Scientists at the Joint POW/MIA Accounting Command in Hawaii last year identified 69 service members missing from past wars, but they continue to try to unravel a Civil War mystery that’s nearly 150 years old.

Who are the two sailors recovered from the famous sunken ironclad USS Monitor, one with a gold ring found dangling on his bony hand?

Two faces have now risen eerily from the depths, thanks to a reconstruction effort at Louisiana State University, and a DNA determination might not be far behind.

"Since we have no dental records, and we have no fillings in these guys’ mouths, we’re going to have to go back to the DNA, and the DNA is going to tell us who these folks are," said Robert Mann, director of the Forensic Science Academy at JPAC.

The JPAC lab, headquartered at Joint Base Pearl Harbor-Hickam, has had the two sets of remains since 2002, when they were retrieved from the Monitor’s once-rotating 120-ton turret.

The 150th anniversary of the ironclad’s sinking is shedding new light on the unidentified sailors as science edges closer to perhaps solving the mystery.

JPAC has collected mitochondrial DNA from both sets of remains, and the National Oceanic and Atmospheric Administration hired a genealogist in 2011 to trace the family histories of each of the 16 sailors who died aboard the Monitor on Dec. 31, 1862, according to NOAA.

The hope is that 150th-anniversary observances will spur maternal descendants of the lost crewmen to come forward to submit DNA samples for comparison.

Progress is being made: NOAA said descendants of seven of 16 sailors who died have been located, and there were "several" recent inquiries from individuals who might be related to crew member Robert Williams. A great-grandnephew of Samuel Lewis also contacted NOAA.

But there also is a "strong dose of realism in our expectations," said David Alberg, superintendent of the NOAA Monitor National Marine Sanctuary.

"For all of the good work of JPAC, it has still been a decade with no DNA match or ID for either men," Alberg said.

If NOAA doesn’t find living relatives of the two sailors, it plans to bury them at Arlington National Cemetery on the 150th anniversary of their death: Dec. 31, 2012.

JPAC, whose job is to investigate, recover and identify the nation’s missing war dead — mostly from World War II and the Vietnam and Korean wars — makes no exception in this case because of its age.

"This is all part of our mission. Even though they were missing (nearly 150) years ago, we still want to do the recovery and identify these sailors and send them home," Mann said.

NOAA said forensic anthropologists at Louisiana State University’s Forensic Anthropology and Computer Enhancement Services Laboratory, which has the acronym "FACES," volunteered their efforts to create the facial reconstructions.

Coinciding with that has been the release of JPAC biological profile information on the two men — the only remains ever found from the Monitor.

Both were Caucasian. One was 17 to 24 years old, and possibly 5 feet 7 imches tall, while the other was 30 to 40 and about the same height.

Mann, who did the biological profile, can tell a lot more than that from the skulls, which were part of complete skeletons that were recovered.

The older man, who has thicker lips and a wider nose in the facial re-creation, has a pipe stem groove in his teeth, Mann pointed out last week on medical-grade duplicates of the skulls.

"You can see the Monitor sailors and Civil War sailors (in photos), a lot of them smoking pipes," Mann said.

The white clay pipe stems were abrasive and over time wore down tooth enamel.

He also broke his nose at some point, had a deviated septum and was "a pretty robust guy," Mann said. "He could have been muscular and had strong bones."

Mann has done further detective work, looking at profile photos of Monitor sailors and comparing them with side views of the two skulls that were recovered.

Identification, though, has proved to be a challenge — even with the list of known lost crew members at a mere 16, based on NOAA’s count. Another 47 sailors escaped when the Monitor sank in a storm on New Year’s Eve in 1862 off Cape Hatteras, N.C.

Some sailors used aliases. In some old cases of ship sinkings, those reported as missing wind up not missing after all.

One of the 16 sailors who perished went by the name John Stocking, but his real name was Wells Wentz, NOAA said.

"The reality is, what we’re having to deal with is the absence of a lot of information. If these sailors had gone missing a year ago, it would have been much easier because we’d have more information," Mann said. "We have no dental records on these individuals, we have no medical records. We’re lucky if we have any photographs."

The Union’s Monitor, which fought to a draw with the Confederate ironclad Virginia (the former Merrimack) on March 9, 1862, ending the era of wooden warships, has slowly been giving up its secrets.

The wreck site was discovered in 1973 and designated the Monitor National Marine Sanctuary by Congress in 1975.

Its revolutionary turret, fortified with eight layers of 1-inch-thick laminated iron and shielding two 11-inch Dahlgren guns, was plucked from 230 feet of water in 2002.

Inside were found the intact skeletons of the two sailors.

The turret was jammed with silt and corrosion, and the bones had to be immersed in flowing freshwater at the JPAC lab for months to desalinate them; otherwise they would have split and warped, Mann said.

More months were spent using little hand chisels to remove rust that was concreted onto bone.

"What we think about is, you’ve got this ship and it’s rocking and listing when it flips over and starts to settle, and whatever’s on the bottom becomes on the top," Mann said.

Despite that, the bones were damaged only slightly from objects moving about.

"We didn’t have to reconstruct the skulls, we didn’t have to reconstruct — that I can recall — any of the bones," Mann said. "None of them were crushed or anything like that. They were in good condition."

The facial reconstructions are estimates that can’t really accurately depict identifiers like lips, ears and eyes, Mann said.

He’s betting on DNA.

Mann said he thought DNA sequencing was complete on one of the sailors.

"We feel pretty confident we’re moving closer to an identification on one and maybe both of them — which is phenomenal from 140-plus years ago," he said.

NOAA’s Alberg said the facial reconstruction is seen as "perhaps our last, best effort to shake some family trees" and get comparative DNA.

"We hope this works, but at some point I believe we need to say we have done all we can and start asking ourselves, as a nation, How and when should we lay these two heroes to rest?" Alberg said.