De difficili infantum dentitione - 1776
Johann Christoph Pohl (1706-1780) and Quaas Benjamin Ferdinand
De difficili infantum dentitione, (Difficult dentition in children is a 15-page dissertation thesis defended by Quaas Benjamin Ferdinand, the doctoral student with the thesis supervisor, Professor Christopher Johann Pohl at the University of Leipzig in Germany in 1776. The student’s name appears only on page XI of the thesis. As it was customary, the supervising professor had his name on the cover.
There is very little known about Quaas Benjamin Ferdinand, the doctoral student, except that the same year in 1776 he defended a second thesis at University of Leipzig with Professor Ernst Gottlob Bose under the title of De vesicatoriis recte utendis (The proper use of blistering agents).
More is known about Johann Christopher Pohl a distinguished professor at the University of Leipzig. Pohl was born in Lobendau, Germany in 1706 and died in Leipzig, Germany in 1780. His studied philosophy at the University of Leipzig for 10 years (1717-1727). Subsequently studied medicine, and by 1747, became professor of anatomy, physiology, surgery and pathology. Pohl was a member of the famous Deutsche Akademie der Naturforscher Leopoldina, (the Leopoldina German National Academy of Sciences), established in 1652. He was on the advisory council on environmental and medial topics. Throughout his long and distinguished career, he mentored doctoral students on a variety of topics. Pohl’s son, Johann Ehrenfried Pohl, also attended the University of Leipzig and received his doctorate in botany and medicine.
Teething was considered a cause of infant death even in antiquity. Because death occurred around the time of teething, an incorrect association was made and never questioned over the centuries. In 1570 the famous surgeon-barber, Ambroise Pare suggested lancing the gum to ease the eruption of deciduous teeth. Quaas was perpetuating the myth that teething caused inflammation and needed treatment.
The dissertation on difficult dentition describes a young child’s reaction to a problematic tooth eruption. This work is not particularly original even for 1776. His thesis looks at the available literature on the topic and quotes some of the classic authors including Galen, Vesalius, Albini and John Hunter, who just 5 years prior published his seminal book on the natural history teeth.
He starts by describing the different “’diseases” or “attacks” children suffer from teething. On page 4, he describes the formation of a softer bone in the infant, describing it as “cheese-like” until it starts to “lose water” and becomes harder. On the formation of the jawbone, he states “on the internal side of the alveolar socket teeth are tightly connected with the periosteum of the alveolar sockets, on the external side lacks periosteum and feels like ivory, like a glass plate, so it could easily cause pain when in the presence of cold or warm stimuli.” He goes on establishing the average age for tooth eruption around 7-8 years and lists the order of tooth eruption: incisors first, canines, along with the posterior or “cheek teeth” next, and finally the wisdom teeth for a total of 32 teeth. He discusses the different layers of the teeth, describing dentin as “hard and rough”, and enamel like “glass or ivory”.
The symptoms of teething are presented as fever, red cheeks, abdominal swelling, and constipation. Quaas treats this with anti-inflammatory agents and a topical emollient, for constipation. After seven days, the child’s symptoms are observed to subside. Quaas then intervenes surgically (presumably by lancing) and discovers that there may be fluid where it is not expected (possibly a follicular cyst in the gingiva) that caused the inflammatory reaction.
Overall, this is neither original, nor groundbreaking, but it is a typical content and length for 18th century dissertation theses at medical schools.
(Based on research and essay by Manal Tareen, class of 2024 as part of her assignment in the Elective in History of Medicine and Dentistry Course Fall 2020). Edited by Andrew I Spielman.