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Vol 9 No 1

MU Researchers Develop Andrographis Paniculata Gel for Treating Periodontitis

Periodontitis, an inflammatory reaction of the tissues surrounding a tooth, is one of the major causes of dental loss for a majority of people in the world. It also contributes to other physical and mental problems. Studies have shown that in Thailand about 60 per cent of adult males over age 40 have Porphy romonas gingivalis, the bacteria causing periodontitis, and this percentage increases to 80 over age 60. At present, the incidence of periodontitis is increasing in children as well as adults. Thus, protection from and treatment of the causes of periodontitis is the optimum choice for patients in avoiding teeth loss and preventing related illnesses.

Picture of Andrographis paniculata plant

The Andrographis paniculata plant

A group of Mahidol University researchers recently developed a tool for treatment of this common dental problem, as outlined in the article 'Andrographis Paniculata Gel as an Adjunct in the Treatment of Periodontitis' by Assoc. Prof. Dr. Pleumchit Rojanapanthu, research team leader, and Assoc. Prof. Wandee Gritsanapan of MU's Faculty of Pharmacy, and Assoc. Prof. Mulika Sirirat and Assoc. Prof. Cholticha Amornchat of MU's Faculty of Dentistry.

Essentially, the team developed a biodegradable gel, called Andrographis Paniculata Gel (AP Gel), for subgingival administration which possesses in vitro anti-bacterial activity against >Porphy romonas gingivalis. The development process involved extracting substances from the leaves of the >Andrographis paniculata plant, which was then tested for various properties, including physical and chemical qualities, bacteria-killing ability, toxicity and its ability to substitute as an antiseptic. The team intended for patients to leave the Andrographis paniculata substances in the gum space for a prolonged period in order to release the substances over time, which necessitated the production of a gel.

The AP Gel was created from biocompatible and biodegradable carrier substances. The product was tested for stability, antibacterial activity, toxicity and also in clinical trials in comparison with imported drugs. It was found that when mixed with gum lymph, a natural liquid in the gum space, the gel changed its structure to that of liquid crystal, with subsequent slow disintegration properties and hence more effective gradual release of the bacteria-fighting substances.

Clinical studies of the AP Gel subsequently determined that it could be effectively used as an adjunct in the treatment of adult periodontitis. A comparison of the clinical and microbiological effects of subgingival administration of AP Gel and metronidazole gel, a common antibacterial gel, as adjuncts in the treatment of 60 periodontal pockets of 10 adult periodontitis patients over a 49-day period showed that AP Gel seemed to produce the same adjunctive effects as those obtained from metronidazole gel. The percentage of black-pigmented anaerobes was significantly reduced in the AP Gel group at the 5th and 7th week, but this was not found in the metronidazole group. Furthermore, a comparison study of AP Gel and minocycline gel -- another antibacterial gel -- as an adjunct to scaling and root planing dental procedures in the treatment of Early Onset Periodontitis over a 4-month period showed that AP Gel, when combined with root planing, was more advantageous in terms of microbiological results than minocycline gel.

The development of Andrographis Paniculata Gel has deservedly won many accolades for the research team, including an Outstanding Invention Award 2002 in the field of Chemical Science and Pharmacy from Thailand's National Research Council, a Silver Medal at the Brussels Eureka 2001 50th World Exhibition of Innovation, Research and New Technology, and a Certificate from the Bulgarian American Chamber of Commerce & Industry. They were also presented with a trophy from Prime Minister of Thailand Taksin Shinawatra at the Queen Sirikit National Convention Center on Invention Day in February 2002.