Prevalence of KIG-grades 3-5 in an orthodontic practice in North Rhine Westphalia compared with results of the DMS•6 and with KZBV data.

Background And Aim: The prevalence of tooth and jaw malocclusions in 8- to 9-year-olds was surveyed in a nationwide setting as part of the orthodontic module of the Sixth German Study on Oral Health (DMS•6), using the orthodontic indication groups (KIG) as index. Aim of this study was the detection of the prevalence of malocclusions requiring treatment according to the KIG index in statutorily insured patients of an orthodontic practice in North Rhine Westphalia, Germany, and to compare results with corresponding DMS•6 and KZBV data.

Patients And Methods: Between 2017-2021, n = 953 statutorily insured patients called for an initial consultation and subsequent determination of the KIG-classification and -grades. The malocclusions were classified and graded in the highest possible KIG-grade according to valid SHI guidelines. Multiple classifications were not recorded. KIG-grade > 3 according to the valid guidelines was detected in n = 815 patients. Since the DMS•6 does not contain information on KIG classifications "U" and "S", their inclusion was waived despite evaluation, leaving data from n = 683 patients for analysis and comparison.

Results: During the study period, n = 235 patients (34.4%) had KIG-classification "D". More than 10% were classified as "K" (120 patients, 17.6%), "P" (98 patients, 14.2%), "M" (89 patients, 13.0%), and "E" (81 patients, 11.9%). Of 16 possible classifications with KIG-grade > 3, "D4" was the most common with 26.6% (182 patients). The results confirm the findings from the multicentric DMS•6 from2021 and corresponding KZBV data from 2020.

Conclusions: Sagittal deviations described by classifications "D" and "M" represent with 47.4% almost half of the malocclusions with treatment need. KIG-grade D4 is the most frequent classification. There were no regional deviations of the prevalence of KIG-grades 3-5 in the district of Viersen / North Rhine compared with the national average, not even when scrutinizing a five-year-period.