The tiny plastic beads found in many popular toothpaste brands are approved by regulators, but dentists are becoming increasingly alarmed that the beads could cause more dental hygiene problems than they solve.

(Crest) (Crest)

Polyethylene plastic beads became all the rage in personal care products -- including toothpastes, face washes and body scrubs -- a few years ago. And the Food and Drug Administration says they're safe.

But the beads do not disintegrate and are not biodegradable, and dentists are concerned that they're getting stuck in the tiny crevices between the teeth and gums.

"They’ll trap bacteria in the gums which leads to gingivitis, and over time that infection moves from the gum into the bone that holds your teeth, and that becomes periodontal disease," dentist Justin Phillip said, according to Phoenix ABC affiliate KNXV. "Periodontal disease is scary.”

The beads are similar to the slightly larger exfoliating beads the Illinois legislature banned this year because the products can't be sifted out of the water supply and can end up in large bodies of water, where they can harm marine life.

But that same substance is in widespread use in toothpaste products, including a variety of Crest products such as Crest 3D White and Crest Pro-Health. And according to Crest, the product is really used only to provide color to toothpaste.

Months ago, Texas-based dental hygienist Trish Walraven sounded the alarm on her personal blog about the harm she has seen done to her patients -- and even her children. She urged her patients to stop using the products.

"Polyethylene plastic is in your toothpaste for decorative purposes only," Walraven wrote. "This is unacceptable not only to me, but to many, many hygienists nationwide. We are informing our patients."

In response, Crest said in a statement this week that it has begun phasing out microbeads from its products, a process that will be completed by March 2016. A spokesman for the company told the Post that he decision was made "months ago" in response to "changing consumer and dental professional preferences."

"While the ingredient in question is completely safe, approved for use in foods by the FDA, and part of an enjoyable brushing experience for millions of consumers with no issues, we understand there is a growing preference for us to remove this ingredient. So we will," the company said in a statement to KNXV. "We currently have products without microbeads for those who would prefer them. We have begun removing microbeads from the rest of our toothpastes, and the majority of our product volume will be microbead-free within six months."

The American Dental Association, which endorses some Crest products, stands behind the beads, citing a lack of clinical evidence questioning their safety.

"The American Dental Association’s (ADA) Council on Scientific Affairs, on an ongoing basis, monitors and evaluates the safety of all ADA Seal-Accepted products," the association said in a statement this week. "If the council’s evaluation determines sufficient scientific evidence exists that an ADA Seal-Accepted product poses a health risk, the council has the authority to withdraw the Seal from that product." At this time, clinically relevant dental health studies do not indicate that the Seal should be removed from toothpastes that contain polyethylene microbeads."

[This post has been updated.]