Do new generation custom subperiosteal jaw implants and zygomatic implants have positive effects on protecting the maxilla during facial trauma?

BACKGROUND: Subperiosteal jaw implants (SI) and zygomatic implants (ZI) are alternatives when dental implants cannot be placed without bone augmentation. This study aimed to compare the impact of SI and ZIs on force distributions during an anteriorly directed trauma towards the maxillary bone, and to examine whether SIs enhance the bony resistance against potential fractures.METHODS: A severely resorbed human maxillary model served as control. Test models received custom SIs and quad-ZIs. Frontal forces of 1700 N, 3400 N, and 5100 N were applied, and the stress values along the fracture lines were analyzed.RESULTS: At 1700 N, no model exceeded the threshold. At 3400 N, the threshold was surpassed at the pterygoid junction in the control model and the Le Fort 3 line of the SI and ZI models. At 5100 N, the threshold was exceeded on all the Le Fort lines in the control model, the Le Fort 3 fracture line, and the pterygoid junction in the ZI model, while only the Le Fort 3 fracture line was affected in the SI model.CONCLUSIONS: SIs and ZIs may protect edentulous atrophic maxillae against anteriorly directed forces with SIs being more effective at higher force magnitudes.