Age-related Changes on canal wall thicknesses in Maxillary First Premolar

Objectives: The aim of this study was to explore root canal wall widths at various ages in the maxillary first premolar. Methods: 40 maxillary first premolars were divided into four groups as follows: Group A: aged 10~16,Group B: aged 20~39,Group C: aged 40~59,Group D: aged over 60. Each tooth was scanned, employing micro-computed tomography (µ-CT) at a resolution of 0.08mm. Root canal wall thicknesses of each tooth were measured by MIMICS8.0. ANOVA three-way analysis with repeated measures was used to analyze all data and establish statistical significance for the following parameter: aged(group A,B,C,D), aspect of tooth surface(B,L,M,D,MB,DB,ML,DL), root level(coronal, middle, apical ). Results: The maximum width of the root canal wall was 1.735mm, and the minimum was 0.454mm. The wall thicknesses were increasing from group A to group C(P<0.05), but did not changed from group C to group D(P>0.05).There is no statistical difference in the wall thicknesses between the MB and L, ML and DB, M and D areas of the root(P>0.05), and there is statistical difference among others areas(P<0.05). The wall thicknesses were thinner in the apical third than the middle third and coronal third. Conclusion: The wall thicknesses of maxillary first premolar were greatest in the age 40~59 group. The sequence of the wall thicknesses of tooth aspect: MB,L>B>ML,DB>DL>M,D. The wall thicknesses were thinnest in the apical third, gradually increasing from the apical third to the coronal third.