The relationship between Index of Complexity, Outcome and Need, and patients' perceptions of malocclusion: a study in general dental practice

Aim To examine the relationship between the Index of Complexity, Outcome and Need (ICON) and the subjective opinions of patients attending for routine dental care. Materials and methods This study was undertaken at two general dental practices in Cardiff and Bedford. 50 patients aged between 11-14 years and 50 patients aged 30-40 years presenting for routine dental treatment were selected in each. The subjects were assessed objectively using the ICON guidelines by two examiners trained and calibrated in the use of this index. The scores were recorded directly from the patient. Subjective assessments were obtained from the patients by means of a questionnaire consisting of four simple questions addressing aesthetics, function, speech and treatment need using a five point Likert scale. Results The mean ICON scores for the different genders and age groups participating in this study were; 11-14 year old males 58.4 (SE 3.17); 11-14 year old females 51.8 (SE 3.51); 30-40 year old males 51.2 (SE 2.70); 30-40 year old females 45.3 (SE 2.56). There were statistically significant differences in ICON scores between the younger and older groups (P = 0.024) and females and males (P = 0.04). Adult patients were more likely to reject treatment than younger patients. Analysis of the professional scores in relation to subjective assessments, using the Spearman rank correlation coefficient, for 11-14 and 30-40 year olds, and for the male and female genders, revealed that the ICON has a significant correlation with patients' perceptions of aesthetics, function, speech and treatment need (r(2) = 0.01 to 0.28). The only exceptions were patients' perceptions of speech in the 30-40 year old group, and function in the female gender, which did not show a statistically significant correlation to the professional assessments. Conclusion In this study, the ICON was found to correlate with patients' opinions of aesthetics, function, speech and treatment need. The strength of association, however, was low. It can be concluded that the ICON alone is not necessarily a suitable predictor for appearance, function, speech or treatment need for those individuals attending general dental practice for routine dental care. In combination with a simple question to assess the patients desire for treatment, the shared decision for any particular individual to enter the treatment process can be determined.