METHODS: 71 investigation sites of sound fissure and naturally occurring NCFC on human extracted premolars were identified and scanned with a swept-source OCT. The teeth were then sectioned bucco-lingually at the investigation sites and imaged using PLM. Two calibrated examiners trained on the B-scan NCFC visual interpretation criteria established for this study, assessed the investigation sites and results were validated against PLM.

RESULTS: Detection sensitivity of B-scan for NCFC when fissures were assessed in totality, or on the slopes or walls separately are 0.98, 0.95, 0.94 and specificity are 0.95, 0.90, and 0.95. One-way ANOVA showed that width measurements of wall loci done with OCT and PLM were not statistically different. However, OCT height measurements of slope loci were statistically bigger with a constant bias of 0.08 mm (of which is not clinically significant) and OCT height measurements of wall loci were statistically smaller (0.57 mm) and Bland-Altman plots indicated presence of proportionate bias.

CONCLUSION: Visual assessment of B-scans with the interpretation criteria resulted in both high specificity and sensitivity and were not affected by loci location. OCT width measurement of wall loci is in agreement with PLM.

MATERIALS AND METHODS: This quality improvement project was undertaken at a private university. Guided by the PDSA model, rubber dam application tasks were conducted in the simulation lab in 2 phases. Phase 1 included TBSL and phase 2 included EBSL comprising of 2 PDSA cycles. 'Plan' stage involved obtaining feedback from students and the concerned staff. 'Do' stage included implementation of EBSL in eight steps adopted from Higgins's framework. 'Study' stage evaluated the outcomes and in 'Act' stage amendments were made to the first EBSL cycle. In the second PDSA cycle re-implementation and evaluation of the rubber dam application exercises were carried out. Descriptive data were presented as percentages and mean scores were compared using paired t-test.