Elena Oliva-Ferrusola

Background/Objectives: There is a lack of cohesion in integrating current knowledge on the genetic and environmental etiology of dental impaction. The primary aim of this article is to review the current literature to identify candidate genes involved in the pathogenesis of dental impaction. Methods: A scoping review was conducted following PRISMA-ScR guidelines to identify and organize the available body of evidence. Relevant literature was searched in MEDLINE (via PubMed), Scopus, and Web of Science, with the final search conducted on 03 January 2026. Eligibility criteria included case–control, cohort, cross-sectional observational, and case report studies in humans. Selected studies focused on syndromic and non-syndromic variants, inheritance patterns, and genetic analyses. Risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklists and AMSTAR 2. Results: Only 18 studies met the eligibility criteria. Most articles were case reports and retrospective observational studies, revealing a multifaceted genetic landscape underlying dental impaction, with mutations affecting transcription factors and signaling pathways critical for odontogenesis, particularly RUNX2, FGFR1, MSX1, PAX9, and AXIN2. Overall, the included studies showed moderate methodological quality. Conclusions: Current evidence does not clearly support specific genes as causal factors in dental impaction, but instead suggests a complex, likely polygenic susceptibility that modulates the anatomical threshold for tooth eruption. This review highlights RUNX2, FGFR1, MSX1, PAX9, and AXIN2, as well as emerging candidates involved in eruption and bone remodeling pathways. Future progress depends on standardized phenotyping, large replicated cohorts, and functional studies linking genetic variation to dental follicle-mediated eruptive remodeling.

Background: Sealing the peri-implant tissue is a determining factor for long-term implant survival. In the transmucosal region, the cervical fraction of the prosthetic crown is in contact with these tissues, so mucointegration will also be influenced by the biomaterial used for the prosthetic restoration. This study aims to compare the tissue response generated by definitive restorative materials and polymeric materials from a histological point of view. Methods: This study performed an observational prospective cohort study in which biopsies of the peri-implant mucosa were taken after placement of implant-supported prosthetic restorations made of different materials (zirconium oxide, lithium disilicate, and PMMA). Results: A statistically significant difference was observed in the increase in the thickness of the non-keratinized epithelium when comparing the definitive materials (zirconium oxide/lithium disilicate) vs. the provisional material (PMMA) and in the number of collagen fibers when comparing zirconium oxide and lithium disilicate. Conclusions: This study found that zirconia is the material that presents the most adequate biological response of peri-implant tissues. It shows a lower intensity of inflammatory cellular content, a total normality in the number of collagen fibers (the arrangement of the fibers is normal in 90% of the cases), and vascular proliferation of connective tissue in 83% of the cases. These parameters make it a material with a predictable response. Similarly, only the following slight statistically significant differences between the definitive and provisional materials are observed, indicating that the biological response generated by the provisional material (PMMA) is not very different from that obtained with the placement of the definitive restoration.