Evaluation of Changes in the Occlusion and Occlusal Vertical Dimension in Children Following the Placement of Preformed Metal Crowns Using the Hall Technique

Objectives: To evaluate the time taken and the mechanism through which the occlusion settles following the placement of a preformed metal crown (PMC) using the Hall technique. The secondary objective was to assess any temporo mandibular joint dysfunction (TMD) resulting from the Hall technique through a questionnaire. Study Design: 44 children fulfilling the inclusion criteria were evaluated for changes in overbite and occlusal vertical dimension (OVD) following the placement of preformed metal crowns (PMCs) using the Hall technique. The overbite and OVD measurements were taken before treatment, immediately post treatment, then at one, two, three and four weeks post treatment. After four weeks, a questionnaire recorded the occurrence of any signs or symptoms of TMD. Results: At the fourth week, the overbite measurement did not show a statistically significant difference (p value= 0.58) compared to baseline values indicating that the occlusion settled by the fourth week. By the third week the OVD values obtained did not show a significant difference compared to the baseline (p value= 0.42) indicating that the OVD had been restored. The questionnaire provided at the end of four weeks showed negative response for signs and symptoms of TMD in all the children. Conclusion: Any changes in occlusion following the placement of a Hall crown settles in four weeks. The OVD settles three weeks post placement implying that extrusion of teeth do not play a role in settling of the occlusion. The children do not develop any signs or symptoms of TMD post a Hall crown.