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BMC Oral Health May 2024In this study, the antimicrobial activity of three different cleanser tablets on S. mutans and C. albicans adhesion to PMMA, polyamide and 3D printed resin was...
BACKGROUND
In this study, the antimicrobial activity of three different cleanser tablets on S. mutans and C. albicans adhesion to PMMA, polyamide and 3D printed resin was investigated.
METHODS
40 samples were prepared for PMMA (SR Triplex Hot), polyamide (Deflex) and 3D printed resin (PowerResins Denture) materials and divided into four subgroups for cleansers (Aktident™, Protefix™, Corega™ tablets and distilled water) (n = 5). After the surface preparations were completed, the samples were immersed separately in tubes containing the prepared microorganism suspension and incubated at 37˚C for 24 h. After the incubation, the samples were kept in the cleanser solutions. The samples were then transferred to sterile saline tubes. All the tubes were vortexed and 10 µl was taken from each of them. Sheep blood agar was inoculated for colony counting. The inoculated plates were incubated for 48 h for S. mutans and 24 h for C. albicans. After incubation, colonies observed on all plates were counted. Statistical analyses were done with three-way ANOVA and Tukey's multiple comparison test.
RESULTS
Polyamide material registered the highest colony count of S. mutans, whereas PMMA registered the lowest. Significant differences in S. mutans adherence (p = 0.002) were found between the three denture base materials, but no such difference in C. albicans adherence (p = 0.221) was identified between the specimens. All three cleanser tablets eliminated 98% of S. mutans from all the material groups. In all these groups, as well, the antifungal effect of Corega™ on C. albicans was significantly higher than those of the other two cleanser tablets.
CONCLUSIONS
According to the study's results, it may be better to pay attention to surface smoothness when using polyamide material to prevent microorganism retention. Cleanser tablets are clinically recommended to help maintain hygiene in removable denture users, especially Corega tablets that are more effective on C. albicans.
Topics: Candida albicans; Streptococcus mutans; Denture Bases; Denture Cleansers; Polymethyl Methacrylate; Nylons; Tablets; Colony Count, Microbial; Dental Materials; Bacterial Adhesion; Anti-Infective Agents; Materials Testing
PubMed: 38811903
DOI: 10.1186/s12903-024-04403-6 -
BMC Oral Health May 2024The aim of this study was to assess the outcomes of the combination technique of strip free gingival grafts (SFGG) and xenogeneic collagen matrix (XCM) in augmenting the... (Clinical Trial)
Clinical Trial
BACKGROUND
The aim of this study was to assess the outcomes of the combination technique of strip free gingival grafts (SFGG) and xenogeneic collagen matrix (XCM) in augmenting the width of keratinized mucosa (KMW) around dental implants, and compare its efficacy with the historical control group (FGG).
METHODS
Thirteen patients with at least one site with KMW ≤ 2 mm after implant surgery were included and received SFGG in combination with XCM. Another thirteen patients with the same inclusion and exclusion criteria from the previous trial received FGG alone. The same outcomes as the previous trial were evaluated. KMW, thickness of keratinized mucosa (KMT), gingival index (GI) and probing depth (PD) were measured at baseline, 2 and 6 months. Postoperative pain, patient satisfaction and aesthetic outcomes were also assessed.
RESULTS
At 6 months after surgery, the combination technique could attain 3.3 ± 1.6 mm of KMW. No significant change could be detected in GI or PD at 6 months compared to those at 2 months (p > 0.05). The postoperative pain and patient satisfaction in VAS were 2.6 ± 1.2 and 9.5 ± 1.2. The total score of aesthetic outcomes was 3.8 ± 1.2. In the historical FGG group, 4.6 ± 1.6 mm of KMW was reported at 6 months, and the total score of aesthetic outcomes was higher than the combination technique (4.8 ± 0.7 vs. 3.8 ± 1.2, p < 0.05).
CONCLUSIONS
The combination technique of SFGG and XCM could increase KMW and maintain peri-implant health. However, this combination technique was associated with inferior augmentation and aesthetic outcomes compared with FGG alone.
TRIAL REGISTRATION
This clinical trial was registered in the Chinese Clinical Trial Registry with registration number ChiCTR2200057670 on 15/03/2022.
Topics: Humans; Dental Implants; Female; Male; Collagen; Middle Aged; Gingiva; Adult; Patient Satisfaction; Periodontal Index; Gingivoplasty; Keratins; Esthetics, Dental; Treatment Outcome; Pain, Postoperative; Mouth Mucosa
PubMed: 38811896
DOI: 10.1186/s12903-024-04184-y -
Dental Research Journal 2024The additive manufacturing technology made the topology optimization technique feasible. This technique can indefinitely reduce the weight of the printed items with a...
BACKGROUND
The additive manufacturing technology made the topology optimization technique feasible. This technique can indefinitely reduce the weight of the printed items with a promising increase in the mechanical properties of that item.
MATERIALS AND METHODS
In the current experimental study, 50 samples were fabricated for a 3-point bending test. They were divided into ( = 5) as a control Group 1 free of internal geometries, ( = 15) for each of Groups 2-4, and they were subdivided into ( = 5) for each percentage of reduction per volume (10%, 15%, and 20%). Spherical, ovoid, and diamond shapes were each group's fundamental geometries, respectively. Cylindrical tunnels connected the voids in each group. Radiographic images were performed to validate the created geometries, the weight was measured, and flexural strength and modulus of elasticity were calculated. Data were analyzed by one-way ANOVA and Duncan's tests at < 0.05.
RESULTS
The weight results showed a significant reduction in mass. The flexural strength of Group 2 at a 10% reduction per volume had the highest mean significantly without compromising the elastic modulus. In comparison, the means of group 4 at 20% reduction showed the lowest level of toughness.
CONCLUSION
The weight was reduced according to the reduction percentage. The flexural strength of Group 2 at a 10% reduction showed the highest degree of toughness among all groups. The void shape and density influenced the mechanical properties tested.
PubMed: 38807659
DOI: No ID Found -
BMC Oral Health May 2024The aim of this in vitro study was to evaluate the changes the rheological properties of some soft lining materials, to compare the rheological properties and... (Comparative Study)
Comparative Study
PURPOSE
The aim of this in vitro study was to evaluate the changes the rheological properties of some soft lining materials, to compare the rheological properties and viscoelastic behaviour at different temperatures.
MATERIALS AND METHODS
Five soft lining materials (acrylic and silicone based) were used. the storage modulus (G'), loss modulus (G"), tan delta (tan δ) and complex viscosity (η') were chosen and for each material, measurements were repeated at 23, 33 and 37 °C, using an oscillating rheometer. All data were statistically analyzed using the Mann Whitney U test, Kruskal Wallis test and Conover's Multiple Comparison test at the significance level of 0.05.
RESULTS
Soft lining materials had different viscoelastic properties and most of the materials showed different rheological behavior at 23, 33 and 37 °C. At the end of the test (t¹5), at all the temperatures, Sofreliner Tough M had the highest storage modulus values while Visco Gel had the highest loss Tan delta values.
CONCLUSIONS
There were significant changes in the rheological parameters of all the materials. Also temperature affected the initial rheological properties, and polymerization reaction of all the materials, depending on temperature increase.
CLINICAL IMPLICATIONS
Temperature affected the initial rheological properties, and polymerization reaction of soft denture liner materials, and clinical inferences should be drawn from such studies conducted. It can be recommended to utilize viscoelastic acrylic-based temporary soft lining materials with lower storage modulus, higher tan delta value, and high viscosity in situations where pain complaint persists and tissue stress is extremely significant, provided that they are replaced often.
Topics: Rheology; Viscosity; Temperature; Materials Testing; Acrylic Resins; Elasticity; Denture Liners; Elastic Modulus; Dental Cavity Lining; Silicones; Polymerization; Humans; Oscillometry
PubMed: 38807138
DOI: 10.1186/s12903-024-04393-5 -
BMC Oral Health May 2024Retrieval of cement-retained implant-supported restorations is intriguing in cases of screw loosening. Detecting the estimated size of the screw access hole (SAH) could...
BACKGROUND
Retrieval of cement-retained implant-supported restorations is intriguing in cases of screw loosening. Detecting the estimated size of the screw access hole (SAH) could decrease destruction to the prosthesis and preserve the crown.
OBJECTIVES
To precisely localize loose implant screws through cemented crowns to reduce crown damage after screw loosening.
MATERIALS AND METHODS
In this in vitro study, 60 cement-retained implants supported 30 zirconia-based, and 30 ceramics fused to metal (CFM) lower molar crowns were invented, and each was subdivided into three subgroups (10 each). In group I (AI/BI) (control), SAH was created with the aid of orthopantomography (OPG). In contrast, in group II (zirconia-crown), SAH was created with the aid of CBCT + 3D printed surgical guide with a 2 mm metal sleeve in subgroups IIA/IIIA and CBCT + MAR was used to develop SAH in subgroups IIB/IIIB. SEM and Micro-CT scanned the SAH openings to determine the diameter of the hole, cracking, chipping, and chipping volume.
RESULTS
Regarding the effect of plane CBCT and CBCT + MAR on prepared crowns, a highly significant association between group I with group II (p = 0.001) and group III (p = 0.002) was detected. Regarding the cracking of SAH, significant differences between the zirconium crown and CFM restoration (p = 0.009) were found, while for the chipping, no significant association was seen between groups (p = 0.19).
CONCLUSIONS
CBCT, either as a plane CBCT or with MAR, significantly improved the accuracy of drilling the screw channel and decreased injury to the existing restoration and abutment, aiding in better localization of SAH in loosened implant abutment screws.
Topics: Crowns; In Vitro Techniques; Dental Prosthesis, Implant-Supported; Humans; Dental Restoration Failure; X-Ray Microtomography; Dental Cements; Cone-Beam Computed Tomography; Cementation; Zirconium; Microscopy, Electron, Scanning; Bone Screws
PubMed: 38807096
DOI: 10.1186/s12903-024-04369-5 -
Cureus May 2024Objective To evaluate and compare the stability of the open tray impression coping within the set impression while attaching the lab analog when polyether (PE) heavy...
Objective To evaluate and compare the stability of the open tray impression coping within the set impression while attaching the lab analog when polyether (PE) heavy body and polyvinyl siloxane (PVS) putty impression materials were used and the implant platform was placed sub-gingivally at three different depths. Methods Two impression materials, PE and PVS, and custom-made plexiglass models with embedded single implants to simulate implant positioning depths of 0 mm, 2 mm, and 4 mm, sub-gingivally, were used in the study. Open tray impressions were made after attaching impression coping to the implant embedded in the model. Implant lab analog was attached to the impression coping in the set impression, and its stability was measured using a universal testing machine. Forty-two open tray impressions were made in six groups, with seven impressions in each group. Descriptive statistics such as mean and standard deviation were calculated. A comparison of the mean stability between the two impression materials at each depth was done using an independent t-test. Comparison of the mean stability between the three different subgingival implant depths in each material was done by one-way ANOVA with the Scheffe multiple comparison test (post-hoc analysis). The level of significance was set at p<0.05. Results The stability of the impression coping was measured as the force in Newtons required for the displacement of the analog attached to the impression coping embedded in the set impression. PE with the embedded impression coping at a depth of 0 mm gave the highest mean stability value (4.37+/-0.41), and the least mean stability was offered by PVS with the embedded impression coping at 4 mm depth (1.88+/-0.37). When an independent t-test was done to compare the mean stability values of PE and PVS, there was a statistically significant difference at 0 mm, 2 mm, and 4 mm. On doing one-way ANOVA to compare the mean stability between the different depth groups, there was a statistically significant difference between the three depth groups in PE and PVS. Scheffe multiple comparison tests (post-hoc analysis) revealed a statistically significant difference between 0 mm, 2 mm, and 4 mm subgingival depths of the impression coping placement in both PE and PVS. Conclusion The accuracy of the master cast is an important determinant for the precise fit and long life of the final prosthesis. In the case of maxillary anterior implant placements where deep subgingival placement of the implant platform is needed for aesthetic and functional reasons, the impression material should be selected carefully to ensure the stability of the impression coping. Among the materials included in the present study, the PE impression material offered the maximum stability for impression coping compared to PVS.
PubMed: 38803409
DOI: 10.7759/cureus.61117 -
BMC Oral Health May 2024Erbium lasers safely offer the possibility of reuse for debonded restorations. Since these lasers have a high affinity for water molecules, they are absorbed by resin...
BACKGROUND
Erbium lasers safely offer the possibility of reuse for debonded restorations. Since these lasers have a high affinity for water molecules, they are absorbed by resin cement causing explosive ablation of the cement and thus, the restoration debonds. The efficiency of this process depends on many factors, including the ceramic type, its chemical composition and thickness. Therefore, this study was designed to test the time taken to debond ultrathin occlusal veneers made of three types of milled ceramic materials and evaluate the integrity of these restorations after debonding.
METHODS
Three ceramic types were evaluated in this study: lithium disilicate (IPS Emax CAD), highly condensed lithium disilicate (GC initial®LiSi), and translucent zirconia (Katana zirconia STML). Each group consisted of 8 occlusal veneers of 0.5 mm thickness. The samples were cemented to the occlusal surfaces of the upper molar teeth. An Er; Cr: YSGG laser was applied to the occlusal veneers using the scanning method, and time until debonding was calculated. The debonded samples were then inspected under a stereomicroscope for possible damage. Numerical data are presented as the mean with 95% confidence interval (CI), standard deviation (SD), minimum (min.) and maximum (max.) values. Normality and variance homogeneity assumptions were confirmed using Shapiro-Wilk's and Levene's tests, respectively. Data were normally distributed and were analyzed using one-way ANOVA followed by Tukey's post hoc test. The significance level was set at p < 0.05 for all tests. Statistical analysis was performed with R statistical analysis software version 4.3.2 for Windows (R Core Team (2023). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/).
RESULTS
There was no significant difference in debonding time between the different materials (p = 0.995). The longest debonding time was found for Katana STML (87.52 ± 20.45) (seconds), followed by Emax (86.94 ± 20.63) (seconds), while the lowest value was found for LiSi initial (86.14 ± 25.16) (seconds). In terms of damage to the debonded veneers, The Emax and zirconia samples showed no damage. However, 40% of the LiSi samples fractured during debonding, and 20% exhibited cracks. Only 40% of the LiSi samples were sound after debonding.
CONCLUSION
Er; Cr: YSGG laser can be used efficiently to remove ceramic occlusal veneers. However, its effect on LiSi restorations needs further research.
Topics: Dental Veneers; Computer-Aided Design; Ceramics; Dental Porcelain; Humans; Zirconium; Lasers, Solid-State; Dental Debonding; Materials Testing
PubMed: 38802801
DOI: 10.1186/s12903-024-04314-6 -
BMC Oral Health May 2024Dentists have a legal and ethical obligation to obtain informed consent from patients before carrying out treatment. In Uganda, the process of obtaining informed consent...
Dentists' perspectives, practices, and factors associated with informed consent process for fixed prosthodontic treatment: a cross-sectional study of kampala metropolitan area, Uganda.
BACKGROUND
Dentists have a legal and ethical obligation to obtain informed consent from patients before carrying out treatment. In Uganda, the process of obtaining informed consent in dentistry is not well documented. The aim of the present study was to determine dentists' perspectives and practices regarding informed consent to fixed prosthodontic treatment (FPT) in Kampala Metropolitan, Uganda.
METHODS
A quantitative cross-sectional study was conducted among 153 dentists from July to September 2023. Data were collected using a semi-structured self-administered questionnaire that included both closed- and open-ended questions. The questionnaire included items on participants' sociodemographic information, perspectives, and practices about informed consent for FPT. Perspectives were rated using ten items on a five-point Likert scale. The minimum possible total score was 10, and the maximum possible score was 50. Descriptive statistics and Poisson regression were used to summarize and analyze the quantitative data, and the significance level was set at p < 0.05. Open-ended items were analyzed using content analysis.
RESULTS
The majority (83.9%) of the participants were general dentists with working experience ranging from 1 to 38 years and a median of 8 years. The majority were familiar with the concept of informed consent and had positive perspectives regarding its use for FPT. The mean score for perspectives was 39.27 (SD, 5.42). However, there were variations in the practices of the dentists. More than three-quarters (87.6%) reported that they always obtained the patient's informed consent before FPT. Less than a third (29.4%) obtained written consent for FPT. About half of the dentists provided information regarding the procedure, benefits, and risks of treatment during the consent process. Bivariate analysis showed that the use of written consent for FPT was significantly (p < 0.05) associated with having a work experience of more than 10 years and having had training involving informed consent after undergraduate studies.
CONCLUSION
The present study provides baseline data regarding perspectives and practices regarding informed consent for FPT among dentists in Uganda. It is recommended that regular training courses be developed to highlight the importance of improved informed consent practices for patient protection and to instruct dentists about obtaining valid informed consent. There is a need for future research to streamline guidelines for the informed consent process in dental care in Uganda.
Topics: Humans; Uganda; Cross-Sectional Studies; Informed Consent; Male; Female; Adult; Practice Patterns, Dentists'; Surveys and Questionnaires; Dentists; Middle Aged; Attitude of Health Personnel; Denture, Partial, Fixed
PubMed: 38802781
DOI: 10.1186/s12903-024-04380-w -
Cureus Apr 2024In edentulous arches, alveolar ridge atrophy after tooth extraction is a common problem that affects patient comfort and quality of life. Implant-supported fixed...
In edentulous arches, alveolar ridge atrophy after tooth extraction is a common problem that affects patient comfort and quality of life. Implant-supported fixed restorations are a well-proven treatment option for edentulism. The concepts of implant dentistry have developed over time to produce better aesthetics and functional results. To reduce cantilever length and enable prostheses with 12 teeth, the all-on-four technique entails inserting two anterior implants axially and distally orienting two posterior implants. Compared to conventional loading, immediate loading offers various benefits without compromising quality. An instantaneous fixed provisional allows patients immediate function and preserves their quality of life while also promoting a high degree of patient satisfaction in terms of aesthetics, phonetics, mastication, and psychological comfort.
PubMed: 38800271
DOI: 10.7759/cureus.58919 -
Clinical and Experimental Dental... Jun 2024To study the feasibility of using poly methyl methacrylate (PMMA) filament and fused deposition modeling (FDM) to manufacture denture bases via the development of a...
OBJECTIVE
To study the feasibility of using poly methyl methacrylate (PMMA) filament and fused deposition modeling (FDM) to manufacture denture bases via the development of a study that considers both conventional and additive-based manufacturing techniques.
MATERIALS AND METHODS
Five sample groups were compared: heat and cold cured acrylic resins, CAD/CAM milled PMMA, 3D-printed PMMA (via FDM), and 3D-printed methacrylate resin (via stereolithography, SLA). All groups were subjected to mechanical testing (flexural strength, impact strength, and hardness), water sorption and solubility tests, a tooth bonding test, microbiological assessment, and accuracy of fit measurements. The performance of sample groups was referred to ISO 20795-1 and ISO/TS 19736. The data was analyzed using one-way ANOVA.
RESULTS
Samples manufactured using FDM performed within ISO specifications for mechanical testing, water sorption, and solubility tests. However, the FDM group failed to achieve the ISO requirements for the tooth bonding test. FDM samples presented a rough surface finish which could ultimately encourage an undesirable high level of microbial adhesion. For accuracy of fit, FDM samples showed a lower degree of accuracy than existing materials.
CONCLUSIONS
Although FDM samples were a cost-effective option and were able to be quickly manufactured in a reproducible manner, the results demonstrated that current recommended testing regimes for conventionally manufactured denture-based polymers are not directly applicable to additive-manufactured denture base polymers. Therefore, new standards should be developed to ensure the correct implementation of additive manufacturing techniques within denture-based fabrication workflow.
Topics: Denture Bases; Polymethyl Methacrylate; Printing, Three-Dimensional; Computer-Aided Design; Materials Testing; Acrylic Resins; Denture Design; Humans; Feasibility Studies; Dental Materials; Dental Bonding; Surface Properties; Stereolithography; Flexural Strength; Hardness; Solubility
PubMed: 38798134
DOI: 10.1002/cre2.880