Dentaoalveolar changes in young adult patients with Class II/1 malocclusion treated with the Herbst appliance and an activator

Abstract

Background/Aim. Functional appliances can be used effectively in the treatment of skeletal Class II/1 malocclusions. The best treatment results are obtained during active period of facial growth when skeletal, as well as dentoalveolar, changes occur. In comparison with removable functional appliances, such as activator, that are effective only during adolescent period of growth, the Herbst fixed appliance is also successful at the end of the growth period. It also offers a shorter treatment time and a patient compliance is not necessary. The aim of this study was to analyze and compare dentoalveolar changes in the group of young adult patients with Class II/1 malocclusion treated with the Herbst appliance and an activator. Methods. The sample for this study consisted of 50 patients of both sexes, 14-21 years of age with Class II/1 malocclusion. For estimating the effect of functional appliances used, the following cephalometrics parameters were determined: inclination of the upper and lower incisors, interincisal angle, antero-posterior molars relationships, overjet and overbite. The results obtained were statistically tested. Results. The cephalometric findings after the treatment indicated retroinclination of upper incisors (average value of 9°) and proclination of lower incisors (average value of 7°), mostly expressed in the patients treated by Herbst appliance (p lt 0.001). Increased overjet and distocclusion were completely corrected in the group of patients treated with the Herbst appliance, while the correction of malocclusion in the activator group was only partially accomplished. No changes in the overbite were noticed at the end of the treatment in both groups. Conclusion. The results of this study revealed that the Herbst appliance is more effective in the treatment of Class II/1 malocclusion in young adults in comparison with the activator.

Uvod/Cilj. Funkcionalni aparati uspešno se koriste u terapiji malokluzija klase II/1. Najbolji rezultati postižu se terapijom u periodu pubertetskog skoka rasta, kada su moguća najveća skeletna i dentoalveolarna pomeranja. U poređenju sa terapijom pokretnim funkcionalnim aparatima, kao što je aktivator prema Andresen-u, terapija Herbst-ovim fiksnim aparatom (Herbst aparat), uspešna je i nakon pubertetskog skoka rasta, vreme terapije je kraće, a bolesnike ne treba motivisati za saradnju jer je aparat fiksiran na zubima. Cilj istraživnja bio je da se kod bolesnika mlađeg odraslog uzrasta sa malokluzijom klase II odeljenja 1 uporede efekti fiksnog funkcionalnog Herbst aparata i pokretnog aktivatora na dentoalveolarne strukture. Metode. Ispitivanje je obuhvatilo 50 bolesnika sa malokluzijom klase II/1, oba pola, uzrasta 14-21 godine. Efekti primenjenih funkcionalnih aparata, aktivatora prema Andresen-u i Herbst aparata, procenjivani su na osnovu parametara merenih na profilnim telerendgenskim snimcima, nagiba gornjih i donjih sekutića, interincizalnog ugla, okluzije po Angle-u, incizalnog stepenika i incizalnog preklopa. Dobijeni rezultati obrađeni su statistički. Rezultati. Tokom terapije nastupile su statistički visokoznačajne promene u obe grupe: oralno naginjanje gornjih i vestibularno naginjanje donjih sekutića. Promene su bile izraženije u grupi bolesnika lečenih Herbst aparatom (p lt 0,001). Nagib gornjih sekutića promenjen je prosečno oko 9°, a donjih oko 7°. Odnos molara i incizalni razmak su u potpunosti korigovani na kraju lečenja u grupi lečenoj Herbst aparatom, dok su isti parametri u grupi sa aktivatorom bili nepotpuno korigovani. Nijedan od primenjenih aparata, na završetku lečenja, nije izazvao promene u vertikalnom preklopu sekutića. Zaključak. Poređenje terapijskih efekata Herbst aparata i aktivatora kod bolesnika uzrasta 14-21 godinu pokazalo je da je Herbst aparat efikasniji u korekciji dentoalveolarne malokluzije klase II odeljenja 1 nego aktivator.