The Effects of Some Chemicals on Cervix Dentis

¹ Department of Physiology, Tottori University School of Medicine, Yonago, Tottori, Japan

The function of the afferent fibers of the pulp branch of N. alveolaris mandibularis on stimulation by some chemicals was studied in 26 dogs narcotized with N-methyl-cyclohexenyl-methol-barbituric sodium in a search for valuable and fundamental information relative to the etiology of hypersensitive dentin. It was found that the conduction velocity of the afferent nerve resembles that of the A group of cat's nerves.

As stimulating agents, glucose, saccharose, HCl, NaOH, and NaCl were used. Afferent volleys initiated chemically appeared when 50-60 per cent solutions of glucose and saccharose, 10^–3 mol of HCl, 10^–2 mol of NaOH, and 12 per cent solutions of NaCl, respectively, were used. Chemical stimulation on the cervix dentis evoked volleys of discharges for a long time. The conductivity and adaptation mechanism of the system, which consisted of odontoblast and nerve terminal, were discussed.