Stainless steel crowns (SSCs) have long been a durable, cost-effective, and reliable treatment option for primary and select permanent teeth. Despite their clinical advantages, concerns remain regarding esthetics, technique sensitivity, and, most importantly, the release of nickel ions into the oral environment. Nickel, a key component of stainless steel alloys, is a well-documented allergen and has been associated with contact dermatitis, immunological changes, and systemic effects, particularly in children. Nickel ion release from SSCs may be influenced by oral pH, abrasion, and duration of exposure, raising biocompatibility concerns. This review highlights the benefits and limitations of SSCs, with particular emphasis on nickel hypersensitivity, its underlying immunologic mechanisms, and the need for safer, biologically compatible alternatives in pediatric dentistry.
