between the second premolar and the first molar. In the mandible, the greatest interradicular space was between the first and second molars, followed by the first and second premolars. Significant differences in interradicular spaces among the skeletal patterns were observed. Maxillary interradicular spaces, particularly between the first and second molars, in the subjects with skeletal Class II patterns, were greater than those in the subjects with skeletal Class III patterns. In contrast, in the mandible, interradicular spaces in the subjects with skeletal Class III patterns were greater than those in the subjects with skeletal Class II patterns. For all skeletal patterns, the safest zones were the spaces between the second premolar and the first molar in the maxilla, and between the first and second premolars and between the first and second molars in the mandible.

Lip Vermilion Profile Patterns and Corresponding Dentoskeletal Forms in Female Adults

To objectively classify shapes of the human lip vermilion in the lateral view, and to examine whether any morphologic characteristics of dentoskeletal patterns are specific to each classified lip profile pattern. Pretreatment, lateral facial photographs of 234 Japanese women were selected. Investigators with expert knowledge of the anatomic traits of the lip vermilion in the lateral view extracted from images of the face a 13-dimensional feature vector that represented lip vermilion profile shapes. The vector quantization technique was applied to the feature vectors to mathematically optimize the number of lip vermilion profile patterns. Dentoskeletal patterns that corresponded to each classified lip shape were compared statistically. Seven patterns were found, and differences between patterns were notably maximized by the flatness of the anterior portion of the lip vermilion for the upper and lower lip, the position of the most protruded point of the lip vermilion, lip fissure inclination, and differences between the horizontal positions of the upper and lower lip vermilions. The dentoskeletal forms showed significant differences between classified lip vermilion profile patterns (P < .01). (1) Vector quantization revealed that classifying lip vermilion profiles into seven representative patterns was optimal for maximizing differences in the configuration of the lip vermilion. (2) Lip vermilion profile shapes were found to be associated with horizontal lengths of the anterior cranial base, horizontal/vertical positions, inclination and length of the mandible, and horizontal positions and labio-lingual inclinations of the upper and lower incisors.

開こうを伴う骨格性下顎前突症患者の顎矯正手術後の硬軟組織変化‐上下顎移動術と下顎枝矢状分割術単独との比較‐

The purpose of this study was to evaluate hard and soft tissue changes in mandibular prognathic patients with open bite following different orthognathic surgery.Twenty adult patients who underwent orthognathic surgery to correct mandibular protrusion and open bite were selected for this study. The subjects were divided into the following two groups based on surgical method: 12 subjects who underwent mandibular setback osteotomy with the sagittal split technique (one jaw group) and 8 subjects who underwent mandibular setback osteotomy with the sagittal split technique and combination (Le fort I and horseshoe) osteotomy in bimaxillary surgery (two jaw group). A pair of pre- and post-operative lateral cephalograms was used for hard and soft tissue analysis. Statistical analysis using a paired t test was performed for comparative study.No significant differences were observed in the pre-operative anterior occlusion, dento-skeletal pattern and facial profile between the two groups. Anterior occlusion was improved in both groups following surgery and no significant differences were observed in the post-operative overjet and overbite between the two groups. However, significant differences were observed both in the dento-skeletal and facial profile changes between the two groups. The amount of mandibular up-backward movement, especially the chin portion in the two jaw group was significantly larger than that in the one jaw group due to the clockwise rotation of the maxillary occlusal plane following superior repositioning of the maxillary posterior portion. In accordance with this larger mandibular up-backward movement coupled with maxillary advancement in the two jaw group, more harmonized bimaxillary skeletal relationship as well as better facial profile were achieved in the two jaw group in comparison with that in the one jaw group. It is suggested that a combination of Le fort I and horseshoe osteotomy in bimaxillary surgery is a useful technique to treat mandibular prognathic patients with open bite.

Rotational effects of S-N on the dentoskeletal pattern within the range of normal.

The range of orientation of SN in relation to the craniofacial centroid line in a Class I sample with "acceptable" profiles is divided into three groups for comparison with facial dentoskeletal structures and evaluation of the adaptations among them. This manuscript was originally submitted September, 1986.

Skeletal morphologic features of anterior open bite

Lateral cephalograms of sixty patients with open bite and sixty untreated subjects who were determined clinically to have Class I normal occlusions were studied. The following six values were recorded: (1) ratio of posterior to anterior face height, (2) ratio of upper to lower face height, (3) Sn GoGn angle, (4) gonial angle, (5) SN-PP angle, and (6) PP-GoGn angle. Results were compared with previous studies. The constancy of the ratios and angles with age was tested and an attempt was made to separate the open-bite sample into skeletal and dentoalveolar groups. Results were generally consistent with those reported previously, except for the Sn PP angle, which was not significantly different from the normal group. In the open-bite sample the study showed a decrease in the ratio of PFHAFH, a decrease in the ratio of UFHLFH, and an increase in the other angles measured. Upon further division of the sample into mixed- and permanent-dentition groups, it was found that the angles and ratios remained relatively constant with age. An attempt to divide the open-bite sample into skeletal and dentoalveolar groups resulted in more extreme values for all the measurements made. The difficulty in differentiating between the two groups and the variability of dentoskeletal patterns in open bite is discussed.

The integumental profile

Modern orthodontics implies not only occlusal excellence, but also the positioning of teeth to produce optimal facial harmony for the individual patient. The soft-tissue veneer covering the teeth and bone varies so greatly that study of the dentoskeletal pattern may be inadequate in evaluating facial disharmony. A method of direct integumental analysis is presented, employing angular readings that describe profile components to the skull as a whole (inclination angles) and to each other (contour angles). These readings are made from oriented lateral headplates exposed to show both hard- and soft-tissue detail. The average morphology and variation of acceptable profiles are described, based on the Herron sample (a group of good faces picked by a panel of artists). The hypothesis is explored that average inclination, contour, and proportion is related to profile excellence. Graphic comparison to the Herron sample by use of the integumental profile grid expedites the analysis of malocclusion deformity and the study of soft-tissue changes occurring during growth and treatment.