VIRTUAL PLANNING OF MANDIBLE DEFECTS SECONDARY RECONSTRUCTION IN KROKODIL DRUG-ADDICTED PATIENTS

Background: Treatment for stage 3 cases of mandible ONJ involves segmental resection, with or without TMJ
exarticulation. These cases result in large continuity defects of the mandible. Primary reconstruction of such defects
carries a high risk of disease recurrence. In 21,4% of stage 3 mandible ONJ cases, disease recurrence is observed after
segmental resection without primary reconstruction. For this reason, secondary reconstruction is employed in ONJ
patients. Delayed reconstruction of the mandible reduces the recurrence rate but complicates the proper alignment of
the mandible fragments in their initial anatomical position.
Aim:The aim of this study is to share our approach to using virtual surgical planning for secondary reconstruction of
the mandible, utilizing only stereolithographic models.
Materials and methods:This is a retrospective study of four patients with secondary mandibular defects due to the
resection of stage-3 Krokodil drug-related osteonecrosis. All cases were analyzed concerning complaints, age, period
of Krokodil use, Krokodil withdrawal period, and surgery outcomes. Before surgery, CBCT, orthopantomography
were performed in all cases. Then, using the CT scans, the mandible defect was reconstructed by mirroring the healthy
side. The reconstructed mandible model was printed on a 3D printer. The reconstructive plate was prebended on the
model. In all patients, the existing defects were reconstructed using only prebended reconstructive plates
Results: The postoperative follow-up period ranged from 6 to 18 months. No recurrence occurred during the
postoperative period for any patient. All patients noted good aesthetic and functional outcomes.
Conclusion: Within the limitations of the study, the use of 3D virtual planning and prebent reconstructive plates can
be an effective and predictable method for the secondary reconstruction of mandible defects using only a
reconstruction plate in Krokodil drug-addicted patients.