Drs. Marden Alder, David Ord, and Steven Smith are infusing the UNLV School of Dental Medicine’s curriculum with instruction in forensic dentistry techniques.

Dental Detectives

UNLV’s top forensic experts are training the next generation of dentists to use their skills to battle both crime and terrorism.

By Barbara Cloud

A trench-coated bloodhound named McGruff urges citizens to “Take a Bite out of Crime,” but few realize how much biting is a part of crime.

Using bite marks to track criminals is the challenge for forensic dentists associated with the UNLV School of Dental Medicine: Dr. Steven Smith, associate dean for clinical services; Dr. Marden Alder, an expert in dental diagnostics; and Dr. David Ord, director of dental informatics.

They believe that, whether it is identifying victims of a hotel fire, working domestic violence cases, or tracking teeth marks left at the scene of a murder, dentists with training in forensics have become a valuable asset to law enforcement and have a growing role in the war against terrorism. At UNLV, the group is infusing the dental school curriculum with comprehensive instruction in forensic techniques.

Smith developed an interest in forensic dentistry in the late 1970s, when little training on the subject was available. “In 1978 I was a member of the oral diagnosis/oral medicine faculty at Northwestern. Patient folders containing treatment records, dental X-rays, and dental chartings would frequently be requested by the medical examiner or police agencies for forensic purposes. I started to wonder about who was receiving the records and where they received training in dental forensics.”

A survey at the time indicated that dental school curriculums barely covered the subject. “It turned out to be about an hour lecture in their programs,” Smith says.

Unfortunately, not much has changed, he says. “Only minimal emphasis is placed on forensic dentistry today. That’s got to change.”

Alder’s introduction to forensic dentistry was more personal and highlighted for him the tremendous service dentists can provide their local communities. “I was practicing in a rural Arizona town when five of my patients were incinerated in a car crash,” Alder says. “The coroner in Tucson asked for records and help in the identification – there were eight people in the van; two were personal friends. I then realized that identifying bodies was a real service to families – it’s something the family really wants to get over with.”

Like most means of identification, including fingerprints and DNA, dental forensics is based on statistics. While it is possible for two people to have identical dentition, the odds against it are so high that the legal system relies on dental identification to both confirm and rule out a person’s identity.

“People often go to a dentist more than they go to a physician, and the types of treatment dentists provide offer unique identification opportunities,” Smith says. “So, we are in a prime situation to assist in identification.”

In addition to the more routine dental procedures, students such as Casey Allman are learning how to use their skills to assist law enforcement agencies and identify victims of mass tragedies. The dental school emphasizes the need for students to use computer technology to enhance their future practices and improve the sharing of vital forensics information.

He noted that forensic dentists saw a wide range of dental techniques when working to indentify victims of the World Trade Center attack. Identification was helped by the fact that dental records were readily available. “Those making dental identifications of victims of the attack saw every type of tooth implant system available.”

Smith sees a growing role for dentists in national security. To ensure correct identification, bodies from Operation Iraqi Freedom were processed forensically – including the use of dental records – not just by reading dog tags, Smith says. He also predicts dentistry will play an increasing role in responding to bioterrorism and other catastrophic events.

A recent American Dental Association conference addressed the concern that not enough medical doctors are available to handle a major terrorism attack. “We have 165,000 dentists who could assist,” Smith says. “Dentists can give injections, suture tissue, and administer medications. We need to make sure that our dental school graduates are properly trained for this kind of work.”

But most often, UNLV’s dental graduates are likely to be called upon to help police investigators in violent crime cases. Each dental educator has chilling stories to tell about the cases he has worked. They use the stories, together with pictures both graphic and gruesome, during instruction of future dentists.

“I am surprised that people are so interested in forensics,” Smith says, shaking his head. “They ask me, ‘How can you see this terrible stuff?’ Yet these same people are glued to CSI: Las Vegas. They also thrive on Patricia Cornwall’s mystery novels – she does a pretty good job of authentically portraying forensic investigations.”

Dentists, skilled in making casts of mouths in order to replace teeth, can use their experience to cast evidence otherwise prone to disintegrate.

Take pizza, for example.

In one particularly ugly Chicago murder case, two carpenters building a deck on an executive’s home carefully observed her comings and goings. After completing the job, they returned one day with a truck and were in the process of loading it with her belongings when she came home unexpectedly. After duct-taping her to the floor and killing her, they went on with their loading.
As they hoisted a freezer into their truck, a door came open and a couple of frozen pizzas fell out. They decided to take a lunch break, cooked the pizza, and ate it at a table they had placed over the woman’s body, leaving partly chewed pizza crusts scattered around the body.

Enter the forensic dentist.

Smith researched pizza-eating habits and made plaster models of the crusts to use as evidence in court after the original pieces disintegrated. He was able to show that the bite patterns on the crusts matched the murderers’ teeth.
More often, however, it is bites on people that lead investigators to the perpetrators in a criminal case. “In a rape, there is almost always some biting,” Smith says, either by the victim or by the rapist.

He recalled a rape and murder in an affluent Seattle suburb. The murderer followed a recently widowed woman home. She was later found with multiple stab wounds from multiple weapons. “The murderer also put a Clue game next to the victim’s head, teasing the investigators to figure out where she was killed because blood stained the white carpet throughout the house,” Smith says. “Police had the weapons – a screwdriver, a knife, a corkscrew, and a hammer – but nothing really to tie this to a suspect. When all was said and done, the only identifying mark was a human bite.”
Still, sometimes a bite is not a bite.

In one of Smith’s cases a victim had been stomped to death and appeared to have a lot of small bite marks on his body. “It turned out that the heel on the murderer’s shoe had broken off and the nails were exposed. That’s what made the marks that looked like bites,” he says.

Hardware also figured into a malpractice investigation that Smith was asked to assist using his forensic skills. A dentist had done a root canal but had run out of the small posts normally used to form the foundation for a crown. “So he went to his tool box and came back with a wood screw and built a crown preparation around the screw,” Smith says. “Unfortunately, the crown loosened, and saliva got in and rusted the screw. The person died of a brain abscess.”

Alder remembers a case in which a dentist used a magic marker to draw “cavities” on the X-rays of a 6-year-old. Fortunately the child’s mother had already taken the boy to another dentist who had pronounced his mouth free of cavities based on another set of X-rays. Suspicious of the sudden deterioration of the boy’s teeth, the mother complained to authorities, and the fraud was discovered. Alder ties this example into his instruction.

“We want our students to be good dental diagnosticians,” he says, “able to recognize abnormalities such as the difference between real and fake cavities on an X-ray.” He added that this also helps students recognize when the patient should consult a specialist.
As part of that training, future dentists must make use of computer technology. Already dentists and law enforcement officers are exchanging dental records electronically.

Dr. David Ord, director of dental informatics and applied technology, says the potential for sharing information has barely been tapped. The school’s emphasis on using technology in the field will result in students who are better prepared to practice, he says.
“On a national level, we’re working to improve our ability to transmit electronically so forensic teams have immediate access to the records when they are working crash sites or death investigations,” he says. “In the future, there will be software to maintain a database of dental records on missing people. UNLV is fortunate in that there are more experts in forensic odontology here than any other place in the nation.”

Dr. Edward Herschaft, a dentist noted for his forensic work, joined the UNLV faculty this fall. In addition, Dr. Ray Rawson, ’64 BS Zoology and ’78 BS Anthropology, is a local dental forensic expert who has worked on a number of high-profile criminal cases as well as the 1980 MGM Grand fire. The state senator also teaches at UNLV and at the Community College of Southern Nevada.

In such an atmosphere, the dental school is well positioned to provide cutting-edge forensic dentistry education. The school is new and not set in traditional ways. Its emphasis on an integrated curriculum is attracting both top-notch students and faculty, Alder says. “Most dental schools are compartmentalized; UNLV is vertically and horizontally integrated. We will turn out well-rounded practitioners able to hit the ground running.”

But, to speak of forensic dentistry as a specialty of its own, like orthodontics, is misleading, says Alder.

“One of the misconceptions among students and dentists alike is that you can ‘go into’ forensic dentistry,” says Alder. “There are only a handful of people across the nation who can make a living in forensic dentistry. It has to be an adjunct to a regular dental practice, so it is important that dentists learn what to do and then pool their skills as a team to do the identification or whatever is required.”