HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by O'Higgins, E. A. Articles by Lee, R. T. Search for Related Content PubMed PubMed Citation Articles by O'Higgins, E. A. Articles by Lee, R. T.

The Influence of Maxillary Incisor Inclination on Arch Length

Department of Orthodontics, King's Dental Institute, London SE5 9RW, UK

R. H. Kirschen, B.D.S., M.SC., F.D.S., M.ORTH., R.C.S. and R. T. Lee, B.D.S., F.D.S., M.ORTH., R.C.S.

Department of Orthodontics, The Royal London Hospital, London E1 1BB, UK

This ex vivo study was designed to investigate Andrew's hypothesis that there is a space implication when incisors are torqued correctly. A working model was constructed to allow acrylic typodont incisors of varying known values of inclination to be substituted into the model. The arch lengths of the various 'set-ups' were measured using a reflex microscope linked to a PC. In order to quantify the space requirement of clinical relevance for adequate incisor torque, the method was repeated by substituting replicas of patients' 'natural' incisors.

For both acrylic and natural incisors it was found that, as the inclination of the teeth increased, there was an increase in all arch lengths, this being greater for the natural incisors. This larger increase for the natural incisors was related not only to their increased size, but was also dependent on the morphology of the incisor. Those incisors which were parallel-sided showed the greatest increase in arch length, whereas the incisors that were relatively triangular in shape showed the smallest increase.

When the inclination of an 'average' set of 21|12 is increased by 5 degrees, an increase in the arch length of approximately 1 mm may be expected.

Key words: Andrews' Six Keys, Space Analysis, Treatment Planning

Refereed Paper

This article has been cited by other articles:

				H. Wellens A clinical experimental simulation of changes in intercanine width associated with the correction of crowding: a pilot study Eur J Orthod, December 1, 2007; 29(6): 632 - 638. [Abstract] [Full Text] [PDF]

				E. A. O'Higgins and R. T. Lee How Much Space is Created from Expansion or Premolar Extraction? J. Orthod., March 1, 2000; 27(1): 11 - 13. [Abstract] [Full Text] [PDF]