Evaluation of agreement and correlation of three occlusal indices in an assessment of orthodontic treatment need

Abstract

Background/Aim. Occlusal indices are quantitative diagnostic indicators of malocclusion severity, orthodontic treatment need, complexity and outcome. The aim of this study was to determine correlations and agreement among three occlusal indices: the Index of Orthodontic Treatment Need (IOTN), the Peer Assessment Rating Index (PAR) and the Index of Complexity, Outcome and Need (ICON) in evaluating orthodontic treatment need. Methods. A total eighty study models of patients referred to the Department of Orthodontics, School of Dentistry, Belgrade, were assessed in this retrospective study. Malocclusions of various types and severity in the permanent dentition were included. Results. The Aesthetic and the Dental Health Component of IOTN determined orthodontic treatment need in 25% and 51% of the patients, respectively. PAR determined orthodontic treatment need in 59% and ICON in 53% of patients. The Aesthetic Component of IOTN and ICON had the highest correlation (Spearman's correlation coefficient 0.95, p lt 0.01). Correlations between indices were 0.44 to 0.61 with statistical significance (p lt 0.01). The agreement between indices, calculated using Kappa statistics, was 0.22 to 0.63. Conclusion. The most critical in malocclusion assessment was PAR. The Aesthetic Component of IOTN and ICON correlated highly (p lt 0.01). Correlations between other pairs of indices were moderate (p lt 0.01). The Aesthetic Component of IOTN and ICON had substantial agreement, whereas agreement between other indices was fair or moderate. ICON could replace PAR and IOTN. Application of occlusal indices enables objective evaluation of orthodontic treatment need and easier determination of the treatment priorities.

Uvod/Cilj. Okluzalni indeksi su kvantitativni dijagnostički pokazatelji težine malokluzije, potrebe za ortodontskim lečenjem, složenosti i rezultata lečenja. Cilj rada bio je da se utvrde korelacije i saglasnost između tri okluzalna indeksa: Index of Orthodontic Treatment Need (IOTN), Peer Assessment Rating Index (PAR) i Index of Complexity, Outcome and Need (ICON) u pogledu određivanja potrebe za ortodontskim lečenjem. Metode. U retrospektivnom istraživanju ocenjeno je 80 studijskih modela bolesnika Klinike za ortopediju vilica Stomatološkog fakulteta u Beogradu. Obuhvaćene su malokluzije različitog tipa i težine u stalnoj denticiji. Rezultati. Potreba za ortodontskim lečenjem utvrđena je estetskim i zdravstvenim delom IOTN indeksa kod 25% i 51% bolesnika, redom. Na osnovu PAR indeksa potreba za ortodontskim lečenjem utvrđena je kod 59%, a na osnovu ICON indeksa kod 53% bolesnika. Estetski deo IOTN indeksa i ICON indeks imali su najveću korelaciju (Spearman-ov koeficijent korelacije 0,95; p lt 0,01). Korelacija među ostalim indeksima kretala se od 0,44 do 0,61 i bila je statistički značajna (p lt 0,01). Saglasnost među indeksima, izražena Kappa koeficijentom, kretala se od 0,22 do 0,63. Zaključak. Indeks PAR najkritičnije ocenjuje malokluzije. Korelacija između estetskog dela IOTN indeksa i ICON indeksa veoma je izražena i statistički značajna (p lt 0,01). Korelacije između ostalih parova okluzalnih indeksa srednje su izražene i statistički su značajne (p lt 0,01). Estetski deo IOTN indeksa i ICON indeks imaju odličnu saglasnost, dok je kod ostalih indeksa saglasnost dobra ili vrlo dobra. Indeks ICON mogao bi da zameni indekse PAR i IOTN. Primena okluzalnih indeksa omogućava objektivnu procenu potrebe za ortodontskim lečenjem i olakšava određivanje prioriteta u lečenju.