History of Endodontics aae/abe



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Can CaOH2 diffuse through dentin?





  1. 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.




  1. Foster – CaOH2 diffuses through root dentin to exterior surface, removal of smear layer may facilitate this diffusion.




  1. Nerwich/Figdor/Messerhydroxyl 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.




  1. Orstavik; Wang/HumeBuffering capacity of dentin inhibits OH- ion diffusion


Does CaOH2 weaken Dentin?

YES


  1. Andreasen 2002In 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.




  1. 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




  1. Messer 1984 – Antimicrobial action of CMCP sealed into pulp camber is of short duration (1-2 days)




  1. Harrison 1979 – CMCP and formocresol did not increase or decrease the incidence of interappointment pain.




  1. 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)




  1. 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

  1. 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




  1. 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.




  1. Ferguson 2002 – CaOH2 + CMCP when in direct contact were effective antifungal agents (against C Albicans)

Do intracanal medicaments decrease pain?

NO


  1. Hasselgren 1989 – The use of various dressings did not contribute to the relief of pain.




  1. Trope 1990 – No significant difference was found in the flare-up rate among the three intracanal medicaments (Ledermix, CaOH2, and CMCP)




  1. Walton 1977Post-treatment pain is neither prevented nor relieved by medicaments such as formocresol, phenolics (CMCP, Cresatin, eugenol, beechwood, creosote) iodine-potassium iodide, or calcium hydroxide.




  1. Torabinejad – Flare up study – no effect on flare ups with intracanal medicaments









Instrumentation





Classic Instrumentation


  1. Ingle 1955/61Standardization of instrumentation & obturation; Cites UW study for RCT failure: #1- incomplete obturation; ISO is created





  1. Seltzer/Bender 1968 – Histo studies of periapical tissue rxns to instrumentation short and beyond AF; Long = Bad (Inflamm/necrosis)



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