Thin-plate spline graphical analysis of the mandible in mandibular prognathism

Hsin Fu Chang, Hong Po Chang, Pao Hsin Liu, Chih Han Chang

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The chin cup has been used to treat skeletal mandibular prognathism in growing patients for 200 years. The pull on the orthopedic-force chin cup is oriented along a line from the mandibular symphysis to the mandibular condyle. Various levels of success have been reported with this restraining device. The vertical chin cup produces strong vertical compression stress on the maxillary molar regions when the direction of traction is 20° more vertical than the chin-condyle line. This treatment strategy may prevent relapse due to counter-clockwise rotation of the mandible. In this report, we describe a new strategy for using chin-up therapy involving thin-plate spline (TPS) analysis of lateral cephalometric roentgenograms to visualize transformation of the mandible. The actual sites of mandibular skeletal change are not detectable with conventional cephalometric analysis. A case of mandibular prognathism treated with a chin cup and a case of dental Class III malocclusion without orthodontic treatment are described. The case analysis illustrates that specific patterns of mandibular transformation are associated with Class III malocclusion with or without orthopedic therapy, and that visualization of these deformations is feasible using TPS graphical analysis.

Original languageEnglish
Pages (from-to)790-794
Number of pages5
JournalJournal of the Formosan Medical Association
Volume101
Issue number11
Publication statusPublished - 2002 Nov 1

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Medicine(all)

Cite this