In vitro evaluation of the effects of different particle types in toothpastes on the efficacy against enamel erosion and wear.

The effects of the particle fraction in toothpastes in the context of erosion and erosive tooth wear has not been fully elucidated. Thus, aim of this study was to investigate experimental toothpastes, each with one specific particle type. Toothpastes with seven different types of silica or alumina were prepared as slurry either with or without active ingredients (NaF or F/Sn). Human enamel samples were exposed to a cyclic erosion/abrasion model, and were either treated with the respective slurries only or additionally brushed in a brushing machine. Tissue loss was profilometrically monitored. After treatment with slurries without active ingredients or with NaF, tissue loss increased significantly within groups over time (p < 0.001 each). At the end of the trial, there were minor differences between groups (not exceeding 10-20%; p > 0.05 for most comparisons). After treatment with the F/Sn slurries, tissue loss stagnated completely over time, with the exception of one silica type and alumina, but both still reduced tissue loss by 40-50% (compared to control p < 0.001 each). Relative to the type of the active ingredient, the particle type seems to be a secondary factor for the efficacy of toothpastes on erosion and erosive tooth wear in enamel.

Visualization of dental plaque with a 3D-intraoral-scanner-A tool for whole mouth planimetry.

Planimetry is a reliable method for detecting and monitoring plaque. Until now, this method has mainly been applied to conventional-camera images, which is difficult and time-consuming in relation to the entire dentition. Today, 3D-intraoral-scans are well suited for imaging the entire dentition and are therefore an efficient and feasible alternative. 3D-intraoral-scans have already proven successful for the quantification of plaque based on a plaque index. Therefore, aim of this study was to investigate whether images from 3D-intraoral-scans are also suitable for valid planimetric plaque measurements and monitoring; intraoral-camera images served as a reference. Twenty subjects (27.5±1.2 years) were included. Plaque was disclosed at three different time points: habitual plaque (T1), after 72 h without oral hygiene (T2) and after subsequent tooth brushing (T3) and quantified using 3D-intraoral-scans and intraoral-camera images (intraoral-camera CS 1500, intraoral-scanner CS 3600; Carestream Dental, Germany). The percentage of the plaque-covered surface of the total surface area (P%) was determined with a software specially programmed for this purpose using images from 3D-intraoral-scans of the oral and vestibular surfaces of the Ramfjord teeth (16, 21, 24, 36, 41, and 44); the intraoral-camera images of the vestibular surfaces of 16 and 36 served as reference. P% from images of the 3D-intraoral-scan and the intraoral-camera revealed a very good correlation (r = 0.876; p ≤ 0.001); the Bland-Altmann analysis showed a good agreement with no proportional and a very minor systematic bias with slightly higher values from images of the 3D-intraoral-scan. Further, P% measurements of the images of the 3D-intraoral-scan were able to detect changes in plaque levels, showing a 47% (p ≤ 0.001) increase in P% from T1 to T2 and a 43% (p ≤ 0.001) decrease after toothbrushing (T3). Planimetry using images of the 3D-intraoral-scan seems to be a suitable tool for whole mouth planimetry to record and monitor dental plaque.