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This experimental study investigated the effect of different intracanal irrigants on the push-out bond strength of dentin in damaged anterior primary teeth. The crowns of 90 anterior primary teeth were sectioned horizontally, 1 mm above the cementoenamel junction (CEJ). Following canal preparation with K-files, all groups except the negative control received normal saline irrigation. Canals were then irrigated with either 3% or 5.25% sodium hypochlorite (NaOCl), 2% or 0.2% chlorhexidine (CHX) solution (except negative and positive controls). The roots were filled with Metapex material and covered with a calcium hydroxide liner. In root canals, the bond was applied by self-etching and then light-cured for 20 seconds before canals were restored incrementally with composite. Stereomicroscopes were used to assess failure patterns. Push-out bond strengths (MPa ± SD) were: 3% NaOCl (16.92 ± 5.78), 5.25% NaOCl (8.96 ± 3.55), 2% CHX (14.76 ± 5.56), and 0.2% CHX (7.76 ± 2.93). Significant differences were seen across the irrigants regarding the push-out bond strength of dentin sections (P <0.001). The most frequent failures were adhesive and cohesive. NaOCl and CHX irrigants increased the push-out bond strength compared to controls. Compared to controls, both 3% NaOCl and 2% CHX irrigants significantly increased the push-out bond strength of dentin in non-vital anterior primary teeth.

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Aim: In recent years, many studies have been conducted on different materials for covering the pulp in pulpotomy. Recently, some materials such as Coldceram have been introduced that have the ability to regenerate the pulp. In this study, our aim was to compare the clinical and radiographic success of the pulpotomy of milk molars using MTA and Coldceram over 3-, 6-, and 9-month follow-ups. Methods: In this clinical trial, 42 children aged 4-9 years old who fulfilled the inclusion criteria of the study were selected. Finally, pulpotomy was conducted on 42 teeth using MTA and another 42 teeth using Coldceram in these children. Simultaneously, all teeth were permanently repaired using glass ionomer and metal veneers in the same treatment session. Then, clinical and radiographic evaluation was conducted in 3-, 6-, and 9-month follow-up periods. Results: None of the teeth showed clinical symptoms at the specified 3-, 6-, and 9-month follow-up times, and clinical success was 100% in both groups. In radiographic evaluation, the numbers of successful treatments were 42/42 (100%) and 41/42 (97%) for the teeth treated with MTA and Coldceram, respectively. Conclusion: According to this research, both materials were proven to have a 100% clinical success rate, but in the radiographic evaluation, MTA attained a higher success rate compared with Coldceram; however, this difference was not statistically significant (P = 0.36). It is recommended to consider longer follow-ups and larger sample sizes in future studies.

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Introduction: Identifying the external root resorption plays an important role in treatment planning for deciduous teeth. Although proper accuracy of digital radiography in the diagnosis of external root resorption has been established in permanent dentition, it cannot be at all generalized to the primary root being superimposed by the succeeding permanent teeth. Interestingly, no study has assessed this in primary teeth yet. Thus, this study was undertaken for the first time. Methods: This was a single-blind prospective clinical diagnostic study performed on 501 observations (observed by 3 observers) pertaining to 167 roots of 45 maxillary/mandibular primary molars (in 6-8-year-old patients) which were indicated for extraction and did have succeeding permanent teeth. Digital parallel periapical radiographs were taken before dental extraction using a PSP sensor. Radiographs were printed and examined by two pediatric dentists. After the extraction, the extent of resorption was directly measured, twice, by third and fourth observers blinded to radiographic estimates. Radiographic errors and absolute errors (mm) were calculated. Various parameters were analyzed statistically. Results: Of the roots, 56.3% were really resorbed with (mean = 5.01 ± 2.10 mm). First/second observers failed to identify 19.6% and 38.3% of roots, respectively. Average errors were -0.77 ± 2.31 and 0.14 ± 2.19 mm in girls and boys, respectively (P=0.043, t-test). The factors "side, jaw, tooth type, and root type" did not affect errors (P > 0.05). Average absolute errors were 1.79 ± 1.47 mm (significantly above zero, P < 0.0005). No evaluated factor affected it (P > 0.1). Actual lesion sizes correlated with errors (Pearson R = 0.682, P < 0.0005) but not with absolute errors (P=0.464). Conclusion: Although many deciduous roots might be missed, digital radiography might still provide rather a good accuracy in diagnosis and measurement of external root resorption up to about 1.8 mm absolute error. Observers might overestimate resorption sizes in girls and in cases with actual lesions smaller than 3 mm. Size of the lesion can influence the direction of error (shortening/elongation), but not its directionless magnitude.

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Purpose: This study aimed to investigate the effect of parents' fears of the SARS-CoV-2 pandemic on pediatric dental visits. Methods: In this cross-sectional study, conducted from July 2020 to August 2020, 500 parents of children who had visited pediatric dental offices were randomly selected. Parents were given a questionnaire containing 33 questions, which included three parts: (1) demographic characteristics, (2) dental problems scale, and (3) fear of SARS-CoV-2 scale. Based on the collected responses, the relationships between demographic factors, children's dental problems, and parents' fear of SARS-CoV-2 were evaluated. Results: The most common reason for visiting a pediatric dentist during the SARS-CoV-2 outbreak was tooth pain. Regarding parents' fear, 62.6% (n = 313) had moderate fear, 74.2% (n = 371) had a history of delays in referring to the dentist, and 54.4% (n = 272) had a history of moderate-to-severe dental pain. The fear scores in mothers were significantly higher than in fathers (P < 0.001). Parents of children with more pain and dental problems had higher scores on the fear scale (P = 0.017), (P = 0.016). Conclusion: Most pediatric dental visits during the SARS-CoV-2 outbreak were due to dental pain, and most parents had moderate-to-severe fear of their children being infected by SARS-CoV-2 through dental visits.

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BACKGROUND: This study was carried out to evaluate the effect of root canal filling on the bond strength of three intracanal posts in the primary incisors. MATERIALS AND METHODS: Sixty primary incisors were prepared and then divided into two groups (n = 30). The first group canals obturated with zinc oxide eugenol (ZOE) and Group 2 canals obturated with Metapex. Further, the two group categories were divided into three subgroups (n = 10): (1) short composite post (SCP), (2) glass fiber posts (GFPs) cemented with flowable composite, and (3) GFP with glass ionomer cement (GFP + GIC). The push-out test was performed with a universal testing machine. The results were statistically analyzed with two-way analysis of variance.(α = 0.05). RESULTS: The mean bond strength of the first group obturated with ZOE was lower than that of the second group obturated with Metapex (P = 0.046). Moreover, from a statistical point of view, in all three subgroups, the correlation of mean push-out bond strength between SCP and GFP coated with flowable composite was not substantial at P = 0.97. However, the mean bond strength of SCP was in fact significantly greater than that of the GFP coated with GIC since P = 0.034. CONCLUSION: Using ZOE resulted in the significant reduction of the mean bond strength of the intracanal posts when utilized in the primary anterior teeth. Likewise, SCP and GFP coated with flowable composite showed higher push-out bond strengths for restoring primary anterior teeth.

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OBJECTIVE: The aim of this study was to comparatively assess the fracture resistance of the cementum-extended and conventional composite fillings with or without intracanal composite posts in severely damaged deciduous incisors. MATERIALS AND METHODS: This in vitro study was performed on 60 extracted deciduous maxillary incisors that were randomly divided into four groups: Group 1: Composite filling (CF); Group 2: Composite filling with composite posts (CF + CP); Group 3: Composite filling extended 0.5 mm to cementum (ceCF); Group 4: Composite filling extended 0.5 mm to cementum with composite posts (ceCF + CP). The fracture resistance was assessed by exerting a progressively increasing load with a cross-head speed of 0.5 mm/min in a Universal Testing Machine. STATISTICAL ANALYSIS: Data were analyzed by SPSS-18 using one-way analysis of variance at α < 0.05. RESULTS: The mean fracture resistance (MFR) values of the experimental groups were 410.57 ± 139.44 N, 564.44 ± 92.63 N, 507.5 ± 76.37 N and 601.08 ± 96.04 N. A significant difference was found between the MFR of Groups 1 and 2, Groups 1 and 4 and Groups 3 and 4 (P < 0.05). CONCLUSION: A superior outcome was achieved by intracanal composite posts in both conventional and cementum-extended composite fillings.