Background: The phenomenon of pink teeth represents a notable observation in forensic science, although its interpretation remains complex and not directly attributable to a specific cause of death. Methods: This systematic review provides an updated and comprehensive overview of the morphological and histological mechanisms associated with this finding, with a focus on hemoglobin diffusion and pigment accumulation during putrefaction rather than on detailed biochemical pathways. Results: Environmental conditions, especially high humidity and moderate temperatures, are identified as key facilitators. The synthesis of the available evidence, including case reports, observational series, and experimental studies, confirms that pink discoloration is primarily linked to postmortem hemoglobin diffusion following erythrocyte breakdown and release of heme groups into dentinal structures. This process occurs more frequently under conditions that preserve hemoglobin and facilitate its migration into dental tissues. Importantly, pink teeth have been documented across a wide spectrum of postmortem scenarios, such as hanging, drowning, carbon monoxide poisoning, and prolonged exposure to humid environments, indicating that their presence is neither pathognomonic nor exclusively associated with a specific cause of death. Assessment methods include semi-quantitative visual scoring systems (e.g., SPTC and SPTR), spectrophotometric assays, and histochemical analyses for hemoglobin derivatives. Recent advances in digital forensics, particularly micro-computed tomography and artificial intelligence-based segmentation, may further support the objective evaluation of chromatic dental changes. Conclusions: This review underscores the need for standardized approaches to the identification, classification, and analysis, both qualitative and quantitative, of pink teeth in medico-legal practice. Although not diagnostic in isolation, their systematic study enhances our understanding of decomposition processes and contributes supplementary interpretive data in forensic investigations.