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Journal of Oral Science & Rehabilitation Volume 2 | Issue 3/2016 23 H a r d - a n d s o f t - t i s s u e c h a n g e s w i t h a s u p e r i m p o s i t i o n t e c h n i q u e year after delivery of the definitive restorations, no complications were observed (fracture, wear, chipping or debonding). Mean soft-tissue levels improved between bonding and the one-year follow-up examination. The mean height of the mesial and distal papillary changes was 0.64 ± 0.31 and 0.47 ± 0.28, respectively. Discussion The present clinical study examined a new ob- jective technique to assess the hard- and soft- tissue changes in natural and artificial dentition. The present technique is not intended to replace previously established methods developed to evaluate the esthetic success of a dental treat- ment. Conversely, the superimposition of CAD model casts may complement techniques that use subjective methods, such as standardized clinical photographs. The main limitation of the present technique is the spatial resolution of the scanners and that it does not evaluate color. Nevertheless, the study cast evaluation involved a PES/WES evaluation,facilitatingthe objective appreciation ofcrown outline, aswellas hard- and soft-tissue changes. Esthetics are subjective and linked to the patient, but this technique aims to evaluate thethicknessandlevelofthehardandsofttissue, which is also useful in pre- and postoperative comparison(e.g.,bonereconstructionandsocket preservation). The results of the present study showed a mean soft-tissue increase atthe levelofboththe mesial and distal papillae between the pre- and post-treatment situations. A possible explan- ationcouldbethere-establishmentofthecorrect contact points and the renewed instructions on proper oral hygiene. All of the reference studies5–7 use subjective indexes and require the capture of a series of photographstocomparethedifferencesbetween follow-up examinations. If clinical photographs are to provide an accurate record of pre- and postoperative patient appearance, the relative positions ofthe patient and camera must be kept constant. Perspective distortion may be an un- acceptable drawback, especially in comparison ofpre-andpost-treatmentclinicalphotographs.19 CBCT scanning ensures a comprehensive, high-precision scan of both impressions and plaster casts, delivering accurate 3-D models, which can be used immediately or stored for lateruse.The scanned 3-D modelcan be export- ed as a DICOM set or superimposed onto CBCT data to provide an artifact-free model of the patient’s dentition, including the bone, crowns and soft tissue. The DICOM and STLfiles can be superimposed too, helping the clinician with clinicalandtreatment planning, aswellas allow- ing for pre- and post-treatment comparison. A straightforward DICOM to STL conversion is easily possible. Conoscopic holographyscanningtechnology is a valid option for the laboratory digitization of model casts.20 This technology projects and re- flects light beams from the shape of a complex scanned object along the same linear pathway. This collinearitymeasures steep angles and deep cavities for precision scanning. Furthermore, it allows, in a few minutes, a full simultaneous digitization of a model cast in a single work session without any manual user intervention. Figs. 6a & b a b Figs. 6a & b Corresponding points in the DICOM (a) and STL (b) data during superimposition. Volume 2 | Issue 3/201623