Conventional orthograde root canal therapy — complete pulp extirpation, straight line coronal access, full biomechanical shaping to the apical constriction, and three dimensional obturation — remains the reference standard in endodontics, with long term radiographic and clinical success rates generally exceeding 85%. However, a growing body of comparative and cohort literature indicates that deliberate departures from this conventional protocol — minimally invasive access cavity design, vital pulp therapy and pulpotomy in mature teeth, regenerative endodontic procedures in immature necrotic teeth, bioceramic single-cone obturation, intentional replantation, and simplified single-visit protocols — can achieve equivalent, and in selected scenarios superior, radiographic healing. This narrative review synthesises evidence from systematic reviews, randomised controlled trials, and cohort studies published between 2010 and 2026 comparing conventional and unconventional endodontic strategies across six domains. The reviewed literature suggests that unconventional approaches frequently succeed because they preserve pericervical and radicular dentin, thereby reducing the biomechanical burden that predisposes conventionally treated teeth to fracture and extraction; because they exploit the bioactivity of hydraulic calcium silicate materials that form an apatite interface and stimulate hard-tissue deposition; because they permit continued root maturation that thickens dentinal walls in immature teeth; and because they minimise specific iatrogenic risks, such as coronal microleakage, associated with prolonged, multi appointment protocols. Radiographically, these mechanisms manifest as re formation of the lamina dura, normalisation of periodontal ligament space, resolution of periapical radiolucency, and measurable increases in root length, wall thickness, and root area. The evidence is heterogeneous and strongly case-selection dependent — at least one randomised trial found conventional canal preparation to outperform a minimally invasive protocol on strict periapical healing criteria — but overall supports considering unconventional endodontic strategies as legitimate, evidence-based options rather than treatments of last resort.

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