Online ISSN: 2515-8260

Author : George, Ashwin Mathew


CORRELATION BETWEEN ANTEGONIAL NOTCH DEPTH, SYMPHYSIS MORPHOLOGY AND RAMUS LENGTH IN DIFFERENT GROWTH PATTERNS OF ANGLE’S CLASS II DIV 2 SUBJECTS

S. Abirami; Ashwin Mathew George; Remmiya Mary Varghese

European Journal of Molecular & Clinical Medicine, 2020, Volume 7, Issue 1, Pages 1134-1149

In orthodontics and dentofacial orthopaedics ,thorough knowledge of skeletal and dental components that contribute to Angle’s class II div 2 malocclusion is essential because these elements may influence the approach to treatment.When planning of orthodontic treatment for malocclusion, one has to take into account the growth pattern , because it would considerably affect the success of the treatment. Facial growth and development is important because amount and direction growth will alter the need for orthodontic biomechanics.The aim of this study was to compare between antegonial notch depth, symphysis morphology, and ramus morphology in different growth patterns in skeletal class II div 2 subjects. In this study, lateral cephalograms of 47 skeletal class II div 2 subjects were traced. The sample was divided into average, horizontal, and vertical growth patterns based on jarabak’s ratio. An analysis of variance (ANOVA) test was performed to determine the comparison between groups for all these variables.Pearson correlation coefficient analysis was done to determine correlation between all variables within all the groups. Results showed that Depth of antegonial notch is found to be greater in vertical growth patterns compared to horizontal and average growth patterns. Large symphysis angle and symphysis width is noted in the horizontal growth pattern. Small ramus height is noted in vertical growth pattern compared to horizontal and average growth patterns. In horizontal growth pattern antegonial notch depth was found to be highly correlated with symphyseal angle (r=0.374) and low correlation was found with symphysis width (0.147) and ramus length(r=0.178).In vertical growth pattern , antegonial notch depth was found to be highly correlated with symphyseal angle (r=0.353) and negative correlation was found with ramus length (r = -0.021),symphysis width (r= - 0.676).In average growth pattern , antegonial notch depth was found to be highly correlated with ramus length(r=0.169) and low correlation was found with symphysis width (r=0.033) and negative correlation was found with symphysis angle (r=-0.403).This study concluded that antegonial notch depth ,symphysis morphology and ramus height are significantly correlated with different growth patterns in skeletal class II malocclusion but are highly significant in horizontal growth patterns. All parameters are significantly correlated with different growth patterns.

ROLE OF PAX9 AND MSX1 GENE POLYMORPHISM IN CONGENITALLY MISSING LATERAL INCISORS – A SYSTEMATIC REVIEW

Seerab Husain; Ashwin Mathew George; Sri Rengalakshmi

European Journal of Molecular & Clinical Medicine, 2020, Volume 7, Issue 1, Pages 397-411

Aim:
The aim of this study was to evaluate and review articles and researches done on the polymorphism of PAX9 and MSX1 genes in congenitally missing lateral incisors.
Materials and methods:
A thorough search of the electronic database through Cochrane library, PubMed central, LILACS and BMC and manual hand searching of orthodontic journals was done till March 2020. The keywords included in the search were: “Genetics”, “lateral incisors”, “agenesis”, “PAX9”, “MSX1”. The studies were selected as per the PRISMA guidelines. Articles were shortlisted based on the exclusion and inclusion criterias. Of all the obtained results, 12 studies were selected based on the inclusion criteria and they were analysed for the role of polymorphism of PAX9 and MSX1 genes in the congenitally missing lateral incisors.
Results:
Results of this systematic study show an association of PAX9, EDA and WNT10A gene pleomorphism with congenitally missing lateral incisors. MSX1 gene however is not shown to have an association with lateral incisor agenesis.
Conclusion:
This systematic review has provided a clear view on the role of the pleomorphism of different genes on the agenesis of lateral incisors, which will help the reader understand the problem better and handle it with better precision. Future studies are required to further conduct more randomised controlled trials, which will provide more concrete evidence to the claims.
Clinical significance:
Maxillary lateral incisors are the third most common congenitally missing teeth in the human dentition, preceded only by the third molars and mandibular second premolars The cause of lateral incisor agenesis is thought to be rooted to a genetic etiology.