Pulpal Status of Hypomineralized Permanent Molars

Author(s): Helen D. Rodd, BDS, PhD, et al
Journal: Pediatric Dentistry
Volume (number): 29(6)
Month, Year: Nov/Dec 2007
Major topic: Pulpal status of hypomineralized teeth
Type of Article: Scientific / research
Main Purpose: To determine the pulpal status of hypomineralized permanent first molars.
Overview of method of research: 25 sound and 19 hypomineralized permanent first molars were obtained from children requiring dental extractions under general anesthesia as part of an orthodontic treatment plan. Carious hypomineralized molars were excluded from the study. A total of 44 children, with a mean age of 9.4 years, provided the experimental teeth for the study. Only 1 tooth was collected from each child. Prior to tooth removal, children were interviewed to ascertain a simple pain history for both sound and hypomineralized teeth. The pulp sections were processed and immunostaining was performed using an indirect immunofluorescence method. Three different fields were subject to quantitative analysis: 1.) the MB pulp horn 2.) the occlusal subodontoblastic region between the 2 pulp horns and 3.) the midcoronal pulp region. The pulp sections were analyzed for pulpal innervation, pulpal vascularity, and the presence of immune cells.
Findings: Of the 19 hypomineralized samples, 6 had reportedly been sensitive, 5 had been asymptomatic, and for the remaining 8, a valid history could not be obtained. The pulp horn was the most densely innervated region and in the hypomineralized teeth there was evidence of an overall increase in neural density within the pulp horn and the occlusal subodontoblastic region. There was a marked increase in leukocyte common antigen-immunoreactive cells within the pulps of hypomineralized teeth exhibiting enamel loss. There were no significant differences in vascularity between sound and hypomineralized samples.
Key points/Summary: Some noncarious hypomineralized molars have an underlying pulpal inflammation. This histological presentation (increase in pulpal innervation, immune cell accumulation) is similar to that of carious permanent first molars in children of a similar age group. This may explain why children with hypomineralized teeth continue to experience pain with dental procedures even after the administration of local anesthetic.
Assessment of article: Thorough science, small sample size.