Dolichofacial Type Research Articles

Proposal of a Protocol for Adjusting the Value of the SN-GoGn Angle in Steiner Cephalometry

Background: The objective of this study was to compare the facial pattern according to Steiner’s cephalometric analysis with other facial measurement methods (Ricketts, Björk-Jarabak, and McNamara). Methods: 200 patients from a university orthodontic clinic were studied. Measurements were taken using Ricketts, Steiner, Björk-Jarabak, and McNamara methods. Results were compared using standard deviation proportions. Results: Significant differences were found between Steiner’s method and the gold standard. No differences were observed between mixed and permanent dentition groups. Errors were noted in facial type classification: 54.8% in the brachyfacial group, 80% in the mesofacial group and 14.5% in the dolichofacial group. Conclusion: The mandibular angle of Steiner tends to make a diagnosis more towards the dolichofacial type compared to other methods. A protocol is proposed to adjust the value of the mandibular angle of Steiner to the other three methods in a Spanish population.

Bioelectrical activity in temporalis and masseter muscles across different gnathic types

Relevance. Discrepancies in the bioelectrical activity of the masseter muscle were observed through surface electromyography analysis. Despite the availability of scientific literature on the morphological and anatomical variances in the mastication muscles and subcutaneous adipose tissue across different gnathic types, these differences are often overlooked in the interpretation of surface electromyography absolute values.Materials and methods. A clinical evaluation, including the measurement of craniofacial parameters and an electromyography study of the right and left temporalis (RTA and LTA) and masseter muscles (RM and LM), was conducted on 73 individuals aged 21 to 24. Subjects were categorized based on upper and lower face gnathic type indices into three groups of 10: Group 1 (brachyfacial type), Group 2 (mesofacial type), and Group 3 (dolichofacial type). The study compared the surface electromyography-derived IMPACT index and average amplitude values of the muscles across groups, alongside analyzing the correlation between electromyographic values and gnathic type indices (GPDu.f./t-t and GPDl.f./ko-ko), with statistically significant differences noted at p ≤ 0.017.Results. Differences in RM and LM parameters, and the IMPACT index during the "Maximal Voluntary Gnathic Clenching of the Jaws" (MVC) test were statistically significant among the groups. An increase in both the IMPACT index and average masseter muscle values was noted in dolichofacial subjects. Significant variations in LM values during the MVC test were observed between dolichofacial and mesofacial subjects. In the MVC test, groups 1 and 3 demonstrated a moderately strong positive correlation between the IMPACT index and GPDu.f./t-t and GPDl.f./ko-ko, while a strong positive correlation was identified between the RM parameter and GPDu.f./t-t and GPDl.f./ko-ko.Conclusion. In the MVC test, the RM and LM parameters, as well as the average IMPACT index, were notably higher in dolichofacial subjects compared to other groups. A direct correlation between the mean right masseter bioelectrical activity and the average IMPACT index with the upper and lower facial gnathic indices was observed in brachyfacial and dolichofacial subjects in the MVC test.

Factors Associated with the Proximity of the Incisive Canal to the Maxillary Central Incisor

The position of the maxillary central incisors (MCIs) is an important factor in treatment planning since it is related to esthetics and physiological function. This study aimed to evaluate maxillofacial morphology related to the proximity of the MCI to the incisive canal (IC) using cone-beam computed tomography (CBCT). In 157 patients, the distance between the MCI and IC was measured using CBCT images, and the maxillofacial morphology was measured using cephalograms. The relationship between age, sex, and cephalometric analysis was subsequently investigated using stepwise multiple regression analysis, with the distance between the MCI root apex and IC as the objective variable, and age, sex, and cephalometric variables as explanatory variables. The results demonstrated significant associations between the distance separating point A and the pterygomaxillary fissure projected on the palatal plane (B = 0.092, p < 0.01), the maxillary central incisal edge to the Frankfort horizontal plane (B = −0.058, p < 0.01), and the mandibular plane (B = −0.036, p = 0.031). Age and sex showed no association with the distance between the IC and MCI. Particular attention should be paid to the proximity of the tooth root to the IC in patients with short anteroposterior diameters of the maxilla and an anterior labial tilt of the dolichofacial type.

Associations between skeletal discrepancies, breathing pattern, and upper airway obstruction in Class III malocclusions.

To verify the associations between sagittal and vertical skeletal discrepancies, changes in upper airways, and breathing pattern in children and adolescents with Angle Class III and Class III subdivision malocclusions. Eighty-five children and adolescents with a mean age of 9.5±1.74 years were selected. Cephalometry assessed the sagittal relationship (AO-BO measurement), facial types (Ricketts VERT index), nasopharynx, and oropharynx. An otorhinolaryngologist analyzed the breathing pattern and upper airway obstruction during anamnesis, physical examination, anterior rhinoscopy, and nasofibroscopy. Medical records were also reviewed. For statistical analysis, ordinary one-way ANOVA, Kruskal-Wallis (Tukey's post-hoc), unpaired t-test, Pearson's correlation, chi-square, and Fisher's exact tests (p<0.05) were used. The nasopharyngeal cephalometric dimension and pharyngeal tonsil hypertrophy were associated, whereas the oropharyngeal cephalometric dimension and palatine tonsils hypertrophy were not. Sagittal discrepancies were associated with septum deviation, while facial type was associated with inferior turbinate and palatine tonsils hypertrophy. However, facial type was not associated with breathing pattern, septum deviation, and pharyngeal tonsils hypertrophy. Sagittal discrepancies and type of malocclusion were not associated with breathing pattern and changes in upper airways, except for the severity of septum deviation and Class III malocclusions, which were associated with large sagittal discrepancies. Although the facial types analyzed presented signs of airway obstruction, the highest prevalence of inferior turbinate and palatine tonsils hypertrophy were found in patients with dolichofacial type.

The effect of mandibular flexure on the design of implant-supported fixed restorations of different facial types under two loading conditions by three-dimensional finite element analysis.

Objective: Investigating the biomechanical effects of mandibular flexure (MF) on the design of implant-supported fixed restorations in edentulous jaws of different facial types. Methods: Three-dimensional finite element models were established to analyze mandibular displacement and stress distribution of implant-supported fixed restorations (four or six implants, different implant numbers and sites, and the design of the superstructure across the dental arch in one or two or three pieces, under the loading conditions of maximum opening or right unilateral molar occlusion) in mandibular edentulous patients of three different facial types (brachyfacial, mesofacial, and dolichofacial types). Results: The brachyfacial type presented higher mandibular flexure and stress in the overall restorative system, followed by the mesofacial and dolichofacial types. During jaw opening and occlusal movements, the one-piece framework showed the lowest bone stress values surrounding the anterior implants and gradually increased to the distal position, and the three-piece framework showed the highest stress values for peri-implant bones. Also, the split framework could greatly increase the stress on abutments and frameworks. Moreover, fixed implant prostheses with cantilevers can generate high amounts of biomechanical stress and strain on implants and surrounding bones. The bone surrounding the anterior implant increased in stress values as the most distal implants were more distally located regardless of frameworks. The zirconia framework demonstrated higher stresses than the titanium framework. Conclusion: The design of edentulous fixed implant-supported restorations can be optimized for facial types. For patients of the brachyfacial type or with high masticatory muscle strength, the non-segmented framework without a cantilever provides an optimal biomechanical environment.

EVALUATION OF THE FACIAL PATTERN AND ORAL FUNCTIONS IN CHILD PATIENTS WITH MICROCEPHALY

<h3>Objectives</h3> The study aimed to evaluate the correlation of facial pattern and oral functions in children with microcephaly. <h3>Study Design</h3> The population consisted of 7 children with complete primary dentition. Data collection consisted of the analysis of clinical records and front and profile facial photography. <h3>Results</h3> There was a predominance of dolichofacial type (100%) and vertical pattern (85.71%). All had unilateral chewing, mouth breathing, bruxism, and atypical swallowing. The proportion of severe microcephaly (-3DP) was higher in males (<i>P</i> = .04). There was no association between the severity of microcephaly and facial type (<i>P</i> > .05), although the vertical pattern predominated in severe microcephaly (100%). There was a moderate association between the dolichofacial type and the presence of orofunctional disorders (<i>P</i> < .05). <h3>Conclusions</h3> Oral health care for these children should include dental development, the stomatognathic system, and craniofacial growth in early childhood to significantly reduce curative procedures.

Клінічно-сонографічний аналіз біометричних показників товщини щоки та жирового тіла щоки у пацієнтів з різним типом обличчя

The purpose of the study was to conduct a scientific and practical analysis of clinical sonographic results of examination of patients with different face types in the process of planning the reconstruction of facial soft tissues with the involvement of buccal fat pad. Materials and methods. The study was conducted on 28 patients of different age groups (from 20 to 45 years old) with defects and deformities of the tissues of the dental system. Instrumental sonographic analysis of the thickness of the buccal fat body was performed using an ultrasound scanner GE Logiq E (USA), transducer frequency 7.5-12 MHz. The types of buccal fat pad of correct (oval) or irregular (“hourglass”) shapes were determined, as well as its localization in relation to the median axial location of the crown of the first upper molars and the average value of the buccal fat pad thickness with an accuracy of 0.01 mm. Results and discussion. The results of a clinical study of the average value of the thickness of the cheek of patients with mesofacial type of face allowed to establish that on the left its value is 8.94±0.89 mm, on the right side – 9.05±0.82 mm. In patients with brachyfacial type of face on the left the value of the thickness of the cheek is 12.33±1.63 mm, and on the right side – 12.44±1.54 mm. In patients with dolichofacial type of face on the left, the index of the thickness of the cheek reaches the value of 7.53±0.61 mm, on the right side – 8.58±1.093 mm. Statistical significance was determined in comparison with data from the group of patients with mesofacial facial type. The obtained statistical results show mediocre values of buccal fat pad thickness in patients with mesofacial type of face, which are 1.117 times larger than in dolichofacials and 0.73 times smaller than in brachyfacials, which should be taken into account when conducting sonographic studies. Differences in the quantitative values of buccal fat pad thickness, which are established by clinical and sonographic studies conducted in patients with different types of faces is recommended to take into account when choosing surgical approaches during surgical closure of tissue defects of the alveolar processes of the jaws with autologous buccal fat pad. Conclusion. Buccal fat pad has morphological advantages associated with its saturation with cell complexes that have significant degree of vascularization, pliable texture, plasticity and direct participation in the implementation of the basic functions of the maxillofacial area

Perceptions of orthodontists, laypersons, and patients regarding buccal corridors and facial types

The space on each side of the mouth, between the commissure of the mouth and the buccal surface of the last visible tooth, is called the buccal corridor. The size of the buccal corridor can affect perceptions of facial esthetics. We analyzed the perceptions of orthodontists, laypersons, and orthodontic patients regarding the size of buccal corridors in people with brachyfacial, mesofacial, and dolichofacial types. Photographs of 1 male and 1 female model were modified digitally into brachyfacial, mesofacial, and dolichofacial types. Each facial type was further modified to create 5 sizes of buccal corridors. Orthodontists, adult orthodontic patients, and laypersons were invited to rate the photographs. Orthodontists rated lower than the other groups of raters when they evaluated the female model with the buccal corridors of 20% (P<0.05). Laypersons could not distinguish the changes of the buccal corridors when evaluating the male model with brachyfacial and mesofacial (P>0.05). Orthodontic patients rated significantly higher than the orthodontists and the laypersons when evaluating the dolichofacial type of both models (P<0.05). Orthodontists are more sensitive to the buccal corridors than are orthodontic patients and laypersons. It is only necessary to consider eliminating the patient's buccal corridors when the buccal corridor area ratio is over 15%.

Distribution of Pediatric Malocclusion Patients in Seoul National University Dental Hospital

A total of 580 patients, who visited and received an orthodontic diagnosis in the Department of Pediatric Dentistry, Seoul National University Dental Hospital from 2017 to 2019, were investigated in this study. The aim of this study was to evaluate skeletal patterns of pediatric orthodontic patients determined with lateral cephalometric analysis and to analyze the relationship between skeletal pattern and probable associated clinical features. Also, the modality of orthodontic treatment for each skeletal classification was investigated to aid in therapeutic decisions.&lt;br/&gt;Patients aged 7 year accounted for the largest age group; 54.2% of patients showed a skeletal class I pattern, 22.2% showed a skeletal class II pattern, and 23.6% showed a skeletal class III pattern. Bi-maxillary retrusion for skeletal class I, retruded mandible with normal positioning of the maxilla for skeletal class II, and retrusion of the maxilla with protrusion of the mandible for skeletal class III were the largest subgroups by skeletal pattern. Brachyfacial type accounted for 55.0% of patients, followed by 31.9% of mesofacial type and 13.1% of dolichofacial type. The prevalence of anterior crossbite in the study was 43.3%, higher than that in previous studies.

Association between the Anatomy of the Mandibular Canal and Facial Types: A Cone-Beam Computed Tomography Analysis.

We evaluated the anatomical variations of the mandibular canal associated with various facial types, age, sex, and side of the face studied. We analyzed 348 hemimandibles in subjects without a history of trauma, lesions in the lower arch, or orthognathic or repair surgery in the posterior mandible. Facial type was determined using the VERT index. The canal path was classified as Type 1 (a large, single structure passing very close to the root tips); Type 2 (a canal passing closest to the mandibular base); and Type 3 (a canal present in the posterior mandibular region, with a lower canal running through the mandibular branch, reaching the anterior region). Bifid canals (type 3) were classified into four categories according to the course and number of mandibular canals. The brachyfacial and mesofacial types presented a Type 1 canal in 95.5% (n=166) of subjects, in dolichofacial types, 68.2% (n=45) presented a Type 2 canal, while in the mesofacial type, a lower prevalence of the bifid mandibular canal was observed (13.0%, n=23) than in the other facial types. The bifid canal showed significant association with facial type only (p < 0.05), but no significant association was observed with the anterior loop type (p > 0.05). Facial type is significantly associated with the path and morphological variations of the mandibular canal, independently of the side of the face studied, age, and sex.

Position of Impacted Mandibular Third Molar in different Skeletal Facial Types

Introduction: Variation in growth pattern in different facial forms affect the space available for tooth eruption, therefore the mandibular third molar impaction has correlation with different skeletal facial types.Objective: To determine the position of impacted mandibular third molar in different skeletal facial types in Nepalese samples.Materials &amp; Method: This cross sectional study was carried out on pre-treatment lateral cephalogram and orthopantomogram records of 207 orthodontic patients visiting Kantipur Dental College and Hospital. Age range of the sample was 16-33 years. Various facial forms were determined with the help of mandibular plane angle (SN-GoGn); for which Nemoceph software was used. Beta angle was used to determine the angle of impaction of mandibular third molar. Impaction pattern was classified as per Pell &amp; Gregory and Winter’s system. SPSS version 20 was used for statistical analysis.Result: Overall rate of mandibular third molar impaction was 63.77% (11.11% unilateral and 52.66% bilateral impaction). The most common type of impaction bilaterally was mesioangular based on Winter’s classification, Class II Position B based on Pell &amp; Gregory’s classification. Higher rate of mandibular third molar impaction was found in dolichofacial type of face (49.2%).Conclusion: Decreased mandibular third molar impactions are seen in brachyfacial type compared to mesofacial and dolichofacial types

Comparison of clinical and electromyographic rest vertical dimensions in dolichofacial and brachyfacial young adults: A cross-sectional study

Statement of problemTherapeutic procedures that increase occlusal vertical dimension (OVD) may have different responses in patients with different craniofacial vertical patterns. The effect on these patients of increasing their OVD is not well understood. PurposeThe purpose of this clinical study was to compare measurements of vertical jaw separation (VJS) in patients with brachyfacial and dolichofacial craniofacial patterns in 2 vertical dimensions: the clinical rest/postural vertical dimension (CR/PVD) and electromyographic rest vertical dimension (EMGRVD). Material and methodsSixty healthy dental students were selected at random after a lateral skull radiograph was made. The Ricketts (VERT index) analysis was used to determine 30 brachyfacial (G1) and 30 dolichofacial (G2) types. The VJS was measured for G1 and G2 types in the 2 rest vertical dimensions specified. CR/PVD was recorded using 2 methods: swallowing (CR/PVD-P1) and the phonetic breathing method (CR/PVD-P2). The Shapiro-Wilk test was used for data distribution, and the Mann-Whitney U test was used to accept or reject the null hypothesis (α=.05). ResultsMean VJS in CR/PVD-P1 was 1.92 ±1.14 mm for the brachyfacial and 1.36 ±0.58 mm for the dolichofacial facial group (P=.05). The mean VJS in CR/PVD-P2 was 1.89 ±1.17 mm for the brachyfacial and 1.31 ±0.58 mm for the dolichofacial group (P=.03). The mean VJS in EMGRVD was 8.23 ±2.21 mm for the brachyfacial and 16.55 ±4.29 mm the dolichofacial group (P<.001). ConclusionsCR/PVD measurements in dolichofacial individuals were lower than those in brachyfacial individuals. EMGRVD measurements were higher in dolichofacial individuals than those in brachyfacial individuals. Biomechanical, physiological, and behavioral reasons might explain such diversity.

Effects of gum chewing exercise on maximum bite force according to facial morphology.

Development of the masticatory system is influenced by functional needs. Furthermore, masticatory exercise can improve masticatory function. The aim of this study was to evaluate the potential effect of the gum chewing exercise on the maximum bite force (MBF) in adult subjects with different facial morphologies. MBF was measured by a portable occlusal force gauge and lateral cephalogram was used for evaluation of craniofacial morphology in 19 individuals (7 males and 12 females) with a mean age of 25.4 years (SD ± 4.3). The volunteers underwent gum chewing exercise for 5 min twice a day for 4 weeks. MBF was measured before (T1) and after the 4‐week exercise (T2). The facial morphology of the subjects was classified into the brachy (n = 7), mesio (n = 7), and dolicho (n = 5) facial types. In all three groups, exercise was associated with a significant increase in MBF, though the percent increase was highest in the dolicho facial type. We conclude that gum chewing exercise can improve masticatory performance, especially in individuals with dolicho facial morphology.

Treatment of Class II malocclusion with mandibular skeletal anchorage

The aim of this case report was to present the dentofacial changes obtained with bone anchorage in a Class II patient with moderate to severe crowding. A boy, aged 14.5years, with a dolichofacial type, convex profile, and skeletal and dental Class II relationships was examined. After evaluation, functional treatment with bone anchorage and 4 first premolar extractions was decided as the treatment approach. Miniplates were placed on the buccal shelves of the mandibular third molars. The hook of theanchor was revealed from the first molar level. After surgery, the 4 first premolars were extracted to retract the protrusive mandibular incisors. The maxillary and mandibular first molars were banded, and a lip bumper was inserted to apply elastics and to help distalize the maxillary first molars. Orthodontic forces of 300 to 500g were applied immediately after placement, originating from the miniscrews to the hooks of the appliance to advance the mandible. After 20months of treatment, the patient had a dental and skeletal Class I relationship, the mandible was advanced, the maxilla was restrained, and overjet was decreased. The combination of a bone anchor, Class II elastics, and an inner bow is a promising alternative to functional treatment, along with extractions, in Class II patients.

Characteristics of Orthodontic Patients in Department of Pediatric Dentistry, Chonnam National University Dental Hospital

Interest in orthodontic treatment has increased. Consequently, the percentage of the orthodontic treatment in pediatric dentistry has also increased. Given this background, the purpose of this study was to analyze the characteristics and the trends of pediatric orthodontic patients of Chonnam National University Dental hospital. A total of 670 patients (349 male, 321 female) diagnosed with orthodontic problems during the period from January 1st, 2004 to December 31st, 2014, were analyzed. The number of pediatric orthodontic patients was high in January, February, July and August. When it comes to age, the percentage of the patients who were eighty-years old accounted for the largest age group with 19.6%, followed by seven-year, nine-year, ten-year, eleven-year, and six-year old age groups. Skeletal class 1 accounted for 48.1% of the total cases, followed by class 2 (28.7%) and class 3 (23.3%). Mesofacial type accounted for 65% of the total cases, followed by dolichofacial type (19.3%) and brachyfacial type (15.8%). The period of the first phase orthodontic treatment was steadily shortened from 30.4 months in 2004 to 11.5 months in 2013. The result of this study is expected to provide information of the pediatric orthodontic patients.

Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types.

ObjectiveEvaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals.Material and MethodsThe image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%). To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA). The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%.ResultsBrachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators.ConclusionTo achieve an enhanced esthetic smile it is necessary to observe the patient's facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive.

Changes in facial profile after maxillomandibular advancement surgery for obstructive sleep apnea syndrome

The aim of this study was to assess changes in the profile of adult male patients treated for obstructive sleep apnea syndrome (OSAS) with maxillomandibular advancement (MMA) surgery and to measure patient perception of changes compared with that of different panels. Fifteen consecutive apneic patients displaying a wide variety of morphological types, mean age 42 years (20-59), a BMI of 26.60 kg/m(2) (22-29), a mean initial Apnea Hypopnea Index (AHI) of 50.9 (19-85), underwent MMA. Assessment was done by facial photography, lateral cephalographs (Tweed analysis modified by Riley and Delaire architectural analysis), polysomnographic records and a validated self-assessment questionnaire. Patients' pre- and postoperative profiles were taken from photographs using Photoshop 7™ software. Their darkened outlines were shown randomly in positions A or B (pre- and postoperative) to panels composed of orthodontists (n=40), fine arts students (n=50) and lay persons (n=50) who were requested to choose the most attractive profiles. The MMA success rate for OSAS was 80% (12/15) for an AHI less than 15, with no surgical complications. All patients reported a reduction of their symptoms and 14 out of 15 were satisfied with the esthetic outcome. Mean advancement was 8.4mm (3.0-10.0) for the maxilla and 10.8mm (10.0-13.0) for the mandible. Following MMA, 12 out of 15 exhibited maxillary protrusion and six out of 15 mandibular protrusion. The mean change in the nasolabial angle was -5.7° (-27°; 14°). The postoperative profiles were preferred by 85% of the combined panels (P=<0.001), showing no significant difference from one panel to another. No skeletal characteristic could be correlated with the esthetic preference. Upper lip retrusion, open nasolabial angle and dolichofacial type emerged as positive preoperative predictors of esthetic preference. The profile changes following MMA were favorably perceived in the majority of cases. However, specific orthodontic preparation could be offered to patients with pronounced preoperative protrusion.

Median mandibular flexure at different mouth opening and its relation to different facial types: A prospective clinical study

Objective:To measure the arch width and Median mandibular flexure (MMF) values at relative rest and maximum jaw opening in young adults with Dolichofacial, Mesofacial, and Brachyfacial types and tested whether the variation in the facial pattern is related to the MMF values in South Indian population.Materials and Methods:This Prospective clinical study consisted of sample of 60 young adults. The subjects were grouped into 3 groups: Group 1: Brachyfacial, Group 2: Mesofacial and types, Group 3: Dolichofacial. Impressions were taken for all the 60 subjects and the casts were scanned and digitized. The intermolar width was measured for Dolichofacial, Mesofacial, and Brachyfacial subjects at relative rest (R) and maximum opening (O).Results:The statistical analysis of the observations included Descriptive and Inferential statistics. The statistical analysis was executed by means of Sigma graph pad prism software, USA Version-4. Kruskal wallis (ANOVA) followed by Dunns post hoc test was performed. Mann Whitney U-test was performed to assess the difference in MMF values between Males and Females of the three groups. The Mean (SD) Mandibular flexure in individuals with Brachyfacial type was 1.12 (0.09), Mesofacial type was 0.69 (0.21), and Dolichofacial type was 0.39 (0.08).Conclusions:The Mean intermolar width was maximum in Brachyfacial type and minimum in Dolichofacial type. MMF was maximum at the maximum mouth opening position and was maximum in individuals with Brachyfacial type.

Proposta para determinação do tipo facial a partir da antropometria

To describe orofacial indexes and proportions in adults, according to facial type and gender, and to verify the possibility to establish a way of classifying face based on anthropometry. Participants were 105 leukoderm adults, 34 male (32.4%) and 71 female (67.6%), with ages between 20 and 40 years old, patients in a private orthodontic clinic in Belo Horizonte, Minas Gerais, Brazil. The findings from the cephalometric analysis contained in their orthodontic records were used for determination of facial type. Subjects were divided according to gender and facial type, and were submitted to anthropometric facial measures obtained directly through a caliper rule. These measures were compared to six variables: facial index, lower face index, upper face index, chin-face height proportion, chin height proportion, and mandibular height proportion. The average values obtained by the subjects divided into genders and facial types that presented significant differences were: facial index, lower face index, upper face index, and mandibular height proportion for males, and mandibular height proportion, for females. To predict facial types, the following parameters were considered significant: facial index, upper face index and mandibular height proportion for the dolichofacial type, for males; and mandibular height proportion for the dolichofacial and lower face index for the brachyfacial type, for females. Some indexes and orofacial proportions present variations according to facial types and genders. In general, the anthropometric variables in this study are not good predictors to determine facial types.

Evaluation of upper airway obstruction in Class II children with fluid-mechanical simulation

The purpose of this study was to test the null hypothesis that dolichofacial and brachyfacial children with Class II malocclusion do not differ in upper airway obstruction. Furthermore, the ability of fluid-mechanical simulation to detect airway obstruction within the limitations of simulation was examined. Forty subjects from 7 to 11 years of age with Class II malocclusion participated and were divided into 2 groups, dolichofacial and brachyfacial, based on their Frankfort mandibular plane angles. Cone-beam computed tomography images supplied the shape of the entire airway. Two measures of respiratory function, air velocity and pressure, were simulated by using 3-dimensional images of the airway. The images and simulations were compared between the 2 facial types. The size of the upper airway did not differ statistically between facial types; however, the simulated maximal pressure and velocity of the dolichofacial type were significantly higher than those of the brachyfacial type. Airway obstruction differs with the Frankfort mandibular plane angle, even though the depth and cross-sectional area of the airway do not. The fluid-mechanical simulation system developed in this study detected differences in airway obstruction that were not apparent from morphologic studies.