Dental Research Journal最新文献

Background: Ameloblastoma is a benign odontogenic neoplasm with a high recurrence rate. Identifying cellular and molecular changes in this neoplasm may help predict the recurrence risk. Bcl-2 and galectin-3 are anti-apoptotic proteins associated with the prognosis of many neoplasms. However, there are a few studies focusing on the association between these two markers and recurrence of ameloblastoma. This study aimed to investigate the association of Bcl-2 plus galectin-3 expression and recurrence of ameloblastoma.

Materials and methods: This retrospective cross-sectional study was designed on 48 paraffin-embedded blocks diagnosed as ameloblastoma from 1998 to 2019. We retrieved follow-up data from patients' records and used immunohistochemical staining for Bcl-2 and galectin-3 antibodies. Then, we analyzed their association with recurrence using Chi-square and Mann-Whitney test as well as recurrence-free survival using Kaplan-Meier curves and linear Cox regression. The level of statistical significance was P < 0.05.

Results: Twenty-six patients had experienced the recurrence. The mean follow-up time was 93.53 months. There was a significant association between Bcl-2 plus cytoplasmic galectin-3 staining and recurrence (both P < 0.001). Furthermore, in univariate analysis, high expression of Bcl-2 was associated with less recurrence-free survival (log-rank: P = 0.020-univariable Cox: P = 0.033), but in multiple Cox regression, there was no significant association (P = 0.471). High cytoplasmic galectin-3 expression was also associated with less recurrence-free survival (log-rank: P = 0.007-univariable Cox: P = 0.015-multiple Cox: P = 0.044). Furthermore, we found a correlation between Bcl-2 and cytoplasmic galectin-3 staining (P = 0.001).

Conclusion: It seems that Bcl-2 and cytoplasmic galectin-3 staining might predict the risk of ameloblastoma recurrence. However, only the cytoplasmic galectin-3 staining might be an independent predictor of ameloblastoma recurrence, and we recommend further studies.

Background: Head-and-neck radiotherapy can change oral Candida species and lead to the development of refractory oral candidiasis resistant to the commonly prescribed antifungal medications such as fluconazole. Atorvastatin exerts an antifungal effect by inhibiting the synthesis of fungal wall ergosterol and impairing mitochondrial function. This study aimed to compare the antifungal effects of fluconazole and atorvastatin on Candida species isolated from patients undergoing head-and-neck radiotherapy.

Materials and methods: In this clinical in vitro study, swab samples were collected from 33 patients admitted to Isfahan Seyed-O-Shohada Hospital before the onset and 2 weeks after the initiation of radiotherapy. The antifungal effects of fluconazole and atorvastatin were evaluated by the microdilution test according to the Clinical and Laboratory Standards Institute standards, and measuring their minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). Data were analyzed by the Mann-Whitney U-test and the statistical significance level was considered P < 0.05.

Results: The results showed that the MIC24, MIC48, and MFC of fluconazole were significantly lower than those of atorvastatin for Candida albicans, Candida tropicalis, and Candida glabrata both before (P < 0.001 for all) and during (P < 0.001 to P = 0.003) radiotherapy.

Conclusion: According to the results, fluconazole has antifungal effects comparable to those of atorvastatin, but in much lower doses. Atorvastatin showed optimal antifungal effects but in doses beyond the clinically applicable threshold.

Background: There is ample evidence showing the development of nystatin-resistant strains in patients undergoing malignancy treatment. Amphotericin B is a polyene antifungal drug that combines with ergosterol to cause cell death and is more effective on fungal species than routine antifungals such as nystatin. This study aimed to compare the effect of nystatin and amphotericin B on fungal species isolated from patients before and during head-and-neck radiotherapy.

Materials and methods: This in vitro experimental study was performed on samples isolated from patients undergoing head-and-neck radiotherapy before and during radiotherapy at Sayed al-Shohada Hospital in Isfahan, Iran. The isolates were identified by polymerase chain reaction-restriction fragment length polymorphism. Antifungal effects were determined by the microdilution method based on clinical and laboratory standards institute standards and minimum inhibitory concentration (MIC), minimum lethal concentration (MFC), drug sensitivity, and resistance were measured. The data were analyzed by SPSS version 22 (level of significance: 0.05).

Results: Before radiotherapy, all albicans strains were sensitive to nystatin, whereas 71.4% were sensitive to amphotericin B. After radiotherapy, Candida albicans strains were 100% sensitive to nystatin and 75% sensitive to amphotericin B.

Conclusion: The present study showed that before radiotherapy, all species isolated from patients, including C. albicans, C. tropicalis, and C. glabrata, were sensitive to nystatin, whereas a percentage of albicans species showed resistance to amphotericin B. In the 2^nd week of radiotherapy, the same as before radiotherapy, all species isolated from patients were sensitive to nystatin, whereas a percentage of albicans species showed resistance to amphotericin B. In general, the current study showed that before and after radiotherapy, the antifungal effect of nystatin is greater than amphotericin B.

Background: Chronic apical periodontitis (AP) may influence the outcome of root canal treatment. Thus, it is important to diagnose AP using the best method available. This research was done to compare the diagnostic accuracy of parallel periapical radiography (PR) and different field of views (FOVs) of cone-beam computed tomography (CBCT).

Materials and methods: This ex vivo study was done on six human mandibles. After extraction of the teeth, periapical lesions with different sizes were prepared randomly by drilling a hole at the base of the socket using a bur. From among 67 sockets, 21 sockets had no lesion (control); then, all mandibles were scanned by CBCT with different FOVs and paralleling periapical technique radiography. The images were assessed by two examiners. The quantitative data were analyzed by intraclass correlation coefficient (ICC) and the qualitative data were analyzed by McNemar's test (α = 0.05). Sensitivity, specificity, and accuracy were calculated. Inter-observer agreement was assessed using kappa statistics for qualitative data and ICC for quantitative data.

Results: The quantitative scores were compared with the gold standard using ICC, which showed maximum agreement for the dental FOV of CBCT (93.3) and minimum agreement for PR (62.5) (P < 0.001). For qualitative data, maximum agreement was found for the dental FOV of CBCT (97.1%), and minimum agreement was reported for PR (59.7%). Kappa values were variable between 0.271 and 0.924 (P < 0.001). Maximum sensitivity was found for the dental FOV of CBCT (96%) and minimum sensitivity was observed for PR (51%). The inter-observer agreement was 0.922 for qualitative data and 0.90 for quantitative data (P < 0.001). There were no significant differences between CBCT with different FOVs and defect sizes (gold standard) while we found significant differences for periapical by defect sizes.

Conclusion: CBCT with dental FOV presents the highest sensitivity and diagnostic accuracy for detection and characterization of simulated AP.

Background: This study compared the antibacterial effects of 940 nm diode laser and sodium hypochlorite and chlorhexidine irrigations on Enterococcus faecalis in human permanent single-rooted teeth.

Materials and methods: In this in vitro study, 65 extracted human single-rooted teeth were prepared using the crown-down method using rotary files. The root canals were irrigated with 5.25% sodium hypochlorite, 17% ethylenediaminetetraacetic acid, and normal saline solution. After placing the roots in microtubules, they were transferred into an autoclave. The teeth were randomly divided into four groups (n = 15): laser, sodium hypochlorite, chlorhexidine, and saline. Three teeth were assigned to the positive control group and two to the negative control group. The root canals were sampled, and the colony counts were determined 24 h later. Then, antibacterial agents were applied to the canals, and immediately after, the root canals were sampled, and the colony counts were determined 24 h later. The data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests using the SPSS software version 26. The significance level was defined at P < 0.05.

Results: The results showed that sodium hypochlorite, chlorhexidine, laser, and normal saline significantly reduced bacterial colony counts, confirming their antimicrobial effects (P < 0.001). Sodium hypochlorite and chlorhexidine showed the highest antimicrobial effects, with no significant differences between the sodium hypochlorite and chlorhexidine groups (P = 0.512); however, there were significant differences between the other groups (P < 0.001).

Conclusion: According to the results, 940 nm diode laser beams significantly reduced E. faecalis counts and could be used as a new, effective, and complementary treatment in disinfecting the root canal.

Background: Periapical extrusion of debris for root retreatment will effectively improve the posttreatment inflammation and pain. The aim of this study was to investigate the extruded debris for root retreatment using XP shaper and ProTaper files.

Materials and methods: In his experimental laboratory study, 40 extracted human maxillary molars were used in this laboratory study. After disinfection and equalization of length, the samples were treated with a passive step-back technique and dressed. The samples placed in the tubes for retreatment were divided into four groups: (1) XP shaper file and hypochlorite, (2) XP shaper file and ethylenediaminetetraacetic acid (EDTA), (3) ProTaper file and hypochlorite, and (4) ProTaper file and EDTA. Then, the teeth were taken out of the tubes, and cleaned to collect the remaining apical debris. The weight of the tube and the extruded debris was measured again. Data were analyzed using the Kruskal-Wallis test (α =0.05).

Results: The highest average of extruded debris was related to the XP shaper file with EDTA solution, and the lowest average was related to the ProTaper file with hypochlorite solution. Between the two files used with EDTA and hypochlorite solution, the average debris extrusion of the XP shaper file with EDTA solution was significantly higher (P < 0.05) compared to the ProTaper and XP shaper files with hypochlorite solution (P < 0.05).

Conclusion: Regardless of the type of irrigant material, the ProTaper file can be a more suitable option than the XP shaper file for retreatment of the tooth root canal with minimal debris extrusion.

Background: This systematic review and meta-analysis aimed to assess the efficacy of autologous platelet concentrate (APCs) in comparison with coronally-advanced flap alone or in combination with connective tissue graft or other biomaterials or bioactive agents for root coverage (RC) of Miller's Class I and II gingival recession defects by measuring the keratinized mucosa width (KMW).

Materials and methods: This systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines. An electronic search of the literature was conducted in PubMed, EMBASE, Scopus, Cochrane, Web of Science, Magiran, Scientific Information Database, and Irandoc for randomized clinical trials (RCTs) that used APCs for RC in their intervention group. Eligible articles were retrieved by assessment of titles and abstracts and then the full texts. The risk of bias was assessed by the Cochrane Library Risk of Bias Assessment Tool. Meta-analysis was carried out by RevMan 5.3 software. In the case of homogeneity, variables were reported as weighted mean difference (WMD) with 95% confidence interval (CI) for each group.

Results: The search yielded 689 articles; out of which, 32 were eligible for study inclusion. Meta-analysis did not show any additional effect for RC and KMW with APCs. Clinical parameters were as follows: RC: WMD = -1.57 mm (95% CI: -2.49, -0.659; P = 0.001) and KMW: -0.106 mm (95% CI: -0.3222, 0.110; P = 0.337).

Conclusion: The application of APCs for RC of Miller's Class I and II gingival recession defects does not seem to improve the clinical parameters.

Background: The ethmoid roof separates the ethmoid cells from the anterior cranial fossa. From the medial side, the roof of the ethmoid is connected to the lateral lamella of the ethmoid plate, which is the thinnest bone at the base of the skull and is most vulnerable to damage during endoscopic surgeries. The purpose of this study is to investigate the height of the lateral lamella in patients with hypoplasia/aplasia of the paranasal sinuses and deviation of the nasal septum using reconstructed multiplanar images by cone-beam computed tomography (CBCT).

Materials and methods: In this descriptive-analytical (cross-sectional) study, 192 CBCT images (89 males and 103 females) with an age range of 18 years and older were examined. These 192 participants included 58 cases of frontal sinus (FS) hypoplasia/aplasia, 42 cases of maxillary sinus (MS) hypoplasia/aplasia, 12 cases of sphenoid sinus (SS) hypoplasia/aplasia, 40 cases of nasal septum deviation, and 40 cases as a control group. As Keros classification indicates, the depth of the olfactory fossa was estimated in three categories: type 1 (1-3 mm), type 2 (4-7 mm), and type 3 (8-16 mm). The height of the lateral lamella was measured in the coronal section in all images. The septum deviation angle was also measured in the coronal section. For statistical analysis, Shapiro-Wilk, independent t, nonparametric Mann-Whitney, Pearson correlation, and Kruskal-Wallis tests were done using the SPSS 22 software.

Results: The most common type of olfactory fossa in all disorders and the control group was type II of the Keros classification. The highest average lateral lamella height was in the SS hypoplasia group (6.226 mm) and the lowest in the FS aplasia group (4.411 mm). The lateral lamella height in FS aplasia/hypoplasia groups was significantly lower than the control group (P = 0.002 and P = 0.044). The average deviation angle of the nasal septum was 19.73° ±5.35° and no significant relationship was found between this angle and the height of lateral lamella (P = 0.938). The height of the lateral lamella in the FS hypoplasia group was significantly higher in men than in women (P = 0.019), but in other groups, there was no relationship between lateral lamella height and gender. Seventy-five percent of the participants of the nasal septum deviation group were type II of Keros classification and the remaining 25% were type I.

Conclusion: The lateral lamella height in hypoplastic/aplastic FSs is lower than normal, and this information is useful in preventing complications during endoscopic sinus surgery.

Background: With recent increases in demand for the esthetic aspects of orthodontic treatments, the use of ceramic brackets has gained more popularity. Dental demineralization is a frequent, undesired effect of microbial biofilm adhesion to orthodontic appliances. The crystalline structure of ceramics results in different material properties, and its possible effect on microbial adhesion was investigated in this study.

Materials and methods: This research was conducted experimentally and in vitro. Samples consisted of 40 monocrystalline and 40 polycrystalline brackets, further divided into two groups incubated with either Streptococcus mutans alone or S. mutans with Candida albicans. The culture medium was Tryptic Soy Broth with 20% sucrose. All samples were incubated at 37°C for 48 h. Macroscopic detachment of the formed biofilm would be the basis for adhesion scoring. The Mann-Whitney test was used to analyze the adhesion scores. In this study, a significance level of P < 0.05 was considered.

Results: The mean for adhesion score in S. mutans group was 1.85 ± 0.67 for the monocrystalline group and 2.35 ± 0.59 for the polycrystalline group (27% difference, P = 0.035). The adhesion score in S. mutans and C. albicans group was lower in the monocrystalline group (1.6 vs. 2.0) but was not statistically significant (P = 0.108).

Conclusion: This study showed that monocrystalline ceramic brackets had less overall microbial biofilm adhesion compared to polycrystalline ceramic brackets, especially when incubated with S. mutans alone. This observation might be explained primarily by lower surface roughness in monocrystalline ceramics.

Background: The aim of this study was to compare the mechanical properties of the polymer brackets with metal and ceramic brackets and verify if the polymer brackets could be used clinically.

Materials and methods: A thorough search was conducted in four electronic databases, including Scopus, PubMed, Cochrane, Ovid, and Lilacs, with article selection based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis standards. A computerized search of the database was done from January 1990 to June 2024. Two independent reviewers were involved in study selection, data extraction, and synthesis. Disagreements were resolved by discussion with a third reviewer. The risk of bias was assessed by the quality assessment tool for in vitro studies (QUIN tool). The outcomes measured included permanent deformation, hardness, and torquing capacity.

Results: Ten studies were selected after excluding duplicates, screening, and complete text reading to identify the articles that met the eligibility criteria. All ten studies showed medium risk based on the quality assessment tool for in vitro studies (QUIN Tool).

Conclusion: The following findings were obtained: Polymer brackets have lower mechanical properties in terms of torque loss, fracture resistance, hardness, and torsional creep compared to metal brackets. Among the polymers listed in the studies, it was found that polyamide exhibited low hardness and polyoxymethylene exhibited the highest torque loss. Torque deformation was highest with a ceramic-reinforced polymer bracket, followed by pure polymer. Torque deformation was minimal with metal slot- and ceramic-reinforced polymers, followed by metal slot-reinforced polymers.