Search

Objective: This study evaluated the effect of incorporating 1 wt% egg shell powder (ESP) into Biodentine™ (BD) on its physicomechanical properties. Methods: Chicken eggs were ground and sterilized. Then, one wt% ESP was added to BD powder and mixed with BD liquid. The mixture's pH and solubility were measured on 1, 3, 7, and 28 days. The setting time was determined using a Gillmore needle. Compressive strength was measured using a universal testing machine after 1 and 14 days. Surface chemistry was analyzed via FTIR spectroscopy. The findings were compared by independent samples t-test, the repeated measures ANOVA, and the Bonferroni post-hoc test (a = 0.05). Results: pH levels were comparable between the groups (P > 0.05). BD-ESP had a higher setting time than BD (P < 0.001). BD-ESP solubility was significantly higher than BD on day 1 (P = 0.001) but lower on days 7 (P = 0.006) and 28 (P = 0.001). On day 1, BD had higher compressive strength than BD-ESP (P = 0.027), whereas the compressive strength of both groups was comparable on day 14 (P = 0.099). FTIR analysis revealed an additional IR band associated with the phosphate band in the BD-ESP group, suggesting new apatite formation. Conclusions: Incorporating 1% ESP into BD resulted in lower initial solubility but higher solubility after a week and a month, likely due to increased ion dissolution. ESP incorporation also promoted additional apatite formation but negatively impacted the setting time and initial strength of BD. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the calcium ion (Ca2+) release from apical plugs formed by three different bioceramic cements in simulated immature teeth with open apices. Methods: In this in-vitro study, 66 single-rooted lower premolar teeth were divided into three groups, each containing 22 samples, as follows: Group A: ProRoot MTA, Group B: Bio-C Repair, and Group C: Dia-Root Bio MTA. Each sample was prepared to simulate immature teeth with open apices. A 4 mm apical plug was inserted at the open apex area. Calcium ion release was measured on the 7th, 15th, and 30th days using an atomic absorption spectrophotometer. Data were analyzed using Kruskal-Wallis, and Mann-Whitney U tests at the significance level of P < 0.05. Results: The apical plugs formed by different groups showed significant differences in Ca2+ release over 30 days (P<0.001). Group C had the highest release on days 7 (18.08 ± 0.57 ppm) and 15 (16.39 ± 0.75 ppm), whereas Group B showed the lowest levels (P < 0.05). On day 30, Group A had the highest Ca2+ release (2.36 ± 0.25 ppm), which was significantly greater than that of Groups B and C (P < 0.05). Conclusions: Dia-Root Bio MTA showed the highest calcium ion release on days 7 and 15, whereas ProRoot MTA exhibited the most significant release on day 30. Both Dia-Root Bio MTA and ProRoot MTA are more favorable options than Bio-C Repair for root repair in immature, non-vital teeth. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the calcium ion (Ca2+) release from apical plugs formed by three different bioceramic cements in simulated immature teeth with open apices.Methods: In this in-vitro study, 66 single-rooted lower premolar teeth were divided into three groups, each containing 22 samples, as follows: Group A: ProRoot MTA, Group B: Bio-C Repair, and Group C: Dia-Root Bio MTA. Each sample was prepared to simulate immature teeth with open apices. A 4 mm apical plug was inserted at the open apex area. Calcium ion release was measured on the 7th, 15th, and 30th days using an atomic absorption spectrophotometer. Data were analyzed using Kruskal–Wallis, and Mann-Whitney U tests at the significance level of P < 0.05.Results: The apical plugs formed by different groups showed significant differences in Ca2+ release over 30 days (P

Objective: This study evaluated the effect of incorporating 1 wt% egg shell powder (ESP) into Biodentine™ (BD) on its physicomechanical properties.Methods: Chicken eggs were ground and sterilized. Then, one wt% ESP was added to BD powder and mixed with BD liquid. The mixture’s pH and solubility were measured on 1, 3, 7, and 28 days. The setting time was determined using a Gillmore needle. Compressive strength was measured using a universal testing machine after 1 and 14 days. Surface chemistry was analyzed via FTIR spectroscopy. The findings were compared by independent samples t-test, the repeated measures ANOVA, and the Bonferroni post-hoc test (α = 0.05).Results: pH levels were comparable between the groups (P > 0.05). BD-ESP had a higher setting time than BD (P < 0.001). BD-ESP solubility was significantly higher than BD on day 1 (P = 0.001) but lower on days 7 (P = 0.006) and 28 (P = 0.001). On day 1, BD had higher compressive strength than BD-ESP (P = 0.027), whereas the compressive strength of both groups was comparable on day 14 (P = 0.099). FTIR analysis revealed an additional IR band associated with the phosphate band in the BD-ESP group, suggesting new apatite formation.Conclusions: Incorporating 1% ESP into BD resulted in lower initial solubility but higher solubility after a week and a month, likely due to increased ion dissolution. ESP incorporation also promoted additional apatite formation but negatively impacted the setting time and initial strength of BD.

Purpose: The aim of this study was to investigate the dentin shear bond strength (SBS) and bonding interface of three recently developed "universal" resin luting cements based on different modalities. Methods: The dentin SBS and interfacial analysis of three recently launched "universal" resin luting cements, namely, G-Cem One, RelyX Universal and Panavia SA cement universal, were studied. All bonding protocols, including the previous use of their dedicated primer or universal adhesive in touch-cure mode or light-cure mode were performed. Variolink Esthetic LC used in conjunction with Scotchbond Universal Plus was used as a control group. For each group (n = 9), 10 specimens were tested for dentin SBS and two were examined by scanning electron microscopy. SBS were analyzed by two-way ANOVA followed by Dunnett's test. Results: SBS values showed that the three "universal" resin luting cements tested exhibit different adhesive behaviors. G-Cem One with its touch-cure activated primer had a greater SBS to dentin (25.5 MPa) than that of the control group (22.1 MPa). Conclusion: "Universal" resin luting cements have variable efficacy when used in self-curing mode. The touch-curing mode is also of concern but may show high potential for some formulations. [ABSTRACT FROM AUTHOR]

Dental implant restorations attached to cement can potentially result in peri-implant mucositis and peri-implantitis if cement residues are present. Effectively predicting and eliminating such dental cement residues is crucial for preventing complications. This study focuses on creating a regression model using the pixel values to predict the Excess Cement Residues (ECR) by employing an octagonal surface imaging approach. A model featuring gingival imitation, ten abutments, and ten crowns was created, and the cemented implants underwent thorough photographic and analytical assessment. The ECR was determined through two distinct approaches: the Computerized Planimetric Method (CPM) and the weighing method. Across ten implants in this in vitro study, ECR varied from 0.3 to 21 mg, with an average of 5.69 mg. The findings reveal a higher amount of ECR on the distal, mesiobuccal, and mesial sides. Utilizing Pearson's correlation, a coefficient value of r = 0.786 signifies a strong correlation between CPM and the weighing method. The regression model further aids in predicting ECR based on pixel values. The octagonal surface imaging approach not only vividly captures information about ECR in the implant cementation region but also emphasizes the feasibility of ImageJ as an effective tool for detecting ECR. The congruence between CPM and the weighing method results supports the application of the regression model for precise ECR prediction. [ABSTRACT FROM AUTHOR]

To compare retention strength of the polymethylmethacrylate (PMMA) crown and surfacepretreated PEEK abutment using various dental cements. Fifty PEEK abutments (PW plus Co., Ltd, Nakhon Pathom, Thailand) were pretreated with 90% sulfuric acid 60 seconds then cemented with milled Polymethylmethacrylate (PMMA) crown using various dental cements (Temp-Bond NE, Zinc phosphate, Panavia F2.0, RelyX U200 and Superbond C&B). After stored in 37ºC distilled water for 24 hours, the specimens were submitted to crown pull-off test using universal testing machine at crosshead speed 0.5 mm/minute. The retention strength (MPa) was calculated, and failure modes were recorded. All test groups were significantly different (p<0.05). Panavia F 2.0 presented the highest retention strength, followed by Temp-Bond NE. Zinc phosphate cement showed the lowest retention strength (p < 0.05). Superbond C&B and RelyX U200 could not acquire retention strength due to detachment of the abutment. Resin cement exhibited superior retention for PMMA crown and surface-pretreated PEEK abutment compared to Temp-Bond NE and Zinc phosphate cement. [ABSTRACT FROM AUTHOR]

Introduction: The dentist's level of knowledge and abilities is one of the determining factors in the correct selection and application of dental cements. This study aimed to investigate the level of knowledge, attitude, and practice of general dentists and specialists about the application of different dental cements. Methods: This descriptive-analytical study was cross-sectional one which conducted on 150 specialist and general dentists in governmental and private centers in Kurdistan province (2019) who performed fixed prosthetic treatments, was done through census and available sampling. The data collection tool was a questionnaire. To analyze data, T-test and ANOVA tests were used in SPSS-22 software. A significance level was considered less than 0.05. Ethical considerations: This study was conducted after the approval of the protocol in the research ethics committee and receiving the ethical code number IR.MUK.REC.1398.302 and according to the Declaration of Helsinki. Results: The overall average score of dentists' knowledge was 6.5, which was close to and higher than the average scores and had a significant relationship with the grade and place of employment (P<0.05). The overall average score of attitude was 3.4, which was almost equal to the average scores. There was a significant relationship between grade and gender with attitude score (P<0.05). The overall average score of the dentists' practice was 5, which was higher than the average scores, and the practice score had a significant relationship with gender, place of employment, and grade (P<0.05). Conclusions: The average score of knowledge, attitude, and practice of dentists was average, and in general, the scores of specialists were higher than general dentists. Women had a higher attitude and practice score. People working in the private sector had a higher knowledge score. To increase the knowledge, attitude, and practice of general dentists, there is a need to hold training courses. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the influence of resin cement material types on tooth with endocrown and onlay restorations. The first molar was scanned using Micro‐CT and underwent a modelling process to obtain the 3D model for computational simulation. Eight models were simulated in the current study with two loading conditions (720N vertical load and 200N oblique load), two types of restoration (onlay and endocrown restorations), and two resin cement variants (dual‐cure resin cement and light‐cure resin cement). The tooth with onlay restoration showed a significant stress reduction (up to 70%) when using light‐cure resin cement compared to dual‐cure resin cement. In contrast, types of cement did not affect stress distribution in the tooth with endocrown restoration. The current study found that dual‐cure resin cement was preferable in Endocrown and Onlay restorations, due to dual‐cure resin cement provided better bond strength compared to light‐cure resin cement. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of Casein Phosphopeptide-Amorphous Calcium Phosphate (ACP) containing bonding agents on dentin shear bond strength and remineralization potential. Material and Methods: This in vitro study evaluated 45 extracted human premolars. The teeth were decoronated, and the tooth crown was split into buccal and lingual halves. The specimens were then flat-grounded by a 180-grit abrasive. The specimens were then randomized into three groups (n=15). Adper Scotchbond Multi-Purpose (SBMP) primer and adhesive were used for bonding in the control group. ACP in 10wt% and 20wt% concentrations was added to SBMP adhesive and used in groups 2 and 3, respectively. After the application of primer and adhesive and light-curing them for 10 s, a transparent silicon cylinder was placed on a dentin surface and cured for 10 s; then, the cylinder was filled with composite resin and was cured for the 40s from each side. The specimens underwent 3000 thermal cycles, and a universal testing machine measured the SBS. To assess the remineralization quality, a total of 6 dentin samples (2 specimens for group) were prepared and underwent X-ray diffraction, attenuated total reflection Fourier-transform infrared spectroscopy, and scanning electron microscopy-energy dispersive X-ray analysis. One-way analysis of variance was used to analyze the data. The level of p0.05) — the addition of ACP to SBMP adhesive enhanced dentin remineralization. Increasing the ACP concentration from 10% to 20% increased the formation of hydroxyapatite. Conclusion:Adding amorphous calcium phosphate confers remineralizing property to SBMP adhesive without compromising its shear bond strength to dentin.

Purpose: To validate the rationale of using a conventional light-curing resin-based composite (RBC) to lute thick indirect restorations by measuring mini-interfacial fracture toughness (mini-iFT). Materials and Methods: Freshly exposed dentin of extracted third molars (n = 64) was immediately sealed with a thin layer of an experimental RBC with a 50 wt% or 75 wt% (IDS) filler load. Two- or 6-mm-thick CAD/CAM composite blocks were luted onto IDS using either pre-heated light-cure or dual-cure luting RBC, with the latter having served as control. Samples were cut into sticks, upon which a notch was prepared at the interface between IDS and luting RBC, prior to being submitted to a 4-point bending test to determine mini-iFT. The results were analyzed using a mixed linear model (LME). Failure mode at the fractured interface was determined using scanning electron microscopy (SEM). Results: LME revealed that mini-iFT was not significantly affected by the composite block thickness (p = 0.39), but by the luting RBC (p < 0.0001) and the IDS RBC filler load (p = 0.0011). Mini-iFT was higher with 50 wt% fillerloaded RBC IDS and when luted using the light-curing RBC. Conclusion: This work provides the proof of concept that 2- and 6-mm-thick indirect restorations can safely be adhesively luted with pre-heated conventional light-cure RBC under controlled light-irradiation conditions. This strategy even seems beneficial in terms of mini-iFT compared to using a dual-cure luting RBC. IDS with lower filler content also appeared more favorable. [ABSTRACT FROM AUTHOR]

Purpose: Despite the high success rate of implant-supported fixed restorations in dentistry, there is a lack of evidence on the marginal seal for dental cement. Thus, this study aimed to evaluate the marginal seal of implant-supported crowns and partial dentures cemented using four different dental cements. Materials and Methods: The study evaluated the marginal seal of implant-supported crowns and partial dentures cemented using zinc phosphate, resin-modified glass-ionomer, self-adhesive resin, and noneugenol, acrylic-urethane polymer-based temporary dental cements. After cementation and thermal cycling procedures, the samples were incubated in Escherichia coli suspension for 5 days at 37°C under an aerobic environment. After debonding the restorations under sterile conditions, sterile cotton swabs were used to obtain microbial samples from the inner surface of each restoration and abutment surface. To analyze the contamination, each sample was immersed in a brain-heart infusion culture medium and incubated at 37°C for 24 hours, and then, the colony-forming units were counted and recorded. Results: Regarding the number of colonies for Escherichia coli, the results revealed no substantial difference between the crowns and the fixed partial restorations (P = .25). However, the differences in the level of contamination between the cement groups were significant (P = .001). The self-adhesive resin cement samples showed the lowest level of contamination, followed by the zinc phosphate and resin-modified glassionomer cements. The difference in the level of contamination between these groups was not significant. The temporary cement group exhibited significantly higher numbers of bacterial colonies in comparison to the other cement groups. Conclusion: Self-adhesive resin cement has better biologic properties for retaining implant-supported restorations than other types of dental cement. [ABSTRACT FROM AUTHOR]

Statement of problem: One of the main challenges facing dental implant success is peri-implantitis. Recent evidence indicates that titanium (Ti) corrosion products and undetected-residual cement are potential risk factors for peri-implantitis. The literature on the impact of various types of dental cement on Ti corrosion is very limited. Purpose: This study aimed to determine the influence of dental cement on Ti corrosion as a function of cement amount and type. Materials and methods: Thirty commercially pure Ti grade 4 discs (19 × 7mm) were polished to mirror-shine (Ra ≈ 40 nm). Samples were divided into 10 groups (n = 3) as a cement type and amount function. The groups were no-cement as control, TempBond NE (TB3mm, TB5mm, and TB8mm), FujiCEM-II (FC3mm, FC5mm, and FC8mm), and Panavia-F-2.0 (PC3mm, PC5mm, and PC8mm). Tafel’s method estimated corrosion rate (icorr) and corresponding potential (Ecorr) from potentiodynamic curves. Electrochemical Impedance Spectroscopy (EIS) data was utilized to obtain Nyquist and Bode plots. An equivalent electrical circuit estimated polarization resistance (Rp) and double-layer capacitance (Cdl). Inductively coupled plasma mass spectrometry (ICP-MS) analysis was conducted to analyze the electrolyte solution after corrosion. pH measurements of the electrolyte were recorded before and after corrosion tests. Finally, the corroded surface was characterized by a 3D white-light microscope and scanning electron microscope. Statistical analysis was conducted using either one-way ANOVA followed by Tukey’s Post Hoc test or Kruskal-Wallis followed by Dunn’s test based on data distribution. Results: Based on cement amount, FC and PC significantly increased icorr in higher amounts (FC8mm-icorr = 8.22 × 10−8A/cm2, PC8mm-icorr = 5.61 × 10−8A/cm2) compared to control (3.35 × 10−8A/cm2). In contrast, TB3mm decreased icorr significantly compared to the control. As a function of cement type, FC increased icorr the most. EIS data agrees with these observations. Finally, corroded surfaces had higher surface roughness (Ra) compared to non-corroded surfaces. Conclusion: The study indicated that cement types FC and PC led to increased Ti-corrosion as a function of a higher amount. Hence, the implant stability could be impacted by the selection, excessive cement, and a potentially increased risk of peri-implantitis.

Copyright of Archeologické Rozhledy is the property of Academy of Sciences of the Czech Republic, Institute of Archaeology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Odontologica Latinoamericana: AOL is the property of Acta Odontologica Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Enhancement of students’ knowledge is essential in improving their clinical skills and performance. Thus, the curriculum should be prepared to achieve a better outcome. The current study aimed to determine the dental students’ and interns’ basic knowledge towards dental luting cements and their application in dental practice to improve the theoretical and clinical training sections. Materials and methods A cross–sectional study was conducted among dental students and interns at three Colleges of Dentistry in the Kingdom of Saudi Arabia between September 2019–June 2020. An online questionnaire was used which included demographic data, questions about luting cement usage, cementation techniques, and commonly used cements in dental clinics. Descriptive analysis and chi–square test were used to show the association between level of dental education and the use of dental cements using SPSS software. The significance level was set at 5%. Results The total respondents were 626 dental students/interns of whom 78.8% were undergraduate dental students. Participants who reported undergraduate studies as the source of information were 79.7%. The type of restoration was the main factor in luting cement selection (62.6%). Concerning the isolation technique in cementing laminate veneers, 49.7% used dri–angles, cotton rolls and saliva ejectors. Dual–cure resin cement was the most common cement used in all the mentioned restorations except in pressed porcelain laminate veneers and cement–retained implant–supported restorations. Conclusions Students’ knowledge and practice in managing dental implants and porcelain laminate veneers need to be improved. The selection of a luting agent for a given restoration by students and interns was based on the basic knowledge, available cement, and the type of restoration. Awareness towards the management of short prepared teeth and custom-made cast posts and cores is also limited.

Introduction: Cention N is an alkasite restorative material, containing alkaline fillers. It is assumed that Cention N can neutralize an acidic pH by releasing fluoride, calcium, and hydroxyl ions. This study aimed to compare the antibacterial activity of Cention N with conventional glass ionomer cement (GIC) and resin-modified glass ionomer cement (RMGIC).Methods: Twenty experimental specimens were prepared from each of the Fuji IX (GIC), Fuji II LC (RMGIC), and Cention N (alkasite) using a cylindrical-shaped mold. The specimens were placed in agar plates at 37°C and inoculated with S. mutans (ATCC 25175). After 48 hours, the diameter of growth inhibition zones was recorded for each group at different time intervals including 3, 6, 12, 24, and 48 h. The data were analyzed by one-way ANOVA and Tukey's HSD test with a confidence level of 0.05.Results: Cention N exhibited significantly higher antimicrobial activity against S. mutans at 3, 6, 24, and 48 h as compared to Fuji IX and Fuji II LC (P

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. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to evaluate the antibacterial and solubility properties of four luting cements in artificial saliva at varying pH and clarify the composition by chemical analysis. Samples of bioceramic (C1), two resin-modified glass ionomer (C2 and C3), and zinc phosphate (C4) cements were stored on media with Streptococcus mutans and artificial saliva (pH 4.6 and pH 6.5). The disc diffusion method was used to evaluate antibacterial activity. In the solubility test, cement discs were stored in artificial saliva (pH 4.6 and pH 6.5) and distilled water (pH 7). After 48 and 120 hours, the solubility of the cement specimens was determined. Chemical analysis was performed by X-ray fluorescence. The growth inhibition zones of S. mutans induced by C4 were the largest in any pH values tested (p

Background: Enhancement of students' knowledge is essential in improving their clinical skills and performance. Thus, the curriculum should be prepared to achieve a better outcome. The current study aimed to determine the dental students' and interns' basic knowledge towards dental luting cements and their application in dental practice to improve the theoretical and clinical training sections. Materials and methods: A cross–sectional study was conducted among dental students and interns at three Colleges of Dentistry in the Kingdom of Saudi Arabia between September 2019–June 2020. An online questionnaire was used which included demographic data, questions about luting cement usage, cementation techniques, and commonly used cements in dental clinics. Descriptive analysis and chi–square test were used to show the association between level of dental education and the use of dental cements using SPSS software. The significance level was set at 5%. Results: The total respondents were 626 dental students/interns of whom 78.8% were undergraduate dental students. Participants who reported undergraduate studies as the source of information were 79.7%. The type of restoration was the main factor in luting cement selection (62.6%). Concerning the isolation technique in cementing laminate veneers, 49.7% used dri–angles, cotton rolls and saliva ejectors. Dual–cure resin cement was the most common cement used in all the mentioned restorations except in pressed porcelain laminate veneers and cement–retained implant–supported restorations. Conclusions: Students' knowledge and practice in managing dental implants and porcelain laminate veneers need to be improved. The selection of a luting agent for a given restoration by students and interns was based on the basic knowledge, available cement, and the type of restoration. Awareness towards the management of short prepared teeth and custom-made cast posts and cores is also limited. [ABSTRACT FROM AUTHOR]

Introduction: Cention N is an alkasite restorative material, containing alkaline fillers. It is assumed that Cention N can neutralize an acidic pH by releasing fluoride, calcium, and hydroxyl ions. This study aimed to compare the antibacterial activity of Cention N with conventional glass ionomer cement (GIC) and resin-modified glass ionomer cement (RMGIC). Methods: Twenty experimental specimens were prepared from each of the Fuji IX (GIC), Fuji II LC (RMGIC), and Cention N (alkasite) using a cylindrical-shaped mold. The specimens were placed in agar plates at 37°C and inoculated with S. mutans (ATCC 25175). After 48 hours, the diameter of growth inhibition zones was recorded for each group at different time intervals including 3, 6, 12, 24, and 48 h. The data were analyzed by one-way ANOVA and Tukey's HSD test with a confidence level of 0.05. Results: Cention N exhibited significantly higher antimicrobial activity against S. mutans at 3, 6, 24, and 48 h as compared to Fuji IX and Fuji II LC (P<0.05). Conclusions: Cention N could be considered as a suitable alternative for glass ionomers and resin-modified glass ionomers concerning its caries-preventive effects. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to evaluate the antibacterial and solubility properties of four luting cements in artificial saliva at varying pH and clarify the composition by chemical analysis. Samples of bioceramic (C1), two resin-modified glass ionomer (C2 and C3), and zinc phosphate (C4) cements were stored on media with Streptococcus mutans and artificial saliva (pH 4.6 and pH 6.5). The disc diffusion method was used to evaluate antibacterial activity. In the solubility test, cement discs were stored in artificial saliva (pH 4.6 and pH 6.5) and distilled water (pH 7). After 48 and 120 hours, the solubility of the cement specimens was determined. Chemical analysis was performed by X-ray fluorescence. The growth inhibition zones of S. mutans induced by C4 were the largest in any pH values tested (p < 0.05). The solubility of C4 was significantly higher than the solubility of other cements. C2 had the smallest inhibition zones and was least soluble in all media during the observation period, but without significant differences. After 48 hours, the solubility of C4 was significantly higher at pH 4.6 compared to control. The solubility of the cements, excluding C2, was significantly higher after 120 hours at pH 6.5. A significant association was found between larger amount of zinc oxide in cement composition and a larger zone of inhibition. Lower solubility was associated with higher amounts of aluminium and silicon oxides in the cement. Thus, cement containing higher amounts of zinc oxides had the highest antibacterial activity. In the solubility test, cements were more soluble in acidic media than in neutral media, and lower solubility was detected in cements containing more aluminium and silicon oxides. In clinical practice, C1 or C3 may be suggested when there is a higher risk of caries due to more desirable combination of antibacterial activity and lower solubility, for a lower caries risk C2 might be suggested. [ABSTRACT FROM AUTHOR]

Dental replacements are placed between the abutment teeth. The exceptions are two-unit bridges, as they are supported by a single tooth prepared only on one side of the missing tooth. The presented study deals with an analysis of a pressure force action on two-unit bridges placed in the frontal part (20 samples), where the pressure action is lower, and in the distal part (20 samples), where the pressure action is higher. A CAD program by 3Shape was used for digital designing with two different gap settings, 10 μm (20 samples) and 30 μm (20 samples). Two-unit bridges were attached to the prepared tooth using two types of dental cement (20/20 samples), which were selected for their physical and bioactive properties. All two-unit bridges (a total of 80 samples) were fabricated from CoCr alloys on Mlab cusing R by applying the Selective Laser Melting (SLM) technology. Mechanical testing was performed using the Inspekt5 table blue. The obtained data were used to verify the hypotheses—a difference between both types of cement (A ≠ B), a difference between the frontal and distal two-unit bridges (F ≠ D) and a difference between the gap sizes (10 ≠ 30). To confirm the given theories, data were statistically evaluated using the F-test and subsequent t-tests. The resulting p-value was compared with the level of significance (α = 0.05). A statistical evaluation revealed a significant difference between the compared groups; however, no explicit correlation between the individual groups of specimens was identified. [ABSTRACT FROM AUTHOR]

α-Tricalcium phosphate/fluorapatite (α-TCP/FAp) mixed powders were prepared in order to obtain dental root canal filling cements. Different liquids for cement pastes have been investigated and the most suitable one for obtaining rheologically optimal pastes was chosen for further analysis. Morphological changes in the cement materials as a consequence of the formation of hydroxyapatite (HAp) after the immersion in a simulated body fluid (SBF), an influence on the cell viability, and final success of the filling were investigated by field emission scanning electron microscopy. Treatment of the α-TCP/FAp mixtures in SBF at 37°C resulted in a complete transformation of α-TCP into HAp after 10 days, while the exposure of MRC-5 human and L929 animal fibroblast cells to the cement showed complete absence of cytotoxicity. The root canal of an extracted tooth was filled with the α-TCP/FAp cement containing 5 wt.% of FAp and relatively strong adhesion between the cement and dentine was observed after 48h. The same cement material was immersed during 10 days in SBF and after that both human and animal fibroblast cells during in vitro MTT tests showed higher cell viability compared to the control sample. These findings lead to a conclusion that the α-TCP/FAp based cement demonstrates potential for further development towards dental cement application.

The aim of this study was to test the antimicrobial properties of dental cements modified with magnesium oxide (MgO) nanoparticles. Zein-modified MgO nanoparticles (zMgO) in concentrations (0.0, 0.3, 0.5, and 1.0%) were mixed with dental cements (Fuji II, Rely X Temp E, Ionoglass Cem, Es Temp NE, and System P link). Eight discs were fabricated from each zMgO-cement pair for a total of 32 specimens for each cement. Characterization of the dental cements incorporating zMgO was done by X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). The antimicrobial properties of the mixtures were tested using direct contact and agar diffusion assays against Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans. Data was analyzed using two-way analysis of variance and LSD post hoc test at 0.05 significance level. XRD spectra showed sharp peaks of zMgO indicating its high crystalline nature, while the amorphous dental cements with zMgO had broad peaks. FESEM analysis showed a uniform distribution of the zMgO nanoparticles in the cement. There were significant inhibition zone values associated with all concentrations of zMgO-cement mixtures tested compared to controls (p < 0.001) with a dose-response recorded only with Fuji II. Optical density values were significantly lower in zMgO groups compared to controls for all microorganisms. The effect was most prominent with Rely X against C. albicans and S. aureus. Dental cements containing zMgO showed significant antimicrobial properties that were dependent on the specific initial cement substrate.

This work is part of a larger study whose main objective was to find a series of promising molecules to be used as glass-ionomer-type materials. The project was divided into 3 successive stages; the results of the first stage have been previously published and were used to continue the study. The molecules evaluated in the second stage were constructed by adding a glycidyl methacrylate molecule to the carboxylic groups of the polyacids selected in the previous stage. The modeling was done using the density functional theory for M06-2X/6-311G(d,p). The results indicate that the addition over the carboxylic groups of the fraction of the molecule, corresponding to itaconic acid, is thermodynamically favored. The final stage was modeled with the M06 functional and consisted of obtaining basic structures of glass-ionomer-type materials, by acid–base reaction between the molecules resulting from the second stage with individual ions of Ca (2 +), Zn (2 +), or Al (+ 3). It was concluded that aluminum atoms generate more compact structures that would correlate with more resistant materials. [ABSTRACT FROM AUTHOR]

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.

The objective of this study was to compare retention strength of various cement types in bonding polyetheretherketone (PEEK) abutments to polymethyl methacrylate (PMMA) crowns and their failure modes. After PEEK abutments preparation, the surface roughness, surface topography and energy dispersive x-ray spectroscopy (EDS) analysis were examined to confirm the same surface characteristics. Then, fifty PEEK abutments were divided into 5 groups (n=10), one for each cement type. Clear PMMA crowns were cemented to abutments using zinc phosphate cement (ZPC), zinc oxide temporary cement without eugenol (Temp-Bond™ NE) and three resin cements (RelyX™ U200, Panavia™ F 2.0, and Superbond C&B ®). The retention strength and failure modes were examined using a universal testing machine and stereomicroscope. The results were analyzed with One-way ANOVA at a significance level of 0.05. The surface roughness, topography, and EDS analysis confirmed the same surface characteristic of all PEEK abutment specimens. Statistical analysis revealed significant difference across cements groups (p<0.01). The highest retention strength was Superbond C&B ® followed by RelyX™ U200, Panavia™ F 2.0, Temp-Bond™ NE, and ZPC respectively. All of the specimens in each group exhibited mixed failure mode except the Superbond C&B ® group. Within the limitation of this in vitro study, Superbond C&B ® exhibited the highest retention strength, whereas RelyX™ U200, Panavia™ F 2.0, Zinc phosphate cement, and Temp-Bond™ NE failed to provide sufficient retention strength. [ABSTRACT FROM AUTHOR]

Durable resin-ceramic adhesion may influence the clinical success of ceramic restorations, which has been one of the challenging issues in dentistry. The present study assessed the bond strength and chemical interaction of 10-methacryloxydecyl dihydrogen phosphate (MDP), MDP+silane, and MDP-salt primers to alumina-blasted zirconia ceramic by tensile bond strength test, surface elemental composition with x-ray photoelectron spectroscopy analysis, contact angle measurement, surface morphology with scanning electron microscopy, and surface topography with 3-dimensional confocal laser scanning microscope analyses. MDP-salt showed the highest tensile bond strength before and after thermocycling when compared with MDP and MDP+silane (P < 0.05). The measured contact angle values differed significantly (P < 0.001) in the order of MDP-salt > control (no chemical pretreatment) > MDP+silane > MDP. There was no difference in surface roughness (P = 0.317) and surface topography among all tested groups. Zirconia treated with MDP-salt showed phosphorus peaks in addition to zirconia and alumina peaks. MDP-salt has zirconia priming properties, which improves bonding performance to resin cement. [ABSTRACT FROM AUTHOR]

Introduction: Aim of this study is to compare shear bond strength of different luting materials used in fixed space maintainer cementation. Methods: Thirty intact extracted human third molars randomly divided into three equal groups: group A: RelyX luting 2 (resin modified glass ionomer); group B: TOTALCEM (self-adhesive resin cement/ dual cure); group C: Transbond plus (compomer). After bonding procedures, the samples were kept in distilled water at 37°C for 24 hours prior to the shear bond strength test. Data were analyzed blindly by one-way ANOVA test and the Tukey post hoc test using R software. Results: There were statistically significant differences between the three luting materials (P < 0.001). Conclusion: TOTALCEM showed significantly higher shear bond strength than RelyX luting 2 and Transbond plus. With respect to limitations of in vitro studies, long-term clinical studies required.

Background: Polyether ether ketone (PEEK) was recently introduced to dentistry. However, difficulty in provision of a strong durable bond is its main drawback. Thus, precise surface treatment and use of a suitable luting agent are imperative for bonding of PEEK restorations. This study aimed to assess the effect of type of luting agent on shear bond strength (SBS) of PEEK. Materials and Methods: In this in vitro study, 60 square-shaped PEEK samples were fabricated and sandblasted with 110 µm Al2O3 particles. The samples were then divided into four groups based on the type of cement used (n = 15): zinc phosphate cement, Panavia F2, Panavia V5, and resin-modified glass-ionomer (RMGI) cement. After bonding, the samples were thermocycled for 5000 cycles. The SBS was measured by a universal testing machine. The surface of samples was inspected under a video measuring machine to determine the mode of failure. Data were analyzed using the Kruskal-Wallis test via SPSS version 24 (α = 0.05). Results: RMGI did not bond to PEEK. The SBS values were 4.02 ± 2.87 megapascals (MPa) for Panavia V5, 10.84 ± 6.05 MPa for Panavia F2, and 10.50 ± 2.88 MPa for zinc phosphate. The SBS in the Panavia V5 group was significantly lower than that in the Panavia F2 (P = 0.001) and zinc phosphate (P < 0.001) groups. No significant difference existed between the Panavia F2 and zinc phosphate groups in this respect (P > 0.05). Conclusion: Panavia F2 resin cement and zinc phosphate conventional cement provided the highest bond strength to PEEK, while RMGI did not bond to PEEK. [ABSTRACT FROM AUTHOR]

Introduction: Practices followed by dentists for restoring endodontically treated teeth (ETT) vary with a variety of available techniques and materials for post- and-core restorations. The aim of this study was to identify concepts for restoring ETT among dentists in Jeddah, Saudi Arabia. Materials and Methods: A two-section questionnaire was developed using online web-based application (Google forms) and sent to 400 dentists. The first section collected demographic information and the second section concerned about the treatment concept and materials for restoring ETT. Descriptive statistics were used to analyze the data, followed by Chi-square or Fisher's exact test to compare the responses to different questions among general dentists and specialists/consultants. Results: A total of 138 questionnaires were completed. Most of the participants reported a frequently or always use of extracoronal restoration in anteriors (55.1%), premolars (89.1%) and 88.4% for molars. Participant reported frequent placement of posts in anteriors (56.5%), premolars (84.1%) and 64.5% for molars. Nonmetallic post and cast post and core were the preferred option for anteriors and molars, while responses were equally divided between nonmetallic post and cast post and core for premolars. Composite resin was the preferred core material for all teeth. Conclusions: The use of endodontic posts, composite resin as a core and extracoronal restoration for restoring ETT is common among participants. Some of the concepts expressed by the participants are outdated and does not coincide with the evidence-based practice.

The objective was to synthesize ionomer-type cements from alkaline-activated kaolinite and describe their setting characteristics, compressive strength and fluoride ion releasing properties. Aluminosilicate phases were visible on XRD spectra with minimal difference between raw and alkaline-activated kaolin. D50 range of sieved powders was 8.10–9.07 μm. Characteristic bands of polyacrylates and tartrates were identifiable in the cements on FTIR. Cements were hydrolytically stable with mixing and setting times of 60s and 135–240 s, respectively. Mean compressive strength increased over time, highest value 3.24 MPa recorded for Kaolin100 after 28 days, and significantly different within the group (F = 76.64, p = 0.000). Cement containing fly ash (FA) exhibited fluoride ion release capabilities with Kaolin80FA20 having the highest 0.69 mmol/L at 60 min. Mechanically weak but hydrolytically stable ionomer cements can be formulated from alkaline-activated kaolin geopolymers.

• Copper bioglass nanoparticles incorporated in ZPC (Cu-ZPC) was proposed. • Cu-ZPC exhibited therapeutic ion releases such as Zn, Cu, Ca and Si. • Cu-ZPC showed higher odontoblastic differentiation using dental pulp human cells. • Cu-ZPC inhibited the growth and attachment of E. faecalis. [Display omitted] This study was investigated the mechanophysical properties of zinc phosphate cement (ZPC) with or without the copper doped bioglass nanoparticles (Cu-BGn) and their biological effect on dental pulp human cells and bacteria. Cu-BGn were synthesized and characterized firstly and then, the experimental (Cu-ZPC) and control (ZPC) samples were fabricated with similar sizes and/or dimensions (diameter: 4 mm and height: 6 mm) based on the International Organization of Standards (ISO). Specifically, various concentrations of Cu-BGn were tested, and Cu-BGn concentration was optimized at 2.5 wt% based on the film thickness and overall setting time. Next, we evaluated the mechanophysical properties such as compressive strength, elastic modulus, hardness, and surface roughness. Furthermore, the biological behaviors including cell viability and odontoblastic differentiation by using dental pulp human cells as well as antibacterial properties were investigated on the Cu-ZPC. All data were analyzed statistically using SPSS® Statistics 20 (IBM®, USA). p < 0.05 (*) was considered significant, and 'NS' represents nonsignificant. Cu-BGn was obtained via a sol-gel method and added onto the ZPC for fabricating a Cu-ZPC composite and for comparison, the Cu-free-ZPC was used as a control. The film thickness (≤ 25 µm) and overall setting time (2.5–8 min) were investigated and the mechanophysical properties showed no significance ('NS') between Cu-ZPC and bare ZPC. However, cell viability and odontoblastic differentiation, alkaline phosphate (ALP) activity and alizarin red S (ARS) staining were highly stimulated in the extracts from the Cu-ZPC group compared to the ZPC group. Additionally, the antibacterial test showed that the Cu-ZPC extracts were more effective than the ZPC extracts (p < 0.05). Cu-ZPC showed adequate mechanophysical properties (compressive strength, hardness, and surface roughness) and enhanced odontoblastic differentiation as well as antibacterial properties compared to the ZPC-only group. Based on the findings, the fabricated Cu-ZPC might have the potential for use in the field of dental medicine and clinical applications. [ABSTRACT FROM AUTHOR]

Optogenetics enables activation/silencing of specific neurons with unprecedented temporal and spatial resolution. The method, however, is prone to artefacts associated with biophysics of light used for illuminating opsin-expressing neurons. Here we employed Tph2-mhChR2-YFP transgenic mice, which express channelrhodopsin (ChR2) only in serotonergic neurons in the brain, to investigate behavioral effects of optogenetic stimulation of serotonergic neurons. Surprisingly, optogenetic stimulation enhanced locomotion even in ChR2-negative mice. Such unspecific effects are likely to be due to visual agitation caused by light leakage from the dental cement, which is commonly used to fixate optic fiber ferrules on the skull. When we employed black dental cement made by mixing carbons with dental cement powders, such unspecific effects were abolished in ChR2-negative mice, but not in ChR2-positive mice, confirming that enhanced locomotion resulted from serotonergic activation. The method allows extracting genuine behavioral effects of optogenetic stimulation without contamination from visual stimuli caused by light leakage.

Background: The primary function of dental cement is to seal and support prosthodontic restorative materials. Proper selection of the dental cement contributes to the clinical success of the restoration., Methods: A total of 166 molar tooth samples were prepared to simulate the type of tooth commonly found in prosthodontic practice. Each sample was restored using one of the tested dental cement materials employing a prestabilized methodology. The performance of resin-modified glass ionomer cement (RMGIC) (GC Fuji PLUS Capsule, GC America, Alsip, IL), zinc phosphate cement (ZPC) (Dentsply Sirona, Charlotte, NC), and resin cement (RC) (RelyX ARC, 3M ESPE, Saint Paul, MN) in bonding strength, marginal adaptation, and microleakage was evaluated and compared. The bonding strength, marginal adaptation, and microgroove were tested using specific established methodologies. The outcomes were then analyzed using statistical analyses for means and standard deviations to compare different types of dental cement., Results: The total outcome shows that the highest bonding strength with the highest mean was the resin cement, rating 24.8 MPa, followed by RMGIC and ZPC at 20.5 and 18.9 MPa, respectively. The marginal adaptation scores indicate that RC had the highest score at a mean of 4, followed by ZPC at 3.2 and RMGIC at 2.5. The dye penetration measurements in millimeters revealed that ZPC had a penetration of 0.31 mm, RMGIC had a penetration of 0.25 mm, and RC had the least penetration at 0.20 mm. The results of the statistical data analysis show significant differences between the dental cements in bonding strength and marginal adaptation., Conclusion: In conclusion, resin cement demonstrated superior performance in bonding strength, marginal adaptation, and resistance to microleakage compared to RMGIC and zinc phosphate cement. These findings highlight the importance of selecting resin cement for achieving optimal clinical outcomes in prosthodontic restorations., Competing Interests: Human subjects: All authors have confirmed that this study did not involve human participants or tissue. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Hussain Alhamoudi et al.)

Dental replacements are placed between the abutment teeth. The exceptions are two-unit bridges, as they are supported by a single tooth prepared only on one side of the missing tooth. The presented study deals with an analysis of a pressure force action on two-unit bridges placed in the frontal part (20 samples), where the pressure action is lower, and in the distal part (20 samples), where the pressure action is higher. A CAD program by 3Shape was used for digital designing with two different gap settings, 10 μm (20 samples) and 30 μm (20 samples). Two-unit bridges were attached to the prepared tooth using two types of dental cement (20/20 samples), which were selected for their physical and bioactive properties. All two-unit bridges (a total of 80 samples) were fabricated from CoCr alloys on Mlab cusing R by applying the Selective Laser Melting (SLM) technology. Mechanical testing was performed using the Inspekt5 table blue. The obtained data were used to verify the hypotheses—a difference between both types of cement (A ≠ B), a difference between the frontal and distal two-unit bridges (F ≠ D) and a difference between the gap sizes (10 ≠ 30). To confirm the given theories, data were statistically evaluated using the F-test and subsequent t-tests. The resulting p-value was compared with the level of significance (α = 0.05). A statistical evaluation revealed a significant difference between the compared groups; however, no explicit correlation between the individual groups of specimens was identified.

Introduction: Aim of this study is to compare shear bond strength of different luting materials used in fixed space maintainer cementation. Methods: Thirty intact extracted human third molars randomly divided into three equal groups: group A: RelyX luting 2 (resin modified glass ionomer); group B: TOTALCEM (self-adhesive resin cement/ dual cure); group C: Transbond plus (compomer). After bonding procedures, the samples were kept in distilled water at 37°C for 24 hours prior to the shear bond strength test. Data were analyzed blindly by one-way ANOVA test and the Tukey post hoc test using R software. Results: There were statistically significant differences between the three luting materials (P < 0.001). Conclusion: TOTALCEM showed significantly higher shear bond strength than RelyX luting 2 and Transbond plus. With respect to limitations of in vitro studies, long-term clinical studies required. [ABSTRACT FROM AUTHOR]

Purpose: Peri-implantitis is a disease characterized by soft tissue inflammation and continued loss of supporting bone, which can result in implant failure. Peri-implantitis is a multifactorial disease, and one of its triggering factors may be the presence of excess cement in the soft tissues surrounding an implant. This descriptive study evaluated the composition of foreign particles from 36 human biopsy specimens with 19 specimens selected for analysis. The biopsy specimens were obtained from soft tissues affected by peri-implantitis around cement-retained implant crowns and compared with the elemental composition of commercial luting cement. Materials and Methods: Nineteen biopsy specimens were chosen for the comparison, and five test cements (TempBond, Telio, Premier Implant Cement, Intermediate Restorative Material, and Relyx) were analyzed using scanning electron microscopy equipped with energy dispersive x-ray spectroscopy. This enabled the identification of the chemical composition of foreign particles embedded in the tissue specimens and the composition of the five cements. Statistical analysis was conducted using classification trees to pair the particles present in each specimen with the known cements. Results: The particles in each biopsy specimen could be associated with one of the commercial cements with a level of probability ranging between .79 and 1. TempBond particles were found in one biopsy specimen, Telio particles in seven, Premier Implant Cement particles in four, Relyx particles in four, and Intermediate Restorative Material particles in three. Conclusion: Particles found in human soft tissue biopsy specimens around implants affected by peri-implant disease were associated with five commercially available dental cements. [ABSTRACT FROM AUTHOR]

Background and Objectives: Ceramic veneers represent the most appropriate treatment option for minimally invasive aesthetic rehabilitation. For long-term clinical success, the accurate marginal and internal adaptation of dental restorations are of paramount importance. The aim of this in vitro study is to assess the effect of a novel (patented) design of veneers compared to conventional ones on their marginal and internal gap to the prepared tooth surface. Materials and Methods: Twenty-four lithium disilicate ceramic veneers are obtained using Computer-Aided-Design (CAD) and then milled using Computer-Aided-Manufacturing (CAM). The samples are divided into two groups: 12 conventional (CO) veneers (i.e., with a linear marginal contour) and 12 crenelated (CR) veneers, the latter with the novel sinusoidal marginal design. All samples are bonded to frontal teeth, and the adhesive interfaces are analyzed using two methods, optical microscopy and micro-Computed Tomography (CT): the former for the accuracy of the marginal gap and the latter for the internal gap (as well as for the homogeneity of the luting cement) of ceramic veneers. Results: STATA and one-way ANOVA tests reveal significant differences between CO and CR veneers: (i) the marginal gap is smaller for CR (64 μm) than for CO veneers (236 μm); (ii) the internal adaptation is better for CR veneers: for a cement width of up to 120 μm, the covered surface for the CR group is 81.5%, while for the CO group it is 64.5%; (iii) the mean of the porosities within the cement is not significantly different (3.4106 μm³ for CO and 3.9106 μm³ for CR veneers), with a higher standard deviation for the CO group. Analytical modeling is achieved for internal gaps using the micro-CT results. The characteristic functions obtained allow us to compare the volume of luting cement for the two types of veneers. Conclusion: The novel veneers design produces an improvement in the marginal and internal adaptation of the restorations to the prepared tooth surface. Thus, it provides favorable premises for better clinical performances. [ABSTRACT FROM AUTHOR]

Background: The margin of crown is a significant area for plaque accumulations. Therefore, the ability of the cement to seal the margin is very important. The aim of the present study was to evaluate the bond (retentive) strength, microleakage, and failure mode of four different types of cements in stainless steel crown (SSC) of primary molar teeth. Materials and Methods: In this experimental study, eighty extracted primary molar teeth were divided into two groups of forty teeth to test the microleakage and bond strength. The crowns were cemented according to the manufacturer guidelines with four cement types including self-cure glass ionomer, resin-modified glass ionomer, polycarboxylate, and resin cements. Stereomicroscope and universal testing machine were used to measure the microleakage and bond strength, respectively. For calculating the surface area of crowns, three-dimensional scanning was used. Furthermore, the failure mode was examined after the bond strength test. The cements surfaces and the tooth--cement interfaces were evaluated using scanning electron microscopy (SEM). The obtained values were analyzed using SPSS-23 software through Shapiro--Wilk and one-way analysis of variance tests. Means, standard deviations, medians, and interquartile ranges were calculated. P < 0.05 was considered as statistically significant in all analyses. Results: Significant differences between microleakage (P = 0.001) and failure mode (P = 0.041) of the four types of cements were obtained. However, the mean bond strengths of the four groups did not differ significantly (P = 0.124). The obtained SEM images confirmed the results of bond strength and microleakage. Conclusion: Resin cement and resin-modified glass ionomer, respectively, showed superior properties and are recommended for use in SSCs of primary molar teeth. [ABSTRACT FROM AUTHOR]

Dental cements have been established in practice since 1878, and technological advances in the field of implant pros-thetics have directly influenced the development of materials in this area. Although the retention type of implant-supported restorations can be dual, it is nowadays known that the overall rate of technical complications is higher for cement-retained restorations by 2% over screw-retained restorations. Biological complications, including peri-implant mucositis, periimplantitis, bone loss around implants, soft-tissue recession and fistula suppuration, are also more frequent with cement-retained restorations. The most common of these, periimplantitis is often related to factors depending on a clinician.

Background: This study aimed to compare the effect of four temporary luting agents on preventing the coronal microleakage of teeth restored with custom cast post and core. Materials and Methods: In this in vitro original study, after removing 9 mm of gutta percha from root canals of 32 single-canaled premolars, the acrylic resin patterns of the post and core were fabricated. Patterns were cast with Ni-Cr metal alloy and then cemented with glass ionomer. Using self-curing acrylic resin, provisional restorations were made. Then, teeth were randomly allocated to four groups for each temporary cement including zinc oxide eugenol (Temp Bond), zinc oxide noneugenol (Temp Bond NE), noneugenol resin-based temporary luting agent (Temp Bond Clear), and noneugenol urethane methacrylate polymer-based temporary luting agent (Dento temp). Teeth were subjected to thermocycling, immersed in silver nitrate for 6 h and then sectioned. The amount of dye penetration in the margin of provisional crown and into the coronal part of the root canals was measured using a stereomicroscope. Data were analyzed using the Kruskal--Wallis and Dunn tests with significance level of 0.05. Results: All the luting agents showed some degree of microleakage (Group 1 showed the most microleakage). According to the pair comparison between the groups, Group 1 revealed a significant difference with others (P < 0.05). Furthermore, Group 2 showed more microleakage as compared to Group 4 (P = 0.037). Conclusion: Temp Bond showed the highest microleakage as compared to other luting agents. Furthermore, Temp Bond NE revealed a weaker sealability as compared to Dento temp. [ABSTRACT FROM AUTHOR]

Background: To consciously select an appropriate dental cement for each type of intracanal post. Materials and Methods: An electronic search was carried out (1970 to 2020) through Medline, PubMed, Scopus, and Google Scholar. The following keywords were searched in title, abstract, or keywords with different combinations: endodontically treated tooth, root canal therapy, dental posts, post and core, prefabricated posts, custom posts, dental cement, resin cements, cement selection, cement, and adhesive resin cement. Results: Evaluating full texts, 146 articles were selected to review the types of posts and cements, selection criteria of appropriate cement for each type of post, and compare the results obtained by different cements. Conclusion: Dental cements affect the survival rate, durability, and success rate of postbased treatments. Considering special characteristics and application of each type of intracanal post, conscious selection of cement is an important determining factor in long-lasting success. Choosing an appropriate cement has a key role in success and durability of dowel posts-based fixed restorations.

Background: Polyether ether ketone (PEEK) was recently introduced to dentistry. However, difficulty in provision of a strong durable bond is its main drawback. Thus, precise surface treatment and use of a suitable luting agent are imperative for bonding of PEEK restorations. This study aimed to assess the effect of type of luting agent on shear bond strength (SBS) of PEEK. Materials and Methods: In this in vitro study, 60 square-shaped PEEK samples were fabricated and sandblasted with 110 μm Al2O3 particles. The samples were then divided into four groups based on the type of cement used (n = 15): zinc phosphate cement, Panavia F2, Panavia V5, and resin-modified glass-ionomer (RMGI) cement. After bonding, the samples were thermocycled for 5000 cycles. The SBS was measured by a universal testing machine. The surface of samples was inspected under a video measuring machine to determine the mode of failure. Data were analyzed using the Kruskal–Wallis test via SPSS version 24 (α = 0.05). Results: RMGI did not bond to PEEK. The SBS values were 4.02 ± 2.87 megapascals (MPa) for Panavia V5, 10.84 ± 6.05 MPa for Panavia F2, and 10.50 ± 2.88 MPa for zinc phosphate. The SBS in the Panavia V5 group was significantly lower than that in the Panavia F2 (P = 0.001) and zinc phosphate (P < 0.001) groups. No significant difference existed between the Panavia F2 and zinc phosphate groups in this respect (P > 0.05). Conclusion: Panavia F2 resin cement and zinc phosphate conventional cement provided the highest bond strength to PEEK, while RMGI did not bond to PEEK.

Implants provide support, stability and retention for restorations used in fully and partially edentulous patients. This clinical report describes prosthetic treatment of a 30-year-old man suffering from a dentoalveolar deficiency due to an old gunshot trauma to the left side of the mandible. The patient was rehabilitated with implant-supported Toronto prosthesis following surgical placement of three implants with undesirable location and angulations due to lack of sufficient bone. This prosthetic option offers advantages of both screw-retained and cement-retained prostheses and provides acceptable aesthetic and functional results.

Background and Aims: Loss of retention is one of the main reasons of failure in teeth restored with post and core. Several factors, including the type of cement can influence the retention of the posts. As zinc phosphate cement is considered as the standard for comparison this study performed to review articles evaluating the retention of cast posts cemented with zinc phosphate. Materials and Methods: This systematic review was performed based on the PRISMA (Transparent Reporting of Systematic Reviews and Meta-analyses) guide. The question of this study was that how much is the amount of retention of cast posts cemented with zinc phosphate. Hence, a literature search was done in PubMed and Medline databases as well as Google scholar search engine using relevant keywords until 2016 limited to the English language. Articles were selected based on the inclusion and exclusion criteria, and were evaluated qualitatively. Resultes: Internet search resulted in 1141 articles. Following the application of inclusion and exclusion criteria, 6 studies were included in this systematic review. The most common post material was nickel-chromium alloy. Retention of casting posts cemented by zinc phosphate was from 8.76 to 34.2 Kg and from 91 to 192.2 N. Conclusion: Our review showed that the retention of cast posts cemented with zinc phosphate in controlled condition is moderate and factors including post material and length could influence the retention of the post.

To evaluate the shear bond strength (SBS) between Y-TZP and a resin luting agent, after 1 of 2 enhancing strategies with TiO 2- -nts was applied, either to the resin luting agent or the Y-TZP mass, in different concentrations. In the Strategy TiO 2 -nts on ceramic, the resin luting agent Panavia F2.0™ (Kuraray) and an experimental Y-TZP with added concentrations of TiO 2- -nts (0%, 1%, 2%, and 5% vol/vol) and a commercial Y-TZP, comprised 5 different groups (n = 10). In the Strategy TiO 2 -nts on cement, the resin luting agent RelyX U200™ (3 M ESPE) was added with different concentrations of TiO 2- -nts (0%, 0.3%, 0.6%, 0.9% wt/wt) luted to a commercial Y-TZP, comprising 4 different groups (n = 10). The Y-TZP discs were included in acrylic bases, and a cylinder (3 × 3 mm) of the correspondent luting agent for each respective group was applied over them. After 24 h, specimens were subjected to SBS assessments in a universal testing machine. Field emission scanning electron microscopy and energy dispersive X-ray spectroscopy analyses were also performed on Y-TZP surfaces. Data were analyzed via analysis of variance and Tukey tests (α = 0.05). TiO 2 -nts on ceramic influenced the bond strength significantly, but not linearly; TiO 2 -nts on cement did not influence bond strength when analyzed separately, nor in comparison with the first. Y-TZP enhancements with TiO 2 -nts led to a higher SBS with Panavia F2.0, a 5% TiO 2- -nt concentration presented the highest bond strength. Modified Rely X U200 did not improve SBS. [ABSTRACT FROM AUTHOR]

The main purpose of this article is to compare the mineral trioxide aggregate and calcium hydroxide in pediatric dentistry. Both of the endodontic cement are frequently used in different cases of pedodontics. This article aims to present the various characteristics of mineral trioxide aggregate and calcium hydroxide in a review article. [ABSTRACT FROM AUTHOR]