DEDHAM – State officials are seeking information from the public about a woman who disappeared 23 years ago, but they insist they have not narrowed their investigation of bones found near Green Lake down to a specific missing-person case.

Bonnie Ledford was 20 years old when she was reported missing from Dedham in 1980, according to Sgt. Steve Pickering of the Maine State Police.

Investigators, however, have found no direct evidence between Ledford’s disappearance and part of a human skull that was found in Dedham by a hunter in 2001, Pickering said Saturday.

Ledford’s case is one of three or four that police are looking into with possible connections to the remains, Pickering said.

“It’s the closest one to this area,” he said of Ledford’s case. Pickering did not say what other missing persons are being considered, but said they are from the Bangor area.

Pickering was among several state police officers who returned Saturday to the woods near Jenkins Beach looking for clues. Assisting state police were University of Maine anthropologist Dr. Marcella Sorg and two of her students.

Investigators, some wearing protective nets over their heads to protect them from biting insects, used hand tools to dig through the soil and a screen sieve to sift through dirt in an area marked off with pink tape. Much of the underbrush in the search area, which covers 200 to 300 square feet, was removed last year by investigators.

Ledford, formerly known as Bonnie Richardson, married in Michigan in 1977 and moved to Maine in 1979, according to state police.

Pickering said police do not have details about the circumstances of her disappearance. He said police have been talking to her former husband, who lives in Maine, to see whether the bones might be hers. Pickering declined to identify the former husband.

“He’s been talked to, to find out if this is her or not,” Pickering said. “He has been cooperative.”

Anyone who might have information about Ledford is asked to contact state police at (800) 432-7381.

According to Sorg, the bones belong to a female believed to be in her 20s and have been in the Dedham woods for at least 10 years. Since the top of the skull was discovered in November 2001, small bones from the woman’s spine and foot also have been found, Sorg said.

According to Pickering, investigators have found no teeth to compare to dental records of missing persons. He said Saturday’s visit to the site was the fourth by state investigators since the skull was found.

Weather, erosion and animals could have moved the remains while they lay in the woods, according to investigators. Pickering said that over the past couple of decades, there also might have been equipment in the woods that could have disturbed the bones.

“This is young growth,” Pickering said of the trees surrounding the dig site. “Skidders and harvesting equipment could have been in here since then.”

Pickering said some paperwork and photos have been found near the bones, but deterioration of the items has prevented investigators from gleaning any useful information from them.

The papers and photos were loose, not in any sort of bag or backpack, Pickering said, and no clothes have been found.

Pickering said it would not be unusual for any clothes that were with the bones to have disintegrated over the years.

“You might find a seam, but otherwise cloth goes fast,” he said.

Sorg said investigators in search of clues are digging a few inches deeper into the soil this year than they did previously.

“Over such a long period of time, things get incorporated into the ground,” the anthropologist said. “It’s a pretty painstaking process.”