Qualitative and Quantitative Measuring and Monitoring

Once detected and diagnosed, the severity and extent of an erosive tooth wear must be recorded to establish the clinical baseline, so that progression can be detected. Longitudinal monitoring of the erosive process would enable the outcomes of the preventive and therapeutic strategies to be assessed either qualitatively or quantitatively at the recall and review visits. There are several qualitative and quantitative ways to measure and monitor ETW in clinical practice. The established techniques include, but are not limited to:

Basic Erosive Wear Examination (BEWE): This is a management-based index in which the severity level of a lesion is scored on a four-grade level based on its extent on the tooth surface; (0) No erosive tooth wear, (1) Initial loss of surface texture, (2) Distinct defect, hard tissue loss <50% of the surface area, and may involve dentin, (3) Hard tissue loss ≥50% of the surface area, and may involve dentin.^26,49 In BEWE, the dentition is divided into sextant and the buccal, occlusal and lingual surfaces of every tooth in each sextant is examined for ETW, awarded a score value between 0 and 3, and the highest score in each sextant is recorded. The sum of the scores from the sextants constitutes the BEWE score for the patient. The BEWE for can be used to determine the ETW risk status of the patient and the clinical management, and for longitudinal monitoring of the lesion progress. ^26,49 This has the problem of inability to detect slight change in lesion severity, particularly if the progression is in depth and not in area of the lesion.

Intraoral scanners (IOS): The recent advances of digital dentistry, with the development of high-resolution tools for 3D dental imaging, and their growing access to dental practitioners have created opportunities for enhancing the detection and differentiation of dental hard-tissue conditions, including ETW lesions.⁵⁰ IOS can generate high-resolution 3D digital images of the teeth, including morphological features and photographic (colored) images. IOS can be used to capture 3D digital dental images of the teeth and then use BEWE to perform ETW assessments on the generated images.⁵⁰ This also has the problem of inability to detect slight change in lesion severity, particularly if the progression is in depth and not in area of the lesion.

Tooth Wear Index (TWI): The TWI records the degree of wear on all visible surfaces of each tooth. The severity of an erosive lesion is scored by estimating the percentage of the entire surface affected by the condition and by whether dentine is exposed or not. Unlike the BEWE, the scores from all tooth surfaces are recorded, and as such it is useful for detection and longitudinal monitoring of erosive lesion.

Silicone Matrix: This is a simple and more reliable objective and quantitative clinical method of monitoring the progression status of an erosive lesion over time. With this system, a silicone putty impression of the teeth is taken, when removed from the tray, and get sliced into sections through the centers of the erosive lesions. When a section is replaced on tooth surface, it is a perfect fit to the tooth surface, if the erosive lesion progresses, on the next review visit a gap will become visible between the silicone and the lesion surface, and the depth of the gap can be measured in millimeters (mm) using the calibrated periodontal probe (explorer). If no gap, then the lesion is arrested.⁴⁹

Clinical photographs: Clinical photographs are simple useful, but subjective, method of monitoring erosive tooth wear. However, the dexterity of the photographer and the ambient conditions such as light reflections affect the quality of the product.⁴⁹