Introduction
The learning curve and manual dexterity development for endodontic procedures can be challenging and time-consuming because root canal therapy is accomplished through several steps. Due to this, new teaching techniques have been incorporated into the training of human dentistry practitioners in the last decade.1–3. Training of veterinary dentistry practitioners is comparable to that for humans. 7,9. Due to the importance of introducing teaching alternatives for enhancing the pre-clinical skills of veterinarians, this study aimed to assess the feasibility of creating 3D-printed teeth from an adult dog skull and to validate their use as an alternative training method for root canal therapy in this species.

Materials and Methods
3D-printed tooth design: one cadaver head from a mesaticephalic mature 15 kg adult mixed breed with fully developed dentition was selected, macerated, the dentition was carefully removed from the jaws and scanned with a 3D cone beam computed tomography (CBCT) unit to obtain appropriate high-definition 3D images. Three-dimensional images and resin 3D-printed models of sixteen teeth selected from the entire dentition as the most representative for endodontic training needs were reproduced: 101–104, 108, 201–204, 206, 208, 304, 306, 309, 404, 409.

Pre-clinical Validation of the 3D-printed Teeth: after the initial survey validation, 40 veterinary dental specialists from Brazil were selected to participate in the study using a non-probabilistic intentional sampling method. All of them received a link to answer a 24-question survey in Google Forms and a 3D-print mandibular first molar tooth with same anatomical conformation and pulp cavity diameter to perform a complete root canal therapy. The respondent’s level of agreement or disagreement with the questions proposed in this study was evaluated through a 5-point Likert scale: 1 = strongly disagree; 2 = partially dis- agree; 3=indifferent; 4=partially agree; 5: strongly agree. 

Results and conclusions
It is feasible to create 3D-printed models of dog teeth with high accuracy for the endodontic system. Despite the differences in the properties between natural and artificial teeth, it is possible to use artificial teeth as training devices for conventional endodontic treatment in dogs. The reliability level for the survey was reported as good, displaying a coefficient above 0.86. The resin used to create the enamel and dentin displayed good radiographic contrast, allowing the authors to distinguish between the radiolucent area of the artificial pulp cavity and the radiopaque endodontic material used during the obturation and restoration phases. Animal mannequins generally allow students to develop their techniques reducing the risk of harm to the patient or themselves, provide a safe and controlled environment for students to practice procedures and it can be customized to simulate different conditions18. This can help students better understand and prepare for the challenging situations they may face in their future practices.

References
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