Search Results (1,046)

Implant-Supported Fixed Prostheses (ISFPs) have become a common option for the rehabilitation of fully edentulous arches and have traditionally incorporated metallic substructures with ceramic or acrylic veneering. The rapid expansion of CAD/CAM technologies has introduced not only a range of polymer-based materials as alternatives to conventional metallic frameworks but also the possibility of the fabrication of monolithic rehabilitations. However, the evidence regarding the mechanical behavior of monolithic polymer-based full-arch rehabilitations remains limited. This study aimed to evaluate and compare the mechanical performance of monolithic polymer-based complete prostheses under static loading using Digital Image Correlation (DIC). A total of 12 specimens (3 per group) simulating an FP3 maxillary full-arch ISFP supported by four implants were milled from four materials: poly(ether ether ketone) (G1-PEEK), poly(ether ketone ketone) (G2-PEKK), poly(methyl methacrylate) (G3-PMMA), and fiber-reinforced composite (G4-FRC). All specimens were subjected to static loading up to 200 N at the incisors region, corresponding to the anterior unsupported span, and at the occlusal surface of the molars, corresponding to the most distal portion of the cantilever, using a universal testing machine. Full-field vertical displacement and strain distributions (principal tensile, compressive, and von Mises) were acquired through a stereo DIC system and analyzed using a Linear Mixed-Effects Model with Tukey’s HSD post hoc comparisons (α = 0.05). All prostheses withstood the applied load without macroscopic failure. G3-PMMA exhibited the highest vertical displacement, exceeding 1000 µm in the anterior span and 1500 µm in the cantilever region, along with the greatest strain concentrations, particularly at the interproximal embrasures distal to the terminal abutment. G1-PEEK provided the lowest displacement in the anterior span. G4-FRC presented displacements similar to G1-PEEK and G2-PEKK at the distal cantilever, but the lowest tensile strains and the most homogeneous strain dissipation in both loading at the anterior unsupported span and distal cantilever. This indicated that the biomechanical performance of full-arch ISFPs is highly influenced by the polymer used. PEEK, PEKK, and FRC appear as promising alternatives to PMMA for monolithic full-arch rehabilitations. Full article

Apical perforation is a possible complication during root canal treatment, often caused by instrumentation beyond the working length, and requires prompt, precise sealing. In immature teeth needing endodontic therapy, the same principles used for managing apical perforations apply. Despite the widespread use of calcium silicate cement (CSC)-based materials, there is limited evidence comparing the sealing performance of putty-type CSCs and injectable bioceramic sealers in apical perforations under standardized laboratory conditions. This study aimed to compare the sealing ability of Retro-MTA cement and Endoseal MTA sealer in standardized apical perforations using the fluid-filtration method. In this in vitro study, 34 extracted human maxillary central incisors were used and divided into two groups. In Group 1, apical perforations were sealed with Retro-MTA and obturated using warm vertical compaction. In Group 2, perforations were sealed with Endoseal MTA and obturated using the single-cone technique. Micro-leakage was assessed using the fluid-filtration method. Data were analyzed with an independent t-test (α = 0.05). All samples exhibited leakage after two weeks. However, Retro-MTA demonstrated significantly lower micro-leakage than Endoseal MTA (0.265 vs. 0.473 μL/min/cmH₂O; p < 0.001), corresponding to approximately a 44% difference in leakage values between the two materials. The findings indicate that Retro-MTA provides a superior apical seal and lower leakage rates than Endoseal MTA. Therefore, Retro-MTA appears to be the more effective material for sealing apical perforations and managing open apices, potentially providing more stable apical seal under controlled laboratory conditions. Full article

Background/Objectives: Gingival phenotype is considered an important factor influencing periodontal tissue response during orthodontic treatment; however, the association between orthodontic treatment history and gingival phenotype remains unclear. This study aimed to compare gingival phenotype between orthodontically treated individuals and untreated controls and to evaluate the factors associated with gingival phenotype, including periodontal status and oral hygiene habits. Methods: This cross-sectional comparative study included 180 individuals aged 18–35 years, who were divided into two groups according to orthodontic treatment history (history of orthodontic treatment, n = 90; untreated controls, n = 90). Gingival phenotype was assessed using the transparency method at the mid-buccal aspect of the mandibular central incisor. Periodontal parameters, including Plaque Index (PI), Gingival Index (GI), probing depth (PD), and keratinized gingival width (KGW), were recorded. Oral hygiene habits and behavioral factors were also evaluated. Binary logistic regression analysis was performed to identify factors associated with gingival phenotype. Statistical significance was set at p < 0.05. Results: No significant association was found between orthodontic treatment and gingival phenotype (p > 0.05). Periodontal parameters were comparable between groups; however, orthodontically treated individuals demonstrated significantly better oral hygiene habits (p < 0.05). Logistic regression analysis revealed that male sex (OR = 6.54, p < 0.001) and increased KGW (OR = 1.668, p = 0.003) were independently associated with a thick gingival phenotype. Conclusions: The findings indicate that gingival phenotype appeared to be more strongly associated with intrinsic anatomical factors, particularly sex and KGW, rather than orthodontic treatment. It was concluded that individualized assessment of gingival phenotype and controlled orthodontic tooth movement may contribute to periodontal preservation. Full article

Background/Objectives: Class II malocclusion treatment in patients at the end of skeletal growth represents a significant clinical challenge. Traditional sequential distalization with clear aligners often requires prolonged treatment duration, carrying the risk of patient compliance burnout. This article describes a clinical technique combining a “Distalizing Bar Appliance” (DBA) with active lower clear aligners and Class II elastics for the management of dentoalveolar Class II malocclusion, and illustrates its application through a case series of three end-of-growth adolescent patients. Methods: Proposed inclusion criteria and a standardized three-phase workflow are presented: (1) distalization using a DBA supported by Class II elastics, with active lower clear aligners providing anchorage and concurrent crowding resolution; (2) alignment and arch coordination with clear aligners; and (3) finishing for occlusal settling. Results: In all three cases, a Class I molar and canine relationship was achieved, with cephalometric changes consistent with the dentoalveolar mechanisms previously reported for similar appliances and no clinically apparent mandibular skeletal changes. The concurrent use of active lower aligners allowed early crowding resolution, although careful monitoring of lower incisor and molar inclination was required to limit unwanted mesial tipping induced by Class II elastics. Conclusions: Within the limits of a case series, the technique appears clinically feasible and reproducible in carefully selected patients; comparative, controlled studies are needed before any claim of superior efficiency or effectiveness over established Class II treatment modalities can be made. Full article

Background: Dimensional stability during post-curing exposure time is critical for the clinical success of 3D-printed restorations. This study evaluates how different post-curing protocols affect the accuracy of provisional crowns. Methods: Fifty-four provisional crowns (n = 27 incisors; n = 27 premolars) were fabricated using an ASIGA 3D MAX UV printer. The crowns were subjected to three post-curing durations (5, 10, and 20 min). Dimensional deviation was quantified using RMS values. Results: RMS values showed a numerical, but not statistically significant, increase with longer post-curing times (p > 0.05). The 5 min protocol yielded the lowest descriptive deviations for both tooth types. Conclusions: Although no statistically significant differences were observed, shorter post-curing times were associated with lower RMS values and may help preserve dimensional accuracy. Further studies with larger subgroup sizes are needed to confirm these trends. Full article

Objectives: In this study, we aimed to evaluate the changes suggestive of maxillary anterior displacement in adults undergoing 3D-guided midpalatal piezocorticotomy-assisted Miniscrew-Assisted Rapid Palatal Expansion (MARPE), in addition to the contributing factors for forward maxillary movement and the subsequent immediate shift in the mandible. Methods: In this retrospective quasi-experimental study, cephalometric records of 80 adult patients (mean age 35.23 ± 8.76 years; 52 females and 28 males) were analyzed. Maxillary anterior displacement was assessed via SNA and A-Nperp(FH), while intermaxillary changes were measured using the ANB angle. Vertical and rotational changes were tracked through SN-MP, FH-MP, and various occlusal plane angles (OcP-FH, OcP-SN, OcP-GoMe). Facial height dimensions (TAFH, UAFH, LAFH, PFH) and dento-alveolar positions (U1-MP, U1LENGTH) were also recorded. Results: Following intervention, significant increases were observed in SNA (0.96°; 95% CI [0.48, 1.43]), ANB (1.42°; 95% CI [1.04, 1.80]), and A-Nperp(FH) (0.81 mm; 95% CI [0.24, 1.39]). The SN-GoMe angle increased by 0.98°, and Posterior Facial Height (PFH) decreased by 1.57 mm, while the upper incisor length (U1LENGTH) significantly decreased by 0.71 mm. Conclusions: In adults, 3D-guided midpalatal piezocorticotomy-assisted MARPE is associated with an increase in SNA, ANB, SN-GoMe, and A-Nperp(FH), and decreases in Posterior Facial Height (PFH) and the maxillary incisor length. The amount of mean midpalatal separation is moderately associated with the increase in SNA, while the increase in SNA is not associated with age or gender. Further 3D cephalometric studies would be beneficial to confirm the current findings. Full article

Prefabricated myofunctional appliances (PMAs) are designed to improve airway function by advancing the mandible, enhancing tongue posture, and reducing airway resistance, thereby facilitating nasal breathing in children with sleep-disordered breathing (SDB). This retrospective study evaluated the effects of PMAs on airway dimensions in children with skeletal Class II division 1 malocclusion. Patients were selected from a departmental database (2017–2019). The treatment group included children with Class II division 1 malocclusion, an incisor overjet of ≥6 mm, cervical vertebral maturation (CVM) stage III or earlier, and documented myofunctional dysfunction (e.g., adenoid hypertrophy, allergic rhinitis, or mouth breathing), with complete pretreatment and one-year follow-up lateral cephalometric radiographs. Patients with prior orthodontic intervention or poor compliance were excluded. A matched observation group consisted of untreated patients undergoing growth monitoring. Airway dimensions of the nasopharynx, oropharynx, and hypopharynx were measured using cephalometric radiographs, along with McNamara Airway Analysis. The total nasal symptom score (TNSS) was used as a self-report measure. A total of 34 patients (mean age 9.4 years) were included in the PMA group and 29 patients (mean age 9.6 years) in the observation group. Compared with controls, the PMA group demonstrated significant increases in nasopharyngeal (p = 0.044) and oropharyngeal (p = 0.039) airway areas, while changes in the hypopharyngeal area were not significant (p = 0.121). McNamara Airway Analysis also showed a significant improvement in upper pharyngeal airway dimensions (p = 0.018). TNSS revealed significant changes following PMA therapy (p < 0.001). These findings indicate that PMA therapy is associated with enlargement of the nasopharyngeal and oropharyngeal airway in children with skeletal Class II division 1 malocclusion, suggesting functional airway adaptation beyond simple mandibular advancement. Full article

Objectives: The present study aimed to evaluate the sexual dimorphism of skeletal and dental anomalies in Romanian orthodontic patients and to describe several important cephalometric measurements in patients with dental malocclusions. Materials and Methods: A total of 450 orthodontic records of patients older than 8 years were evaluated. On lateral cephalometric radiographs, the following cephalometric angles were digitally determined: SNA, SNB, ANB, FMA, IMPA, Max1-FH, SN-Go-Gn, N-A-Pog, Ar-Go-Me, and interincisal angle. The sagittal skeletal and dental malocclusions were diagnosed by two calibrated investigators. Results: The sample comprised 58% females, with a mean age of 20.07 (±8.63) years. The prevalence of dental malocclusions within the Romanian orthodontic sample taken into study was: 50.7% class I, 26.7% class II division 1, 13.3% class III, 4.7% class II, and class II division 2. The prevalence of skeletal anomalies within the Romanian orthodontic patient sample was: 43.3% class I, 28.7% class II due to retrognathic mandible, 17.3% class II due to prognathic maxilla, 8.7% class III due to prognathic mandible, and 2% class III due to retrognathic maxilla. Female patients presented more frequently with Class I or Class II division 2 malocclusion, whereas male patients more frequently exhibited Class III malocclusion. Female patients exhibited skeletal Class II more frequently due to retrognathic mandible, while skeletal Class III, due to prognathic mandible, was more common in male patients. Male patients were more frequently normodivergent, while female patients were more frequently hyperdivergent. Female patients exhibited retroclined upper incisors more frequently, whereas male patients exhibited proclined upper incisors more frequently. Most of the patients with class II division 1 malocclusion were females and exhibited the following cephalometric characteristics: a class II skeletal anomaly due to retrognathic mandible, normal SNA angle, decreased SNB angle, increased ANB angle, proclined upper incisors, proclined lower incisors, decreased interincisal angle, normal vertical growth pattern, closed mandibular angle, and convex facial profile. Most of the patients with class II division 2 malocclusion were females and exhibited the following cephalometric characteristics: a class II skeletal anomaly due to retrognathic mandible, normal SNA angle, decreased SNB angle, increased ANB angle, retroclined upper incisors, proclined lower incisors, increased interincisal angle, hypodivergent vertical growth pattern with a short face tendency, closed mandibular angle, and convex facial profile. Most of the patients with class III malocclusion were males and exhibited the following cephalometric characteristics: both class I and III skeletal anomaly due to prognathic mandible, normal SNA angle, increased SNB angle, decreased ANB angle, proclined upper incisors, normally inclined lower incisors, increased interincisal angle, hypodivergent, normal vertical growth pattern, and a short face tendency, normal mandibular angle, and balanced facial profile. Conclusions: The observed cephalometric differences between Class I, II and III malocclusions provide clinically relevant markers in vertical, sagittal, and dental dimensions that may provide descriptive reference data for similar orthodontic clinical samples. Full article

Background: This in vitro study aimed to evaluate the shear bond strength (SBS) of orthodontic brackets bonded using different techniques and assess whether bovine enamel demonstrates comparable behavior to human enamel in SBS testing. Methods: A total of 80 human premolars and 80 bovine mandibular incisors were randomly assigned to four bonding protocol groups according to the adhesive procedure applied: (1) adhesive only; (2) etching + adhesive; (3) etching + primer + adhesive; and (4) etching + primer + bracket base primer + adhesive. Shear bond strength (SBS) testing was performed using a universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed using two-way ANOVA and Tukey’s post hoc tests (p < 0.05). Results: Both bonding protocol and enamel substrate significantly affected SBS values (p < 0.001), whereas the interaction between these factors was not statistically significant (p = 0.061). SBS values generally increased as the bonding protocol became more complex. The adhesive-only groups demonstrated significantly lower SBS values than the other bonding protocols in both human and bovine enamel. Human enamel demonstrated significantly higher SBS values than bovine enamel overall (p < 0.001). Conclusions: Within the limitations of this in vitro study, increasing bonding protocol complexity generally resulted in higher SBS values in both human and bovine enamel. Although bovine enamel demonstrated similar overall trends across bonding procedures, significant differences between human and bovine enamel were observed. Therefore, bovine enamel should not be considered directly interchangeable with human enamel for absolute SBS measurements. Further in vivo and clinical studies are required before simplified bonding protocols can be recommended for clinical application. Full article

Objectives: The aim of the study was to assess the prevalence, severity and treatment needs of molar incisor hypomineralization (MIH) among a cohort of children in Lebanon. Methods: A cross-sectional study was performed in Akkar district in northern Lebanon on 1237 school children between 10 and 12 years old (mean age 11.11 ± 0.80 years) who were recruited from eight private schools. Clinical evaluations were performed after teeth cleaning and drying using sterile gauze. Examiners assessed all teeth present in the oral cavity using the MIH index of the EAPD. If MIH was diagnosed, a further grading was made according to the MIH-TNI index. Results: In total, 212 children (17.14% [95% CI:15.0, 19.2]) were diagnosed with MIH. Of these, 200 children with completed documentation were included in the further statistical analysis. Out of the affected cases, mild lesions were the most common at 41% (n = 82). Although males exhibited higher cumulative numbers of affected teeth (52.5%, n = 267), with notably greater proportions in moderate (17.7%) and severe (16.7%) cases, the difference between genders was not statistically significant (p = 0.069). Treatment needs increased with severity, in which mild lesions primarily required preventive care (41.0%), while moderate lesions required restorative treatments (34.0%); in contrast, severe lesions (25.0%) often necessitated extensive interventions, such as crowns, pulp therapies or even extractions. Although descriptive patterns suggested an increase in more complex treatment needs in older age groups, the association was not statistically significant (p = 0.26). Conclusions: The prevalence of MIH observed in this cohort study aligns with internationally reported values. Early detection, preventive management, and timely restorative interventions are essential to minimize the long-term impact of MIH. Full article

Background/Objectives: This study aims to compare the oral health-related quality of life (OHRQoL) of children with molar incisor hypomineralisation (MIH) and their parents with that of an age- and caries-matched control group, and to evaluate the long-term impact of dental rehabilitation on OHRQoL. Methods: A total of 30 children aged 8–12 years were included, with 15 participants in the MIH group and 15 in the control group. OHRQoL was assessed using the Pediatric Oral Health-Related Quality of Life (POQL) scale. Data were obtained at baseline and at 3, 6, and 12 months after treatment. Statistical analyses included a chi-square test, independent samples t-test, Mann–Whitney U test and Friedman test, according to data distribution. Results: Baseline POQL scores were significantly higher in the MIH group compared with the control group for both children and parents (p = 0.020 and p = 0.036, respectively). Among subscales, emotional functioning scores in children and role and physical functioning scores in parents were significantly higher in the MIH group (p = 0.027 and p = 0.032, respectively). Following dental rehabilitation, POQL scores significantly decreased in both groups (p < 0.001), and this improvement was maintained throughout the 12-month follow-up period. Conclusions: MIH has a negative impact on the OHRQoL of both children and parents, regardless of caries experience. Comprehensive dental rehabilitation results in significant and sustained improvements in OHRQoL, indicating the importance of early and comprehensive management in children with MIH. Full article

In osteopetrotic mice with homozygous inactivating mutations in the colony stimulating factor 1 (Csf1^op/op) or its receptor (Csf1r^−/−) gene, teeth fail to erupt due to severe reduction in osteoclastogenesis. Dental abnormalities have been described in the unerupted teeth of these models, but it remains unclear whether these defects arise from direct roles of CSF1R in odontogenesis or indirectly from impaired bone remodeling associated with failed eruption. Here, we examined the spatiotemporal expression of CSF1R during tooth development and inhibited CSF1R pharmacologically in utero using PLX5622 during early stages of tooth morphogenesis. Teeth and surrounding bone were analyzed at embryonic and postnatal stages using histology and high-resolution micro-computed tomography. Embryonic CSF1R inhibition resulted in reproducible abnormalities in incisor and molar morphology that were evident before and after birth and were associated with loss of normal bone remodeling at the tooth–bone interface. In contrast, postnatal CSF1R inhibition did not affect the structure or continuous growth of adult incisors. Together, these findings demonstrate a temporally restricted, indirect role for CSF1R in odontogenesis that is independent of tooth eruption and associated with remodeling of the bony crypts surrounding developing teeth by CSF1R-dependent cells. Full article

Background: The application of veneer restorations over previously composite-restored anterior teeth presents significant clinical challenges, particularly in achieving optimal marginal sealing. Aim: This in vitro study aimed to evaluate the marginal integrity and sealing ability of different 3D-printed resin veneer restorations on sound versus composite-restored anterior teeth. Materials and Methods: Eighty freshly extracted human anterior teeth (40 central incisors and 40 canines) were randomly assigned into two main groups: sound teeth and composite-restored teeth. All the teeth received 3D-printed resin veneer restoration utilizing two different types of 3D-printed resin (GC Temp Print, GC, Tokyo, Japan; and Varseosmile Triniq, BEGO GmbH & Co., Bremen, Germany). The specimens were then subjected to microleakage, marginal fitness, cement void, and cement loss testing. Results: There were no statistically significant differences among all examined groups. Microleakage scores were predominantly 0 across all groups, with median values of 0 at both cervical and proximal surfaces. Marginal fitness showed fit percentages ranging from 20% to 100%, while cement voids and cement loss were rare events (<10%). Statistical analysis confirmed no significant differences between groups (p > 0.05), with p-values ranging from 0.151 to 1.000. Conclusions: No, the presence of pre-existing composite restorations did not adversely affect 3D-printed veneer performance. The marginal integrity and sealing ability of two different 3D-printed resin veneers are not affected by the presence of previous composite restoration on cervical and proximal surfaces for both incisor and canine teeth. 3D-printed veneers applied to sound and restored teeth showed good marginal integrity and proper sealing ability. Full article

This study quantified projection-dependent geometric distortion induced by vertical camera angulation in two-dimensional (2D) dental image acquisition and evaluated its implications for integration with three-dimensional (3D) CAD/CAM and artificial intelligence (AI)-driven workflows. To our knowledge, this study is among the first to use quantitative methods to characterize projection-induced distortion across the dental arch as a function of vertical camera angulation. Fourteen fully dentate casts were photographed at nine standardized vertical angulations using a controlled acquisition setup based on the standardized occlusal plane angle (SOPA). Tooth surface areas were measured through digital tracing and analyzed with a mixed-effects model (α = 0.05). Significant associations were identified between vertical camera angulation and measured tooth surface area for all teeth except canines (p < 0.05 for all except canines). Anterior teeth demonstrated increased apparent surface area at superior camera angulations, whereas posterior teeth were more prominently represented at inferior angulations. Central incisors, lateral incisors, and first premolars exhibited maximal visibility above the occlusal plane, while second premolars and molars were more optimally visualized below it. These findings indicate that vertical camera angulation induces non-uniform, region-specific geometric distortion across the dental arch. From a computational perspective, these distortions represent a systematic source of variability in 2D photographic datasets used in CAD/CAM workflows, virtual smile design, and AI-assisted image analysis. Because modern machine learning systems depend on geometrically consistent input data, uncorrected projection-induced distortion may reduce the reliability and generalizability of downstream algorithmic outputs. Accordingly, the present findings establish a quantitative basis for recognizing projection-induced variability in 2D dental photographs and support future development of geometry-aware calibration strategies for 2D-3D digital integration. AI-assisted correction represents a future translational direction contingent upon explicit alignment between acquisition geometry, image formation, and computational modeling. Full article

Objectives: The aim of this study was to compare the diagnostic accuracy of the Diagnocat system (DGNCT LLC, Miami, Florida, USA), based on artificial intelligence algorithms, with clinical assessments performed by three dentists. Materials and Methods: The analysis was based on data obtained from cone-beam computed tomography (CBCT), focusing on the detection of carious lesions. The inclusion of three specialists with comparable levels of knowledge and professional experience increased the reliability of the results. The dentists classified teeth with carious lesions solely on the basis of CBCT imaging, physical examination, and their own clinical knowledge, under single-blind conditions, without awareness of the subsequent comparative analysis. Results: The results demonstrated a variable level of agreement between the Diagnocat system and the dentists’ assessments, depending on factors such as tooth location, as well as patient age and gender. The lowest level of agreement was observed in premolars, which may be attributed to their complex morphology. Higher diagnostic accuracy was noted in molars and incisors, particularly in younger patients. Conclusions: Further research should focus on the integration of various diagnostic modalities, including diagnostic imaging, intraoral scans, and photographic documentation, which may significantly enhance diagnostic precision, especially in cases of early-stage lesions. According to the results, the Diagnocat system demonstrates potential as a supportive tool in the diagnostic process in dental practice, as well as a screening tool enabling preliminary evaluation of imaging studies. Full article