Plaster models with gingival preservation: bibliographic review of analog and digital techniques

Abstract

Preserving gingival architecture allows for better information when fabricating dental restorations; this technique, known as Geller dies, alveolar models, or carrot dies, can be produced both analogically and digitally. The objective of this study was to compare, through a systematic literature review, plaster models with gingival structure preservation obtained through analog versus digital techniques in restorative dentistry. A literature review was conducted in PubMed, Google Scholar, Semantic Scholar, DOAJ, Cochrane Library, Scielo, Redalyc, Dialnet, ResearchGate, Elsevier, and ScienceDirect, using keywords such as "Geller dies", "alveolar model", and "master cast with accurate soft tissue reproduction". A total of 32 articles were identified; 13 were excluded for not meeting the pre-established criteria, leaving 19 for analysis, of which 2 had a digital focus, 5 described the fabrication technique, and 12 applied the technique in clinical cases. Various authors highlight the versatility of these techniques, particularly in implantology and fixed prosthodontics. It cannot be said that one technique is superior to the other; both adequately reproduce gingival architecture, and the choice depends on the operational capabilities, skills, and knowledge of the clinician and dental technician. It is concluded that both analog and digital techniques are valid, each with its advantages and challenges, and combining both could optimize clinical outcomes.