International Journal of Dentistry最新文献

Background: Investigating the pattern of extension in the periapical (PA) inflammatory lesions is important in the treatment plan and prognosis of treatment. Introduction: This study evaluated the topography of PA inflammatory lesions in the first molars using cone-beam computed tomography (CBCT). Methods: In this descriptive study, 197 CBCT images about patients in the age group of 14-77 years were analyzed. The maximum extension of the PA lesion in the three orthogonal planes related to the regions of maxillary and mandibular first molars was measured and reported in millimeters. Measurements were compared based on age, gender, dental arch, and root type. Statistical analysis was performed using percentages, repeated measure ANOVA, paired t-tests, and Pearson correlation coefficient. The significant level was set at 0.05. Results: The highest total mean lesion extensions were in the vertical plane followed by the buccolingual and mesiodistal plane. There was a statistically significant difference between the extension of the PA lesion in the vertical and mesiodistal (p < 0.001), vertical and buccolingual (p =0.001), as well as the mesiodistal and buccolingual planes (p =0.027). In the maxilla and mandible, the highest mean lesion extension was in the vertical, buccolingual, and mesiodistal plane, respectively. According to the root type, there was only a statistically significant difference in lesion extension in the buccolingual plane and between the mesial and distobuccal roots (p =0.030). Conclusion: Given the limitations of the present study, regarding the extension of the PA lesion in the first molar region, the bone structure of the maxilla and mandible follows a precise and delicate pattern. In this regard, future studies in different communities and races should be designed to address this issue in different communities. In addition, CBCT is a reliable imaging method to evaluate the extension of the PA lesion both morphologically and morphometrically.

Objective: This research aimed to assess the shear bond strength (SBS) of metal brackets bonded to composite veneers using different surface preparations. Methods: One-hundred composite disks were divided into 10 different groups whereby each group combines a surface preparation (roughening or no roughening), etching agent (37% phosphoric or 9.5% hydrofluoric acid), adhesive protocol (self-etch or total-etch), and bonding agent (with or without G-Premio Bond). Orthodontic metal brackets were bonded to prepared composite surfaces by Transbond XT resin and light-cured. The prepared samples were incubated at 37˚C for 24 h and underwent thermocycling. A universal testing machine was loaded until the failure moment to assess SBS. Adhesive remnant index (ARI) was used to classify the failure sites between the composite surface and bracket base. Tukey, Fisher's exact, and chi-square tests were used for statistical analyses. Statistical significance level was 0.05. Results: Surface roughening and the type of material used for surface preparation significantly affected bond strength (p  < 0.0001). There was no significant difference in bond strength between phosphoric acid and hydrofluoric acid (p  > 0.05). The highest bond strength was observed in the group with roughening + total-etch with phosphoric acid + G-Premio Bond (10.24 ± 2.99 MPa). The lowest bond strength was found in the group without roughening, etched with phosphoric acid (1.47 ± 1.06 MPa). In the groups without roughening, ARI scores of 0 and 1 were found, while in the groups with roughening, ARI scores of 0, 1, and 4 were observed. Conclusions: The SBS with G-Premio Bond is high with ARI score 4 which may pose a risk of damage to the veneers during debonding. Therefore, surface preparation of the veneers that result in lesser bond strength should be used unless in patients with frequent bracket breakages.

Background: Molar incisor hypomineralization (MIH) presents a multifaceted challenge in pediatric dentistry, impacting diagnostics, clinical management, resource accessibility, and psychosocial care. The condition's complexity is exacerbated by diagnostic variability, overlapping clinical symptoms, and the need for tailored treatment approaches. Objectives: This study aims to explore the key challenges associated with the management of MIH in pediatric dentistry, including diagnostic precision, clinical management, resource limitations, interdisciplinary care, long-term follow-up, and psychosocial impact, and to propose strategies for overcoming these obstacles. Methods: A comprehensive literature review was conducted to identify and synthesize existing evidence on MIH's etiology, diagnosis, treatment, and prognosis. The review highlighted the barriers encountered in providing optimal care, particularly in resource-constrained settings, and explored potential solutions through clinical and interdisciplinary approaches. Results: The key findings included the need for standardized diagnostic criteria, the role of individualized treatment plans, and the importance of resource allocation. Limited access to specialized equipment and education hampers care, especially in under-resourced areas. Long-term management complexities were further compounded by the necessity for interdisciplinary collaboration and attention to psychosocial factors affecting pediatric patients. Conclusion: Effective MIH management requires standardized diagnostic protocols, resource advocacy, interdisciplinary collaboration, and holistic patient care. Advancements in research, education, and policy are essential to improve outcomes in pediatric patients. By addressing both clinical and psychosocial challenges, the overall well-being of MIH-affected children can be enhanced.

Aim: This study compared the apical transportation and centering ratio of ProTaper Next (PTN) and XP-endo Shaper (XPS) nickel titanium (NiTi) rotary files in curved root canals using cone beam computed tomography (CBCT). Methodology: The current in vitro study involved the mesiobuccal canals of mesial roots in 44 extracted mandibular first molars that exhibited apical curvature ranging from 10° to 30°. Two experimental groups were randomly formed from the teeth (n = 22) and subjected to instrumentation with PTN and XPS. CBCT scans were performed before and after instrumentation on the teeth, and the apical transport and centering ratio were calculated at 3, 4, and 5 mm from the apex. Group comparisons were conducted using an independent t-test with a significance level set at alpha = 0.05. Results: Comparisons within groups did not reveal any statistically significant differences in the magnitude of canal transportation in the buccolingual (BL) and mesiodistal (MD) directions at any level from the apex, neither in the XPS group nor in the PTN group (p > 0.05). Canal transportation in both BL and MD directions was significantly greater in PTN than in XPS (p < 0.05). The centering ratio in the MD and BL directions was the same at 3, 4, and 5 mm from the apex in the PTN (p > 0.05) and also in the XPS (p > 0.05) groups. The centering ratio was significantly higher in XPS than in PTN (p < 0.05) except at 5 mm from the apex in the MD direction and 4 and 5 mm from the apex in the BL direction (p > 0.05). Conclusions: Both buccolingually and mesiodistally, PTN led to greater apical transport than XPS and also showed a lower centering ratio.

Objective: This study aimed to assess the changes in the position and size of articular spaces and anteroposterior and mediolateral condyle dimensions following orthognathic surgery. Additionally, it evaluated the correlation between these changes and mandibular movement during surgery. Methods: This experimental study examined 31 patients (16 with Class III and 15 with Class II malocclusions) who were candidates for orthognathic surgery. Bimaxillary orthognathic surgery was performed on 23 patients, while monomaxillary orthognathic surgery (mandible) was performed on 8 patients. Condyle positioning was achieved using the classic method. In pre- and postsurgical cone beam computed tomography (CBCT) scans, the anteroposterior and mediolateral dimensions of the condyle and spaces and the intercondylar angle were measured. The results were analyzed using the Wilcoxon signed-rank test, with a p-value of less than 0.05 considered significant. Results: The medial and lateral condyle dimensions and the upper articular space did not change significantly after orthognathic surgery in both Class II and III groups. However, the posterior articular space dimensions showed a statistically significant reduction in both groups. Although the anterior articular space dimensions increased in both groups, this increase was significant only in the Class II group. Additionally, there was a significant relationship between the extent of mandibular advancement or setback and changes in both groups' anterior and posterior articular space dimensions and the upper articular space dimensions in the Class II group. Conclusion: The classic method for condyle positioning is a suitable approach for orthognathic surgery. The most notable changes were observed in the anterior and posterior articular spaces, likely due to the backward force applied to the proximal part during the fixation stage. According to the evaluations and Spearman's rho, the likelihood of changes in anterior and posterior articular space dimensions increases with more significant advancement and setback.

Objectives: This study aimed to assess the effect of cyclic loading on the amount of fixture-abutment microgap in short implants compared to standard implants. Materials and Methods: This in vitro experimental study was conducted on two groups of short and standard implants (n = 10). The microgap at the fixture-abutment interface was measured under a light microscope at ×75 magnification. The implants were mounted in an acrylic resin to simulate the jawbone. They were then subjected to cyclic loading by applying 75 N load with 1 Hz frequency along the longitudinal axis of each implant (perpendicular to the abutment surface). After 500,000 cycles, corresponding to 20 months of mastication in the oral environment, the implants were removed from the acrylic resin, and the microgap at the fixture-abutment interface was measured again under a stereomicroscope by a blinded examiner. Data were then analyzed by t-test using SPSS version 22 (α = 0.05). Results: The mean microgap was 13.59 ± 3.80 µm in the standard and 20.41 ± 11.30 µm in the short implants before cyclic loading (p=0.087). These values changed to 15.22 ± 5.44 and 24.53 ± 21.85 µm, respectively, after cyclic loading. No significant difference was noted in the amount of microgap between the standard and short implants after cyclic loading (p=0.222). Conclusion: Cyclic loading increased the amount of fixture-abutment microgap in both the standard and short implants. However, the difference in this respect was not significant between the two implant lengths. Thus, short implants could be reliably used in patients with limitations for surgery to restore function and esthetics.

Purpose: The aim of this comparative observational study is to evaluate and compare the size and position of the condyle among male and female patients with different skeletal patterns in the anterior-posterior dimension using cone beam computed tomography (CBCT) images. Materials and Methods: CBCT images of 120 patients, all prepared for other treatment purposes under the same conditions, were included in the study. The patients were classified into three groups-class I, class II, and class III-based on ANB angles and Wits analysis. The size of the condyle was measured in terms of width, height, and length. The position of the condyle was assessed by measuring the superior joint space (SS), anterior joint space (AS), and posterior joint space (PS) on the right and left sides separately. The measurements and results were analyzed using analysis of covariance (ANCOVA) and Bonferroni analysis. A statistical significance level of p  < 0.05 was considered. Results: The study found no statistically significant differences in the size of the SS and AS (p = 0.481 and p = 0.392, respectively) across different skeletal patterns. However, the size of the PS was significantly greater in class I subjects compared to class III subjects (p = 0.015). There were no statistically significant differences in condyle height and width among the different skeletal patterns (p = 0.367 and p = 0.720, respectively). In contrast, condyle length was statistically significant in class II individuals (p = 0.002) and was the lowest among the other skeletal pattern groups. Conclusions: Based on the results obtained, class I individuals have lower PS values compared to class III individuals. Additionally, class II individuals have shorter condyle lengths compared to those in class III and class I.

Objective: The successful management of necrotic pulps and apical periodontitis poses a tough challenge in endodontic therapy, as it involves addressing compromised tooth vitality and microbial invasion of root canal systems. Failure to effectively treat these conditions can lead to persistent infection and severe patient discomfort. The efficacy of double antibiotic paste (DAP), a mixture of ciprofloxacin and metronidazole, was evaluated and compared to calcium hydroxide (CH) by assessing radiographic and clinical outcomes of nonsurgical endodontic treatment in cases with necrotic pulps and the presence of apical periodontitis. Methods: Thirty maxillary anterior teeth with necrotic pulps and apical periodontitis (periapical index [PAI] = 5) were divided randomly into two experimental groups. The first group received CH dressing, while the other group filled with DAP as intracanal medicament. After 3 weeks, medicaments were removed, and teeth were obturated in both groups. Teeth were assessed clinically and radiographically at 6-month and 12-month follow-ups. A chi-square test was performed to compare the outcome between the groups. Results: None of the teeth showed complete healing in a 6-month follow-up. At the 12-month follow-up, six samples in the DAP group showed complete healing of the periapical (PA) lesion, while none of the samples in the CH group were completely healed. The PA healing outcome was as follows: in the DAP group, 40% of cases were healed, 60% healing, and 0% diseased, while in the CH group, 0% healed, 93.3% healing, and 6.7% diseased. The results of the two experimental groups in 12 months differed significantly (p  < 0.05). Conclusion: DAP group has shown significantly better outcomes compared to CH as intracanal medicament in the treatment of teeth with PA lesions. This finding suggests that DAP may offer a more effective therapeutic approach in managing necrotic pulps and apical periodontitis, potentially improving patient outcomes and treatment success rates. Trial Registration: Clinical Trial Registry identifier: IRCT2015060822615N1.

Background: XP-endo files are composed of Max-Wire alloy, which was developed by FKG Dentaire (La Chaux-de-Fonds, Switzerland). This alloy, known as Martensite-Austenite Electropolish Flex, is the first NiTi alloy used in endodontics to combine the shape memory effect with superelasticity for use in clinical practice. Objective: This article aims to provide a comprehensive overview of the existing knowledge and evidence regarding different XP-endo files and systems, XP-endo Finisher (XPEF), XP-endo Shaper (XPES), XP-endo Retreatment (XPER), XP-endo Rise (XPE-Rise), and XPE-Rise Retreatment (XPE-Rise-R), to help clinicians understand their different properties and recommended clinical uses. Moreover, this review aims to identify future research opportunities in this field. Materials and Methods: A search was performed in the PubMed database using the keywords "XP endo" or "XP-endo". A total of 309 studies were identified during the initial search, and then initial abstract screening was conducted. The inclusion criteria included any study that aimed to evaluate XP endo files and systems on permanent teeth, either in vivo or in vitro. We excluded studies that were unrelated to the subject, literature reviews, case studies, and studies that employed deciduous teeth. Finally, we performed an extensive review of the selected 130 studies, which we assessed, summarized, and classified based on the specific XP-endo file used. Conclusion: Overall, XP-endo files offer significant improvements in endodontic treatment. XPEF excels in irrigation activation and medicament removal, and XPES succeeds in canal cleaning, shaping, and retreatment. The XPER system, which incorporates the XPEF-R file, shows promise in removing root-filling materials, but its performance is inconsistent compared to other retreatment systems. We have found limited information regarding the latest XPE-Rise and XPE-Rise-R systems, additional research is required to fully determine their comparative effectiveness and optimize their clinical application.