A REVOLUTIONARY NEW ENDODONTIC IRRIGANT
- MTAD
Various concentrations of sodium hypochlorite
(NaOCl) have been used as root canal irrigants for many decades.
The main advantages of NaOCl are its toxicity to most microorganisms
and its ability to dissolve vital and necrotic tissue.
The use of NaOCl, combined with rubber dam isolation
remain as the cornerstones of successful endodontic treatment.
The main disadvantages of NaOCl are its unpleasant
taste and odor, and inability to remove the smear layer. Removal
of the smear layer with chelating agents such as EDTA is important
for allowing NaOCl to penetrate infected dentinal tubules. Contemporary
nickel-titanium rotary instrument techniques create a smear layer
that can prevent penetration of disinfecting solutions into dentinal
tubules.
A new endodontic irrigant, currently
undergoing FDA approval, will provide smear layer removal and
disinfectant properties in one solution.
MTAD
(not to be confused with MTA - mineral trioxide aggregate - the
Portland Cement material used to repair root perforations) is
a liquid that is composed of the following ingredients:
MTAD Mixture
Tetracycline citric Acid and Detergent. The detergent (Tween
- 80) is a surfactant that reduces surface tension and allows
the liquid to flow into dentinal tubules. Citric acid is available
for smear layer removal. Tetracycline acts as the disinfectant.
The tetracycline (actually doxycycline) is also known for "substantivity",
meaning that it binds to calcified tissue and can be released
gradually over a period of time. Additionally, doxycycline has
a low pH and exhibits anti-collagenase activity, further enhancing
anti-bacterial properties. MTAD maintains its efficacy against
Enterococcus faecalis when diluted as much as 200 times.
To date, several carefully controlled
MTAD in vitro studies have been conducted at Loma Linda University
School of Dentistry.
Current research suggests maintaining sodium
hypochlorite as the irrigant of choice for dissolving vital and
necrotic tissue, then enhancing root canal system cleansing by
using MTAD as a final "soak". Another important finding
of the current research is the ability of MTAD to exert its antimicrobial
efficacy during brief exposure times (The time of root canal instrumentation).
This property may eventually obviate the need for intracanal medications
such as calcium hydroxide placement that requires multiple patient
visits.
Many materials and devices are introduced
through the years that claim to be revolutionary, but we believe
that MTAD will have a significant impact on endodontic treatment
regimens.
Shabahang
S, Pouresmail M, Torabinejad M. In vitro antimicrobial efficacy
of MTAD and sodium hypochlorite. J Endodon 2003;29:450-452.
ESCONDIDO
ENDODONTICS 488 EAST VALLEY PARKWAY SUITE 307 ESCONDIDO, CA 92025
(760) 739-1400
FAX (760) 739-1100 www.escoendo.com
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