Aim and objective: Evaluating dentinal cracks in root canal surface after biomechanical preparation using rotary file systems such as ProTaper Next, 2 Shape, and RaCe.
Materials and methods: Forty extracted human single canal mandibular premolars were decoronated perpendicular to the long axis of the tooth leaving roots (12 ± 1 mm) and then positioned centrally in a mold using acrylic resin. Roots were randomly divided into four main groups (n = 10) according to the nickel-titanium (Ni–Ti) rotary file system used in preparation as follows: Group I: Control group roots were left unprepared. Group II: Canals were prepared using Ni–Ti 2 Shape system up to TS2 file (#25/0.06). Group III: Canals were prepared using Ni–Ti ProTaper Next system up to X2 file (#25/0.06). Group IV: Canals were prepared using Ni–Ti RaCe system up to file (#25/0.06). Each root was sectioned horizontally using IsoMet saw into three sections as coronal, middle, and apical with a total of 120 sections and observed by stereomicroscope and scanning electron microscope to detect dentinal cracks.
Results: There are more dentinal cracks in the ProTaper Next group than in the 2 Shape, RaCe, and control groups as there was a statistically significant difference present (p < 0.05). There was no statistically significant difference between the apical, middle, and coronal sections (p = 0.536).
Conclusion: ProTaper Next group showed a high percentage of dentinal crack incidence followed by RaCe, 2 Shape, and control groups regardless of the root canal cross-section, and the highest percentage of dentinal crack incidence was in the apical third followed by middle and coronal thirds regardless of the Ni–Ti system.
Clinical significance: To evaluate Ni–Ti rotary system effect on dentinal crack incidence.
How to cite this article:
Chauhan U, Dewan R, Goyal NG. Comparative Evaluation of Bond Strength of Fifth, Sixth, Seventh, and Eighth Generations of Dentin Bonding Agents: An In Vitro Study. J Oper Dent Endod 2020; 5 (2):69-73.
Aim and objective: To evaluate and compare the shear bond strength of the fifth, sixth, seventh, and eighth generations of bonding agents.
Methods and materials: Forty freshly extracted premolars were selected and assigned into five groups: group I—fifth-generation bonding agent (SwissTEC SL Bond), group II—sixth-generation bonding agent (One Coat), group III—seventh-generation bonding agent (One Coat 7.0), group IV—eighth-generation bonding agent (One Coat 7 Universal), and group V—control group. With the help of an air rotor, the coronal dentin was exposed. The dentin bonding agents were applied, which was then followed by the placement of composite on surface which was earlier exposed. Shear bond strength testing was then done using universal testing machine.
Statistical analysis: Data were analyzed using SPSS version 21. The intergroup comparison was done using one way analysis of variance along with post hoc Tukey\'s test.
Results: Maximum shear bond strength was found in the eighth generation of bonding agent followed by the fifth, seventh, and lastly, the sixth generation (p <0.05).
Conclusion: The greatest shear bond strength to dentin was seen in the eighth generation of dentin bonding agent with a great advantage of fewer steps involved in the procedure as compared to other generations of dentin bonding agents.
Kishore G Bhat,
How to cite this article:
Singh M, Hiremath G, Bhat KG, Naik B. Evaluation and Comparison of the Effect of MTA, MTA Plus, Chitosan, and Their Conjugates on Cell Viability of Human Periodontal Ligament Fibroblasts: An In Vitro Study. J Oper Dent Endod 2020; 5 (2):74-78.
Aim and objective: The aim and objective of this in vitro study was to gauze the effect of MTA, MTA Plus, chitosan, and their conjugates on the cell viability of human pdl fibroblasts.
Materials and methods: A primary culture of human pdl fibroblasts was obtained. Materials used were MTA, MTA Plus, chitosan, and their conjugates. Methyl-thiazol-tetrazolium (MTT) colorimetric assay and Neutral Red assay were used to evaluate the cell viability of the root end filling materials after 24 hours of setting. Optical density of adherent stained biofilm was read at 570 nm using ELISA auto reader. Cell viability was evaluated as percentage of the negative control group, which represented 100% cell viability. Statistical analyses were done with one-way ANOVA and Tukey\'s post hoc test.
Results: Test indicates that there was no cell cytotoxicity seen in Group I (MTA) and Group II (MTA Plus), whereas mild cytotoxicity was seen in Group III (chitosan). However, in Group IV (MTA–chitosan conjugate) and Group V (MTA Plus–chitosan conjugate), proliferation of fibroblasts was seen.
Conclusion: Chitosan showed a synergistic effect with MTA and MTA Plus when used as a conjugate, as no cytotoxicity was seen in both the conjugates. In fact, there was proliferation of fibroblasts seen in Group IV (MTA–chitosan conjugate) and Group V (MTA Plus–chitosan conjugate).
Jambai S Sivakumar,
Anjaneya Shiva Prasad,
How to cite this article:
Sivakumar JS, Vaiyapuri R, Chandrasekaran S, Sivakumar A, Prasad AS, Mathimaraiselvan C. Comparative Evaluation of Antimicrobial Efficacy of Three Different Intracanal Medicaments against Candida albicans: An In Vitro Study. J Oper Dent Endod 2020; 5 (2):79-82.
Aim and objective: To evaluate and compare the antimicrobial efficacy of three different intracanal medicaments against Candida albicans by measuring the colony-forming units (CFU) at different time periods.
Materials and methods: Ninety premolar teeth extracted from mandible for orthodontic reasons were collected. The teeth in the experimental groups were decoronated to a standardized length. Canal patency was determined. Cleaning and shaping of the canals were done. Fungal colonies were suspended in 5 mL of Sabouraud Dextrose Broth (SDB) after being isolated for a day. Ten milliliters of fungal suspension of 0.5 McFarland solution was moved into each canal of the laminar flow hood under sterile conditions. Then, the teeth were divided into three investigational groups (n = 30) at random as well as subjected to the following intracanal medicaments: G1–Ca(OH)2, G2–Leder mix paste, G3–silver nanoparticles (SNP). The teeth were then put in sterile well plates, and they were secured with multiple layers of paraffin. After loading the various intracanal medicaments, all groups were redivided haphazardly into three uniform subgroups (n = 10) and then incubated for different time periods at 37°C temperature and 100% humidity.
On SDB agar, a 0.1 mL aliquot of the microbial suspension was plated, respectively. After 24 hours, 7, and 14 days of the incubation period, the number of CFU was assessed with a light microscope (400×) and recorded for groups 1, 2, and 3, respectively.
Results: There was a notable dissimilarity between the groups 1, 2, and 3 (p < 0.01). Group 3 was associated with a decreased amount of CFU at all three different meantime.
Conclusion: SNP alone was significantly better in its antimicrobial efficacy against C. albicans over the period of 24 hours, 7 days, and 14 days.
Background: White spot lesions appear clinically as a first sign of enamel caries, followed by cavitation when left untreated. Number of methods and agents are available to remineralize these lesions, which include resin infiltration and casein phosphopeptide-amorphous calcium phosphate (CPP–ACP) plus agent.
Aim and objective: The aim and objective of the in vitro study was to compare microhardness of initial enamel caries using two agents (Icon and CPP-ACP Plus).
Materials and methods: 120 extracted permanent maxillary central incisors were collected. All the samples were decoronated, and crown portions of 120 samples were inserted in acrylic resin block which was prestandardized. These samples were allocated randomly into control Group I (20) and experimental Group II (100). A 4 × 4 mm window was created on labial surfaces of 100 samples using acid-resistant nail varnish and then demineralized to produce white spot lesions for 4 days. Then, they were allocated into five groups randomly (Group I: normal/non-demineralized enamel (control), Group IIa: demineralized enamel, Group IIb: brushed with 0.25 g of non-fluoridated dentifrice (Meswak™), Group IIc: brushed with 0.25 g of non-fluoridated dentifrice + CPP ACP plus, Group IId: ICON DMG™ resin infiltration technique, Group IIe: ICON DMG™ resin infiltration technique + brushed with 0.25 g of non-fluoridated dentifrice) and treated with the respective remineralizing agents for 1 month. Samples of all the groups were then subjected to microhardness test.
Results: The microhardness value of Group IId was significantly (p < 0.001) high when compared to other experimental groups.
Conclusion: Resin infiltration technique showed enhancement in the microhardness of initial enamel caries lesions compared to CPP-ACP plus application.
Clinical significance: Resin infiltration technique is a microinvasive approach for increasing the microhardness of hypoplastic enamel. This may decrease need of laminates or other full coverage restorations for such teeth.
Malli Sureshbabu Nivedhitha,
Stem cells, scaffolds, and growth factors, each of which possesses unique biological capabilities, constitute what is known as the tissue engineering triad. Recently, regenerative endodontics has emerged as a new field that deals with the rejuvenation of the pulp–dentin complex in necrotic immature permanent teeth, regeneration of bone, periodontal ligament and cementum in cases with large periapical lesion, and regeneration of periodontal tissue and bone in endo-perio lesions. Scaffolds play a major part in the formation of the extracellular matrix by providing support to cells to adhere, grow, and differentiate. In this review, four major categories of scaffolds (autologous platelet concentrates, nanofibrous scaffolds, injectable scaffolds, and bioactive molecule carrier systems) used in regenerative endodontics have been discussed in detail.
Aim and objective: The aim of this study is to manage periapical lesions of endodontic origin without invasive surgery.
Background: Though root canal instrumentation along with irrigation greatly reduces the number of bacteria in the infected canals, it is difficult to obtain complete disinfection in all cases. The use of intracanal medicaments helps in reducing or inhibiting the growth of microbes that are left behind after cleaning and shaping to prevent reinfection. This will ensure lesion reduction or resolution.
Case descriptions: Four cases have been presented with periapical lesions that were all accessed, cleaned, and shaped in the first visit, followed by Metapex placement in the next visit. After a 3-month interval, when the lesions healed well, obturation was done.
Clinical significance: For the treatment of periapical lesions, nonsurgical therapy should be considered as first-line treatment option as it proves to be a more conservative approach.
Various resin-bonded bridges are available and documented in the literature for many years as both temporary and permanent restorations for single missing anterior tooth and posterior tooth. All of the resin-bonded fixed partial prostheses require some amount of tooth preparation, and as we are practicing more conservative approaches toward restoring single missing teeth, a CAROLINA BRIDGE, which requires no significant tooth preparation making it an excellent choice as an interim fixed prosthesis. The success of this prosthesis completely depends upon the interproximal surface area.