Infundibula of equine maxillary cheek teeth: Part 2: Morphological variations and pathological changes.

The research article discusses the variations and pathological changes in the infundibula of equine maxillary cheek teeth. The study identified the developmental abnormality called infundibular cemental hypoplasia in over half the teeth and possible links to endodontic disease.

Explanation of the Study

• The researchers assessed 688 cheek teeth (CT) with no evidence of dental diseases and 55 diseased permanent, completely erupted upper CT at a macroscopic level. This was done by viewing the occlusal surface and horizontal sections of these teeth.
• The study also utilized methods such as porphyrin assays, which are used to detect residual blood in the infundibular cementum, a portion of the tooth structure.
• Selected tooth samples further underwent microscopic examination using routine and immunohistological staining techniques. The goal was to identify potential pathways for the spread of infectious agents from the infundibulum to the tooth’s endodontic system. An endodontic system refers to the inside of the tooth, including the root canal system.

Key Findings

• Infundibular cemental hypoplasia, a non-pathological developmental aberration, was detected in over 50% of the healthy teeth and in over 70% of the diseased teeth. This condition was most prevalent in the first molar, known as the Triadan 09.
• The study identified and defined an erosive condition affecting the infundibula of the teeth, naming it infundibular erosion. The condition was present in fewer than 6% of healthy teeth, but it was observed in more than 27% of diseased teeth, always in association with endodontic disease.
• The findings suggest that teeth with infundibular cemental hypoplasia are likely to develop destructive erosion, leading potentially to endodontic disease.
• Certain morphological factors were described that could support this hypothesis.

Additional Observations

• The researchers found residual blood in 74% of the infundibula studied, even in the absence of vital blood vessels. They speculate that this blood might remain after tooth eruption, creating a favorable climate for bacterial growth.
• Characteristics of the infundibular enamel were highlighted, including diverse infoldings and focal enamel aplasia in some areas. These physical features could facilitate bacterial settlement and the eventual spread of infectious agents from the infundibulum to the endodontic system.