Interfacial assessment of cention forte vs. equia forte and two forms of calcium silicate cements at two time intervals.

AIM: Assessment of interfacial gaps and mechanical impact of the materials layering between Cention Forte and Equia Forte restorations with two forms of Calcium Silicate Cements (CSCs) at the interfacial surface at two-time intervals. METHODOLOGY: Six groups of 72 primary molars were categorized by restorative material type and CSCs: Cention Forte(C), Cention Forte without primer (Cx), and Equia Forte (EQ). All were applied over MTA Angelus powder (M) or Bio-C Repair putty (P). Restorative materials were applied immediately (subgroup A) or delayed (Subgroup B). SEM was used to detect interface gaps. EDX measured element migration from the interface at specific distances. Vickers Microhardness Tester assessed microhardness. RESULTS: Regarding SEM, there were no gaps between CSCs interfaces of both types (Powder and Putty) with all restorations at two-time intervals. Microhardness, there was a statistically nonsignificant difference between subgroups A & B in all groups except at 200 µm in the Cention groups (subgroup A) was significantly lower than (subgroup B) (P = 0.002, 0.03) respectively. At 400 µm in the MTA Angelus powder Group Cx, subgroup A was significantly higher than subgroup B (P = 0.003*). While Bio-C Repair putty in Group EQ (subgroup A) was significantly higher than (Subgroup B) (P < 0.0001*). CONCLUSIONS: The delayed application of Cention Forte over two types of CSCs is useful in getting the maximum HV and, in turn, the long survival rate of the filling. Immediate application of Cention Forte without primer is better over both types of CSCs. The delayed application of Equia Forte over MTA angelus powder is more considerable.

Efficacy of using chitosan and chitosan nanoparticles as final irrigating solutions on smear layer removal and mineral content of intraradicular dentin.

Background: This study evaluated the effect of using chitosan, nano-chitosan, and ethylenediaminetetraacetic acid (EDTA) as final irrigating solutions on smear layer cleanliness and Ca/P ratio of dentin. Methodology: Forty-eight decoronated human single-rooted teeth were used. They were divided randomly into four groups (n = 12) based on the final irrigating solution used as follows: (a) control group (IA; n = 6) normal saline, (IB; n = 6) were left unprepared; group II - 0.2% chitosan; group III - 0.2% nano-chitosan; and group IV - 17% EDTA. Samples were prepared using ProTaper Next and irrigated with 2.6% NaOCl 5 ml after each instrument using 31-gauge needle. Final rinse was used 5 ml/3 min according to the assigned group. The specimens were prepared for evaluation. Results: Best smear layer removal was observed in group IV. No statistically significant differences (P > 0.05) were observed between the experimental groups (II, III, and IV) coronally; however, a statistically significant difference (P < 0.05) was observed between groups II and IV at middle and apical thirds. Intragroup comparison showed that apical third exhibited the highest mean smear layer score among all experimental groups. The highest mean Ca/P ratio was in the 0.2% nano-chitosan group, while the highest calcium loss was in the 17% EDTA group. Conclusions: 17% EDTA is a potent chelating agent that can successfully remove the smear layer but compromises the Ca/p ratio of dentin. However, 0.2% chitosan and its nanoparticles have comparable chelating effects and induce remineralization of the root canal dentin.

Canal Transportation and Centring Ratio of Paediatric vs Regular Files in Primary Teeth.

BACKGROUND: During mechanical preparation of the primary root canal, the original anatomy of the tooth should be preserved and the instrument should be perfectly balanced centrally into the canal space for reducing the probability of canal transportation. The aim of this research was to compare canal transportation and canal centring ability in primary root canals using ProTaper Next (Dentsply Mailfair,), AF baby (Fanta), and Kidzo Elephant (Endostar, Poldent Sp.) files. MATERIALS AND METHODS: Eighteen root canals were randomly divided into 3 experimental groups (n = 6 in each group). Instrumentation was performed using ProTaper Next, Fanta AF baby, and Kidzo Elephant files in groups 1, 2, and 3, respectively. During the instrumentation procedure, the irrigation of 2 mL of 1.5% sodium hypochlorite between each file was done, followed by 5 mL of 17% ethylenediaminetetraacetic acid as a final irrigating solution. Cone-beam computed tomography images were obtained before and after instrumentation. Each group was evaluated for transportation and centring ratios. RESULTS: On comparing all the tested groups within each root canal level canal transportation, the results revealed a statistically nonsignificant difference in the buccolingual direction (P > 0.05). Meanwhile, in the mesiodistal direction, group 1 showed a statistically highly significant difference compared to groups 2 and 3 at the cervical level (P < .01). However, in both middle and apical root canal levels, there was a statistically nonsignificant difference amongst all groups (P > 0.05). Regarding the centring ability comparison of the 3 groups within each root canal level, there was a statistically nonsignificant difference amongst all groups (P > 0.05) in both buccolingual and mesiodistal directions. CONCLUSIONS: The ProTaper Next regular rotary file and the paediatric rotary files showed no difference in canal transportation and centring ability in the buccolingual direction, while in the mesiodistal direction at the cervical root canal level, the ProTaper Next showed high transportation liability.