1998 Fiscal Year Final Research Report Summary
Release of mercury from dental amalgam fillings and behavior of the mercury in a living body
| Project/Area Number |
09672024
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
補綴理工系歯学
|
|---|
| Research Institution | Aichi-Gakuin University |
|---|
Principal Investigator |
TAKAHASHI Yoshifumi Aichi Gakuin University, Dental Materials, Associate Professor, 歯学部・歯科理工学講座, 助教授 (00090142)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KAMEYAMA Yoichiro Aichi Gakuin University, Pathology, Professor, 歯学部・病理学講座, 教授 (70113066)
TANAKA Hironori Aichi Gakuin University, Pathology, Assistant Professor, 歯学部・病理学講座, 講師 (50271383)
TSURUTA Shozo Aichi Gakuin University, Dental Materials, Assistant Professor, 歯学部・歯科理工学講座, 講師 (40183488)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Amalgam / Rat / Mercury / Organ / Blood / Photo emulsion method / Mercury granule |
|---|
| Research Abstract |
1. Release of Mercury from Dental Amalgam Fillings in pregnant Rats and Distribution of Mercury in Maternal and Fetal Tissues.
Experimental animals received one amalgam filling. On days 2, 8 and 15 of pregnancy, Hg exhaled by the rat was measured serially for 24 hours. The animals showed large amounts of Hg on day 2. The amount of Hg tended to decline as time elapsed but marked amounts were observed even on day 15. The amount of Hg increased particularly after the animal took food. In mothers, the highest Hg concentration was found in the kidneys followed, in decreasing order, by the lungs, liver, placenta and brain. The highest Hg concentration among fetal organs was found in the liver, followed by the kidneys and brain. Hg concentrations in maternal organs and fetal liver were significantly higher than those of the controls, and concentrations in maternal whole blood, erythrocyte and plasma, and fetal whole blood were also significantly higher. Hg concentrations in the fetal brain, li
… More
ver, kidneys and whole blood were lower than those of the maternal tissues.
2. Release of Mercury from Dental Amalgam Fillings in Pregnant Rats and Mercury Contents in Their Blood and Urine Samples
Twenty rats were equally divided into four groups (Groups A, B, C and D). Groups B, C and D received amalgam fillings in 1, 2 and 4 maxillary molars, respectively. Group A received no treatment. On days 2, 8 and 15 of pregnancy, Hg exhaled by the rat was measured serially for 24 hours. Urine samples were collected at intervals of 2 days. The amount of Hg tended to decline as time elapsed but marked amounts were observed even on day 15. Blood samples were drawn directly from the heart. The amalgam area was calculated using a personal computer. Hg concentrations in maternal whole blood, plasma and urine correlated to the amalgam area and Hg vapor exhaled by the rats.
3. Histological Observation of Mercury in rat tissues with amalgam fillings.
Twenty female rats were used as experimental animals and ten rats were employed as controls. Experimental animals received 4 amalgamfillings. In sections from the brain and liver of the experimental animals, Hg deposits were not found, while the largest deposits of Hg were found in the kidneys. Dense accumulations of Hg were located primarily in the proximal tubule cells. Less
|
