Postmortem Dental Examination and Autopsy Protocol

The postmortem dental examination begins with review of the case history and any preliminary identification information before the examiner approaches the remains. Knowing the proposed identity, the approximate age, and the circumstances of death allows the examiner to anticipate what they are likely to find and to direct the examination efficiently.

Access to the dentition is straightforward in fresh remains: the lips and cheeks are retracted with dental mirrors or mouth props, and the oral cavity is examined systematically. When rigor mortis is present, a mouth prop inserted gradually will achieve enough opening for examination and radiography without forcing the jaw. Forced opening of a rigored jaw risks fracture and is unnecessary.

• Equipment: dental mirror, probe, and explorer; a portable or wall-mounted dental X-ray unit with periapical film or digital sensor; a bitewing tab or positioning device; a camera for clinical photographs; and a portable light source. A standard dental chart form using the chosen notation system.
• Sequence: clinical photograph the oral cavity before disturbing anything. Document teeth present and their general condition. Record restorations, surface by surface, for each tooth. Then proceed to radiography. Photograph again after radiography if any manipulation has been performed.
• Chain of custody: if any teeth are removed for examination, each is bagged, labelled with tooth number, case reference, and date, and signed into the evidence record. A loose tooth found in the oral cavity or on the body surface is treated as potential evidence before it is treated as a dental specimen.

In most cases the dentition can be adequately examined and radiographed without removing the jaws from the body. Resection becomes necessary when decomposition has advanced to the point where tissue prevents adequate access, when fire damage has contracted surrounding tissue so severely that the oral cavity cannot be opened, or when radiographic quality from the intact body is insufficient for comparison purposes.

The procedure is performed with surgical saws, chisels, and rongeurs, removing the mandible and if necessary the maxillary alveolus as surgical blocks that can then be positioned optimally for radiography. The body is restored as far as possible after the examination, and the resected structures are preserved in the case material. Written justification for resection and pathologist authorisation should be documented in the case record before the procedure begins.

The goal of postmortem dental radiography is to produce images that can be directly compared with antemortem radiographs. This means using the same formats where possible: periapical images for individual tooth and root detail, bitewing views for interproximal contact and bone height, and a panoramic image as an overview. Where the AM records consist only of panoramic images, postmortem panoramic radiography is the priority.

Positioning for postmortem radiography is more difficult than in a clinical setting because the patient cannot cooperate. Film or sensor holders must be adapted, and exposure settings adjusted for the tissue overlying the teeth. In unresected remains, the X-ray tube is brought to the body; in resected blocks, the blocks can be positioned freely on a bench or a standard dental film holder, which typically produces better image geometry.

Decomposed remains present the most variable and demanding examination conditions. Early decomposition, within a few weeks in a temperate climate, typically allows examination after soft tissue removal or dissection. Advanced decomposition or skeletonisation means the odontologist works with dry or nearly-dry dental structures, often with loose teeth that have separated from the sockets.

• Tooth stability: in decomposed remains, periodontal ligament breakdown means teeth may be loose or absent. Each tooth found loose or separated must be documented in relation to where it was recovered. An upper-right molar found in the oral cavity should be assigned to its socket before the chart is written.
• Socket assessment: the condition of an empty socket indicates when the tooth was lost. A fresh socket with sharp margins and no bone remodelling suggests perimortem or postmortem loss. A smooth-walled, partially remodelled socket suggests antemortem loss months to years before death. This distinction is critical for comparing against AM records.
• Maceration: simmering heavily decomposed material in water removes residual soft tissue and allows cleaner examination and better radiographic images. The process must be temperature-controlled to avoid damage to tooth structure and bone.
• Radiographic positioning: individual loose teeth can be positioned in wax or putty for periapical radiography. The image format is the same as an AM periapical, allowing direct overlay comparison.

Teeth are among the most heat-resistant tissues in the body. Dental enamel survives temperatures that incinerate bone, and this is one of the reasons dental identification is so frequently attempted in fire deaths, aircraft accidents, and large-scale disasters involving fire. But heat does change dental structures in ways the examiner must understand.

Handling burned teeth requires extreme care. Calcined teeth fracture when handled and must be supported or stabilised with consolidants before they can be moved. Radiography should be attempted before any manipulation. Photographs documenting the in-situ state before any handling are essential and cannot be recreated afterwards.

The postmortem dental examination produces a case record that must be complete, internally consistent, and signed. It will be reviewed by a second odontologist, may be subject to legal challenge, and will be retained as part of the permanent investigative record. The standard output includes:

• Dental chart: completed in a standardised notation system (FDI preferred in international work), noting each tooth present, each tooth absent with socket condition, all restorations with surface and material, and any pathology or distinctive features.
• Radiographic series: labelled with case reference, tooth designation, and date. Digital files stored in DICOM or equivalent format. Film radiographs mounted and labelled.
• Photographs: pre-examination intraoral overview, close-up photographs of distinctive features, and post-manipulation photographs if any teeth were moved during examination. Photographs are date-stamped and included in the case file.
• Narrative report: describing examination conditions, any special procedures (resection, maceration), significant findings, and any limitations that affected the examination.

INTERPOL DVI standards specify the yellow PM form as the international data collection instrument for postmortem dental findings. Where this form is used, the case record must also include the completed yellow form. Consistency with international standards allows PM data to be compared against AM data collected by a team in another country working from INTERPOL pink forms.