Histological Lateral Pterygoid Muscle In Condylar Sagittal Fracture Healing Process: The Influence Of Condylar Shape Reconstruction

Temporomandibular joint ankylosis is a kind of serious disease that may causeproblems with masticationn, swallowing, speech, appearance, hygiene, and occlussioneven breathing and mental problems. Trauma is the main cause of TMJA, the proportionof TMJA caused by the trauma according to different studies come to31%~98%.Condylar fracture as traumatic TMJA main reason, in our country’s TMJA come to69%~74%,in the other parts of the world come to80%~98%.General think condylarsagittal fracture, comminuted fracture are the potential model of TMJA. A mass ofresearchs indicate that condylar fractures secondary temporomandibular joint ankylosis ofthe main damage factors include:(1)The serious damage of temporal bone and condylarjoint;(2)The disk’s damage and shift;(3) The damaged articular cartilage surface contactwith each other. Condylar fracture with the above of the three damage conditions, will the three damage conditions to the animal, CT and histological results confirmed theoccurrence of ankylosis, and performance similar to the clinical situation. Due to theankylosis of the TMJ happened theory is still not clear, make it more difficult to treat. Inthis article we combined with our own research is proposed on the basis of the musculuspterygoideus lateralis lead to osteogenesis in condylar sagittal fracture to develop TMJAof the important reasons. This research we use sheep for animal experiment, cause thecondylar sagittal fracture and then divided the animal into two groups at random, onegroup cut off the musculus pterygoideus lateralis, the another group reserved the musculuspterygoideus lateralis. Through the morphology (general macroscopic view) and histology(HE and ponceau trichrome stain) change compared between the two groups in the processof healing the condylar shape and histological changing. And through the Picric acid Siriusscarlet dye, Observe the all types of collagen fiber in the process of wo und healing. Todetermine whether the musculus pterygoideus lateralis in condylar sagittal exists DO infracture healing. for further study of the traumatic temporomandibular joint ankylosismechanism, so as to lay a foundation for prevention of the traumatic temporomandibularjoint ankylosis.Experime nt one was histological lateral pterygoid muscle in condylar sagittalfracture healing process: the influence of condylar shape reconstruction. Choose24adult sheeps only1year old age, divided into two groups at random. The osteotomy causeanimal condylar sagittal fracture, and cut off the joints and attached to the inside. Group Areserved the musculus pterygoideus lateralis in condylar, retain its function. Group B cutoff the musculus pterygoideus lateralis in condylar, blocking its function. After2weeks,4weeks,12weeks and24weeks, all animals were put to death, and separate completelyTMJ observed the general changing, make the HE and ponceau trichrome stain, andhistologic score. The results showed that group A’s condylar have more new boneformation compared to the group B, the condylar shape changing is more seriously. So wecan determine the musculus pterygoideus lateralis in condylar sagittal fracture healingprocess to condylar shape reconstruction influence play a very important role, the morenew bone formation, even happen joint ankylosis. Experime nt two was picrate Sirius scarlet dyeing observation of condylarsagittal collagen fibe rs change in the process of fracture healing. Test the experimentone’s samples, slicing, and picric acid Sirius scarlet dye, observed it under the polarizedlight microscopy. The results found that in the control group, the bone tissue in it wasmain of the red and yellow type collagen fibers, the trabecular bone with a little green typecollagen fibers in the middle. In the experimental group,2weeks, Ⅰ.Ⅲ types of collagenexist at the same time in the cambium.4weeks, still can see Ⅰ.Ⅲ types of collagen existat the same time, in the organization and between trabecular bone there was Ⅲ type ofcollagen increased. At12weeks, Ⅰtype of collagen was the main type, yet the amount ofⅢ type of collagen was reduced, visibly only a small amount of Ⅲ type of collagen wasto be seen. At24weeks, the basic visible collagen was only the Ⅰ type of collagen, the Ⅲtype of collagen has been nearly invisible. As the experimental group the Ⅱ type ofcollagen was not seen, prompting the experimental group was given priority to theintramembranous ossification, no obvious cartilaginous ossification. Prompting themusculus pterygoideus lateralis can lead to DO.In conclusion, Through the animal experiments study found that, the sheep’scondylar caused sagittal fracture with surgery, cut off the musculus pterygoideus lateralisgroup, in the process of fracture healing, condylar morphology change relatively a little,histological section found in the three months the trabecular bone has been mature, it hasalready become more and more balance, and keep the musculus pterygoideus lateralis’function group, in the course of fracture healing process, condylar morphology changeobviously, visibly to see condylar rough hypertrophy, histological section visibly to see inthree months there were a large number of new bone formation, only to six months therestill has the ossification. So we can know the musculus pterygoideus latera lis to condylarshape reconstruction have influence in the condylar sagittal fracture healing process. Thereare more new bone formation, even happen joint ankylosis. By Sirius scarlet dye,prompting the experimental group was given priority to the intrame mbranous ossification,no obvious cartilaginous ossification.Because the musculus pterygoideus lateralis lead tothe DO, the more new bone formation, even happen joint ankylosis.