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Showing 7 results for shafiee
A comparative survey on the increased fracture resistance of amalgam restored teeth using three types of Glass Ionomer as adhesive liners
F. Shafiee , Z. Borhan Haghighi ,
Volume 17, Issue 3 (7 2004)
Abstract

Statement of Problem: Because dental amalgam does not adhere to tooth structure, using adhesive cements in amalgam-bonded restorations have been increased.

Purpose: The goal of this in-vitro study was to compare the effects of three types of glass ionomer as adhesive liners as well as varnish liner in increasing fracture resistance of teeth restored with amalgam.

Materials and Methods: Seventy extracted human maxillary premolars were selected and MOD cavities were prepared on them excluding ten intact teeth as positive control group and ten cavity prepared teeth without restoration as negative control group. All the prepared teeth were then restored with spherical amalgam (gs.80) with one of the following liners silver alloy glass ionomer liner, conventional glass ionomer liner, varnish liner, resin-modified glass ionomer and resin-modified glass ionomer with delayed light curing. The teeth were stored in 37C distilled water for 7 days and were then loaded under compressive strength using an Instron testing machine. The force required to fracture teeth were recorded and the data were analyzed statistically using ANOVA and Tukey HSD tests.

Results: Statistically significant differences were observed in fracture resistance between restored and non-restored samples. Comparisons between groups attributed significant effects to resin-modified glass ionomer in increasing fracture resistance of amalgam restored teeth (P<0.05). In most specimens, one cusp was separated from tooth structure whereas amalgam remained bonded to the intact cusp. Conclusion: According to these findings, resin-modified glass ionomer put a statistically significant effect in fracture resistance of amalgam-restored teeth.


Composite shear bond strength to dry and wet enamel with three self-etch adhesives
F. Shafiee , M. Motamedi , S. Zargham ,
Volume 18, Issue 4 (5 2006)
Abstract

Background and Aim: The bonding mechanisms of self etching primers, based upon the simultaneous etching and priming of dentin, simplifies the bonding technique, but the efficiency of these systems is still controversial. This study compared the shear bond strength of three self etch adhesive systems in dry and wet conditions.

Materials and Method: In this experimental study, 77 intact bovine lower incisors with flat 600 grit sanded enamel surface were fixed in acrylic molds and divided into 7 groups, of 11 teeth. The enamel surfaces were treated according to a special procedure as follows: Group 1: Prompt L-Pop (PLP) in dry condition, Group 2: Prompt L-Pop in wet condition, Group 3: Clearfield SE Bond (CSEB) in dry condition, Group 4: Clearfield SE Bond in wet condition, Group 5: iBond (iB) in dry condition, Group 6: iBond in wet condition, Group 7: Margin Bond (Control) in dry condition. Surfaces were air dried for ten seconds, or blot dried in wet condition. Composite resin was bonded on the enamel and built up by applying a cylindric teflon split mold (4 mm height 2mm diameter). After 24 hours storage in dionized water at room temperature, all specimens were thermocycled and shear bond test was employed by a universal testing machine (Instron) with a cross-head speed of 1mm/min. The shear bond strength was recorded in MPa and data were analyzed with ANOVA and Scheffe statistical tests. P<0.05 was considered as statistically significant. The mode of failure was examined under a stereomicroscope.

Results: 1- Shear bond strength of CSEB in dry condition (21.5 ± 4.8 MPa) was significantly higher than PLP and iB groups (p<0.0001). 2- Shear bond strength of iB and PLP groups in dry condition (9.60 ± 2.2, 9.49 ± 3 MPa) were significantly lower than CSEB and control (2.99 ± 5.1 MPa) (P<0.0001). 3- There was no significant difference between PLP and iB groups in dry condition (P=1). 4- Shear bond strength of CSEB in wet condition (21.8 ± 3 MPa) was significantly higher than PLP and iB groups (P=0.0). 5- Shear bond strength of CSEB (10.8 ± 3 MPa) and PLP (10.6 ± 4 MPa) in wet condition were significantly lower than CSEB and Control groups (P=0.0). 6- There was no significant difference between PLP and iB groups in wet condition (P=0.99). 7- Shear bond strength of the three adhesives had no significant difference in dry and wet conditions (PLP: P= 0.53, CSEB: P= 0.84, iB: P= 0.53). The mode of failure in two groups of PLP and two groups of iB was predominantly in the adhesive bond and in the two groups of CSEB, mixed failure (adhesive with cohesive in composite) was predominantly observed.

Conclusion: CSEB had higher while iB and PLP showed lower bond strength to ground enamel. The three self-etch adhesives in this study did not show technique sensitivity to wet and dry enamel.


A comparison between the effect of zirconia-coated FRC and glass fiber posts on the fracture resistance of endodontically treated teeth
Ezatollah Jalalian, Mona Sadegh, Rana Mohamadi, Reihane Aghajani, Elnaz Shafiee,
Volume 27, Issue 1 (4-2014)
Abstract

  Background and Aims : The root fracture resistance of endodontically treated teeth depends on the types of posts. The aim of this study was to compare the effect of two types of bonded non-metallic posts with different elasticity modulus on the fracture resistance of endodontically treated teeth under compressive loads.

  Materials and Methods: In this in vitro experimental study, 20 fresh extracted mandibular premolars were selected and sectioned adjacent to the CEJ and then were endodontically treated. The specimens were randomly divided into two groups (n=10). After post space preparations, the fiber RTD Light posts (R.T.D, France) and zirconia coated fiber posts (ICE light, Danville) were cemented into the root canals. Composite resin (Lumiglass R.T.D, France) cores were built up. Aluminium foil was used to mimic the PDL, and the specimens were embedded in acrylic resin and tested in a Universal Testing Machine. A compressive load was applied at a 90 degree angle until fracture at a crosshead speed of 1mm/min. Data were analyzed using one-way ANOVA and T test .

  Results: The mean fracture resistance of R.T.D group was (1083.11 ± 156.74 (N)) and the mean of ICE light group was (865.18 ± 106.24 (N)). The highest mean fracture resistance was observed in RTD fiberglass and a statistically significant difference was observed between the two groups (P<0.001).

  Conclusion: FRC posts with zirconia coating due to unfavorable fractures of the teeth should be used with caution, and thus, fiber posts are preferred.


Comparing color coordinates of three ceramic systems with corresponding shade guide
Farzaneh Farid, Pedram Etemadi, Farhad Shafiee,
Volume 30, Issue 2 (8-2017)
Abstract

Background and Aims: Increase of esthetic demands among dental patients has led to development and wide spread use of tooth colored ceramic systems for fabricating fixed restorations. However, they do not have same capability of matching the target color. The aim of this study was to compare the color coordinates of three widely used systems with A2 tab from a Vita Lumin Classic shade guide.
Materials and Methods: In this study, three ceramic systems were tested. The metal-ceramic(MCR) with 0.5 mm core and 1 mm Ceramco lll veneering layer; the all ceramic (CE) with 0.5 mm Cercon core and 1 mm Cercon Ceram veneering layer, and the all porcelain (VM7) with 1.5 mm Vita VM7. For each system, 15 disks (1.5mm×10mm) were made in Vita A2 shade. L*a*b* coordinates of the samples were measured by spectrophotometer and the color difference with Vita A2 shade was calculated. The data were analyzed using one way ANOVA and multiple Tukey tests.
Results: The color coordinates of the target shade was L*=72.45, a=1.59 and b*=14.11. The mean L*a*b* values for MCR were 72.61±0.38, 2.88±0.24, 15.51±0.64, for CE were 76.42±0.46, 2.77±0.14, 17.51±0.61, and for VM7 were 75.13±0.6, 2.15±0.19, 17.9±0.61, respectively. The difference between coordinates of each system with target shade was significant. Only for MCR group, ΔE was in acceptable range (1.98). For CE (Δ=5.38) and VM7 (Δ=4.72) groups, the difference was unacceptable.
Conclusion: Under the condition of this study, the metal-ceramic system had the best and acceptable match to the target shade.
 

Comparison of dentinal tubules closure under the effect of carbonated nano structural hydroxyapatite toothpaste produced inside the country with fluoride toothpaste
Rahelesadat Mirseifi Nejad Naini, Alireza Daneshkazemi, Fahime Shafiee,
Volume 31, Issue 2 (9-2018)
Abstract
Background and Aims: Increased tooth sensitivity is a common dental problem. One of the mechanisms of dentin hypersensitivity treatment is blocking dentinal tubules. The aim of this study was to compare the average closing dentinal tubules affected by carbonated Nano-hydroxyapatite and fluoride toothpaste using scanning electron microscope (SEM).
Materials and Methods: The enamel of gingival buccal crown surfaces of 42 sound maxillary premolars teeth were removed until the dentin surfaces were exposed. The dentine specimens of 3×3 mm were prepared. The specimens were washed by distilled water after etching and randomly divided into 6 groups. 3 groups were interfered with the carbonated nano-hydroxyapatite toothpaste and the other three groups interfered with Colgate toothpaste in 3, 7 and 14 days. The samples were examined by SEM to check the status of dentinal tubules. Then, they were evaluated by two researchers according to the Hulsmann index. Data were analyzed by using SPSS23 software and Kruskal-Wallis statistical test. The significance level of 0.05 was considered.
Results: The amount of dentinal tubules closure by the two toothpastes was significantly different. This difference was higher in the hydroxyapatite toothpaste than fluoride which were (P=0.024, 0.004 and 0.000), respectively. There were no significant differences among the groups in 3,7 and 14 days (P=0.230, 0.069, 0.537).
Conclusion: The toothpaste containing carbonated nano structural hydroxyapatite was more successful in closing dentinal tubules than Colgate toothpaste in short period of time.

Evaluating the knowledge of elementary school health teachers of Sanandaj about traumatic dental injuries in year 2017-2018
Maliheh Karame, Masoud Moradi, Farank Shafiee,
Volume 31, Issue 4 (1-2019)
Abstract
Background and Aims: Trauma to primary and permanent teeth caused post-traumatic complications affecting the health of teeth and led to specific problems in treatment. As prognosis of trauma has closed correlation with immediate and correct management after occurrence of the incident and the health educators are the first people in contact with children in this places, their awareness of how to deal with these injuries plays an important role in prevention and treatment. This study aimed to evaluate the knowledge of health educators in confrontation with dental injuries in primary schools of Sanandaj in 2018.
Materials and Methods: In this cross-sectional study, all of fifty-nine health teachers in primary schools of Sanandaj were identified after referring to education centre. The questionnaires were provided to the school health teachers after referring to schools and after completing questionnaires, collected data were analyzed. In order to test the research hypotheses, Multiple regression, Non-parametric tests of spearman correlation coefficient, Mann-Whitney and kruskal-wallis were utilized using SPSS software version 20.
Results: The mean knowledge score of fifty-nine health educators was 14.02±3.41 and knowledge score of females was higher. There was no significant statistical correlation between knowledge score, age,
work experience and education level (P>0.05). In this study, the knowledge score of experienced teachers in confrontation with injured persons and health educators who attended related training courses, was higher than others but this difference was not statistically significant (P>0.05).
Conclusion: The results indicated inadequate knowledge regarding emergency management of dental trauma. Thus strategies to improve the teachers’ knowledge about dental trauma can positively influence their knowledge and attitudes toward emergency management of dental trauma.

Assessment of oral health and quality of life in hemophilia and thalassemia major patients
Sahar Mohamadi, Borhan Moradveisi, Mohamad Aziz Rasouli, Faranak Shafiee,
Volume 33, Issue 3 (10-2020)
Abstract
Background and Aims: The chronic blood disorders could have negative effects on various fields of patient’s quality of life. The aim of this study was to evaluate the relationship between the quality of life and oral health in major thalassemia and hemophilia patients.
Materials and Methods: This cross- sectional study was performed in 1398 on 56 hemophilia patients and 35 thalassemia major patients over 15 years of age. All the subjects were examined clinically to determine DMFT and CPITN, then the subjects completed OHIP-14, xerostomia, SF36 questionnaire. Data was analyzed with T-Test, ANOVA and Chi-square using Stata14.
Results: TThe mean age of hemophilia and beta-thalassemia patients was 32.3 and 26.2, the mean DMFT index was 8.75 and 7.6, and CPITN index was 2.02 and 2.26, respectively. Analysis of the components of the DMFT index showed a predominance of number of decayed teeth over filled teeth in both groups. According to the CPITN index, 19.6% and 20% of hemophilia and thalassemia patients had gingival healthy, respectively. The mean quality of life total scores in patients with hemophilia and thalassemia was 62.11 and 58.07, respectively. The mean DMFT had a significant negative relationship with the quality of life total scores in both groups (P<0.05). There was a significant relationship between different domains of quality of life and CPITN and OHIP-14 in thalassemia patients (P<0.05). Also patients with dry mouth had lower quality of life.
Conclusion: Hemophilia and thalassemia patients indicated undesirable oral health. It is necessary to improve multidimensional strategies in various fields of health care in patients.

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