RESUMO
The study aims to establish trimester-specific reference ranges for serum iodine (SI) in Chinese pregnant women and explore its associations with maternal and infantile thyroid function. Apparently healthy pregnant women were enrolled during their first antenatal visit. Fasting venous and spot urine samples were collected for determining serum and urinary iodine (UI) levels by a validated inductively coupled plasma mass spectrometry. Serum free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), and neonatal TSH levels were tested by electro-chemiluminescent assay. The reference ranges of SI were established by percentile method and reported as 2.5-97.5%. ROC analysis was applied to compare the discriminative ability of SI, UI, and UI to urinary creatine ratio (UI /UCr) in early pregnancy for various thyroid conditions. The trimester-specific reference ranges of SI for Chinese pregnant women were 60.91-114.53 µg/L for the first trimester (T1, n = 1029), 54.57-103.42 µg/L for the second trimester (T2, n = 379), and 52.03-110.40 µg/L for the third trimester (T3, n = 455). Maternal SI at T1 but not UI and UI/UCr was significantly correlated with FT3 (r = 0.393, P < 0.001), FT4 (r = 0.637, P < 0.001), and TSH (r = -0.299, P<0.001). Maternal SI change% from T1 to T2 (but not SI change% from T1 to T3) had marginal correlation with neonatal TSH (r=-0.106, P=0.046). ROC analysis showed that maternal SI at T1 had better predictability for several thyroid conditions than UIC and UI/UCr.
RESUMO
PURPOSE: To compare the stress distribution of dental implants with different body shapes after maxillary sinus augmentation. MRTHODS: Three different implant models varying in implant shape were investigated in D3-type maxilla. All materials were assumed to be linear elastic, homogenous and isotropic. An oblique force of 150 N was applied to the implant. Maximal equivalent von-Mises of supporting bone around implants were measured. All of the models were measured by Ansys Workbench 14.5. Statistical analysis was performed using SPSS 17.0 software package. RESULTS: Highest stress of supporting bone emerged on the crestal cortical site around the implant neck. There was no significant difference in the maximum EQV of supporting cortical bone between different groups; the maximum EQV of supporting trabecular bone in the tapered implant group was much higher than other groups; application of grafts reduced the maximum EQV of both cortical and trabecular bone in all groups. CONCLUSIONS: Tampered implant can induce elevated stress distribution of the upper trabecular bone, which may promote marginal bone loss. Application of grafts after maxillary sinus augmentation could favors in reducing the stress loading of dental implants.
