Comparison Of Soft Tissue Chin And Lower Lip Thickness In Adult Patients With Various Mandibular Divergence Patterns.

BACKGROUND: The influence of hard tissue discrepancies on soft tissue cannot be ignored. The divergence or angle of the mandible can influence the lower lip and chin (soft tissue), similar to the influence of incisors inclinations on the pro/ retrusion of the lips. Hence this study was carried out to find out the impact of mandibular divergence patterns on the contour and thickness of lower facial soft tissues. METHODS: Using the Lateral cephalograms of 105 subjects, Lip thickness was measured between the protruding endpoint of the maxillary incisors (U1) to the stomion point (St) and between the infra dentale (Id) and labrale inferius (Li). Soft tissue chin thickness was measured between the landmarks at hard tissue bony pogonion (Pog) to its opposite point on soft tissue (Pog'), hard tissue gnathion (Gn) to soft tissue gnathion (Gn') and hard tissue menton (Me) to its opposite point on ST menton (Me'). RESULTS: Lower lip thickness from Id-Li (infradentale labrale inferius) was greater in subjects with mandibular hyperdivergent pattern (p-value 0.097) while soft tissue chin thickness was decreased in hyperdivergent and increased in individuals with mandibular hypodivergence in both genders (p-value at gnathion was 0.596, menton was 0.023, and pogonion was 0.004, respectively). CONCLUSIONS: Lower lip thickness was increased in the individuals with mandibular hyperdivergence measured from infradentale to labrale inferius. While increased soft tissue thickness was observed at points gnathion and menton in patients with mandibular hypodivergence with no obvious difference at pogonion point.

Effect of lower facial height and anteroposterior lip position on esthetic preference for Korean silhouette profiles.

OBJECTIVE: The purpose of this study was to evaluate the esthetic preference for various Korean silhouette profiles. METHODS: The Korean average male and female profiles were modified by changing the lower facial height and anteroposterior lip position to produce nine types of profiles. In order to test intrarater reliability, the average profile was copied once more to be included for evaluation. A questionnaire containing 10 profiles for each sex, each of which had to be rated for preference on a numerical rating scale from 0 to 10, was administered to 30 adult orthodontic patients, 30 dental students, 30 orthodontists, and 30 dentists excluding orthodontists. The data were statistically analyzed using the intraclass correlation coefficient (ICC), independent t-test, and one-way ANOVA. RESULTS: The ICC of overall intrarater reliability was 0.629. For several profiles, significantly higher scores were given to male profiles than to female profiles (p < 0.05). However, no significant differences were found in the scores for all profiles among the four rater groups. Among the short profiles, a significantly higher score was given to the retruded profile, and among the vertically average and long profiles, a significantly higher score was given to the horizontally average profile (p < 0.001). Among all the profiles, significantly lower scores were given to the protruded profile (p < 0.001). CONCLUSIONS: This study revealed good overall intrarater reliability, with several types of male profiles being esthetically preferred over female profiles. Moreover, while retruded and horizontally average profiles were generally preferred, protruded profiles were not.

The effect of tooth wear, age and sex on facial height assessed by soft tissue analysis.

AIM: The aim of the study was to evaluate the effects of tooth wear, age and sex on facial height measurements based on soft tissue analysis. METHODS: One hundred and twelve subjects (45 males and 67 females), 19-80 years of age (mean 43 ± 0.9 years), which were divided into three age groups, met the inclusion criteria. Tooth wear was assessed using a 5-point ordinal scale (0-4). Based on the tooth wear score, three groups were defined: mild, moderate and severe wear. Facial height was evaluated based on soft tissue measurements using frontal facial photographs. The dimension of the upper facial height (UFH) and lower facial height (LFH) and the ratio between the two (R-U-L) were measured. RESULTS: Facial height dimensions (UFH, LFH) were significantly different between the three age groups and between the three tooth wear groups. Both the UFH and LFH measurements had a weak positive correlation with age (r = .40; r = .41, respectively) and with tooth wear (r = .40; r = .41, respectively). The R-U-L showed a significant difference (P < .001) between sexes as males showed slightly lower ratio compared with females; however, the R-U-L was not dependent upon age or tooth wear. CONCLUSIONS: This study demonstrated that although facial height is affected by age and tooth wear, the proportion between the upper to lower facial segments is constant and is not affected by the same parameters. A statistically significant difference in the R-U-L relative to sexes was noted.

Digital Cephalometric Tracings by PRO-CEPH V3 Software for Comparative Analyses of Vertical Dimension in Edentulous Patients.

BACKGROUND: Several methods, some physiological, some radiographical and some merely based on experience are taken upon by the practitioner to get him/her close to VDO in the edentulous patients. No single method can however claim to be the perfect answer. Lateral cephalograms have been a standard mode of determining the vertical dimensions in dentate and edentulous patients since the past. Due to unavoidable manual errors, there are chances of variations in the radiographic method too. Advancement in the digital technology has made recording jaw relations faster, simpler and more precise. AIM: This study compared the vertical dimension of occlusion in edentulous patients recorded by using three different physiological methods with the aid of digital cephalometric tracings using indigenously developed PRO-CEPH V3 software. MATERIALS AND METHODS: For the present study a total of 50 dentulous and 25 edentulous patients were selected through inclusion and exclusion criteria. A lateral cephalometric radiograph was taken for all the 50 dentulous subjects at Maximum Intercuspation (VDO) whereas three lateral cephalometric radiographs were obtained for all edentulous patients at the VDO following three different techniques- the Niswonger's method, Phonetics method and Swallowing threshold method. Cephalometric tracings were carried out using indigenously developed PRO-CEPH V3 software. Linear and angular measurement were made and analysed. CONCLUSION: The indigenously developed software PRO-CEPH V3 is capable of making both the linear and angular measurement and therefore provide with relative credibility information regarding the possible VDO in the edentulous patients through cephalometric radiography.

A Newly Proposed Method to Predict Optimum Occlusal Vertical Dimension.

PURPOSE: Establishing the optimum occlusal vertical dimension (OVD) in prosthetic treatment is an important clinical procedure. No methods are considered to be scientifically accurate in determining the reduced OVD in patients with missing posterior teeth. The purpose of this study was to derive a new formula to predict the lower facial height (LFH) using cephalometric analysis. MATERIALS AND METHODS: Fifty-eight lateral cephalometric radiographs of Japanese clinical residents (mean age, 28.6 years) with complete natural dentition were used for this study. Conventional skeletal landmarks were traced. Not only the LFH, but six angular parameters and four linear parameters, which did not vary with reduced OVD, were selected. Multiple linear regression analysis with a stepwise forward approach was used to develop a prediction formula for the LFH using other measured parameters as independent variables. RESULTS: The LFH was significantly correlated with Gonial angle, SNA, N-S, Go-Me, Nasal floor to FH, Nasal floor to SN, and FH to SN. By stepwise multiple linear regression analysis, the following formula was obtained: LFH (degree) = 65.38 + 0.30* (Gonial angle; degree) - 0.49* (SNA; degree) - 0.41* (N-S; mm) + 0.21* (Go-Me; mm) - 15.45* (Nasal floor to FH; degree) + 15.22* (Nasal floor to SN; degree) - 15.40* (FH to SN; degree). CONCLUSIONS: Within the limitations of this study for one racial group, our prediction formula is valid in every LFH range (37 to 59°), and it may also be applicable to patients in whom the LFH deviated greatly from the average.

Avaliação da proporção facial vertical: relação entre as alturas tegumentar e esquelética / Evaluation of facial proportions in the vertical plane to investigate the relationship between skeletal and soft tissue dimensions

OBJETIVO: determinar a relação entre as alturas faciais obtidas na avaliação do tegumento e do esqueleto subjacente, na análise da proporção facial vertical, na região anterior. MÉTODOS: foram utilizadas 24 radiografias cefalométricas de perfil e 48 fotografias da face, sendo 24 de perfil e 24 frontais, pertencentes a 24 indivíduos brasileiros, 7 do sexo masculino e 17 do feminino, na faixa etária de 19 a 38 anos. Foram realizados traçados cefalométricos e, sobre esses, obtidas medidas lineares, segundo as análises preconizadas por Schudy, Wylie e Johnson e Thompson e Brodie. Sobre as fotografias faciais, foram demarcados os pontos glabela, subnasal e mento, o que permitiu a medição das distâncias lineares entre os mesmos. Os dados obtidos foram, então, tratados estatisticamente. RESULTADOS E CONCLUSÕES: encontrou-se correlação positiva entre as avaliações do tegumento e do esqueleto subjacente, com base nas análises de Schudy (r=0,619, p<0,001), Wylie e Johnson (r=0,595, p<0,002) e Thompson e Brodie (r=0,630, p<0,001), embora, individualmente, algumas discordâncias tenham sido identificadas, devido à variabilidade em espessura nos tecidos moles.

OBJECTIVE: To determine the relationship between facial heights by evaluating the soft tissues and underlying skeleton and by analyzing vertical facial proportions in the anterior region. METHODS: The study used 24 lateral cephalometric x-rays and 48 photographs of the face, 24 in profile view and 24 in front view, belonging to 24 Brazilian individuals, 7 men and 17 women whose ages ranged from 19 to 38 years. Cephalometric tracings were performed and linear measurements obtained according to the analyses suggested by Schudy, Wylie & Johnson, and Thompson & Brodie. The anatomical landmarks glabella, subnasal and menton were identified on the photographs, which allowed the measurement of linear distances between these points. The data were then statistically analyzed. RESULTS AND CONCLUSIONS: A positive correlation was found between evaluations of the soft tissues and underlying skeleton based on the analyses advanced by Schudy (r=0.619, p<0.001), Wylie & Johnson (r=0.595, p<0.002) and Thompson & Brodie (r=0.630, p<0.001), although, individually, some discrepancies were identified due to variability in soft tissue thickness.

Changes in Tongue Position, Airway Width, Gonial Angle, Lower Facial Height after Bilateral Sagittal Split Ramus Osteotomy in Mandibular Prognathic Patients

INTRODUCTION: In patients with mandibular prognathism, Bilateral Sagittal Split Ramus Osteotomy(BSSRO) combined with orthodontic treatment reduces oral volume and influences tongue and other surrounding tissues. Purpose of this study was to analyze post-operative tongue position and airway dimension, as well as mandibular changes in vertical, horizontal, and angular dimensions. MATERIALS AND METHODS: Height of dorsum of tongue, width of airway, gonial angle and lower facial height of mandibular prognathic patients who visited Kangdong Sacred Heart Hospital from Jan. 2001 to Dec. 2006 were anaylzed via pre-operative and post-operative cephalograms. T-test was used to compare pre-operative and post-operative measurements. Also, correlations among pre-operative measurements of the patients were analyzed. RESULTS AND CONCLUSION: A significant correlation was shown between ANS-Xi-PM area and location of dorsum of tongue in pre-operative patients. A significant superior movement of tongue and decrease of airway width was observed in post-operative patients. Also the upper gonial angle decreased significantly.

Treatment effect of face mask therapy for Class III malocclusion patients according to low facial morphology / 대한치과교정학회지

OBJECTIVE: Improvements in jaw relationship through clockwise rotation of the mandible may be desirable in some Class III patients with short low facial height. The aim of this study was to examine the treatment effect of face mask for Class III malocclusion patients according to their low facial morphology. METHODS: Class III patients in their pubertal growth period were divided into two groups (Group 1, high LFH; Group 2, low LFH) according to lower facial height (LFH) by Ricketts (norm, 47). Treatment changes between groups after face mask treatment was compared not only for hard tissue but also for soft tissue. RESULTS: There were no significant differences between the two groups for the skeletal and soft tissues of the maxilla. There were no significant differences between the two groups for the skeletal posterior movement of the mandible, but posterior movement of the mandibular soft tissues in group 2 was larger than group 1. There were no significant differences between the two groups for the vertical hard tissue proportion changes of the mandible, but the vertical soft tissue proportion changes of the mandible in group 2 was larger than group 1. There was a significant correlation between the sagittal hard tissue and soft tissue changes of the maxilla and mandible, but there was no significant difference in the vertical changes. CONCLUSION: The clockwise rotation of the mandible occurred from use of the face mask, and posterior movement of soft tissues of the mandible was higher in Cl III patients with low LFH than with high LFH.

Level of perception related to changes in lower facial height / 대한치과교정학회지

Understanding the level of a person's perception of changes that have occurred on the face after orthodontic treatment is critical to the process of orthodontic diagnosis and treatment planning. The purpose of this study was to determine the level of perception of profile and frontal changes in lower facial height. Forty students attending art school participated in a study evaluating the level of a participant's perception of changes in the lower facial height. Participants compared computer-graphic frontal and profile photographs with balanced proportions and photograph simulations of 1, 2, 3, and 4 mm changes in lower facial height from stomion to the chin. At least a 2 mm change in lower facial height for the profile view and 3 mm in the frontal view was needed to be perceived after orthodontic treatment. The level of a person's perception of the change in lower facial height was more sensitive in the profile view than in the frontal view, and information about facial changes given prior to evaluation enhanced the level of perception.

A study on the pattern of skeletal change following cervical headgear therapy in growing children / 대한치과교정학회지

This study was to investigate the horizontal & vertical bone change pattern when using cervical headgear in Class II malocclusion of growing children and compared the skeletal features between the group with increased lower facial height and the group without increase in lower facial height. The results are as follows; 1. Forward growth of maxilla was inhibited, downward tipping of anterior palatal plane could be seen and distal movement of maxillary first molar was observed. 2. There was relative forward movement of Mandible against the Maxillary cranial base, and relative forward movement of mandibular 1st molar against the Maxilla and vertical increase due to alveolar growth of Mandible. 3. There was significant increase in anterior and posterior facial heights but the ratio of facial height showed no significant difference. 4. The group with increased lower facial height has shorter ramus length, than the smaller palatal plane angle, and more distal movement of Maxillary 1st molar than the group without increase Ha-young Hyun.