Clinical And Experimental Studies On The Trans-sutural Distraction Osteogenesis

[objective]1. Treat mid-facial skeleton retrusion of cleft lip and palate patients with trans-sutural distraction osteogenesis technique. Set up three-dimensional measuring system with three-dimensional CT (3DCT) imaging model. Analyze and measure the three-dimensional value changes before and right after the treatment.2. Design and investigate the feasibility of an internal automatic continuous trans-sutural distraction device.[Methods]1. Clinical research29patients were treated with trans-sutural distraction osteogenesis technique. The oldest child was15.8years old. The operation procedures were modified and larger distraction forces were used.20patients'skulls were scanned by thin-layer CT before and right after the treatment, and the CT images were analyzed and managed with Dicom standard and Mimics software. The three-dimensional measuring system was set. And the three-dimensional measuring values of anatomical landmarks were recorded and analyzed.The color difference of the three-dimensional CT images before and right after the treatment were analyzed with Geomagic Qualify11.0software.2. Animal experimentUse the canines as experimental animals. Place the self-designed automatic continuous trans-sutural distraction device subcutaneously and the titanium landmarks on the maximum. Scheduled photographs X-ray and CT examinations were taken after operation.800g,1500g and2000g magnitude distraction forces were used. The X-ray image measuring method was set and the measuring values of landmarks were recorded and analyzed.[results]1. All the patients'deformities improved dramatically after treatment. The operation turned easier and less invasive. No severe complications were found. The distraction periods were shortened.All the CT images managed well with the Mimics software. The three-dimensional measuring system was stable before and after the treatment. Almost all of the three-dimensional measuring values of the anatomical landmarks increased, especially the values relative to the coronary plane. And comparing the changing values. Islu-cp> MCaL/R-cp> MoL/R-cp> MxL/R-cp> BcL/R-cp> OrL/R-cp. Besides, the measuring values relative to the horizontal and sagittal planes showed changes. The variation values were different among different anatomical landmarks. The Ptm (pterygomaxillary fissure) displaced much more than the sella point.The color difference analysis showed the boundary between the abundance and less displaced skeletons. The boundary was more or less coincidence with the Le Fort weak line.2. The canines tolerated the operations well. The device was stable and the springs distracted well. The face and the occlusion relationship displaced forward dramatically after distraction. The measuring values of landmarks showed that2000g magnitude distraction forces acquired a faster distraction process. CT images showed active bone remolding of the maxilla.[conclusions]1. The trans-sutural distraction osteogenesis technique was applicable to a broader range of older children. Modified operation procedure made the operation easier and less invasive. Using properly enlarged distraction forces can shorten the distraction period.Dividing the distraction process into four stages (the initiate phase; the lag phase; the rapid distraction phase; and the maintenance phase) was more appropriate.The displacements of the anterior and inferior parts of the maximum were larger than the posterior and superior parts after distraction. The width and height of the face were also increased after distraction. The trans-sutural distraction osteogenesis could change the mid-facial skeleton in three-dimensionaly, and could make the face more Harmony.The sutural reconstruction and the bone reconstruction were all involved in the trans-sutural distraction osteogenesis process.2. The design of the self-designed automatic continuous trans-sutural distraction device was proved successful. The distraction rate,2000g>1500g>800g.