IADR Abstract Archives
Pulp Chamber Analysis In Primary Molars Using Micro-CT: In Vitro
Objectives: Pulp chamber to crown ratio is larger in primary teeth than in permanent teeth. Therefore, clinicians have to be mindful to avoid pulpal insult when restoring primary teeth with full coverage crowns. This study sought to (i) use micro-computed tomography (micro-CT) to determine the positional relationship between crown contour and the pulp chamber and (ii) analyse three-dimensional reconstructions of the primary dentition to identify factors that are critical during cavity preparations of primary teeth.
Methods: Thirty-one primary molars were extracted from thirteen patients, then scanned using micro-CT and reconstructed using analysis software. The position of the pulp chamber in relation to the crown contour was measured in three dimensions. The distance from each pulp horn to its respective cusp tip was measured as well as from the pulp chamber to each tooth surface. One-way ANOVA and two tailed t-test were used for statistical analysis.
Results: The pulp horn to cusp tip distance (PHCD) was significantly different between cusps in maxillary second primary molars. The mesio-buccal PHCD was significantly shorter when compared to the mesio-lingual and disto-lingual regions (P<0.05). The disto-buccal PHCD was also significantly shorter than the disto-lingual region (P<0.05). Mesial and distal walls were significantly thinner than buccal and lingual walls in all tooth types (P<0.05) and lingual walls in mandibular primary molars are thinner than those in maxillary primary molars (P<0.05). Furthermore, PHCDs and wall thicknesses were significantly less in primary first molars compared to primary second molars (P<0.05).
Conclusions: In maxillary second primary molars, tooth structure thickness is reduced over the buccal aspects when compared to the palatal. PHCDs and wall thicknesses are also less in first primary molars when compared to second primary molars. Furthermore, mesial and distal walls are thinner in all tooth types and the lingual walls of mandibular molars are thinner than those of maxillary molars.
Methods: Thirty-one primary molars were extracted from thirteen patients, then scanned using micro-CT and reconstructed using analysis software. The position of the pulp chamber in relation to the crown contour was measured in three dimensions. The distance from each pulp horn to its respective cusp tip was measured as well as from the pulp chamber to each tooth surface. One-way ANOVA and two tailed t-test were used for statistical analysis.
Results: The pulp horn to cusp tip distance (PHCD) was significantly different between cusps in maxillary second primary molars. The mesio-buccal PHCD was significantly shorter when compared to the mesio-lingual and disto-lingual regions (P<0.05). The disto-buccal PHCD was also significantly shorter than the disto-lingual region (P<0.05). Mesial and distal walls were significantly thinner than buccal and lingual walls in all tooth types (P<0.05) and lingual walls in mandibular primary molars are thinner than those in maxillary primary molars (P<0.05). Furthermore, PHCDs and wall thicknesses were significantly less in primary first molars compared to primary second molars (P<0.05).
Conclusions: In maxillary second primary molars, tooth structure thickness is reduced over the buccal aspects when compared to the palatal. PHCDs and wall thicknesses are also less in first primary molars when compared to second primary molars. Furthermore, mesial and distal walls are thinner in all tooth types and the lingual walls of mandibular molars are thinner than those of maxillary molars.