Next Generation Workflow for Apical Control in Endodontics: three case report

Aim: The aim of this report is to propose a new step-by-step workflow to safely control the apical extent of root canal preparation with the aid of a step-forward motor-driven endodontic technology, specifically the improved Optimum Apical Stop (OAS2) function, to simplify and accelerate traditional root canal procedures.

Summary:
This case series reports on three patients undergoing endodontic therapy using a motor-driven protocol with the Morita Tri Auto ZX2+ device (J. Morita Corp., Osaka, Japan) and its OAS2 function activated. Root canal shaping was initiated with VDW.ROTATE instruments (VDW GmbH, Munich, Germany), followed by refinement using ProTaper Ultimate F2 and F3 files (Dentsply Sirona, Charlotte, NC, USA), and obturation with corresponding gutta-percha cones. Postoperative assessments included clinical evaluation, periapical radiographs, and patient-reported outcomes at 1, 3, 6, and 12 months. Outcome measures included pain, swelling, tooth function, need for reintervention, adverse effects, and radiographic signs of periapical healing.

Immediate postoperative radiographs showed high-quality apical preparation and obturation. At one-year follow-up, all three cases demonstrated complete symptom resolution and radiographic absence of periapical radiolucency.

Key learning points:

• The OAS2 function allows controlled, minimal, and reproducible apical preparation.
• The workflow reduces chair-time and technical variability.
• Outcomes were successful regardless of operator experience.
• Radiographic healing and patient satisfaction were consistently achieved.
• The combined use of VDW.ROTATE and ProTaper Ultimate files supported effective and conservative canal shaping.