Price spent 25 years of his career performing research on pulpless and endodontically-treated teeth, which supported the theory of focal infection, which held that systemic conditions, including complexion, intestinal disorders, and anemia could be explained by infections in the mouth. This theory held that infected teeth should be treated by dental extraction rather than root canals, to limit the risk of more general illness. His research, based on case reports and animal studies performed on rabbits, claimed to show dramatic improvements after the extraction of teeth with non-vital pulps. Price's research fit into a wider body of testimonials in the dental literature of the 1920s, which contributed to the widespread acceptance of the practice of extracting, rather than endodontically treating, infected teeth. Despite contentions in a 1927 review of Price's work of "faulty bacterial technique" in Price's 1925 publication "Dental Infections and related Degenerative Diseases", Price's publication "Dental Infections, Oral and Systemic" was used as a reference in textbooks and diagnosis guides published in the mid-1930s.