Tronstad – pH is decreased during resorption. Teeth filled with CaOH2 have increased pH in the surrounding dentin. (7.4-11) The pH of cementum/PDL is not effected by CaOH2 in the canal. Increased dentinal pH may be the mechanism for stopping resorption.
Nerwich/Figdor/Messer – hydroxyl ions derived from a calcium hydroxide dressing diffuse through root dentin. 1-7 days elapse before pH began to rise in the outer root dentin, peaking at pH 9.3 apically after 2-3 weeks.
Andreasen 2002 – In vitro, Immature mandibular incisors (sheep), CaOH2 placed and sealed for ½, 1, 2, 3, 6, 9, or 12 months. Significant in Fracture strength from 2 months – 12 months w/ CaOH2. At 12 months, Dentin Fracture strength 50%of original strength.Limit use of CaOH2 to less than 30 days, Fracture strength was not significantly reduced w/ 30 day CaOH2 period.
Rosenberg 2007 – In vitro, maxillary incisors, CaOH2 placed 7, 28, or 84 days and compared with control (GP/Sealer). Significant in Dentin Fracture strength from 28-84 days w/ CaOH2. Long term use of CaOH2 decreases microtensile dentin fracture strength.
What about CMCP?
CMCP = Camphorated Paramonochlorophenol
Messer 1984 – Antimicrobial action of CMCP sealed into pulp camber is of short duration (1-2 days)
Harrison 1979 – CMCP and formocresol did not increase or decrease the incidence of interappointment pain.
Madison 1992 – CMCP binds to cell membrane lipid and proteins. In addtion to being potent antimicrobial agents, this compound exhibits a high level of cytotoxicity with c.t. (severe inflammation/necrosis)
Barbosa/Siqueira 1997 – Compared CMCP vs. CaOH2 vs. CHX for antibacterial effects clinically and agar diffusion tests (multiple obligate/facultative anaerobes). Clinically (1 wk) – neg cultures: CMCP = CaOH2 = CHX (69-77% red.). Agar: CMCP = CHX > CaOH2
What about CMCP? Continued
Haapassalo/Orstavik 1987 – Studied the disinfection of dentinal tubules – smear layer removal facilitates bacterial invasion of dentinal tubules. Calasept (CaOH2) failed to eliminate E. Faecalis in the tubules. CMCP was more effective. E. Faecalis survived in tubules for 10 days without nutrient supply. Smear layer presence delayed pentration of irrigating solutions
Orstavik/Haapasalo 1990 - Evaluated disinfection of infected bovine dentin sections. E. faecalis, S. sanguis, E. coli, and P. aeruginosa. Only E. faecalis survived 10 d. post withdraw of nutrients. CMCP more efficient than Calasept at eliminating E. faecalis within tubules (60 mins vs. 10 days).This may be only a short term effect as CMCP evaportates rapidly! Smear layer delays the penetration/action of medicaments.
Ferguson 2002 – CaOH2 + CMCP when in direct contact were effective antifungal agents (against C Albicans)
Do intracanal medicaments decrease pain?
Hasselgren 1989 – The use of various dressings did not contribute to the relief of pain.