Analysis of the effects of mandibular reconstruction based on microvascular free flaps after oncological resections in 21 patients, using 3D planning, surgical templates and individual implants.

INTRODUCTION: Post- resection defects in the area of the head and neck frequently result in functional impairment of the masticatory system and unaesthetic outcome in the facial appearance. In pediatric population they exert a devastating effect on speech development, breathing and facial growth leading to secondary deformations which are extremely challenging in reconstruction by means of conventional surgery protocols. MATERIAL AND METHODS: 21 patients (14 males/ 7 females) aged 4-17 years old, treated between 2015 and 2019 due to malignant/benign tumors or congenital deformities requiring mandible resection were enrolled in the study. All patients underwent Virtual Surgical Planning (VSP), mandible tumor resection with use surgery guides and defect reconstruction with microvascular bone graft supported with custom implants. Postoperatively, 3D models used for the planning and postoperative 3D model of the reconstructed mandible were compared using authors method based on easily measurable morphometric measurements (3 angles, 3 linear dimensions), allowing a three-dimensional quantitative assessment of postoperative outcomes of the surgery. Linear regression analysis and one-way analysis of variance were used to evaluate the clinical material. The difference was considered significant if p < 0.05. RESULTS: Free fibula flap (FFF) was most commonly used type of the reconstruction of the pediatric mandible. The average maximum deviation for the analyzed cases was 7.7 mm, and the average minimum deviation was -6.09 mm, however without significant differences and the postoperative position of the mandible condyle was comparable to the position designed in the 3DVSP preoperatively. Position of the whole reconstructed mandible by means of individually planned grafts and plates provided comparable position of the ramus and mandible body and no chin deviation as the differences between the pre-operative axial and sagittal angles and their post-operative equivalents were insignificant (p > 0,05). CONCLUSIONS: This study confirms applicability of the 3DVSP in pediatric craniomaxillofacial surgery. Preoperative planning of the osteotomies, grafting technique and production of the individualized guides and implants provides precise tumor resection and immediate reconstruction adjusted to the specific anatomy of the pediatric patients.

Protocol for Multi-Stage Treatment of Temporomandibular Joint Ankylosis in Children and Adolescents.

Treatment of temporomandibular ankylosis is challenging and frequently leads to re-ankylosis, relapse, dangerous complications and, in turn, the need for multiple operations. In this article, we present a protocol for the treatment of ankylosis of the temporomandibular joints that assumes earlier intervention with the assistance of 3D virtual surgical planning (3DVSP) and custom biomaterials for better and safer surgical outcomes. Thirty-three patients were treated due to either uni- or bilateral temporomandibular ankylosis. Twenty individuals received temporomandibular prosthesis, whereas seventeen required simultaneous 3D virtual surgical/planned orthognathic surgery as the final correction of the malocclusion. All patients exhibited statistically significant improvements in mouth opening (from 1.21 ± 0.74 cm to 3.77 ± 0.46 cm) and increased physiological functioning of the mandible. Gap arthroplasty and aggressive rehabilitation prior to temporomandibular prosthesis (TMJP) placement were preferred over costochondral autografts. The use of 3DVSP and custom biomaterials enables more precise, efficient and safe procedures to be performed in the paediatric and adolescent population requiring treatment for temporomandibular ankylosis.

Protocol and Evaluation of 3D-Planned Microsurgical and Dental Implant Reconstruction of Maxillary Cleft Critical Size Defects in Adolescents and Young Adults.

Functional and esthetic final reconstruction of the cleft maxilla is still challenging. Current reconstructive and augmentation techniques do not provide sufficient bone and soft tissue support for the predictable rehabilitation with dental implants due to presence of maxillary bone critical size defects and soft tissue deficiency, scaring and poor vascularity. In this article the protocol for the use of 3D virtual surgical planning and microvascular tissue transfers for the reconstruction and rehabilitation of cleft maxilla is presented. Twenty-five patients (8 male/17 female) aged 14-41 years old with cleft-associated critical size defects were treated by 3D-virtual planned microvascular tissue transfers taken either from fibula, iliac crest, radial forearm, or medial femoral condyle. Follow-up lasted 1-5 years. No significant bone resorption (p > 0.005) nor volume loss of the graft was observed (p = 0.645). Patients received final permanent prosthetic reconstruction of the anterior maxilla based on 2-5 dental implants, depending on the defect severity. This is the first study presenting the use of virtual planning in the final restoration of the cleft maxilla with microvascular tissue transfers and dental implants. Presented protocol provide highly functional and aesthetic results.