The Herbst appliance is an orthodontic appliance used by orthodontists to correct class 2 retrognathic mandible in a growing patient, meaning that the lower jaw is too far back. This is also called bitejumping. Herbst appliance parts include stainless steel surgical frameworks that are secured onto the teeth by bands (steel rings that go around teeth) or acrylic bites. These are connected by sets of telescoping mechanisms that apply gentle upward and backward force on the upper jaw, and forward force on the lower jaw. The original bite-jumping appliance (Herbst appliance) was designed by Dr. Emil Herbst and reintroduced by Dr. Hans Pancherz using maxillary and mandibular first molars and first bicuspids. The bands were connected with heavy wire soldered to each band and carried a tube and piston assembly that allowed mandibular movement but permanently postured the mandible forward.[1] The appliance not only corrected a dental Class II to a dental Class I but also offered a marked improvement of the classic Class II facial profile.[2]
History
editIt was developed by Emil Herbst in the early 1900s[3] and was reintroduced in 1979 by Hans Pancherz, it is largely established in today's orthodontics for Class II therapy.[4] Many designs of this appliance have since been developed such as Sabbagh Spring, Powerscope, and Cantilever Bite Jumper (CBJ)
Mechanism of Action
editThe Herbst appliance serves as an effective solution for correcting a class II malocclusion, where the lower jaw is positioned too far back in relation to the upper jaw. To address this misalignment, the Herbst appliance is typically affixed to the last molar on the upper teeth and the first premolar on the lower teeth. Attachment methods may include bands, acrylic bites, or stainless steel crowns. Central to its function is a telescoping rod that permits the patient to open their mouth, while maintaining a fixed distance when closed. This fixed retraction pushes the lower jaw forward and repositions the upper arch, thereby rectifying the bite issue. The appliance's gradual adjustment mechanism also facilitates tooth movement, with the rod exerting pressure to push the upper teeth backward and the lower teeth forward. Orthodontists may incorporate bushings to extend the fixed length of the rod, aiding in the progressive correction of the malocclusion.[5]
Modifications
editThere are 4 major modifications in the design of Herbst appliances known as Herbst 1, Herbst 2, Herbst 3 and Herbst 4. There are several variants of the Herbst appliance, including cast Herbst appliance and acrylic splint Herbst appliance.[6][7] Some of the other variations include;
- Utilization of a Herbst appliance with a ball joint for cases requiring larger lateral movements, facilitating enhanced jaw mobility.
- Seamless integration of the Herbst appliance with a palatal expander to widen the upper arch and optimize orthodontic outcomes.
- Implementation of a lower archwire to exert pressure on all lower teeth, rather than just one, to improve grip and treatment efficacy.[5]
Indications
editThe Herbst appliance is indicated for the noncompliant treatment of Class II skeletal malocclusions with retrognathic mandible [8] b) and in high angle patients due to the increase in sagittal condylar growth, c)in patients with deep anterior overbite d)in cases of mandibular midline deviation e) n mouth breathers due to the lack of interference while breathing.[9]
The removable Acrylic Herbst Appliance can also be used in patients suffering from obstructive sleep apnea, in order to improve the clinical symptoms. Herbst treatment is also good in postadolescent patients who have passed their peak pubertal growth, as the appliance can take advantage of the residual growth.[10]
Treatment timing
editThe appropriate skeletal maturation period to initiate Herbst treatment is considered as a critical parameter for successful results. Herbst treatment before the pubertal peak of growth has led to a normal skeletal and soft tissue morphology at a young age. However, this early approach needs retention of the treatment results until the eruption of all the permanent teeth into a stable relationship. By starting treatment in the permanent dentition at or just after the pubertal growth peak, the larger increase in the condylar growth and the shorter retention phase required have led to a more stable occlusion and reduced posttreatment relapse. However, some researchers have found that Herbst treatment was giving equal results in prepubertal and postpubertal patients although greater anchorage loss is to be anticipated in postpubertal patients.[11]
Advantages
edit- Continuous 24-hour functionality of the Herbst appliance leads to shorter treatment durations, typically lasting 6 to 8 months, compared to 2 to 4 years with removable alternatives.[12]
- Elimination of the need for patient compliance due to the fixed nature of the appliance, reducing the risk of treatment interruptions and enhancing overall effectiveness.[5]
- Promotion of proper jaw alignment by the Herbst appliance can help prevent the need for tooth extractions and improve the patient's facial profile as the jaw moves forward.[5]
- Customizable design allows for modifications tailored to individual patient needs, contributing to enhanced patient tolerance and treatment outcomes.[5]
Disadvantages
edit- Potential for undesired spacing in the upper arch as teeth are repositioned during treatment with the Herbst appliance.[5]
- Initial discomfort or difficulty chewing may be experienced by patients during the first few weeks of wearing the appliance, though this typically resolves as they acclimate to its presence.[5]
Treatment Time
editThe duration of treatment with a Herbst appliance can vary depending on the severity of the case, but typically ranges from 6 to 8 months. In instances of more pronounced underbites, treatment may extend to as long as a year.[12]
References
edit- ^ Mayes, Joe H. (2006-01-01), Papadopoulos, MOSCHOS A. (ed.), "CHAPTER 5 - The Cantilever Bite Jumper (CBJ)", Orthodontic Treatment of the Class II Noncompliant Patient, Edinburgh: Mosby, pp. 59–68, doi:10.1016/b978-0-7234-3391-0.50010-0, ISBN 978-0-7234-3391-0, retrieved 2023-02-14
- ^ Pancherz, H.; Anehus-Pancherz, M. (1982-02-01). "The effect of continuous bite jumping with the Herbst appliance on the masticatory system: a functional analysis of treated Class II malocclusions". The European Journal of Orthodontics. 4 (1): 37–44. doi:10.1093/ejo/4.1.37. ISSN 0141-5387. PMID 6950902.
- ^ Yang, Xin; Zhu, Yafen; Long, Hu; Zhou, Yang; Jian, Fan; Ye, Niansong; Gao, Meiya; Lai, Wenli (June 2016). "The effectiveness of the Herbst appliance for patients with Class II malocclusion: a meta-analysis". The European Journal of Orthodontics. 38 (3): 324–333. doi:10.1093/ejo/cjv057. ISSN 0141-5387. PMC 4914909. PMID 26306822.
- ^ Pancherz H. Treatment of class II malocclusions by jumping the bite with the Herbst appliance. A cephalometric investigation. Am J Orthod. 1979;76(4):423–42. doi:10.1016/0002-9416(79)90227-6.
- ^ a b c d e f g Papadopoulous, Moschos A. (2015). "Skeletal Anchorage in Orthodontic Treatment of Class II Malocclusion". Science Direct. Retrieved 21 February 2024.
- ^ Howe, Raymond P. (December 1982). "Palatal expansion using a bonded appliance". American Journal of Orthodontics. 82 (6): 464–468. doi:10.1016/0002-9416(82)90313-x. ISSN 0002-9416. PMID 6760723.
- ^ McNamara, James A.; Howe, Raymond P. (August 1988). "Clinical management of the acrylic splint Herbst appliance". American Journal of Orthodontics and Dentofacial Orthopedics. 94 (2): 142–149. doi:10.1016/0889-5406(88)90362-9. ISSN 0889-5406. PMID 3041796.
- ^ The Herbst appliance; Hans U. Paulsen, Moschos A. Papadopoulos, in Orthodontic Treatment of the Class II Noncompliant Patient, 2006
- ^ Bock, N.; Ruehl, J.; Ruf, S. (2017-12-08). "Orthodontic Class II:1 treatment—efficiency and outcome quality of Herbst-multibracket appliance therapy". Clinical Oral Investigations. 22 (5): 2005–2011. doi:10.1007/s00784-017-2294-9. ISSN 1432-6981. PMID 29222594. S2CID 254087354.
- ^ Cançado, Rodrigo Hermont; Janson, Guilherme; Tompson, Bryan; Alvares, José Carlos de Castro; Valarelli, Fabrício Pinelli; Freitas, Karina Maria Salvatore (February 2021). "Treatment Effects of the Herbst Appliance in Class II Malocclusion Patients after the Growth Peak". European Journal of Dentistry. 15 (1): 039–046. doi:10.1055/s-0040-1715789. ISSN 1305-7456. PMC 7902098. PMID 32869221.
- ^ Barnett, Gregory A.; Higgins, Duncan W.; Major, Paul W.; Flores-Mir, Carlos (2008-03-01). "Immediate Skeletal and Dentoalveolar Effects of the Crown- or Banded Type Herbst Appliance on Class II division 1 Malocclusion". The Angle Orthodontist. 78 (2): 361–369. doi:10.2319/031107-123.1. ISSN 0003-3219. PMID 18251608.
- ^ a b Wei, Robert; Atresh, Arjun; Ruellas, Antonio; Cevidanes, Lucia; Nguyen, Tung; Larson, Brent; Magnum, Jonathan; Manton, David; Schneider, Paul (20 August 2020). "Three-dimensional condylar changes from Herbst appliance and multibracket treatment: A comparison with matched Class II elastics". PubMed. Retrieved 21 February 2024.