Autonomous robotic execution of nonlinear toolpaths for geometry-matched osteotomy in tooth autotransplantation: an in vitro study

Abstract

Tooth autotransplantation requires recipient socket preparation that matches donor root morphology while preserving surrounding bone. We developed an autonomous multi-axis robotic system that executes nonlinear, surface-conforming milling trajectories to create a geometry-matched socket and compared it with a static tooth-supported guide in forty 3D-printed mandibular models representing single-rooted and double-rooted anatomies. Recipient sockets were planned by offsetting the donor root surface by 0.5 mm and eliminating insertion axis undercuts. The robot executed the planned milling path with a depth-stop Lindemann bur, whereas the guide workflow used guided pilot drilling followed by freehand refinement. Robot assistance reduced deep positional errors and improved agreement between planned and prepared socket geometry, with the most pronounced benefit in double-rooted models, while overall preparation time was comparable between approaches. These findings support further clinical validation to confirm that autonomous robotic, surface-conforming osteotomy can improve full-depth geometric fidelity and reduce unnecessary bone removal in technique-sensitive autotransplantation procedures.

References

[1] Plotino G, Abella Sans F, Duggal MS, et al. . European Society of Endodontology position statement: surgical extrusion, intentional replantation and tooth autotransplantation: European Society of Endodontology developed by. Int. Endod. J., 2021, 54: 655-659

[2] Plotino G, Abella Sans F, Duggal MS, et al. . Present status and future directions: surgical extrusion, intentional replantation and tooth autotransplantation. Int. Endod. J., 2022, 55: 827-842

[3] Plakwicz P, Orzechowska S, Czochrowska EM. Regeneration of the alveolar bone after autotransplantation of teeth in children. Semin. Orthod., 2023, 29: 164-170

[4] Czochrowska, E. & Plakwicz, P. Alveolar bone regeneration after transplantation of immature teeth in orthodontic patients. Periodontol. 2000https://doi.org/10.1111/prd.70023 (2025).

[5] Chung W, Tu Y, Lin Y, Lu H. Outcomes of autotransplanted teeth with complete root formation: a systematic review and meta-analysis. J. Clin. Periodontol., 2014, 41: 412-423

[6] Lucas-Taulé E, Llaquet M, Muñoz-Peñalver J, Nart J, Hernández-Alfaro F, Gargallo-Albiol J. Mid-term outcomes and periodontal prognostic factors of autotransplanted third molars: a retrospective cohort study. J. Periodontol., 2021, 92: 1776-1787

[7] Huang J, Gan Y, Han S, et al. . Outcomes of autotransplanted third molars with complete root formation: a systemic review and meta-analysis. J. Evid. Based Dent. Pract., 2023, 23 101842

[8] Tsukiboshi M, Tsukiboshi C, Levin L. A step-by step guide for autotransplantation of teeth. Dent. Traumatol., 2023, 39: 70-80

[9] Raabe C, Bornstein MM, Ducommun J, Sendi P, Von Arx T, Janner SFM. A retrospective analysis of autotransplanted teeth including an evaluation of a novel surgical technique. Clin. Oral. Investig., 2021, 25: 3513-3525

[10] Zhang J, Han Y, Zhong H. Accuracy assessment between computer-guided surgery planning and actual tooth position during tooth autotransplantation. Dent. Traumatol., 2024, 40: 649-657

[11] Verweij JP, Van Westerveld KJH, Anssari Moin D, Mensink G, Van Merkesteyn JPR. Autotransplantation with a 3-dimensionally printed replica of the donor tooth minimizes extra-alveolar time and intraoperative fitting attempts: a multicenter prospective study of 100 transplanted teeth. J. Oral. Maxillofac. Surg., 2020, 78: 35-43

[12] Hou R, Yun J, Hui X, et al. . The design, fabrication, and clinical application of a universal donor tooth model in autotransplantation. J. Dent., 2025, 162 106059

[13] EzEldeen M, Wyatt J, Al-Rimawi A, et al. . Use of CBCT guidance for tooth autotransplantation in children. J. Dent. Res., 2019, 98: 406-413

[14] Li Y, Lin Z, Liu Y, et al. . Fully guided system for position-predictable autotransplantation of teeth: a randomized clinical trial. Int. Endod. J., 2025, 58: 550-565

[15] Lucas-Taulé E, Llaquet M, Muñoz-Peñalver J, Somoza J, Satorres-Nieto M, Hernández-Alfaro F. Fully guided tooth autotransplantation using a multidrilling axis surgical stent: proof of concept. J. Endod., 2020, 46: 1515-1521

[16] Alqutaibi AY, Hamadallah HH, Abu Zaid B, Aloufi AM, Tarawah RA. Applications of robots in implant dentistry: a scoping review. J. Prosthet. Dent., 2025, 134: 1052-1061

[17] Liu C, Li Y, Wang F, Liu Y, Bai S, Zhao Y. Development and validation of a robotic system for milling individualized jawbone cavities in oral and maxillofacial surgery. J. Dent., 2024, 150 105380

[18] Liu C, Liu Y, Xie R, Li Z, Bai S, Zhao Y. The evolution of robotics: research and application progress of dental implant robotic systems. Int. J. Oral. Sci., 2024, 16: 28

[19] Yang T, Xing X, Xu W, Wu B. Accuracy of robotic-assisted implant placement in second molars combined with step drills and manual-automatic switching function: a retrospective study. BMC Oral. Health, 2025, 25 1844

[20] Zhao W, Teng W, Su Y, Zhou L. Accuracy of dental implant surgery with freehand, static computer-aided, dynamic computer-aided, and robotic computer-aided implant systems: an in vitro study. J. Prosthet. Dent., 2025, 134: 2416-2423

[21] Liu C, Wang X, Liu Y, et al. . Comparing the accuracy and treatment time of a robotic and dynamic navigation system in osteotomy and root-end resection: an in vitro study. Int. Endod. J., 2025, 58: 529-540

[22] Liu C, Liu X, Wang X, et al. . Endodontic microsurgery with an autonomous robotic system: a clinical report. J. Endod., 2024, 50: 859-864

[23] Liu Y, Liu C, Bai S, Zhao Y. Accuracy of robot-guided access cavity preparation in managing calcified canals: an in vitro study. Int. Endod. J., 2026, 59: 262-270

[24] Yu P, Luo H, Zhang X, Zhao R, Patel S. Robotic navigation system for management of pulp canal obliteration: a case report. Int. Endod. J., 2025, 58: 1659-1665

[25] Ma Z, Guo Z, Ding Z, et al. . Evaluation of a newly developed oral and maxillofacial surgical robotic platform (KD-SR-01) in head and neck surgery: a preclinical trial in porcine models. Int. J. Oral. Sci., 2024, 16: 51

[26] Li Y, Zhou Y, Lyu J, Cao X, Tan J, Liu X. Feasibility and accuracy of semi-active robot-assisted porcelain veneer tooth preparation: an in vitro study. J. Dent., 2025, 162 106012

[27] Li Y, Lyu J, Cao X, et al. . Development and accuracy assessment of a crown lengthening surgery robot for use in the esthetic zone: an in vitro study. J. Prosthet. Dent., 2025, 134: 1936-1943

[28] Liu C, Di T, Chen Y, Wu Lan, Bai S, Zhao Y. Efficiency for robotic-assisted extraction of completely impacted supernumerary teeth in children: a randomized controlled trial. BMC Oral. Health, 2025, 25 1831

[29] Chen G, Ma Z, Luo Z, et al. . Feasibility and precision of robot-assisted autotransplantation of teeth: an in vitro study. Int. Endod. J., 2026, 59: 632-642

[30] Liu Y, Song J, Chen X, et al. . Robot-assisted autotransplantation of third molars in the maxilla: two case reports. Front. Oral. Health, 2025, 6 1661873

[31] Anssari Moin D, Verweij JP, Waars H, Van Merkesteyn R, Wismeijer D. Accuracy of computer-assisted template-guided autotransplantation of teeth with custom three-dimensional designed/printed surgical tooling: a cadaveric study. J. Oral. Maxillofac. Surg., 2017, 75: 925.e1-925.e7

[32] Tsukiboshi M. Autotransplantation of teeth: requirements for predictable success. Dent. Traumatol., 2002, 18: 157-180

[33] Hou R, Hui X, Xu G, et al. . Use of 3D printing models for donor tooth extraction in autotransplantation cases. BMC Oral. Health, 2024, 24 179

[34] Strbac GD, Schnappauf A, Giannis K, Bertl MH, Moritz A, Ulm C. Guided autotransplantation of teeth: a novel method using virtually planned 3-dimensional templates. J. Endod., 2016, 42: 1844-1850

[35] Shi JY, Wu XY, Lv XL, et al. . Comparison of implant precision with robots, navigation, or static guides. J. Dent. Res, 2025, 104: 37-44

[36] Miadili M, Zhang W, Zhang Y, et al. . Robot-assisted extraction of impacted mandibular tooth: a clinical report. BMC Oral. Health, 2025, 25 710

[37] Gómez Meda R, Abella Sans F, Esquivel J, Zufía J. Impacted maxillary canine with curved apex: three-dimensional guided protocol for autotransplantation. J. Endod., 2022, 48: 379-387

[38] Pedrinaci I, Calatrava J, Couso-Queiruga E, et al. . Tooth autotransplantation with adjunctive application of enamel matrix derivatives using a digital workflow: a prospective case series. J. Dent., 2024, 148 105131

[39] Chen D, Chen J, Wu X, Chen Z, Liu Q. Prediction of primary stability via the force feedback of an autonomous dental implant robot. J. Prosthet. Dent., 2024, 132: 1299-1308

[40] Kanmaz MG, Agani Sabah G, Balcı M, Erden MB. Comparison of intraoral scanner accuracy before and after calibration: an in vitro study. BMC Oral. Health, 2025, 25 1186

[41] Yang M, Li R, Li X, Liu S, Li S. Manufacturing and application precision changes in three-dimensional printed surgical guides for dental implants: an in vitro study. Clin. Oral. Implants Res., 2025, 36: 771-784

Funding

National Natural Science Foundation of China (National Science Foundation of China)(82501241)

RIGHTS & PERMISSIONS

The Author(s)