Correlation among different profile planes used to evaluate lower lip position

ABSTRACT

The objective of this study was to correlate the soft tissue profile planes proposed by Rickett [Eline], Steiner [S-line], Burstone [B-line], and Holdaway [H-line] used to determine the lower lip position. Pretreatment cephalograms of 150 patients [age 16.2 +/- 4.1 years] were evaluated. Lower lip [labrale inferiorus] position was measured relative to Rickett's E-line, Steiner's S-line, Burstone's B-line and Holdaway's H-line. Pearson correlation was used to determine the degree of correlation between the lower lip positions determined by the four reference planes. All the pairs of variables showed statistically significant correlation [p<0.01]. Strong correlation was found between E-line and S-line [0.868], and between S-line and B-line [0.733]. Rest of the pairs showed moderate to weak correlations. H-line showed weak correlations with rest of the reference lines. This study found little difference in validity among Ricketts E-line, the Steiners S-line or Burstone's B-line. Holdaway's H-line may be used in conjunction with these reference planes