Comparative Analysis of the Particle Size and Shape of Commercially Available Mineral Trioxide Aggregates and Portland Cement: A Study with a Flow Particle Image Analyzer
Takashi Komabayashi, DDS, PhD, Larz S.W. Spångberg, DDS, PhD
The aim of this study is to characterize the particle size distribution and circularity of various Mineral Trioxide Aggregates (MTA) (ProRoot MTA/ MTA Angelus/Gray and White) and Portland cements with effective size ranges of 1.5−160 μm using a flow particle analyzer (Sysmex FPIA-3000, Kobe, Japan).Cumulative percentage of particles between 6 and 10 μm were, 65, 73, 48, 53, and 70 %, for Gray ProRoot MTA, White ProRoot MTA, Gray MTA Angelus, White MTA Angelus, and Portland cement, respectively. ProRoot MTA contains fewer large particles than MTA Angelus. MTA Angelus contains a higher number of small particles than ProRoot MTA. White MTA contains smaller particles with a narrower range of size distribution than Gray MTA. MTA Angelus particles have relatively low circularity and wide size distribution and are less homogeneous than ProRoot MTA.
Setting Expansion of Gray and White Mineral Trioxide Aggregate and Portland Cement
Buffy Storm, DDS, MS, Frederick C. Eichmiller, DDS, Patricia A. Tordik, DMD, Gary G. Goodell, DDS, MS, MA
One possible reason for the sealing ability of mineral trioxide aggregate (MTA) is its slight expansion upon setting. Both gray mineral trioxide aggregate (GMTA) and white mineral trioxide aggregate (WMTA) are composed of approximately 75% Portland cement (PC). WMTA differs from GMTA in its lower content of tetracalcium aluminoferrite. This difference in composition may affect setting expansion. The purpose of this study was to compare the hydroscopic linear setting expansions of GMTA, WMTA, and PC with a new device. Materials were mixed with water, placed into a cylindrical mold, and covered with sterile water or Hank’s balanced salt solution (HBSS). Expansion changes were measured by using a linear variable displacement transformer dilatometer. One-way analysis of variance and post hoc tests (α = 0.05) showed the mean expansion at 24 hours was 1.02% for GMTA, 0.29% for PC, and 0.08% for WMTA in water immersion and 0.68% for GMTA and 0.11% for WMTA in HBSS immersion. GMTA expanded significantly more than WMTA in either water or HBSS immersion.
Quantification of Neural Protein in Extirpated Tooth Pulp
Curt A. Warren, DDS, LeePeng Mok, MS, Sharon Gordon, DDS, MPH, PhD, Ashraf F. Fouad, DDS, MS⁎, Michael S. Gold, PhD
Because the pulp tissue extirpated during root canal procedures might serve as a valuable resource with which to assess underlying mechanisms of persistent pain, we sought to determine whether standard Western blotting techniques could be used to quantify neural proteins in pulp extirpated from teeth with irreversible pulpitis. Pulp harvested from healthy intact teeth extracted for orthodontic reasons was used for comparison. The neural marker PGP9.5 was detectable in all samples tested. A membrane enrichment protocol enabled detection of even low abundance, high molecular weight proteins such as the sodium channel α-subunit NaV1.8. Importantly, it was possible to quantify a ∼6-fold increase in the relative density of NaV1.8 in inflamed pulp compared with control pulp. Our results suggest that it should be possible to use extirpated tooth pulp to validate mechanisms of persistent pain implicated in preclinical studies as well as evaluate the therapeutic efficacy of novel antinociceptive interventions.
Effect of Irrigants and Cementum Injury on Diffusion of Hydroxyl Ions through the Dentinal Tubules
Sherma Saif, DMD, MS, Clifton M. Carey, PhD, Patricia A. Tordik, DMD, Scott B. McClanahan, DDS, MS
This study measured hydroxyl ion diffusion through dentinal tubules into a bathing solution. Eighty single-canal, instrumented teeth were divided into 8 groups. Control groups 1 and 3 were irrigated with 10 mL 0.9% saline and 10 mL 6% sodium hypochlorite (NaOCl), respectively. Control groups 5 and 7 were irrigated with 3 mL and 1 mL 17% ethylenediaminetetraacetic acid (EDTA) and then 10 mL 6% NaOCl, respectively. Experimental groups 2, 4, 6, and 8 were irrigated as groups 1, 3, 5, and 7, followed by placement of calcium hydroxide (Ca(OH)2) into canals. Bathing solution pH was recorded for 30 days, a cementum defect was made, and then pH was recorded for another 30 days. With a paired difference test, average pH during steady state was statistically different and higher after the defect (P < .001). With Tukey multiple comparisons, post-defect pH for group 6 was found to be significantly greater (P < .01) than in other groups. This study indicated final canal irrigation with 3 mL 17% EDTA and 10 mL 6% NaOCl before Ca(OH)2 placement allowed the greatest hydroxyl ion diffusion to the root surface.
Significance of Moist Root Canal Dentin with the Use of Methacrylate-based Endodontic Sealers: An In Vitro Coronal Dye Leakage Study
Osvaldo Zmener, DDS, Dr Odont⁎, Cornelis H. Pameijer, DMD, MScD, DSc, PhD, Susana Alvarez Serrano, DDS, Mercedes Vidueira, DDS, Ricardo L. Macchi, DDS, Dr Odont
This in vitro study compared the effect of different levels of moisture of root canals, from none to wet, on the coronal seal after filling with resin-coated gutta-percha cones/EndoRez [RGPC/ER (groups 1–4)], Resilon/Epiphany [RE/EP (groups 5–8)], and gutta-percha/Grossman‘s cement [GP/G (groups 9–12)]. The length of 76 single-rooted extracted human teeth was standardized to ∼17 mm. After instrumentation with size 10 K-Files, #2 and #3 Gates Glidden burs, and preparation to the working length with K-Type files, the smear layer was removed with 17% ethylenediaminetetraacetic acid followed by flooding with distilled water. On the basis of similarities of canal shape determined by x-rays, roots were assigned to the groups (n = 5 per group) and treated according to one of the following protocols. (I) ETOH: excess distilled water was removed with paper points followed by dehydration with 95% ethanol; (II) PAPER POINTS: the canals were blot-dried with paper points with the last one appearing dry; (III) MOIST: the canals were dried with low vacuum by using a luer adapter for 5 seconds followed by 1 paper point for 1 second; and (IV) WET: the canals remained totally flooded. The roots were then filled with one of the obturation systems outlined above. The teeth were coated with 2 layers of nail varnish and 1 layer of sticky wax, except for the coronal access. In addition, positive and negative controls were added. After immersion in 2% methylene blue dye for 7 days, the samples were embedded in clear orthodontic resin and cross-sectioned at 0.5-mm intervals along the length of the roots. Dye penetration was evaluated by an independent investigator with a stereomicroscope at 40× magnification. The results indicated that dye leakage was affected by the degree of moisture. All materials evaluated showed some evidence of dye penetration, however, root canals filled with resin-coated gutta-percha/EndoRez and Resilon/Epiphany demonstrated significantly less leakage (P < .05) when moist conditions II and III were present.
Use of Cone-Beam Computed Tomography to Identify Root Canal Systems In Vitro
Ryan P. Matherne, DDS, Christos Angelopoulos, DDS, MS, James C. Kulild, DDS, MS, Daniel Tira, PhD
This study investigated the use of cone-beam computed tomography (CBCT) as a diagnostic tool for identifying root canal systems (RCSs) when compared with images obtained by using charged coupled device (CCD) and photostimulable phosphor plate (PSP) digital radiography in vitro. Seventy-two extracted teeth were exposed with CCD, PSP, and CBCT radiography. Specimens included 24 maxillary molars, mandibular premolars, and mandibular incisors each. Tooth-type selections were based on the greater possibility of multiple RCSs. Three board-certified endodontists evaluated CCD and PSP images to determine the number of RCSs. CBCT images were used to establish “ground truth” for the comparisons and were evaluated by a board-certified oral and maxillofacial radiologist who determined the number of RCSs. Descriptive statistical analysis revealed that the endodontists consistently agreed among themselves. When compared with CBCT evaluation, the endodontists, on average, failed to identify 1 or more RCSs in 41% of the teeth with CCD and 40% of the time with PSP. CBCT evaluations identified an average of 3.58 RCSs per maxillary molar, 1.21 per mandibular premolar, and 1.5 per mandibular incisor. Evaluation of CCD images demonstrated an average number of 1.0 RCSs per mandibular incisor, 1.0 per mandibular first premolar, and 3.1 per maxillary molar. Evaluation of PSP images demonstrated an average number of 1.3 RCSs per mandibular incisor, 1.1 per mandibular first premolar, and 3.0 per maxillary molar. In summary, endodontist evaluators with either CCD or PSP methods failed to identify at least 1 RCS in approximately 4 of 10 teeth, which can result in a less optimal healing outcome if a missed RCS is left uninstrumented and unobturated.
Quantitative and Qualitative Elemental Analysis of Different Nickel–Titanium Rotary Instruments by Using Scanning Electron Microscopy and Energy Dispersive Spectroscopy
Hani F. Ounsi, DCD, DESE, MSc, FICD, Thakib Al-Shalan, DDS, MSc, PhD, Ziad Salameh, DDS, MSc, FICD, Simone Grandini, DDS, MSc, PhD, Marco Ferrari, DDS, MSc, PhD
This study was designed to determine if the alloy composition shares an influence with the geometric design on the physical behavior of nickel-titanium rotary endodontic instruments. ProTaper, HERO, and K3 files were selected. After sterilized and cleaning with alcohol, surface analysis was performed using energy dispersive spectroscopy. Measurements were performed on the active part and on the shank. SEM images of fractured instruments were also obtained and assessed. All three types of instruments were composed mainly of Nickel (54.3%, SD ± 0.8) and Titanium (45.2%, SD ± 0.9). SEM images revealed similar aspect with the presence of Kirkendall voids regularly distributed in the alloy. The results indicate that the difference in properties and behavior of these three endodontic rotary shaping instruments is solely related to the respective geometric characteristics of the instrument design.
Profiling of Radicular Cyst and Odontogenic Keratocyst Cytokine Production Suggests Common Growth Mechanisms
Makoto Hayashi, DDS, PhD, Takafumi Ohshima, DDS, PhD, Mitsuhiro Ohshima, DDS, PhD, Yoko Yamaguchi, BS, Hirofumi Miyata, DDS, PhD, Osamu Takeichi, DDS, PhD, Bunnai Ogiso, DDS, PhD⁎†, Koichi Ito, DDS, PhD, Arne Östman, PhD, Kichibee Otsuka, DDS, PhD
The aim of this study was to compare the cytokine expression profiles of cyst fluids (CFs) and tissue culture supernatants (SUPs) from 7 radicular cysts (RCs) and 7 odontogenic keratocysts (OKCs) by using Human Cytokine Antibody Array to identify the specific cytokines involved in formation and expansion of RCs and OKCs, respectively. There were significant differences in relative expression levels of IL-1β, MCP1, MIP1β, FGF-9, GDNF, HGF, IGFBP-3, Ang, IP-10, MIF, OPG, and TGF-β2 between RC-CF and OKC-CF (P < .05). On the other hand, the cytokine expression patterns of RC-SUP (HGF, IL-8, NAP-2, IL-6, TIMP-1 and 2, GRO, IP-10, and Ang) were similar to those of OKC-SUP. Only the relative expression level of GRO differed between RC-SUP and OKC-SUP (P < .05). The similarities of cytokine production by tissue cultures derived from RC and OKC indicate that the expansion mechanisms of RC and OKC might involve similar biologic mechanisms other than infection.
Analysis of Mineral Trioxide Aggregate Surface when Set in the Presence of Fetal Bovine Serum
Mark C. Tingey, DDS, Peter Bush, BS, Ming Shih Levine, DDS, MS
Understanding the chemical and physical characteristics of set mineral trioxide aggregate (MTA) surface can provide insight into its bioactivity. The purpose of this study was to describe the surface chemistry and morphology of gray and white MTA set in the presence of fetal bovine serum (FBS). Eight MTA blocks were prepared: four set in the presence of water and four in FBS. The surface morphologic characteristics were studied via scanning electron microscopy. The surface chemical composition of the set cement was investigated by energy dispersive x-ray spectroscopy and x-ray fluorescence. No difference was found between gray and white MTA when set in the same solution. However, MTA/FBS and MTA/water present differing surface morphology and chemical distributions. When set in FBS, MTA’s surface had a homogenous distribution of chemicals and a relatively smooth globular appearance. MTA/water’s surface was biphasic, containing large hexagonal crystalline plates composed of calcium embedded in a pool of globular crystals.
Comparison of Rotary Instrumentation and Continuous Wave Obturation to Reciprocating Instrumentation and Single Cone Obturation with a Hydrophilic Sealer
Paul S. Sahni, DMD, MSD, Cecil E. Brown, DDS, MS, Joseph J. Legan, DDS, MS, B. Keith Moore, PhD, Mychel M. Vail, DDS, MSD
This in vitro study compared the effectiveness between ProFile 29 Series rotary system followed by continuous wave obturation and the Endo-Eze system. Thirty-six human mandibular canine and premolar teeth were randomly separated into 2 groups of 18. Each tooth was embedded in resin and sectioned at 2, 6, and 12 mm from the apex and viewed under the scanning electron microscope at 50–150× magnification. The percentages of canal space occupied by gutta-percha, sealer, debris, and voids were measured and analyzed with Image J software. Results were calculated by using an analysis of variance model with fixed effects for method, distance, and distance interaction. Repeatability of measurements and intraclass correlation coefficients were calculated. These results demonstrated that obturation with the continuous wave technique achieved significantly more gutta-percha occupying the canal space than the Endo-Eze system. Under the conditions of this study, the continuous wave technique was less likely to exhibit voids than the Endo-Eze technique. Furthermore, neither the Profile Series 29 nor the Endo-Eze system cleaned and shaped elliptical canals consistently.
Microleakage of Accelerated Mineral Trioxide Aggregate and Portland Cement in an In Vitro Apexification Model
Seong-Tae Hong, DDS, MSD, Kwang-Shik Bae, DDS, PhD, Seung-Ho Baek, DDS, PhD, Kee-Yeon Kum, DDS, PhD, WooCheol Lee, DDS, PhD
The purpose of this study was to evaluate the microleakage of accelerated mineral trioxide aggregate (MTA) and Portland cement by flow porometry analysis in an in vitro apexification model. Sixty-four single-rooted, extracted teeth were divided into 4 groups (group 1, MTA; group 2, MTA with accelerator; group 3, Portland cement; and group 4, Portland cement with accelerator). In an in vitro apexification model, MTA or Portland cement mixed with or without 10% CaCl2 was condensed to 2-mm thickness. The negative control group (n = 4) had the apical foramen sealed with epoxy resin. The maximum and mean flow pore diameters of the samples were tested by capillary flow porometry at 90 minutes and 48 hours after obturation. The addition of accelerator significantly reduced the maximum pore diameters of MTA and Portland cement at the initial setting phase. After 48 hours of obturation, the maximum and mean flow pore diameters of the accelerated samples were significantly reduced compared with the normal samples. There was no statistically significant difference in the maximum pore diameter of MTA and Portland cement between the measurements at 90 minutes and 48 hours. The results imply that the addition of accelerator into MTA or Portland cement can be useful in a one-visit apexification by reducing microleakage even in an early setting time.
Correlation between the Expression of c-Fos and Osteoclasts in Induced Periapical Lesions in Rats
Jing Yang, DDS, Bin Peng, DDS, PhD
The experiment was undertaken to observe the correlation between the expression of c-Fos and osteoclasts in experimental periapical lesions in rats. Apical periodontitis was induced in Wistar rats by occlusal exposure of the pulp of their mandibular first molars. After the exposure, 25 Wistar rats were killed on days 0, 7, 14, 21, and 28. The jaws that contained the first molar were obtained and routinely prepared for immunohistochemistry and enzyme histochemistry. A few c-Fos–positive cells and osteoclasts could be observed on day 7, and both climaxed on day 14. In the 21-day and 28-day samples, the expression of c-Fos decreased, and fewer osteoclasts could be observed. From day 7 to day 28, a significant positive correlation was found between the expression of c-Fos and osteoclasts. These findings demonstrated that c-Fos might be associated with the differentiation of osteoclasts in the periapical lesions.
Evaluation of Mineral Trioxide Aggregate and Calcium Hydroxide Cement as Pulp-capping Agents in Human Teeth
Maria de Lourdes R. Accorinte, DDS, MS, PhD, Roberto Holland, DDS, MS, PhD, Alessandra Reis, DDS, PhD, Marcelo C. Bortoluzzi, DDS, PhD, Sueli S. Murata, DDS, MS, PhD, Eloy Dezan Jr, DDS, MS, PhD, Valdir Souza, DDS, MS, PhD, Loguercio Dourado Alessandro, PhD
This study evaluated the histomorphologic response of human dental pulps capped with mineral trioxide aggregate (MTA) and Ca(OH)2 cement (CH). Pulp exposures were performed on the occlusal floor of 40 human permanent premolars. After that, the pulp was capped either with CH or MTA and restored with composite resin. After 30 and 60 days, teeth were extracted and processed for histologic exam and categorized in a histologic score system. The data were subjected to Kruskal-Wallis and Conover tests (α = .05). All groups performed well in terms of hard tissue bridge formation, inflammatory response, and other pulpal findings. However, a lower response of CH30 was observed for the dentin bridge formation, when compared with MTA30 and MTA60 groups. Although the pulp healing with calcium hydroxide was slower than that of MTA, both materials were successful for pulp capping in human teeth.
Interferon-gamma, Interleukin-10, Intercellular Adhesion Molecule-1, and Chemokine Receptor 5, but not Interleukin-4, Attenuate the Development of Periapical Lesions
Andiara De Rossi, DDS, MSc, Lenaldo B. Rocha, DDS, PhD, Marcos A. Rossi, MD, PhD
This study examines the role of Th1 (interferon-gamma [IFN-γ]) and Th2 (interleukin-4 [IL-4] and IL-10) cytokines, an intercellular adhesion molecule (ICAM-1), and a chemokine receptor (CCR5) in the pathogenesis of periapical lesions at different stages of development in knockout mice. For lesion induction, the first molar was opened and inoculated with 4 bacterial strains and left open to the oral environment. After 21 and 42 days, the IFN-γ, IL-10, ICAM-1, and CCR5 knockout animals presented periapical lesions larger than those of wild-type animals. There was no statistically significant difference between periapical lesions induced in IL-4 knockout and wild-type animals during the periods evaluated. Our findings suggest an important role for IFN-γ, IL-10, ICAM-1, and CCR5 in the pathogenesis of experimentally induced pulp infection and bone destruction as endogenous suppressor of periapical lesion development, whereas IL-4 appears to present a nonsignificant effect on periapical lesion modulation.
Longitudinal Co-site Optical Microscopy Study on the Chelating Ability of Etidronate and EDTA Using a Comparative Single-tooth Model
Gustavo De-Deus, DDS, MS, Matthias Zehnder, Dr med dent, PhD, PD, Claudia Reis, DDS, MS, Sandra Fidel, DDS, MS, PhD, Rivail Antonio Sergio Fidel, DDS, MS, PhD, João Galan Jr, DDS, MS, PhD, Sidney Paciornik, DsC
In the present study the smear layer dissolution kinetics of 18% etidronate (HEBP), 9% HEBP, and 17% ethylenediaminetetraacetic acid (EDTA) on human dentin were quantitatively and longitudinally analyzed by using a single-tooth comparative model. Coronal dentin disks were prepared from 3 maxillary human molars. A standardized smear layer was produced on the pulpal side of each disk. The smear layer–covered surface was divided into 3 similar areas. Each of these was then exposed to 1 of the 3 irrigants under investigation, whereas the others were covered with adhesive tape. Co-site image sequences of the areas under investigation were obtained after several cumulative demineralization times. Sixteen images were obtained from each dentin area of each tooth for each experimental time at 1000× magnification. An image processing and analysis sequence measured sets of images, providing data of area fraction for thousands of tubules over time and allowing us to quantitatively follow the effect of the chelating substances. The Kruskal-Wallis H test and Dunn multiple comparison test were used to analyze the data. Overall, it can be concluded that the demineralization kinetics promoted by both 9% HEBP and 18% HEBP were significantly slower than those of 17% EDTA (P < .05). In addition, the single-tooth model is advantageous over the first co-site optical microscopy dentin assessments when different chelator solutions are compared.
Wound Healing Process of Injured Pulp Tissues with Emdogain Gel
Hikaru Kaida, DDS, Takafumi Hamachi, DDS, PhD, Hisashi Anan, DDS, PhD, Katsumasa Maeda, DDS, PhD
This study aimed to investigate the wound healing process of injured pulp tissues with Emdogain gel (EMD). Pulpotomy was performed for the first molars of the mandibles in rats. EMD or Vitapex (VIT)-containing calcium hydroxide was applied to the exposed pulp tissues. The treated teeth were extracted after 7, 14, and 28 days and prepared for histologic examination. In the VIT-treated group, the number of interleukin-1β (IL-1β)–expressing macrophages initially increased, followed by that of transforming growth factor–β1 (TGF-β1)–expressing macrophages. The number of cells expressing bone morphogenetic proteins (BMPs) gradually increased with reparative dentin formation. Meanwhile, in the EMD-treated group, cells expressing IL-1β or TGF-β1 were few. However, the number of BMP-expressing cells, partly macrophages, increased in the early phase, and large amounts of reparative dentin were observed. This study demonstrated that different healing processes existed for EMD and VIT. BMP-expressing macrophages might play important roles in reparative dentin formation.
Root Resorption Associated with Mandibular Bone Erosion in a Patient with Scleroderma
Maria Antonia Zancanaro de Figueiredo, BDS, PhD, Jose Antonio Poli de Figueiredo, BDS, MSc, PhD, Stephen Porter, MD, PhD, FDS RCS, FDS RCSE
A rare feature of mandibular bone erosion and external apical resorption of a mandibular left third molar (tooth #17) in a patient with scleroderma is described. Scleroderma is characterized by vascular and fibrous changes of the mucocutaneous surfaces and viscera caused by immunologically mediated connective tissue disorders. A dental panoramic tomogram of the patient revealed notable erosion of the left ramus, the inferior border of the mandible, and the left coronoid process. Resorption of the distal root of the tooth #17 was notable, coincident with the mandibular erosive process, and such association has not yet been reported. The report details the possible cause of this unusual presentation of tooth root resorption. The increased physical pressure of the tight facial mucocutaneous tissues from the scleroderma is likely to have participated in the resorptive process.
ProRoot MTA, MTA-Angelus and IRM Used to Repair Large Furcation Perforations: Sealability Study
Ahmed Abdel Rahman Hashem, BDS, MSc, PhD, Ehab E. Hassanien, BDS, MSc, PhD
The ability of two mineral trioxide aggregate (MTA) compounds and Intermediate Restorative Material (IRM) to seal large furcation perforations were evaluated using a dye-extraction leakage method. The furcation perforations were repaired with and without the use of internal matrix before placement of repair material. Eighty extracted human mandibular first molars were divided into positive (n = 10), negative (n = 10), and three experimental groups (n = 20) according to the repair material used. Each experimental group was divided into two subgroups (n = 10) according to whether internal matrix was used or not. Dye leakage was tested from an orthograde direction, and dye extraction was performed using full concentration nitric acid. Dye absorbance was measured at 550 nm using spectrophotometer. ProRoot MTA (Maillfer, Dentsply, Switzerland) with and without internal matrix and MTA-Angelus (Angelus, Londrina, PR, Brazil) with internal matrix showed the least dye absorbance. IRM (Caulk, Dentsply, Milford, DE) without internal matrix showed the highest dye absorbance. IRM with internal matrix and MTA-Angelus without internal matrix had insignificant difference and came at intermediate level between the other groups.
New Portland Cement–based Materials for Endodontics Mixed with Articaine Solution: A Study of Cellular Response
Maria Giovanna Gandolfi, MBio, DSc, PhD, Francesca Perut, MBio, DSc, PhD, Gabriela Ciapetti, MBio, DSc, PhD, Romano Mongiorgi, MGeol, DSc, Carlo Prati, MD, DDS, PhD
The biocompatibility of innovative tetrasilicate cements proposed for root-end filling restorations was tested. White ProRoot-MTA and AH Plus were used as control. The new cements were mixed with a local anesthetic solution (4% articaine) to form a paste. Human osteoblast-like cells Saos-2 were challenged in short-term cultures (72 hours) with solid materials and with material extracts prepared in culture medium. Cell growth and viability, cellular attachment, and morphologic features were assessed to verify cell/material interactions. No acute toxicity was exerted by the experimental cements in the assay systems. On solid samples Saos-2 adhered and proliferated on all the experimental cements and on MTA. The ultrastructural findings revealed that Saos-2 were able to adhere and to spread. The maintenance of the osteoblastic phenotype on the innovative cements was confirmed by the alkaline phosphatase assay. All experimental cements prepared with articaine supported the growth of bone-like cells, showing suitable properties to be used as canal sealers and root-end filling materials.
Endodontic Management of a Mandibular Second Premolar with Four Roots and Four Root Canals with the Aid of Spiral Computed Tomography: A Case Report
Gurmeet Singh Sachdeva, BDS, Suma Ballal, MDS, Velayutham Gopikrishna, MDS, Deivanayagam Kandaswamy, MDS
Aberrations in the root canal anatomy are a commonly occurring phenomenon. A thorough knowledge of the basic root canal anatomy and its variations is necessary for successful completion of the endodontic treatment. Mandibular second premolars usually have a single root and a single root canal. The incidence of three separate roots itself in this tooth is quite rare, and the presence of four separate roots and four distinct root canals has never been reported in literature so far. The use of spiral computed tomography scan in this rare case greatly contributed towards making a confirmatory diagnosis and successful nonsurgical endodontic management thereafter.
Evaluation of Morinda citrifolia as an Endodontic Irrigant
Peter E. Murray, BSc(Hons), PhD, Romi M. Farber, DDS, Kenneth N. Namerow, DDS, Sergio Kuttler, DDS, Franklin Garcia-Godoy, DDS, MS
The purpose of this study was to compare the in vitro effectiveness of Morinda citrifolia juice (MCJ) with sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHX) to remove the smear layer from the canal walls of endodontically instrumented teeth. Sixty extracted, single-rooted, mature, permanent, human premolar teeth with a single canal were inoculated with Enterococcus faecalis at 37°C in a CO2 atmosphere for 30 days. The teeth were randomly allocated to 6 treatment groups; the pulp chamber was accessed, cleaned, and shaped by using ProTaper and ProFile rotary instrumentation to a size 35. During instrumentation the irrigation was provided by MCJ, NaOCl, CHX, MCJ/CHX, followed by a final flush of 17% ethylenediaminetetraacetic acid (EDTA). MCJ irrigation was also followed by a final flush of saline, and saline irrigation was also used as a negative control. The teeth were then processed for scanning electron microscopy, and the removal of smear layer was examined. Data were analyzed by χ2 statistical tests (P values) at a significance of 95%. The most effective removal of smear layer occurred with MCJ and NaOCl, both with a rinse of 17% EDTA. Both MCJ and NaOCl treatments were similarly effective with a rinse of 17% EDTA (P < .2471) to completely remove up to 80% of the smear layer from some aspects of the root canal. MCJ was more effective than CHX for removing smear layer (P < .0085) and saline as the negative control (P < .0001). The efficacy of MJC was similar to NaOCl in conjunction with EDTA as an intracanal irrigant. MJC appears to be the first fruit juice to be identified as a possible alternative to the use of NaOCl as an intracanal irrigant.
An Evaluation of Buccal Infiltrations and Inferior Alveolar Nerve Blocks in Pulpal Anesthesia for Mandibular First Molars
Il-Young Jung, DDS, MSc, PhD, Jun-Hyung Kim, DDS, Eui-Seong Kim, DDS, MSc, PhD, Chan-Young Lee, DDS, MSc, PhD, Seung Jong Lee, DDS, MSc, PhD
We compared the anesthetic efficacy of inferior alveolar nerve blocks (IANBs) with that of buccal infiltrations (BIs) in mandibular first molars. Using a crossover design, all subjects received a standard IANB or a BI of 1.7 mL of 4% articaine with 1:100,000 adrenaline (Septanest; Septodont, Saint-Maru-des-Fosses, France) on two appointments separated by at least 1 week. Pulpal anesthesia was determined by using an electric pulp tester. Electric pulp testing was repeated at 5, 8, 11, 15, 20, 25, and 30 minutes after the injections. Anesthesia was considered successful if the subject did not respond to the maximum output of the pulp tester at two or more consecutive time points. Fifty-four percent of the BI and 43% of the IANB were successful; the difference was not significant (p = 0.34). The onset of pulpal anesthesia was significantly faster with BI (p = 0.03). In conclusion, BI with 4% articaine for mandibular first molars can be a useful alternative for clinicians because compared with IANB it has a faster onset and a similar success rate.
Post Space Cleaning Using a New Nickel Titanium Endodontic Drill Combined with Different Cleaning Regimens
Ivanovic Coniglio, DDS, Elisa Magni, DDS, MSc, Cecilia Goracci, DDS, MSc, PhD, Ivana Radovic, DDS, MSc, Carlos Augusto Carvalho, DDS, Simone Grandini, DDS, MSc, PhD, Marco Ferrari, MD, DDS, PhD
This study compared the effect of two drills and five cleaning regimens on post space debridement. One hundred extracted premolars were instrumented and obturated with warm vertical compaction of gutta percha. The teeth were divided into two groups according to the drill used to remove gutta percha/sealer and for post space preparation: a Largo drill (Largo; Dentsply, St Quentin en Yvelines, France) or a MTwo-PF drill (Sweden&Martina, Due Carrare, Padova, Italy). The following cleaning regimens were used: EDTA, ultrasonics, ultrasonics + EDTA, phosphoric acid, and distilled water. Scanning electron microscopic images of the post spaces were taken, and the presence of debris and of open dentin tubules were evaluated. The ultrasonics + EDTA, phosphoric acid, and EDTA groups were comparable in open tubules scores for both drills and in debris scores after the use of MTwo-PF (p > 0.05). The ultrasonics and control groups performed significantly worse (p < 0.05). The MTwo-PF drill resulted as effective as the Largo drill in obtaining a good post space cleaning, especially when followed by ultrasonics + EDTA irrigant regimen.