I am not a medical expert, so to me this story sounds almost like the type of article that would be published in Weekly World News. A quick online search turned up zilch on how the boy could have been born with metal in his molar.
Boy Grows a Silver Tooth in His Head!
Talk About Being Born With a Gold Spoon
Told, O., May 15. — Four hundred dentists from three states looked into the mouth of 6-year-old John Schnittker here, prodded with sharp instruments at one of John’s teeth, shook their heads and turned away. They questioned John’s mother for an hour or so, but confess that they can’t solve the mystery of a baby tooth.
John’s first tooth was filled with silver or some similar metal when it burst through the child’s gum. The case was reported by Dr. Lyman L. Zarbaugh, Toledo dentist. The 400 other dentists who were here attending a convention, laughed at the local doctor’s statements until they were shown.
The child is the son of Mr. and Mrs. A.F. Schnittker, a farmer’s family. He was brought before the clinic by Dr. Zarbaugh. The doctors examined the tooth and then questioned the mother. She told the following story:
“About eight months before the birth of the baby, Dr. Zarbaugh filled with silver a tooth for me. When the baby began cutting his teeth, the first one to break through has a shiny patch on it.
“When I caught the gleam of the metal, I thought he had a pin in his mouth. I called my husband and we brought the baby to Dr. Zarbaugh. He scratched the metal patch on the tooth with an instrument.
“Then he told us that the patch was some kind of metal, probably silver. He said that the mysterious manifestation was perhaps brought about by prenatal influence.”
“It is the strangest case ever heard of” is a composite option of the dentists.
Dr. Zarbaugh said: “The body has enough metal in it for such a manifestation and it doesn’t seem impossible for nature’s laboratory to deposit it all in this tooth.”
Dr. Zarbaugh has watched the development of the molar from the time the molar burst through the child’s gum. He says that he intends to await developments until the child loses its baby teeth. Then he intends to score the molar for further examination.
[Source: The Day Book (Chicago, Illinois newspaper). May 15, 1912]