Monitoring erosive tooth wear with intraoral 3D scanner: A feasibility study

Purpose: To evaluate in vitro the potential of an intraoral scanner (IOS) to monitor erosive tooth wear (ETW) using different alignment software with distinct quantitative measurement metrics. Methods: 15 unpolished bovine crowns were exposed to citric acid (pH ∼2.5) at 24-hour intervals up to 168 hours. At baseline and after each acid exposure episode, the teeth were scanned with IOS (3 Shape TRIOS 3). Scanned images from each data point were superimposed on baseline image using WearCompare software to obtain volume loss (mm³) and area loss (mm²) and using IOS built-in software (3Shape TRIOS Patient Monitoring) to obtain depth loss (mm). Pearson's test was used to determine the correlation between acid exposure time (h) and each outcome measure (α= 0.05). Results: As the acid exposure time increased, the lesion parameters (depth, volume, and area) increased. Friedman's test showed that relative to baseline volume loss became significant (P< 0.05) after 72 hours from median 11.48 mm³(IQI 25% = 8.72 mm³), eroded area became significant (P< 0.05) from median 48.67 mm²(IQI 25% = 44.46 mm², P< 0.05) after 96 hours, and erosion depth became significant (P< 0.05) from median 0.69 mm (IQI 25% = 0.66 mm²) after 144 hours. A strong correlation was observed between depth (mm²) and time (r= 0.9993 P< 0.0001), volume (mm3) and time (r= 0.9968, P< 0.0001), and area (mm²) and time (r= 0.9475, P= 0.0003).