Evaluation of Ultrasound for Measuring Remaining Dentin Thickness: In Vitro Study

Türkiye Klinikleri Diş Hekimliği Bilimleri Dergisi, cilt.32, sa.2, ss.534-540, 2026 (TRDizin)

Objective: To determine the remaining dentin thickness

between the cavity floor and pulp tissue at 3 levels: dentino-enamel junc-

tion, 0.5 mm coronal, and 1 mm coronal to the pulp horn using ultrasonic

measurement compared with digital caliper. Material and Methods:

Twenty-one sound human molars, free of caries and restorations, were

disinfected in 0.1% thymol solution for 1 week, cleaned of tissue, and

examined under 2.5x magnification microscope. The teeth were randomly

divided into 3 groups (n=7). Vertical sections were obtained using a di-

amond-separating disc in the mesiodistal direction. Horizontal sections

were taken from the apical of the dentino-enamel junction in group 1, 1

mm coronal of the pulp horn in group 2, and 0.5 mm coronal of the pulp

horn in group 3. Measurements were taken using an ultrasonic system

(Novascope 4500, NDT, Waltham, Mass., USA; 11 MHz frekans, 1,5

mm prob, Harisonic, Staveley NDT, Wash., USA) with glycerin coupling

gel and a digital caliper (Dasqua 1804-1065, Italy). Three measurements

were obtained between the pulp horns of each sample. Paired t-tests were

used for analysis. Results: No statistically significant differences were

found between the mean values of 2 methods at any level (p>0.05). A

strong positive correlation was demonstrated between ultrasonic and

caliper measurements (r=0.872, p<0.001), with high reliability (Cron-

bach’s alpha=0.91). Conclusion: Using an ultrasonic system to measure

dentin thickness at different levels appears promising. Accurate mea-

surement of remaining dentin thickness during cavity preparation is crit-

ical for preventing pulp exposure and preserving vitality. The findings

suggest ultrasonic systems may provide a reliable, non-invasive method

for real-time monitoring of dentin thickness.