This study aimed to identify the role of crosslinking agents in the resin–dentin bond strength (BS) when used as modifiers in adhesives or pretreatments to the dentin surface through a systematic review and meta-analysis. This paper was conducted according to the directions of the PRISMA 2020 statement. The research question of this review was: “Would the use of crosslinkers agents improve the BS of resin-based materials to dentin?” The literature search was conducted in the following databases: Embase, PubMed, Scielo, Scopus, and Web of Science. Manuscripts that reported the effect on the BS after the use of crosslinking agents were included. The meta-analyses were performed using Review Manager v5.4.1. The comparisons were performed by comparing the standardized mean difference between the BS values obtained using the crosslinker agent or the control group. The subgroup comparisons were performed based on the adhesive strategy used (total-etch or self-etch). The immediate and long-term data were analyzed separately. A total of 50 articles were included in the qualitative analysis, while 45 articles were considered for the quantitative analysis. The meta-analysis suggested that pretreatment with epigallocatechin-3-gallate (EGCG), carbodiimide, ethylenediaminetetraacetic acid (EDTA), glutaraldehyde, and riboflavin crosslinking agents improved the long-term BS of resin composites to dentin (p ≤ 0.02). On the other hand, the use of proanthocyanidins as a pretreatment improved both the immediate and long-term BS values (p ≤ 0.02). When incorporated within the adhesive formulation, only glutaraldehyde, riboflavin, and EGCG improved the long-term BS to dentin. It could be concluded that the application of different crosslinking agents such as carbodiimide, EDTA, glutaraldehyde, riboflavin, and EGCG improved the long-term BS of adhesive systems to dentin. This effect was observed when these crosslinkers were used as a separate step and when incorporated within the formulation of the adhesive system.

Introduction. The mental foramen (MF) is a bilateral opening localized on an anterior surface of the mandible. A precise location as well as well-defined shape, size, and number of the MF is crucial for different clinical dental procedures. The aim of this study was to determine a size and location of the MF in relation to the lower teeth using the cone-beam computed tomography (CBCT) study. Material and Methods. In a group of 201 patients (106 males and 95 females) the CBCT images were performed using the GX CB-500 device (Gendex, USA). Results. No significant differences in values of the horizontal (H) and vertical (V) diameters as well as the H:V ratio on both sides in relation to the age of participants were found. In males both average values of a horizontal diameter (p=0.031) and vertical diameter (p=0.001) were significantly higher on the right side than in the female subgroup, whereas on the left side only an average value of a vertical diameter was significantly higher in men (p=0.006) in comparison to women. Moreover, the H:V ratio was significantly lower in males on the left side (p=0.032). There were no significant relationships between age and gender of the patients (p>0.05) and the type of mental foramen on the right and left sides. Conclusions. The application of the CBCT study enabled a precise determination of the shape, size, and position of the mental foramen in relation to the neighboring anatomical structures on a representative group of the Polish patients. The results obtained may contribute to guidelines for dental procedures including anesthesia of the mental nerve and endodontic, implantology, and dental surgery with regard to the location of mental foramen depending on the sex and age of patients.

The main goal of root canal treatment (RCT) is to eradicate or essentially diminish the microbial population within the root canal system and to prevent reinfection by a proper chemo-mechanical preparation and hermetic final obturation of the root canal space. The aim of this study was to assess the quality of the root canal filling and the number of visits needed for completing RCT by operators with different experience, including dentistry students (4th and 5th year), general dental practitioners (GDPs), and endodontists. Data from medical records of 798 patients were analyzed, obtaining 900 teeth and 1773 obturated canals according to the inclusion and exclusion criteria. A similar number of teeth was assessed in each group in terms of density and length of root canal filling and number of visits. The larger number of visits and the lower quality of treatment was observed for 4th year students than for other groups (p < 0.05); in contrast, the endodontists needed the lowest number of visits to complete RCT and more often overfilled teeth than other operator groups (p < 0.05). Interestingly, no statistical difference in quality of root canal filling was noted between 5th year students, GPDs and endodontists. The treatment of lower teeth demanded statistically more visits than that of upper teeth (p < 0.05). The results of the study emphasize that most of the root canal filling performed by operators was considered adequate, regardless of tooth type, files used and number of visits.

Accessory mental foramen (AMF) is a rare anatomical variation. When accessory mental foramen is present, the nerves and vessels that go through the mental foramen (MF) must follow alternative courses and special care must be taken during dental treatment planning. The purpose of this study was to evaluate the occurrence and the location of AMF in a selected Polish population using cone-beam computed tomography (CBCT). Two hundred CBCT (105 males and 95 females) examinations were evaluated for the presence of AMFs. The location and side of AMFs were reported. The mean distance between MF and AMF was also calculated. The vertical size of MF on the side with and without AMF was measured. The obtained variables were statistically analyzed. AMFs were observed in 7% of the patients. There was no statistically significant difference between the appearance of AMF and sex (p > 0.05). We found no significant difference in the vertical size of MF between individuals with and without AMFs (p < 0.05). Twenty-eight AMFs (7%) were observed from 400 sides of 200 patients. AMFs occurred more often in males (18 AMFs) than in females (10 AMFs). Twenty AMFs (71.4%) were located anteriorly, and eight (28.6%) - posteriorly. Fifteen AMFs (53.6%) were on the right side and thirteen (46.4%) - on the left.

Metals subjected to the oral environment are prone to corrosion over time and this can be harmful. Metallic restoration components such as dental subgingival implant abutments are exposed to pH changes and different ions while in contact with saliva. The aim of the study was to evaluate the corrosion resistance of titanium dental implant abutments and to compare and contrast the surface characteristics of these alloys before and after corrosion. The corrosion examination (E_corr, j_corr, OCP, polarization curve) of two implant abutments (TiDesign EV, Astra Tech, Dentsply, York, PA, USA; Individual Titanium Abutment, Apollo Implants Components, Pabianice, Poland) was performed in 0.9% NaCl and 5% HCl. Moreover, specimens were investigated using SEM-EDS before and after the corrosion test. The value of j_corr in NaCl was higher for Astra (34.2 × 10⁻⁸ ± 2.5 × 10⁻⁸ A/cm²) than for Apollo (8.8 × 10⁻⁸ ± 2.5 × 10⁻⁸ A/cm²). Whereas, in HCl, the opposite relationship was observed (Astra 2.9 × 10⁻⁴ ± 0.8 × 10⁻⁴ A/cm² and Apollo 62.7 × 10⁻⁴ ± 9.3 × 10⁻⁴ A/cm²). An average reactive anodic current density in NaCl for Astra amounted up to ~0.2 × 10⁻⁵–1.5 × 10⁻⁵ A/cm², while for Apollo-up to ~3.3–9.7 × 10⁻⁷ A/cm². The composition of both alloys after corrosion in NaCl demonstrated some changes: a decrease in the Ti, and Al and an increase in oxygen content. Hence, both alloys after corrosion in HCl demonstrated some minor changes in the elemental composition. Based on the results it can be concluded that: 1. Astra and Apollo abutments revealed good corrosion resistance and a passivation layer on the surface. 2. Apollo abutments exhibited better corrosion resistance in a neutral environment, suggesting that Astra abutments were found to be more resistant to corrosion in an acidic medium.

The assessment of microgaps at the implant–abutment interface is an important factor that may influence clinical success. Thus, the aim of this study was to evaluate the size of microgaps between prefabricated and customised abutments (Astra Tech, Dentsply, York, PA, USA; Apollo Implants Components, Pabianice, Poland) mounted on a standard implant. The measurement of the microgap was performed using micro-computed tomography (MCT). Due to 15-degree rotation of samples, 24 microsections were obtained. Scans were performed at four levels established at the interface between the abutment and the implant neck. Moreover, the volume of the microgap was evaluated. The size of the microgap at all measured levels varied from 0.1 to 3.7 µm for Astra and from 0.1 to 4.9 µm for Apollo (p > 0.05). Moreover, 90% of the Astra specimens and 70% of the Apollo specimens did not exhibit any microgaps. The highest mean values of microgap size for both groups were detected at the lowest portion of the abutment (p > 0.05). Additionally, the average microgap volume was greater for Apollo than for Astra (p > 0.05). It can be concluded that most samples did not exhibit any microgaps. Furthermore, the linear and volumetric dimensions of microgaps observed at the interface between Apollo or Astra abutments and Astra implants were comparable. Additionally, all tested components presented microgaps (if any) that were clinically acceptable. However, the microgap size of the Apollo abutment was higher and more variable than that of the Astra one.