PH of endodontic medicaments used in pediatric dentistry: effects of dyadic combinations

The optimum pH of an endodontic medicament is close as possible to that of body fluids, i.e., around 7.2 as higher and lower pH's are likely to cause cellular necrosis of tissues in direct contact with the medicament. This study investigated the pH of various endodontic medicaments commonly used in pediatric dentistry, both singly and in the various combinations available for clinical use. The results showed that the pH ranged from a low of 2.90 +/- 0.02 for iodoform paste (Kri) to a high of 12.45 +/- 0.02 for calcium hydroxide (Calyxl). Eugenol showed a pH of 4.34 +/- 0.05, formocresol 2.79 +/- 0.02, and a commercially-available antibiotic-corticosteroid paste (Ledermix) 8.13 +/- 0.01. Addition of up to 50 percent (v/v) of Ledermix or 25 percent Kri respectively did not affect the pH of Calyxl significantly. Although the addition of up to 75 percent Kri to Ledermix caused a fall in pH, the changes are probably not significant clinically. Furthermore, the addition of 50 percent eugenol to formocresol increased its pH significantly. The optimum pH of an endodontic medicament is as close as possible to that of body fluids, i.e., around 7.2. Higher and lower pH's are likely to cause cellular necrosis of tissues in direct contact with the medicament. However with the exception of calcium hydroxide there has been very little information available on the pH of endodontic medicaments commonly used in pediatric dentistry. Medicaments such as formocresol, eugenol and iodoform pastes have been extensively used for endodontic therapy yet very little attention has been given to their pH values.(ABSTRACT TRUNCATED AT 250 WORDS)