In orthodontic treatment, tooth movement is not merely a matter of repositioning the dental crown; rather, it is a complex biological process involving the supporting structures of the teeth, including the periodontal ligament (PDL), alveolar bone, and the surrounding vascular system. Principles of orthodontic biomechanics form the foundation for designing forces that are safe, effective, and predictable, allowing teeth to move to their intended positions without damaging the supporting tissues. Recent research conducted by a student of the Faculty of Dentistry, Universitas Gadjah Mada, Tegar Arviga, under the supervision of Dr. drg. Cendrawasih Andusyana Farmasyanti, M.Kes., Sp.Ort(K), and drg. Yanuarti Retnaningrum, Sp.Ort(K), demonstrated that biological interventions—such as injections of tissue-derived materials (e.g., platelet-rich fibrin)—may influence biological mediators, including osteoprotegerin, during orthodontic tooth movement.
This article reviews the concept of tooth movement biomechanics in modern orthodontics, covering types of movement, tissue mechanisms, and their clinical implications.
Concepts of Tooth Movement Biomechanics
Orthodontic Forces and Tissue Response
Orthodontic biomechanics explains that when force is applied to a tooth, two primary zones are formed within the periodontal ligament and alveolar bone: a pressure (compression) zone and a tension zone. In the pressure zone, bone resorption occurs, while in the tension zone, bone deposition takes place—allowing tooth movement to occur in harmony with bone remodelling.
Types of Tooth Movement
Several types of tooth movement are commonly employed in orthodontic practice, including tipping, translation (bodily movement), rotation, intrusion, and extrusion. Each movement requires different force control. For example, tipping requires relatively light forces applied over time to move the crown, whereas translation requires greater moments to ensure that the root moves together with the crown.
Biological Factors and Interventions
The biological response to orthodontic force depends on the condition of the periodontal ligament, alveolar bone quality, patient age, and the rate of tissue remodelling. Experimental studies indicate that injections of materials such as platelet-rich fibrin can modulate biological mediators, including osteoprotegerin, which plays a key role in bone remodelling during orthodontic tooth movement.
Biomechanics in Modern Orthodontic Practice
Optimal Force Design
To achieve favourable orthodontic outcomes, applied forces must be light enough to avoid periodontal ligament necrosis and excessive hyalinisation, yet sufficient to trigger cellular responses. The concept of optimal force is therefore essential in the mechanical design of orthodontic treatment.
Monitoring and Adaptation
In modern practice, digital technologies—such as 3D cephalometry and intraoral scanning—enable orthodontists to monitor tooth movement with high precision and adjust applied forces according to individual patient responses. As such, biomechanics functions not merely as a theoretical framework, but as a dynamic clinical tool.
Clinical Implications of Biological Interventions
Research integrating biomechanics with biological interventions (e.g., platelet-rich fibrin injections) signals a new era in orthodontics—one that extends beyond the application of mechanical forces to actively supporting tissue responses through biological modulation. This approach has the potential to accelerate tooth movement while reducing adverse tissue effects.
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Biomechanics of tooth movement in orthodontics involves a combination of controlled mechanical force application and biological responses of the supporting tissues. A comprehensive understanding of movement types, bone remodelling principles, and biological intervention methods allows orthodontists to design treatment plans that are more efficient, safe, and predictable. Supported by advances in technology and contemporary research, orthodontic practice continues to progress toward optimal patient outcomes.
References
Tegar Arviga, Dr. drg. Cendrawasih Andusyana Farmasyanti, M.Kes., Sp.Ort(K) , drg. Yanuarti Retnaningrum, Sp.Ort(K), “PENGARUH INJEKSI PLATELET-RICH FIBRIN DAN ADVANCED-PLATELET-RICH FIBRIN TERHADAP KADAR OSTEOPROTEGERIN SELAMA PERGERAKAN GIGI ORTODONTI (Studi Eksperimental pada Kelinci Oryctolagus cuniculus)”, Universitas Gadjah Mada. https://etd.repository.ugm.ac.id/home/detail_pencarian_downloadfiles/1423529
Author: Rizky B. Hendrawan | Photo: Freepik
