Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientatio... more Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed. Methods and materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukey's test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual wall was thinner in the middle third of the mesial root compared to the distal root (P<0.05). Conclusion: The lingual wall was the thinnest in C-shaped root canals of mandibular second molars of an Iranian population. Type, number and pathway of canals may vary from the orifice to the apex.
Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientatio... more Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed. Methods and Materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukey’s test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual...
Bioscience Biotechnology Research Communications, 2017
The fi rst and main goal of root canal treatment is the elimination of microorganisms from the co... more The fi rst and main goal of root canal treatment is the elimination of microorganisms from the contaminated root canal system and providing an environment for the healing of periapical tissues. Instrumentation alone cannoteffectivelyclean the complex root canal system. Souse of irrigantsalong mechanicalpreparationis required. But no single solution is able to fulfi ll these actions completely. Chlorhexidineis one of the substances thatis usedas anirrigantin endodontics. It has broadantimicrobialspectrum, but itdoes not have theability todissolveorganictissues. It has been shownthat theaddition ofsurfactantin thesolution can increasesthe abilityof dissolvetissue.In this in vitro study tissue-dissolving capacity of sodium hypochlorite (5/25% and 2/5%), chlorhexidine (0/2%) and modifi ed chlorhexidine (chlorhexidine + benzalkonium chloride and chlorhexidine + sodium lauryl solphate) were compared.Tissue samples prepared from bovine pulp and each of the samples immersed for 20 minutes in each test solution (changing the solution every 2 minutes).The sampleswereweighedbefore and aftertesting. The weight difference divided by the initial weight of the tissue sample, multiplied by 100, was defi ned as the percentage of tissue solubility.NaOCl 5/25% was more solublethantheothersolutions. ExceptCHX 0/2% and salineno statistically signifi cant differences was found between the tissuedissolving properties of othersolutions and NaOCl 5/25%.The results of this study indicate that the use of 0/2%CHX+2%SLS as irrigant in endodontic can show similar effect with NaOCl 5/25% in the solubility.
Background and aims. Biocompatibility of root-end filling materials is a matter of debate. The ai... more Background and aims. Biocompatibility of root-end filling materials is a matter of debate. The aim of this study was to compare the biocompatibility of a variety of commercial ProRoot WMTA cements and a resin-based cement (Geristore®) with different pH values of setting reaction and different aluminum contents, implanted into the subcutaneous connective tissue of rats at various time intervals. Materials and methods. Fifty Sprague-Dawley rats were used in this study. Polyethylene tubes were filled with Angelus WMTA, ProRoot WMTA, Bioaggregate, and Geristore. Empty control tubes were implanted into subcutaneous tissues and harvested at 7-, 14-, 28-and 60-day intervals. Tissue sections of 5 μm were stained with hematoxylin and eosin and observed under a light microscope. Inflammatory reactions were categorized as 0, none (without inflammatory cells); 1, mild (inflammatory cells ≤25); 2, moderate (25-125 inflammatory cells); and 3, severe (>125 inflammatory cells). Statistical analysis was performed with Kruskal-Wallis and Mann Whitney U tests. Results. ProRoot WMTA and Angelus elicited significantly less inflammation than other materials (P<0.05). After 7 days, however, all the materials induced significantly more inflammation than the controls (P<0.05). Angelus-MTA group exhibited no significant differences from the Bioaggregate group (P=0.15); however, ProRoot WMTA elicited significantly less inflammation than Bioaggregate (P=0.02). Geristore induced significantly more inflammation than other groups (P<0.05). Conclusion. Geristore induced an inflammatory response higher than ProRoot WMTA; therefore, it is not recommended for clinical use.
Background: Otomycosis is a superficial mycotic infection of the outer ear canal caused by many s... more Background: Otomycosis is a superficial mycotic infection of the outer ear canal caused by many saprophytic fungi that could be considered as causative agents. Detection of the fungal agents in the external auditory canal could be valuable to determine the potential risk of otomycosis. The aim of this study was to identify the mycoflora of the human auditory canal in healthy individuals in Shiraz, southern Iran. Methods: During three months, a total of 486 ear samples of 243 healthy individuals (100 females and 143 males) were randomly collected by sterile swabs and cultivated on Mycosel and Sabouraud dextrose agar supplemented with antibiotics. Fungal isolates were identified using conventional methods and chromogenic media. Results: Ten point twenty eight percent of the individuals were positive for ear fungal infections. Fungal species belonged to eight genera including Penicillium, Cladosporium, Candida, Aspergillus, Alternaria, Rodotorula, Exophiala and Dematiaceous fungi. In this study, Aspergillus niger, the major cause of otomycosis, was not isolated. Conclusion: Our findings suggest that the normal fungal otic infections in the presence of predisposing factors could be a potential cause for otomycosis.
Objective: Many patients suffering from viral infections attend to health care centers. Data gath... more Objective: Many patients suffering from viral infections attend to health care centers. Data gathered from viral infections is limited to specific cases such as AIDS, viral hepatitis and Influenza. There is a significant lack of reliable documentation about other viral infections. In this study the prevalence and related costs of viral infections in hospitals of Shiraz University of Medical Sciences were reviewed. Methodology: In this cross-sectional study the data were extracted from files of 1319 patients with viral infection admitted in two university hospitals during a five year period (1999-2004). The frequencies of different viral infections along with their demographic data were analyzed. Results: The mean age of the patients was 29.24 with the range of 90 years. Hospitalization days were 8636 in 40 different wards in two hospitals. US$ 30.84 was the daily mean cost for each admitted patient. Viral meningitis was most frequent (14.2%) and 8.4% of patients died during hospitalization. Conclusion: This study confirms the necessity of expanding management programs for viral infections especially hepatitis B in youths in Iran. Unspecified viral infections cost much more than specified viral diseases. Viral infection costs can be reduced by finding more sensitive and specific diagnostic methods.
The root fracture resistance (RFR) of premolars extracted from diabetic patients and the effect o... more The root fracture resistance (RFR) of premolars extracted from diabetic patients and the effect of biomaterials: white mineral trioxide aggregate (WMTA) and WMTA+Na2HPO4 as an additive, on enhancing RFR were evaluated. Diabetic and non‐diabetic teeth were divided into 4 subgroups (n = 5): root canals were obturated with WMTA, WMTA+Na2HPO4, gutta‐percha and one unfilled (control). A plunger (1 mm diameter) applied a downward compressive load with crosshead speed of 1 mm min−1 on the specimens mounted on resin blocks, and the ultimate force to fracture was measured. The mean RFR values of diabetic specimens were significantly lower. The lowest and highest means of RFR were recorded in the control and WMTA, in normal group and the control and WMTA+Na2HPO4 in the diabetic group, respectively. The RFR in diabetic patients was significantly lower, indicating their higher susceptibility to fracture under vertical forces. The use of WMTA (with or without Na2HPO4) for obturation enhances the...
INTRODUCTION Endodontic sealers play a vital role in the obturation of root canal space. The aim ... more INTRODUCTION Endodontic sealers play a vital role in the obturation of root canal space. The aim of this study was to evaluate the utility of a recently developed Polyurethane Expandable Sealer (PES), along with its cytotoxicity and dimensional changes. METHODS L929 fibroblasts and an MTS assay were used to determine the cytotoxicity of dental sealers (AH Plus, Sure-Seal Root™, and the PES) at 24, 48, 72, and 96 hours. An advanced choroidal neovascularization (CNV) model was used to assess the effect of these sealers on angiogenesis. Thirty-six extracted single-rooted human teeth were prepared and randomly divided into three groups (n=12). Obturation was performed with gutta-percha and a sealer using lateral compaction: group 1 - AH Plus, group 2 - Sure-Seal, and group 3 - PES. The average depth of sealer penetration into dentinal tubules was measured with an SEM. Data were analyzed using one-way ANOVA and Post-hoc Tukey tests (level of significance, P <0.05). RESULTS The values of MTS, CNV, and penetration depth of PES were significantly higher than in other experimental groups (P <0.05). The lowest values were seen in specimens of AH Plus, while the highest were detected in PES groups. CONCLUSIONS PES showed promising results in terms of biocompatibility and dentinal tubules adaptation and penetration.
INTRODUCTION This study investigated the fatigue and fracture modes of RaCe and ProTaper rotary i... more INTRODUCTION This study investigated the fatigue and fracture modes of RaCe and ProTaper rotary instruments. MATERIALS AND METHODS Fatigue resistance was evaluated by rotating the files 30° or 60° and with 2 or 5mm radius of curvature. RaCe taper 06 size 25 and ProTaper F1 files (n=40) were used. The number of rotations to failure was analyzed by two-way ANOVA and independent sample t-test. Fracture surfaces were examined under a scanning electron microscope. RESULTS Both files exhibited significantly more resistance to fracture when angle severity was reduced and increase in curvature radius (P=0.000). ProTaper demonstrated higher number of cycle of failure (P=0.0029) in one group (r=5mm, 60º). SEM observation revealed fatigue mark/features in 17 specimens, shear characteristics in 37 samples, and tensile overload in 26 samples. CONCLUSION Radius of curvature was the main factor in torsional and fatigue failures.
INTRODUCTION Adequate root canal seal following retreatment is essential for a successful outcome... more INTRODUCTION Adequate root canal seal following retreatment is essential for a successful outcome. Resilon/Epiphany (R/E) obturation system has been introduced as a substitute for conventional gutta-percha/sealer method. This in vitro study compared the amount of apical microleakage of R/E with gutta-percha/AH26 (GP/AH26) sealer as secondary root canal filling following retreatment in human teeth. MATERIALS AND METHODS Fifty human single-rooted lower premolar teeth were selected. After preparing them with ProTaper rotary NiTi instruments, all the canals were obturated using GP/AH26 sealer. After 10 days, all the samples were retreated using the same rotary NiTi instruments. The samples were divided randomly into two experimental groups A and B (n=20) and positive and negative control groups (n=5). In group A, all canals were obturated using GP/AH26 sealer and in group B all canals were obturated using R/E. After one week incubation in 37˚C with 100% humidity, the amount of apical mi...
OBJECTIVES This study aimed to determine the success rate of retromolar canal (RMC) infiltration ... more OBJECTIVES This study aimed to determine the success rate of retromolar canal (RMC) infiltration following the failure of inferior alveolar nerve block (IANB) injections for the anesthesia of mandibular first molars with acute irreversible pulpitis. MATERIALS AND METHODS An IANB injection was administered for 50 patients with acute irreversible pulpitis. Lip numbness was set as the sign of anesthesia and further evaluated and confirmed with pulp sensibility tests after 10-15 min. Access cavity preparation was commenced unless the patient felt any pain; in this case, an RMC infiltration injection was given. The success rate was determined through the patients' recording of the presence, absence, or reduction of pain severity during access cavity preparation using the Heft-Parker visual analog scale. RESULTS Seven patients (14%) did not experience any pain by pulp sensibility tests and during access cavity preparation after IANB injection. Twenty-five (58.1%) of the remaining 43 patients who had the RMC infiltration injection had reduced pain, and four patients (9.3%) experienced no pain after the RMC infiltration. Fourteen patients (32.5%) experienced no change in pain. Chi-squared test results revealed that the percentage of patients with reduced pain was higher than that of other patients (P < 0.001). CONCLUSIONS RMC infiltration, along with IANB, significantly reduced the pain felt by patients and increased the success of the anesthetic technique for root canal treatment of mandibular first molars with acute irreversible pulpitis. CLINICAL RELEVANCE The administration of RMC infiltration can enhance the success of the IANB technique for anesthetizing mandibular first molars exhibiting acute irreversible pulpitis.
Surface alterations of instruments were investigated after single and multiple uses in the root c... more Surface alterations of instruments were investigated after single and multiple uses in the root canals. XP‐endo Shaper (n = 5) and WaveOne GOLD (n = 5) files were used until the separation of the instruments occurred. The apical 3‐mm and separated fragments were analysed by SEM to determine the changes in the instruments and the cross‐sections of the separated fragments. Each group was divided into five subgroups: control, first, second, third and fourth molar. The results were reported descriptively for each group. In the XP‐endo Shaper group, microcracks started to appear after the second use, and pitting and galvanic corrosion occurred after the third use. During the fourth use, microcracks propagated, resulting in ductile fracture while it happened after the third use in the second group. The single use of XP‐endo Shaper and WaveOne GOLD was safe without any major changes on their surfaces. Reciprocating motion was not necessarily superior to full rotation motion.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Gutta-percha must be removed from the root canal space during retreatment to ensure a more favora... more Gutta-percha must be removed from the root canal space during retreatment to ensure a more favorable outcome. The aim of this study was to compare the efficacy of hand instruments, RaCe and RaCe plus XP-endo finisher instruments in removal of gutta-percha from root canal walls during retreatment. Thirty single-rooted premolars were prepared, obturated, and divided into three groups according to retreatment method; in group 1, retreatment was carried out by hand instruments, while in groups 2 and 3 retreatment was done using RaCe rotary files alone or accompanied by XP-endo finisher instruments, respectively. After retreatment, teeth were sectioned longitudinally and photographic images were taken. The amount of remaining gutta-percha in coronal, middle and apical thirds was quantified using Image J software. The two-way ANOVA and post hoc Tukey's tests were used to analyze data. The level of significance was set at 0.05. RaCe cleaned the apical third significantly better than ha...
Photodiagnosis and photodynamic therapy, Jan 26, 2016
The treatment of periodontal disease focuses on eradication or suppression of the pathogenic micr... more The treatment of periodontal disease focuses on eradication or suppression of the pathogenic microbiota within the periodontal pocket. There are some mechanical and chemical ways, and recently antimicrobial photodynamic therapy to eliminate the bacteria. The aim of this in vitro study was to compare the effects of 2% chlorhexidine gel, 2% metronidazole in Orabase, antimicrobial photodynamic therapy with Emundo solution and Emundo solution on P. gingivalis. The antibacterial activities of 2% CHX gel, 2% Metronidazole in Orabase, Emundo+Laser (an infra-red laser diode of 810nm, 300mW, continuous mode radiation, 30s and energy density of 11.5J/cm2), and Emundo against P. gingivalis were tested in vitro using two different methods; (1) Counting CFU/mL and (2) agar diffusion test (ADT). Data of CFU/mL were analyzed using one way ANOVA and Post hoc Tukey test (p<0.05). Data obtained from ADT test were analyzed using Kruskal-Wallis. The percentage of colony-forming units reduction was (...
Quintessence international (Berlin, Germany : 1985), 2012
To compare the efficacy of ProFile File cleaner and a nanostructured foam in removing debris from... more To compare the efficacy of ProFile File cleaner and a nanostructured foam in removing debris from two rotary nickel-titanium instruments during and after instrumentation. Twenty mandibular premolars were decoronated and instrumented up to either no. 40.04 RaCe (no. 40.04) or K3 (no. 40.04) instruments (n = 10). Each group of files was randomly divided into two groups: ProFile File cleaner and Nano Foam cleaner. The instruments were examined under a scanning electron microscope (SEM) before and after placement into the canals. Subsequently, instruments were introduced into each cleaner and examined again under SEM. The amount of debris removal from the instruments was determined by ImageJ software. Data were subjected to Kruskal-Wallis and Mann-Whitney tests at a .05 level of significance. The amount of debris removal was significantly different between the groups (P = .002). The amount of debris removed was significantly higher in K3 with Nano Foam cleaner than ProFile File cleaner ...
Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientatio... more Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed. Methods and materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukey's test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual wall was thinner in the middle third of the mesial root compared to the distal root (P<0.05). Conclusion: The lingual wall was the thinnest in C-shaped root canals of mandibular second molars of an Iranian population. Type, number and pathway of canals may vary from the orifice to the apex.
Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientatio... more Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed. Methods and Materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukey’s test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual...
Bioscience Biotechnology Research Communications, 2017
The fi rst and main goal of root canal treatment is the elimination of microorganisms from the co... more The fi rst and main goal of root canal treatment is the elimination of microorganisms from the contaminated root canal system and providing an environment for the healing of periapical tissues. Instrumentation alone cannoteffectivelyclean the complex root canal system. Souse of irrigantsalong mechanicalpreparationis required. But no single solution is able to fulfi ll these actions completely. Chlorhexidineis one of the substances thatis usedas anirrigantin endodontics. It has broadantimicrobialspectrum, but itdoes not have theability todissolveorganictissues. It has been shownthat theaddition ofsurfactantin thesolution can increasesthe abilityof dissolvetissue.In this in vitro study tissue-dissolving capacity of sodium hypochlorite (5/25% and 2/5%), chlorhexidine (0/2%) and modifi ed chlorhexidine (chlorhexidine + benzalkonium chloride and chlorhexidine + sodium lauryl solphate) were compared.Tissue samples prepared from bovine pulp and each of the samples immersed for 20 minutes in each test solution (changing the solution every 2 minutes).The sampleswereweighedbefore and aftertesting. The weight difference divided by the initial weight of the tissue sample, multiplied by 100, was defi ned as the percentage of tissue solubility.NaOCl 5/25% was more solublethantheothersolutions. ExceptCHX 0/2% and salineno statistically signifi cant differences was found between the tissuedissolving properties of othersolutions and NaOCl 5/25%.The results of this study indicate that the use of 0/2%CHX+2%SLS as irrigant in endodontic can show similar effect with NaOCl 5/25% in the solubility.
Background and aims. Biocompatibility of root-end filling materials is a matter of debate. The ai... more Background and aims. Biocompatibility of root-end filling materials is a matter of debate. The aim of this study was to compare the biocompatibility of a variety of commercial ProRoot WMTA cements and a resin-based cement (Geristore®) with different pH values of setting reaction and different aluminum contents, implanted into the subcutaneous connective tissue of rats at various time intervals. Materials and methods. Fifty Sprague-Dawley rats were used in this study. Polyethylene tubes were filled with Angelus WMTA, ProRoot WMTA, Bioaggregate, and Geristore. Empty control tubes were implanted into subcutaneous tissues and harvested at 7-, 14-, 28-and 60-day intervals. Tissue sections of 5 μm were stained with hematoxylin and eosin and observed under a light microscope. Inflammatory reactions were categorized as 0, none (without inflammatory cells); 1, mild (inflammatory cells ≤25); 2, moderate (25-125 inflammatory cells); and 3, severe (>125 inflammatory cells). Statistical analysis was performed with Kruskal-Wallis and Mann Whitney U tests. Results. ProRoot WMTA and Angelus elicited significantly less inflammation than other materials (P<0.05). After 7 days, however, all the materials induced significantly more inflammation than the controls (P<0.05). Angelus-MTA group exhibited no significant differences from the Bioaggregate group (P=0.15); however, ProRoot WMTA elicited significantly less inflammation than Bioaggregate (P=0.02). Geristore induced significantly more inflammation than other groups (P<0.05). Conclusion. Geristore induced an inflammatory response higher than ProRoot WMTA; therefore, it is not recommended for clinical use.
Background: Otomycosis is a superficial mycotic infection of the outer ear canal caused by many s... more Background: Otomycosis is a superficial mycotic infection of the outer ear canal caused by many saprophytic fungi that could be considered as causative agents. Detection of the fungal agents in the external auditory canal could be valuable to determine the potential risk of otomycosis. The aim of this study was to identify the mycoflora of the human auditory canal in healthy individuals in Shiraz, southern Iran. Methods: During three months, a total of 486 ear samples of 243 healthy individuals (100 females and 143 males) were randomly collected by sterile swabs and cultivated on Mycosel and Sabouraud dextrose agar supplemented with antibiotics. Fungal isolates were identified using conventional methods and chromogenic media. Results: Ten point twenty eight percent of the individuals were positive for ear fungal infections. Fungal species belonged to eight genera including Penicillium, Cladosporium, Candida, Aspergillus, Alternaria, Rodotorula, Exophiala and Dematiaceous fungi. In this study, Aspergillus niger, the major cause of otomycosis, was not isolated. Conclusion: Our findings suggest that the normal fungal otic infections in the presence of predisposing factors could be a potential cause for otomycosis.
Objective: Many patients suffering from viral infections attend to health care centers. Data gath... more Objective: Many patients suffering from viral infections attend to health care centers. Data gathered from viral infections is limited to specific cases such as AIDS, viral hepatitis and Influenza. There is a significant lack of reliable documentation about other viral infections. In this study the prevalence and related costs of viral infections in hospitals of Shiraz University of Medical Sciences were reviewed. Methodology: In this cross-sectional study the data were extracted from files of 1319 patients with viral infection admitted in two university hospitals during a five year period (1999-2004). The frequencies of different viral infections along with their demographic data were analyzed. Results: The mean age of the patients was 29.24 with the range of 90 years. Hospitalization days were 8636 in 40 different wards in two hospitals. US$ 30.84 was the daily mean cost for each admitted patient. Viral meningitis was most frequent (14.2%) and 8.4% of patients died during hospitalization. Conclusion: This study confirms the necessity of expanding management programs for viral infections especially hepatitis B in youths in Iran. Unspecified viral infections cost much more than specified viral diseases. Viral infection costs can be reduced by finding more sensitive and specific diagnostic methods.
The root fracture resistance (RFR) of premolars extracted from diabetic patients and the effect o... more The root fracture resistance (RFR) of premolars extracted from diabetic patients and the effect of biomaterials: white mineral trioxide aggregate (WMTA) and WMTA+Na2HPO4 as an additive, on enhancing RFR were evaluated. Diabetic and non‐diabetic teeth were divided into 4 subgroups (n = 5): root canals were obturated with WMTA, WMTA+Na2HPO4, gutta‐percha and one unfilled (control). A plunger (1 mm diameter) applied a downward compressive load with crosshead speed of 1 mm min−1 on the specimens mounted on resin blocks, and the ultimate force to fracture was measured. The mean RFR values of diabetic specimens were significantly lower. The lowest and highest means of RFR were recorded in the control and WMTA, in normal group and the control and WMTA+Na2HPO4 in the diabetic group, respectively. The RFR in diabetic patients was significantly lower, indicating their higher susceptibility to fracture under vertical forces. The use of WMTA (with or without Na2HPO4) for obturation enhances the...
INTRODUCTION Endodontic sealers play a vital role in the obturation of root canal space. The aim ... more INTRODUCTION Endodontic sealers play a vital role in the obturation of root canal space. The aim of this study was to evaluate the utility of a recently developed Polyurethane Expandable Sealer (PES), along with its cytotoxicity and dimensional changes. METHODS L929 fibroblasts and an MTS assay were used to determine the cytotoxicity of dental sealers (AH Plus, Sure-Seal Root™, and the PES) at 24, 48, 72, and 96 hours. An advanced choroidal neovascularization (CNV) model was used to assess the effect of these sealers on angiogenesis. Thirty-six extracted single-rooted human teeth were prepared and randomly divided into three groups (n=12). Obturation was performed with gutta-percha and a sealer using lateral compaction: group 1 - AH Plus, group 2 - Sure-Seal, and group 3 - PES. The average depth of sealer penetration into dentinal tubules was measured with an SEM. Data were analyzed using one-way ANOVA and Post-hoc Tukey tests (level of significance, P <0.05). RESULTS The values of MTS, CNV, and penetration depth of PES were significantly higher than in other experimental groups (P <0.05). The lowest values were seen in specimens of AH Plus, while the highest were detected in PES groups. CONCLUSIONS PES showed promising results in terms of biocompatibility and dentinal tubules adaptation and penetration.
INTRODUCTION This study investigated the fatigue and fracture modes of RaCe and ProTaper rotary i... more INTRODUCTION This study investigated the fatigue and fracture modes of RaCe and ProTaper rotary instruments. MATERIALS AND METHODS Fatigue resistance was evaluated by rotating the files 30° or 60° and with 2 or 5mm radius of curvature. RaCe taper 06 size 25 and ProTaper F1 files (n=40) were used. The number of rotations to failure was analyzed by two-way ANOVA and independent sample t-test. Fracture surfaces were examined under a scanning electron microscope. RESULTS Both files exhibited significantly more resistance to fracture when angle severity was reduced and increase in curvature radius (P=0.000). ProTaper demonstrated higher number of cycle of failure (P=0.0029) in one group (r=5mm, 60º). SEM observation revealed fatigue mark/features in 17 specimens, shear characteristics in 37 samples, and tensile overload in 26 samples. CONCLUSION Radius of curvature was the main factor in torsional and fatigue failures.
INTRODUCTION Adequate root canal seal following retreatment is essential for a successful outcome... more INTRODUCTION Adequate root canal seal following retreatment is essential for a successful outcome. Resilon/Epiphany (R/E) obturation system has been introduced as a substitute for conventional gutta-percha/sealer method. This in vitro study compared the amount of apical microleakage of R/E with gutta-percha/AH26 (GP/AH26) sealer as secondary root canal filling following retreatment in human teeth. MATERIALS AND METHODS Fifty human single-rooted lower premolar teeth were selected. After preparing them with ProTaper rotary NiTi instruments, all the canals were obturated using GP/AH26 sealer. After 10 days, all the samples were retreated using the same rotary NiTi instruments. The samples were divided randomly into two experimental groups A and B (n=20) and positive and negative control groups (n=5). In group A, all canals were obturated using GP/AH26 sealer and in group B all canals were obturated using R/E. After one week incubation in 37˚C with 100% humidity, the amount of apical mi...
OBJECTIVES This study aimed to determine the success rate of retromolar canal (RMC) infiltration ... more OBJECTIVES This study aimed to determine the success rate of retromolar canal (RMC) infiltration following the failure of inferior alveolar nerve block (IANB) injections for the anesthesia of mandibular first molars with acute irreversible pulpitis. MATERIALS AND METHODS An IANB injection was administered for 50 patients with acute irreversible pulpitis. Lip numbness was set as the sign of anesthesia and further evaluated and confirmed with pulp sensibility tests after 10-15 min. Access cavity preparation was commenced unless the patient felt any pain; in this case, an RMC infiltration injection was given. The success rate was determined through the patients' recording of the presence, absence, or reduction of pain severity during access cavity preparation using the Heft-Parker visual analog scale. RESULTS Seven patients (14%) did not experience any pain by pulp sensibility tests and during access cavity preparation after IANB injection. Twenty-five (58.1%) of the remaining 43 patients who had the RMC infiltration injection had reduced pain, and four patients (9.3%) experienced no pain after the RMC infiltration. Fourteen patients (32.5%) experienced no change in pain. Chi-squared test results revealed that the percentage of patients with reduced pain was higher than that of other patients (P < 0.001). CONCLUSIONS RMC infiltration, along with IANB, significantly reduced the pain felt by patients and increased the success of the anesthetic technique for root canal treatment of mandibular first molars with acute irreversible pulpitis. CLINICAL RELEVANCE The administration of RMC infiltration can enhance the success of the IANB technique for anesthetizing mandibular first molars exhibiting acute irreversible pulpitis.
Surface alterations of instruments were investigated after single and multiple uses in the root c... more Surface alterations of instruments were investigated after single and multiple uses in the root canals. XP‐endo Shaper (n = 5) and WaveOne GOLD (n = 5) files were used until the separation of the instruments occurred. The apical 3‐mm and separated fragments were analysed by SEM to determine the changes in the instruments and the cross‐sections of the separated fragments. Each group was divided into five subgroups: control, first, second, third and fourth molar. The results were reported descriptively for each group. In the XP‐endo Shaper group, microcracks started to appear after the second use, and pitting and galvanic corrosion occurred after the third use. During the fourth use, microcracks propagated, resulting in ductile fracture while it happened after the third use in the second group. The single use of XP‐endo Shaper and WaveOne GOLD was safe without any major changes on their surfaces. Reciprocating motion was not necessarily superior to full rotation motion.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Gutta-percha must be removed from the root canal space during retreatment to ensure a more favora... more Gutta-percha must be removed from the root canal space during retreatment to ensure a more favorable outcome. The aim of this study was to compare the efficacy of hand instruments, RaCe and RaCe plus XP-endo finisher instruments in removal of gutta-percha from root canal walls during retreatment. Thirty single-rooted premolars were prepared, obturated, and divided into three groups according to retreatment method; in group 1, retreatment was carried out by hand instruments, while in groups 2 and 3 retreatment was done using RaCe rotary files alone or accompanied by XP-endo finisher instruments, respectively. After retreatment, teeth were sectioned longitudinally and photographic images were taken. The amount of remaining gutta-percha in coronal, middle and apical thirds was quantified using Image J software. The two-way ANOVA and post hoc Tukey's tests were used to analyze data. The level of significance was set at 0.05. RaCe cleaned the apical third significantly better than ha...
Photodiagnosis and photodynamic therapy, Jan 26, 2016
The treatment of periodontal disease focuses on eradication or suppression of the pathogenic micr... more The treatment of periodontal disease focuses on eradication or suppression of the pathogenic microbiota within the periodontal pocket. There are some mechanical and chemical ways, and recently antimicrobial photodynamic therapy to eliminate the bacteria. The aim of this in vitro study was to compare the effects of 2% chlorhexidine gel, 2% metronidazole in Orabase, antimicrobial photodynamic therapy with Emundo solution and Emundo solution on P. gingivalis. The antibacterial activities of 2% CHX gel, 2% Metronidazole in Orabase, Emundo+Laser (an infra-red laser diode of 810nm, 300mW, continuous mode radiation, 30s and energy density of 11.5J/cm2), and Emundo against P. gingivalis were tested in vitro using two different methods; (1) Counting CFU/mL and (2) agar diffusion test (ADT). Data of CFU/mL were analyzed using one way ANOVA and Post hoc Tukey test (p<0.05). Data obtained from ADT test were analyzed using Kruskal-Wallis. The percentage of colony-forming units reduction was (...
Quintessence international (Berlin, Germany : 1985), 2012
To compare the efficacy of ProFile File cleaner and a nanostructured foam in removing debris from... more To compare the efficacy of ProFile File cleaner and a nanostructured foam in removing debris from two rotary nickel-titanium instruments during and after instrumentation. Twenty mandibular premolars were decoronated and instrumented up to either no. 40.04 RaCe (no. 40.04) or K3 (no. 40.04) instruments (n = 10). Each group of files was randomly divided into two groups: ProFile File cleaner and Nano Foam cleaner. The instruments were examined under a scanning electron microscope (SEM) before and after placement into the canals. Subsequently, instruments were introduced into each cleaner and examined again under SEM. The amount of debris removal from the instruments was determined by ImageJ software. Data were subjected to Kruskal-Wallis and Mann-Whitney tests at a .05 level of significance. The amount of debris removal was significantly different between the groups (P = .002). The amount of debris removed was significantly higher in K3 with Nano Foam cleaner than ProFile File cleaner ...
Uploads
Papers by Kasra Karamifar