Abstract
PurposeTo assess a potential association between lower incisor (LI) position changes during Herbst–multibracket appliance (Herbst–MBA) treatment and the development of labial gingival recessions (LGR).MethodsAll class II patients (Department of Orthodontics, University of Giessen, Giessen, Germany) who had undergone Herbst–MBA treatment until 2015 with study models and lateral cephalograms available from before (T0) and after treatment plus ≥24 months of retention (T3) were included (n = 259). Lateral cephalograms were evaluated regarding LI position changes: iiL/ML (angle between LI long axis and mandibular plane [MP]), ii-MLPg (distance between LI incisal edge and a line perpendicular to MP through pogonion), apex-MLPg (distance between LI apex and a line perpendicular to MP through pogonion), ii-MLii (distance between LI incisal edge and MP on a line perpendicular to MP through incisal edge). Using study models the distance between the cementoenamel junction and the deepest point of the gingival margin was defined as LGR.ResultsThe following cephalometric mean changes were recorded (T0–T3): iiL/ML +5.9 ± 5.76° (p = 0.929), ii-MLPg −0.2 ± 0.25 mm (p = 0.430), apex-MLPg +0.1 ± 0.32 mm (p = 0.363), ii-MLii +0.1 ± 0.36 mm (p = 0.206). The mean increase of LGR magnitude measured on the study models was 0.1 ± 0.35 mm. However, no association with the cephalometric LI position changes was found (|R| ≤ 0.2).ConclusionThere is no association between the amount of LI position changes and the development of LGR during Herbst–MBA treatment plus retention. Nevertheless, individual predisposition or excessive treatment changes and extraordinary treatment approaches, respectively, might still lead to development of LGR.
Highlights
Labial gingival recessions (LGR) result in esthetic impairment but are associated with tooth hypersensitivity and a greater susceptibility to root caries [36].Since the 1970s it has been hypothesized that the development of LGR is a result of bone dehiscences after proclination of lower incisors [5, 34]
Previous investigations have already assessed whether Herbst treatment and the respective proclination of lower incisors is associated with LGR [7,8,9, 26, 31]
After obtaining ethical approval (No 80/14), the records of all class II patients who had been treated with a Herbst–multibracket appliance (MBA) at the study center (Department of Orthodontics, University of Giessen, Giessen, Germany) since 1986 were screened for the following inclusion criteria: Active treatment completed by 1 January 2015 Lateral cephalograms and unaltered study casts available from before treatment (T0) and after Herbst–MBA treatii ment plus ≥24 months of retention (T3); both records had to be taken at the same occasion (±0 months)
Summary
Since the 1970s it has been hypothesized that the development of LGR is a result of bone dehiscences after proclination of lower incisors [5, 34]. Protrusion and proclination of the lower incisors are side effects of Herbst treatment [12, 16, 17, 22, 24, 25, 27, 31]. Previous investigations have already assessed whether Herbst treatment and the respective proclination of lower incisors is associated with LGR [7,8,9, 26, 31]. In another study using cone-beam computed tomography to investigate whether Herbst treatment induces alveolar bone loss around the mandibular incisors, no statistically significant effects were found regarding the vertical alveolar bone level or the alveolar bone thickness [32]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
