Under the Needle

Brazilian researchers may have a new way to reduce joint inflammation, which they hope could be beneficial to those living with temporomandibular joint disorder.

The researchers have enhanced the efficacy and duration of a drug commonly used to reduce inflammation caused by joint degeneration.

Using lipid nanoparticles containing a high concentration of the drug’s active principle, the researchers have modified the medication to last up to 10 days without the need for followup administration.

The study, conducted by researchers affiliated with the University of Campinas, was published in the journal Scientific Reports. In it, the team used naproxen, an anti-inflammatory drug, in rats with temporomandibular joint (TMJ) inflammation.

‘The TMJs are the joints that connect the lower jaw to the skull and allow it to move up and down, side to side, and back and forth,’ Armstrong said.

The TMJs are often affected by wear and tear, which can contribute to the development of temporomandibular joint disorder (TMD), a condition that affects the muscles surrounding the temporomandibular joints.

‘TMD can make everyday functions such as chewing, talking and yawning painful or difficult,’  said Dr. Richard Armstrong of Legends Dental in Waco, Texas.

The study was supported by the Sao Paulo Research Foundation – FAPESP.

The benefits of using lipid nanoparticles meant that 99.8 percent of the medication was encapsulated.

Tests of the medication on animals found that sustained delivery to the TMJs lowered the activity of leukocytes to the area for up to a week.

Leukocytes are the body’s defense cells that ramp up activity in the presence of illness or injury, such as wear and tear to joints.

Researchers also noticed that prolonged exposure to the drug created lower levels of the proinflammatory cytokines IL-1β and TNF-α. Cytokines are proteins that help regulate the immune system’s response.

Both of these findings indicate that inflammation levels were reduced.

The improved efficacy of the naproxen was also attributed to delivery by injection versus oral consumption, which is ideal, as prolonged use of the medication can contribute to stomach bleeding.

Conventional treatments for TMD often include oral appliances, bite splints and surgery. Other ways to treat the condition include jaw stretches, neuromuscular orthodontics, or guided growth orthodontics, which can help remodel the jaw to correct bite problems.

‘TMD is often a result of a poorly aligned bite or an undersized jaw,’ Armstrong said.

Source: News-Medical.net. New injectable formula to treat joint inflammation has sustained effect for 10 days. 25 October 2019.