Facial Height Research Articles

Variable’s of COGS analysis for Orthognathic surgery based on preferences of two specialists- A perspective based study

: Cephalometric analysis for Ortho-Gnathic Surgery (COGS) is the most commonly used analysis for diagnosing and treatment planning of an orthognathic case. This analysis consists of 37 parameters under 7 subheading which covers cranial, skeletal, dental, facial parameters. While performing this analysis it becomes very cumbersome for an oral surgeon and orthodontist to discuss the case with all the parameters in mind. So this study was done to determine the parameters of preference for an Oral surgeon and Orthodontist respectively.: 20 Oral surgeons and Orthodontist with 2 years of experience were selected for this study. The selection was done randomly by selecting the specialist through online list. A preferential form consisting of all the parameters of COGS analysis with three preference for each parameter-1): Important, 2): Slightly important and 3): Not so important, were distributed to both the specialists. The forms were collected and the data was tested statistically.Percentage wise preference was determined for various parameters. Majority of Oral and maxillofacial surgeons marked skeletal parameter as important while Orthodontist marked soft tissue as important. There was mutual agreement of preference in various parameters: Anterior cranial base (Ptm-N), Lower anterior face height (Ans-Gn), Upper posterior face height (PNS-N) which was statistically significant. Linear, angular, ratio measurement were preferred differently by oral surgeons and Orthodontists. : Skeletal measurements were preferred by oral surgeons followed by soft tissue & dental relationship, while as Orthodontists preferred Soft tissue, dental measurements followed by skeletal parameters.Cranial base measurements were not so marked as Ist preference by both the specialists.

Combined Effects of Botulinum Toxin Injection and Oral Appliance Therapy on Lower Facial Contouring: A Randomized Controlled Trial.

(1) Background: Botulinum toxin (BoNT) injection is an esthetically effective and safe treatment for contouring the lower face. This study aimed to evaluate the combined effects of BoNT and supplementary oral appliance (OA) therapy on lower facial contouring. (2) Methods: We conducted a prospective randomized controlled trial from January 2015 to June 2016 at the Yonsei University Dental Hospital. Volunteers aged 20–45 years with masseter hypertrophy were randomly assigned to one of two groups: the non-OA group and the OA group. The non-OA group received BoNT injections alone, whereas the OA group received an OA in addition to BoNT injections. Changes in the bulkiest height of the lower face were evaluated by three-dimensional laser scanning before and 4, 8, 12, and 24 weeks after injections in both groups. (3) Results: In both groups, the bulkiest height reductions decreased, with a significant interaction between group (p = 0.046) and time (p < 0.001), although the overall reduction was at a similar level at 24 weeks. (4) Conclusions: The pattern of the bulkiest height reduction of the lower face after BoNT injection differed between standalone treatment and OA therapy, implying a normalizing effect of OA on masseter muscle activity.

Facial skin ageing: Key concepts and overview of processes.

IntroductionThe face is a cosmetically sensitive region where the process of ageing is most clearly manifested. With increased focus on anti‐ageing and longevity, more anti‐senescent treatments are being proposed despite limited evidence. This study outlines the pathways and mechanisms underpinning the biological process of ageing in the face.MethodsComprehensive searches of MEDLINE, EMBASE, Cochrane Library and CINAHL from inception to 2020. Inclusion criteria included all empirical human research studies specific to facial ageing features, written in the English language.ResultsA total of 65 papers met inclusion criteria for analysis. Pathways were subdivided into intrinsic and extrinsic senescence mechanisms. Intrinsic pathways included genetics, generation of reactive oxygen species and hormonal changes. Extrinsic pathways included photoageing and damage to skin layers. The combined intrinsic and extrinsic pathway alterations result in wrinkles, higher laxity, slackness and thinning of the skin. Skin functions such as barrier immune function, wound healing, thermoregulation and sensory function are also impaired.ConclusionThe ageing process is unique to the individual and depends on the interplay between an individual's genetics and external environmental factors. Through understanding the molecular and cellular mechanisms, an appreciation of the consequent structural and functional changes can be achieved. Based on this knowledge, further research can focus on how to slow or impede the ageing process and identify specific targets to develop and evolve new treatment strategies.

Dentoskeletal and soft tissue changes after treatment of crowding with premolar extractions: a 50-year follow-up.

The long-term effects on dentofacial morphology of interceptive treatment with premolar extractions, in the absence of subsequent orthodontic treatment, have not been fully explored. The aim was to investigate the effects of premolar extractions (without subsequent orthodontic treatment) on the dentoskeletal and soft tissue profile of patients aged between 12 and 62 years with Class I malocclusion with severe crowding, as compared to untreated controls. The Extraction group (N = 30 with Class I crowding malocclusion) had their first premolars removed in early adolescence without subsequent orthodontic treatment. The Control group included 30 untreated subjects with Class I normal occlusion. Cephalograms were taken at 12 (T1), 15 (T2), 30 (T3), and 62 (T4) years of age. A superimposition-based cephalometric method was used to assess the dentoskeletal and soft tissue changes. There were no significant differences between the Extraction and Control groups in terms of skeletal sagittal relation, incisor inclination, and protrusion, or most of the soft tissue parameters throughout the observation period. However, significant differences were observed between the groups with respect to the vertical relations in T2-T3, such that the Extraction group showed more-pronounced decreases in the ML/NSL, ML/NL, and Gonial angles and more-pronounced increases in facial heights. Treatment for subjects with Class I malocclusion with severe crowding by the extraction of four premolars, without subsequent orthodontic treatment, does not affect the long-term dentoskeletal and soft tissue profile, as compared to an untreated Control group. The degree of crowding, rather than changes in dentofacial morphology, is crucial in deciding on extraction therapy.

Vertical Skeletal Changes after Extraction and Nonextraction Orthodontic Treatment.

Due to the constant battle regarding the controversial topic of orthodontic extraction, this study aims to assess the changes in vertical dimensions of patients treated with premolar extractions compared with nonextraction orthodontic patients. A sample of 60 borderline patients were recruited and divided into extraction and nonextraction groups. Eleven pretreatment cephalometric measurements were recorded using WebCeph and patients were followed-up until the completion of treatment. Intragroup and intergroup comparisons were made using paired t-test and two-sample independent t-test, respectively. The joint significance of differences was measured using F-tests. The intragroup comparison revealed that in the extraction group, the vertical dimension was significantly increased posttreatment for four cephalometric measurements, that is, mandibular plane angle (p < 0.05), palatal plane angle (p < 0.05), Frankfort mandibular plane angle (p < 0.05), and y-axis (p < 0.05). In the comparison of the posttreatment values of both groups, the mean differences of the posttreatment values for sella nasion (SN)-gonion (Go)-gnathion (Gn) angle (p = 0.008), the total anterior (p = 0.050), and lower anterior facial heights (AFH; p = 0.011) were significantly higher. At the same time, the Jarabak ratio was significantly (p = 0.006) lower in the extraction group than in the nonextraction group. The increase in vertical dimension is significantly higher in the extraction group than in the nonextraction group which indicates a significant impact of orthodontic extraction on the vertical dimensions.

Anthropometric parameters in boys and girls of the Omsk city

The aimof the study was to compare the cephalometric and somatometric parameters of boys and girls aged 18-20 to reveal features of the anthropometry of the youth population of the Omsk city.Material and methods. There was performed an anthropometric examination of 140 people aged 18 to 20 years (70 boys and 70 girls), Slavic ethnic group. Height, transverse chest diameter, chest circumference, body weight, longitudinal and transverse dimensions of the head, full face height, and zygomatic diameter were measured. To obtain generalized data indices of Rees-Eysenck, Rohrer, Quetelet II, Pignet, the head index and the facial index according to Garson were calculated. The data obtained were statistically processed.Results. According to our data, the average height of boys was 180,49±0,73 cm, body weight – 77,28±1,65 kg, average height of girls – 165,79±0,79 cm, body weight – 59,25±1,15 kg. Normosthenic type (44%) prevailed in boys, and asthenic (53%) somatotype prevailed in girls (according to the Rees–Eysenck index). Individuals of both sexes were more likely to have harmonious (57 and 72%, respectively) physical development (according to the Rohrer index). According to the M.V. Chernorutsky index, hypersthenic (44%) somatotype prevailed in boys, and normosthenic (66%) somatotype prevailed in girls. Cephalometry demonstrated that mesocephalic head shape (54%) was more commonly determined in boys, and brachycephalic (50%) head shape - in girls, while euryprosopia was typical for people of both sexes (50% of cases in boys and 63% in girls).Conclusion. The study determined and evaluated typical features of anthropometric data (head shape, face, somatotype) of boys and girls aged 18 – 20 years of the Omsk city.

Comparison of Malocclusion Prevalence, Type and Severity between Cerebral Palsy and Healthy Subjects: A Prospective Case-Control Study

Background: To analyze the prevalence, type and severity of malocclusions in a group of patients with cerebral palsy (CP) using a facial and occlusal analysis and the Dental Aesthetic Index (DAI). Methods: A prospective, case–control study was made of two groups, a cerebral palsy and a control group, with the determination of the facial and occlusion analysis in the three spatial planes. The Dental Aesthetic Index (DAI) was used to assess the severity of malocclusion. Results: The patients with CP presented a higher prevalence of increased facial lower third height and a greater tendency towards right-side canine and molar class II malocclusion, narrower transverse relationship and crossbite. The DAI scores were statistically significantly higher in the CP group. Increased physical impairment in the CP group was associated to greater DAI scores. Conclusions: The prevalence and severity of malocclusion were significantly greater in the CP group. The type of malocclusion predominantly found in these patients was molar class II, with open bite, increased overjet and a narrow arch. The CP group also presented mixed breathing with higher DAI scores and decreased facial lower third height.

Profiles of facial soft tissue changes during and after orthodontic treatment in female adults

BackgroundSome female adults who received orthodontic treatment often complain about thinner faces, protruding cheekbones and sunken temples, even at the beginning of treatment. The present research aimed to explore facial soft tissue changes during and after orthodontic treatment, as well as the related factors affecting facial soft tissue changes.MethodsThis study used 3dMD stereo photography technology to compare facial soft tissue changes among adult females who received orthodontics. A total of 52 adult females (24 teeth extraction, 28 non-teeth extraction cases) were included and potential correlations between related factors (facial morphology features, the change of occlusal height and dental arch width) were evaluated during different treatment periods.ResultsOverall, 3D-negative soft tissue changes of the buccal region moderately correlated with distances of nasion-menton and subnasale-menton (both rs = 0.30, P < 0.05) as well as the ratio of subnasale-menton/right gonion-left gonion (rs = 0.33, P < 0.05) and nasion-menton/right zygomatic point-left zygomatic point (rs = 0.30, P < 0.05). Among the 3D angle measurements, the right chelion-median upper lip point-left chelion angle was found to have a moderate correlation with 3D negative changes of the upper cheilion region (rs = 0.31, P < 0.01). Analysis of occlusal height changes revealed that an increase in the posterior facial height (nasion-gonial distance) may be a risk factor for negative changes in the zygomatic arch area. In addition, a moderate positive correlation between the maxillary first molar width changes and 3D-negative changes of the lower cheek region was found (rs = 0.41, P < 0.05).ConclusionsAfter orthodontic treatment, adult females with wide and short faces may be prone to negative soft tissue changes. Changes of posterior facial height and arch width between the first molars were also risk factors for negative changes of facial soft tissues. Extraction is not a major factor producing facial soft tissue changes.

Cephalometric characteristics of patients with unilateral cleft lip and palate treated using either one- or two-stage palatoplasty

ABSTRACT Purpose The purpose of this study is to compare the changes in maxillary and mandibular growth in patients with unilateral cleft lip and palate (UCLP) after one-stage (Wardill) and two-stage (Perko) palatoplasty. Materials and Methods At initial examination, 45 patients with UCLP and Hellmann’s stage IIIA UCLP who underwent palatoplasty using Wardill’s method and 45 patients who underwent palatoplasty using Perko’s method were included in this study. At the start of the corrective multibracket treatment, 29 patients who underwent palatoplasty using Wardill’s method and 30 patients who underwent palatoplasty using Perko’s method were included in this study. Measurements of cephalometric analysis were compared between the groups. Results In the horizontal direction, less maxillary growth was observed in patients treated using Wardill’s method than in those treated using Perko’s method at initial examination and at the beginning of corrective multibracket treatment. However, both methods led to a smaller maxilla than the reference values of the maxilla. In the vertical direction, the growth of the maxilla was not significantly different between the two groups. However, the direction of mandibular growth differed significantly, indicating that Perko’s method led to a reduction in the lower face height compared with Wardill’s method and reference values. Conclusions In patients who underwent Perko’s palatoplasty, skeletal injustice was improved during orthodontic treatment by extrusion of the maxillary molars and posterior rotation of the mandible.

Characteristic Variants in Long Faces with Increased Anterior Facial Height

Facial characteristics are affected by facial proportions, growth pattern, facial heights and smile of the patients. Long face syndrome usually presents with an increased lower anterior and total anterior facial height, a gummy smile, a hyperdivergent growth pattern and decreased facial height. However, there are many variations in the posterior facial height and the growth pattern. There can be patients having an increased anterior facial height with increased or average posterior facial height, or an average and reduced mandibular plane angle. This paper aimed at reviewing the various characteristic facial variants of an increased anterior facial height. This article reviews three such variants of an increased anterior facial height. It particularly highlights the variant with increased anterior and posterior facial height and the modification in the treatment of such cases. The most common treatment option for the normally occurring variant of hyperdivergent growth pattern with a reduced posterior facial height is surgical superior impaction.

Older adults’ facial characteristics compared to young adults’ in correlation with edentulism: a cross sectional study

BackgroundFacial ageing is a result of superficial wrinkling combined with changes to the underlying soft tissues and skeleton. The influence of tooth loss, as a geriatric characteristic, on facial appearance is still poorly explained. The aim was to evaluate the facial characteristics of older adults, correlate these characteristics with the dentition and make comparisons with young adults using a non-invasive 3D methodology.Methods90 participants older than 65 years, classified into 3 subgroups (edentulous, partially edentulous, toothed) and 30 young adults were evaluated. Their faces were scanned with an optical Artec 3D-scanner. Cephalometric analyses were made using the RapidForm computer program. An independent t-test and ANOVA were used for the comparisons. Pairwise, post-hoc tests were applied with respect to the significant differences (P < 0.05).ResultsThe faces of older adults are wider and longer because of the longer middle facial height. Older adults also have a longer upper lip, a larger nose, a smaller nasolabial angle (due to the nasal ptosis), narrower upper- and lower-lip vermilions and larger facial and lower-facial-height angles, resulting in a flat facial profile.The facial changes due to ageing are the most pronounced in the edentulous. In comparison with the toothed, they have a smaller facial height due to the smaller lower facial height, larger nasolabial angle, smaller mouth width, shorter upper lip and narrower lip vermilions. Their profile is flatter and their lips are more retruded.ConclusionsThe proportions of the whole face are changed in older adults and they are the most expressed when this is combined with tooth loss.

Effect of cervical compensatory curves on malocclusion

Introduction: The purpose of this study was to evaluate and correlate effect of cervical spine curves on the development of class II and class III malocclusion via a comprehensive review of the available literature from previous studies. Materials and Methods: A literature overview was carried out by searching PubMed and Google scholar to analyze the association between “malocclusion” versus “head posture” using MESH keywords. Out of 86 articles, 56 articles were selected for the review. Articles related to gross craniofacial deformities were excluded from the study. Results: Craniocervical posture and facial development according to the literature review seems to be triggered by a large craniocervical angle correlates with a tendency towards posterior rotation of the mandible. Patients with a small craniocervical angle have a smaller lower facial height. A craniocervical angle greater than 113° was primarily associated with vertical facial development having class II malocclusion, whereas an angle less than 79° is characteristic of a horizontal, forward-directed facial growth pattern, having a tendency towards class III malocclusion. Conclusions: The correlation between Angle Class II, having long face syndrome were associated with increased lordosis of the cervical spine. Tendency towards a kyphotic position of neck was associated with Angle Class III patients. Hence there is a significant effect of neck posture on malocclusion. Keywords: Cervical compensatory curves, Malocclusion, Craniocervical angle, Head posture

Comparison Between Cephalometric Measurements Derived from Cone Beam Computed Tomography and Lateral Cephalogram

Objective: To compare the mean craniofacial linear and angular measurements derived from cone beam computed tomography synthesized lateral cephalogram and those obtained from conventional cephalogram.&#x0D; Study Design: Comparative cross-sectional study.&#x0D; Place and Duration of Study: Armed Forces Institute of Dentistry (AFID), Rawalpindi Pakistan, from Feb 2017 to Nov 2018.&#x0D; Methodology: Sample size was 32. Following linear measurements were evaluated; anterior facial height, right side and left side of mandibular length, nasal spine length, Upper and lower incisors to A-Pog distance. These measurements were obtained by both means i.e., conventional cephalogram and cone beam computed tomography synthesized cephalogram. Each of the measurement were taken twice by the single operator with a difference of two weeks.&#x0D; Results: No significant difference was found among measurements obtained through lateral head film cephalograph and cone beam synthesized cephalograph except for mandibular length (for which p=0.04).&#x0D; Conclusions: Cone beam computed tomography synthesized lateral cephalogram can be suggested as a substitute to conventional lateral cephalogram. Especially in conditions when cone beam computed tomography is already required for treatment planning thus reducing supplementary x- ray exposure and expenditure of an additional x-ray.

Iatrogenic retroposition of the lips sequel after bicuspid extraction-a retrospective study

AimThis study aims to explore the prevalence of Iatrogenic retroposition of the lips sequel (IRLS) after bicuspid extraction, associated dentofacial characteristics and the effectiveness of surgical treatment. Materialand methods: Patients with bicuspid extraction as part of an orthodontic treatment plan were retrospectively included. IRLS was identified by clinical evaluation and cephalometric Legan and Burstone analysis. Association of demographic and cephalometric variables were assessed. The effectiveness of combined orthodontic-orthognathic correction of the retroposition of the lips was evaluated. ResultsOut of 144 patients with extracted bicuspids, eight Class I patients, nine Class II patients and five Class III patients were seeking treatment because their lips had retruded as a consequence of compensating orthodontic treatment. Lower jaw bicuspid extraction and a decreased vertical facial height in Class II patients correlated significantly more with IRLS development. Postoperative cephalometric analysis of orthodontic-orthognathic treated patients reported improvement in lip projection and naso-labial angle. Only two Class I patients reported postoperative normalization of the lip position according to Legan and Burstone. ConclusionThe consequence of bicuspid extractions on soft tissue profile differs according to skeletal jaw relation. The impact of orthognathic surgery on IRLS is beneficial, although insufficient to completely correct the facial profile when judged on cephalometric standards.

Volumetric Analysis of the Jaws in Skeletal Class I and III Patients with Different Facial Divergence Using CBCT Imaging.

Aim The main objective was to evaluate any possible maxillary or mandibular volumetric difference between hyperdivergent skeletal Class III (CIII), normodivergent skeletal CIII, hypodivergent skeletal CIII, and normodivergent skeletal Class I (CI) patients using cone-beam computed tomography (CBCT) images. Also, the secondary objective was to investigate any possible correlation between CBCT-derived lateral cephalometric variables and the mandibular and maxillary volumes (MdV and MxV, respectively). Materials and Methods 80 CBCT images of patients between 18 and 32 years of age were taken with one CBCT imaging device (Scanora 3D®, Soredex, Tuusula, Finland). The sample consisted of four groups: 20 hypodivergent skeletal CIII (11 males and 9 females), 20 normodivergent skeletal CIII (7 males and 13 females), 20 hyperdivergent skeletal CIII (8 males and 12 females), and 20 normodivergent skeletal CI (5 males and 15 females). The volumes of both jaws and the ratio of MxV/MdV were obtained using Mimics™ 19 software (Materialise, NV, Belgium), and 2D variables were obtained from CBCT-derived lateral cephalogram using AudaxCeph™ software (Orthodontic software suite, Ljubljana, Slovenia). One-way ANOVA test and Kruskal–Wallis analysis were employed to detect any possible significant difference between the volumetric variables, whereas Pearson's and Spearman's correlation coefficients were calculated to detect any possible relationship between the 2D variables and the volumetric measurements. Results There were no statistically significant differences in the maxillary volume or maxillary/mandibular ratio between the four groups (p=0.081 and 0.432, respectively). There was a significant difference in MdV between CIII hypodivergent (higher mean) and CIII hyperdivergent (p=0.039). There were some correlations between the MdV and 2D variables in the four studied groups especially in the posterior facial height (S-Go) and the facial depth (N-Go). There were some weaker correlations between the MxV and some 2D variables in the CIII hypodivergent and hyperdivergent groups. Conclusions The mandibular volume of the Class III hypodivergent patient was significantly greater than that of the Class III hyperdivergent patients. Correlations between the maxillary or mandibular volumes were found with some of the 2D variables. The volume of both jaws increased when the maxillofacial complex moved toward a horizontal growth pattern.

Growth of teeth and bones in adult subjects with congenital untreated isolated growth hormone deficiency

ObjectiveTo understand the growth of teeth and mandibular and maxillary bones in subjects with isolated growth hormone deficiency (IGHD). Material and methodsMesiodistal tooth width of 28 maxillary and mandibular dental models of 14 adult IGHD subjects (9 men) were digitalized and compared to 40 models of 20 normal-statured controls (11 men). The mean SDS of the maxillary and mandibular teeth were compared with height, cephalic perimeter, total anterior facial height, total maxillary and mandibular length, and maxillary and mandibular arches. ResultsAll average mesiodistal dimensions in absolute values of the 14 dental pairs were reduced in the IGHD group. Eight of 28 (28.6%) mesiodistal dimensions in IGHD subjects of both sexes had an average SDS below −2, thirteen of them (46.4%) had mean SDS between −1 and − 2, and seven of them (25.0%) had SDS above −1. The highest SDS values were the upper lateral incisor (−0.32 in women), and the upper canine (−0.91 in men). The lowest SDS values were the 2nd upper molar (−3.51 in men), and the 2nd upper premolar (−2.64 in women). The ascending order of the mean SDS was height, total maxillary length, total mandibular length, total anterior height of the face, cephalic perimeter, the maxillary arches width, the mesiodistal width of the mandibular teeth, the mesiodistal width of the maxillary teeth and the mandibular arches width. ConclusionsReduction in mesiodistal width is present in untreated IGHD adults with magnitude of tooth size reduction being lower than height, cephalic perimeter, total anterior facial height, and most jaw measurements. IGHD abolishes the sexual dimorphism in mesiodistal dental measures.

Total inferior border ostectomy versus T-shape genioplasty for chin narrowing combined with mandibular contouring

The objective of this study was to compare the indications and outcomes of the total inferior border ostectomy and T-shape genioplasty. A retrospective study was conducted using the clinical notes and records of patients who underwent total inferior border ostectomy (group 1, n = 42) and T-shape genioplasty (group 2, n = 60). The outcomes were evaluated by assessment of computed tomography images combined with medical records and photographs. Lower facial height, chin width, chin symmetry, and facial proportions, as well as patient satisfaction and complications were investigated. The data were collected preoperatively and 6–24 months postoperatively. All 102 patients showed an improved lower facial contour. No severe complications were observed during the follow-up period. Although the postoperative lower to midfacial height ratios were similar in the two groups (P = 0.080), both the preoperative and postoperative chin width to lower facial height ratios were lower in group 1 (both P < 0.001). A larger amount of chin narrowing, as well as better chin symmetry were observed in group 1 (P < 0.001). In conclusion, compared to the T-shape genioplasty, the total inferior border ostectomy is well suited for a longer, wider, and more asymmetrical chin. The surgical options should be considered and chosen quantitatively to achieve aesthetically pleasing results.

Description of Clinical Facial Analysis of Minangkabau Ethnics Students Using Rhinobase Software

BACKGROUND: Facial analysis is influenced by several factors including age, gender, race, body shape, and personality. The anatomical characteristics of Asians are highly varied. The differences of these characteristics have become a reference for several researchers to get the basic value of each individual facial profile from certain regions or countries.&#x0D; AIM: To determine the clinical facial analysis of students from the Minangkabau ethnic group.&#x0D; MATERIAL AND METHOD: A descriptive-analytic study with a cross-sectional design was carried out on 100 students of the Faculty of Medicine, Andalas University, ethnic Minangkabau aged 18 to 29 years who met the criteria. Facial analysis using Rhinobase Software, the results obtained were analyzed using the Statistical Package for the Social Sciences (SPSS) version 22&#x0D; RESULTS: This study showed that there were significant differences (p&lt;0.05) in 8 of 21 facial anthropometric parameters. Those parameters were LFH, SM, Mf-Mf, Al-Al, MCA, NT, tip Powell projection, and mentolabial sulcus.&#x0D; CONCLUSION :&#x0D; The vertical facial assessment revealed that men have a longer lower facial height than women. The horizontal facial assessment found that men have a wider bridge of nose and nostrils than women.

Опыт применения гидравлических экскаваторов в сложных горно-геологических и климатических условиях

The article summarizes the experience of using hydraulic excavators in coal, diamondiferous and other mining operations. It is noted that the excavation capacity of modern hydraulic excavators is several times higher than that of the mechanical shovels, and the hydraulic equipment is more suitable for non-explosive excavation in hard grounds, including halfrock formations. It is shown that even in difficult mining, geological and climatic conditions in coal, diamondiferous and other mines, the use of hydraulic excavators in Russian mining companies is justified by high efficiency and high availability ratio equal to the international indicators, which are not lower than those achieved in much more favorable conditions. Research performed in industrial settings made it possible to determine the hydraulic drive's service mode and regulations, as well as rational operating conditions. Operating systems were developed with heated working fluids to compensate for the changing viscosity at low atmospheric temperatures. Based on the tests performed in Russia and abroad, blast-free excavation using hydraulic excavators is done with limited capacity (up to 400 m3/h), and the operating weight of the machines must be not less than 300 tons. The main factors, typical for operation of the open-pit hydraulic excavators include the high annual production time, high forces and dynamics (up to 70 kN per 1 m3 of the bucket capacity) in the digging mode of the unit working at the face, high specific capacity and remoteness from the outside infrastructure used for repairs of the hydraulic components. In the course of testing the hydraulic excavators, the boundary values of the face slope angle depending on the ambient temperature were established. It was experimentally proved that at top to bottom layer-by-layer excavation with the H-285S hydraulic shovel the face height can reach up to 25 m at the rated digging height of 16 m. The average lump size (not more than 300 mm) of the rock mass in a 19 m3 bucket was determined with the permissible oversize in the face up to 2,500 mm. With the normal maintenance quality, the weighted average cost of operation for electromechanical excavators and the corresponding figures for hydraulic excavators are at a comparable level.

Do Specific Craniomaxillofacial Features Correlate with Psychological Distress in Adult Pretreatment Orthodontic Patients? A Cephalometric Study.

Purpose To explore the relationship between craniomaxillofacial features and psychological distress among adult pretreatment orthodontic patients. Methods A group of 190 patients (95 males and 95 females) was included. Questionnaires including the Kessler psychological distress scale (K10) were sent to patients, and cephalograms were collected. Patients were divided into two groups according to K10 score: psychological distress group (score ≥ 20) and no psychological distress group (score < 20). Nineteen hard tissue and thirteen soft tissue parameters were traced on cephalograms to characterize the craniomaxillofacial features. Results There was no significant difference in gender or age distribution between the two groups. Male patients with psychological distress showed statistically significantly larger anterior facial height (AFH) (126.62 mm vs. 120.97 mm), upper lip length (25.11 mm vs. 23.26 mm), and smaller overbite (1.21 mm vs. 2.75 mm) than patients without psychological distress. Male patients with hyperdivergent pattern and open bite were more likely to have psychological distress. None of the parameters showed statistical differences across groups in females. Frankfort-mandibular plane angle (r = 0.235), Bjork's sum (r = 0.311), AFH (r = 0.322), overbite (r = −0.238), AFH/posterior facial height (r = 0.251), and upper anterior facial height (UAFH)/lower anterior facial height (LAFH) (r = −0.230) were correlated with K10 score in males. After adjusting gender and age, the AFH (B = 0.147) and UAFH/LAFH (B = −14.923) were significantly related with the K10 score. Conclusion Psychological distress was mainly correlated with hyperdivergent pattern, open bite, and larger lower anterior facial height proportion in pretreatment orthodontic patients. Orthodontists should be aware of the possible underlying psychological distress in patients with specific craniomaxillofacial features. Clinical assessment of psychological distress may need to take into account gender differences in patients.