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CHAPTER 10
FORENSIC DENTISTRY
INTRODUCTION
Forensic dentistry may be defined as that branchof forensic medicine that applies dental knowledge tocivil and criminal problems. The military simplyexpands this definition to include the unique needs ofthe military services. While it is true that our primarymission is to support requests for aid in forensic dentalidentification, you must understand that dentalidentification is only one of a number of major areasin forensic dentis try. These include: dentalidentification, bite mark analysis, human abuse andneglect, dental malpractice and negligence, and dentalanthropology and archaeology.
As a basic dental assistant, your primary dutieswill be assisting dental officers and civilian dentistswith the dental identification section in forensicdentistry when directed. The other major areas inforensic dentistry will not be covered in this bookbecause they pertain mainly to dental officers anddentists.
PURPOSE
The primary reason we in the Navy have beendirected to establish a forensic dental identification(ID) capability is to assure our ability to assist in the IDof human remains. In most cases this meansidentifying members of the Armed Forces, butoccasionally it may include civilians. We are tasked todo this to meet both the civilian needs and the uniquemilitary needs for positive ID of individuals. The firstfour of these needs are common to both the militaryand civilian communities and include estate,insurance, legal, and psychological considerations.The last two needs are military considerations andinclude manpower and intelligence needs.
ESTATE
Positive ID is necessary to allow probate of the lastwill and testament and transfer of any inheritance tothe deceased's next of kin. Without positive ID, thisprocess could be delayed until the person is declaredlegally dead, or up to 7 years.
INSURANCE
Positive ID also is necessary to allow survivors toproperly claim any life insurance held by the victim.Again, if a positive ID is not accomplished, thepayment of insurance to the beneficiaries could bedelayed for years. This would defeat the purpose forbuying the policy in the first place and could deny anysurvivors the funds needed to adjust to the loss of theprovider's income.
LEGAL
A less common but important consideration is thepossibility of legal action such as malpractice orwrongful death litigation. Obviously, it would be verydifficult, if not impossible, to prove wrongful death ina court of law if one cannot prove that an individual isdead. This would not only eliminate any possibility forcompensation for loss of a loved one, but also couldaffect the legal handling of the deceased's estate as wellas payment of any life insurance benefits.
PSYCHOLOGICAL
The last of the common needs is the psychologicalaspect of an individual's death. The loss of a loved oneis frequently psychologically devastating to those leftbehind. In fact, many persons are not able to accept thedeath of their child, parent, or spouse until long afterthe occasion. Not knowing positively their loved oneis dead complicates this process leading to false hopesand preventing the survivors from getting on with theirlives. A graphic example of this was the tremendousagony experienced by the next of kin of our Vietnammissing in action.
MANPOWER
Simply stated, you need to know who thecausalities are so you can rapidly replace them. If wedo not know who the Sailors are, it will be impossibleto replace them with persons of similar training andskills in their areas of expertise to restore full combatreadiness.
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INTELLIGENCE
You also must know the location and condition ofour personnel familiar with sensitive operationalinformation. If a Sailor who knows the details of anupcoming operation is missing, you need to knowwhether he is wounded, dead, or captured, and if theoperation plans have been compromised.
OTHER METHODS OF IDENTIFICATION
Now that we have established the purpose forforensic dental identification and explained why wehave been tasked to do so, we need to look at whydental techniques have become so important inforensic identification operations. To do this we needto look at some of the other different methods offorensic identification. Various methods of ID havebeen used depending on the individual situation.
Body Characteristics
Many body characteristics can be used to identifyan individual. Recognition includes using visual,scars, deformities, and tattoos methodologies.
Visual recognition—this is the most commonmethod. It is reserved for instances in which no real
doubt exists about the identity of the individual anddeath did not occur under unusual circumstances. Itsdrawbacks occur when changes in appearance becauseof illness, fire, water immersion, or decompositionmake ID quite difficult. Figures 10-1 and 10-2 showsoft tissue trauma from fire and water. Visualrecognition, therefore, is considered an unreliablemeans of identification in medico-legal deathinvestigation and not usually acceptable as positiveproof on the identity of the deceased individual.
Scars—this method is useful in some cases.Surgical scars are probably the most commonly foundbut are of the least value since they are seldomdistinctive. Like visual recognition, scars can change orbe destroyed by the same processes affecting visualrecognition.
Deformit ies —may be either soft tissuealterations or because of bony abnormalities.Radiographs of the deformity on file in the medicalrecord can be useful in the ID process. The bonydeformity must be significantly distinctive, however, tobe of value as a means of ID.
Tattoos —can assist in the identificationprocess. Figure 10-3 shows a tattoo on an arm. Multipletattoos would increase the likelihood of positive
Figure 10-1.Charred remains from fire.
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Figure 10-2.—Remains from immersion in water for two weeks.
identification. Again tattoos are soft tissue evidence assist in establishing the identity of the individual.and therefore are prone to easy destruction by Drivers' licenses, credit cards, ID cards, ID badges, andenvironmental effect. For many reasons, tattoos should passports are just a few such items. In the military, dogbe used only as a secondary means to a positive ID. tags are used specifically for this purpose. Other
Personal Effectsexamples of personnel effects that may be helpful inestablishing an identity include name tags sewn intoclothing, distinctive jewelry, inscribed jewelry, andfamily photographs. Personal effects, however, are the
Personal effects may include anything that isfound on the body of the deceased that can be used to
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Figure 10-3.—Tattoo on an arm.
least reliable means of establishing an identity. Theyare not a physical part of the body, and, therefore, theymay easily be transferred from one individual toanother. In addition, lost or stolen items, and jewelryin particular, are very likely to be found in thepossession of an individual other than its owner.Falsified documents may be found improperlyidentifying an individual as someone else. In mostinstances, the identity established by the personaleffects will prove to be the actual identity of thedeceased, but this must still be verified by a moreobjective, definitive means of ID.
Skeletal Remains
Identification by skeletal remains may be anexcellent means to identify an unknown individual. Insome cases, it can provide positive proof of identitythat is acceptable in a court of law. Identification byskeletal remains requires matching of postmortemradiographs with radiographs that were taken beforedeath. Features that can be used for ID by skeletalremains would include healed fracture sites,pathologic lesions, and medical hardware.
The main problem with ID by skeletal remains isthe fact too few individuals in the general populationhave such characteristics. This makes it difficult torely on as a routine method of ID of an unknown body.
Fingerprints
Of all the methods of ID, fingerprints are probablythe best known. Fingerprints are an excellent meansof positive ID. Figure 10-4 demonstrates a finger-printing technique used by the FBI. Many individualswill argue that fingerprint ID is the most definitivemeans of identifying an unknown set of humanremains, and it is generally accepted that no twoindividuals have the same set of fingerprints.Fingerprint ID, therefore, is always acceptable in acourt of law.
DNA Analysis
DNA analysis, also known as DNA fingerprinting,is a fairly new technology that may replace dentalidentification and fingerprint identification as the mostdefinitive means of identifying unknown remains. Itwill be fully implemented when an adequate databaseof DNA specimens can be established.
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Figure 10-4.—Fingerprinting
DENTAL IDENTIFICATION
Dental ID, like fingerprint ID, is a definitive meansof positive identification of unknown human remains.It also is routinely acceptable as evidence in court. Ithas several significant advantages, and only a fewdisadvantages when compared with fingerprintidentification. The bulk of the remaining chapter willcenter on dental ID.
WHY DENTAL IDENTIFICATION WORKS
Dental evidence tends to survive much better thandoes soft tissue evidence such as facial characteristicsor fingerprints. Teeth are calcified structures and arethe hardest substance in the human body, even harderthan bone. Because they are calcified, they areresistant to the environmental effects that destroy softtissue evidence. Thus teeth are not destroyed byimmersion in water, by desiccation (drying up), or bydecomposition. Even in cases of skeletalization ofremains, teeth are available for ID purposes. Inaddition, teeth are relatively resistant to destruction byfire. However, teeth can be destroyed in rare instancesby heat if the temperatures are greater than 1000°F andthe teeth are unprotected by the soft tissues of thecheeks and lips. Figure 10-5 shows intact dentition of a
charred mandible. Teeth are further protected by thesoft tissue mass of the tongue. The roots of the teeth areencased in the alveolar bone, providing an additionallayer of protection. Therefore, even in fires wheretemperatures approach 1600°F, teeth are ordinarilyfound intact within the oral cavity and can be used forID when all other means have been destroyed. Inaddition to the teeth, the materials used for dentalrestorations are also resistant to destruction by theenvironment, even more so than the natural teeththemselves. Gold alloys, as shown in figure 10-6,fused porcelain, synthetic porcelain, and porcelaindenture teeth all will withstand temperaturesexceeding 1600°F. Silver amalgam, the mostcommonly used restorative material, will resisttemperatures up to 1600°F.
Large Number of Potential Points ofComparison
The human dentition is composed of 32 teeth, eachof which may be restored, unrestored, or missing.When restored, any of the 5 different surfaces may beinvolved in the restoration. The number of potentiallydifferent dental chartings, considering even onerestorative material, is astronomically large (1 x 1048).In addition to restorations, the tooth crown form, root
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Figure 10-5.—Charred teeth.
Figure 10-6.—Gold fixed partial denture from a fire.
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canal, and root form provide numerous other potentialpoints of comparison that make each set of teethunique. Therefore, it can be said with completeconfidence that, given sufficient data, no two sets ofteeth are identical.
Antemortem Database
A decided advantage of dental ID over fingerprintID is the relatively comprehensive nature of theantemortem database. An extremely high percentageof the general population has visited the dentist at sometime in their life. Dentists routinely create dentalrecords for these patients that detail the antemortem(before death) dental condition. These records areoften maintained for long periods of time. Mostimportantly, dental radiographs are generated onalmost every patient. Radiographs are hard evidencethat is not subject to human error to the same extent thata written dental record might be. The radiographs alsoprovide multiple additional potential points ofcomparison for establishing ID. With adequate dentalrecords available to the forensic dentist, nearly 100%of unknown remains can be identified.
PROBLEMS IN DENTALIDENTIFICATION
The dentist and you, the Dental Technician, mayencounter many problems with dental ID. Theseproblems can waste numerous hours or days before thefinal determination of ID.
Illegible Dental Records
Because in many cases the dental records arehandwritten, the task of determining what treatmenthas been provided can be quite difficult.
Inadequate Dental Radiographs
Radiographs may not be found useful forcomparison purposes for a variety of reasons. Mostoften this is because of poor quality of the radiographobscuring the features necessary for comparison. Itmay also be because of a lack of positioning of theradiograph or absence of a date on the radiograph.
Lack of Adequate Charting
Many civilian dentists do not record the status ofthe dentition at the first appointment as required in theNavy. Pre-existing restorations, therefore, may not be
Dentists might use multiple systems to record thetreatment provided for a patient and to indicate whichtooth was treated. Unless the forensic dental team isfamiliar with every possible charting and numberingsystem, a dental record may be unintelligible despitebeing legible. Luckily, most of the civilian and Navydentists use a single system for charting andnumbering teeth in the United States.
Changes in Dentition
Teeth are not fixed in the jaws. Small changes inposition are constantly occurring in addition to thenormal functional wear produced by chewing. Thesechanges are not distinct over a short period of time, butover an extended time period these small changes canaccumulate to produce significant differences.
Human Error
No matter how conscientious and persistent adentist or Dental Technician might be about theaccuracy of their dental records, errors in the writtenrecord will occur on occasion. This can causediscrepancies in the comparison and problems inestablishing the ID.
PRINCIPLES OF DENTALIDENTIFICATION
The principles of dental ID are identical to thoseused in any other ID method. The postmortem (afterdeath) remains are examined and documented, then theantemortem records are obtained and reviewed, andfinally the two are compared to establish similaritiesand discrepancies. In evaluating the comparison, theforensic dental team looks first at discrepancies.Discrepancies are more important than similaritiessince a single discrepancy can negate a whole list ofsimilarities. It is important for the dental team toconsider the source of the discrepancy. If thediscrepancy is found in the written dental record, itmay be possible to explain it on the basis of humanerror. However, if the discrepancy is in a radiographiccomparison, it is extremely difficult to ignore.Discrepancies may be classified into two broadcategories, relative and absolute.
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documented in the dental record, leading to confusionin the final analysis.
Lack of Uniformity of Charting andNumbering Systems
Relative Discrepancies
These represent differences between the antemortemand the postmortem dental exam findings that can beexplained by continued dental treatment. For example,an unrestored tooth may have been restored in the timeinterval between the last dental record entry and thedeath of the individual. Or, a small restoration may beenlarged because of additional decay. In any case,these discrepancies do not necessarily negate anidentification if there are enough similarities in theremaining evidence.
Absolute Inconsistencies
These represent differences between the antemortemrecords and the postmortem exam findings that arephysically impossible and prove the remains cannot bethose of the individual under consideration. Forexample, an unrestored tooth is found in the unknownremains. On examination of the antemortem records,however, the radiographs reveal the tooth in questionhad previously been restored. Since natural toothstructure can never be replaced once it has beenrestored, this finding would verify that the remainswere not of those of the suspect individual.
Once discrepancies have been examined, thedental team will compare the number and degree of anysimilarities found in comparing the antemortem andpostmortem records. No minimum number ofsimilarities are required or accepted for positive ID. Inmany cases a judgment decision on the part of theexaminer may be required regarding the certificationof the ID.
RADIOGRAPHIC COMPARISONS
At some point in the ID process, as shown in figure10-7, the dental team will use dental radiographs andcompare with the dental remains of the deceased.There are four categories in radiographic comparison.
Exact Match
The postmortem radiographs show a restorationthat in every respect is identical to a restoration in thesame tooth in the antemortem radiographs as shown infigure 10-8. In some cases, the radiographs may be laidon top of each other to compare. Multiple distinctivepoints of comparison are normally documentable in asingle restoration.
Figure 10-7.—Forensic dental team comparing dental remains with radiographs.
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Figure 10-8.—Postmortem and antemortem exact match periapical X-ray.
Similarity which the antemortem and postmortem radiographswere exposed.
The restoration in the postmortem radiographs isnot identical to the restoration seen in the ante-mortem radiograph. The restorations occupy thesame position in the tooth and many similarities inform are present, but there is no exact match.Similarities are caused by differences in the angulation at
Relative Discrepancy
A significant difference exists between therestorations in the antemortem and postmortemradiographs. Little or no similarity can be found
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between them. However, the difference is explainable
by continued treatment and no absolute inconsistency
is present.
Unidentified
Absolute Inconsistency
A significant difference between restorations or
teeth in the antemortem and postmortem radiographs
are presented that are not explainable by continued
treatment. In fact, they are found to represent an
impossibility in treatment.
CLASSIFICATION OF THE DENTALIDENTIFICATION
Classification is the last and most important step in
the dental ID process. Five classifications can be used
to establish identity.
Positive Identification
The forensic dentist is positive they havedetermined the identity of the individual. Radio-graphic comparisons have been used in the ID process.
Positive Identification byCharting Only
The forensic dentist feels confident in identifying
the individual, but radiographic comparisons have not
been used in the ID process. The ID is based solely on
the written dental record. This category of ID leaves
open the possibility that errors in the written dental
record may be present and could affect the ID process.
Consistent With
A good probability is the remains are those of the
suspect individual. However, the findings are such
that the forensic dentist is not confident enough to
certify the remains. In this situation there is usually a
deficiency in either the antemortem or postmortem
evidence with which to make a comparison. It may
also be because of a lack of similarities or because of
the presence of too many discrepancies.
Exclusion
Absolute inconsistencies are present. The remains
cannot be those of the suspect individual.
No sufficient evidence exists to determine theidentity of the remains. While it could possibly be thesuspect individual, it could just as easily not be theindividual. Additional information, either antemortemor postmortem, is required before an identification canbe established.
MANAGEMENT OF MASS CASUALTYOPERATIONS
Although each mass casualty operation is uniquein many ways, some basic principles are common to allsuch missions. First and foremost is recognition thatthese operations require a team effort by allparticipating parties. Figure 10-9 shows the forensicteam receiving a victim to start the ID process.
While many specialty areas may be represented,all must work together and exchange information if theoperation is to be a success. For our purposes, we willdivide the participants into members of command/support elements or members of identificationelements. The command/support elements consist ofthe following:
Commander Facilities support
Public affairs
Communications Storage/handling
Regis t a r Mortuary affairs
Data processing
Security
Graves registration
Recovery/transportation
The identification elements consist of the following:
In processing
Photographic
Personal effects
Finger/foot print
Medical radiology
Dental
Medical exam/lab
Anthropology
Facial reconstruction
THE DENTAL TEAM IN MASSCASUALTY OPERATIONS
Like the other elements of the operation, thedifferent sections of the dental team work togetherwith a common goal. The basic steps in forensic dentalidentification are (1) postmortem examination and
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charting, (2) antemortem record acquisition and recordreconstruction, and (3) antemortem and postmortemrecord comparison. The dental elements of the teamare described next.
DENTAL TEAM LEADER
The dental team leader (dental officer) performsthe same tasks as the operations chief, only withinthe confines of the dental team. He brings backinformation to the dental sections and takes inform-ation to the operations commander and other membersof the ID operation.
DENTAL REGISTRAR
The registrar is one of the most important membersof the dental element because he must control andprotect all dental evidence coming into and going outof the dental area. He logs in and out all evidence,antemortem and postmortem, keeps track of workloadfigures (IDs per day, X-rays taken, photographs made,etc.), and coordinates with other areas of the operationto ensure that all potentially valuable sources of dentalinformation are made available for review by the
Figure 10-9.—Receiving a victim.
dental officer or dentist. Figure 10-10 shows a dentalregistrar updating a forensic tracking board. He makesparticular efforts to coordinate with personal effects,medical radiology, and medical examination sectionsand keeps the operations registrar updated withinformation the dental section needs. He alsomaintains and updates the dental exclusion matrix foruse at the close of the operation.
ORAL SURGERY
The surgeon's primary job, if needed, is to exposemaxilla and mandible so that the postmortemexamination team can examine and chart the dentalarches. Figure 10-11 shows a maxilla and mandiblethat have been completely removed from a casualty.This is accomplished by removing tissue from aroundthe oral cavity to expose the teeth, sectioning the ramusof the mandible and the pterygoid muscle to allow therelease of the lower jaw. Also, making an incision inthe floor of the mouth will release the mylohyoidmuscle to ensure an accurate anatomical placement ofthe dental films. This is made by the Dental Technicianwho will take radiographs of the appropriate areas.
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Figure 10-10.—Dental registrar.
DENTAL RADIOLOGY
Postmortem dental radiology plays a critical rolein the process of identifying unknown human remains.The procedures used are basically identical to thosethat would be performed on a living patient, withcertain adaptations necessary to each specificsituation. The actual exposure of postmortemradiographs poses some special problems that must berecognized and considered to ensure the production ofadequate, useful radiographs for comparison with theantemortem dental records. These problems will varydepending on the number of remains to be identified,the condition of those remains, the completeness of thedental structures recovered, and the availability ofantemortem dental records. In general, the smaller thetotal number of remains to be processed, the fewerproblems with postmortem radiology. As the numberof remains increases, the problems encountered inperforming postmortem radiology will increase bothin total number and complexity.
Access
Access to dental structures for placement andexposing of the radiographs is entirely determined bythe condition of the remains. Normally no problems
are associated with skeletalized remains. The lack ofsoft tissue allows easy visualization for placement of
film and angulation. Positioning of the tubehead canalso be readily determined and adjusted as needed.The same is true for fragmented remains, which areeasily positioned against the X-ray film on a flatsurface, as shown in figure 10-12.
Problems with access to dental structures arisemost commonly with intact full body remains. This isparticularly true if it is a recent death and rigor mortis(stiffing of a dead body) is still present. Opening the
jaws more than just a few millimeters can beexceedingly difficult in the presence of rigor mortis.Problems with access are also routinely encountered inindividuals killed by fire, because of the loss offlexibility of the muscle fibers as they are cooked in theextreme heat. Drowning victims will also presentproblems with access to the dentition. If the individualremained in the water for a prolonged period of time,the soft tissues around the teeth begin to swell withfluid and thereby obstruct accurate film placement.When access to the dentition for postmortem dentalradiology is a problem, the dental officer will be able toassist you with proper access.
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Figure 10-11.—Exposed maxilla and mandible.
Equipment
In small operations with minimal number of
remains to be processed, equipment is not a major
consideration. However, as the number of remains
increases, the availability of equipment becomes a
major determining factor in the efficiency of the dentalId section. In situations where hundreds of remains
require ID, you should have as many X-ray machines
available as possible to speed up the initial processing
of the remains. Postmortem radiographs are obtained
will normally require approximately 20 minutes toexpose a complete series of postmortem radiographs.Therefore, a maximum of 3 sets of remains per hourcan be processed with a single X-ray machine. Careful
The forensic X-ray section must realize thatexposure of postmortem dental radiographs is the timelimiting step for the dental ID section as a whole. It
from regular floor-mounted, mobile endodontic, andportable military field types of dental X-ray units.
Exposure of Postmortem Radiographs
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Figure 10-12.—Positioning dental fragment on X-ray film for exposure.
planning is required to prevent confusion in the flowand tracking of the remains as they are processed.
The dental radiology section's job is to get, asnearly as possible, a full mouth series of periapicalradiographs. On occasion, the forensic dentist mayrequest occlusal and lateral jaw films. The propertechnique to use is to expose of the films in the properanatomical orientation to prevent overlap, shorting, orelongation of exposed dental films. This is necessarybecause the postmortem films will be compared withthe antemortem films that were exposed on a livepatient using appropriate anatomical placement andangulation. Always expose a full mouth series usingduplicate film packets even if areas appear edentulousor teeth are missing, fractured, or avulsed. Shootdifferent films at several angles and take care to exposeall fragments in their proper anatomical orientation. Itmay not always be easy to take X-rays of teeth becausepostmortem dental remains may be fractured. Thefollowing supplies may be needed to assist you inexposing radiographs: hemostats, gauze, clay, andrope wax.
Developing
Any X-ray developer can be used to processradiographs. The use of a daytime loader is
recommended to speed up the process. When multipleremains are being processed at the same time, thefollowing procedures are normally prescribed.
The entire series of postmortem radiographs isexposed before any has been developed.
The series is placed into a labeled carryingcontainer for transport to the developing area.
Each series is developed at a single developingsite or machine. Films from one series are neverseparated from one another for developing.
Mounting
In forensic dental operations, it is not importantwhich method is used for mounting periapical andbitewing X-rays, as long as the method selected isuniform. The raised dot on the film can be facing in orout. All postmortem radiographs should be mounted inthe same manner so there will be no confusion by theexaminers as to which side is which. The policy shouldbe well publicized so that everyone working in thedental ID section, not just those in the dental radiologysubsection, are aware of the standard.
FILM ACCOUNTABILITY.—One primaryarea of concern is the ability to determine, at any point
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in time, if a film is missing from the film mount. Thismight occur because of its falling out of the mount orbecause an examiner has purposefully removed it forsome reason. When dental evidence is incomplete anda complete series of postmortem radiographs has notbeen taken, there are two methods by which theexaminers know for sure what films are available fortheir use. The first, and best method, is to fill all holesin the mount with undeveloped, unexposed film onceall films from a set of remains are developed. Anexaminer who picks up a mount will immediatelynotice the green, opaque films in the mount and realizethat no radiograph is available for this particular area.If an empty space is present in any of the mountingslots, the examiner immediately knows that a film wastaken out of this site. The second method is to maintaina written inventory list of postmortem films exposedon each set of remains.
ELIMINATION OF ERRORS. —A routinemounting procedure is quite useful and involves takingthe following actions:
Have one viewbox per developer and co-locatethem so that loss of films in transport from developer toviewbox is not possible.
Use viewboxes that can be laid flat to preventdropping of films.
Orient all dots in the correct position.
Orient the entire series as it will appear in the
mount before actually mounting any films.
Remember whatever is in the center of the film
determines its position in the mount.
Have all series reviewed by a dental officer or a
dentist at the postmortem examination station for
correctness in mounting.
DENTAL POSTMORTEM EXAMINATION
The postmortem examination team you may be onis responsible for examining and charting the dentalremains to include the presence or absence of teeth,restorations, pathology, and any other feature thatmight be useful in the ID process. Figure 10-13 showsa forensic dental examination of a casualty.
The process starts with gentle cleaning of thedental remains with a tooth brush using sodiumhypochlorite (bleach) and hydrogen peroxide.Remember that incinerated (burnt) teeth are brittle andwill shatter if not handled carefully. Next, a teamprocess including either a team of three dentists or ateam of two dentists and a dental hygienist or a DentalTechnician, chart all dental evidence on a postmortemdental record form. Figure 10-14 is an example of acompleted postmortem dental record form.
Figure 10-13.—Forensic dental examination.
10-15
Figure 10-14.—Completed postmortem dental record form.
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The entire dental team must agree to be consistentin charting methods. This is a slow process and muchattention must be paid to details. Remember to checkand double check each step. The team will decidewhich charting system they will use. The differentbranches of the service and civilian dentists all usedifferent charting systems and abbreviations. TheManual of the Medical Department, chapter 6,desc r ibes the Navy ' s cha r t ing sys tem andabbreviations used to complete all dental informationfor the different forms used in forensic dentistry. Otherdental abbreviations used for charting, such as theComputer Assisted Postmortem Identification, may beused and will be covered later in this chapter underComputer Support. The use of a fiberoptic light isinvaluable in the examination process. The examinerbegins by evaluating tooth #1 and associatedradiographs. The second dentist on the examinationteam evaluates tooth #1 and confirms the findings ofthe first dentist. The recorder charts the findings oftooth #1 and all three members confirm the charting.Tooth #2 is examined and the process is repeated untilall 32 teeth have been charted. The approach isredundant, but errors are corrected as they are made.Charting should be done in pen, not pencil. Findings to
be recorded during the postmortem examination are asfollows:
Dental restorations
Missing teeth
Prosthetic appliances
Pathology
Unique anatomy
Age estimate
References to possible gender and racial group
Teeth missing because of the trauma of the mishapshould be specifically noted to avoid confusion overextracted or congenitally missing teeth. A prostho-dontist should be available to examine and describedental prosthetic appliances. In some cases, theappliance may have been specifically marked foridentification as shown in figure 10-15. It is wise tosolicit from the victim’s family study models or extraprosthetic appliances that may be available. Suchevidence is important in providing antemortem dataregarding ridge shape/size, rugae, and general oralanatomy. The antemortem dental record will becovered next.
Figure 10-15.—Maxillary denture with SSN embedded in acrylic.
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ANTEMORTEM DENTAL EXAMINATION
Another major section in forensic dentistryinvolves the antemortem dental record examination.Dentists, hygienists, and Dental Technicians caneffectively operate this section. The task of thissection will always be the most difficult in the entireforensic dentistry arena. They will be required todetermine who was involved in the disaster, locate andprocure all military or civilian dental records andradiographs, arrange for the delivery of thesematerials, and undertake the process of developing acomposite antemortem record for each victim for theevidence supplied. You may not have all existingantemortem dental records for the victim from outsidesources. This may lead to discrepancies in thean temor tem record and pos tmor tem recordcomparison. The quality, quantity, and variety ofdental record documentation of this antemortemevidence present the major obstacles in this section.Clearly, all antemortem evidence must be compiled toa single antemortem dental record form as shown infigure 10-16, to provide a composite antemortempicture. The latter (computer/description codescolumn) may be easily compared to the postmortemfindings recorded on a postmortem dental record ofsimilar format. Comparing dental records sent directlyfrom dental offices with a postmortem record is a nearimpossible task. At least two members of theantemortem dental record staff should review eachcomposite antemortem dental record as a qualitycontrol mechanism. Figure 10-17 shows a dental staffreviewing antemortem dental records. The completedantemortem composite form should also be qualitychecked against antemortem dental radiographs.
COMPUTER SUPPORT
In this day of data management and wordprocessing, computers can now play a major role inforensic dental ID. The software we use is called theComputer Assisted Postmortem Identification(CAPMI) referenced in figure 10-18.
The basic principle is one in which antemortemand postmortem databases are built using theinformation charted on the antemortem andpostmortem forms. These two databases are runagainst each other and the possibilities of matches areranked to produce a most likely identities list. This listis then used by the forensic team to assist in the final IDprocess. The list does not make an ID, but merelyminimizes the number of records that must be
compared manually by the team. The advantage isthat, instead of having to look at every record to make acomparison, the dental officer or dentist who isreviewing the record is initially guided to the mostlikely match. This is tremendously efficient and offersa significant savings in time. CAPMI may be installedeither on a portable or desktop computer. Yourcommand can obtain copies of CAPMI software andinstructions free of charge by writing to the followingaddress:
The DirectorArmed Forces Institute of PathologyAttn: AFIP-AMS14th & Alaska Ave, NWWashington, DC 30306-6000
ANTEMORTEM/POSTMORTEMRECORDS COMPARISON
The last section in the dental forensic ID processcompares the antemortem and postmortem records.Here the results of all previous work are seen. Armedwith the antemortem record and radiographs,postmortem record and radiographs, CAPMI printout(if used), and a summary sheet, the forensic team startsthe process of comparing records and films. The sizeof the section is dependent on the number of fatalities,since there is a requirement to place all postmortemdental records face-up on tables in numerical order fora comparison with the antemortem composite dentalrecords, as shown in figure 10-19.
After all postmortem dental records have beenplaced as described, the staff can systematicallycompare- the antemortem dental composite recordsas they are received with the postmortem dentalrecords placed on the table. This is done by handcarrying the composite antemortem record andwalk ing a longs ide the t ab les v i ewing thepostmortem dental records looking for a significantpoint of comparison, such as a crown on tooth #30.Once significant points of comparison are notedbetween the antemortem and postmortem dentalrecord forms, the radiographs of the respectiverecords can be reviewed and a possible matchestablished. Figure 10-20 shows dental teammembers reviewing radiographs.
If it is possible to determine the gender of thedisaster victims, it is possible to reduce the manualcomparison task by placing the postmortem records in
10-18
Figure 10-16.—Completed antemortem dental record form.
10-19
Figure 10-17.—Reviewing antemortem dental records.
numerical order on table by gender. Postmortem time. Figure 10-21 shows an example of a completed
records of children may also be individually managed. dental ID summary sheet.
To provide quality control, provide the team leaderof the forensic dentistry section the antemortem andpostmortem dental records of potential positive IDestablished by the staff. The leader must reconstructthe positive dental ID. A dental identification formthat summarizes the ID data can be completed at this
This form is a tool in the decision-making anddocumentation process. It is used to provide rapidanswers to questions when the team leader of theforensic dentistry section meets with the IdentificationCenter chief at which time evidence regarding eachcase is presented. Only after all sections have
10-20
Figure 10-18.—Computer Assisted Postmortem Identification (CAPMI).
presented their evidence and all inconsistencies havebeen explained or addressed should the IdentificationCenter chief sign the case out as a positive ID. Afterthe case has been signed out as a positive ID, theantemortem and postmortem dental records andassociated evidence should be combined with thesummary sheet into a single completed file. Theantemortem composite dental record should be placedin the completed file only if the full dentition waspresent with the remains or if all dental/oral fragmentshave been recovered. If this is not the case and anadditional oral fragment is recovered, thepostmortemfragment may go unidentified since the necessaryantemortem dental record was placed in the completedfile. This mistake is made in almost every disaster.Please avoid it! In the consolidation process, theantemortem and postmortem dental radiographs thatprovided the conclusive evidence of the positive dental
identification should be photographed. Thesephotographs or slides are indispensable for recordkeeping purposes and provide a superior method ofdisplaying the evidence in court.
EQUIPMENT, SUPPLIES, ANDFACILITIES
The fol lowing equipment, supplies, andfacilities as listed in Tables 10-1, 10-2, and 10-3 arerecommended for use in forensic dental operations.The items mentioned below are only a recommendedlist. Most of the equipment and supplies can bemaintained in a medium-size tackle box and canvasbags for immediate availability and easy transport tothe ID site. Your command should plan to add orsubtract items or change quantities according to yourlocal requirements.
10-21
Figure 10-19.—Postmortem dental records.
Figure 10-20.—Reviewing radiographs.
10-22
Figure 10-21.—Dental identification summary sheet.
10-23
Table 10-1.—Equipment for up to 50 casualties
DESCRIPTION QUANTITY
50 KVP Endo X-ray unit, portable, self-contained
Portable lead screens
X-ray badges
X-ray film processor, with daylight loader
Fiberoptic light
Surgical saw (autopsy)
Headlamps
X-ray view boxes
Slide duplicator
Extension cords, 50 ft
CAPMI software and computer
35mm camera
Camera with self-developing film
Security badges
File cabinets, 4 drawer
Tables or gurney carts
1
4
9
1
1
1
2
3
1
3
1
1
1
15
1
As needed
Table 10-2.—Forensic Dentistry Kit (Supplies)
DESCRIPTION QUANTITY
35mm film, 36 exposure
Paper pads
Identification forms:Postmortem, Antemortem, and Summary reports
Tags with string or wire
Manila envelopes for case records
Masking tape
Stapler with staples
Large felt tip markers
Felt tip pens (black ink)
Plastic denture bags
Pencils
Clip boards
Paper cups
10 rolls
1 0
100 each
125
100
2 rolls
2
1 2
1 2
1 box LG
1 box SM
2 boxes
1 0
1 box
10-24
Table 10-2.—Forensic Dentistry Kit (Supplies)—Continued
DESCRIPTION QUANTITY
Work gloves, leather
Scrub suits
Surgical gowns, disposable
Surgical gloves, sizes 7 1/2 & 8
Surgical mask
D e n t a l X - r a y f i l m , d o u b l e e x p o s u r e
Chemicals for film processing
Self-developing film
Magnifying glass
L o o p s
Sodium hypochlorite
Safety glasses
Flashlights
Handsaw
Straight and curved retractors
Scaple handles
S c a p l e # 1 0 , # 1 5 , # 2 0
Large scissors, surgical
Small scissors, surgical
Large hemostats
Mouth props, large and small
Tongue blades
Cotton applicators
Mouth mirrors
Explorers
Periodontal scalers
Cutting pliers
Straight pliers
Straight chisel
M a l l e t
Millimeter rule
Spatula, #7 wax
Disclosing solution
Hydrogen peroxide solution
4 pairs
20 pairs
3 0
3 boxes each
1 box
10 boxes
as needed
5 rolls
1
2
1 gallon
5
6
1
1 set
4
1 box each
2
2
4
1 each
1 box
1 box
1 2
1 2
3
1
1
1
1
3
1
2 bottles
1/2 gallon
10-25
Table 10-2.—Forensic Dentistry Kit (Supplies)—Continued
DESCRIPTION QUANTITY
4 x 4 sponges 10 boxes
Toothbrushes 20
Computer terminal paper 1 box
Ribbon for terminal printer 1
Occlusal X-ray film 1 box
Soap, antibacterial 6 bottles
Towels 10
Scrub brushes
Rubber aprons
5
10
Trash can liners 1 box
Table 10-3.—Office Facilities
Office facilities:
Room for antemortem records
Room for postmortem records
Postmortem exam area
Access to:
Copy machine/computer
Watts/DSN telephone lines
Refrigeration
10-26
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