Effects of premolar extractions on Bolton overall ratios and tooth-size discrepancies in a north Indian population

Abstract

Aim:The purpose of this study was to evaluate the Bolton overall ratio in a north Indian population reporting for orthodontic treatment and to determine the effect of extractions on the Bolton ratios. Another aim of the study was to check the effects of different extraction patterns on the final Bolton ratio.Materials and Methods:One hundred and twenty pre-treatment dental casts (60 males and 60 females) of orthodontic patients were selected randomly. Mesio-distal dimensions of the mandibular and maxillary teeth were measured before treatment, and subjected to Bolton analysis. Hypothetical tooth extraction by the following combinations: All the first premolars, all the second premolars, upper first and lower second premolars and upper second and lower first premolars were performed for each patient. The measurement results were again subjected to Bolton analysis to see whether any tooth-size discrepancy had been created.Results and Conclusion:The tooth material ratio of the studied north Indian population shows a mild maxillary tooth material excess. Extraction of premolars in any combination causes the maxillary tooth material to further increase. There is no significant sex difference in the tooth material ratios with or without extractions. In patients requiring extraction; all first premolar extraction or maxillary first and mandibular second premolar extraction should be preferred. For deciding a treatment plan involving extraction of teeth, we need to consider that the maxillary tooth mass may increase after extraction. Furthermore, the normal or the clinically significant tooth size discrepancies may change following extraction of teeth.

The Effect of Premolar Extractions on Tooth Size Discrepancies in Different Malocclusion Groups of Egyptian Sample

“…However, the number of cases who have small Bolton's overall ratios was increased after all combinations of premolar extractions especially after extraction of maxillary first and mandibular second premolars or maxillary second and mandibular first premolars, the mean values of normal Bolton's over all ratios group almost not affected after extractions of all first or maxillary first and mandibular second premolars (the mean differences were -0.13 and 0.01 respectively). These results were compatible with the finding of Kumar et al; 2013 (36) and Varghese et al; 2016 (30) who advised and preferred extraction of all first or maxillary first and mandibular second premolars in cases with normal Bolton's overall ratios to decrease the effect of various premolar extractions on Bolton's overall ratios.…”

Bolton ratio in subjects with normal occlusion and malocclusion

“…Although several studies 3,[9][10][11][12][13][14][15][16][17] investigated the difference in the incidence of the Bolton discrepancy between genders, there are still conflicting results in the literature. Another relevant question is the relationship between the Bolton ratio and the various types of malocclusion 1,7,12,[14][15][16][17][18] .…”

“…Although several studies 3,[9][10][11][12][13][14][15][16][17] investigated the difference in the incidence of the Bolton discrepancy between genders, there are still conflicting results in the literature. Another relevant question is the relationship between the Bolton ratio and the various types of malocclusion 1,7,12,[14][15][16][17][18] . Again, although there is evidence in the literature 11,12,[15][16][17]19,20 on the prevalence of the Bolton discrepancy in diverse populations, there is no consensus about its relationship with the different types of malocclusions classified by Angle.…”

“…Another relevant question is the relationship between the Bolton ratio and the various types of malocclusion 1,7,12,[14][15][16][17][18] . Again, although there is evidence in the literature 11,12,[15][16][17]19,20 on the prevalence of the Bolton discrepancy in diverse populations, there is no consensus about its relationship with the different types of malocclusions classified by Angle. Given the importance of these topics, this study aimed to evaluate the presence of the Bolton anterior and total discrepancy in individuals with natural normal occlusion, Class I and Class II, division 1 malocclusions.…”

The Effect of Premolar Extraction on Overall Bolton Ratio in Class III Malocclusion in RSGMP FKG USU

“…In the case of space discrepancy, one of the usual treatment options is tooth extraction, especially premolar teeth to achieve appropriate dental alignment, angulation, and inclination [14]. However, the determination of treatment options is one of the most difficult and critical for orthodontists when preparing a treatment plan [15][16][17].…”