The Biomechanical Properties of Human Craniofacial Sutures and Relevant Variables in Sutural Distraction Osteogenesis: A Critical Review.

Sutures are synarthroses connecting the bones of the head with each other through a fibrous sutural ligament. The knowledge of their biomechanical properties is relevant in the application of regenerative techniques for the treatment of craniofacial conditions, such as the sutural distraction osteogenesis (SDO). However, their mechanical characterization has not received a systematic approach, and both clinical treatments and virtual simulations lack clear mechanical parameters. Online databases (PubMed, Cochrane Library, Google Scholar), references of full-text articles, and previous reviews of the literature were searched. Articles quantifying the biomechanical properties of human sutures were included without date, language, or publication restrictions. A qualitative analysis was carried out based on source, sample, load, and measurement characteristics. Subsequently, mechanical parameters were discussed for each suture analyzed. No previous review was found debating the topic. Seven studies were included, only six sutures were analyzed among the about 39 existing ones, and important situations such as compressive and static loading were not considered. Only three studies analyzing the coronal, sagittal, and metopic sutures provided a clear description of the methods and determined parameters of sutures of infants and children. Although a selective load application on sutures is capable of modifying the craniofacial development, little is known about the optimal forces to be applied. The present findings may help to estimate the forces transferred to the sutural ligament during SDO when the strain is measured, and to advance the rationale of the application of certain parameters to optimize the clinical outcome.