NORWAY — If longtime residents in Norway have “good” teeth, they can probably thank voters who, in 1951, agreed to become the state’s guinea pigs for fluoridation.

“You can see it with patients who grew up with fluoridated water,” said Dr. Maurice Convoy, a Norway dentist and veteran advocate for the use of fluoride in public drinking water supplies.

Others, however, worry that ingesting fluoride could adversely affect other aspects of health.

Convoy says his side of the debate has teeth. He sees the oral heath difference in patients who live in Norway, which continues to add fluoride to its public water system, and those patients who live in Paris, which does not have fluoridated public water.

Sixty-five water systems in Maine — about  76 percent — currently provide fluoridated drinking water to 133 communities, to more than 520,000 people, according to the Maine Center for Disease Control and Prevention.

The American Dental Association says that fluoridation of community water supplies is the single most effective public health measure to prevent dental decay. The Centers for Disease Control and Prevention has proclaimed community water fluoridation (along with vaccinations and infectious disease control) one of 10 great public health achievements of the 20th century.

“The Maine Dental Association is 100 percent behind keeping Maine’s public water supplies fluoridated,” Dr. John Bastey, director of Governmental Relations for the Maine Dental Association, said.

Some cities and towns have resisted fluoridation for decades.

While Lewiston and Auburn began to add fluoride to their system in the 1960s, Augusta and Bangor waited until 1997.

It took Bangor voters three decades and five referendum questions to approve fluoride in the public drinking supply in 1997.

That same year, Mt. Desert voted fluoride out of its public water supply.

“We have worked with 12 towns and cities over the last 10 years or so to keep their public water supplies fluoridated, some as large as Bangor and others as small as Baileyville,” Bastey said.

While fluoride occurs naturally in water, communities adjust the water fluoridation to optimize oral health. It is kept within a certain concentration to avoid excessive and potentially toxic quantities.

Recently, the federal government standardized the concentration across the U.S. to 0.7 parts per million after finding that level was “therapeutic,” across the country, Bastey said.

Previously, the federal government recommended concentrations of 1.2 ppm in cold weather states and 0.7 ppm in warmer climates.

Maine made the adjustment several years ago.

And yet, the practice of injecting fluoride into public water supplies is not without controversy.

Just last week, voters in Bethel in a 2-1 margin decided to keep fluoridation in its public drinking supply, which it has had for 25 years. The issue came to a vote on the annual town election ballot after a nonresident spearheaded the effort citing health concerns about fluoride.

The concerns are varied, Bastey said. Some question the cost, which can run several thousand dollars a year, but are counteracted by the savings in dental care, he said. Some question the health risks, which Bastey said is only relevant if the water is over-fluoridated.

“It’s just not common and it won’t happen in municipal water supplies where they test for fluoride constantly. They’re pretty good at it,” he said.

Bastey said that although 76 percent of Maine’s municipal water supplies are fluoridated — one of the highest rates in the country — only about 50 percent of its residents actually drink the tap water, which cuts down its effectiveness on oral health.

Many in Norway, including Water District trustees, have held on to the belief that fluoridation is good for residents.

Norway a pioneer

The town of Norway was the state’s pioneer in fluoridating its public drinking water supply.

In 1951, local dentist Dr. Arthur Easton, a past president of the Maine and National Dental societies, spearheaded the Maine fluoride movement. He spent six years studying the effects of fluoridation on reducing teeth decay in other parts of the country such as Wisconsin, New York and Grand Rapids, Mich., which was the first city in the country to add fluoride to its public drinking supply in 1945.

Easton, who graduated from Tufts Dental College in 1915 and practised dentistry for more than 60 years in Norway, determined that children drinking a certain level of fluoridated water would have one dental cavity for every three experienced by children who drank nonfluoridated water. The greatest good, he determined by studies of the few states that used fluoride, was found in children who grew up drinking fluoridated water.

Most of the major health organizations, including the American Medical Association, had concluded by 1952 that fluoride in the public drinking supply was safe.

After convincing other local dentists, the Maine Department of Health and Welfare and Maine Dental Association, public officials and residents of fluoride’s merits, town meeting voters agreed in 1951 to start fluoridating the public water supply.

It took more than a year to determine the best way to fluoridate, what equipment and supplies to use and how to engineer the project.

Arsene Blaquiere Sr., superintendent of the Norway Water District, told officials and residents that a dry feeder would automatically control the amount of fluoride that went into the system. It is a foolproof system, he said, and daily tests ensured no extra fluoridation escaped. The cost was about $100 per year.

In 1952, the Norway endeavor was launched in a ceremony attended by Gov. Frederick Payne, and heads of the Maine Dental Association and the Department of Health and Welfare.

Although the fluoridation system has changed over the last 65 years, current Water District General Manager Ryan Lippiincott said Tuesday it cost Norway $600 annually to inject 50 to 75 pounds of granulated sodium fluoride into its public water supply.

That cost was about double several years ago, before Norway reduced the supply from 1.2 ppm to 0.7 ppm to meet the new federal recommendations.

While the controversy is far from over, Convoy and others remain adamant that fluoridation in the water supply — rather than used as a topical fluoride treatment — is by far the right way to improve oral health.

“I had one patient (in his 60s) who only had three fillings in his mouth,” Convoy said of a man who was concerned about fluoride in his water. “I told him his beautiful teeth were the result of fluoride.”

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