The Irregularity Index: A quantitative score of mandibular anterior alignment

doi:10.1016/0002-9416(75)90086-X

American Journal of Orthodontics

Volume 68, Issue 5, November 1975, Pages 554-563

https://doi.org/10.1016/0002-9416(75)90086-X Get rights and content

Abstract

A quantitative method of assessing mandibular anterior irregularity is proposed. The technique involves measurement directly from the mandibular cast with a caliper (calibrated to at least tenths of a millimeter) held parallel to the occlusal plane. The linear displacement of the adjacent anatomic contact points of the mandibular incisors is determined, the sum of the five measurements representing the Irregularity Index value of the case. Reliability and validity of the method were tested, with favorable results.

At the University of Washington, several clinical studies have been and are continuing to be performed, using this technique as one of several methods of assessing pretreatment status and posttreatment change. It is hoped that this article will aid the reader in understanding the rationale and utility of a simple quantitative tool which could be used in malocclusion assessment.

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Authors’ response
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^∗: Assistant Professor, Department of Orthodontics, School of Dentistry, University of Washington.

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Original articleThe Irregularity Index: A quantitative score of mandibular anterior alignment

Abstract

Handicapping labio-lingual deviations: A proposed index for Public Health purposes

Am. J. Orthod.

Orthodontic Treatment Priority Index

Handicapping malocclusion assessment to establish treatment priority

Am. J. Orthod.

The Occlusal Index: A system for identifying and scoring occlusal disorders

Am. J. Orthod.

Rating the characteristics of malocclusion: A systematic approach for planning treatment

Am. J. Orthod.

Developmental changes of the maxillary and mandibular dental arches

Angle Orthod.

Biometrics of crowding and spacing of the teeth of the mandible

Am. J. Phys. Anthropol.

Original article
The Irregularity Index: A quantitative score of mandibular anterior alignment