[Symphyseal bone distraction (part 1): benefit / risk ratio. A systematic literature review]

The purpose of this systematic literature review is to evaluate the benefit / risk ratio of mandibular symphyseal distraction osteogenesis.

Searches were made on Pubmed/Medline and Cochrane for randomized clinical trials and case series involving mandibular symphyseal distraction over the past 20 years with a patient sample greater than or equal to 10.

Of the 92 articles, 25 met the inclusion criteria. A controlled trial was selected, but no randomized trial. The other studies were all case series, 16 retrospective and 8 prospective. Distractors with bone or hybrid anchorage appear to lead to more periodontal and infectious complications due to the buccal position of the jack. Most complications are benign. However, the most difficult event to deal with is distraction device fracture. Symphyseal midline distraction increases the transverse dimension efficiently, reliably and sustainably, and appears to have no demonstrated deleterious effects on the ATMs for the three types of distractors.

Tooth-borne devices are recommended in most cases given their benefit / risk ratio. Furthermore, they do not require a second surgical procedure to remove them.

Mandibular symphyseal distraction osteogenesis is a reliable therapy whose exact limits and reproducibility remain to be defined by future prospective studies.