Quantifying increased rates of erosive tooth wear progression in the early permanent dentition

Objectives: To investigate if quantitative analysis of intraoral scans of study models can identify erosive tooth wear progression. Methods: Data were collected from a retrospective longitudinal study, using pre-and post-orthodontic treatment casts of 11 - 13 year olds, recorded M two consecutive appointments 29 months apart. Casts were digitised with intra-oral scanner TRIOS (TM) (3Shape, Copenhagen, Denmark) and first molar scan pairs used for analysis. Occlusal surfaces of each molar pair were visually assessed using the BEWE index as having no BEWE progression (n = 42) or BEWE progression (n = 54). Scan pairs were aligned and analysed for volume loss, maximum profile loss and mean profile loss in WearCompare (Leedsdigitaldentistry.com/wearcompare) using previously published protocols. Data were analysed in SPSS and not normal. Mann-Whitney U test with a Bonferroni correction assessed differences between progression groups. Receiver-operating-characteristic (ROC) curves were used to identify the sensitivity and specificity of quantified wear progression rates M determining visual wear progression. Results: Surfaces with visible progression demonstrated a median volume loss of -2.19 mm(3) (IQR-3.65, -0.91) compared to a median volume loss of -0.37 mm(3) (IQR -1.02, 0.16) in the no visible progression group (p < 0.001). Mean profile loss was -75.2 mu m (IQR-93.9, -61.0) and 63.2 mu m (IQR -82.5, -49.7) for the progression and no-progression groups respectively (p = 0.018). Volume loss of -1.22mm(3) represented a 79 % sensitivity and 61 % specificity. The estimated area under the curve for volume loss was 0.80 (95 %CI 0.71-0.89, p < 0.001). Conclusions: This is the first study to propose rates of high wear progression in adolescents. Limited sensitivity and specificity confirms that quantitative analysis is an adjunct tool to be used alongside history taking and clinical judgement. Clinical Significance: The rapid advancement of digital technologies may result in improved diagnosis in erosive tooth wear (ETW). Intra-oral scans and registration software are a promising adjunct for monitoring ETW progression in clinical practice.