Mandibular rehabilitation: From the Andy Gump deformity to jaw-in-a-day

Bone reconstruction using CAD/CAM technology in head and neck surgical oncology. A narrative review of state of the art and aesthetic-functional outcomes

Bone defects following resections for head and neck tumours can cause significant functional and aesthetic defects. The choice of the optimal reconstructive method depends on several factors such as the size of the defect, location of the tumour, patient’s health and surgeon’s experience. The reconstructive gold standard is today represented by revascularised osteo-myocutaneous or osteomuscular flaps with osteosynthesis using titanium plates. Commonly used donor sites are the fibula, iliac crest, and lateral scapula/scapular angle. In recent years, computer-aided design (CAD)/computer assisted manufacturing (CAM) systems have revolutionised the reconstructive field, with the introduction of stereolithographic models, followed by virtual planning software and 3D printing of plates and prostheses. This technology has demonstrated excellent reliability in terms of accuracy, precision and predictability, leading to better operative outcomes, reduced surgical times and decreased complication rates. Among the disadvantages are high costs, implementation times and poor planning adaptability. These problems are finding a partial solution in the development of “in house” laboratories for planning and 3D printing. Strong indications for the use of CAD/CAM technologies today are the reconstruction of total or subtotal mandibular or maxillary defects and secondary bone reconstructions.

[Clinical analysis of denture rehabilitation after mandibular fibula free-flap reconstruction]

OBJECTIVE

To evaluate the postoperative denture restoration and denture function in patients with mandibular defect reconstructed with vascularized free fibula flap.

METHODS

In the study, 154 patients who underwent mandibular segment resection and used vascularized free fibula flap to repair mandibular defects due to inflammation, trauma and tumor from January 2015 to December 2020 were collected. These patients had common inclusion criteria which were stable occlusal relationship before operation, segmental defects of mandibular bone caused by lesions of mandible and adjacent parts (such as floor of mouth, tongue, cheek), free fibula flap used for repair and surviving after operation. Relevant data were reviewed and situation of denture restoration was followed up. A questionnaire related to denture functional evaluation had been proposed for those who had completed the denture rehabilitation. The evaluation index of denture restoration function was assigned by expert authority to obtain the denture function score. SPSS 18.0 software was used for statistical analysis of the basic information of the patients included in the study and the denture restoration of the patients.

RESULTS

The rate of postoperative denture restoration in the patients with mandibular defects repaired by free fibula flap was 17.5%, and the rate of postoperative denture restoration in the patients with benign mandibular tumors was 25.0% (18/72), which was significantly greater than that in the patients with malignant tumors 11.0% (9/82, P < 0.05). There was no significant difference in denture function score between the patients with condylar defect and those without condylar defect in denture repair rate and denture function score (P>0.05). The functional score of implant denture was significantly greater than that of removable denture (P < 0.05). According to Brown classification, the denture function score of the patients with the defect invo-lving the anterior mandibular region was significantly greater than that of the patients without the anterior mandibular region involved (P < 0.05). The poor oral conditions, such as less amount of remaining teeth, insufficient retention strength, large mobility of soft tissue in the surgical area, poor oral vestibular groove condition became the main reason of not receiving denture restoration (37.86%).

CONCLUSION

The denture rehabilitation of mandibular defect reconstructed with vascularized free fibula flap is closely rela-ted to pathological properties and oral conditions. The clinical outcome of implant denture has been confirmed effectively and it is a better choice for future denture restoration after mandibular reconstruction.

The role of computer aided design/computer assisted manufacturing (CAD/CAM) and 3- dimensional printing in head and neck oncologic surgery: A review and future directions

Microvascular free flap reconstruction has remained the standard of care in reconstruction of large tissue defects following ablative head and neck oncologic surgery, especially for bony structures. Computer aided design/computer assisted manufacturing (CAD/CAM) and 3-dimensionally (3D) printed models and devices offer novel solutions for reconstruction of bony defects. Conventional free hand techniques have been enhanced using 3D printed anatomic models for reference and pre-bending of titanium reconstructive plates, which has dramatically improved intraoperative and microvascular ischemia times. Improvements led to current state of the art uses which include full virtual planning (VP), 3D printed osteotomy guides, and patient specific reconstructive plates, with advanced options incorporating dental rehabilitation and titanium bone replacements into the primary surgical plan through use of these tools. Limitations such as high costs and delays in device manufacturing may be mitigated with in house software and workflows. Future innovations still in development include printing custom prosthetics, 'bioprinting' of tissue engineered scaffolds, integration of therapeutic implants, and other possibilities as this technology continues to rapidly advance. This review summarizes the literature and serves as a summary guide to the historic, current, advanced, and future possibilities of 3D printing within head and neck oncologic surgery and bony reconstruction. This review serves as a summary guide to the historic, current, advanced, and future roles of CAD/CAM and 3D printing within the field of head and neck oncologic surgery and bony reconstruction.

Osteocutaneous Radial Forearm Free Flap Fixed to a Prior Osteocutaneous Free Flap: Two Case Reports

Reconstruction of mandibular defects is best accomplished by composite bony tissue. When the fibula is not available other sources must be used. Occasionaly tumor recurence will neccesitate a further resection and bony reconstruction. We report two cases in which osteocutaneous radial forearm free tissue transfer was used for secondary reconstructio after prior bony free flap reconstruction. Laryngoscope, 2022.