Assessment of the Residual Ridge Shape of Edentulous Patients

Methods: The right and left first molar regions in study models (100 sets) of edentulous maxillas and mandibles were evaluated. Subjective assessment with four-grade (U shaped, U-V shaped, V shaped, flat) scale was performed by 16 dentists and objective measurement (the breadth of the residual ridge at 3 mm height in maxillas and 2 mm height in mandibles ) was measured with digital vernier calipers. The relationship between subjective assessment and objective assessment was studied separately in dentists with less than 3 years of clinical experience and those with more than 7 years. Discrimination values for objective assessment were determined at changeover points of the rate of subjective assessment. In addition, agreement between subjective assessment and objective assessment was studied with the discrimination values.

Results: Marked variation was noted in subjective assessment depending on the individual and number of years of clinical experience. Discrimination values were obtained from subjective assessment by more than 7 years of clinical experience: for the maxilla, “ V ” and ” U-V ” ; 7 mm and “ U-V ” and “ U ” ; 9 mm, for the mandible, “ V ” and “ U-V “ ; 5 mm and “ U-V “ and “ U “ were 7 mm. Agreement between subjective assessment and objective assessment based on these discrimination values was extremely low regardless of the individual's clinical experience.

Conclusion: Reproducibility of subjective assessment of the residual ridge shape was low. To improve the universality and reproducibility of the examination, subjective assessment must be performed with the discrimination values as references.