Av Rajesh Ebenezar

Comparison of temperature rise in the pulp chamber with different light curing units: An in-vitro study

Aims/Objectives: This in vitro study was designed to measure and compare the temperature rise in the pulp chamber with different light curing units. Materials and Methods: The study was done in two settings-in-vitro and in-vivo simulation. In in-vitro setting, 3mm and 6mm acrylic spacers with 4mm tip diameter thermocouple was used and six groups were formed according to the light curing source- 3 Quartz-Tungsten-Halogen (QTH) units and 3 Light-Emitting-Diode (LED) units. For the LED units, three modes of curing like pulse-cure mode, fast mode and ramp mode were used. For in-vivo simulation, 12 caries free human third molar tooth with fused root were used. K-type thermocouple with 1 mm tip diameter was used. Occlusal cavity was prepared, etched, rinsed with water and blot dried; bonding agent was applied and incremental curing of composite was done. Thermal emission for each light curing agent was noted. Results: Temperature rise was very minimal in LED light cure units than in QTH light cure units in both the settings. Temperature rise was minimal at 6mm distance when compared to 3 mm distance. Among the various modes, fast mode produces the less temperature rise. Temperature rise in all the light curing units was well within the normal range of pulpal physiology. Conclusion: Temperature rise caused due to light curing units does not result in irreversible pulpal damage.

Application of a proanthocyanidin agent to improve the bond strength of root dentin treated with sodium hypochlorite

Aim: The objective of this study was to analyze the application of PA agent that improves the bond strength of root dentin treated with NaOCl. Materials and Methods: Group 1: root canals were irrigated using 0.9% isotonic saline as an irrigant (negative control); Group 2: root canals were irrigated using 5.25% NaOCl (positive control); Group 3: root canals were irrigated with 5.25% NaOCl followed by 10% sodium ascorbate for 10 minutes; Group 4: root canals were irrigated with 5.25% NaOCl followed by 5% PA for 10 minutes. All the canals were then coated with self-etch dentin bonding agent, filled with resin cement, stored for one day in water, and then cross sectioned into three slabs of 2-mm thickness that were prepared and tested for microtensile bond strength. Results: The results demonstrated that 5.25% NaOCl caused significant reduction (P<0.05) in the bond strength, but this can be reversed by 5% PA significantly more than the 10% sodium ascorbate.

Surface and mineral changes of enamel with different remineralizing agents in conjunction with carbon-dioxide laser

Aim: The aim of this study was to evaluate the surface/mineral changes on enamel before and after the application of acidulated phosphate fluoride (APF) gel, fluoride enhanced hydroxyapatite gel and propolis in conjunction with carbon-dioxide (CO 2 ) laser. Materials and Methods: Crowns of 40 human maxillary central incisors were collected and were divided into four groups of 10 each: Topical fluoride application only, topical fluoride application followed by CO 2 laser irradiation, CO 2 laser irradiation followed by topical fluoride application and CO 2 laser irradiation before and after topical fluoride application. The 10 crowns in each group was again sectioned into four equal parts of mesio-incisal, disto-incisal, mesio-cervical and disto-cervical sections rendering 40 samples in each group. Each group was again subdivided into four subgroups: Subgroup C - untreated enamel surface (control). Subgroup A - APF gel application, subgroup R - fluoride enhanced hydroxyapatite gel application and subgroup P - propolis application. The surface morphology of the test samples were analyzed by scanning electron microscopy and mineral changes by energy dispersion X-ray spectrophotometer. Results: Total mineral content is maximum in Group 4A (CO 2 laser irradiation before and after APF gel application) and calcium/phosphate ratio is highest in Group 4R (CO 2 laser irradiation before and after Remin-Pro application). Group 2A (APF gel application followed by CO 2 laser irradiation) has the maximum fluoride retention. Conclusion: Laser irradiation of enamel through a topically applied APF gel is effective in the prophylaxis and management of dental caries.

Effectiveness of calcium hydroxide plus points and chlorhexidine activ points against Enterococcus faecalis by agar diffusion test: An in‑vitro study

Aims/Objectives: The aim of this study was to evaluate the antimicrobial effectiveness of two intracanal medicaments and their combination against Enterococcus faecalis, which are commonly found in root canals. Materials and Methods: In this study, the antimicrobial effect of chlorhexidine activ points, calcium hydroxide plus points and combination of both points after 1 st day, 2 nd day, 3 rd day, 7 th day, and 14 th day were evaluated using agar diffusion test. Anti-bacterial activity as evidenced by inhibitory zones of clearance around the medicament was observed and diameters (in mm) measured. Results: Chlorhexidine activ points show the maximum inhibition against E. faecalis calcium hydroxide points alone and when combined with chlorhexidine shows the minimal antibacterial efficacy. Conclusion: Chlorhexidine activ points obtained the highest antimicrobial activity compared with other medicament and can be the medicament of choice.

An unusual occurrence of bilaterally geminated mandibular second premolars resulting in premolar molarization: A case report

Gemination refers to an attempt by a single tooth bud to divide, with a resultant formation of either a large tooth with a bifid crown or two completely divided teeth throughout the crown and root. This report describes a rare case of bilateral gemination of permanent mandibular second premolar tooth giving rise to molarization of premolars. The mesiodistal width of these teeth is similar to mandibular molars, but the cervicoocclusal width is lesser than that of the molar tooth. This paper also discusses the potential orthodontic, periodontal, and endodontic complications of premolar molarization.

Counteraction of reactive oxygen species and determination of antibacterial efficacy of proanthocyanidin and lycopene when mixed with calcium hydroxide and chlorhexidine mixture: An in vitro comparative study.

Aim: The objective of the study was to determine the neutralizing effect of proanthocyanidin (grape seed extract) and lycopene (tomato extract) on reactive oxygen species (ROS) generated by the mixture when used as an intracanal medicament. The study also evaluated the effect of proanthocyanidin and lycopene on the antibacterial efficacy of a mixture of chlorhexidine (CHX) and calcium hydroxide [Ca(OH)2] against Enterococcus feacalis. Materials and Methods: Four sample groups were prepared as follows. Group I: 2% CHX gluconate (control group) and group II: a mixture of 125 mg of Ca(OH)2 with 2% CHX gluconate solution. Group III was a mixture of 125 mg of Ca(OH)2 with 1 mL of 2% CHX gluconate solution and 1 mL of 5% proanthocyanidin solution and group IV, a mixture of 125 mg of Ca(OH)2 with 1 mL of 2% CHX gluconate solution and 1 mL of 5% lycopene solution. The groups were analyzed for ROS formation using the mass spectrometer (JEOL GC MATE II) immediately after preparation. The antibacterial property was evaluated by using agar diffusion method and the results were statistically analyzed using one-way analysis of variance (ANOVA) and Tukey-Kramer multiple comparison tests. Results: The peak value of 196.96 denotes ROS formation. Group II shows a higher peak value than other groups. Group IV shows a drastic reduction in the peak value. Group IV shows a drastic reduction in ROS formation when compared with group II, group III, and the control group. Antibacterial efficacy was higher in group IV, followed by group III, group II, and group I. Conclusion: Lycopene and proanthocyanidin reduce the ROS significantly by virtue of their antioxidant property. Lycopene shows more antioxidant property when compared with proanthocyanidin.

Maxillary lateral incisors with two canals and two separate curved roots

Variation in the roots and root canal anatomy seems to be the norm rather than an exception. For a successful endodontic treatment, a clinician should have a thorough knowledge of the internal and external dental anatomy and its variations. Maxillary lateral incisors usually exhibit single canal with a single root. In this case, clinical examination and radiographs clearly demonstrates the presence of two root canals with two separate curved roots. This case report emphasizes the need for attention during endodontic management of maxillary lateral incisors.

Effect of Chicken Egg Shell Powder Solution on Early Enamel Carious Lesions: An Invitro Preliminary Study

AIM To evaluate the remineralization potential of enamel surface lesion using chicken eggshell powder (CESP) solution. MATERIALS AND METHODS Ten freshly extracted un-erupted third molars decoronated at cement-enamel junction (CEJ) used in this study. Each decoronated tooth was sectioned to get 4 samples of enamel blocks such that 40 blocks were obtained which were then subjected to demineralization protocol and grouped as: Group 1-untreated group, Group 2-subsurface demineralization, Group 3-subsurface demineralization + 7 days CESP immersion, Group 4- subsurface demineralization + clinpro application. The samples were evaluated for X-ray fluorescence spectroscopy analysis, microhardness testing and atomic analyses using energy dispersive X-ray spectroscopy. The data were statistically analysed by using one-way ANOVA and Tukey - Kramer multiple comparison test. RESULTS X-ray Fluorescence spectroscopy shows Calcium concentration of 98% and 0.46% of phosphate. Group 4 (Clinpro) shows the highest efficacy in enhancing the remineralization followed by Group 3 (CESP). The results of atomic analyses showed that quantitative amounts of Ca weight % and P weight % is statistically greater for all the three groups except the demineralized group. CONCLUSION CESP with higher calcium content can remineralise enamel surface lesion.

Unusal canal configuration in maxillary and mandibular second molars

This clinical article describes three different case reports of maxillary and mandibular second molars with the unusual anatomy of single root with a single canal and their endodontic management. An unusual case of bilateralism is observed in the first two cases in the form of single-rooted second mandibular molars in both the quadrant of the same patient. The presence of maxillary second molar with single root and single canal in the third case is unusual.