فهرست مطالب nooshin sadat shojaee

Injuries to the mouth and teeth due to various incidents have a high prevalence in society; therefore, it is necessary to diagnose them and provide a suitable treatment plan for them. The purpose of this research is to design, implement and evaluate smartphone-based software for dental treatment in oral and dental injuries in pediatric patients. This study is an applied-production study conducted in three stages: The first step is the preparation and design of algorithms, the second stage is the introduction of diagnostic and therapeutic algorithms into the software system, and in the third stage, the software system is evaluated for its efficiency and accuracy in diagnosing and providing a treatment plan. The samples were all 77 patients who were referred to the trauma department of Shiraz Dental School from June to July 2019. There was a significant correlation between the resident and the professor’s diagnosis with the software diagnosis, with 92.2% complete compliance, 3.9% relative compliance, and 3.9% non-compliance (kappa value = 0.91, P value < 0.0001). The accuracy and high speed of diagnosis and the offered treatment plan for all types of oral and dental trauma were acceptable. However, the software cannot replace a specialist and should be used in combination with expert opinion.

Statement of the Problem: 

One of the annoying problems related to almost all root canal preparation systems, which may cause flare-ups and impairment in the healing process is the extrusion of intracanal debris.

This study was conducted to evaluate the amount of apically-extruded debris during root canal preparation using Medin (MEDIN Co., Czech Republic) rotary system compared with two common rotary systems, including Protaper (Dentsply Maillefer., Switzerland) and RaCe (FKG Dentaire, Switzerland).

Sixty mandibular premolars with single canal were randomly assigned to three groups (n=20). The root canals were prepared with Medin, Protaper and RaCe rotary instruments based on their manufacturers’ instructions. The debris were collected into pre-weighted Eppendorf tubes. The weight of the extruded debris was calculated by subtracting the pretreatment weight of the vials. Data were analyzed using the Kruskal-Wallis test at a 5% significance level.

Medin instrument caused significantly less debris extrusion in comparison with Protaper and Race (p < 0.05). The differences between the Protaper and Race rotary systems were not statistically significant (p = 0.752).

Within the limitations of this in vitro study, Medin rotary system produced less apical extrusion than Protaper and Race.

The complete removal of filling material is an important step to regain access to the entire canal and facilitate the disinfection of the root canal system. Rotary nickel–titanium (NiTi) instruments systems have been proposed as an effective removal technique for root canal retreatment.

The aim of this study was to evaluate the efficacy of Neolix rotary system and ProTaper Universal retreatment system in the removal of gutta-percha combined with two different sealers.

In vivo study, eighty extracted human permanent mandibular premolarswere prepared using the ProTaper Universal rotary system to an apical size 30 (F3/0.06). The specimens were randomly divided into 4 groups (n=20) and subsequently filled with lateral condensation of gutta-percha and two sealers: AH-26 and Sure-Seal Root. The teeth were stored for 4 weeks at 37°C and 100% humidity and then retreated by one of the following rotary systems: Neolix or ProTaper Universal retreatment system. Teeth were then grooved and monitored under a stereomicroscope with 8× magnification. The images were transferred to the computer and the amount of filling material that remained on the root canal walls was scored using AutoCAD 2017 version 1.1software. Results were analyzed using one-way analysis of variance test and post hoc Tukey-HSD test (p< 0.05).

The mean percentage of remaining gutta-percha and sealer was significantly higher in apical third in all groups (p< 0.01). Post hoc Tukey test showed that there is significantly higher residual filling material in the group filled with gutta-percha and Sure-Seal Root sealer and retreated by Neoniti rotary system compared with other groups in both coronal and middle third of the canal.

The Neoniti rotary system was as effective as ProTaper Universal retreatment system in retreatment of gutta-percha and AH-26 sealer but was significantly less effective in groups obturated with Sure-Seal Root sealer.

The aim of this study was to evaluate the effect of different water-to-powder (WP) proportions on the microhardness and water solubility of calcium-enriched mixture (CEM) cement. Methods and Materials: One gram of CEM cement powder was mixed with 0.33 mL, 0.4 mL or 0.5 mL CEM liquid. For water solubility, a total of 60 specimens were prepared (n=20 per each ratio) in the disk-shaped stainless-steel molds with a height of 1.5±0.1 mm and internal diameter of 10.0±0.1 mm. The specimens of each WP ratio were randomly divided into two subgroups: half (n=10) were immersed for one day and the other half (n=10), were kept for 21 days in distilled water. The solubility was calculated as a percentage of the weight loss. To measure microhardness, a total of 30 samples were prepared (10 per each ratio, n=10). The mixtures were transferred to metallic cylindrical molds with internal dimensions of 6±0.1 mm height and 4±0.1 mm diameters. After 4 days the specimens were subjected to Vicker's test. The data were analyzed using two-way ANOVA and post-hoc Tukey’s tests at a significance level of 0.05. The 0.33 WP ratio showed significantly greater microhardness value (25.98±2.77) compared to 0.4 and 0.5 proportions (P=0.004 and P<0.001 respectively). Significant differences were observed between water solubility values of different WP ratios at both time intervals (P<0.001). At both time intervals, 0.33 and 0.5 WP ratios exhibited the lowest and highest solubility, respectively. According to the results of this in vitro study, higher WP ratios result in lower microhardness and higher water solubility of the CEM cement. Therefore, the 0.33 WP ratio would be the ideal proportion.

This study evaluated the effect of propylene glycol (PG) on the push-out bond strength of calcium-enriched mixture (CEM) cement compared to mineral trioxide aggregate (MTA). Methods and Materials: The lumens of two hundred 2±0.2 mm-thick root sections from human extracted teeth were prepared to achieve a diameter of 1.3 mm. The samples were then allocated into eight groups of 25 on the basis of the materials used (MTA or CEM cement) and different proportions of PG (0%, 20%, 505, and 100%). In each group, 0.4 mL of the liquid was mixed with 1 g MTA or CEM cement. After incubation, the push-out strength of the samples was measured using a universal testing machine. Data were analyzed using the two-way ANOVA followed by one-way ANOVA and student’s t-test. The MTA group showed significantly higher bond strength in comparison with CEM group (P≤0.001). Also 100% and 20% PG increased the bond strength of MTA (P≤0.001). For CEM cement, 100% and 50% PG decreased the bond strength (P≤0.001). This in vitro study demonstrated that while PG increased the push-out bond strength of MTA, it is not recommended for mixing with CEM cement.

Calcium-enriched Mixture (CEM) cement is an endodontic reparative material available in the form of powder and liquid. The purpose of this in vitro study was to determine the effect of different water-to-powder (WP) proportions on the compressive strength (CS) of the cement.
Method Materials and: One gram of CEM cement powder was mixed with either 0.33 g, 0.4 g or 0.5 g CEM liquid. The mixture was transferred to metallic cylindrical molds (n=10) with internal dimensions of 6±0.1 mm height and 4 ±0.1 mm diameter. After 4 days, the specimens were subjected to compressive strength tests using a universal testing machine. The data were analyzed by One-way ANOVA and Tukey’s tests at a significance level of 0.05.
Statically significant difference was found among experimental groups (P According to the results, higher WP ratios results in lower CS of the cement.

the aim of the present study was to evaluate the influence of propylene glycol (PG) on the flowability, microhardness, pH and calcium ion release of calcium-enriched mixture (CEM).
Methods and Materials: CEM cement was mixed with different proportions of PG, as follows: group 1,100% CEM liquid (CL); group 2, 100% PG; group 3, 50% PG and group 4, 20% PG. For assessment of flowability, methodology of ADA Specification No. 57 was applied. For measuring microhardness, 80 cylindrical molds (6×4 mm) were filled with CEM cement and divided into 2 subgroups (4, 21 days) and tested using Vickers Test. Data were analyzed using the one-way ANOVA test and Tukey’s post hoc and student’s t test. In order to check pH and calcium release, the mixed cements were placed in cylindrical molds (5×2 mm). After 3, 24, 72 and 168 h, pH determined by a pH meter and the calcium release was measured by an atomic absorption spectrophotometer. Data were analyzed using the repeated measure ANOVA, one way ANOVA test and Tuckey’s post hoc test.
The present study showed that the presence of PG did not affect the flowability. With the elapse of time, microhardness was significantly increased in all groups except CL group. Regardless of time, samples with 50% PG showed the lowest pH value which was significantly different from other groups (P addition of PG did not have any positive or negative effect on the flowability and pH of CEM cement but increased its microhardness in long term. Calcium ion release also increased in the concentration of 20% and 100%.

The aim of the present study was to evaluate and compare the compressive strength (CS) of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement when mixed with propylene glycol (PG).
Methods and Materials: Twenty four custom-made split molds with 5 holes in each were prepared. Molds were allocated into eight groups (n=15 holes) as follows: Groups 1,5: CEM and MTA mixed with PG (100%), Groups 2,6: CEM and MTA mixed with PG (20% )ࡃ or MTA liquid (80%) respectively, Groups 3,7: CEM and MTA mixed with PG (50% )ࡃ or MTA liquid (50% ) respectively, Groups 4,8: CEM and MTA mixed with CEM or MTA liquid respectively as control groups. All specimens were kept in 37°C in an incubator and the compressive strength was evaluated after 7 days. Data were analyzed using the Kruskal Wallis and Dunne tests. The level of significance was set at 0.05.
In all concentration of PG, MTA samples showed better results than CEM cement. In CEM samples, adding 20% PG could significantly increase the compressive strength in comparison with control group and 100% PG (P=0.047 and P=0.011, respectively). In MTA samples, adding 100% and 50% PG significantly increased the compressive strength of the cement in comparison with control group (P=0.037 and, P=0.005, respectively).
Considering the limitations of the present study, appropriate concentration of PG could improve the CS of MTA and CEM cement.

Propylene glycol (PG) improves the handling, physical, and chemical properties of mineral trioxide aggregate (MTA). This study aimed to evaluate the effect of PG on the sealing ability of MTA and calcium-enriched mixture (CEM) apical barriers.
Methods and Materials: A total of 70 extracted human maxillary single-rooted teeth were prepared using ProTaper rotary system. The apical 3 mm of the root tips were resected and the root canals were enlarged with Peeso reamers up to #4, to create open apex teeth. The teeth were then randomly divided into four experimental (n=15) and two control (n=5) groups. Group1: MTA MTA liquid, group2; MTA㄰ liquid (80%) PG (20%), group3; CEMࡃ liquid, group4; CEM liquid (80%) PG (20%). Cements were mixed with their respective mixing agents and a 4-mm thick apical plug was fabricated. The microleakage was measured on day 1, 3, 7 and 21 using a fluid filtration technique. The repeated measures ANOVA and Sidak test were used to analyze the data.
All experimental groups demonstrated various amounts of microleakage. No significant difference was found between MTA and CEM cement (P=0.193), regardless of time and liquid components. There was no significant difference was observed between liquids (P=0.312) in all time intervals. The rate of microleakage decreased over time and a significant differences was observed between all intervals (P PG demonstrated neither a positive nor a negative effect on the sealing ability of Angelus MTA and CEM cement.

Statement of the Problem: Correct proportioning and mixing are essential to ensure cements attain their optimum physical properties.
The aim of this experimental study was to evaluate the influence of various mixing techniques including manual, mechanical mixing, and ultrasonic vibration on push-out bond strength of calcium enriched mixture (CEM).
Ninety 2-mm-thick dentin disks were prepared from single-rooted human teeth and filled with CEM mixed with manual, trituration, or ultrasonic methods. Push-out bond strength values of the specimens were measured by a universal testing machine after 3 and 21 days. The samples were then examined under a stereomicroscope at 40× magnification to determine the nature of bond failure. Data were analyzed by Kruskal-Wallis and Mann-Whitney test. (p The highest (7.59 MPa) and lowest (4.01 MPa) bond strength values were recorded in conventional method (after 21 days) and trituration method (after 3 days), respectively. There was no statistically significant difference between the three techniques in 3 and 21 days.
According to the results, various mixing techniques had no effect on the push-out bond strength of CEM cement.

Statement of Problem: Adhesion to root canal dentin is one of the necessary characteristics of endodontic sealers. MTA Fillapex (Angelus, Londria, PR, Brazil) is one of the recently introduced MTA-based sealer. Only a limited number of studies have evaluated the bonding of this sealer to the dentin, with conflicting results. The purpose of this study was to evaluate the bond strength of MTA Fillapex sealer) to root canal dentin compared to an epoxy resinbased sealer (AH26 sealer). Twenty root blocks (6mm length) were acquired from the middle part of the extracted single-rooted central or lateral maxillary incisor roots and their lumens were enlarged to achieve a diameter of 1.3 mm. MTA Fillapex and AH26 were placed in the lumens of root blocks (n = 10). The specimens were kept in an incubator for 7 days, the roots were sectioned perpendicular to their long axis to achieve slices with thickness of 1 mm and the push-out test was carried out by a universal testing machine. The mean value of bond strength was 1.84 ± 0.7 Mpa for AH26 and 0.19 ± 0.1 Mpa for MTA Fillapex. The difference between the two groups was statistically significant (p < 0.001). With in the limitation of this study, AH 26 showed significantly higher bond strength in comparison to MTA Fillapex.

Statement of Problem: The pH of the human abscess has been measured as low as 5.0. This low pH could potentially inhibit setting reactions, affect adhesion, or increase the solubility of root end filling materials hence affect the compressive strength. Moreover, root end filling materials might expose or even mix with lidocaine HCL during periapical surgery. The aim of this in vitro study was to evaluate the effect of acidic pH and lidocaine on the compressive strength of calcium-enriched mixture (CEM). CEM was mixed according to the manufacturer’s instructions or with lidocaine (L), and condensed into 6×4 mm split moulds. The samples were exposed to phosphate buffered saline (PBS) at pH 5 or 7.4 for 7 or 28 days. Cylindrical blocks of CEM (total number = 120 and 15 for each group) were subjected to compressive strength test using a universal testing machine. Data were analysed using three-factor analysis of variance (ANOVA). Regardless of pH and time, significant differences were not found between lidocaine groups and the groups that were mixed according to the manufacturer’s instruction (p = 0.083). For both mixing agents, regardless of time, there were no significant differences between the two pH levels (p = 0.157). Regardless of the material and pH, there was a significant increase in the compressive strength from days 7 to 28 (p 0.001). Mixtures with lidocaine and exposure to an acidic environment had no adverse effects on the compressive strength of CEM Cement.

Statement of the Problem: Insolubility is an important criterion for an ideal root-end filling material to both prevent any microleakage between the root canal and the periradicular space and provide sealing ability. Many recent studies have shown that mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) have acceptable sealing ability. The purpose of this in vitro study was to evaluate the solubility of these root-end filling materials. Forty stainless steel ring moulds with an internal diameter of 10±1 mm and a height of 2±0.1 mm were selected. Samples of MTA and CEM were mixed according to the manufacturer’s instructions and inserted into the moulds. The specimens were divided into 4 experimental groups and kept in synthetic tissue fluid (STF) for 2 different time periods (7 and 28 days). The control group contained 8 empty rings. The moulds’ weights were recorded before and after immersion in STF. The changes in the weight of the samples were measured and compared using a two- way ANOVA test at a significance level of 5%. Specimens were evaluated with scanning electron microscopy (SEM) at a magnification of 500×. There was no significant difference in weight changes between MTA and CEM samples (p> 0.05).

The aim of this experimental laboratory study was to evaluate the effect of different mixing and placement techniques on compressive strength (CS) of calcium-enriched mixture (CEM) cement. Methods and Materials: CEM powder was mixed with its liquid either by hand mixing or amalgamator mixing. The mixture was loaded to cylindrical acrylic molds with 6.0±0.1 mm height and 4.0±1 mm diameter. Half of the specimens in each group were selected randomly and ultrasonic energy was applied to them for 30 sec. All samples were incubated for 7 days at 37°C. The CS test was performed by means of a universal testing machine. The data were analyzed by the two-way analysis of variance (ANOVA) and Tukey’s post hoc tests. The level of significance was set at 0.05. The maximum CS was seen in the amalgamator-mixed samples that did not receive ultrasonic agitation. The CS value of amalgamator-mixed samples was significantly higher than manually-mixed ones (P=0.003). Ultrasonic vibration did not change the CS of specimens. According to the results, mixing with amalgamator increases the CS of CEM cement, while ultrasonic vibration had no positive effect.

Statement of the Problem: In clinical situations, Calcium-Enriched Mixture (CEM) comes into direct contact or even mixes with blood during or after placement. The aim of this study was to evaluate the effect of blood contamination on the compressive strength of CEM. Three experimental groups were included in this study. In the first group, CEM was mixed with distilled water and was exposed to normal saline (control group). In the second group, CEM cement was mixed with distilled water and then was exposed to blood. In the third group, CEM was mixed with and exposed to blood. Nine custom-made two-part split Plexiglas molds with five holes were used to form CEM samples for compressive strength testing (15 samples in each group). After 7 days of incubation, compressive bond strength testing was performed using a universal testing machine. Data were statistically analyzed using the Mann–Whitney U test with a significance level of p< 0.05. Nine samples from group 3 were fractured during removal from the molds; the other six blocks had some cracks on their surfaces. Therefore, a compressive strength measurement was not obtainable for this group. No statistically significant difference was found between groups 1 and 2 (p> 0.05). It can be concluded that exposure to blood does not adversely affect the compressive strength of CEM, but incorporation of blood makes the cement very brittle.

The aim of this study was to evaluate the compressive strength of calcium-enriched mixture (CEM) cement in contact with acidic, neutral and alkaline pH values. Methods and Materials: The cement was mixed according to the manufacturer’s instructions, it was then condensed into fourteen split molds with five 4×6 mm holes. The specimens were randomly divided into 7 groups (n=10) and were then exposed to environments with pH values of 4.4, 5.4, 6.4, 7.4, 8.4, 9.4 and 10.4 in an incubator at 37° C for 4 days. After removing the samples from the molds, cement pellets were compressed in a universal testing machine. The exact forces required for breaking of the samples were recorded. The data were analyzed with the Kruskal-Wallis and Dunn tests for individual and pairwise comparisons, respectively. The level of significance was set at 0.05. The greatest (48.59±10.36) and the lowest (9.67±3.16) mean compressive strength values were observed after exposure to pH value of 9.4 and 7.4, respectively. Alkaline environment significantly increased the compressive strength of CEM cement compared to the control group. There was no significant difference between the pH values of 9.4 and 10.4 but significant differences were found between pH values of 9.4, 8.4 and 7.4. The acidic environment showed better results than the neutral environment, although the difference was not significant for the pH value of 6.4. Alkaline pH also showed significantly better results than acidic and neutral pH. The compressive strength of CEM cement improved in the presence of acidic and alkaline environments but alkaline environment showed the best results.

The aim of this in vitro study was to evaluate the effect of 2% chlorhexidine (CHX) on the push-out bond strength (BS) of calcium-enriched mixture (CEM) cement. Methods and Materials: Root-dentin slices from 60 single-rooted human teeth with the lumen diameter of 1.3 mm were used. The samples were randomly divided into 4 groups (n=15), and their lumens were filled with CEM cement mixed with either its specific provided liquid (groups 1 and 3) or 2% CHX (groups 2 and 4). The specimens were incubated at 37°C for 3 days (groups 1 and 2) and 21 days (groups 3 and 4). The push-out BS were measured using a universal testing machine. The slices were examined under a light microscope at 40× magnification to determine the nature of bond failure. The data were analyzed using the two-way ANOVA. For subgroup analysis the student t-test was applied. The level of significance was set at 0.05. After three days, there was no significant difference between groups 1 and 2 (P=0.892). In the 21-day specimens the BS in group 3 (CEM) was significantly greater than group 4 (CEM+CHX) (P=0.009). There was no significant difference in BS between 3 and 21-day samples in groups 2 and 4 (CEM+CHX) (P=0.44). However, the mean BS after 21 days was significantly greater compared to 3-day samples in groups 1 and 3 (P=0.015). The bond failure in all groups was predominantly of cohesive type. Mixing of CEM with 2% CHX had an adversely affected the bond strength of this cement.

This laboratory study was performed to evaluate the effect of different acidic pH values on the push-out bond strength of calcium-enriched mixture (CEM) cement. Methods and Materials: Forty-eight root dentin slices were obtained from freshly extracted single rooted human teeth and their lumen were instrumented to achieve a diameter of 1.3 mm. Then, CEM cement was mixed according to manufacturers’ instruction and placed in the lumens with minimal pressure. The specimens were randomly divided into four groups (n=12) which were wrapped in pieces of gauze soaked in either synthetic tissue fluid (STF) (pH=7.4) or butyric acid which was buffered at pH values of 4.4, 5.4 and 6.4. They were then incubated for 4 days at 37°C. The push-out test was performed by means of the universal testing machine. Specimens were then examined under a digital light microscope at 20× magnification to determine the nature of the bond failure. The data were analyzed using the Kruskal-Wallis test followed by Dunn’s test for pair-wise comparisons. The highest push-out bond strength (10.19±4.39) was seen in the pH level of 6.4, which was significantly different from the other groups (P<0.05). The values decreased to 2.42±2.25 MPa after exposure to pH value of 4.4. Lower pH value of highly acidic environments (pH=4.4), adversely affects the force needed for displacement of CEM cement; while in higher pH values (pH=6.4) the bond-strength was not affected. CEM cement is recommended in clinical situations where exposure to acidic environment is unavoidable.

Trioxide Aggregate (MTA) has been widely used in root canal therapy. MTA has been mixed with chlorhexidine to increase its antimicrobial effect.. The aim of this study was to evaluate the effect of chlorhexidine (2%) on push-out bond strength of Mineral Trioxide Aggregate (MTA).. Sixty dentin disks with a thickness of 1.5 ± 0.2 mm and lumen size of 1.3 mm were prepared. Dentin disks were randomly divided into four groups (n = 15), and their lumens were filled with MTA mixed with distilled water (groups 1 and 3) or with chlorhexidine 2% (groups 2 and 4). Specimens were incubated at 37°C for 3 days (groups 1 and 2) or 21 days (groups 3 and 4). Bond strengths of the MTA-treated dentin surfaces were evaluated using a universal testing machine, and bond failure on the disks was examined by light microscope. Data was analyzed using Kruskal-Wallis H test (P = 0.976).. There were no statistically significant differences between all the experimental groups. The mode of bond failure was predominantly mixed for distilled water groups and cohesive for CHX groups.. This study suggested that chlorhexidine had no negative effect on the bond strengths of MTA-treated dentin..

The purpose of this study was to determine the in vitro antimicrobial ability against Entrococcus (E.) faecalis of triple antibiotic paste and its components compared with calcium hydroxide mixtures. An agar well diffusion assay and MIC method were used to determine the efficacy of the experimental medicaments in removing E. faecalis. Medicaments were divided into 9 groups; triple antibiotic powder with saline or chlorhexidine, metronidazole, ciprofloxacin, minocycline antibiotics were also separately tested (with normal saline), and Ca(OH)2 (plus normal saline or 2% chlorhexidine). These medicaments were evaluated at four concentrations of 25, 50, 100 and 200 µg per mL in an agar well diffusion test. The diameters of the growth inhibition zones for each group were recorded and compared. The minimum inhibitory concentrations (MIC) of tested medicaments that are required to kill E. faecalis were also determined. The differences between groups were analyzed by Kruskal-Wallis and Mann-Whitney U tests. The largest inhibition zones were observed for the triple antibiotic mixture/saline, triple antibiotic mixture/2% chlorhexidine and minocycline/saline, and the smallest for Ca(OH)2/saline, Ca(OH)2/2% chlorhexidine. Concentration increases produced greater antibacterial effects in all groups. The MIC determination method showed similar results. The results suggest that the triple antibiotic paste with either 2% chlorhexidine or normal saline would be the preferred medicament against E. faecalis and, among its three components, minocycline has the greatest antibacterial effect.

The crown-root fracture is a common tooth injury which compromises the biological width and need proper endodontic and prosthodontic treatment to achieve acceptable clinical outcome. This case report describes clinical management of crown-root fracture in maxillary central incisors which was successfully treated by forceps eruption with 180˚ rotation to restore the biological width. The patient was followed-up for 18 months. Clinical and radiographic evaluation showed acceptable results, the replanted teeth have normal function and no obvious inflammatory root resorption was seen on radiographic examination.