Objective: The clinical observation that some patients report intra-operative pain during exodontia despite objective signs of profound local anaesthesia represents a persistent and often misunderstood phenomenon in everyday dental practice. This narrative review examines the physiological, pharmacological, anatomical and psychological bases of this discrepancy, with the aim of clarifying the distinction between a true failure of anaesthesia and a physiological misunderstanding of non-nociceptive sensation as pain. Methodology: A narrative review of the peer-reviewed dental, anaesthesiology and pain science literature was conducted. Sources were identified through targeted searches of biomedical databases and were synthesised under four physiological domains: (1) pharmacological and biochemical determinants of local anaesthetic efficacy in inflamed tissue; (2) anatomical variation and accessory or cross-innervation; (3) the neurophysiology of differential nerve fibre blockade and residual proprioception; and (4) the psychological and central modulation of pain perception, including anxiety, catastrophising and nocebo phenomena. Major Findings: Profound local anaesthesia abolishes conduction in nociceptive Aδ and C fibres but does not, and is not intended to, abolish conduction in the larger, more resistant Aβ fibres that mediate pressure, tension, stretch and proprioception. Consequently, the mechanical forces of elevation, luxation and forceps application during exodontia continue to be transmitted to the central nervous system as pressure and movement. In patients with heightened anxiety, prior traumatic dental experience, pain catastrophising or nocebo expectation, this legitimate non-nociceptive afferent input is frequently misattributed and reported as pain, even when nociceptive transmission is fully blocked. True anaestheticfailure, driven by inflammatory acidosis, tetrodotoxin-resistant sodium channel upregulation, accessory or cross-innervation, and anatomical barriers to diffusion, must be differentiated from this physiological misunderstanding, as the two require fundamentally different clinical responses. Conclusion: The perception of pain during exodontia under profound anaesthesia is frequently a physiological and psychological misunderstanding of preserved proprioceptive and pressure sensation rather than evidence of inadequate nociceptive blockade. Pre operative communication that explicitly distinguishes pressure from pain, together with anxiety-reducing strategies and vigilant clinical differentiation from genuine anaesthetic failure, may reduce patient distress, improve informed consent, and refine clinical decision making during extraction.    

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