Patent intrudction of Innovative Mandibular Impacted Wisdom Tooth Traction Device from DTC

  Hangzhou DTC Medical Apparatus Co., Ltd. (DTC Orthodontics) has independently developed a "traction device for impacted mandibular wisdom teeth" (Patent No.: CN 223169818 U). This patented apparatus introduces an anchor-supported, screw-driven mechanical uprighting and traction system. By combining multi-tooth rigid anchorage with precision screw-guided propulsion, the device delivers calibrated, directional vector control to upright and guide impacted third molars, offering a dependable clinical solution for complex impaction management and natural tooth preservation.

Resolving Clinical Dilemmas in Impacted Molar Uprighting

  Mandibular third molar impaction represents a frequent and difficult challenge in orthodontic therapy. Constrained by limited retromolar space and mandibular arch crowding, third molars often develop in mesioangular, horizontal, or low-seated orientations. Left unaddressed, these impactions frequently lead to pericoronitis, interproximal caries, anterior arch crowding, or root resorption on adjacent second molars.

  When attempting to upright a viable third molar—either to preserve natural dentition or to substitute for a compromised second molar—clinicians traditionally rely on cantilever uprighting springs, elastomeric chains, or temporary anchorage devices (TADs). However, elastic auxiliaries suffer from rapid force decay and inconsistent vector control, while traditional wire springs can cause soft tissue impingement in the narrow retromolar space. Furthermore, skeletal mini-screw insertion is often limited by anatomical cortical bone density and root proximity. DTC’s R&D team developed this dedicated mechanical traction assembly to overcome these biomechanical inconsistencies, providing continuous, stable, and vector-true uprighting force.

Precision Screw Propulsion: Controlled Displacement and Stable Eruption

  The central mechanism of this patent is a rigid, screw-driven propulsion assembly composed of an integrated support framework, sliding adjusting rods, a threaded mounting block, an adjustment drive bolt, and a terminal abutment thrust plate.

  In clinical application, the framework features a slotted guide aperture that houses the sliding adjusting rods. These parallel rods are bridged by a stabilizing crossbar to establish a torsion-resistant dual-rod architecture. The mounting block houses a precision internal thread through which the adjustment drive bolt passes, with its terminal end bearing securely against the thrust plate on the sliding rod.

  When vector adjustment or reactivation is required, the clinician rotates the bolt using a matching chairside tool. This rotational motion translates directly into a continuous, uniform linear thrust against the thrust plate, smoothly advancing the sliding rod and applying a sustained, directional uprighting force onto the impacted wisdom tooth. Because displacement is mechanically locked and adjustable by fractions of a millimeter, the risk of vector deflection or reciprocal tipping is substantially mitigated. Additionally, integrated limit stoppers on the sliding rods prevent accidental component dislodgement.

Multi-Tooth Rigid Anchorage and Micro-Groove Bonding Stability

  To withstand functional masticatory loads and deliver reciprocal force control, the device incorporates multiple engineering refinements:

• Dual-Tooth Compound Anchorage: The support framework spans and bonds across two adjacent teeth anterior to the wisdom tooth. Distributing reactive forces across multiple anchor units establishes a stable resistance center, effectively counteracting unwanted reciprocal movement of the anchor molars.

• Cross-Hatched Retentive Micro-Grooves: The bonding pads interfacing with the enamel surfaces feature precision-milled, cross-hatched micro-grooves. This geometry substantially increases the microscopic surface area and strengthens mechanical interlocking with orthodontic composite adhesives, ensuring durable bond retention in moist oral environments under continuous loading.

• Biocompatibility and Smooth Contouring: Cast as an integrated unit from high-grade medical stainless steel, all structural margins are radiused and electro-polished. This low-profile geometry minimizes cheek irritation and plaque accumulation, enhancing patient tolerance throughout active uprighting.

  
  

Engineering Synthesis and Clinical Value

  The granting of this utility model patent underscores DTC’s continued dedication to resolving specific clinical bottlenecks through biomechanical innovation. By integrating dual-tooth rigid anchorage, micrometer-calibrated screw propulsion, torsion-resistant dual-rod guidance, and retentive micro-groove bonding into a single device, this patented design establishes an intuitive and predictable biomechanical system for impacted molar uprighting. It reduces chairside manipulation complexity, improves force predictability, and broadens clinical pathways for preserving impacted teeth as functional alternatives to surgical extraction.