Keywords :
mandibular anterior crowding, third molar eruption level, third eruption space, third molar angulation
Citation Information :
Sood A, Bhullar M, Mittal S, Aggarwal I, Singla D, Sharma A. Relationship of Mandibular Third Molar to Mandibular Anterior Crowding. 2018; 6 (2--3):89-96.
Introduction The impact of third molars in occurrence of secondary mandibular incisor crowding has been a disputable subject and is reviewed in the dental literature for many years. The relationships between lower third molar angulation, eruption level, and eruption space to lower anterior crowding are not completely understood.
Aim To evaluate the relation between the third molar angulations, eruption space, eruption level, and mandibular anterior crowding.
Materials and Methods Pretreatment plaster study models (mandibular dental arches) and orthopantomograph of 40 individuals, aged between 12 and 22 years, were part of the study. The whole sample was divided into two groups based on the Little's index of irregularity: group I—control group (n = 20) composed of patients with index 0 to 3 mm, and group II—study group (n = 20) composed of patients with index > 3 mm. Calculations were made for the third molar eruption depth, eruption space, and angulation.
Statistical Analysis Mean values were compared for selected dimensions between the control and study groups with Student's t-test.
Results Statistically significant differences for Ganss ratio in right side between the control and study groups with a p-value of 0.049 were observed. Statistically insignificant difference was seen between the control and study groups for other parameters. Eruption level B was found for maximum molars in the study group, 95% on right and 85% on left side.
Conclusion It was inferred that no strong relation exists between the third molar eruption level, space, and angulations to mandibular anterior crowding.
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