THE USE OF 3D VIRTUAL PLANNING AND 3D PRINTING FOR THE TREATMENT OF FACIAL ASYMMETRY : A CASE REPORT
3 . Results The visual evaluation of the simulated and actual extensions revealed a good approximate in terms of shape and position . For the quantitative analysis , at the bone level via the part comparison , revealed a mean of 0.29 mm and standard deviation of 1.73 mm . Figure 6 shows the results of the part comparison with the simulated extension overlaid
on the postoperative extension and the color coded map ranging in mm . Extreme differences ( 5 mm ) were found at the region of mandibular angle while differences at the mandibular body region ranged between 0 and 3 mm . Figure 8 shows the extra-oral clinical images taken for this patient preoperatively ( left ) and 6 months postoperatively ( right ).
Figure 6 . Color coded map for the part comparison analysis between the simulated and actual extensions
4 . Discussion In this study we presented a case with facial mandibular asymmetry . As the patient ’ s complaints and diagnosis were only esthetic with no functional problems , the recommended treatment was autogenous apposition bone graft . Even though other non-resorbable graft materials could equally be used by the same method , the patient opted for an autogenous graft material . The use of 3D planning and printing was investigated where the mirroring technique around the midsagittal plane was applied to simulate the symmetry of the mandible both sides . A 3D printed extension was used during the surgery as a guide for harvesting
and grafting for accurate positioning . For the quantitative postoperative evaluation for the bone in relation to the simulation revealed mean error of 0.29 mm (± 1.73 mm ). Maximum differences were found at the mandibular angle part . This can be due to the difficulty of reshaping the bone in this region . Since it is recommended to evaluate the soft tissue minimum 6 months postoperatively ( 7 ), quantitative evaluation one month postoperatively was not possible , but visually it was in line with the preoperative prediction ( Fig . 7 ).
a . b . c .
d . e .
Figure 7 . a . Preoperative soft tissue . b . Soft tissue simulation after mirroring procedure from right to left . c . One month postoperative soft tissue . d . Soft tissue postoperative ( gray ) superimposed on the preoperative simulation ( blue ). e . Differences between the two soft tissues in ( d ) enlarged at the operation side
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