Comparison of external apical root resorption and repair levels induced by PowerScope and Forsus fatigue resistant device appliances: Retrospective cohort study with long-term follow-up Vergleich der durch PowerScope- und Forsus-Fatigue-resistant-Apparaturen induzierten externen apikalen Wurzelresorption und Regenerationsgrade: Retrospektive Kohortenstudie mit langfristigem Follow-up
Journal of Orofacial Orthopedics, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s00056-026-00647-9
- Dergi Adı: Journal of Orofacial Orthopedics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, EMBASE, MEDLINE, Biomedical Reference Collection: Corporate Edition (EBSCO)
- Anahtar Kelimeler: Class II malocclusion, Fixed functional appliances, Molars, Orthodontic treatment, Root resorption
- Hacettepe Üniversitesi Adresli: Hayır
Özet
Purpose: To assess the impact of PowerScope (3M Unitek Corp., Monrovia, CA, USA) and Forsus fatigue resistant device (FRD; American Orthodontics, Sheboygan, WI, USA) appliances on orthodontically induced external apical root resorption (OIEARR) and repair amounts in the maxillary and mandibular posterior teeth. Methods: This study involved 39 patients treated for Angle class II malocclusion using either PowerScope (n = 20) or Forsus FRD (n = 19). A total of 546 roots were evaluated after calculating a magnification coefficient for each tooth. The lengths of maxillary and mandibular premolars, and the mesial and distal lengths of first molars were measured and compared pretreatment (T0), posttreatment (T1), and retention (T2). Results: The mean retention period was 39.8 months. Significant OIEARR was noted at T1 across almost all evaluated teeth compared with T0, while most of the teeth also demonstrated significant repair at T2 relative to T1. However, the lengths at T2 remained significantly shorter than those at T0. OIEARR was significantly greater, particularly for teeth 1.6, 2.6, 3.6, 2.4, and 4.5 in the Forsus FRD group (median values: 0.6–1.5 mm) compared to the PowerScope group (median values: 0.4–1.1 mm). For example after Forsus FRD treatment, the mesial roots of teeth 1.6 and 2.6 shorten by 1.4 mm and 1.5 mm, respectively. Although repair was observed in both groups, teeth in the Forsus FRD group exhibited significantly shorter lengths at T2 than at T0. Conclusion: Almost all teeth treated with fixed functional appliances experienced OIEARR, and repair was observed during retention. However, teeth in the Forsus FRD group, particularly the maxillary molars, showed a greater reduction in length.