The aim of this study was to compare the interproximal contact tightness of lateral teeth after restoring adjacent proximal walls with four types of direct adherent biomaterials. Distal and mesial boxes were prepared on 160 artificial right first and second upper molars. Each set of 40 pairs of boxes was restored using one bulk biomaterial: Equia Forte Fil HT (GC), Cention^® Forte (IVOCLAR VIVADENT), Admira Fusion x-tra (VOCO), or 3M^TMFiltek^TM One Bulk Fill. The mean difference in the passing-through force varied from sound to restored surfaces immediately after application, as well as at 7 and 14 days after: Equia Forte Fil HT—4.07 ± 0.01, 4.08 ± 0.01, and 4.11 ± 0.01; Cention^® Forte—3.30 ± 0.01, 3.50 ± 0.01, and 3.56 ± 0.01; Admira Fusion x-tra—4.10 ± 0.01, 4.13 ± 0.01, and 4.13 ± 0.01; 3M^TMFiltek^TM One Bulk Fill—4.08 ± 0.01, 4.09 ± 0.01, and 4.07 ± 0.01 (p < 0.05). The passing-through force of the restored contact areas showed significantly higher values when compared to those for the sound surfaces, and among them, all biomaterials presented similar values, except for Cention^® Forte. The potential clinical relevance of this study relates to better knowing the most appropriate restorative material for large proximal caries on adjacent surfaces from the outset of the treatment protocol.

Background: Distal surface caries (DSC) has been associated with partially erupted impacted third molars. The purpose of this study was to compare the rates of DSC between populations that had undergone different third molar management strategies. Methods: Radiographs that had been taken during routine examinations of 1012, 251 and 250 patients in Manchester, Bucharest and Amsterdam, respectively, were evaluated. The following parameters were assessed: the state of the distal surface in the second mandibular molar, loss of periodontal support, impaction type of the third molar, contact point localization, and patients’ genders, ages and their cumulative history of dental health. Results: The rate of DSC in the second mandibular molar was 63.9%, 19.9% and 26.0% in the Manchester, Bucharest and Amsterdam populations, respectively. A loss of lamina dura of ≥2 mm, increased percentages of decayed, missing or filled teeth and male gender were risk factors in all three populations. All assessed parameters apart from the site of the mandible reached statistical significance in the Manchester sample (p < 0.001). The DSC rate was cumulative with increasing age in the Manchester population, in which third molars were strategically retained. Conclusions: The UK population, treated according to strict guidelines that limit the removal of third molars, had a statistically significant higher DSC prevalence rate (p < 0.001) than the Romanian or Dutch populations. The active surgical management of mandibular third molars seems to have the potential to reduce the DSC rate in the adjacent second molar.

Background/Objectives: This scoping review mapped clinical, in vitro, and in silico evidence on non-metal primary crowns in telescopic and double-crown systems involving natural teeth, including retention, wear, mechanical behavior, clinical outcomes, and auxiliary retention-control elements. Methods: PubMed/MEDLINE, Scopus, Dentistry & Oral Sciences Source through EBSCO, and Web of Science were searched for English-language reports published from 2015 onward. These limits and the exclusion of case reports were predefined in a written, unregistered protocol. Elicit provided supplementary citation discovery, and a targeted backward reference-list check was performed using the same eligibility criteria. Findings and extractable numerical retention outcomes were charted descriptively without formal critical appraisal or quantitative pooling. Results: Forty-eight reports were included, 40 in vitro, one in silico, and seven clinical reports, representing six identifiable cohorts. Two clinical reports arose from the same randomized cohort. The backward reference-list check identified nine additional eligible reports. Clinical evidence was concentrated on zirconia primary crowns with electroformed or electroplated gold secondaries, although two additional short-term trials evaluated zirconia with polymeric secondary structures. Retention varied with the complete material and design combination. Four laboratory reports examined auxiliary retention-control concepts; no clinical study isolated their effects. Conclusions: Clinical evidence remains very limited. Polymeric primary crowns and auxiliary retention-control elements were represented mainly by laboratory evidence. Retention should be interpreted as a system-level outcome. Mixed-support outcomes require support-specific interpretation, and this review does not establish comparative clinical superiority.