Dentistry Journal最新文献

Objectives: This study evaluated and compared the sealing ability and elemental composition of a resin-based endodontic sealer (AH Plus) used with three root canal obturation techniques: single cone (SC), lateral compaction (LC), and warm vertical condensation (WVC). The investigation focused on microstructural characteristics, interfacial integrity, and elemental distribution within filled root canals. Material and Methods: Sixty extracted single-root teeth were instrumented using the ProTaper Gold system and randomly assigned to three groups (n = 20) according to the obturation technique. The AH Plus Jet sealer was applied in all cases. Following obturation, samples were subjected to radiographic investigation and analyzed using optical microscopy and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) to assess the sealing performance and chemical composition. Results: Radiographic and microscopic assessments indicated that the SC method showed strong gutta-percha adhesion to dentin with a thin cement layer, whereas WVC provided excellent adaptation and penetration of gutta-percha. The LC technique demonstrated good adhesion but displayed occasional structural irregularities. SC has the thicker adhesion layer with uneven distribution regarding coronal, median, and apical, regions ranging from 45 to 80 μm, while WVC ensures a thin and uniform sealing layer of about 35 μm in all regions. SEM and EDX analyses detailed the interfacial microstructure and confirmed the presence of carbon (C), oxygen (O), calcium (Ca), zinc (Zn), barium (Ba), and sulfur (S) across all groups. Conclusions: All three obturation techniques (SC, WVC, LC) achieved effective sealing when combined with the AH Plus sealer. The main difference between the methods consists of the sealer layer thickness and its even distribution regarding gutta-percha cones.

Background: Smoking has a detrimental effect on the periodontal condition. Smoking intensity has recently been considered as a criterion for grading periodontitis cases. However, the influence of smoking intensity on the subgingival microbial community has not been evaluated in depth. This cross-sectional analytical study aims to assess the differences in the subgingival microbiome in adult patients with chronic periodontitis and different smoking habits (heavy smokers versus moderate smokers versus non-smokers). Methods: Sixty patients diagnosed with chronic periodontitis were grouped according to their daily smoking intensity as follows: group I (smoke ≥ 10 cigarettes/day), group II (smoke < 10 cigarettes/day), and non-smokers (group III). For each patient, samples from subgingival plaque were harvested from the deepest three periodontal pockets, and their 16S rRNA was sequenced using the S5 Ion Torrent platform. Sequences were clustered in taxonomic units, and the microbial diversity was expressed using the Shannon index or Simpson index, while the abundance of the microbial species was expressed using the Chao index. Results: Bacterial diversity was lowest in the heavy smoker group (group I) and highest in non-smokers (group III). Veillonella, Streptococcus, Prevotella, Fusobacterium, and Dialister were found to have different prevalences in the three study groups. Campylobacter decreased and Fusobacterium increased as a function of the number of cigarettes smoked per day. The moderate smoker group showed a higher abundance of Spirochaetes. At the species level, the heavy smoker group (group I) showed a higher abundance of Fusobacterium compared to the other two groups. Conclusions: Greater smoking intensity has been associated with higher Fusobacterium abundance, together with decreased diversity of the subgingival microbiome, establishing a more stable putative subgingival bacterial environment.

Background/Objectives: Tooth loss is a key marker of ageing and is linked to functional, psychological, and nutritional decline. Removable dental prostheses (RDPs) are widely used, yet their impact on life satisfaction and oral health-related quality of life (OHRQoL) remains uncertain. This study aimed to: (1) identify dental deficiencies in adults aged ≥50 years; (2) assess the use of RDPs; and (3) examine the relationship between prosthetic status, life satisfaction, and OHRQoL. Methods: This retrospective cross-sectional analysis included 986 participants from the Białystok PLUS cohort (2018-2024). Dental examinations classified individuals into: Group 0 (no deficiencies), Group 1 (deficiencies without prostheses), and Group 2 (deficiencies with RDPs). Life satisfaction was measured using the Satisfaction with Life Scale (SWLS), and OHRQoL using the Geriatric Oral Health Assessment Index (GOHAI). Analyses included Kruskal-Wallis test and correspondence analysis. Results: Partial mandibular deficiencies were the most frequent and were less often rehabilitated than maxillary defects. Most prostheses were mucosa-supported. Life satisfaction (mean SWLS = 22.4) did not differ significantly between groups (p = 0.326). In contrast, OHRQoL differed significantly (mean GOHAI = 53.8; p = 0.0001), supporting an effect of prosthetic status. Group 0 showed the highest GOHAI scores (55.7), while Group 2 (52.7) scored lower than Group 1 (53.0). Prosthesis users most often reported dissatisfaction with appearance and eating comfort. Conclusions: Life satisfaction appears independent of prosthetic status. OHRQoL, however, is strongly associated with dentition: individuals without deficiencies report the highest outcomes, whereas RDPs-especially mucosa-supported types-do not improve, and may reduce, perceived OHRQoL.

Background/Objectives: The purpose of this study was to assess the in vitro biocompatibility and corrosion resistance of five titanium alloys that have been recently developed for dental implant applications, whose compositions were designed to align with current approaches in the development of novel biomaterials. Priority was given to limiting the harmfulness associated with specific chemical elements present in common conventional alloys and increasing corrosion resistance to improve the biomaterial-tissue cellular interaction. Methods: For this purpose, five types of titanium alloys with original chemical compositions (Ti1-Ti5) were developed. The electrochemical behavior of the alloys was analyzed by evaluating the corrosion resistance in environments that simulate the oral environment, as well as the cellular behavior, by evaluating the viability, growth, and proliferation of human cells on osteoblasts and gingival fibroblasts. Detailed analysis of the chemical composition by scanning electron microscope (SEM/EDS) methods was used. The corrosion rate of the alloys in artificial saliva was tested using the polarization resistance technique (Tafel). Human osteoblasts (hFOB cell line) and human gingival fibroblasts (hFIB-G cell line) were used to measure biocompatibility in vitro. Results: The Ti5 alloy demonstrated the highest cell viability and the lowest corrosion rate (0.114 μm/year) among all tested compositions, with the Ti3 alloy containing Mo and Zr following closely behind. The Ti2 alloy exhibited reduced biocompatibility because of the inclusion of Ni and Fe in its composition. Conclusions: Taken together, the results of this study provide useful information on the basic characteristics of titanium alloys with original chemical compositions. The titanium alloys were analyzed in comparison with common conventional alloys (Cp-Ti and Ti6Al4V) as well as alloys such as Ti-Zr, Ti-Nb, and Ti-Nb-Zr-Ta, which are considered to be viable alternatives to conventional materials for making dental implants.

Background: Facial fractures are common in emergency and trauma care, with age and sex known to influence fracture patterns, injury mechanisms, and treatment approaches. However, detailed comparative data analyzing these demographic variables separately remain limited. Methods: In this retrospective single-center study, we analyzed 561 patients with radiologically confirmed facial fractures who were treated between January 2021 and December 2022. Patients were stratified by sex and age (<50 vs. ≥50 years). Fracture types, trauma causes, and treatment modalities were compared using odds ratios (ORs) with 95% confidence intervals (CIs). Results: Male patients comprised 60.1% of the cohort. Interpersonal violence, alcohol-related trauma, and sports injuries were significantly more frequent in males, while females experienced more falls and syncopes (p < 0.001). Although most fracture types did not differ significantly by sex, female patients underwent surgical treatment significantly less often than males (OR = 0.45, 95% CI: 0.32-0.64, p < 0.001). Patients over 50 years were significantly less likely to suffer mandibular fractures (OR = 0.59, 95% CI: 0.40-0.88, p = 0.009), while frontal sinus fractures were more common in older individuals (OR = 4.77, 95% CI: 1.02-22.27, p = 0.029). Younger patients more often experienced interpersonal violence, alcohol-related incidents, and received operative care, whereas falls and conservative treatment were more frequent among older individuals. Conclusions: Age and sex significantly influence the epidemiology and management of facial fractures. Understanding these demographic differences can guide targeted prevention strategies and assist clinical decision-making in facial trauma care.

Background/Objectives: There is evidence of possible contamination of prosthetic components originating from dental laboratories. The aim of this study is to investigate the disinfectant effect of citric acid and polyethylene glycol on implant-prosthetic materials in comparison with an untreated control and chlorhexidine. Methods: A total of 720 disks made of three different materials (titanium grade V, zirconia coated with feldspathic ceramic, and PMMA) contaminated with three bacteria (Staphylococcus aureus, Enterococcus faecalis, and porphyromonas gingivalis) were analyzed. Four treatment groups were tested: citric acid, polyethylene glycol, chlorhexidine and an untreated control group. Two assessment periods (3 and 21 days of incubation) were used, with bacterial metabolic activity measured using the resazurin reduction test and then analyzed by electron microscopy. Results: The results show that chlorhexidine has a superior inhibitory effect on all materials and bacterial strains in the short-term evaluation (3 days), while citric acid and polyethylene glycol showed higher efficacy after 21 days. Citric acid also exhibits differential effects when applied to grade V titanium. These differences were statistically significant at p < 0.05. Conclusions: There is evidence to recommend chlorhexidine for the disinfection of laboratory prosthetic components, but the enhanced effect of citric acid on grade V titanium and its long-term efficacy make it clinically promising candidate.

Background/Objectives: Chipping of the veneering part of the crown at the zirconia-porcelain interface remains a major complication of bilayered zirconia systems. This systematic review evaluated whether incorporating a lithium-disilicate (LD) liner or press-on or CAD-on interlayer between zirconia and veneer improves bond strength and fracture performance in vitro. Methods: Following PRISMA 2020, we searched PubMed, Scopus, and Web of Science up to 7 September 2025 for open-access English in vitro studies using LD-based interlayers at zirconia-veneer interfaces and reporting quantitative bond and/or fracture outcomes. Data included extracted materials, processing parameters, and mechanical results; due to heterogeneity, findings were synthesized descriptively and as the ratio-of-means (ROM). Results: Five in vitro studies from Korea, Thailand, and India met the criteria. LD interlayers increased microtensile bond strength from 18.83 to 44.20 MPa and from 19.6 to 47.7 MPa, and shear bond strength from 41.3 to 59.7 MPa, 11.40 ± 1.29 to 18.81 ± 1.76 MPa, and 21.5 to 60.2 MPa. Corresponding ROMs ranged from 1.46 to 2.80 (median 2.35), with thermocycled LD groups maintaining strengths >25 MPa. LD liners also raised crown fracture loads from ~2.18 to ~3.45 kN and characteristic strength from 3.42 to 5.64 kN, while chipping loads in implant crowns increased from ~0.34 to ~0.84 kN and global fracture from ~1.71 to ~1.93 kN. Conclusions: Across diverse zirconia-veneer configurations, LD interlayers consistently enhanced bond metrics and fracture/chipping resistance, supporting their use as a targeted interfacial strategy; however, clinical confirmation is still needed.

Background/Objectives: Super translucent zirconia (ST zirconia) is increasingly used for esthetic restorations, but its optical stability after mechanical wear remains unclear. This study aimed to evaluate the effects of three finishing protocols-polishing, glazing, and staining followed by glazing (Chroma + Glaze)-on the color stability and translucency of ST zirconia after simulated toothbrushing. Methods: Sixty zirconia specimens (Vita YZ ST, shade A1) were fabricated and divided into three groups, namely Polished, Glazed, and Chroma + Glaze (n = 20 in each group). Color (L*, a*, b*) was measured using a spectrophotometer (VITA Easyshade V; VITA Zahnfabrik) before and after 10,000 brushing cycles (200 g load, 1.5 Hz). Translucency parameters (TP_ab, TP₀₀) were calculated, while color changes were assessed using CIELAB (ΔE_ab) and CIEDE2000 (ΔE₀₀) formulas. Data were analyzed using two-way ANOVA and Kruskal-Wallis tests (α = 0.05). Results: Treatment significantly affected translucency (H = 46.79, p < 0.001; H = 21.09, p < 0.001), indicating consistent differences among the three treatment groups. Bonferroni-adjusted post hoc comparisons showed that Chroma + Glaze exhibited significantly lower TP₀₀ values than Glaze in both measurements (p < 0.0001; p < 0.001), as well as lower values than Polished in both measurements (p < 0.0001; p = 0.0147, respectively). Kruskal-Wallis analysis revealed significant differences among finishing protocol groups for both ΔE_ab (H = 13.21, p < 0.0014) and ΔE₀₀ (H = 9.14, p = 0.0104), with Chroma + Glaze exhibiting the smallest ΔE values (ΔE₀₀ ≈ 0.33) below the perceptibility threshold. Conclusions: The finishing protocol significantly influences the optical behavior of ST zirconia after simulated wear. The Chroma + Glaze group demonstrated the highest color stability and lowest translucency, suggesting enhanced long-term esthetic performance. In contrast, polished zirconia showed greater color variation and an increase in translucency, indicating lower optical stability under brushing abrasion.

Background/Objectives: Augmented Reality (AR) is promising in dental education, yet its impact on caries detection training remains underexplored. This study aimed to compare the effect of a web-based AR (WebAR) learning object with a content- and interface-matched interactive 2D presentation on undergraduate students' motivation to learn caries detection. Methods: Two learning objects were expressly designed using a real patient's dental records: a WebAR image-tracking experience (built with Zapworks Studio^®) and a 2D interactive presentation (built with Genially^®). The WebAR object showed the patient's 3D dental arches with tooth-level hotspots linking clinical and radiographic media. The 2D comparator mirrored the same assets and navigation, restricting visualization to 2D. Third-year dental students were randomly assigned to either the AR or Genially^® (G) group. After completing ICDAS-based caries identification, participants completed the 12-item Reduced Instructional Materials Motivation Survey (RIMMS) and provided open-ended feedback. Group differences were tested with the Mann-Whitney U test (p < 0.05). Results: Eighty-five students completed the study (AR n = 46; G n = 39). The AR group achieved a higher total RIMMS score (4.14 vs. 3.53 on a 5-point scale; p < 0.001), with significantly higher means in Attention, Confidence, Satisfaction, and Relevance (p < 0.05). Open-ended comments were more positive with AR (75.8% vs. 31.0%), while graphics-related complaints were more frequent with the Genially^® resource (34.5% vs. 75.0%). Conclusions: WebAR achieved higher RIMMS motivation scores than a content-matched interactive presentation. Adding 3D spatial interaction to otherwise equivalent materials can enhance learners' motivation for caries detection training, while remaining low-cost and scalable.

Background/Objectives: This study aimed to investigate the effects of a new alcohol-free marine mouthwash containing an algae extract, a coastal plant extract, and seawater on plaque reduction, gingivitis, and oral microbiota balance. Methods: In a single-center, prospective, randomized comparative study, 50 subjects with gingivitis were assigned to either a marine mouthwash group (Test, n = 26) or a marketed mouthwash group (Comparator, n = 24). Clinical assessments included plaque, gingivitis, halitosis, and volunteer self-evaluation at baseline (T0) and after 7 days (T7). Gingival microbiota was sampled using swabs at baseline (T0) and after 7 days (T7). Conclusions: Both groups demonstrated reductions in dental plaque, gingivitis, and halitosis at T7 compared to baseline. Improvements in halitosis were observed in both groups but did not reach statistical significance. Microbiota analysis revealed that the Test group experienced the enrichment of health-associated bacterial taxa and a reduction in disease-associated species, notably Porphyromonas endodontalis, while the Comparator group showed an increase in pathogenic taxa. The marine mouthwash was well tolerated and positively rated by participants. Combining an algae extract, a coastal plant extract, and seawater, it effectively reduces plaque and gingivitis and may contribute to oral microbiota balance. It represents a promising alternative to conventional chemical oral care products.