Periodontal assessment by right- and left-handed examiners: is there a difference?

Multiple factors that influence the precision of periodontal probing measurements have been identified. These factors can be categorized as being dependent upon host-related, probe-related, or examiner-related variables. However, the potential influence of examiner handedness (right or left) on the measurement of periodontal probing depths (PDs) has not been addressed. The purpose of this study was to determine whether the measurements of PDs in the right and left quadrants are influenced by the handedness of the examiner.

Eight systemically healthy adult subjects with varying degrees of attachment loss and a minimum of 20 teeth were examined by five right-handed and five left-handed clinicians. The 10 clinicians were trained and calibrated for reproducible probe placement and angulation. PDs were measured using a conventional periodontal probe at six sites per tooth. Mean PD measurements were compared between right- and left-handed examiners using analysis of variance (ANOVA) with a random patient effect to correlate participant data and a random effect for the examiner.

There was no statistical difference in the measurement of PDs between right- and left-handed examiners at various locations in the mouth (P>0.17 in all cases). Only three individual sites showed a statistically significantly different mean PD between right- and left-handed examiners (unadjusted P<0.05; differences at or near 0.5 mm). Overall, right-handed examiners tended to record slightly higher PD measurements than left-handed examiners, but this difference did not reach statistical significance.

The handedness of the periodontal examiner does not appear to influence the recorded measurement of probing depths. This finding is relevant to those conducting clinical research involving assessment of periodontal status.