Mineral Trioxide Aggregate ( MTA) in Dentistry Its characteristics and consequences of serum contamination

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Mineral Trioxide Aggregate ( MTA) in Dentistry Its characteristics and consequences of serum contamination

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The Prevalence of EBV and KSHV in Odontogenic Lesions

Objectives: Odontogenic lesions evolve as a result of altered dental development. This study aimed to evaluate the prevalence and the coinfection of Epstein-Barr virus (EBV) and Kaposi sarcoma–associated herpesvirus (KSHV) in radicular cysts, dentigerous cysts, odontogenic keratocysts, and ameloblastomas. Methods: Polymerase chain reaction (PCR) was used to analyse 66 cases of odontogenic lesions for the presence of EBV-DNA and KSHV-DNA. These lesions were 15 radicular cysts, 16 dentigerous cysts, 18 odontogenic keratocysts, and 17 ameloblastomas. Results: EBV-DNA was detected in 24 (36.4%) of the studied samples as follows: 6 samples (40.0%) of radicular cysts, 4 (25.0%) of dentigerous cysts, 10 (55.6 %) of odontogenic keratocysts, and 4 (23.5%) of ameloblastomas (P = .168). KSHV-DNA was found in 16 (24.2%) of the studied samples as follows: 1 sample (6.7%) of radicular cysts, 6 (37.5%) of dentigerous cysts, 8 (44.4 %) of odontogenic keratocysts, and 1 (5.9%) of ameloblastomas (P = .001). Additionally, EBV and KSHV were positively correlated in all studied samples (P = .002). Conclusions: Both EBV and KSHV are found in odontogenic cysts and ameloblastomas. KSHV and EBV are more prevalent in odontogenic keratocysts than in other studied odontogenic lesions. Further, there is a high prevalence of EBV and KSHV coinfection in odontogenic cysts and ameloblastomas

Comparing the Effectiveness of Different Dentinal Desensitizing Agents: In Vitro Study

Objectives. To evaluate the in vitro effectiveness of desensitizing agents in reducing dentine permeability. Methods. The efficacy of desensitizing agents in reducing dentine permeability by occluding dentine tubules was evaluated using a fluid filtration device that conducts at 100 cmH2O (1.4 psi) pressure, and SEM/EDX analyses were evaluated and compared. Forty-two dentine discs (n=42) of 1±0.2 mm width were obtained from caries-free permanent human molars. Thirty dentine discs (n=30) were randomly divided into 3 groups (n=10): Group 1: 2.7% wt. monopotassium-monohydrogen oxalate (Mp-Mh oxalate), Group 2: RMGI XT VAR, and Group 3: LIQ SiO2. Dentine permeability was measured following treatment application after 10 minutes, storage in artificial saliva after 10 minutes and 7 days, and citric acid challenge for 3 minutes. Data were analysed with a repeated measures ANOVA test. Dentine discs (n=12) were used for SEM/EDX analyses to acquire data on morphological changes on dentine surface and its mineral content after different stages of treatment. Results. Desensitizing agents’ application on the demineralized dentine discs exhibited significant reduction of permeability compared to its maximum acid permeability values. Mp-Mh oxalate showed a significant reduction in dentine permeability (p<0.05) when compared to RMGI XT VAR and LIQ SiO2. On SEM/EDX analysis, all the agents formed mineral precipitates that occluded the dentine tubules. Conclusions. 2.7% wt. monopotassium-monohydrogen oxalate was significantly effective in reducing dentine permeability compared to RMGI XT VAR and LIQ SiO2

Comparative Evaluation of Accuracy of Different Apex Locators: Propex IQ, Raypex 6, Root ZX, and Apex ID with CBCT and Periapical Radiograph—In Vitro Study

Objectives. This study aimed to validate the accuracy of working length (WL) measurements obtained with the newly introduced Propex IQ apex locator and to compare it with the latest generations of other electronic apex locators, CBCT, and conventional periapical radiographs by using the actual WL measurements obtained by using an endodontics microscope as a reference. Materials and Methods. Thirty-five extracted single-rooted human mandibular first premolars with curvatures from 10° to 20° were selected according to the inclusion and exclusion criteria and cut at the cementoenamel junction to achieve a standard reference point for WL determination. The actual WL was obtained by inserting a size-15 k-file in the root canal until the tip of the file was visible under an endodontic microscope. The definitive WL was measured using Propex IQ (Dentsply Sirona), Raypex 6 (VDW Dental), Root ZX (Morita), and Apex ID (Kerr Dental). In addition, radiographic WL was obtained using periapical radiographs and CBCT. One-way ANOVA was used for comparisons of the WL values, with a p value < 0.05. The percentage of success of each method for determination of the definitive WL was assessed using cross-tabulation and chi-square tests. Results. CBCT radiographs and Propex IQ apex locator yielded the most accurate WL measurements in comparison with the actual WL measurements (p<0.05). Raypex 6, Root ZX, and Apex ID yielded more accurate WL measurements than conventional periapical radiographs (p<0.05). Periapical radiographs yielded the least accurate WL measurements in comparison with the actual WL values (p<0.05). Conclusions. Within the limitations of this study, the Propex IQ apex locator showed higher accuracy than Raypex 6, Root ZX, and Apex ID for WL determination in the root canal. Nevertheless, CBCT radiographs yielded the maximum accuracy for WL measurements