Histopathological Study On The Effects Of Dyad Flow On Rat Molar Pulp

PURPOSE:This study aimed to compare the pathological changes of pulp tissue with the new multi-purpose materials Dyad Flow and the mature self-etching adhesive used in the clinical Optibond all in one in rats after deep caries resin filling,and provide a theoretical basis for the rational and reasonable use of new multi-purpose materials.METHODS: 36 male SD rats were divided into A,B two groups randomly,each group of 18.After anesthesia,randomly chose one of the maxillary teeth,then class I cavities with 0.6 mm diameter were prepared on the occlusal surface of the maxillary first molar.The cavities were Close to the pulp.Two kinds of dentin bonding agents(Dyad Flow、optibond all in one)were applied on the surface of the cavities,F00 resin was used for filling after curing.In each group,six rats were sacrificed on day 1,7 and 14 through 4% paraformaldehyde heart perfusion.Remove the experimental teeth,fixed,decalcified,dehydrated,embedded in paraffin,and according to the long axis of tooth.Dissecting the experimental teeth,fixed,decalcified,dehydrated,embedded in paraffin,according to the long axis of the tooth make sagittal sections with the sections thickness for 4um.Then the effect of two materials on pulp tissue was evaluated by HE staining.RESULT:Postoperative day 1,the two groups showed similar histopathological changes,with mild inflammation.There was no significant difference between the two groups in the infiltration of inflammatory cells,histological disorder,reparative dentin formation and bacterial microleakage.Postoperative day 7,the two groups still showed mild inflammatory reaction and reparative dentin formation.There was no significant difference between the two groups in the infiltration of inflammatory cells,histological disorder,reparative dentin formation and bacterial microleakage.Postoperative day 14,the inflammatory cells were not found in all the groups,and all of them had reparative dentin formation.There was no significant difference between the two groups in the infiltration of inflammatory cells,histological disorder,reparative dentin formation and bacterial microleakage.CONCLUSION:Dyad Flow and Optibond All In One have a certain irritation to pulp tissue,and between the two kinds of materials,the biocompatibility of no significant difference.The RDT was inversely proportional to the adverse reaction of the pulp.For the deep hole,especially the RDT is less than 300 um,should not be directly repaired,to do some pulp treatment and then filling.The pulp tissue mainly through the two stages of recovery,one is the production of inflammation,the other is wound repair,and the interactionbetween the two can not be completely separated,with the extension of time,the dental pulp tissue can gradually return to normal..Dyad Flow can be used as the bonding agent for deep caries cavity.