This study aimed to evaluate the effect of silver nanoparticles (AgNPs) alone or in combination with calcium hydroxide (Ca(OH)₂) on the proliferation, viability, attachment, migration, and osteogenic differentiation of human mesenchymal stem cells (hMSCs). Different concentrations of AgNPs alone or mixed with Ca(OH)₂ were prepared. Cell proliferation was measured using AlamarBlue, and hMSCs attachment to dentin disks was evaluated using scanning electron microscopy. Live–dead imaging was performed to assess apoptosis. Wound healing ability was determined using the scratch-migration assay. To evaluate osteogenic differentiation, the expression of Runt-related transcription factor (RUNX2), Transforming growth factor beta-1 (TGF-β1), Alkaline Phosphatase (ALP), and Osteocalcin (OCN) were measured using real-time reverse transcriptase polymerase chain reaction. ALP staining and activity were also performed as indicators of osteogenic differentiation. AgNPs alone seemed to favor cell attachment. Lower concentrations of AgNPs enhanced cell proliferation. AgNP groups showed markedly less apoptosis. None of the medicaments had adverse effects on wound closure. The expression of TGF-β1 was significantly upregulated in all groups, and OCN was highly expressed in the AgNP groups. AgNPs 0.06% showed the most enhanced ALP gene expression levels, activity, and marked cytochemical staining. In conclusion, AgNPs positively affect hMSCs, making them a potential biomaterial for various clinical applications.

This study aimed to compare the effect of thickness and background on the color changes of CAD/CAM materials (zirconia-reinforced lithium silicate (Suprinity), lithium disilicate (IPS E-max CAD), and hybrid ceramic (Enamic)). Twelve specimens for each thickness (0.4 mm, 0.5 mm, 1 mm, 1.5 mm, and 2 mm) were obtained by sectioning three CAD/CAM materials. A spectrophotometer was used to measure the color change of the specimens against different backgrounds (A2 enamel, A4 dentin, gray, and metal) using the CIELab color space system. Analysis of variance, sample t-test, and posthoc multiple comparison tests were used to evaluate and compare the color changes for different material types, thicknesses, and background colors, with a significance level of P ≤ 0.05. The result demonstrated that material type, the thickness of the material, and the color of the background had a significant effect on ΔE (P = 0.000). Regardless of the material thickness, Suprinity had the highest mean ΔE values (5.4 ± 1.9), and E-max had the lowest mean ΔE values (1.1 ± 0.6). At 2 mm thickness, Enamic presented the lowest ∆E values (0.5 ± 0.5) against the A2 background. The 0.5 and 1 mm specimens corresponded to the highest ΔE values, whereas the 1.5 and 2 mm thickness specimens predominantly gave the lowest ΔE values. All the independent factors, including the type and thickness of the material, and color of the background, contributed significantly to ΔE of the tested materials (P ≤ 0.05). The study confirms the high masking ability of the lithium disilicate (E-max) material. In clinical situations where the color of the core needs to be masked, it is recommended to use lithium disilicate (E-max).

Objective: To report a rare case of pulp space tissue growth in a mature mandibular molar with severe endo-periodontal involvement after conservative endodontic treatment and to discuss the possible biological explanations, including regeneration and granulation tissue healing. Severe endo-periodontal lesions are challenging, particularly as endodontic regeneration is usually observed in immature teeth, while revascularization in mature teeth, especially in cases of advanced periodontal disease, is rare, as demonstrated in this case. Methods: This study reports a rare case of tissue regeneration versus granulation tissue healing in the pulp space, occurring alongside periodontal healing, in a mature mandibular molar with necrotic pulp and severe periodontal involvement. A 52-year-old patient presented with a mature mandibular molar (tooth #19) exhibiting necrotic pulp with severe endo-periodontal involvement, including grade-3 mobility, tenderness to percussion, a 12 mm probing depth, and extensive periradicular radiolucency. The tooth was diagnosed with necrotic pulp and symptomatic apical periodontitis and was deemed hopeless, with extraction planned. Results: Following patient refusal, endodontic treatment was initiated, including cleaning, shaping, and placement of the intracanal medicament, Ledermix. The patient canceled the extraction due to symptom resolution and disappeared for 12 months. On return, the patient presented with spontaneous pain exacerbated by thermal stimuli, consistent with symptoms of irreversible pulpitis. Clinical examination revealed significant clinical and radiographic improvements, including reduced probing depth (3 mm), no mobility, resolution of apical translucency, radiographic findings suggestive of canal narrowing, and a positive pulp sensibility response. Re-entry elicited profuse bleeding with newly formed vital tissue beneath the medicament. Sodium hypochlorite irrigation failed to achieve hemostasis; inflamed tissue was removed; root canals were cleaned, shaped and obturated; and treatment was completed with placement of a permanent coronal resin composite restoration. A forty-month follow-up showed an asymptomatic tooth with clinical and radiographic healing. Conclusions: This case demonstrates that conservative endodontic management may result in favorable clinical and radiographic outcomes in mature teeth with severe endo-peroidontal involvement, influencing extraction decisions. It provides clinical evidence suggestive of tissue regeneration and periodontal healing in a mature tooth with necrotic pulp and severe periodontal compromise, challenging conventional prognosis. The observed pulp space tissue growth may be suggestive of regeneration; however, alternative explanations, including granulation tissue healing or repair processes, cannot be excluded. Healing by granulation tissue in the pulp space remains possible. Root canal treatment in advanced endo-perio lesions can yield favorable outcomes and may influence extraction decisions. Further clinical and histological studies are needed to clarify underlying mechanisms and optimize treatment strategies.