Investigation Of Caries Susceptibility In Rats With Iron Deficiency Anemia Based On Salivary Biochemical Indices

Objective:To analyze the effect of the change of salivary biochemical indexes on caries susceptibility after iron deficiency anemia in rats by establishing an iron deficiency anemia model in SD rats and detecting the difference of oral salivary biochemical indexes,and to observe the effect of anemia on teeth,salivary glands and splenic cell tissues.It is expected to obtain the mechanism of the effect of iron deficiency anemia on caries,and provide guidance for the treatment and prevention of childhood caries in the clinic.Methods:1,20 1-month-old SD female rats were randomly divided into 2 groups and fed custom-made chow with different iron content of low iron(12 ppm)and normal iron(45ppm)to construct the low iron group(IDA)and normal group(NG)rat models.The rats in the low iron group were fed with 1-2 ml of blood discharged from the inner canthus of the eye under isoflurane gas inhalation anesthesia every week during the feeding period,and the levels of routine blood(HGB)and serum ferritin(SF)were measured after 2months to determine whether the modeling was successful.2,After successful modeling,rats were injected intraperitoneally with trichothecene(5 mg/kg)under isoflurane gas inhalation anesthesia to promote salivary secretion,and1.5 ml of uncontaminated saliva was pipetted into sterile EP tubes,centrifuged at 3000 rpm,and the supernatant was extracted for enzyme-linked immunosorbent assay(ELISA)measurement of salivary secretory immunoglobulin A(s Ig A),lactoferrin(LF),lysozyme(LYS),and lactate dehydrogenase(LDH).Trace elements(calcium,iron,zinc)and PH values in saliva were measured by atomic absorption method.3,Rats were executed under anesthesia,and the lower jaw incisors were taken,and the Vickers microhardness and elemental composition of the teeth were determined by microhardness,scanning electron microscopy and energy spectrometry.4,Take the teeth,salivary glands and spleen tissues of rats,make pathological sections,HE staining,observe their cell and tissue morphology and structure.Tooth and spleen tissue sections were Prussian blue stained to observe iron deposition.Results:1,Blood indexs: The HGB and SF test results of rats in the low iron group were lower than those of the normal group,and the differences were statistically significant(P< 0.01).2,Salivary indexes: sIgA,LF,LYS and LDH levels in the saliva of rats in the low iron group were lower than those in the normal group,and the differences were statistically significant(P < 0.01).PH value showed no statistical difference between the low iron group and the normal group(P > 0.05).The results of calcium,iron,zinc measurement showed that the low iron group was lower than the normal group,and the differences were statistically significant(P < 0.01).3,Dental indexes: Visual observation showed that the incisors of rats in the low iron group had a chalky appearance,while those in the normal group had a rusty appearance.Under the sweeping electron microscope,a large number of pores and uneven crystal deposition on the enamel surface of the lower incisors of rats in the low-iron group were seen,while the enamel surface of rats in the normal group was smooth and flat with uniform and dense structure.The iron content on the tooth surface of the rats in the lowiron group was consistent with the results in saliva,which was lower than that of the normal group,and the difference was statistically significant(P < 0.05).However,the results of zinc on the surface of the teeth of the rats in the low iron group were the opposite of those in saliva,which were higher than those in the normal group,and the difference was statistically significant(P < 0.05).There was no statistical difference between the two groups of rats in terms of calcium,phosphorus,magnesium content on the tooth surface and Ca/P ratio(P > 0.05).The results of Vickers microhardness measurement showed that the tooth hardness of rats in the low iron group was slightly lower than that of the normal group,and the difference was statistically significant(P < 0.05).4,Pathological indexes: The HE staining results of salivary glands,teeth and spleen of rats in both groups were not significantly different.In addition,there was no significant difference in the results of Prussian blue staining of teeth,and no significant iron deposition was seen,but the iron deposition in the spleen of the low iron group was significantly reduced compared with that of the normal group.Conclusion:Iron deficiency anemia in rats led to a decrease in salivary antimicrobial protein and trace element content and a decrease in tooth hardness,which increased caries susceptibility.Iron deficiency had no effect on salivary gland and spleen morphology.No significant iron deposition was seen in the spleen of low-iron rats.