Title The long term skeletodental stability of mandibular symphyseal distraction osteogenesis: tooth-borne versus hybrid distraction appliances ABSTRACT Objective: To evaluate and compare the long-term skeletodental stability of mandibular symphyseal distraction osteogenesis (MSDO) achieved with the use of tooth-borne

Objective: To evaluate and compare the long-term skeletodental stability of mandibular symphyseal distraction osteogenesis (MSDO) achieved with the use of tooth-borne versus hybrid distraction appliances. Materials and Methods: Posttreatment and follow-up orthodontic records were collected for 33 patients. The 14 patients who underwent distraction with a tooth-borne appliance had a mean follow-up of 5.08 years. The 19 patients who underwent distraction with a hybrid appliance had a mean follow-up of 6.07 years. Records included intraoral photographs, study models, postero-anterior cephalometric radiographs, and lateral cephalometric radiographs. Changes in a total of 16 measurements were analyzed to compare patients who underwent tooth-borne versus hybrid distraction. Results: Both groups shared several similar and significant (p<0.05) changes from posttreatment to follow-up records. Cast analysis showed a decrease in intercanine width and arch length and an increase in irregularity index. The postero-anterior cephalometric radiograph showed an increase in the width of the interincisal apices. The lateral cephalometric radiograph showed a decrease in the MP-L1 angle. The only statistically significant difference between the two appliances was the intercentral incisor contact point. Conclusion: Changes found are consistent with those found in untreated and orthodontically treated individuals over time. The long-term changes in the current patient sample can be determined to be expected and acceptable. MSDO is a viable treatment option with the use of either a hybrid or tooth-borne appliance.