A Biochemical Study Of The Goat TMJ Disc Cells And Self-assembly Construct

Objective: Temporomandibular joint discs are the main tissues that affect oral chewing performance and complex movement,understanding their components of extracellular matrix,and using biochemical methods to determine the similarities and differences of biochemical contents between different stress zones of native articular discs.The spherical basal body of the temporomandibular joint disc was constructed by self-assembled technique,whose biochemical contents were measured and compared with the native articular disc.The differences of formation were discussed,which provided the theoretical basis for the realization of the engineering of temporomandibular joint disc.Methods: The water contents of the native articular discs and the self-assembled basal body were determined by acetone dehydration method.The samples of goat temporomandibular joint discs were divided into the outer,the medial,the anterior,the middle and the posterior zone.The contents of collagen,proteoglycan and GAG were determined by ultraviolet spectrophotometry,comparing the differences between zones.The self-assembled space was provided by agarose wells,making the cells of temporomandibular joint disc polymerized to form spherical basal body.The morphology of the basal body was observed,while the diameter and the biochemical index of the basal body were measured.Resuclts: 1?The water content of the native articular disc was different(77.04% ± 1.24%);The contents of collagen were 0.71±0.43?g/ml in the outer zone,1.09±0.14?g/ml in the medial zone,2.78± 0.52?g/ml in the anterior zone,3.48±0.33?g/ml in the middle zone,and 2.77±0.57?g/m in the posterior zone.There were significant differences between zones(p <0.05)except the anterior and the posterior(p >0.05);The contents of proteoglycan were 0.92±0.01?g/ml in the outer zone,0.94±0.01?g/ml in the medial zone,0.92±0.01?g/ml in the anterior zone,0.95±0.01?g/ml in the middle zone,and 0.91±0.01?g/ml in the posterior zone.The outer zone has no statistical significance when compared with other zones(p >0.05)except with the middle zone(p <0.05),The medial zone has no statistical significance when compared with other zones(p >0.05)except with the posterior zone(p < 0.05),The anterior zone has no statistical significance when compared with middle and posterior zones(p >0.05),The middle zone has no statistical significance when compared with posterior zones(p <0.05).The contents of GAG were 1.29±0.05?g/ml in the outer zone,1.64±0.04?g/ml in the medial zone,1.07±0.05?g/ml in the anterior zone,2.26±0.04?g/ml in the middle zone,and 1.87±0.04?g/ml in the posterior zone.There were significant differences between zones(p< 0.05).2?The diameter of the self-assembled basal body of goat temporomandibular joint cells was 1.163 ± 0.029 mm at 2 weeks,1.65 ± 0.026 mm at 4 weeks,1.71 ± 0.035 at 6 weeks.The contents of water were 90.31±1.1% at 2 weeks,89.19±0.9% at 4 weeks,90.00±0.7% at 6 weeks.There were significant differences when compared with the native articular discs,at 2,4 and 6 weeks(P <0.05).The contents of collagen were 30.064±1.65?g/ml at 2 weeks,31.486±1.61?g/ml at 4 weeks,35.127±3.45?g/ml at 6 weeks.There were significant differences when compared with the native articular discs,at 2,4 and 6 weeks(P <0.05).The contents of proteoglycan 0.142±0.099?g/ml at 2 weeks,0.1468±0.099?g/ml at 4 weeks,0.1517±0.110?g/ml at 6 weeks.There were significant differences when compared with the native articular discs,at 2,4and6 weeks(P <0.05).The contents of GAG were 0.99±0.012?g/ml at 2 weeks,0.7386±0.049?g/ml at 4 weeks,1.4186±0.071?g/ml at 6 weeks.There were significant differences when compared with the native articular discs,at 2,4 and 6 weeks(P<0.05).Conclusion:1 ? The contents of collagen,proteoglycan and GAG of goat temporomandibular joint were different in different zones.2?The diameter,collagen and proteoglycan of the self-assembled basal body of goat temporomandibular joint cells increased in the process of growth,but the contents of GAG did not show an increase.Biochemical contents were different in different zones when compared with self-assembled basal body,suggesting that,close to the native articular discs,engineering of temporomandibular joint discs should be different in different zones;...