Search Results (15)

Optical diagnostic techniques represent an attractive complement to conventional pulp vitality tests, as they can provide direct information about the vascular status of the pulp. However, the complex, multi-layered structure of a tooth significantly influences the detected signal and, ultimately, the diagnostic decision. Despite this, the impact of the various dental components on light propagation within the tooth, particularly in the context of diagnostic applications, remains insufficiently studied. To help bridge this gap and potentially enhance diagnostic accuracy, this study employs digital optical twins based on the Monte Carlo method. Using incisor and molar models as examples, the influence of tooth and pulp geometry, blood concentration, and pulp composition, such as the possible presence of pus, on spectrally resolved transmission signals is demonstrated. Furthermore, it is shown that gingival blood absorption can significantly overlay the pulpal measurement signal, posing a substantial risk of misdiagnosis. Strategies such as shifting the illumination and detection axes, as well as time-gated detection, are explored as potential approaches to suppress interfering signals, particularly those originating from the gingiva. Full article

This study aims to analyze the precision and amount of dental tissue removed during overlay preparation by experienced and less experienced operators, with and without magnification systems. Methods: Sixty-four first upper molar Frasaco Typodonts were divided into four groups: experienced operators with magnification (Group 3, EXP+LOU), experienced operators without magnification (Group 1, EXP), dental students with magnification (Group 4, STU+LOU), and dental students without magnification (Group 2, STU). Preparations including an occlusal reduction of 1.5 mm and an interproximal box of 1 mm width. The prepared teeth were scanned and analyzed using reverse engineering software (Geomagic Control X, Oqton, San Francisco, CA, USA) to evaluate preparation accuracy, dental substance removal, and comparison to a control unprepared tooth. Results: The analysis showed that the average reduction was 32.19%. Group 4 (STU+LOU) showed significantly improved accuracy with magnification compared to Group 2 (STU). Group 3 (EXP+LOU) achieved the best result with an average reduction of 23.96%, while Group 2 (STU) had the worst result with 41.28%. Conclusions: Conservative indirect restorations, such as overlays, effectively preserve dental tissue. Operator experience and magnification systems are crucial for preparation accuracy. Magnification improves precision for less experienced operators, reducing tooth volume loss by 9.1%, and enhances cavity design accuracy, ensuring a better restoration fit and minimizing the marginal gap. Full article

In contemporary dental practice, clinicians have a variety of materials and options for restoring single teeth compromised by carious or non-carious diseases. According to studies and new concepts in biomimetic restorative dentistry, indirect ceramic restorations will play an increasingly important role in daily practice. We follow up and evaluate clinically three times over a 10-year period on eighty-six indirect restorations (n = 86) of lithium disilicate e.Max Press (Ivoclar, Schaan, Liechtenstein) in 32 patients. Restorations are evaluated in the 2nd, 5th, and 10th years after the fixation. Four of the restorations studied (n = 86) had to be replaced at year 5 follow-up because of fracture (failure rate: 4.65%; Kaplan–Maier). There are no restorations with bulky, cohesive fractures. Lithium disilicate ceramic restorations provide a good treatment alternative for a 5- to 10-year period of observation, and they can be successfully applied in dental practice in 91.73% to 98.84% of cases. Advancements in digital dentistry, including the use of intraoral scanners and CAD/CAM technology, are set to further refine the precision and efficiency of indirect restorations for distal teeth, enabling quicker turnaround times and improved fit. Additionally, ongoing developments in biomaterials promise to enhance the durability and biocompatibility of these restorations, potentially leading to better long-term success rates and patient satisfaction. The goal of this clinical study was to look at how well biomimetic ceramic overlays and onlays made of lithium disilicate held onto teeth with a IV-generation adhesive system for 10 years. The study also looked at how well the edges of the teeth adjusted and how strong the teeth were overall. Full article

Objective: Familial isolated hypoparathyroidism is a rare genetic disorder due to no or low production of the parathyroid hormone, disturbing calcium and phosphate regulation. The resulting hypocalcemia may lead to dental abnormalities, such as enamel hypoplasia. The aim of this paper was to describe the full-mouth rehabilitation of a 15-year-old girl with chronic hypocalcemia due to a rare congenital hypoparathyroidism. Clinical considerations: In this patient, in the young adult dentition, conservative care was preferred. Onlays or stainless-steel crowns were performed on the posterior teeth, and direct or indirect (overlays and veneerlays) were performed on the maxillary premolars, canines, and incisors, using a digital wax-up. The mandibular incisors were bleached. The treatment clearly improved the patient’s oral quality of life, with fewer sensitivities, better chewing, and aesthetic satisfaction. The difficulties were the regular monitoring and the limited compliance of the patient. Conclusion: Despite no clinical feedback in the literature, generalized hypomineralized/hypoplastic teeth due to hypoparathyroidism in a young patient can be treated as amelogenesis imperfecta (generalized enamel defects) with a conservative approach for medium-term satisfactory results. Highlights: This study provides new insights into the management of enamel hypoplasia caused by familial isolated hypoparathyroidism, helping to improve patient outcomes in similar cases. Full article

The microbiota in the oral cavity has a strict connection to its host. Its imbalance may determine oral diseases and can also have an impact on the systemic health. Probiotic strains may help in the restoration of a balanced condition. For this purpose, we screened the antibacterial and antiadhesive activities of many viable probiotic strains (Lactobacillus acidophilus PBS066, Lactobacillus crispatus LCR030, Lactobacillus gasseri LG050, Lactiplantibacillus plantarum PBS067, Limosilactobacillus reuteri PBS072, Lacticaseibacillus rhamnosus LRH020, Bifidobacterium animalis subsp. lactis BL050, Lacticaseibacillus paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114) against two main oral pathogens, Streptococcus mutans and Aggregatibacter actinomycetemcomitans, involved in dental caries and periodontal disease development and progression. Considering both the agar overlay preventive and treatment models, seven probiotics determined greater inhibition zones against the tested pathogens. This behavior was further analyzed by the plate count method and scanning electron microscope imaging. L. plantarum PBS067, L. rhamnosus LRH020, L. paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114 prevent the growth and adhesion of oral pathogens in a strain-specific manner (p < 0.0001). These probiotics might be considered as an alternative effective adjuvant to improve oral and systemic well-being for future personalized treatments. Full article

Dental ceramics are susceptible to slow, progressive crack growth after cyclic loading. The purpose of this study was to investigate the progressive patterns of cracks in two different types of CAD/CAM ceramic materials used with three different partial posterior indirect restoration (PPIR) designs and to determine the materials’ failure risk using a fatigue test. Standard initial cracks were formed in Standard Tessellation Language (STL) files prepared for three different PPIRs. The materials chosen were monolithic lithium disilicate (LS) and polymer-infiltrated ceramic networks (PICNs). The extended finite element method (XFEM) was applied, and the fatigue performance was examined by applying a 600 N axial load. The cracks propagated the most in onlay restorations, where the highest displacement was observed. In contrast, the most successful results were observed in overlay restorations. Overlay restorations also showed better fatigue performance. LS materials exhibited more successful results than PICN materials. LS materials, which can be used in PPIRs, yield better results compared to PICN materials. While inlay restorations demonstrated relatively successful results, overlay and onlay restorations can be specified as the most and the least successful PPIR types, respectively. Full article

Spatial accessibility to health services influences service utilisation and eventually impacts the disease burden. This cross-sectional study analysed the spatial accessibility of schoolchildren to public oral health facilities and school dental services (SDS) and vice versa in Selangor. Overlay and proximity analysis from geo-mapping software was employed to map the primary dental clinics with SDS, the public schools, and the proximity between primary dental clinics with SDS and public schools by travelling distance (5 km, 10 km, 20 km) and travelling time (15 min, 30 min). Over half of the schoolchildren in Selangor are within 5 km of accessibility to primary dental clinics and SDS teams. Meanwhile, nearly half of the primary and secondary schools, particularly in rural areas, are located within a more than 5 km service area of public oral health facilities. The SDS teams have a travel burden of more than 20 km to the public schools in Selangor’s northern and north-western districts of large geographical areas. Simultaneously, most public primary and secondary schools are within 15 min of driving time from primary dental clinics. Geo-mapping highlights the inequalities in spatial accessibility to public oral health facilities with SDS among schoolchildren in Selangor. It is time to prioritise the resources, SDS, and preventive programmes to reduce inequalities in oral health accessibility among schoolchildren in Selangor. Full article

Dental implants are a reliable alternative to treating edentulism. In clinical situations where the dentition has been severely affected by partial edentulism, advanced wear, or periodontal disease, establishing important occlusal elements such as the occlusal plane, incisal guidance, and esthetics can be hard to visualize at the diagnostic stage. Contemporary data-acquisition technologies such as 3D scanners and CAD/CAM systems permit the precise manufacture of highly complex devices applicable to any stage of restorative treatment. The present clinical report presents an alternative technique for evaluating the projected artificial tooth relationships, vertical dimension, and occlusal plane in patients with severely weakened dentition by using a 3D-printed overlay template. Full article

This study aimed to assess marginal bone loss and complication rates of mandibular overdentures retained on two implants with conventional and immediate loading protocols. Twenty edentulous patients were treated with mandibular two-implant-retained overdentures and new complete maxillary dentures. In one half of the sample, the implants were loaded immediately by VulkanLoc^® abutments. In the counterpart group, these abutments were connected to the implants two months after implant placement (conventional protocol). Treatment outcomes were evaluated at 2, 6, and 12 months after implant placement. According to the pre- and post-insertion radiographs, there was a mean marginal bone loss of 0.25–0.59 mm (CI 95%) after 13.4 ± 2.1 months of follow-up. There were no significant differences between groups. The failure rate (percentage of implants failing per year) was slightly higher in the conventional loading group (14.0 ± 32.7%) than in the immediate loading group (8.3 ± 18.0%). The findings of the present study suggested that there were no differences in marginal bone loss observed at one year for immediately loaded implants (0.40–0.39 mm) versus conventionally loaded implants (0.44- 0.36 mm) placed for the retention of mandibular overdentures. There were no differences in primary and secondary stability of immediately loaded versus conventional implants; however, in the conventional loading group, stability increased significantly between implant placement compared at both 6 and 12 months post-placement. Full article

Several viewpoints have been reported regarding the effect of temporary cements, different surface pretreatment protocols before adhesive cementation, and predictive factors. This in vitro study tested if temporary cement, pretreatment of the tooth surface, the size of enamel or dentine influence adhesive cementation to zirconia ceramics. Twenty premolars were prepared for determination of enamel and dentin area, bond strength test and failure analysis. The samples were divided into two groups: untreated prior adhesive cementation (n = 10) and with temporary cementation done, pretreated prior adhesive cementation (n = 10). Zirconia overlays (Katana Zirconia STML) were cemented on the grounded flat teeth surfaces using Panavia V5. An additional six premolars underwent dentine tubule analysis with SEM to detect temporary cement residues after temporary cementation on an untreated tooth surface (n = 3) and on a pretreated surface (n = 3). The independent sample t-test was used to compare the two groups and the means of the total tooth, dentin or enamel areas did not differ significantly between the untreated and pretreated specimens. The mean tensile bond strength was significantly (p = 0.005) higher in the pretreated specimens (337N) than in the untreated ones (204N). The overall multivariable linear regression model with three predictors (surface pre-treatment, enamel area and dentine area) was significant (p = 0.003), among which the size of enamel was the strongest predictor (β = 0.506; p = 0.049), followed by the pretreatment effect (β = 0.478; p = 0.001) and the size of dentin area (β = −0.105; p = 0.022). Full article

Background: As artificial intelligence (AI) becomes increasingly important in modern dentistry, we aimed to assess patients’ perspectives on AI in dentistry specifically for radiographic caries detection and the impact of AI-based diagnosis on patients’ trust. Methods: Validated questionnaires with Likert-scale batteries (1: “strongly disagree” to 5: “strongly agree”) were used to query participants’ experiences with dental radiographs and their knowledge/attitudes towards AI as well as to assess how AI-based communication of a diagnosis impacted their trust, belief, and understanding. Analyses of variance and ordinal logistic regression (OLR) were used (p < 0.05). Results: Patients were convinced that “AI is useful” (mean Likert ± standard deviation 4.2 ± 0.8) and did not fear AI in general (2.2 ± 1.0) nor in dentistry (1.6 ± 0.8). Age, education, and employment status were significantly associated with patients’ attitudes towards AI for dental diagnostics. When shown a radiograph with a caries lesion highlighted by an arrow, patients recognized the lesion significantly less often than when using AI-generated coloured overlays highlighting the lesion (p < 0.0005). AI-based communication did not significantly affect patients’ trust in dentists’ diagnosis (p = 0.44; OLR). Conclusions: Patients showed a positive attitude towards AI in dentistry. AI-supported diagnostics may assist communicating radiographic findings by increasing patients’ ability to recognize caries lesions on dental radiographs. Full article

The purpose of this study was to evaluate clinical performance, survival, and complications of indirect composite inlays, onlays, and overlays on posterior teeth. Digital records of 282 patients treated between 2014 and 2018 were accessed and analyzed retrospectively. The included patients received 469 composite restorations luted with seven different resin-based types of cement, i.e., Filtek Ultimate Flow, Enamel Plus, Relyx Ultimate, Harvard Premium Flow, Relyx Unicem, Filtek Bulk Fill Flowable, and Filtek Ultimate. The restorations had been clinically and radiographically evaluated annually. The mechanical and clinical complications, e.g., debonding, fracture, and secondary caries, were evaluated and recorded. The examined restorations exhibited a high survival rate (84.9%), and failure was found in only 71 cases. Fracture was the most common cause (n = 36), followed by prosthetic work release (n = 19) and secondary caries (n = 16). There was a statistically significant difference between failure and cement material (Sig. < 0.001); the composite-based cements (87.2%) had a high survival rate compared to the resin-based cement (72.7%). Similarly, the cements with high viscosity (90.2%) had significantly higher survival rates than the low-viscosity cements (78.9%). Moreover, onlays showed higher longevity compared to overlays (Sig. = 0.007), and patients aged under 55 years showed less complications (Sig. = 0.036). Indirect composite restoration was a successful solution to tooth structure loss. The material of the cementation is an important part of the success. Higher survival rate was found in our study when the fixation materials with high viscosity were used, thus suggesting using these materials with indirect restorations. Composite-based cements had significantly higher survival rate than resin-based cements. Full article

Dental fluorosis is a common disorder caused by excessive fluoride intake during tooth development. The esthetic consequences of dental fluorosis can negatively affect oral health-related quality of life and have lasting psychosocial effects. In severe cases, where the fluorosed enamel is prone to chipping, flaking, and developing caries, minimally invasive procedures are ineffectual and a more substantial restorative approach is required to restore optimal function and esthetics. However, no definitive guidelines exist for the management and treatment of severe dental fluorosis due to the limited evidence available in the literature. This case report describes the full-mouth rehabilitation of a patient with severe dental fluorosis utilizing adhesively bonded all-ceramic crowns, veneers, and overlays. The successful follow-up on this case indicates that adhesively bonded restorations may provide a viable option in the functional and esthetic management of severely fluorosed dentition. Full article

The aim of this study was to compare the accuracy of implant placement by using the conventional freehand method, the surgical guide alone, the dental navigation system alone, and the dental navigation system with a surgical guide. The participants were aged 20 years or older and were requiring dental implant surgery according to an assessment made by a dentist between July 2014 and December 2017. A total of 128 dental implants were inserted, 32 dental implants in each group, and participants with similar or identical age (i.e., 20–50 years or 50 years or above) and missing tooth locations were paired for comparison. Accuracy was measured by overlaying the real position in the postoperative Cone Beam Computerized Tomography (CBCT) on the virtual presurgical placement of the implant in a CBCT image. Using the dental navigation system with a surgical guide could help dentists to position implants more accurately. Total, longitudinal, and angular error deviation were significantly different (p < 0.0001). The same level of accuracy could be obtained for the different jaws and tooth positions. The one-way analysis of variance (ANOVA) showed that the total, longitudinal, and angular errors differed significantly (p < 0.0001). A comparison of the four dental implant surgical methods indicated that the combination of a dental implant navigation system and a surgical guide kit achieved the highest accuracy in terms of the different tooth positions and jaws. Full article

There is an increasing body of evidence establishing the advantages of dual-energy CT (DECT) for evaluation of head and neck squamous cell carcinoma (HNSCC). Focusing on a single-source DECT system with fast kVp switching, we will review the principles behind DECT and associated post-processing steps that make this technology especially suitable for HNSCC evaluation and staging. The article will review current applications of DECT for evaluation of HNSCC including use of different reconstructions to improve tumor conspicuity, tumor-normal soft tissue interface, accuracy of invasion of critical structures such as thyroid cartilage, and reduce dental artifact. We will provide a practical approach for DECT implementation into routine clinical use and a multi-parametric approach for scan interpretation based on the experience at our institution. The article will conclude with a brief overview of potential future applications of the technique. Full article