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A new method for volumetric evaluation of gingival recessions: a feasibility study.

BACKGROUND
This preliminary in vitro study, presented at the General Session of the International and American Association for Dental Research in 2010 (Barcelona, Spain), evaluates whether three-dimensional (3D) optical scanning and subsequent superimposing procedures could be used for reproducible volumetric evaluation of gingival recession.


METHODS
Silicone impressions were taken of mandibular and maxillary master casts, and eight stone replicas of each master cast were produced. Each replica was scanned 10 times with a 3D optical system, and 3D datasets representing the computer-aided design reference models were calculated using a triangulation method. Marks designating gingival recession were scratched into the anterior segments of the replicas. The modified replicas were then scanned 10 times, and 3D datasets were calculated and subsequently superimposed. Differences in the volume of the gingival recession were recorded with reference to the initial data.


RESULTS
The determination of gingival recession volume was highly reproducible. For all replicas, the 3D optical method showed small standard deviations and intraclass correlation coefficients between 0.997 and 0.999.


CONCLUSIONS
This new method allows the reproducible volumetric evaluation of gingival recession marks on stone replicas. Additional clinical trials are necessary to confirm these in vitro findings. This method allows the operator to control the volumetric progression of periodontal soft tissue, for example, after root coverage procedures and to detect relapses at an early stage.