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The European Journal of Prosthodontics... May 2024To evaluate the effect of different agitation methods on apical extrusion of 1.5% sodium hypochlorite (NaOCl) in an ex vivo model of immature teeth.
OBJECTIVE
To evaluate the effect of different agitation methods on apical extrusion of 1.5% sodium hypochlorite (NaOCl) in an ex vivo model of immature teeth.
METHODS
Sixty extracted human inferior incisors were prepared to simulate immature teeth and embedded in an artificial root socket made of silicone impression material. The teeth were then divided into four groups: Conventional needle irrigation (CNI) alone, CNI supplemented with Ultrasonic Irrigant Activation (UIA), EasyClean (EC), or XP-endo Finisher (XPF). Extruded NaOCl was collected, reacted with m-cresol purple, and its absorbance values were measured. The data were statistically analyzed using One-way analysis of variance with a significance level of 5%.
RESULTS
All groups showed apically extruded irrigating solution, and the mean volumes of extruded NaOCl did not differ significantly between any of the test groups (p⟩0.05).
CONCLUSION
The activation of 1.5% NaOCL by UIA, EC, or XPF as supplementary to CNI does not promote greater apical extrusion when compared to CNI alone in simulated immature teeth.
Topics: Sodium Hypochlorite; Humans; Root Canal Irrigants; Therapeutic Irrigation; Spectrophotometry; Root Canal Preparation; Tooth Apex; In Vitro Techniques; Incisor
PubMed: 38536738
DOI: 10.1922/EJPRD_2635Vieira07 -
Biomimetics (Basel, Switzerland) Mar 2024The popular immediate dentin sealing (IDS) technique is used to improve the bond strength of indirect restorations. This systematic review assessed whether bond strength... (Review)
Review
The popular immediate dentin sealing (IDS) technique is used to improve the bond strength of indirect restorations. This systematic review assessed whether bond strength is affected by the type of aging conditions, bonding agents, flowable resin composites, impression materials, temporary materials, and/or resin cement used within the IDS procedure. A comprehensive database search of PubMed, Embase, Scopus, Ovid Medline, Web of Sciences, Cochrane Library, Dentistry & Oral Sciences Source, and ProQuest was carried out up to 30 January 2024 without publication year or language limitations. Only in vitro full-texts regarding the effect of IDS on bond strength were included, and the quality of their methods was assessed via a Risk of Bias (RoB) test. In total, 1023 pertinent studies were initially found, and 60 articles were selected for review after screening for the title, abstract, and full texts. IDS application improves the bond strength of indirect restorations to dentin and reduces the negative effects of temporary materials on the bond durability of final indirect restorations. Filled dentin bonding agents or combinations with flowable resin composite are preferred to protect the IDS layer from conditioning procedures.
PubMed: 38534867
DOI: 10.3390/biomimetics9030182 -
Journal of Esthetic and Restorative... Mar 2024The aim of this study was to compare the accuracy of full-arch conventional implant impressions using two different materials (A-silicone and polyether) to full-arch...
AIM
The aim of this study was to compare the accuracy of full-arch conventional implant impressions using two different materials (A-silicone and polyether) to full-arch digital implant impressions produced from two intraoral scanning devices.
MATERIALS AND METHODS
A master model was fabricated representing an edentulous mandible with four implants with internal connection placed at the sites of canines and first molars. The anterior implants were parallel to the residual ridge, while the two posterior implants had an angulation of 15° to the distal and 15° to the lingual respectively. The conventional technique was performed with open-tray of non-splinted impression copings. Two different impression materials were used, A-silicone and polyether at monophase medium body consistencies. The digital impressions were obtained with the use of two different intraoral scanners, after the connection of scan bodies. A total of 10 impressions were produced for each of the four experimental groups. The conventional models as well as the master model were digitized using a high-resolution laboratory scanner. The STL files of the models and of the intraoral impressions were imported in a powerful superimposition software, for the conduction of measurements in pairs of files. The software calculated the 3D deviations, as well as the linear and angular displacements among scan bodies at the digital files. For "trueness" measurements every STL file of each experimental group was superimposed to the digital master model, while for "precision" measurements all STL files of each experimental group were superimposed to each other.
RESULTS AND CONCLUSIONS
The accuracy of full arch mandibular implant impressions was influenced both by the impression technique used (conventional vs. digital) and the impression material used (A-silicone vs. polyether) or the intraoral scanner used (Trios vs. Heron). In terms of "trueness," A-silicone showed the highest impression accuracy with the lowest deviation values, followed by polyether and Trios, but the differences between the three groups were in the majority not statistically significant. Heron showed statistically lower accuracy results in all measurements compared to the other groups. In terms of "precision", conventional impressions with the use of A-Silicone or polyether were statistically significantly superior to digital impressions with either scanner. A-Silicone and polyether showed no statistically significant difference between them.
PubMed: 38534043
DOI: 10.1111/jerd.13227 -
Cureus Feb 2024Background The disinfection of dental impression materials is a cornerstone of infection control in dental practice. This study aimed to evaluate the effectiveness of...
Background The disinfection of dental impression materials is a cornerstone of infection control in dental practice. This study aimed to evaluate the effectiveness of two disinfectants, sodium hypochlorite and iodophor, on alginate and silicone impression materials, which are prone to microbial contamination. Methods The study was structured into two main groups based on the impression material: Group I (alginate) and Group II (addition silicone), each further subdivided into two subgroups for disinfection with sodium hypochlorite and iodophor. For each subgroup, initial microbial swabs were taken before any treatment, followed by a second swab after rinsing and a final swab after disinfection. The mean colony-forming unit (CFU) counts, standard deviations, and standard errors of the mean were calculated for each stage of treatment. Results Prior to disinfection, Group I had a mean CFU count of 2,529.40, while Group II had a lower mean CFU of 1,417.40. After rinsing, there was a significant decrease in CFUs in both groups, with Group I at 1,337.10 and Group II at 415.10. Post-disinfection, Group I showed a mean CFU count of 73.00 for sodium hypochlorite and 0.00 for iodophor. Similarly, Group II achieved a CFU reduction of 99.00 with sodium hypochlorite and 0.00 with iodophor, demonstrating a marked reduction in microbial presence. Conclusion Iodophor was exceptionally effective in disinfecting both alginate and silicone impression materials, eliminating all detectable CFUs. Sodium hypochlorite also significantly reduced microbial counts but was not as effective as iodophor. Rinsing prior to disinfection was instrumental in reducing the microbial load, underscoring its importance in the disinfection protocol.
PubMed: 38533142
DOI: 10.7759/cureus.54846 -
BMC Oral Health Mar 2024To compare the crown accuracy and time efficiency of a complete digital workflow, utilizing an auxiliary occlusal device and IO scanning, with a conventional workflow,... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
To compare the crown accuracy and time efficiency of a complete digital workflow, utilizing an auxiliary occlusal device and IO scanning, with a conventional workflow, for multiple implant-supported single crowns.
MATERIALS AND METHODS
24 patients with two adjacent posterior implants were included. 12 patients were randomly assigned to digital workflow group, involving intra-oral scanning with an auxiliary occlusal device and manufacture of customized abutments and zirconia single crowns (test group). The other 12 were assigned to the conventional workflow (control group), involving conventional impression and CAD-CAM crowns based on stone casts. Crown scanning was done before and after clinical adjustment using an intraoral scanner. Two 3D digital models were overlapped to assess dimension changes. Chair-side and laboratory times for the entire workflow were recorded and a linear mixed model and Independent-sample t tests were used for the statistical analysis.
RESULTS
The maximum occlusal deviation was 279.67 ± 112.17 μm and 479.59 ± 203.63 μm in the test and control group, respectively (p < 0.001). The sizes of the occlusion adjustment areas were 12.12 ± 10.51 mm and 25.12 ± 14.14 mm in the test and control groups, respectively (p = 0.013). The mean laboratory time was 46.08 ± 5.45 and 105.92 ± 6.10 min in the test and control groups, respectively (p < 0.001).The proximal contact adjustment and mean chair-side time showed no statistically significant difference between two groups.
CONCLUSIONS
A digital workflow for two implants-supported single crowns using an auxiliary device required fewer occlusal crown adjustments, and less laboratory time compared to conventional workflow.
CLINICAL RELEVANCE
The use of auxiliary occlusal devices in IOS enhances the accuracy of virtual maxillomandibular relationship in extended edentulous spans. Consequently, employing a digital workflow for multiple implants-supported crowns using IO scanning and an auxiliary occlusal device proves to be a feasible, accurate and efficient approach.
Topics: Humans; Workflow; Dental Prosthesis Design; Dental Implants; Crowns; Computer-Aided Design
PubMed: 38519905
DOI: 10.1186/s12903-024-03986-4 -
Clinical Implant Dentistry and Related... Mar 2024The present study aimed to systematically review the studies comparing the accuracy of intraoral scan (IOS) and conventional implant impressions (CI) in completely... (Review)
Review
OBJECTIVES
The present study aimed to systematically review the studies comparing the accuracy of intraoral scan (IOS) and conventional implant impressions (CI) in completely edentulous patients.
MATERIALS AND METHODS
Electronic searches were performed in PubMed, Embase and Cochrane CENTRAL up to December 1, 2023. Clinical studies and in vitro studies reporting the accuracy of digital full arch impressions were included. The primary outcome is the 3-dimensional deviations between the study reference models. A risk of bias assessment was performed for clinical studies. A stratified meta-analysis and a single-armed meta-analysis were conducted.
RESULTS
A total of 49 studies were included, with 8 clinical studies and 41 in vitro studies. For comparison between IOS and conventional impressions, studies were categorized into two groups based on the different measurement methods employed: RMS and CMM. In studies using RMS, the result favored the IOS in the unparalleled situation with the mean difference of -99.29 μm (95% CI: [-141.38, -57.19], I = 81%), while the result was opposite with the mean difference of 13.62 μm (95% CI: [10.97, 16.28], I = 26%) when implants were paralleled. For different brands of IOS, the accuracy ranged from 76.11 μm (95% CI: [42.36, 109.86]) to 158.63 μm (95% CI: [-14.68, 331.93]).
CONCLUSIONS
Accuracy of intraoral scan is clinically acceptable in edentulous arches, especially for unparalleled implants. More clinical studies are needed to verify the present finding.
PubMed: 38517307
DOI: 10.1111/cid.13321 -
Journal of Prosthodontics : Official... Mar 2024The aims of the present study were (a) to compare the scanning time and image count to complete optical scans of a typodont between augmented-reality-assisted intraoral...
PURPOSE
The aims of the present study were (a) to compare the scanning time and image count to complete optical scans of a typodont between augmented-reality-assisted intraoral scanning (ARIOS) and intraoral scanning (IOS); (b) to compare the accuracy of the digital casts derived from ARIOS and IOS; (c) to compare participant-related outcomes between ARIOS and IOS.
MATERIALS AND METHODS
A multi-session within-subject experiment was conducted to compare ARIOS and IOS. Thirty-one dental students participated in the study. Following a trial session, each participant obtained optical scans under ARIOS and IOS conditions. The time required to complete the scan, and the number of images taken were recorded. Participant feedback was collected using entry, exit, and NASA-Task Load Index (TLX) surveys. The accuracy of the digital casts derived from the optical scans was measured in root mean square error (RMSE).
RESULTS
The present study found a 6.8% increase in preference for ARIOS from entry to exit survey. Slightly more participants favored the ARIOS setup compared to IOS; 54.8% of participants favored ARIOS, 9.7% were indifferent, and 35.5% favored IOS. NASA-TLX subscale ratings were higher for IOS in general apart from mental demand. The accuracy of the digital casts between ARIOS and IOS was comparable in RMSE.
CONCLUSION
ARIOS was advantageous compared to IOS in ergonomics, improved scanner tracking, and ease of scanner orientation. However additional trials, increased field of view, and better superimposition of scanning status to the target site were improvements desired by the study participants.
PubMed: 38507280
DOI: 10.1111/jopr.13836 -
Journal of Periodontal Research Jun 2024The purpose of this study is to investigate regenerative process by immunohistochemical analysis and evaluate periodontal tissue regeneration following a topical...
OBJECTIVE
The purpose of this study is to investigate regenerative process by immunohistochemical analysis and evaluate periodontal tissue regeneration following a topical application of BDNF to inflamed 3-wall intra-bony defects.
BACKGROUND
Brain-derived neurotrophic factor (BDNF) plays a role in the survival and differentiation of central and peripheral neurons. BDNF can regulate the functions of non-neural cells, osteoblasts, periodontal ligament cells, endothelial cells, as well as neural cells. Our previous study showed that a topical application of BDNF enhances periodontal tissue regeneration in experimental periodontal defects of dog and that BDNF stimulates the expression of bone (cementum)-related proteins and proliferation of human periodontal ligament cells.
METHODS
Six weeks after extraction of mandibular first and third premolars, 3-wall intra-bony defects were created in mandibular second and fourth premolars of beagle dogs. Impression material was placed in all of the artificial defects to induce inflammation. Two weeks after the first operation, BDNF (25 and 50 μg/mL) immersed into atelocollagen sponge was applied to the defects. As a control, only atelocollagen sponge immersed in saline was applied. Two and four weeks after the BDNF application, morphometric analysis was performed. Localizations of osteopontin (OPN) and proliferating cell nuclear antigen (PCNA)-positive cells were evaluated by immunohistochemical analysis.
RESULTS
Two weeks after application of BDNF, periodontal tissue was partially regenerated. Immunohistochemical analyses revealed that cells on the denuded root surface were positive with OPN and PCNA. PCNA-positive cells were also detected in the soft connective tissue of regenerating periodontal tissue. Four weeks after application of BDNF, the periodontal defects were regenerated with cementum, periodontal ligament, and alveolar bone. Along the root surface, abundant OPN-positive cells were observed. Morphometric analyses revealed that percentage of new cementum length and percentage of new bone area of experimental groups were higher than control group and dose-dependently increased.
CONCLUSION
These findings suggest that BDNF could induce cementum regeneration in early regenerative phase by stimulating proliferation of periodontal ligament cells and differentiation into periodontal tissue cells, resulting in enhancement of periodontal tissue regeneration in inflamed 3-wall intra-bony defects.
Topics: Animals; Brain-Derived Neurotrophic Factor; Dogs; Cementogenesis; Alveolar Bone Loss; Proliferating Cell Nuclear Antigen; Osteopontin; Periodontal Ligament; Male; Guided Tissue Regeneration, Periodontal; Bone Regeneration; Dental Cementum; Periodontium; Mandible; Cell Proliferation
PubMed: 38501357
DOI: 10.1111/jre.13244 -
Heliyon Mar 2024The aim of this study is to investigate the effect of the aging process on the marginal fit and fracture resistance of temporary crowns prepared using different...
AIM
The aim of this study is to investigate the effect of the aging process on the marginal fit and fracture resistance of temporary crowns prepared using different materials.
MATERIALS AND METHOD
The steel die to represent the maxillary first premolar used in this study was produced on a CNC turning machine to include an anatomical occlusal surface. A total of 160 epoxy resin dies were obtained by taking impressions with conventional impression methods on the metal die. Epoxy resin dies were randomly divided into four groups. Temporary crowns were prepared for each group from poly acrylic resin (Vita CADTemp®), bis-acryl composite resin (Protemp 4), poly methyl methacrylate (PMMA; Imident) and poly ethyl methacrylate (PEMA; Dentalon Plus) restorative materials. Half of the specimens (n = 20) in each group (n = 40) were randomly separated and the aging process was applied 5000 times in the device. Marginal gap measurements on epoxy resin dies were made using a stereomicroscope. The fracture strength test of the specimens was performed by using the Instron Universal Test Device. Jamovi 2.2.5 statistical program was used for statistical analysis.
RESULTS
When compared to temporary crowns prepared from all other materials, poly acrylic resin (Vita CADTemp ®) temporary crowns observed significantly lower marginal gap values (59,05 μm) regardless of the aging process, and a significantly higher fracture resistance (478,44 N) in the presence of aging process (p < .05 for each). While the highest marginal gap value was detected in PMMA (Imident) (120.36 μm) temporary crowns with aging process, the lowest marginal gap value was observed in poly acrylic resin (Vita CADTemp®) (59.05 μm) crowns without non-aging process. The marginal fit and fracture resistance of all temporary crowns were negatively affected by the aging process.
CONCLUSION
Our findings revealed the superiority of poly acrylic resin (Vita CADTemp®) crowns to the temporary crowns prepared from all other materials in terms of the significantly lower marginal gap in the absence of aging process, and the significantly higher fracture resistance in the presence of aging process. Marginal fit and fracture resistance values for all materials were found to be within clinically acceptable limits.
PubMed: 38500976
DOI: 10.1016/j.heliyon.2024.e26737 -
Medical Science Monitor : International... Mar 2024BACKGROUND The advent of digital impressions using computer-aided design and manufacturing technology (CAD/CAM) has simplified and improved the fabrication of implant...
BACKGROUND The advent of digital impressions using computer-aided design and manufacturing technology (CAD/CAM) has simplified and improved the fabrication of implant prostheses in dentistry. The conventional impression has several drawbacks, including tray selection, material type, impression technique, impression disinfection, and cast model storage. The inaccuracies caused by distortion and contraction of impression material can be minimized with digital impressions. This study aimed to compare digital dental impressions of 10 working casts made using the Pindex laser removable die system to fabricate parallel drill channels vs 10 working casts made using the Di-Lok plastic tray removable die system. MATERIAL AND METHODS An implant master die with 2 dental implant analogs was fabricated. Ten working casts using the Pindex laser removable die system with parallel drill channels and 10 working casts using the Di-Lok plastic tray removable die system were fabricated. The working casts were scanned using an extra-oral laboratory scanner and the implant master model was scanned with an intra-oral scanner. RESULTS The properties of the casts made using the 2 systems were evaluated and analyzed with ANOVA and post hoc Tukey test. The mean horizontal linear distances between A1B1 (P<0.021), A2B2 (P<0.018), C1D1 (P<0.026), C2D2 (P<0.03), B1C1 (P<0.01), and mean vertical distances between B1A2 (P<0.015), C1D2 (P<0.001), B1B2 (P<0.028), and C1C2 (P<0.001) were significantly different between the Pindex system and Di-Lok tray system as compared to intra-oral scans. CONCLUSIONS Complete digital workflow with intra-oral scans were more than the partial digital workflow with extra-oral scans for the Pindex system and Di-Lok tray systems.
Topics: Workflow; Models, Dental; Computer-Aided Design; Denture, Partial, Fixed; Research Design; Dental Implants
PubMed: 38500254
DOI: 10.12659/MSM.943706