Assessment of gingival thickness using digital file superimposition versus direct clinical measurements

This study was aimed at evaluating the correlation and reproducibility of gingival thickness quantification using digital and direct clinical assessment methods.

Patients in need of tooth extraction were allocated into two groups according to the gingival thickness measurement method, either using an endodontic spreader (pre-extraction) or a spring caliper (post-extraction), both on the mid-facial (FGT) and mid-lingual (LGT). Pre-extraction Digital Imaging and COmmunications in Medicine (DICOM) and STereoLithography (STL) files of the arch of interest were obtained and merged for corresponding digital measurements. Inter-rater reliability between digital and direct assessment methods was analyzed using inter-class correlation coefficients (ICC).

Excellent inter-rater reliability agreement was demonstrated for all parameters. Comparison between the endodontic spreader and the digital method revealed excellent agreement, with ICC of 0.79 (95% CI 0.55, 0.91) for FGT and 0.87 (95% CI 0.69, 0.94) for LGT, and mean differences of 0.08 (- 0.04 to 0.55) and 0.25 (- 0.30 to 0.81) mm for FGT and LGT, respectively. Meanwhile, the comparison between the caliper and the digital method demonstrated poor agreement, with ICC of 0.38 (95% CI - 0.06, 0.70) for FGT and 0.45 (95% CI - 0.02, 0.74) for LGT, and mean differences of 0.65 (0.14 to 1.16) and 0.64 (0.12 to 1.17) mm for FGT and LGT, respectively.

Digital measurement of gingival thickness is comparable with direct clinical assessments performed with transgingival horizontal probing using an endodontic spreader.

Digital assessment of gingival thickness is a non-tissue invasive, reliable, and reproducible method that could be utilized as an alternative to horizontal transgingival probing.