The objective of this review is to deepen understanding and emphasize scientific and technological progress in the transformation of crop by-products into bio-based dental materials. Amid heightened environmental sustainability consciousness, various sectors including dentistry have achieved novel advancements by utilizing bio-based materials from crop by-products for dental restorations. This paper provides a thorough review of the extraction, processing, and application of natural polymers, biopolymers, and bio-based mixtures at both the macroscopic and nanoscopic scales, with a focus on their contextualization within dental practices. The performance and efficacy of bio-resins, bio-sourced monomers, and biopolymers derived from these resources were scrutinized and compared with traditional petroleum-based counterparts. This study addresses the recycling and industrial valorization of bio-based dental materials, emphasizing their potential to foster a circular economy in dentistry.