This study aimed to compare color measurements of composite resins obtained using a spectrophotometer and a digital camera, and to evaluate the feasibility of an image-based classification model developed using Google Cloud Vertex Artificial Intelligence (AI) AutoML. Filtek Z350 XT (A2) specimens were immersed in a coffee solution at 37°C for 1, 3, or 5 hours, and CIE 1976 L*a*b* (CIELAB) color coordinates and ΔE*ab(stain) were recorded before and after immersion. Two AutoML models (VITA shade guide classification and ΔE*ab(stain) classification) were trained using standardized images. Digital photography yielded significantly lower a* values than spectrophotometry in all groups, whereas b* values did not differ significantly. Mean ΔE*ab(inter) values between instruments remained below 2.7 in all groups, indicating clinically acceptable agreement. Both AI models achieved an accuracy of 93.3%, exhibiting stable performance in identifying specimens with ΔE*ab(inter) < 2.7. Despite systematic bias in a* measurements, AI-assisted digital photography provided clinically acceptable color assessment under controlled conditions, supporting its potential as an adjunctive tool to spectrophotometric evaluation.
The purpose of this study was to evaluate the effect of zirconia surface treatment using laser surface texturing performed with a Surface Transition Machine (STM). Zirconia specimens were fabricated in two shapes: 40 cylindrical specimens and square specimens. These were divided into two groups: the sandblasting group and the STM treatment group. Each group was bonded with either resin cement (Duo-Link) or resin-modified glass ionomer (RMGI) cement (RelyX Luting 2) after Z-Prime Plus primer application. The shear bond strength was measured using a universal testing machine, and the surface characteristics were analyzed using scanning electron microscopy and high-performance 3D digital microscopy. The group bonded with resin cement after STM treatment (48.4 ± 10.4 MPa) exhibited the highest shear bond strength, whereas the group bonded with RMGI cement after sandblasting (8.1 ± 1.5 MPa) exhibited the lowest. The STM treatment group showed significantly higher shear bond strength than the sandblasted group, and the Duo-Link group demonstrated significantly higher bond strength than the RelyX Luting 2 group. Surface observations showed that the STM treatment group exhibited rough surfaces and regularly patterned retentive structures. The surface roughness (Sa) was also significantly higher in the STM treatment group (13.3 ± 1.5 μm) than in the sandblasting group (7.08 ± 0.4 μm). In conclusion, STM treatment effectively improved the shear bond strength between zirconia and cement, particularly providing the highest bond strength when used with resin cement.
Submicron polycrystalline alumina ceramic offers excellent mechanical strength and translucency, making it a promising material for pediatric crown restorations. However, due to its acid resistance and low surface energy, reliable bonding requires appropriate surface treatments and selection of compatible cement materials. This study aimed to evaluate the shear bond strength of submicron polycrystalline alumina ceramics subjected to various surface treatments and bonded with different types of luting cements. Ninety specimens were divided into three surface treatment groups: no treatment, sandblasting, and Rocatec treatment. Each group was further subdivided by cement type: glass ionomer (GI) cement (GC Fuji I), resin-modified glass ionomer (RMGI) cement (RelyX Luting 2), and self-adhesive resin cement (RelyX U200). Shear bond strength was measured using a universal testing machine, and failure modes were analyzed using scanning electron microscopy. The combination of Rocatec treatment and self-adhesive resin cement exhibited the highest bond strength. Self-adhesive resin cement demonstrated significantly higher bond strength than the other cements under all surface conditions (p < 0.017). Within the self-adhesive resin and RMGI cement groups, shear bond strength varied significantly by surface treatment (p < 0.017), while no significant difference was found in GI cement group (p > 0.017). Adhesive failures occurred only in untreated groups, whereas cohesive and mixed failures appeared exclusively in surface-treated groups. Within the limitations of this in vitro study, Rocatec treatment with self-adhesive resin cement was the most effective bonding strategy for submicron polycrystalline alumina ceramics.
This study aimed to evaluate the bonding performance of a newly developed universal adhesive, Scotchbond Universal Plus, to artificially created caries-affected dentin compared to sound dentin. Bovine teeth were used to prepare specimens with either sound dentin or caries-affected dentin, which was induced by 14 cycles of alternating demineralization and remineralization using a pH-cycling model. Forty specimens were randomly divided into four groups according to the dentin substrate condition and the type of adhesive used. The adhesives were applied according to the manufacturer’s instructions, followed by composite resin restoration. Shear bond strength was measured using a universal testing machine, and the resindentin interface was analyzed by scanning electron microscopy. The mean shear bond strength of Scotchbond Universal Plus was 37.32 ± 3.28 MPa on sound dentin and 31.21 ± 2.97 MPa on caries-affected dentin, while that of Single Bond Universal was 36.63 ± 3.93 MPa and 25.32 ± 4.67 MPa, respectively. There was no significant difference between the two adhesives on sound dentin (p = 0.621), but Scotchbond Universal Plus exhibited significantly higher bond strength than Single Bond Universal on caries-affected dentin (p = 0.008). Scanning electron microscopy and quantitative analysis revealed that Scotchbond Universal Plus produced longer and more abundant resin tags and a thinner adhesive layer compared to Single Bond Universal in caries-affected dentin. These outcomes may be attributed to the lower viscosity of the new adhesive, which facilitated improved infiltration. Within the limitations of this in vitro study, the new universal adhesive demonstrated enhanced bonding performance to caries-affected dentin and may offer clinical advantages for restorative procedures involving demineralized dentin. Further clinical investigations are necessary to validate its long-term effectiveness under natural caries conditions.
Background: Patients with autism spectrum disorder (ASD) present challenges in dental treatment cooperation owing to deficits in communication skills and social interaction. Behavioral guidance, sedation, and general anesthesia may be employed to ensure the quality of dental care for individuals with ASD. This study aimed to examine the trends in dental treatment for patients with ASD who visited the Department of Pediatric Dentistry at Dankook University Jukjeon Dental Hospital, an oral health center for the disabled in the Gyeonggi region, over the past 10 years. Methods: This study utilized the order communication system to gather data on sex, age, cooperation level, number of quadrants treated, and administration of sedation or general anesthesia for patients with ASD who visited the Department of Pediatric Dentistry at Dankook University Jukjeon Dental Hospital between January 2013 and December 2022. Results: The total number of patients with ASD increased annually, possibly due to an increase in ASD prevalence and the hospital's designation as a center for disabled oral health. General anesthesia was predominant before 2017, with a shift towards N2O-O-2 sedation. The most common age group for sedation or general anesthesia was 6-9 years, with a higher prevalence in males than in females. Notably, N2O-O-2 and midazolam sedation resulted in better cooperation and fewer treated teeth than general anesthesia. Conclusion: This study highlights the evolving trends in dental treatment for individuals with ASD, indicating a shift towards outpatient methods, particularly N2O-O-2 sedation. The sex distribution aligns with national statistics, emphasizing a higher prevalence of ASD in males than in females. These findings underscore the need for further research to establish evidence-based guidelines for optimal dental care strategies tailored to the unique needs of individuals with ASD.
A novel water-soluble root canal filling material based on sodium iodide (NaI) has been developed to overcome the limitations of existing iodine-based formulations. However, the biological stability of this approach in animal studies remains unverified. This study evaluated the biocompatibility of NaI compared to commercial root canal filling materials (Calcipex II and Vitapex®) in pulpectomized canine teeth to assess its clinical applicability. Following a four-week observation period, none of the experimental groups exhibited tooth mobility or fistula formation. Radiographic and micro-CT analyses revealed no radiolucency in periapical lesions. Histopathologic evaluation demonstrated the absence of inflammatory responses in periapical regions across all material groups, with histological inflammation scoring 0. High-magnification histological examination of periapical areas showed well-preserved periodontal ligament tissue in all groups. Despite certain limitations of NaI-based fillings in the pulp cavity, including loss of radiopacity and tooth discoloration, NaI demonstrates potential as a safe and effective alternative for pulp filling material, particularly due to its minimal risk of root resorption and inflammatory response.
Premature loss of root canal-treated primary teeth has long been a concern in dentistry. To address this, researchers developed a sodium iodide-based root canal-filling material as an alternative to traditional iodoform-based materials. The goal of this study was to improve the physicochemical properties of the sodium iodide-based material to meet clinical use standards. To resolve high solubility issues in the initial formulation, researchers adjusted component ratios and added new ingredients, resulting in a new paste called L5. This study compared L5 with L0 (identical composition minus lanolin) and Vitapex as controls, conducting physicochemical and antibacterial tests. Results showed that L5 met all ISO 6876 standards, demonstrated easier injection and irrigation properties than Vitapex, and exhibited comparable antibacterial efficacy to Vitapex, which is currently used clinically. The researchers conclude that if biological stability is further verified, L5 could potentially be presented as a new option for root canal-filling materials in primary teeth.
This study aimed to enhance the physicochemical properties of sodium iodide-based root filling materials, particularly solubility. In earlier developmental stages, the iodoformcontaining paste exhibited high antibacterial efficacy but failed to meet only the solubility requirement among the ISO 6876 criteria. Therefore, this study focused on enhancing the physicochemical properties of the paste under development, particularly centering on reducing its solubility. Four experimental groups were established, including three control group. The previously developed D30 paste was named the Oil 33 group, and the control group was named the Vitapex® group. The Oil 50 group, in which the oil content was increased, and the Oil 45L group, in which lanolin was incorporated. The physical properties (solubility, pH, flowability, and film thickness) of the four pastes were evaluated according to the ISO 6876 standards. No significant differences were observed between the Oil 45L and Vitapex® groups in any of the physical property evaluations. While the Oil 33 and Oil 50 groups met the ISO 6876 standards for flowability and film thickness, the Oil 45L group met all the physical properties. However, reducing the overall oil content may be necessary to enhance the antimicrobial properties. The result of the physicochemical experiments showed that the Oil 45L group with the newly formulated composition and incorporated lanolin exhibited low solubility meeting the ISO 6876 standard of ≤ 3%. We were able to develop a paste with more stable solubility than previous iodide-based root-filling materials. Therefore, the oil content must be further adjusted to improve its antimicrobial properties. If other physical properties also meet the ISO 6876 standards and demonstrate excellent results in cytotoxicity tests, this root filling material could potentially replace existing options.
This study aimed to compare color matching between single-shade composite resin-restored teeth with various pulp capping materials and the dentin surrounding the restoration through instrumental analysis and visual evaluation of the color difference. Fifty maxillary right central incisor acrylic resin teeth were prepared with standardized Class III cavities on the proximal surfaces. These teeth were divided into five groups: restored with single-shade composite resin only; Ultra-Blend™ plus followed by single-shade composite resin; TheraCal PT™ followed by single-shade composite resin; Endocem® MTA premixed followed by single-shade composite resin; and Well-root PT™ followed by single-shade composite resin. The color difference (ΔEab*) between the restored area and the center of the resin teeth was measured using a spectrophotometer. No significant color difference was observed in groups restored with only single-shade composite resin, Ultra-Blend™ plus, and TheraCal PT™. The visual evaluation revealed that Ultra-Blend™ plus exhibited the best color matching score, whereas the Endocem® MTA premixed and Well-root PT™ groups showed significantly lower color matching scores than the single-shade composite resin-only group. When opting for single-shade composite resin usage for anterior tooth restorations with the aim of reducing chair time, pulp capping materials UltraBlend™ plus and TheraCal PT™ provide esthetically pleasing results.
This study compared the solubility, water absorption, dimensional stability, release of various ions (hydroxyl, calcium, sulfur, strontium, and silicon), and cytotoxicity of lightcured resin-modified pulp-capping materials. Resin-modified calcium hydroxide (Ultrablend™ plus, UBP), light-cured resin-modified calcium silicate (TheraCal LC™, TLC), and dual-cure resin-modified calcium silicate (TheraCal PT™, TPT) were used. Each material was polymerized; solubility, 24-hour water absorption, and 30- day dimensional stability experiments were conducted to test its physical properties. Solubility was assessed according to the ISO 6876 standard, and 24 hours of water absorption, 30 days of dimensional stability were assessed by referring to the previous protocol respectively. Eluates at 3 and 24 hours and on 7, 14, and 28 days were analyzed according to the ISO 10993-12 standard. And the pH, Ion-releasing ability, cell proliferation rate, and cell viability were assessed using the eluates to evaluate biochemical characteristics. pH was measured with a pH meter and Ion-releasing ability was assessed using inductively coupled plasma atomic emission spectrometry (ICP-AES). Cell proliferation rate and cell viability were assessed using human dental pulp cells (hDPCs). The former was assessed by an absorbance assay using the CCK-8 solution, and the latter was assessed by Live and Dead staining. TPT exhibited lower solubility and water absorption than TLC. UBP and TPT demonstrated higher stability than TLC. The release of sulfur, strontium, calcium, and hydroxyl ions was higher for TLC and TPT than for UBP. The 28-day release of hydroxyl and silicon ions was similar for TLC and TPT. TLC alone exhibited a lower cell proliferation rate compared to the control group at a dilution ratio of 1 : 2 in cell proliferation and dead cells from Live and Dead assay evaluation. Thus, when using light-cure resin-modified pulp-capping materials, calcium silicate-based materials can be considered alternatives to calcium hydroxide-based materials. Moreover, when comparing physical and biochemical properties, TPT could be prioritized over TLC as the first choice.
This study aimed to compare the color stability and surface roughness of three-dimensional (3D) printing resin according to polishing methods. 3D-printed resin specimens were fabricated at TC-80DP (Graphy, Seoul, Korea) with a stereolithography 3D printer, and the specimens were divided into three groups, each of which was not polished, was polished using Enhance®, and was polished using a Sof-LexTM disc. The CIE L*a*b* value and the surface roughness of each group were measured and immersed in artificial saliva and orange juice after 0, 1, 7, 30, and 60 days, and the color difference (ΔE*) was calculated. As a result of the study, no noticeable color change was observed in artificial saliva, but a noticeable color change was demonstrated in orange juice after 60 days of immersion, and the difference was significant. In the Sof-LexTM group, surface roughness according to the solution was found to be significantly higher in the orange juice than that in artificial saliva. No significant difference in color change was found according to the polishing method, but surface roughness was significantly lower in the Sof-LexTM group than both that of the unpolished group and that of the Enhance® group. Nevertheless, all groups exhibited clinically acceptable properties regardless of their higher surface roughness than the threshold for plaque accumulation. Overall, this study recommends utilizing Sof-LexTM for polishing 3D printing resin when used in primary anterior tooth coverage.
This study aimed to compare the physical properties of 4 kinds of calcium silicatebased cements (CSCs): 2 kinds of powder-liquid mix type (RetroMTA® [RTMX] and Endocem® MTA Zr [EZMX]) and 2 kinds of premixed type (Well-Root™PT [WRPR] and Endocem® MTA premixed [ECPR]) CSCs, respectively. Further, we assessed the setting times, solubility values, and compressive strengths of the cements. The shortest setting time was observed for EZMX (123.33 ± 5.77 seconds), followed by RTMX (146.67 ± 5.77 seconds), ECPR (260.00 ± 17.32 seconds), and WRPR (460.00 ± 17.32 seconds), respectively. The highest solubility was observed for WRPR (9.01 ± 0.55%), followed by RTMX (2.17 ± 0.07%), EZMX (0.55 ± 0.03%), and ECPR (0.17 ± 0.03%). Furthermore, the highest compressive strength was observed for ECPR (76.67 ± 25.67 Mpa), followed by WRPR (38.39 ± 7.25 Mpa), RTMX (35.07 ± 5.34 Mpa), and EZMX (4.07 ± 0.60 Mpa). In conclusion, the premixed type CSCs (WRPR and ECPR) exhibited longer setting times compared to the powder-liquid mix type CSCs (EZMX and RTMX). The solubility test showed that ECPR had the lowest solubility while WRPR had the highest solubility, with a statistically significant difference between them (p < 0.0083). Additionally, the compressive strength test showed that ECPR had the highest compressive strength, while EZMX had the lowest compressive strength, also with a statistically significant difference between them (p < 0.0083). ECPR is a promising material as it is premixed, eliminating the need for mixing time, and it has also demonstrated improved solubility and compressive strength, making it a potentially favorable option for clinical use.
Calcium silicate-based cement (CSC) is a pharmaceutical agent that is widely used in dentistry. This bioactive material is used for vital pulp treatment due to its excellent biocompatibility, sealing ability, and antibacterial activity. Its drawbacks include a long setting time and poor maneuverability. Hence, the clinical properties of CSC have recently been improved to decrease its setting time. Despite the widespread clinical usage of CSC, there is no research comparing recently developed CSCs. Therefore, the purpose of this study is to compare the physicochemical, biological, and antibacterial properties of four commercial CSCs: two powder–liquid mix types (RetroMTA® [RETM]; Endocem® MTA Zr [ECZR]) and two premixed types (Well-Root™ PT [WRPT]; Endocem® MTA premixed [ECPR]). Each sample was prepared using circular Teflon molds, and tests were conducted after 24 h of setting. The premixed CSCs exhibited a more uniform and less rough surface, higher flowability, and lower film thickness than the powder–liquid mix CSCs. In the pH test, all CSCs showed values between 11.5 and 12.5. In the biological test, cells exposed to ECZR at a concentration of 25% showed greater cell viability, but none of the samples showed a significant difference at low concentration (p > 0.05). Alkaline phosphatase staining revealed that cells exposed to ECZR underwent more odontoblast differentiation than the cells exposed to the other materials; however, no significant difference was observed at a concentration of 12.5% (p > 0.05). In the antibacterial test, the premixed CSCs showed better results than the powder–liquid mix CSCs, and ECPR yielded the best results, followed by WRPT. In conclusion, the premixed CSCs showed improved physical properties, and of the premixed types, ECPR exhibited the highest antibacterial properties. For biological properties, none of these materials showed significant differences at 12.5% dilution. Therefore, ECPR may be a promising material with high antibacterial activity among the four CSCs, but further investigation is needed for clinical situations.
Background: Anxiety and fear in children's dental care are major impediments to successful dental care. High -quality dental treatment can be achieved using various behavioral control methods; however, conscious sedation using drugs can be used if behavioral control is difficult, owing to excessive fear and anxiety. This study aimed to examine the trends in conscious sedation implemented in pediatric dentistry at the Dankook University Dental Hospital over the past 11 years. Methods: This study included 6,438 cases of dental treatment under conscious sedation conducted over 11 years between January 2011 and December 2021 in the Department of Pediatric Dentistry at Dankook University Dental Hospital. Results: Over the past 11 years, the number of dental treatments under sedation has increased. In the case of inhalation sedation using nitrous oxide, the rate of increase was approximately twice every year, and the use of midazolam gradually decreased. The average age of children who underwent sedation was 5.11 years, and the rate of sedation treatment in children aged <4 years tended to decrease, while that of children aged >5 years tended to increase. This is related to the trend of changes in drugs used. In a sex -based survey, sedation treatment rate was higher in males than that in females. Conclusion: Appropriate selection of sedatives can reduce the frequency of general anesthesia and minimize complications through efficient and safe dental treatments. Trend analysis of sedation by year will help provide guidelines for the appropriate selection of sedation for dental treatment of children and patients with disability.
Objectives:The purpose of this study was to compare the fracture strength and traslucency of 3D printing resin crowns according to different thicknesses.Methods: Resin crowns were designed with CAD software and a 3D scanner, using scanned data of the #61 tooth model.Resin Crowns with different thicknesses were printed using a 3D printer, and subsequently divided into four groups according to thickness (0.3, 0.5, 0.7, and 1.0 mm).Fracture strength was compared among groups with a resin strip crown of 1.0 mm thickness.Compressive force was applied using a universal testing machine at 30° along the lingual surface at 1 mm/min cross head speed.For translucency evaluation, thin square specimens were printed of thicknesses 0.3, 0.5, 0.7, and 1.0 mm, and translucency was measured using a spectrophotometer.Results: As a result of fracture strength measurement, fracture strength increased as thickness increased, and a significant difference was observed solely between thicknesses of 0.3 and 0.5 mm, and the thicknesses of 0.3 and 0.5 mm (P<0.05).Translucency decreased as thickness increased, and similarly, a significant difference was observed only between thicknesses of 0.3 and 0.5 mm and the thicknesses of 0.7 and 1.0 mm (P<0.05).Conclusions: A 3D printing resin crown can be used as a clinical option for restoring a primary anterior tooth affected by caries.
Objectives: This study aimed to compare the physical properties and antibacterial effectiveness of iodoform based root filling pastes, Vitapex® and Metapex®, with sodium iodide root filling paste (NaI paste) for primary teeth. Materials and Methods: The physical properties (flowability, film thickness, radiopacity) of the pastes were evaluated according to ISO 6876:2012. The antibacterial activity against Enterococcus faecalis strain (ATCC 6538) was evaluated using a direct contact test. Results: There was no significant statistical difference (p > 0.05) observed in the flow and film thickness of NaI paste when compared to the currently available root canal filling materials. The average flow capacities for Vitapex®, Metapex®, and NaI paste were 15.40 mm, 21.25 mm, and 20.01 mm, respectively. The average film thickness for Vitapex®, Metapex®, and NaI paste were 33.3 μl, 22.6 μl, and 25.0 μl, respectively. However, NaI paste showed lower radiopacity than the existing materials, and this difference was statistically significant (p < 0.05) NaI paste demonstrated higher antimicrobial activity than the available materials, and this difference was also statistically significant (p < 0.05). Conclusion: Compared to the existing commercialized root canal filling materials, NaI paste exhibited similar performance in terms of flow and film thickness, and superior antimicrobial activity against E. faecalis . Hence, NaI paste could be a promising root filling material for primary teeth and may be a potential alternative to existing materials.
The aim of this study was to retrospectively analyze the effects of pulp treatment on exfoliation of primary teeth and its related factors. In this study, 167 teeth of 97 patients aged 6 months to 12 years who were treated with pulp treatment at Dankook Dental Hospital were selected, and information related to pulp treatment and tooth loss was collected. The included subjects were 72 primary anterior teeth (43.1%) and 95 primary posterior teeth (56.9%), of which 56 were males (57.7%) and 41 females (42.3%). The mean follow-up period was 106.1 ± 38.7 months, and the mean age at pulp treatment was 34.8 ± 15.4 months for primary anterior teeth and 69.1 ± 25.1 months for primary posterior teeth. Unilaterally pulpectomized teeth were significantly exfoliated earlier than the same tooth on the opposite side (p < 0.05). Also, in the case of teeth with periapical lesions, despite pulp treatment, the probability of extraction due to infection has been increased on primary anterior teeth (p < 0.05), but not on posterior teeth (p > 0.05). Pulpectomized teeth were lost earlier, an average of 7.8 months for primary anterior teeth and 8.5 months for primary posterior teeth. Early loss of the primary tooth can lead to space loss and premature eruption of the successor, so this can be considered when planning or performing treatment of the primary tooth.