Relationship of maxillary and mandibular effective base length, arch length and dental crowding in different vertical growth pattern

Objectives: The objectives of the study were to assess, measure, and correlate the maxillary and mandibular effective base length, arch length to the amount of dental crowding in different vertical growth pattern patients. Materials and Methods: Sample comprising 100 pre-treatment lateral cephalograms and study models (age group – 16–25 years) was randomly selected. The sample was divided into two groups, that is, clockwise (50) and anticlockwise (50) rotation based on the measurement of the gonial angle. The gonial angle and maxillary and mandibular effective lengths were measured on pre-treatment lateral cephalograms. Dental crowding and arch length were measured on the pre-treatment dental casts. Intergroup comparisons of effective base length, arch length, and crowding were performed with unpaired t-tests. Correlations between effective base length, arch length, and dental crowding were examined by means of Pearson’s correlation coefficient (P < 0.05). Results: Subjects with clockwise rotation significantly had more mandibular dental crowding and significantly decreased mandibular arch length compared to the anticlockwise group. An inverse correlation was found between maxillary and mandibular effective base length, arch length, and dental crowding while a positive correlation was found between maxillary and mandibular base length and arch length in both the groups. Conclusion: Clockwise rotation of the mandible along with skeletal and dental factors such as decreased effective base lengths and arch length, respectively, constitutes an important factor leading to dental crowding.

Orthosurgical management of skeletal class-II malocclusion with vertical growth pattern- A case report

Edward H Angle first gave the classification for malocclusions into Classes I, II and III. Amongst these, Class II is the most prevalent and commonly treated at orthodontic clinics. Treatment of Class II malocclusion with mandibular deficiency in adult patients is usually managed with ortho-surgical treatment modality. In this article a case of Skeletal Class II malocclusion with vertical growth pattern is represented which was treated with BSSRO and mandibular advancement was carried out.

Vertical Proportion of the Face: A Cephalometric study

Introduction: Balance in vertical facial proportion is an important criteria for good esthetics. Variations in vertical growth are common and have certain orthodontic implications. The objectives of this study were to determine mean upper anterior facial height and lower anterior facial height, ratio between UAFH to LAFH and their difference among genders in skeletal Class I patients with different vertical growth pattern among patients visiting department of Orthodontic and Dentofacial orthopedics, Tribhuvan University Dental Teaching Hospital, Kathmandu. Materials and Method: This study was descriptive observational cross sectional study with 105 sample aged from 18-25 years. Pretreatment cephalometric radiograph of Skeletal Class I patients were taken and divided into three growth patterns as group I (normal growth pattern), group II (horizontal growth pattern ) and group III (vertical growth pattern ). Upper anterior facial height (N-ANS) and lower anterior facial height (ANS-Me) of all samples were measured on lateral cephalogram with cephalometric tracing ruler parallel to true vertical line. Descriptive statistics was used to calculate mean, minimum, and maximum values standard deviations with p value <0.05. Result: The upper anterior facial height (UAFH) and lower anterior facial height (LAFH) measurements in normal growth pattern was 52.37 and 64.4 , in horizontal growth pattern was 53.0 and 62.2, in vertical growth pattern was 53.37 and 64.42 respectively. The mean ratio of upper and lower anterior facial height in normal, horizontal and vertical growth pattern was 0.81, 0.85 and 0.79 respectively. There was no statistically significant difference in upper and lower facial heights between males and females. There was no statistically significant difference in UAFH between normal, horizontal and vertical growth pattern but statistically significant difference was observed in LAFH between groups. Conclusion: The cephalometric values for different vertical groups in skeletal class I can be used more specifically for diagnosis and treatment planning of Nepali population.

Personalized Orthodontics: From the Sagittal Position of Lower Incisors to the Facial Profile Esthetics

Background: One of the goals of orthodontic treatment is to obtain maximum facial harmony. The sagittal position of the lower incisors plays a significant role in the planning of orthodontic treatment. The aim of the study was to evaluate the relationship between the sagittal position of lower incisors and facial profile esthetics with reference to the skeletal vertical dimension. Methods: There were 200 patients included in the study. Patients were allocated into three groups, depending on the vertical growth pattern: normal-angle, low-angle, and high-angle cases. Tweed–Merrifield cephalometric analysis was used to assess the sagittal and vertical position of the mandible, as well as to assess the sagittal position of the lower incisors. Results: Z-angle and Frankfort mandibular incisor plane angle (FMIA) decreased significantly (p < 0.001) with the increase of the skeletal vertical dimension. Incisor mandibular plane angle (IMPA) was significantly higher (p < 0.001) in low-angle patients compared to the high-angle ones. Z-angle appeared to be the most accurate parameter (area under curve, AUC = 0.957) describing patients with a convex profile. The cutoff value of Z-angle 68.0° was characterized by the sensitivity of 94.1% and the specificity of 84.3%. Conclusions: The sagittal position of the lower incisors significantly affects the facial profile convexity. The Z-angle is the parameter which most accurately describes the patients with a convex profile.

Measurement of inter radicular bone width in different growth patterns for determining safe zone for placement of miniscrew implants – A cone beam computed tomography study

To measure the inter-radicular spaces in both arches for miniscrew implant placement and to determine the most reliable sites using CBCT. A CBCT radiograph was taken for 75 subjects that met with inclusion criteria. They were divided into 3 categories- Hypodivergent, average, and hyperdivergent group. Images were calibrated by using software and printed as a film. Interradicular space on the right side of the jaw was measured in the sagittal plane after assuming the jaw to be symmetrical. Bucco-lingual and mesiodistal width were measured up to desired bone levels. In vertical growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar at 7mm. In the mandible, it was between the 1st and 2nd molar at 11mm. In horizontal growth pattern, in posterior maxilla highest mesiodistal width between 1st and 2nd premolar, and mandible it was between 1st and 2nd molar at 11mm. In average growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar and 1st molar at 7mm. In the mandible, it was between the 1st and 2nd molar at 11mm. The importance of the relationship between the growth pattern and the availability of inter radicular space may aid the clinician in planning appropriate surgical sites for miniscrew implant placement.

Correlation of Growth Pattern and Palatal Rugae Pattern in South Indian Population

Aim: To determine the correlation between palatal rugae (PR) pattern and subjects with vertical, average, and horizontal growth pattern and to determine gender variation if any. Material and Methods: One hundred and twenty study models were divided into horizontal, vertical, and average growth patterns with 40 (20 males and 20 females) samples in each group. The pattern of PR was assessed in each group using a template. Result: Type B (wavy type) PR occurs more often in horizontal and average growth pattern (80% and 72.5% respectively), whereas its occurrence in vertical growth pattern subject is the least among other growth patterns, that is, 42.5% of the total subjects. Type E (curved type) PR has appeared highest in 27.5% of average growth pattern patient followed by 12.5% of vertical growth pattern subjects. The occurrence of type E PR is least in horizontal growth pattern which is just 5% of the total subjects. Conclusion: Curved-type PR was more prevalent in vertical and average growth patterns. Diverging PR pattern was mainly seen in vertical growth pattern. PR also shows sexual dimorphism. The association is clinically significant as it will lead to determination of facial vertical growth pattern at early age; thus, it serves as a diagnostic adjunct for different malocclusions very early in life and aids in preventive or interceptive orthodontic measures to alleviate forthcoming growth pattern.