Comparison of Mechanical Stability between Fibular Free Flap Reconstruction versus Locking Mandibular Reconstruction Plate Fixation

Prosthetic rehabilitation of segmental mandibulectomy patient using a free fibula flap and Corticobasal implant supported prosthesis: A Case report

INTRODUCTION

Segmental mandibular reconstruction using free fibula flaps and implants is challenging for maxillofacial surgeons and prosthodontists. This case report describes the successful use of Corticobasal implant reconstructive prostheses after a free fibula flap with five years of follow-up.

CLINICAL CASE PRESENTATION

A 24-year-old female presented to the clinic following segmental defect reconstruction using fibula reconstruction, owing to squamous cell carcinoma resection and seeking prosthetic treatment. An intraoral examination revealed a complete healing of the soft tissue. A panoramic radiograph showed a fibula bone graft rehabilitating the left side of the mandible supporting with a reconstructive plate. A multidisciplinary team was formed. A treatment plan included a mandibular reconstructive fixed Corticobasal implant prosthesis supported by eight basal cortical screw implants (BCS®, Dr. Ihde Dental AG, Switzerland) and a follow-up schedule was formulated. After 5-years of function, the implant demonstrated a 100 % survival rate, with no implant loss or fracture, excellent peri-implant soft tissue health, complete union of the bone graft, and a very stable prosthesis. The patient reported significant improvements in aesthetics, mastication, phonation, and self-satisfaction.

DISCUSSION

The multidisciplinary team has significantly improved the treatment outcomes. The prescribed treatment modality provides the patient with a fixed treatment modality, immediate loading, reduces the risk of biological and biomechanical complications, and hence improves the patient's functions and satisfaction.

CONCLUSION

A Corticobasal implant-supported prosthesis can be used in combination with a free fibula flap to reconstruct segmental mandibulectomy patients with a high survival rate and satisfactory aesthetic and functional outcomes.

MRONJ of the Mandible—From Decortication to a Complex Jaw Reconstruction Using a CAD/CAM-Guided Bilateral Scapula Flap

Medication-related osteonecrosis of the jaw (MRONJ) has been an integral part of the maxillofacial patient population for some time. The therapeutic concept ranges from conservative approaches over less extended decortications to major jaw resections, which can result in a considerable loss of quality of life. Based on three case reports, this paper presents the long-term history of patients with MRONJ of the mandible, whose disease ultimately resulted in partial or total mandibular resection and subsequent multisegmental reconstruction using a microvascular anastomosed bone flap. Furthermore, a suitable alternative for complex mandibular reconstruction is demonstrated when using a free fibula flap is not possible. The options are limited, particularly when multisegmental restoration of mandibular continuity is required. One case presents a mandible reconstruction using a CAD/CAM-guided bilateral scapular free flap (CAD/CAM = Computer-Aided Design and Manufacturing), which has not been described for this purpose before. Due to the complexity, computer-assisted surgery and patient-specific implants seem reasonable, which is why a special focus was applied to this topic.

Outcomes of mandibular reconstruction using three-dimensional custom-made porous titanium prostheses

BACKGROUND

Our aim was to report the long-term outcomes of mandibular reconstruction using CAD-CAM-designed 3D-printed porous titanium implants in patients not amenable to a free vascularized fibula flap reconstruction.

METHODS

The implants were designed with ProPlan CMF® 2.2 software and manufactured with a Selective Laser Melting (SLM) "layer-by-layer" 3D-printing of pure porous titanium powder beds. Primary endpoints were implant exposure and implant removal calculated using Gray's tests. Secondary endpoints were predictive factors of implant exposure and implant removal, and rates of dental rehabilitation.

RESULTS

Thirty-six patients were operated between 2015 and 2017 and were included in this study. Reconstruction using a porous titanium 3D-printed implant was proposed due to medical contraindication for a fibula free flap (n = 13), due to the failure of a previous fibula free flap reconstruction (n = 7), or due to refusal of a fibula free flap reconstruction by the patient (n = 16). The medical indications for mandibular reconstruction were a primary tumor requiring mandibulectomy in nine patients, mandibular osteoradionecrosis requiring mandibulectomy in nineteen patients, and secondary reconstruction in eight patients. The 2-year rates of implant exposure and implant removal were 69.4% and 52.8%. Reconstruction of the symphysis was a high-risk exposure variable (OR 30; p = 0.0003). Only one patient underwent a successful dental rehabilitation.

CONCLUSION

The use of a porous titanium 3D- implant for mandibular reconstruction in head and neck cancer patients resulted in high rates of implant exposure and of implant removal, notably when symphysis involvement.

Comparison of surgical outcomes between primary plate and fibular flap transfer for reconstruction of segmental mandibular defects

PURPOSE

Although two ways of reconstruction have been reviewed for a long period, comparison of large sample size with nearly randomized patient selection is rare. Here, we compare the surgical outcomes of these two methods from two large medical institutes.

METHODS

Totally 176 patients were included from two medical centers with different protocols, 62 patients from MacKay Hospital repair defects with fibula flaps using reconstruction plates. Also 114 patients from Kaohsiung ChangGung Hospital treat with reconstruction plates combine anterior lateral thigh flaps, in which 12 cases had secondary fibula flap after plate exposure. Electronic medical records were reviewed retrospectively. Short (3-12 months) and long-term (>12 months) outcomes were evaluated.

RESULTS

Short-term evaluation revealed that the secondary fibula had a higher rate of vascular complications (33 vs. 6%, p = .02). Primary fibula had a higher risk of post reconstructive surgical debridement (60 vs. 40%, p = .018). Long-term follow-up revealed radiation therapy significantly worsened bone healing (p = .03). Primary fibula had a lower rate of screw loosening (14.0 vs. 40.3%, p = .002). Radiation therapy did not increase the plate exposure rate among the groups (33 vs. 27%, p = .389). Disease free survival showed no significant difference between two groups (53.1 ± 3.5 vs. 47.8 ± 2.8 months, p = .317).

CONCLUSION

Primary fibula reconstruction should be considered whenever possible to reduce the risk of late complications and simplifies the management after a potential plate exposure. Notably, radiation therapy apparently has no significant effect on plate exposure rate both in ALT or fibula groups.

Biomechanical In Vitro Study on the Stability of Patient-Specific CAD/CAM Mandibular Reconstruction Plates: A Comparison Between Selective Laser Melted, Milled, and Hand-Bent Plates

Study Design

An experimental in vitro study.

Objective

Plate fractures are a recurrent problem in alloplastic mandibular reconstruction. Hypothetically it can be assumed that computer-aided design (CAD)/computer-aided manufacturing (CAM) reconstruction plates have a higher stability than conventional hand-bent plates. The aim of the study was to compare additive and subtractive fabricated CAD/CAM mandibular reconstruction plates as well as conventional plates with regard to their biomechanical properties.

Methods

In a chewing simulator, plates of 2 conventional locking plate systems and 2 CAD/CAM-fabricated plate systems were compared. The plates were loaded in a fatigue test. The maximum number of cycles until plate fracture and the plate stiffness were compared.

Results

While all conventional plates fractured at a maximum load between 150 and 210 N (Newton) after a number of cycles between 40 000 and 643 000, none of the CAD/CAM plates broke despite a nearly doubled load of 330 N and 2 million cycles. Both CAD/CAM systems proved to be significantly superior to the hand-bent plates. There was no difference between the 2 CAD/CAM systems.

Conclusions

Concerning the risk of plate fracture, patient-specific CAD/CAM reconstruction plates appear to have a significant advantage over conventional hand-bent plates in alloplastic mandibular reconstruction.