Background: The objective of this study was to use CBCT to look into the root canal morphology of maxillary premolars in a Saudi Arabian subpopulation and associate the results to existing canal morphology classifications. Methods: The sample size for this analysis was 500 right and left untreated maxillary first and second premolars with fully formed roots from 250 Saudi residents (125 male and 125 female). The following observations were made using CBCT on the teeth related: (1) The number and morphology of roots; (2) The canal morphology for each root according to Vertucci's classification. The frequency and similarities between the right and left sides, as well as between females and males, were studied. The Chi-square test was used to assess the results. Results: Of the 500 maxillary first premolars studied, 199 teeth had one root (39.8%), whilst 293 (58.6%) were two-rooted. Three-rooted maxillary first premolars were found in 8 (1.6%). For maxillary second premolars, 416 premolars had one root (83.2%), whilst 79 (15.8%) had two roots and the rest 5 (1.0%) were three roots. There were significant differences of number of root were found between groups (p > 0.05). For maxillary first premolar, Type IV was the most frequent, accounting for 57.8% of the sample (n = 289), followed by type II (32.8%, n = 164). For maxillary second premolar, Type I was mainly occurrence 302 (60.4%), followed by Type II (16.4%, n = 82). Conclusions: The majority of maxillary first premolars had two roots and two root canals, while one root and one root canal was the most common anatomical configuration for maxillary second premolars. Additional canal forms do occur on occasion, and clinicians should pay close attention to them.

Objectives. The efficacy of root canal therapy is dependent on a thorough understanding of both normal and aberrant root canal morphology. As a result, the purpose of this study was to use CBCT to characterize the exact root and canal morphology of mandibular premolars in a Saudi subpopulation. Methods. The current study included 1000 mandibular premolars (507 first premolars and 493 second premolars) with completely developed roots. CBCT was performed to assess the shape of the roots and to classify the canal anatomy according to Vertucci’s classification. The incidence and similarity of the left and right sides, as well as men and women, were investigated. The data were examined using the chi‐square test. Results. Of the 507 mandibular first premolars analyzed, 484 (95.5%) had one root, whereas 23 (4.5%) had two roots. Of the 493 mandibular second premolars analyzed, 489 (99.2%) had one root, whereas four teeth had two roots (0.8%). There were no statistically significant variations in the number of roots identified across groups (p > 0.05). The most prevalent in mandibular first premolars was type I, accounting for 70.0% (n = 355) of the studied sample, followed by type II (14.2%, n = 72) and type IV (10.1%, n = 51). For mandibular second premolar, type I had the highest incidence (449 (91.1%)), followed by type II (5.7%, n = 28). Conclusion. In a Saudi subpopulation, the majority of mandibular first and second premolar teeth had a single root with a type I canal system. On the other hand, numerous roots with various canal classifications were found.

Knowledge of Primary School Teachers Regarding Dental Trauma Management in Hail Region, Saudi Arabia

Metformin is a promising small molecule for dentin regeneration, but an effective local delivery system for pulp applications has been underexplored. This study encapsulated metformin in poly(lactic-co-glycolic acid) (PLGA) microspheres and incorporated them into calcium phosphate–chitosan cement (CPCC) as a direct pulp-capping material (DPC). Metformin-PLGA microspheres were prepared by double emulsion and mixed with CPCC at a concentration of 0% to 20% by weight. Microsphere morphology, encapsulation efficiency, chemical composition, and physico-mechanical properties were characterized, and compatibility with human dental pulp stem cells (hDPSCs) was evaluated by live/dead assay and SEM. The microspheres were spherical (5.43 ± 0.17 µm) with (51 ± 3.69%) encapsulation efficiency, and FTIR confirmed metformin incorporation. The 15% Met-PLGA-CPCC group showed flexural strength (15.22 ± 1.98 MPa), elastic modulus (4.60 ± 0.73 GPa), and work of fracture (104.96 ± 12.48 J/m²) comparable to or higher than CPCC and MTA, while all Met-PLGA-CPCC groups had shorter setting times ranging from 18 min to 27 min than CPCC (39.15 ± 2.10 min) and MTA (123 ± 4.2 min). Metformin release increased proportionally with Met-PLGA content. hDPSCs exhibited good attachment and high viability on all materials over the evaluated period. In conclusion, Met-PLGA-CPCC provides fast-setting and favorable physico-mechanical properties, sustained metformin delivery, and excellent hDPSC compatibility. These properties support its potential as a bioactive direct pulp-capping material and as a versatile platform for regenerative applications.

Secondary caries and biofilm accumulation remain major causes of failure in provisional crowns and restorations, highlighting the need for multifunctional resin coatings with antibacterial and remineralizing capabilities. This study aimed to develop a novel bioactive and antibacterial resin-based surface coating incorporating 10% dimethylaminododecyl methacrylate (DMADDM), 20% nanoparticles of amorphous calcium phosphate (NACP), and/or 20% calcium fluoride nanoparticles (nCaF₂) within a urethane dimethacrylate/triethylene glycol divinylbenzyl ether (UDMA/TEG-DVBE) matrix. Coatings were evaluated for degree of conversion (DC), flow, shear bond strength, brushing wear resistance (10,000 cycles), and calcium (Ca), phosphate (PO₄), and fluoride (F) ion release up to 70 days. All groups achieved clinically acceptable polymerization, with the lowest DC at 50%. NACP-containing coatings significantly increased shear bond strength to 18.3 ± 2.8 MPa, representing a ~170% increase compared with the experimental control (6.8 ± 2.1 MPa) and exceeding the ISO 10477 minimum threshold of 5 MPa. After brushing simulation, experimental coatings demonstrated low wear depth (0.93–1.19 µm), which was ~40% lower than the commercial control (1.85 ± 0.40 µm). Sustained ion release was achieved for 70 days, with 20% NACP-formula releasing 1.22 mmol/L Ca and 0.90 mmol/L PO₄, while the dual NACP–nCaF₂ formulation provided simultaneous Ca (0.62 mmol/L) and F (0.33 mmol/L) release. The developed coatings demonstrated promising physicochemical properties, bonding performance, wear resistance, and sustained remineralizing ion release, supporting their potential application as therapeutic surface coatings for provisional restorations.

Background: Tooth root caries and periodontal tissue loss remain major challenges in elderly and periodontally compromised patients, while current restorative materials lack combined antibacterial and regenerative properties. Objective: The objective of this study was to develop a novel metformin-containing antibacterial composite for root cavity restorations to prevent recurrent caries and potentially promote periodontal tissue regeneration. Methods: Experimental composites contained 5% dimethylaminohexadecyl methacrylate (DMAHDM), varying metformin concentrations (2.5–15%), and glass fillers. Mechanical and antibacterial properties as well as cytocompatibility toward human periodontal ligament stem cells (hPDLSCs) were investigated. Results: The experimental composites achieved flexural strengths of 67.9 to 50.1 MPa (n = 6), significantly higher than (41.3 ± 3.4 MPa) of commercial control Vitremer (p < 0.05), while maintaining clinically acceptable elastic moduli of 3.7–3.1 GPa. Experimental composites achieved an 8-log reduction in Streptococcus mutans (S. mutans) biofilms and significantly reduced lactic acid production and metabolic activity compared to biofilms on commercial controls. The composite containing 15% metformin demonstrated acceptable cytocompatibility toward hPDLSCs under clinically relevant diluted conditions, matching commercial controls (p > 0.1). Conclusions: These findings suggest that this novel composite possesses potent antibacterial activity, acceptable cytocompatibility, and adequate mechanical properties, making it promising for multifunctional root caries restorations.