Search Results (250)

Background/Objectives: Among the paranasal sinuses, the maxillary antrum holds unique clinical relevance due to its proximity to the alveolar process of the maxilla, which houses the teeth. This study aimed to evaluate the position of the root apices of the maxillary canines and posterior teeth relative to the maxillary sinus floor in Romanian subjects. Methods: Data for the study were retrospectively obtained from cone-beam computed tomography (CBCT) scans. The evaluation considered the pattern of proximity to the sinus floor for each tooth type, comparisons of the sinus relationships of teeth within the same dental hemiarch, as well as those of homologous teeth, and variation in root-to-sinus distance in relation to sex and age. Nonparametric tests were used for statistical analysis, and multiple comparisons were performed using Bonferroni post hoc correction. Results: The study included 70 individuals aged 20 to 60 years. The distance to the sinus floor decreased progressively from the first premolar to the second molar, with median values of 3.68 mm (first premolar), 1.45 mm (second premolar), 0.50 mm (first molar), and 0.34 mm (second molar) (p < 0.01). Stronger correlations were observed between adjacent teeth than between non-adjacent ones. The distances to the sinus floor were greater on the right side compared to the left; however, these differences were not statistically significant (p > 0.05 for all teeth). Concordance between left and right dental hemiarches regarding the closest tooth to the sinus floor was found in 70% of cases (n = 49), most frequently involving the second molars (n = 38; 54.3%). On average, the distance from the sinus floor was smaller in males compared to females, with statistically significant differences observed only for the second molar. Increased age was associated with a greater distance to the sinus floor. Conclusions: Of all the teeth investigated, the second molar showed the highest combined prevalence of penetrating and tangential relationships with the maxillary sinus. At the dental hemiarch level, the second molar was most frequently the closest tooth to the sinus floor, and in the majority of cases, at least one posterior tooth was located within 0.3 mm. Accurate preoperative assessment of tooth position relative to the sinus floor is essential when performing non-surgical or surgical root canal therapy and extractions of maxillary molars and premolars. CBCT provides essential three-dimensional imaging that improves diagnostic precision and supports safer treatment planning for procedures involving the posterior maxilla. Full article

Fiber-reinforced composites (FRCs) are recognized for enhancing the fracture resistance of structurally compromised teeth. However, the optimal orientation and placement of fibers in direct resin composite restorations remain under debate. This study aimed to evaluate the fracture resistance of maxillary premolars with mesio-occluso-distal (MOD) cavities restored using polyethylene fibers with different placement techniques, compared to conventional incremental composite restoration. Methods: Sixty intact maxillary premolars were randomly assigned to six groups (n = 10). Group 1: intact teeth (positive control); Group 2: MOD cavity without restoration (negative control); Group 3: MOD cavity restored with nanohybrid composite using the incremental technique; Group 4: polyethylene fiber placed on the pulpal floor; Group 5: fiber placed circumferentially along cavity walls (wall-papering technique); Group 6: fiber placed buccolingually in an occlusal groove (occlusal splinting). Fracture resistance was assessed using a universal testing machine. Failure mode was also analyzed. Results: Group 6 (occlusal splinting) exhibited the highest fracture resistance (1137.72 ± 316.20 N), significantly exceeding Group 3 (546.93 ± 59.89 N) and other fiber-reinforced groups (p < 0.05). Failure mode analysis revealed no significant differences between the fiber-reinforced groups and the intact teeth. Group 6 also had the highest percentage of restorable fractures (90%). Conclusions: Incorporating polyethylene fibers, especially through occlusal splinting, significantly improves fracture resistance in MOD-restored maxillary premolars. This technique may offer a promising alternative to conventional composite restorations in structurally weakened posterior teeth. Full article

Cosmetic restorative dentistry focuses on restoring teeth affected by caries or trauma using materials that mimic natural teeth in shape, texture, and color. Composite resins, particularly nanofilled composites, are widely used due to their superior mechanical and aesthetic properties. Accurate tooth color selection is crucial, and methods include visual (shade guides) and instrumental (spectrophotometers, colorimeters, and intraoral scanners). Newer biomimetic composites, such as Admira Fusion 5 and Clearfil Majesty ES-2 Universal, simplify shade selection through advanced optical technologies. A randomized clinical study involving 30 patients compared the color-matching accuracy of two biomimetic composite resins: Admira Fusion 5 (Voco) and Clearfil Majesty ES-2 Universal (Kuraray). The study utilized the Vita Easyshade spectrophotometer and the Primescan intraoral scanner. Patients were treated following standardized protocols, and shade accuracy was evaluated pre- and post-restoration using Cohen’s Kappa index. Admira Fusion 5 showed higher shade-matching accuracy, with good agreement between pre- and post-restoration measurements using both instruments. Clearfil Majesty ES-2 Universal demonstrated lower reproducibility in shade matching, particularly in posterior teeth, with lower agreement in pre- and post-tests. Instrumentation Comparison: Primescan showed slightly better performance than Easyshade, but both provided comparable results. In conclusions, universal composites may not always achieve optimal shade matching in posterior teeth. Layered composites provide better color adaptability. While digital instruments enhance shade accuracy, combining them with visual methods yields the best clinical outcomes. Further research with larger sample sizes is needed to improve shade-matching techniques in aesthetic restorative dentistry. Full article

Although the manual classification of microfossils is possible, it can become burdensome. Machine learning offers an alternative that allows for automatic classification. Our contribution is to use machine learning to develop an automated approach for classifying images of Pectinodon bakkeri teeth. This can be expanded for use with many other species. Our approach is composed of two steps. First, PCA and K-means were applied to a numerical dataset with 459 samples collected at the Hanson Ranch Bonebed in eastern Wyoming, containing the following features: crown height, fore-aft basal length, basal width, anterior denticles, and posterior denticles per millimeter. The results obtained in this step were used to automatically organize the P. bakkeri images from two out of three clusters generated. Finally, the tooth images were used to train a convolutional neural network with two classes. The model has an accuracy of 71%, a precision of 71%, a recall of 70.5%, and an F1-score of 70.5%. Full article

This study evaluates the optical properties and mechanical durability of adhesive restorations fabricated using different techniques for the treatment of single-tooth loss in the posterior region after an aging process. Sixty extracted human teeth (thirty molars and thirty premolars) were restored using three different fabrication methods: 3D-printed resin restorations, fiber mesh-reinforced direct composite restorations, and indirect composite restorations. Color stability was assessed using a spectrophotometer, and fracture resistance was measured using a universal testing machine. Finite element stress analysis (FEA) was conducted to validate mechanical test results under simulated intraoral conditions. The fiber-reinforced composite group exhibited the highest fracture resistance (1057.91 MPa), while 3D-printed restorations showed the lowest (p < 0.05). Regarding color stability, the fiber-reinforced group demonstrated the highest ΔE⁰⁰ values (ΔE⁰⁰ = 1.71), differing significantly from the other groups, while the 3D-printed and indirect composite restorations showed no significant difference. Mechanical test results were consistent with FEA findings. These results indicate that fiber reinforcement enhances mechanical durability in high-load-bearing areas, while 3D-printed restorations may not yet be suitable for posterior regions. However, their potential use in anterior restorations, where occlusal forces are lower, warrants further investigation to improve material properties. Full article

Zirconia crowns are employed in pediatric dentistry for the complete restoration of anterior and posterior deciduous teeth. They are considered the best option due to their esthetic appeal, high strength, biocompatibility, and resistance to wear and corrosion. This study aims to evaluate the physico-chemical, cytological, and microbial properties of zirconia crowns to determine their biocompatibility, safety for surrounding tissues, and effectiveness in preventing microbial influence on tooth tissue based on their biofilm deposition potential. XRD measurements were conducted to confirm the crown composition. For the microbiological examination, a quantitative assessment of the adhesion capacity of the analyzed strains and the formation of a mixed biofilm was performed using a Zeiss Cell Observer SD confocal microscope. This study used a mixed biofilm containing Streptococcus mutans (ATCC 25175), Lactobacillus rhamnosus (ATCC 9595), Candida albicans (ATCC 90028), and Candida albicans (ATCC 10231) to simulate the oral environment and the possible dynamics created between different types of microorganisms. A direct contact method was used to assess cytotoxic properties. The zirconia crown biomaterial shows a low ability to adhere to specific microorganisms, with L. rhamnosus predominating, indicating low clinical potential for causing inflammation of the tissues surrounding the crown. The cytotoxic properties of the biomaterial were found to be at level 2, indicating moderate cytotoxicity. Their biggest flaws are price and the need for passive fitting, which involves aggressive grinding; this is a potential limitation when it occurs in children, as their cooperation with the treatment can be difficult to guarantee. Full article

This study used geometric morphometrics to investigate the carapace features of Chinese mitten crabs (Eriocheir sinensis) from non-traditional/emerging origins (Zhenlai County and Bosten Lake) and identify differences in features relative to crabs from traditional origins (Yangcheng Lake). Thirty-five landmark data points on the crab carapace were extracted based on the geometric morphometrics landmark point approach and standardized to obtain the mean shape of the crabs from the three origins. The carapace morphologies of crabs from the three different origins varied. Compared to the average morphology, the first lateral tooth of the carapace of the Zhenlai crab was shorter, and the M pattern was enlarged in males, whereas the first and second lateral teeth of the crabs from the other two origins were longer, and the M pattern was reduced. In female crabs, distinct morphological variations were observed across regions. In Zhenlai crabs, the lateral teeth were shorter, and the M pattern was enlarged. In Bosten crabs, the frontal tooth was shorter, the first and second lateral teeth were longer, and the posterior carapace margin was narrowed. In Yangcheng Lake crabs, the frontal and third lateral teeth were elongated, and the M pattern was narrowed. The discrimination accuracy of individual female and male crabs from different origins reached 100%. The results confirm that the carapace geometric morphometric method represents a convenient and non-lethal method of tracing E. sinensis origins in fine-scale production areas. Thus, this study provides guidance on developing a characteristic industrial chain for aquatic products of emerging origins, which may help to promote the sustainable development of the aquaculture industry in associated areas. Full article

The use of local anesthetics in dentistry is crucial for pain control. Their efficacy may be related to multiple factors, including gender, the clinical status of the patient, anatomical factors, the type of anesthetic, premedication treatment, and the experience of the professional. Aim: The objective of this study was to analyze whether premedication or the degree of patient anxiety influences the anesthetic efficacy of 4% articaine with epinephrine 1:100,000 and 0.5% bupivacaine with epinephrine 1:100,000 in patients undergoing root canal treatment for symptomatic irreversible pulpitis in the upper and lower molars. The null hypothesis (H0) of this study was that articaine and bupivacaine would have a similar anesthetic efficacy when used during the treatment of symptomatic irreversible pulpitis of the posterior mandibular and maxillary teeth, independent of non-steroidal anti-inflammatory drugs (NSAIDs) premedication or the patient’s anxiety levels. Methods: A total of 140 patients presenting with pulpitis in the upper and lower molars were randomly assigned to one of two anesthetics: articaine or bupivacaine. Before root canal treatment, patients completed the Modified Corah Dental Anxiety Scale (MDAS) and a Visual Analog Scale (VAS) for pain intensity. Inferior alveolar nerve block was performed for the lower molars and buccal infiltration for the upper molars, and the anesthetic efficacy was verified by the Endo Coldspray^® test. During the procedure, the patients’ heart rate and oxygen saturation were monitored using a pulse oximeter. The patients reported their pain levels using a VAS twenty-four hours postoperatively. Results: High levels of dental anxiety were significantly associated with higher pain scores (p = 0.000) for both groups. The hemodynamic changes during treatment remained within normal limits. The need for anesthetic reinforcement was higher in the bupivacaine group (p = 0.004). The patients in both groups reported low-intensity postoperative pain, although the pain level was slightly lower in the bupivacaine group. Conclusions: The anesthetic efficacy of articaine and bupivacaine in patients with irreversible pulpitis did not appear to be influenced by the degree of anxiety or the intake of AINEs as premedication. The intrinsic anesthetic efficacy was higher for articaine, which required less reinforcement than bupivacaine. Comparing the results obtained when performing buccal infiltration and inferior alveolar nerve block further highlighted the differences between the two anesthetics; these differences were more pronounced in the bupivacaine group, leading to rejection of the null hypothesis proposed at the beginning of the study. Full article

(1) Background: The aim of this in vitro study was to evaluate the success of indirect pulp capping (IPC) procedures over a period of 40 years. (2) Methods: The investigation of 1412 dental records included 159 patients with 366 IPC teeth having been treated from 1969 to 1980. The teeth revealed caries within the inner third of dentin, were symptom-free, and showed no pulp exposure. The caries were excavated thoroughly and teeth with accidentally exposed pulp were excluded. Zinc–oxide–eugenol was used for the IPC procedures. The posterior teeth were restored with amalgam, and the anterior teeth received direct resin composite fillings. The gathered parameters with possible influences on survival rates were age, gender, tooth locations/positions, dates of vital therapy, the number of filled surfaces, types of primary restoration material, successional treatments on each tooth, and the last dates of surveillance. Data collection and statistical analysis were performed using Excel sheets and DataTab. Significant differences among groups were computed by cox regression analysis and the significance level was set at p = 0.05. Kaplan–Meier curves were utilized to illustrate the survival rates. (3) Results: Treatment success was measured by the maintenance of vitality beyond 365 days. The loss of vitality within 365 days was determined as treatment failure. Treatment outcomes were assessed after different time periods (1 and 6 months; 1, 2, 5, 10, 20, and 40 years). Pulp vitality dropped from 95% after 3 months to 32% after 40 years. Cavity size had a significant influence on the survival of pulp, but tooth position did not; however, third molars at least initially showed a better outcome. Beyond the 1-year recall, no differences for the evaluated parameters were present. (4) Conclusions: IPC showed excellent long-term success rates, revealing a 1.7% annual failure rate after 40 years of clinical service. Larger defects suffer more pulp damage in the long run. Full article

Background and Clinical Significance: Large extensive intraoral dental swelling is uncommon in adults, and we report a rare case of large exophytic oral granulomatous tissue. A complete explanation of diagnostic steps and surgical treatments is addressed, as well as a thorough review of the literature, and a discussion of this interesting case is provided to underline the need for recognition of these vascular pyogenic proliferative lesions and discuss proper management based on the underlying cause. Case Presentation: A 21-year-old Afghan female patient who presented with an extensive intraoral pale red, friable lesion that bled easily. It was 15 × 15 mm in size related to the lower second molar, and interfered with occlusion and extended to cover the buccal and lingual surfaces of adjacent teeth. Conclusions: The presentation of this rare large reactive vascular proliferative condition of oral posterior gingiva, contribute to a better understanding and the growing body of evidence on the PG. The findings emphasize the importance of early intervention tailored to the patient’s age, lesion location, and underlying causes and patient education to prevent extensive dental tissue destruction. Full article

Objectives: A retrospective clinical audit was carried out to evaluate and compare the quality of record-keeping (QRK) and quality of root canal therapy (QRCT) performed by 4th-year and 5th-year predoctoral students. Methods: Electronic records and periapical radiographs of 702 root canal treated teeth performed by 4th-year and 5th-year predoctoral students from July 2018 to December 2021 were evaluated in compliance with standard European Society of Endodontology (ESE) and American Association of Endodontists (AAE) guidelines. Associations between the QRK and the QRCT were statistically analysed using the chi-square test (p < 0.05). Results: Overall acceptability of the QRK and the QRCT was 72.08% and 50.57%, respectively. The reference point of working length was the most common criterion not recorded (33.91%). No significant difference was observed in the QRK between 4th-year (76.05%) and 5th-year (69.70%) students (p = 0.226), as well as the QRCT between 4th-year (51.33%) and 5th-year (50.11%) students (p = 0.755). Acceptable root canal fillings were significantly higher in anterior teeth (57.48%) than in posterior teeth (47.54%) (p = 0.015). Satisfactory QRK was significantly associated with satisfactory QRCT (p = 0.046). Conclusions: Both predoctoral cohorts showed no difference in QRK and QRCT. However, QRK was better than QRCT. Comprehensive and accurate record-keeping positively impacted the QRCT. Full article

Aim: Class II Division I malocclusion poses significant challenges in orthodontics. The combination of a Herbst appliance and miniscrew anchorage emerged as a practical solution to improve skeletal and dental outcomes. This study employed finite element analysis to evaluate the biomechanical effects of a miniscrew-supported Herbst appliance on mandibular advancement and dentition movement. Methods: High-definition CBCT scans captured the maxilla and mandible’s detailed dental anatomy. The scans were stored in DICOM format for seamless integration with Mimics software (Mimics Innovation Suite research version 21.0, Materialise NV, Leuven, Belgium) for 3D reconstruction and model refinement. The appliance, designed with a maxillary fixed palatal arch and mandibular acrylic splint connected by telescoping rods, incorporated titanium TADs and elastic chains. STL models were optimized in Geomagic x Design for finite element analysis in Abaqus, assigning validated mechanical properties for materials. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Tetrahedral C3D4 elements were used for meshing, ensuring a balance between computational efficiency and detailed anatomical representation. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Dynamic simulations in CATIA evaluated mandibular movement. FEA analyzed displacement across dentoalveolar structures along the X, Y, and Z axes to assess treatment efficacy and biomechanical stability. Results: The Z displacement analysis revealed that the incisal edges of the lower central, lateral, and canines shifted lingually by 0.41, 0.4, and 0.47 mm, respectively. Additionally, the apices of the lower central, lateral, and canines displaced backwards by 0.05 mm, 0.05 mm, and 0.07 mm, respectively. Conclusions: The appliance facilitated mandibular advancement, bodily retracted the lower incisors, well-controlled the upper ones, and mesial-tipped the upper posterior teeth. In contrast with traditional functional appliances, it caused the lower anterior teeth to move backwards, while skeletal anchorage overcame some shortcomings of nonsurgical treatments. This method might be a good treatment option for growing skeletal Class II patients. Full article

Objectives: This study examines the association between a predominantly soft-textured diet and clinical signs of maxillary bone hypoplasia, such as maxillary constriction and related malocclusions like crossbite. A secondary aim is to assess whether this diet correlates with dental caries and higher plaque index in children with early mixed dentition. Methods: A total of 106 pediatric patients (4–12 years) were enrolled during routine visits (June 2022–February 2024), divided into 53 “cases” (maxillary hypoplasia and malocclusions) and 53 “controls” (normal maxillary development, no malocclusions). Patients with congenital craniofacial malformations were excluded. Dietary habits were assessed using a food questionnaire categorizing foods into four consistencies (“Semi-Liquid”, “Creamy”, “Soft”, and “Solid”). The DMFT index was calculated, considering only missing teeth due to caries. The plaque index (PI) was recorded at the first visit to evaluate the relationship between food texture and plaque accumulation. Statistical analyses included Student’s t-test, Z-test, Chi-square test, and Fisher’s exact test. Results: Mixed breastfeeding was common in both groups with no significant difference. However, natural breastfeeding was significantly more frequent in the non-crossbite group. A high-arched palate was more prevalent in the crossbite group (p = 0.042 *). Soft food consumption was significantly higher in the crossbite group compared to controls (p = 0.032 *). A statistically significant association was found between caries prevalence (DMFT > 0) and posterior crossbite (p = 0.04). Furthermore, the relationship between the dental plaque index and food consistency demonstrated a statistically significant result. In particular, there was a correlation between soft food and semi-solid foods and the plaque index (χ² = 3.55, p = 0.04). Conclusions: Posterior crossbite is associated with increased consumption of soft foods, potentially reducing the mechanical stimulation essential for maxillary growth. Conversely, non-crossbite subjects consume more hard foods and are more frequently breastfed naturally, reinforcing their role in craniofacial development. Additionally, posterior crossbite is associated with higher caries prevalence, indicating a potential connection between occlusion and oral health. Dietary texture also influences oral hygiene, with soft and semi-solid foods correlating with increased plaque accumulation, while no association was found with solid or hard foods. Full article

Background/objectives: DNA analysis is the most reliable method for the identification of human skeletal remains, especially the ones found in mass disasters or recovered from mass graves. To this aim, DNA was extracted from bones and teeth allegedly belonging to 27 Italian soldiers executed during the Second World War and exhumed from a mass grave in Ossero (Croatia). Methods: A selection of 131 different bone samples (petrous bones, femurs, metacarpal, and metatarsal bones) and 16 molar teeth were used for DNA extraction. Autosomal and Y-chromosome STR profiles were determined using a conventional CE approach, while a panel of 76 microhaplotypes was investigated through MPS. Results: Overall, 24 different autosomal consensus male profiles and six (unexpected) female profiles were identified; the male profiles were then compared with 21 alleged living relatives of the missing soldiers belonging to 14 unrelated Italian families. The DVI module of the Familias software was used for computing the LRs and the posterior probabilities (PP). The combination of autosomal STRs and microhaplotypes led to the identification of six victims and to a very likely identification of another one, supported by Y-haplotype sharing between victim and relative. Three distant victim–relative relationships resulting in low LR values for the autosomal markers showed Y-STR haplotype-sharing patterns, thus suggesting very strong support for a paternal relationship. Conclusions: The results of this study confirmed the effectiveness of the genetic approach and highlighted the presence of more individuals than expected in the mass grave, among which six were female subjects. Full article

This study delves into the fascinating morphological diversity and population groups of the Crucifix crab (Charybdis feriatus), a species steeped in the cultural and spiritual significance of recreational fisheries across East and Southeast Asia. It is known in the West as the “Crucifix crab” due to the distinct cross pattern on its shell. In this research, we collected 759 specimens from seven estuarine locations: Kyushu (Japan), Shanghai, Xiamen, Hong Kong (China), Yilan, Kaohsiung (Taiwan), and Singapore. Using advanced statistical methods, including canonical variate analysis (CVA) and hierarchical clustering, we identified three distinct population groups: the Northeast Asian group (NAG), the Kuroshio tributary group (KTG), and the Southeast Asian group (SAG). Significant morphological differences were found between these populations, suggesting that the crab’s adaptation to varying sea environments is as unique as its symbolic cross-shaped marking. The canonical variate analysis revealed that the first two eigenvalues explained 88% of the total variance (61% and 27%, respectively) in females and 80% in males (62% and 18%, respectively). The key morphometric traits CP1 (frontal teeth) and CP4 (posterior margin) showed the highest variability (correlation coefficients ranging from 0.76 to 0.82, p < 0.001). Interestingly, the traits CP1 (frontal teeth) and CP4 (posterior margin) emerged as key drivers of allometric growth variation, further enriching our understanding of this species. Full article