John Allen was born on November 4, 1810 on his father's farm in Broome County, New York, United States. He was the son of Nirum Allen, physician and farmer, of the family that had produced General Ethan Allen in the preceding century. While he was still a small boy, his family removed to Ohio.
Allen began the study of dentistry at the age of nineteen with Doctor James Harris of Chillicothe, Ohio. He also studied medicine at the medical college of Cincinnati, receiving the degree of Doctor of Medicine.
About 1830 Allen removed to Cincinnati and began to practise. In 1853 or 1854 he removed to New York City, where he continued to practise dentistry until his death from general debility in 1892, at his home in Plainfield, New Jersey.
The highest type of artificial denture then known was formed of porcelain teeth, singly or in blocks, ground and fitted together and riveted or soldered to gold plates swaged to fit the mouth. There was no way to prevent the seeping of the oral secretions into the interstices between the teeth, and there was no adequate means of restoring the contour of the face where it had shrunken or fallen in because of absorption of the tissues. Allen first devised what he called "plumpers, " forms adapted to fill out shrunken parts, to be attached to the denture. Later he took out a patent (December 16, 1845).
Then began the major task, the devising of the denture itself. First he acquired a thorough knowledge of the making of porcelain teeth. He soon found that gold, the commonly accepted base for artificial dentures, melted at a temperature so low that no porcelain that would resist the oral fluids could be fused upon it. Platinum, only, afforded the necessary characteristics. Several years devoted to the working out of formulas for porcelain bodies and methods of procedure developed "continuous gum". The "gum" is represented by porcelain suitably colored, embracing the porcelain teeth, attaching them to the platinum plate, and continued to cover its lingual surface without seam or crevice. It allows any desired arrangement of the teeth, and is immune to the action of the oral fluids. A patent was granted December 23, 1851, and almost immediately there began the first patent litigation in which dentists were interested.
Allen sued Doctor William M. Hunter, who had been working along the same lines, for infringement. After several years of acrimonious controversy, legal and literary, the case was decided in favor of Hunter.
He filled a professorship at Ohio College of Dental Surgery for several years.
He became a member of the American Society of Dental Surgeons at its second annual session (1841).
Allen was twice married: in 1835 to Charlotte Dana, by whom he had one son; and in 1846, to Mrs. Cornelia Reeder, by whom he had one daughter.
