Journal of Clinical and Experimental Dentistry最新文献

Background: To determine the prevalence and primary radiographic characteristics of impacted mandibular second molars in Peruvian individuals using panoramic radiographs.Material and methods: This cross-sectional study examined 1,000 digital panoramic radiographs of young adults aged 15 to 40 years in Lima, Peru, conducted from 2022 to 2024. These radiographs were evaluated individually for each side, for a total of 2000 sides evaluated. Two trained evaluators performed the measurements. The selected radiographs included complete lower dentition and demonstrated good contrast and clarity. We evaluated the presence of second molar impaction and the level of impaction (coronal, cervical, or radicular). The direction of impaction was also assessed and categorized as vertical, mesioangular, distoangular, horizontal, inverted, or transverse. Additionally, the relationship between the third molar and whether the impaction was unilateral (right or left) or bilateral were evaluated. Data analysis was performed using IBM SPSS Statistics version 29.0, applying Fisher's exact test, chi-square test, and logistic regression (p<0.05).

Results: The sample consisted of 514 females (mean age, 26.79 ± 10.12 years) and 486 males (mean age, 26.26 ± 9.76 years). The prevalence of impaction was found to be 6%. Among the impacted cases, females represented the majority (61.67%) compared to males (28.33%). The most frequently observed level of impaction was coronal (78.8%), followed by cervical (16.5%) and radicular (4.7%). The predominant angulation was mesioangular (71.8%), followed by distoangular (16.5%), vertical (7.1%), and horizontal (4.7%). Unilateral impaction was fairly distributed between the right side (28.3%) and left side (30%), while bilateral impaction was observed in 41.7% of cases.

Conclusions: The prevalence of impacted second molars in our study was significant and has a considerable impact on orthodontic clinical practice. This issue was more common in females, with most cases occurring at the coronal level. The most frequent orientation of impaction was mesioangular, and unilateral cases were more common than bilateral ones. Key words:Prevalence, Mandible, Tooth eruption, Panoramic radiograph, Molar tooth.

Background: Provisional restorations play a fundamental role in fixed prosthodontic rehabilitation. While current evidence has identified CAD/CAM-fabricated materials as the preferred option due to their excellent mechanical properties, 3D-printed resins have shown significant improvements in their performance in recent years. Therefore, the aim of the present study was to re-evaluate the fracture resistance of provisional crowns fabricated using 3D-printed resin and CAD/CAM-milled PMMA, considering the influence of artificial aging.

Material and methods: An in vitro study was conducted on 60 provisional crowns divided into four groups according to material type (3D-printed resin or CAD/CAM PMMA) and aging condition; thermocycling and simulated brushing were applied, fracture resistance was tested using a universal testing machine, and data were analyzed using the Student's t-test at a 5% significance level.

Results: After artificial aging, 3D-printed restorations showed significantly higher fracture resistance than CAD-CAM milled crowns (p = 0.0064). However, no statistically significant differences were observed between the two fabrication methods under non-aged conditions (p > 0.05). All groups exceeded the minimum values considered clinically accepTable.

Conclusions: 3D printing demonstrated superior mechanical stability after artificial aging, supporting its clinical viability as an efficient, predicTable, and favorable option for provisional restorations in oral rehabilitation. Key words:3D printing, CAD/CAM, Digital dentistry, Provisional restoration, fracture resistance.

Background: Bioactive resins can release fluoride ions, but their potential for fluoride recharge is unknown. This study aimed to evaluate the fluoride (F) release and recharge capacity of bioactive resins using an in vitro pH cycling model.

Material and methods: Six specimens were prepared for each group: two bioactive resins (Beautifil Flow Plus and Biocoat), a conventional resin (Opallis Flow), and a resin-modified glass ionomer cement (Ionoseal). For pH cycling, each specimen was immersed in an acidic solution (Sprite, pH 3.6) for 6 hours at 37 °C, rinsed with distilled water, and then stored in artificial saliva (pH 7.0) for 18 hours. This cycle was repeated for three consecutive days. Afterward, the samples were brushed with fluoride toothpaste and subjected to a second pH cycling phase. For F determination, 1 mL of TISAB was added to each solution, and fluoride levels were measured using an ion-selective electrode. Data were tested for normality using the Shapiro-Wilk test and analyzed by one-way ANOVA followed by Tukey's post hoc test.

Results: In the initial fluoride release phase, Beautifil resin demonstrated similar performance to Ionoseal and exhibited a significantly higher fluoride release compared to the other materials (p < 0.05). However, during the recharge phase, Ionoseal demonstrated superior fluoride release compared to all other materials (p < 0.05).

Conclusions: Beautifil resin and Ionoseal exhibited the highest fluoride release in both phases of pH cycling when compared to the other materials. Nevertheless, Ionoseal outperformed the others in fluoride recharge following treatment with fluoridated dentifrice. Key words:Fluorides, Bioactive Resin, Dental Materials.

Low-grade myofibroblastic sarcoma (LGMS) is an extremely rare mesenchymal neoplasm. It arises from the differentiation of myofibroblasts and demonstrates a preference for the head and neck region. Herein, we present a case of LGMS in a 52-year-old man with painless swelling in the anterior right area of the tongue. Histologically, the lesion consisted of spindle-shaped cells exhibiting mild to moderate nuclear atypia, arranged in fascicles with a storiform pattern. Neoplastic cells were positive for SMA and negative for EMA, CD34, h-caldesmon, desmin, β-catenin, S100, SOX10, and NF, with a Ki-67 index of 15-20%. Complete surgical excision with clear margins was the treatment of choice. Very few cases of LGMS have been documented in the literature, and regular follow-up for these patients is essential for drawing reliable conclusions regarding local recurrence and the metastatic potential of this tumor. Key words:Low-grade, myofibroblastic, sarcoma, tongue, myofibroblasts, immunohistochemistry.

Background: Alcohol in some mouthwashes can dissolve the polymer chain of resin composites, potentially altering their properties. The aim was to evaluate the color stability of resin composites immersed for 24 hours and 7 days in alcohol-based and alcohol-free mouthwashes.

Material and methods: This experimental, longitudinal, in vitro study included 90 resin composite discs divided into three equal groups (n = 30): Filtek Z350XT, Tetric N-Ceram, and Opallis. Each group was split into two equal subgroups (n = 15) and immersed in Listerine Zero and Listerine Cool Mint. Color variation was recorded with a Vita Easyshade spectrophotometer after 24 hours and 7 days of immersion. Welch's robust ANOVA with an intergroup factor and Student's t-test for related samples were used, with significance set at p<0.05.

Results: There was no significant color variation when comparing the effect of alcohol-based and alcohol-free mouthwashes on each resin composite (Opallis, Tetric N-Ceram, and Filtek Z350XT) at both 24 hours (p>0.05) and 7 days (p>0.05), although the average color variation in all samples exceeded the clinically accepTable threshold (ΔE > 3.3). When comparing resins immersed in alcohol-based mouthwash, Filtek Z350XT showed greater color variation at 24 hours (p<0.05) and 7 days (p<0.05). Tetric N-Ceram resin immersed in alcohol-based mouthwash significantly increased color variation (p = 0.036) between 24 hours and 7 days.

Conclusions: In this in vitro study, all evaluated resin composites showed color variation exceeding the clinically accepTable threshold. Filtek Z350XT was the most susceptible to color change following exposure to alcohol-based mouthwashes, while Tetric N-Ceram showed a significant increase in color variation between 24 hours and 7 days. These findings suggest that the presence of alcohol in mouthwashes could negatively affect the color stability of certain resin composites. Key words:Nanohybrid composite, comparative study, dental materials, resin composite, mouthwashes.

Background: Dental caries is a prevalent chronic disease in children that induces local inflammation and oxidative stress. Salivary biomarkers offer a non-invasive tool for monitoring biological changes associated with dental interventions. This study aims to evaluate pre- and post-treatment changes in salivary biomarkers of inflammation and oxidative stress in children with caries and to synthesize evidence on the biological response to treatment.

Material and methods: This systematic review and meta-analysis followed PRISMA 2020 guidelines and was prospectively registered in PROSPERO. A comprehensive literature search identified longitudinal and pre-post studies assessing salivary biomarkers in pediatric caries patients treated with restorative or preventive interventions. Risk of bias was assessed using ROBINS-I, and evidence quality with GRADE. Meta-analysis was conducted using a random-effects model.

Results: Six studies involving 202 children (aged 3-12) were included. The pooled standardized mean difference (SMD) was 0.51 (95% CI: 0.37-0.65), favoring a post-treatment improvement in biomarker levels. Heterogeneity was moderate (I² = 45.6%; τ² = 0.012). ROBINS-I indicated moderate risk of bias; GRADE rated overall certainty of evidence as moderate.

Conclusions: Therapeutic dental interventions in children with caries are associated with measurable improvements in salivary biomarkers, suggesting reduced inflammation and oxidative stress following treatment. Key words:Dental Caries, Saliva, Biomarkers, Oxidative Stress, Pediatrics.

Background: Repair of resin composite restorations consists in a more conservative solution compared to complete replacement. The objective of the present study was to evaluate different surface treatment protocols and their effects on the adhesive interface between the base and the repair resin composite, considering both new and aged restorations.

Material and methods: This study evaluated six resin composites (Admira Fusion Xtra/ADM, Filtek Supreme Flowable/FSF, Filtek One/FO, Vitra/VIT, Filtek Supreme/FS, Filtek Bulk Fill Flowable/FBF), five surface treatments (Hydrofluoric acid 120s+silane/HFs, Phosphoric acid 30s/P30, Phosphoric acid 30s+silane/P30s, Sof-lex+phosphoric acid 30s/SP30, Sof-lex+phosphoric acid 30s+silane/SP30s), and two repair timepoints (immediate and after 1 year simulated aging aged). Forty disks for each resin were divided into 10 groups according to surface treatment and repair timepoints (n=4 disks per subgroup). Surface treatments were performed, followed by application of a universal bonding agent (Scotchbond Universal). Filtek Supreme/FS was used as the repairing resin, and three cylinders of material were cemented on each resin disk. Notched shear bond strength test was performed using a universal testing machine, contact angle tests were performed using a goniometer, and fracture mode analysis was performed using a stereomicroscope.

Results: All factors and their interactions were significant for both shear bond and contact angle tests (p<.001 for all criteria). Overall results for shear bond strength showed SP30=SP30s>P30=P30s>HFs; immediateVIT>FBF=FSF>ADM. Similarly, overall results for contact angle showed P30>HFs>SP30; aged>immediate; and FSF>VIT=FBF>FS=FO>ADM. Immediate resin samples treated with mechanical roughening exhibited lower number of adhesive failures compared to other treatments. In aged samples, groups treated with mechanical roughening and/or silane agent showed a predominance of cohesive and/or mixed failure modes. Shear bond strength is influenced by the type and age of the base resin composite, as well as the surface treatment applied.

Conclusions: Despite a tendency for higher results when mechanical roughening is associated with Scotchbond Universal, there is not a clear difference to justify its use in most of the resin composites. Furthermore, most of the surface treatments performed similarly, regardless of the base resin composite. Key words:Resin composite, resin repair, surface treatments, bulk-fill composite, adhesive interface.

Background: This study investigated the relationship between the occlusal plane and the ala-tragus lines (ATL) for restoring the upper and lower jaws and analyzed the ATL in different jaw classifications.

Material and methods: This analytical cross-sectional study included lateral cephalometric radiographs of 172 patients with teeth in a normal position. The three ATLs and the occlusal plane were delineated, and jaw classification was determined using Waits and Steiner analysis.

Results: For jaw classes 1 and 2, the parallelism between the lower ATL and the occlusal plane was not statistically significant. However, for class 3 patients, significant parallelism was observed between the lower ATL and the occlusal plane, regardless of the maxillary classification. In the gender-based analysis, the parallelism between the occlusal plane and the lower ATL was significant for women. In the age-based analysis, the parallelism was significant in the age group of 15-21 years.

Conclusions: These findings suggest that the lower ATL can be a reliable reference for determining the occlusal plane. The study also highlights that age and gender are important factors influencing the determination of the occlusal plane using the ATL. Key words:Occlusal plan, ala-tragus line, cephalometric radiograph.

Background: This study evaluated the effectiveness of ultrasonic agitation in removing residual root canal filling material (RFM) from mandibular molars with isthmuses and to assess the influence of different bioceramic endodontic sealers, Bioroot RCS (BCS), and EndoSequence BC Sealer (ESBC).

Material and methods: Forty human mandibular molars were prepared with Reciproc R25 and divided based on the obturation material. The retreatment was performed (Reciproc R40) and the roots were randomly divided between agitation protocols (PUI/CUI) using a large solution volume (60 mL/canal).

Results: The percentage reduction of RFM was measured after agitation. Ultrasonic agitation resulted in a percentage reduction of RFM ranging from 54.39% to 68.10% in the total area, and from 56.25% to 73.21% in the apical third (P < .05). No significant differences were found related to sealer type or activation protocol (P > .05).

Conclusions: While none of the protocols completely removed RFM, ultrasonic agitation proved effective in its reduction, independent of the sealer presentation and agitation method used. Key words:Endodontics, Ultrasonic Agitation, Root Canal Irrigants, Root Canal Filling, X-ray Microtomography.

Background: This study aimed to evaluate the performance of CAD/CAM milled, universal 2-piece and anatomical fiber posts in comparison with prefabricated fiber posts in root canals with varying degrees of structural compromise, using fracture resistance (FR) testing and failure mode analysis.

Material and methods: Seventy mandibular premolars were selected, trimmed 2 mm above the cementoenamel junction, and subjected to endodontic treatment. The specimens were divided into seven groups based on the type of restorative approach (prefabricated, anatomical, CAD/CAM milled, and universal 2-piece fiber posts) and the extent of root weakening (no weakened, moderately weakened, and severely weakened). RelyX U200 cement was used for post luting, followed by the fabrication and cementation of metal-free crowns. Failure rates and patterns were evaluated, with statistical analysis performed using Student's t-test, two-way ANOVA, Tukey's post hoc test, and chi-square tests to compare failure mode frequencies.

Results: The findings revealed that CAD/CAM milled and universal 2-piece fiber posts demonstrated significantly higher fracture resistance compared to anatomic fiber posts. Moderately weakened (MW) specimens outperformed severely weakened (SW) ones. All experimental groups exhibited fracture resistance comparable to the control group, except for the MW-MFP group, which exceeded the control. The majority of fractures were repairable, and no significant association was observed between failure mode and the type of restorative approach or the degree of root weakening.

Conclusions: CAD/CAM milled and universal 2-piece fiber posts offer strong fracture resistance and predominantly repairable failure modes, making them suiTable alternatives for restoring weakened roots. Key words:Resin Cements, CAD-CAM, Post and Core Technique, Root Canal Preparation.