Measurement of Base of Contact to CEJ in Skulls

Objectives: The extent of periodontal disease progress is measured using the distance of CEJ to the base of the pocket to obtain the attachment loss.  This measurement involves measurement of the distance from the gingival margin to the depth of the pocket and then measuring the distance from the gingival margin to the CEJ.  The CEJ is the key landmark in determining periodontal disease progression; however there are often problems in locating this key landmark for both students and experienced clinicians.  The objective of this study is to propose an alternative landmark to estimate the CEJ which is more visible and less prone to subjectivity of the operator.

Methods: The distance from the base of the normal contact to the CEJ was measured using a digital micrometer on 186 sites in 6 skulls.

Results: The mean distance from the base of the normal interproximal contact to the CEJ on all teeth, except maxillary incisors, was 3.06 mm with a SD of ±0.81. The corresponding distance on the maxillary incisors was 4.03 mm with a SD of ±0.87 and the difference between maxillary centrals and the rest of the teeth was significant (P<0 .0001).

Conclusion: The distance from the base of the normal contact to the CEJ is 3 mm for teeth other than maxillary incisors and 4 mm for maxillary incisors. This was a consistent finding. This leads to the possibility that this may prove to be a repeatable, reliable, and alternative means of relating the gingival margin to the CEJ which does not depend on the tactile sensitivity needed to locate a subgingival landmark or one that is potentially obscured by a restoration or calculus.