Aydin Sohrabi - Academia.edu (original) (raw)

Papers by Aydin Sohrabi

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution,... more The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by t...

Photomedicine and Laser Surgery, 2014

As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms ... more As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms will become more resistant to commonly used antibacterial irrigants. Photodynamic therapy (PDT) has been used to kill resistant bacteria organized in a biofilm. This study aimed to investigate the antimicrobial effectiveness of 1% sodium hypochlorite (NaOCl), 2.5% NaOCl, and PDT on E. faecalis biofilm at different stages of development. In this study 4-, 6-, and 8-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS), PDT, or 1% and 2.5% NaOCl. Dentin chip suspensions were used for colony forming units (CFU) counting to estimate remaining E. faecalis counts. PDT and 2.5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 81.88%, 85.73%, and 78.62% reductions of bacterial counts in 4-, 6-, and 8-week-old biofilms, respectively, which was significantly more than PBS. The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival and residual bacteria increase with biofilm aging. PDT and the 2.5% NaOCl solution were equally efficient in completely eliminating E. faecalis biofilms at all three stages.

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandib... more The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences...

Iranian endodontic journal, 2016

The aim of the present in vitro study was to compare the accuracy of cone-beam computed tomograph... more The aim of the present in vitro study was to compare the accuracy of cone-beam computed tomography (CBCT) in determining root canal morphology of mandibular first molars in comparison with staining and clearing technique. CBCT images were taken from 96 extracted human mandibular first molars and the teeth were then evaluated based on Vertucci's classification to determine the root canal morphology. Afterwards, access cavities were prepared and India ink was injected into the canals with an insulin syringe. The teeth were demineralized with 5% nitric acid. Finally, the cleared teeth were evaluated under a magnifying glass at 5× magnification to determine the root canal morphology. Data were analyzed using the SPSS software. The Fisher's exact test assessed the differences between the mesial and distal canals and the Cohen's kappa test was used to assess the level of agreement between the methods. Statistical significance was defined at 0.05. The Kappa coefficient for agre...

12 Th International Congress of Iranian Academy of Restorative Dentistry 24 26 October 2012 Tabriz Iran, Oct 23, 2012

Molar incisor hypomineralization (MIH) is defined as the developmentally-derived dental defect th... more Molar incisor hypomineralization (MIH) is defined as the developmentally-derived dental defect that involves 1 to 4 permanent first molars, frequently associated with similarly affected permanent incisors. The prevalence of MIH ranges from 3.6-25%. Several etiological factors are mentioned as the cause of the defect including prenatal, perinatal and childhood medical conditions that affect the developing enamel, while an underlying genetic predisposition could not be excluded. MIH presents as demarcated enamel opacities of different color in the affected teeth that occasionally undergo post eruptive breakdown due to soft and porous enamel, resulting in atypical cavities or even to complete coronal distortion. Accordingly the defect reveals serious clinical management problems attracting the attention of the dental profession. Children with MIH receive much more dental treatment than unaffected children. Affected molars usually require extensive treatment and might create serious problems for both patient and clinician, as they can frequently be difficult to anaesthetize and to restore adequately. Children at risk should be monitored very carefully during the period of eruption of their first permanent molars. Intensive individually prescribed preventive programs may postpone the initiation of the actual restorative treatment and reduce in long-term patient's discomfort. Treatment planning should consider the long-term prognosis of these teeth. Advances in dental materials have provided clinical solutions in cases that were regarded as unrestorable in the past. In this review we would have a look at etiology, clinical presentation and treatment options of hypomineralized molar and incisor teeth. molar, incisor, hypomineralization Presentation: Poster

12 Th International Congress of Iranian Academy of Restorative Dentistry 24 26 October 2012 Tabriz Iran, Oct 23, 2012

Several clinical studies have confirmed the susceptibility of patients undergoing orthodontic the... more Several clinical studies have confirmed the susceptibility of patients undergoing orthodontic therapy to dental caries. The incidence of decalcification following a course of fixed appliance therapy that lasts approximately 2 years, has been reported to be as high as 50%. The obvious degree of iatrogenic enamel damage during orthodontic treatment suggests the need for preventive programs. Several preventative methods have been applied to overcome the enamel demineralization problem during orthodontic treatment. Two approaches have been proposed in an attempt to reduce potential detrimental enamel changes during orthodontic therapy. The first approach is aimed at reducing acid solubility by the application of topical fluoride before, during and after treatment. The second approach is to protect the enamel surface by using different materials and providing a protective coating.Ozone is one of the most powerful antimicrobial agents that is currently used in medicine or dentistry. Dental caries is caused by an ecological niche of caries producing organisms. Thus it is not surprising that eliminating these organisms provides tremendous clinical and long term preventive advantages for patients. Recently, a number of studies have been undertaken on the effects of ozone on treating dental caries and the reduction of oral microorganisms. Ozone gas application and ozonated water were found to be capable of reducing the number of Ms and streptococcus sobrinus. In this paper we are going to discuss about advantages and disadvantages of ozone therapy on prevention and also treatment of white spot lesions during orthodontic treatments. prevention, white spot lesion, ozone, orthodontics Presentation: Poster

Photomedicine and Laser Surgery, 2016

Since there is no standard method for rebonding loose ceramic brackets, the aim of this study was... more Since there is no standard method for rebonding loose ceramic brackets, the aim of this study was to evaluate the possibility of using Er,Cr:YSGG laser to eliminate the remaining composite materials from the base of ceramic brackets and to compare the bond strength of rebonded brackets with the new ones. Sixty-two extracted human premolars were mounted in acrylic cylinders. Thirty-one ceramic brackets were bonded, and shear bond strength was tested using Hounsfield testing machine. The remnants of the bonding material were removed from the bases of brackets using Er,Cr:YSGG laser. These brackets were rebonded to 31 fresh teeth and again shear bond strength was measured. Pattern of debonding was assessed in both cases under a stereomicroscope and graded according to ARI index. Data were analyzed with independent t-test and Fisher's exact test. Mean shear bond strength of the bond and rebond groups was 12.29 ± 5.46 and 10.58 ± 5.16 MPa, respectively. There were no significant differences between the two groups (p = 0.21). Pattern of bond failure was not statistically different between the two groups. Er,Cr:YSGG laser was effective in removing the remnants of bonding material from the base of ceramic brackets without any interference with the ceramic base itself, demonstrating that it might be a suitable method for rebonding ceramic brackets.

The Journal of Contemporary Dental Practice, 2009

The aim of the present study was to investigate the prevalence and distribution according to vari... more The aim of the present study was to investigate the prevalence and distribution according to various arch length conditions of lingually erupted mandibular permanent incisors and the effect of space condition on this phenomenon with long-term follow-up of these teeth. A total of 105 children aged 5-7.5 years with one or more permanent mandibular incisors erupting lingual to the corresponding primary incisors were included in the study. A space analysis was performed. The subjects were divided into six groups according to various space conditions. The subjects were followed for 2 years. In this study the prevalence of lingual eruption was 18.4%. Eighty-three point seven percent of the subjects had either equivalent space, mild space excess, or a space deficiency (not more than 3 mm). No relationship was found between groups and clinical outcomes (P>.05). Follow up of the main three groups (according to the space analysis results) revealed in the adequate space group 75% of the children lost their primary incisors without any intervention. Similar outcomes occurred in 85.7% and 57.14% of cases in the mild space excess and space deficiency groups, respectively. Considering the three main groups combined, equivalent space, mild space excess, and mild space deficiency, 70.45% of children lost their primary incisors without any intervention and 14.8% needed primary incisor extraction (17.4%, 14.3%, and 10.7% in each group, respectively). There was no predisposition toward a space deficiency or excess found in these subjects so the wait-and-see policy versus early extraction can be considered for lingually erupting permanent mandibular incisors. Lingual eruption of mandibular incisors is a common clinical problem in the early mixed dentition period that is a source of discomfort for parents of patients with this condition. The present study provides a unique insight into the prevalence of the problem as well as the clinical decisions such as favoring retention of primary incisors as long as possible, the extraction of these primary teeth, placement of lower lingual holding arches, or referral for comprehensive orthodontic treatment. These types of data should not be regarded as standards but as illustrative of several key factors that are still not well-understood or which are still ignored.

Iranian Endodontic Journal, 2014

Article Type: Original Article Introduction: The aim of this in vitro study was to evaluate the e... more Article Type: Original Article Introduction: The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Methods and Materials: Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by the Kruskal-Wallis and Mann-Whitney tests. Results: Two-by-two comparisons of the groups revealed no significant differences in terms of smear layer removal at different canal sections between the negative control group (standard regiment for smear layer removal) and 1% papain groups (P<0.05).

Iranian Journal of Orthodontics, Oct 15, 2012

Introduction: The aim of this in vitro study was to evaluate the transportation of mesiobuccal ca... more Introduction: The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Methods and Materials: Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. Results: The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tuk...

The European Journal of Orthodontics, 2015

Of the various techniques used to determine the optimum timing for growth modification treatments... more Of the various techniques used to determine the optimum timing for growth modification treatments, the cervical vertebrae maturation method has great advantages, including validity and no need for extra X-ray exposure. Recently, the reproducibility of this method has been questioned. The aim of this study was to investigate the cause of poor reproducibility of this method and to assess the reproducibility of the clinical decisions made based on it. Materials/Methods: Seventy lateral cephalograms of Iranian patients aged 9-15 years were observed twice by five experienced orthodontists. In addition to determining the developmental stage, each single parameter involved in this method was assessed in terms of inter-and intraobserver reproducibility. In order to evaluate the reproducibility of clinical decisions based on this method, cervical vertebrae maturation staging (CVMS) I and II were considered as phase 1 and CVMS IV and V were considered as phase 3. Results: By considering the clinical approach of the CVMS method, inter-observer reproducibility of this method increased from 0.48 to 0.61 (moderate to substantial) and intra-observer reproducibility enhanced from 0.72 to 0.74. Limitations: 1. Complete visualization of the first four cervical vertebrae was an inclusion criterion, which also limits the clinical application of CVMS method. 2. These results can be generalized when determining growth modification treatments solely for Class II patients. Conclusions: Difficulty in determining the morphology of C3 and C4 leads to poor reproducibility of the CVMS method. Despite this, it has acceptable reproducibility in determining the timing of functional treatment for Class II patients. Society has emphasized use of the CVMS method to assess skeletal maturation and has stated that there is no orthodontic indication for the hand and wrist radiographs (4, 5). Principally, any diagnostic test must have high sensitivity, high specificity, and predictive values. In addition, the reproducibility

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandib... more The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences...

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution,... more The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by t...

European journal of paediatric dentistry : official journal of European Academy of Paediatric Dentistry, 2012

Self-etch bonding systems have been introduced recently and have the advantage of reduced operati... more Self-etch bonding systems have been introduced recently and have the advantage of reduced operating time. Because of patient management and isolation difficulties in children, the present study aimed to evaluate microtensile bond strength of two self-etch bonding systems (AdheSE and Xeno® III) on cleaned only, ground and sandblasted enamel. Thirty intact primary molars were selected and randomly divided into two groups according to the type of bonding used (Xeno® III and AdheSE). The teeth were divided into three subgroups according to enamel surface conditioning method: prophylaxis with pumice, grinding with coarse finishing and polishing disc, and sandblasting with aluminum oxide particles. Tetric Ceram composite then was applied. Samples were sectioned coronally and axially. The interface area of dental sticks was measured and specimens were subjected to a tensile force of 0.5 mm/min until failure. Microtensile bond strength of Xeno® III-sandblasting, AdheSE-sandblasting, AdheSE-...

The journal of contemporary dental practice, 2009

The aim of the present study was to investigate the prevalence and distribution according to vari... more The aim of the present study was to investigate the prevalence and distribution according to various arch length conditions of lingually erupted mandibular permanent incisors and the effect of space condition on this phenomenon with long-term follow-up of these teeth. A total of 105 children aged 5-7.5 years with one or more permanent mandibular incisors erupting lingual to the corresponding primary incisors were included in the study. A space analysis was performed. The subjects were divided into six groups according to various space conditions. The subjects were followed for 2 years. In this study the prevalence of lingual eruption was 18.4%. Eighty-three point seven percent of the subjects had either equivalent space, mild space excess, or a space deficiency (not more than 3 mm). No relationship was found between groups and clinical outcomes (P>.05). Follow up of the main three groups (according to the space analysis results) revealed in the adequate space group 75% of the chi...

Advances in Bioscience and Clinical Medicine, 2014

Journal of dental research, dental clinics, dental prospects, 2014

Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step... more Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step self-etch adhesives on Enterococcus faecalis on days 1, 7 and 14 with the use of modified direct contact test. Materials and methods. The modified directcontact test was used to evaluate the antibacterial effect of Adper Easy One, Bond Force, Clearfil S3 Bond, Futurabond M, G-Bond, iBond and OptiBond All-in-one adhesives on Enterococcus faecalis after aging the samples in phosphate-buffered saline for one, seven and fourteen days. Data were analyzed using one-way ANOVA and post hoc Tukey tests. Aging effect of each adhesive was evaluated by paired-sample test. In this study, P<0.05 was considered significant. Results. All the tested adhesives exhibited antibacterial activity after one day and had significant differences with the positive control group (P<0.05). After one week, OptiBond All-in-one, iBond and Futurabond M exhibited significant differences in bacterial growth from ot...

Photomedicine and Laser Surgery, 2014

As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms ... more As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms will become more resistant to commonly used antibacterial irrigants. Photodynamic therapy (PDT) has been used to kill resistant bacteria organized in a biofilm. This study aimed to investigate the antimicrobial effectiveness of 1% sodium hypochlorite (NaOCl), 2.5% NaOCl, and PDT on E. faecalis biofilm at different stages of development. In this study 4-, 6-, and 8-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS), PDT, or 1% and 2.5% NaOCl. Dentin chip suspensions were used for colony forming units (CFU) counting to estimate remaining E. faecalis counts. PDT and 2.5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 81.88%, 85.73%, and 78.62% reductions of bacterial counts in 4-, 6-, and 8-week-old biofilms, respectively, which was significantly more than PBS. The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival and residual bacteria increase with biofilm aging. PDT and the 2.5% NaOCl solution were equally efficient in completely eliminating E. faecalis biofilms at all three stages.

Iranian Journal of Orthodontics, Jul 15, 2013

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution,... more The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by t...

Photomedicine and Laser Surgery, 2014

As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms ... more As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms will become more resistant to commonly used antibacterial irrigants. Photodynamic therapy (PDT) has been used to kill resistant bacteria organized in a biofilm. This study aimed to investigate the antimicrobial effectiveness of 1% sodium hypochlorite (NaOCl), 2.5% NaOCl, and PDT on E. faecalis biofilm at different stages of development. In this study 4-, 6-, and 8-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS), PDT, or 1% and 2.5% NaOCl. Dentin chip suspensions were used for colony forming units (CFU) counting to estimate remaining E. faecalis counts. PDT and 2.5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 81.88%, 85.73%, and 78.62% reductions of bacterial counts in 4-, 6-, and 8-week-old biofilms, respectively, which was significantly more than PBS. The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival and residual bacteria increase with biofilm aging. PDT and the 2.5% NaOCl solution were equally efficient in completely eliminating E. faecalis biofilms at all three stages.

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandib... more The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences...

Iranian endodontic journal, 2016

The aim of the present in vitro study was to compare the accuracy of cone-beam computed tomograph... more The aim of the present in vitro study was to compare the accuracy of cone-beam computed tomography (CBCT) in determining root canal morphology of mandibular first molars in comparison with staining and clearing technique. CBCT images were taken from 96 extracted human mandibular first molars and the teeth were then evaluated based on Vertucci's classification to determine the root canal morphology. Afterwards, access cavities were prepared and India ink was injected into the canals with an insulin syringe. The teeth were demineralized with 5% nitric acid. Finally, the cleared teeth were evaluated under a magnifying glass at 5× magnification to determine the root canal morphology. Data were analyzed using the SPSS software. The Fisher's exact test assessed the differences between the mesial and distal canals and the Cohen's kappa test was used to assess the level of agreement between the methods. Statistical significance was defined at 0.05. The Kappa coefficient for agre...

12 Th International Congress of Iranian Academy of Restorative Dentistry 24 26 October 2012 Tabriz Iran, Oct 23, 2012

Molar incisor hypomineralization (MIH) is defined as the developmentally-derived dental defect th... more Molar incisor hypomineralization (MIH) is defined as the developmentally-derived dental defect that involves 1 to 4 permanent first molars, frequently associated with similarly affected permanent incisors. The prevalence of MIH ranges from 3.6-25%. Several etiological factors are mentioned as the cause of the defect including prenatal, perinatal and childhood medical conditions that affect the developing enamel, while an underlying genetic predisposition could not be excluded. MIH presents as demarcated enamel opacities of different color in the affected teeth that occasionally undergo post eruptive breakdown due to soft and porous enamel, resulting in atypical cavities or even to complete coronal distortion. Accordingly the defect reveals serious clinical management problems attracting the attention of the dental profession. Children with MIH receive much more dental treatment than unaffected children. Affected molars usually require extensive treatment and might create serious problems for both patient and clinician, as they can frequently be difficult to anaesthetize and to restore adequately. Children at risk should be monitored very carefully during the period of eruption of their first permanent molars. Intensive individually prescribed preventive programs may postpone the initiation of the actual restorative treatment and reduce in long-term patient's discomfort. Treatment planning should consider the long-term prognosis of these teeth. Advances in dental materials have provided clinical solutions in cases that were regarded as unrestorable in the past. In this review we would have a look at etiology, clinical presentation and treatment options of hypomineralized molar and incisor teeth. molar, incisor, hypomineralization Presentation: Poster

12 Th International Congress of Iranian Academy of Restorative Dentistry 24 26 October 2012 Tabriz Iran, Oct 23, 2012

Several clinical studies have confirmed the susceptibility of patients undergoing orthodontic the... more Several clinical studies have confirmed the susceptibility of patients undergoing orthodontic therapy to dental caries. The incidence of decalcification following a course of fixed appliance therapy that lasts approximately 2 years, has been reported to be as high as 50%. The obvious degree of iatrogenic enamel damage during orthodontic treatment suggests the need for preventive programs. Several preventative methods have been applied to overcome the enamel demineralization problem during orthodontic treatment. Two approaches have been proposed in an attempt to reduce potential detrimental enamel changes during orthodontic therapy. The first approach is aimed at reducing acid solubility by the application of topical fluoride before, during and after treatment. The second approach is to protect the enamel surface by using different materials and providing a protective coating.Ozone is one of the most powerful antimicrobial agents that is currently used in medicine or dentistry. Dental caries is caused by an ecological niche of caries producing organisms. Thus it is not surprising that eliminating these organisms provides tremendous clinical and long term preventive advantages for patients. Recently, a number of studies have been undertaken on the effects of ozone on treating dental caries and the reduction of oral microorganisms. Ozone gas application and ozonated water were found to be capable of reducing the number of Ms and streptococcus sobrinus. In this paper we are going to discuss about advantages and disadvantages of ozone therapy on prevention and also treatment of white spot lesions during orthodontic treatments. prevention, white spot lesion, ozone, orthodontics Presentation: Poster

Photomedicine and Laser Surgery, 2016

Since there is no standard method for rebonding loose ceramic brackets, the aim of this study was... more Since there is no standard method for rebonding loose ceramic brackets, the aim of this study was to evaluate the possibility of using Er,Cr:YSGG laser to eliminate the remaining composite materials from the base of ceramic brackets and to compare the bond strength of rebonded brackets with the new ones. Sixty-two extracted human premolars were mounted in acrylic cylinders. Thirty-one ceramic brackets were bonded, and shear bond strength was tested using Hounsfield testing machine. The remnants of the bonding material were removed from the bases of brackets using Er,Cr:YSGG laser. These brackets were rebonded to 31 fresh teeth and again shear bond strength was measured. Pattern of debonding was assessed in both cases under a stereomicroscope and graded according to ARI index. Data were analyzed with independent t-test and Fisher&#39;s exact test. Mean shear bond strength of the bond and rebond groups was 12.29 ± 5.46 and 10.58 ± 5.16 MPa, respectively. There were no significant differences between the two groups (p = 0.21). Pattern of bond failure was not statistically different between the two groups. Er,Cr:YSGG laser was effective in removing the remnants of bonding material from the base of ceramic brackets without any interference with the ceramic base itself, demonstrating that it might be a suitable method for rebonding ceramic brackets.

The Journal of Contemporary Dental Practice, 2009

The aim of the present study was to investigate the prevalence and distribution according to vari... more The aim of the present study was to investigate the prevalence and distribution according to various arch length conditions of lingually erupted mandibular permanent incisors and the effect of space condition on this phenomenon with long-term follow-up of these teeth. A total of 105 children aged 5-7.5 years with one or more permanent mandibular incisors erupting lingual to the corresponding primary incisors were included in the study. A space analysis was performed. The subjects were divided into six groups according to various space conditions. The subjects were followed for 2 years. In this study the prevalence of lingual eruption was 18.4%. Eighty-three point seven percent of the subjects had either equivalent space, mild space excess, or a space deficiency (not more than 3 mm). No relationship was found between groups and clinical outcomes (P&amp;amp;amp;amp;gt;.05). Follow up of the main three groups (according to the space analysis results) revealed in the adequate space group 75% of the children lost their primary incisors without any intervention. Similar outcomes occurred in 85.7% and 57.14% of cases in the mild space excess and space deficiency groups, respectively. Considering the three main groups combined, equivalent space, mild space excess, and mild space deficiency, 70.45% of children lost their primary incisors without any intervention and 14.8% needed primary incisor extraction (17.4%, 14.3%, and 10.7% in each group, respectively). There was no predisposition toward a space deficiency or excess found in these subjects so the wait-and-see policy versus early extraction can be considered for lingually erupting permanent mandibular incisors. Lingual eruption of mandibular incisors is a common clinical problem in the early mixed dentition period that is a source of discomfort for parents of patients with this condition. The present study provides a unique insight into the prevalence of the problem as well as the clinical decisions such as favoring retention of primary incisors as long as possible, the extraction of these primary teeth, placement of lower lingual holding arches, or referral for comprehensive orthodontic treatment. These types of data should not be regarded as standards but as illustrative of several key factors that are still not well-understood or which are still ignored.

Iranian Endodontic Journal, 2014

Article Type: Original Article Introduction: The aim of this in vitro study was to evaluate the e... more Article Type: Original Article Introduction: The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Methods and Materials: Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by the Kruskal-Wallis and Mann-Whitney tests. Results: Two-by-two comparisons of the groups revealed no significant differences in terms of smear layer removal at different canal sections between the negative control group (standard regiment for smear layer removal) and 1% papain groups (P<0.05).

Iranian Journal of Orthodontics, Oct 15, 2012

Introduction: The aim of this in vitro study was to evaluate the transportation of mesiobuccal ca... more Introduction: The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Methods and Materials: Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. Results: The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tuk...

The European Journal of Orthodontics, 2015

Of the various techniques used to determine the optimum timing for growth modification treatments... more Of the various techniques used to determine the optimum timing for growth modification treatments, the cervical vertebrae maturation method has great advantages, including validity and no need for extra X-ray exposure. Recently, the reproducibility of this method has been questioned. The aim of this study was to investigate the cause of poor reproducibility of this method and to assess the reproducibility of the clinical decisions made based on it. Materials/Methods: Seventy lateral cephalograms of Iranian patients aged 9-15 years were observed twice by five experienced orthodontists. In addition to determining the developmental stage, each single parameter involved in this method was assessed in terms of inter-and intraobserver reproducibility. In order to evaluate the reproducibility of clinical decisions based on this method, cervical vertebrae maturation staging (CVMS) I and II were considered as phase 1 and CVMS IV and V were considered as phase 3. Results: By considering the clinical approach of the CVMS method, inter-observer reproducibility of this method increased from 0.48 to 0.61 (moderate to substantial) and intra-observer reproducibility enhanced from 0.72 to 0.74. Limitations: 1. Complete visualization of the first four cervical vertebrae was an inclusion criterion, which also limits the clinical application of CVMS method. 2. These results can be generalized when determining growth modification treatments solely for Class II patients. Conclusions: Difficulty in determining the morphology of C3 and C4 leads to poor reproducibility of the CVMS method. Despite this, it has acceptable reproducibility in determining the timing of functional treatment for Class II patients. Society has emphasized use of the CVMS method to assess skeletal maturation and has stated that there is no orthodontic indication for the hand and wrist radiographs (4, 5). Principally, any diagnostic test must have high sensitivity, high specificity, and predictive values. In addition, the reproducibility

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandib... more The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT). Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05. The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences...

Iranian endodontic journal, 2014

The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution,... more The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer. Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by t...

European journal of paediatric dentistry : official journal of European Academy of Paediatric Dentistry, 2012

Self-etch bonding systems have been introduced recently and have the advantage of reduced operati... more Self-etch bonding systems have been introduced recently and have the advantage of reduced operating time. Because of patient management and isolation difficulties in children, the present study aimed to evaluate microtensile bond strength of two self-etch bonding systems (AdheSE and Xeno® III) on cleaned only, ground and sandblasted enamel. Thirty intact primary molars were selected and randomly divided into two groups according to the type of bonding used (Xeno® III and AdheSE). The teeth were divided into three subgroups according to enamel surface conditioning method: prophylaxis with pumice, grinding with coarse finishing and polishing disc, and sandblasting with aluminum oxide particles. Tetric Ceram composite then was applied. Samples were sectioned coronally and axially. The interface area of dental sticks was measured and specimens were subjected to a tensile force of 0.5 mm/min until failure. Microtensile bond strength of Xeno® III-sandblasting, AdheSE-sandblasting, AdheSE-...

The journal of contemporary dental practice, 2009

The aim of the present study was to investigate the prevalence and distribution according to vari... more The aim of the present study was to investigate the prevalence and distribution according to various arch length conditions of lingually erupted mandibular permanent incisors and the effect of space condition on this phenomenon with long-term follow-up of these teeth. A total of 105 children aged 5-7.5 years with one or more permanent mandibular incisors erupting lingual to the corresponding primary incisors were included in the study. A space analysis was performed. The subjects were divided into six groups according to various space conditions. The subjects were followed for 2 years. In this study the prevalence of lingual eruption was 18.4%. Eighty-three point seven percent of the subjects had either equivalent space, mild space excess, or a space deficiency (not more than 3 mm). No relationship was found between groups and clinical outcomes (P>.05). Follow up of the main three groups (according to the space analysis results) revealed in the adequate space group 75% of the chi...

Advances in Bioscience and Clinical Medicine, 2014

Journal of dental research, dental clinics, dental prospects, 2014

Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step... more Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step self-etch adhesives on Enterococcus faecalis on days 1, 7 and 14 with the use of modified direct contact test. Materials and methods. The modified directcontact test was used to evaluate the antibacterial effect of Adper Easy One, Bond Force, Clearfil S3 Bond, Futurabond M, G-Bond, iBond and OptiBond All-in-one adhesives on Enterococcus faecalis after aging the samples in phosphate-buffered saline for one, seven and fourteen days. Data were analyzed using one-way ANOVA and post hoc Tukey tests. Aging effect of each adhesive was evaluated by paired-sample test. In this study, P<0.05 was considered significant. Results. All the tested adhesives exhibited antibacterial activity after one day and had significant differences with the positive control group (P<0.05). After one week, OptiBond All-in-one, iBond and Futurabond M exhibited significant differences in bacterial growth from ot...

Photomedicine and Laser Surgery, 2014

As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms ... more As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms will become more resistant to commonly used antibacterial irrigants. Photodynamic therapy (PDT) has been used to kill resistant bacteria organized in a biofilm. This study aimed to investigate the antimicrobial effectiveness of 1% sodium hypochlorite (NaOCl), 2.5% NaOCl, and PDT on E. faecalis biofilm at different stages of development. In this study 4-, 6-, and 8-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS), PDT, or 1% and 2.5% NaOCl. Dentin chip suspensions were used for colony forming units (CFU) counting to estimate remaining E. faecalis counts. PDT and 2.5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 81.88%, 85.73%, and 78.62% reductions of bacterial counts in 4-, 6-, and 8-week-old biofilms, respectively, which was significantly more than PBS. The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival and residual bacteria increase with biofilm aging. PDT and the 2.5% NaOCl solution were equally efficient in completely eliminating E. faecalis biofilms at all three stages.

Iranian Journal of Orthodontics, Jul 15, 2013