Clinical Useability of an "Examination Scale" for Residual Ridge Assessment

Purpose: To establish a simple and objective assessment of the residual ridge height and shape of edentulous patients, clinical useability of a newly developed "examination scale" based on our clinical research was investigated.

Methods: The right and left first molars sections of 30 subjects (10 males, 20 females, average age:79) with edentulous maxillas and mandibles were evaluated. Subjective evaluation and evaluation using an "examination scale" were carried out by 3 dentists. Objective evaluation was performed with digital vernier calipers on study models. The "examination scale" was designed with four grades (U, middle, V, flat) for residual ridge shape and three grades (high, middle, low) for residual ridge height. Agreement among subjective evaluation, objective evaluation, and the "examination scale" were examined with kappa statistics.

Results: Marked variations were noted between the subjective evaluation and the objective evaluation regardless of the individual. Agreement between the subjective evaluation and the objective evaluation showed low kappa values (height: maxillas: 0.35, mandibles: 0.53, shape: maxillas: 0.44, mandibles: 0.43). However, relatively low variations were noted between the "examination scale" and the objective evaluation, and the correlation between the "examination scale" and the objective evaluation was high with high kappa values (height: maxillas: 0.81, mandibles: 0.66, shape: maxillas: 0.88, mandibles: 0.72).

Conclusion: Our newly developed "examination scale" for residual ridge height and shape of edentulous patients correlated significantly with an objective evaluation, indicating high clinical useability of this scale.