Are Cellular Bone Matrix Allografts a Viable Option for Mandibular Tissue Engineering and Reconstruction?

Abstract

Background: Traditional mandibular reconstruction has relied on the use of vascularized and non-vascularized autografts. The use of allografts and tissue engineering modalities has risen as an alternative.

Purpose: The purpose of this study was to determine the success of a cellular bone matrix (CBM) allograft composed of lineage committed bone forming cells for mandibular tissue engineering and reconstruction.

Study design, setting, sample: A retrospective cohort study was implemented using data from subjects treated with a CBM at the University of Louisville from 2019 to 2023. Subjects were excluded if they were not treated with a CBM, data were not complete, or postoperative follow-up time was less than 3 months.

Predictor variables: The predictor variables were composed of heterogenous variables grouped into the following categories: demographics (age, sex), medical history (history of penicillin [PCN] allergy, history of diabetes mellitus [DM] and tobacco use), etiology (benign tumor, ballistic trauma, nonballistic trauma, odontogenic cyst, osteomyelitis/ medication-related osteonecrosis of the jaw), mandibular resection length (cm) and type (marginal, segmental), delayed versus immediate reconstruction, and whether an autograft (proximal tibia) with platelet-rich fibrin was used in combination with the CBM.

Main outcome variable: The primary outcome variable was graft success (yes or no). Success was defined as bony union and defect fill (demonstrated on panoramic radiograph) and mandibular stability (based on postoperative clinical examination at 3 months).

Covariates: Not applicable.

Analyses: Descriptive statistics were calculated for each variable. To measure the associations between the risk factors and graft success, Fisher's exact test for categorical variables and the Wilcoxon rank sum test for numeric data were used. A P value of <.05 was considered significant.

Results: The sample included 38 subjects. The median age of all subjects was 46 (interquartile range 32.6) years. Overall, 28 (73.7%) cases were successful. Subjects with a reported PCN allergy or a history of DM had significantly lower success (2, 7.1% with PCN allergy or DM) compared to those who did not (P = .008, PCN allergy; P = .03, DM).

Conclusions and relevance: This is the largest case series of CBM based mandibular reconstruction relative to the available maxillofacial surgery literature. The clinician should consider confirmation of PCN allergy so PCN-type antibiotics can be used. CBMs may be an alternative to autografts.