Intraoral Photographs for Rating Dental Arch Relationships in Unilateral Cleft
Lip and Palate
Yu-Fang Liao, D.D.S., Ph.D., Chiung-Shing Huang, D.D.S., Ph.D., I-Feng Lin, Ph.D.
Background and Purpose: The Goslon Yardstick is one of the most
commonly used methods to assess dental arch relationships of patients with
unilateral cleft lip and palate. This system was originally applied to dental casts.
For reasons of economy and convenience, we aimed to determine whether
intraoral photographs could substitute for dental casts for rating dental arch
Methods: Records of 58 patients with nonsyndromic complete unilateral cleft
lip and palate from the Chang Gung Craniofacial Center, Taipei, Taiwan, were
used in this study. A set of dental casts and digital intraoral photographs taken
at around 9 years of age were available for all patients. An experienced
examiner rated the dental casts using the Goslon Yardstick to provide the
reference scores. The other three examiners rated the intraoral photographs
and repeated the rating 1 week later to calculate inter- and intraexaminer
reliability. The photographic scores for each examiner were then compared with
the reference scores to determine the validity of the photographs.
Results: The results showed no significant difference between the rating of
dental casts and photographs using the Goslon Yardstick. Reliability was also
high for rating on photographs.
Conclusions: Intraoral photographs appear to be a viable alternative to the
application of the Goslon Yardstick on dental casts.
KEY WORDS: dental arch relationships, Goslon Yardstick, intraoral photo-
graphs, treatment outcome, unilateral cleft lip and palate
In addition to speech, growth, appearance, and hearing,
a criterion for assessing treatment outcomes of patients
with clefts is occlusion (i.e., dental arch relationships). A
major means of evaluating occlusion is dental cast analysis.
In 1987, in an attempt to be simple and rapid, Mars and
coworkers implemented a rating system for occlusion of
children with unilateral cleft lip and palate (UCLP), the
Goslon Yardstick. The Goslon Yardstick is a rating system
specifically developed to grade dental arch relationships in
the late mixed or early permanent dentition into five
categories. This system assures reliability and reproducibil-
ity (Mars et al., 1992; Hathorn et al., 1996; Johnson et al.,
2000; Morris et al., 2000).
The Goslon Yardstick also has been successfully used in
studies discriminating the quality of the dental arch
relationships among different centers (Mars et al., 1992;
Mølsted et al., 2005). This makes the Goslon Yardstick a
useful tool for comparative cross-center studies. However,
for intercenter studies or studies that require ratings by
external examiners, the examiners, the dental casts, or both
must travel to the place at which the rating will be carried
out. This inevitably is associated with some expense and
inconvenience. For reasons of economy and convenience,
Nollet and coworkers (2004) recently tested the reliability
of rating dental arch relationships using the Goslon
Yardstick on dental casts and photographs of dental casts.
They demonstrated that no significant differences were
found between the rating of dental casts and photographs
of dental casts. Therefore, they concluded that photographs
of dental casts are a reliable alternative to the application of
the Goslon Yardstick on dental casts. Indeed, an assess-
ment method that could be performed over the Internet
would be cost effective. Although applying the assessment
to photographs of dental casts is cost effective, a more
economic and convenient approach would be to substitute
the photographs of dental casts with similar views of
intraoral photographs, due to the reduced need for
obtaining dental casts. The purpose of this study, therefore,
was to determine whether intraoral photographs could be
Submitted December 2007; Accepted December 2008.
Address correspondence to: Dr. Yu-Fang Liao, Department of
Dentistry, Chang Gung Memorial Hospital, 199 Tung-Hwa North Road,
Taipei 105, Taiwan. E-mail firstname.lastname@example.org.
Dr. Liao is Assistant Professor, Department of Dentistry, Chang Gung
Memorial Hospital, Taipei, Taiwan; and College of Medicine, Chang
Gung University, Taoyuan, Taiwan. Dr. Huang is Professor, Department
of Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan; and
College of Medicine, Chang Gung University, Taoyuan, Taiwan. Dr. Lin
is Associate Professor, Institute and Department of Social Medicine,
School of Medicine, National Yang-Ming University, Taipei, Taiwan.