Effect of blood contamination on marginal adaptation of cold ceramic and MTA angelus: a scanning electron microscopic study.

BACKGROUND: This study aimed to assess the effect of blood contamination on marginal adaptation of cold ceramic (CC) and mineral trioxide aggregate (MTA) Angelus using scanning electron microscopy (SEM). METHODS: This in vitro experimental study was conducted on 24 extracted single-rooted human teeth. After cleaning and shaping, the root canals were filled with lateral compaction technique. The apical 3 mm of the roots was cut, and cavities with 3 mm depth were created at the apex. The teeth were randomly assigned to two group (n = 12) for the application of CC and MTA Angelus as retrograde filling materials. CC and MTA Angelus were prepared by mixing the powder with blood, and applied in the cavities. After 24 h, their marginal adaptation to the canal walls was assessed by SEM. Data were statistically analyzed by t-test (alpha = 0.05). RESULTS: The mean marginal gap was 8.98 µm in the CC, and 16.26 µm in the MTA Angelus group; this difference was statistically significant (P < 0.001). CONCLUSIONS: The present in vitro study revealed that following complete blood contamination of powder, CC showed significantly superior marginal adaptation than MTA Angelus as shown by SEM assessment.

Histological evaluation of ProRoot mineral trioxide aggregate and Cold ceramic as root-end filling materials in animal models.

Background: This study aimed to evaluate the reaction of the periapical tissue to Cold ceramic and mineral trioxide aggregate (MTA) following periapical endodontic surgery. Materials and Methods: In this experimental study, a total of 12 mandibular first, second, and third premolars of two male dogs were selected. All procedures were performed under general anesthesia. The access cavities were prepared, and the length of canals was determined. Root canal treatment was performed. A week later, periradicular surgery was performed. After osteotomy, 3 mm of the root end was cut. Then, a 3-mm cavity was created by an ultrasonic. The teeth were randomly divided into two groups (n = 12). The root-end cavities were filled with MTA in the first group and with Cold ceramic in the second group. After 4 months, the animals were scarified. Histological evaluation of the periapical tissues was performed. Data were analyzed using SPSS 22 and Chi-square test and P = 0.05. Results: The findings showed 87.5% and 58.3% cementum formation in MTA and Cold ceramic groups, respectively, indicating a significant difference (P < 0.001). In addition, the results showed 91.7% and 83.3% bone formation in MTA and Cold ceramic groups, respectively, but the difference was not statistically significant (P = 0.6). Furthermore, the findings revealed 87.5% and 58.3% periodontal ligament (PDL) formation in MTA and Cold ceramic groups, respectively (P = 0.05). Conclusion: Cold ceramic was able to induce the regeneration of cementum, bone, and PDL; hence, it can be considered as a biocompatible root-end filling material in endodontic surgery.

Nonsurgical Endodontic Management of Large Periapical Lesion with Cold Ceramic: A Literature Review and Case Series.

Introduction: The purpose of this review is to investigate the contribution of non-surgical endodontic treatment in the healing process of large periapical lesions as well as looking over other potential non-surgical endodontic treatment options. Materials and Methods: two females and one male patient were referred to the private office, complaining of having pain in the anterior maxillary region which was pertinent to the presence of a large periapical lesion, and subsequently were managed by a non-surgical endodontic approach using cold ceramic. The archive of PubMed and Google Scholar databases was also searched for finding relevant articles in which a nonsurgical endodontic approach was performed to improve the healing process of large periapical lesions. Results: Clinical examination of the case series subjects revealed no signs and symptoms following treatment while relative improvement of the lesion and apical closure was apparent in radiographs 7 months, 9 months, and 4 years subsequently. In twenty-two reviewed clinical trials, a total number of 107 teeth with large periapical lesions were treated by nonsurgical endodontic approaches using MTA, biodentine, gutta-percha, and bioceramic iRoot Bp plus. Complete healing occurred in 38 cases (35.5%) after 12-17 months. Conclusions: Although surgical interventions have been used previously in the management of large periapical lesions, a nonsurgical endodontic approach with cold ceramic seems to be effective, leading to complete healing of the periapical lesion in treated subjects. Further clinical research is recommended to identify the effectiveness of cold ceramic for the treatment of extensive periapical lesions.

Treatment of strip perforation using cold ceramic.

Root perforation may occur at any stage of endodontic treatment and is mostly due to iatrogenic injury and may compromise the outcome of endodontic treatment. Repairing a perforation is difficult and the prognosis depends on various factors such as time, site and size of perforation, and the patient's overall health status. Hence, choosing the most appropriate material can be critical for the dentist. In this case report of a strip-perforation repair, an mineral trioxide aggregate-like material (cold ceramic) that has been shown in previous studies to have favorable properties, was successfully used.

Successful management of a tooth with canal obstruction using "cold ceramic".

One of the causes of treatment failure is calcification in the canal pathway, which prevents complete access to proper working length, and one of the most difficult and challenging cases of root canal treatment has been reported. In some cases, the dentist will not be able to open the calcified canal. Therefore, the prognosis of root canal treatment in these cases has been reported poor, and the dentist will offer a plan for possible treatments, including tooth extraction or apical surgery. The presented case is one example of those cases with a periapical lesion, which as a temporary treatment, the pulp chamber was filled with cold ceramic. This material, which is an MTA-like (Mineral Trioxide Aggregate) bioceramic with proper sealing ability, has been introduced as a root-end filling material. After 6 years of which the patient returned, he did not express any pain or discomfort during these 6 years. Furthermore, in radiograph that was taken, periapical lesion relative healing and bone regeneration were amazingly seen.

Evaluation of the response to electric pulp testing in multiple sclerosis patients without a history of trigeminal neuralgia: a case-control study.

BACKGROUND: The importance of evaluating the pulpal threshold to electrical stimulation, as a side effect of probable neuropathy in Multiple Sclerosis (MS) patients is a novel issue. This study aimed to investigate electrical pulp test thresholds in MS patients without a history of trigeminal neuralgia compared to healthy individuals. METHODS: Sixty-nine maxillary central incisors, belonging to 34 relapsing-remitting MS patients, and 35 healthy individuals were included in this survey. The MS patients matched for intended variables, were 22-50 years old, had a more than 1-year history of MS, no history of trigeminal neuralgia and/or other neuropathy. The electric pulp sensibility test was performed on all samples. Electric pulp testing (EPT) results were recorded based on the pulp tester's grade that evoked a response. Data were analyzed with paired T-test, Mann-Whitney test, and Spearman correlation (P < 0.05). RESULTS: According to the results of this study, the mean values of response to EPT were 1.2 ± 0.5 and 1.8 ± 0.5 in MS patients and healthy individuals, respectively. The pulpal response to EPT between the two groups was significantly different (P < 0.0001). CONCLUSIONS: MS patients showed a significantly reduced response to the electric pulp test in their maxillary central incisors in comparison to matched healthy persons.

The cold ceramic material.

The purpose of this paper was to review the composition, sealing ability, biocompatibility and various physical properties of cold ceramic (CC) material that potentially used as a root filling material. The review of the articles was performed by electronic and manual searching methods regarding the properties of CC from November 2000 to May 2016. The results revealed that there were many published reports carried out on the properties of CC. Only one article had extensively studied the composition of CC, five studies had investigated the sealing ability of CC, three articles had studied the biocompatibility, and some studies had investigated the radiopacity, setting time, pH value, and solubility of CC. It was concluded that CC material had good potential for endodontic use. Furthermore, clinical studies are needed in these areas.

Irreversible pulpitis and achieving profound anesthesia: Complexities and managements.

Dental pain management is one of the most critical aspects of modern dentistry. Irreversible pulpitis and further root canal therapy might cause an untolerated pain to the patients. The improvements in anesthetic agents and techniques were one of the advantages of studying nerve biology and stimulation. This article tried to overview of the nerve activities in inflammatory environments or induced pain. Furthermore, the proper advises, and supplementary techniques were reviewed for better pain management of irreversible pulpitis.

Accuracy of an Electronic Apex Locator for Working Length Determination in Primary Anterior Teeth.

OBJECTIVES: Correct determination of working length is an important step for success of endodontic therapy. Conventional radiography has limitations in providing the accurate location of apical foramen. For this reason, electronic apex locators (EALs) were developed to shorten the treatment time and decrease the radiation dose. The aim of this study was to evaluate the accuracy of Root ZX EAL for working length determination in primary anterior teeth. MATERIALS AND METHODS: In this in-vitro study, 50 extracted primary anterior teeth with root resorption were selected with no obstructed canals or history of previous root canal therapy. Working lengths were measured by direct observation of actual length (AL), radiography and Root ZX EAL. A variation of ±0.5 mm from the AL was considered acceptable. The results were analyzed statistically using paired t-test and interclass correlation coefficient (ICC) at 0.05 level of significance. RESULTS: Considering an acceptable 0.5 mm margin from AL (direct measurement), the accuracy of Root ZX EAL and radiography was found to be 86% and 76%, respectively. Absolute value of error from AL was significantly lower for ZX compared to radiography (P<0.001). Interclass correlation comparing both radiography and Root ZX with AL showed strong correlations. CONCLUSION: Root ZX EAL can be used as a reliable tool for obtaining root canal length in primary anterior teeth with resorption.

The Effect of Orthodontic Forces on Tooth Response to Electric Pulp Test.

INTRODUCTION: The current study investigated the pulp response to electric pulp testing (EPT), before, upon initiation and one month after the start of orthodontic tooth movement. METHODS AND MATERIALS: A total of 402 anterior teeth from 39 patients (mean age of 16.8±2.7 years) were examined in this non-controlled prospective study. The aligning forces were administered using initial NiTi archwires ligated on fixed appliances by using the MBT straight wire technique. The electrical stimulation was provided by the EPT. The EPT readings were recorded at three time points: before bonding (EPT0), immediately upon initiation (EPT1) and 1 month post-treatment (EPT2). The data were statistically analyzed by the ANOVA and Bonferroni tests (P<0.05). RESULTS: Prior to bonding of the orthodontic brackets, the mean EPT value for all the experimental teeth was 3.42 EPT units. Upon initiation, the mean value of EPT1 for each tooth increased to 7.62 units. One month later, the mean EPT2 values dropped to 6.27 units. At this time point, 64 teeth (16%) of the experimental teeth failed to respond. The differences among EPT values at different time points were significant. There was no association between the EPT values and the location or the type of teeth. CONCLUSION: The physiological changes in the pulp affect the nerve fibers in the early stages of the orthodontic force application. As a result, thresholds to electrical stimulation would increase and the EPT may not initiate a response. Therefore results obtained by electrical pulp testing should be interpreted accordingly.

Comparing the Marginal Adaptation of Cold Ceramic and Mineral Trioxide Aggregate by Means of Scanning Electron Microscope: An In vitro Study.

BACKGROUND: Long-term success of endodontic surgeries is often influenced by the type of root-end filling material (RFM). The aim of present study was to compare the marginal adaptation of two different RFM, cold ceramic (CC) and mineral trioxide aggregate (MTA), using scanning electron microscope (SEM). MATERIALS AND METHODS: About 20 extracted human single-rooted teeth were collected and stored into sodium hypochlorite 5.25%. The teeth were decronated from the cemento-enamel junction to prepare 16 mm roots. The working length was measured, and 1/3 coronal of the canal was prepared by Gates-Glidden drills. Apical flaring was followed by K file size # 40-70 based on step back technique. After filling of the canals, 3 mm above the apex was cut at 90° to the long axis. Furthermore, 3 mm of the filling was removed from the apical part using the ultrasonic device. All of the prepared specimens were divided into two groups and were retro filled by MTA and CC. The roots were cut horizontally from 1 mm above the apical part, and dentin-filling material interface was observed by SEM. Finally, the collected data were analyzed by Mann-Whitney test and using SPSS software version 18 at a significant level of 0.05. RESULTS: The mean interfacial adaptation was higher in CC group. However, no significant differences were observed by statistical test (P = 0.35). CONCLUSION: Both CC and MTA had similar marginal adaptation as RFM however in vivo studies are recommended for better determination.

The effect of budesonide on orthodontic induced root resorption.

BACKGROUND: The aim of this study was to evaluate the hypothesis that budesonide increases the susceptibility of teeth to root resorption during the course of orthodontic treatment. MATERIALS AND METHODS: A randomized controlled trial design (animal study) was employed. Budesonide was administered in test group for 14 days during which orthodontic force was applied to upper right molar. Afterwards, root resorption was measured on mesio-cervical and disto-apical parts of the mesial root on transverse histological sections. ANOVA and Bonfferoni tests were used. Statistical significance was considered to be P ≤ 0.05. RESULTS: In general, the subgroups in which the force was applied showed significantly greater root resorption. Where force was applied there was no significant difference, whether budesonide was administered or not. While where there was no force, a group who received budesonide showed significantly greater root resorption than the other, unless at the coronal level where the difference was not significant. CONCLUSION: Within the limitations of this study, it seems budesonide could increase root resorption, but in the presence of orthodontic force this effect is negligible.

Lack of correlation between microbial penetration method and electro chemical technique for assessment of leakage through the root canal fillings.

AIMS: The purpose of this study was to compare microbial penetration method and electrochemical technique for evaluation of the apical seal. MATERIALS AND METHODS: A total of 28 teeth were prepared using the step-back technique to ISO size 40 master apical files. The specimens were randomly divided into an experimental group, two positive and two negative controls. Root canals in the experimental and negative control group were filled with gutta-percha (GP) and sealer, using lateral condensation technique. In the positive control group, canals were filled with GP without any sealer. The external surface of each tooth was coated with two layers of the nail varnish, except for the access opening and the apical foramen. In the negative control group, the teeth were completely covered with nail varnish. The apical seal was recorded with two methods, each successively used on the same teeth: An electrochemical method and a bacterial penetration method. STATISTICAL ANALYSIS USED: The correlation of the electro chemical readings with the results obtained from bacterial micro leakage test was evaluated by Pearson's correlation coefficient. RESULTS: Correlation coefficient of the measurements obtained from the two evaluation methods, was 0.23 (r = 0.23), so the correlation was not statistically significant (P = 0.275). CONCLUSIONS: This study shows that several studies by different methods are necessary before evaluation of the marginal leakage.

The effect of ovalbumin on orthodontic induced root resorption.

BACKGROUND: This randomized trial was undertaken to investigate the effect of experimentally induced allergy on orthodontic induced root resorption. MATERIALS AND METHODS: A total of 30 Wistar rats were divided randomly into test and control groups. Starting from the first 3 days, the rats in the test group were injected intra-peritoneally by 2 mg ovalbumin as allergen and 0.5 mg Alume as adjuvant. Afterward only allergen was injected once a week. The control group was injected by normal saline. After 21 days, Wistar immunoglobulin E was measured and peripheral matured eosinophil was counted. A total of 50 g nickel-titanium closed coil spring was ligated between right incisor and first molar. All animals were sacrificed after 14 days. The mesial root of the right and left first molar was dissected in a horizontal plane. The specimens were divided into four groups considering whether force and/or ovalbumin was applied or not. Root resorption was measured and compared among these groups. Repeated measures analysis of variance (ANOVA), and Bonferoni tests were used to analyze the data. The level of significance was determined at 0.05. RESULTS: In general, the differences were insignificant (P < 0.05). As the only exception, the group in which both ovalbumin and force were applied had significantly more root resorption than the group in which neither force nor ovalbumin was applied (P > 0.001). CONCLUSION: Allergy may increase the susceptibility to root resorption. Application of light force, periodical monitoring of root resorption and control of allergy are advisable.

Comparing the sealing properties of mineral trioxide aggregate and an experimental ceramic based root end filling material in different environments.

BACKGROUND: An apical seal is an important factor in achieving success in surgical endodontics. AIM: The purpose of this study was to compare the sealing properties of mineral trioxide aggregate (MTA) with a new ceramic based root end filling material (Cold Ceramic) in different environments. MATERIALS AND METHODS: One hundred teeth were selected. The root canals were instrumented and obturated. Except for the apical 2 mm, the root surfaces were sealed. After root resection, 3 mm depth root-end cavities were prepared. For each material, roots were divided into 3 equal subgroups and the root-end filling was done in different environments (dry, saliva contaminated, blood contaminated). Five roots served as positive and 5 roots as negative controls. Samples were immersed in 2% methylene blue dye. Roots were sectioned longitudinally and examined under stereomicroscope to record the extension of dye penetration. RESULTS: All experimental groups demonstrated dye penetration. The lowest linear leakage was seen in Cold Ceramic blood contaminated group while the highest leakage was observed in MTA blood contaminated group. The linear dye penetration of both MTA and Cold Ceramic (CC) groups did not show any significant differences among different environments. Also, the difference between MTA and CC was not significant in dry and saliva contaminated subgroups. Only the difference between dye penetration of MTA and CC in blood contaminated subgroups showed significant difference ( P = 0.008). CONCLUSION: The sealing property of this ceramic based root end filling material (Cold Ceramic) is better than MTA in blood contaminated condition and at least similar to MTA in other conditions.

Undetected microscopic pulp exposures in deep class II cavities.

Exposure of the pulp may act as a great insult during preparations, so this study investigated the probability of clinically undiagnosed pulp microexposures. The axial wall of 30 deep class II preparations in human premolars was searched for any microexposure after extraction. Seven teeth (23.7 percent) showed some kind of exposure. It is concluded that approximately one-fifth of class II preparations with the remaining dental thickness (RDT) less than 0.5 mm may have a pulpal microexposure.

Undetected microscopic pulp exposures in deep class II cavities.

Exposure of the pulp may act as a great insult during preparations, so this study investigated the probability of clinically undiagnosed pulp microexposures. The axial wall of 30 deep class II preparations in human premolars were searched for any microexposure after extraction. Seven teeth (23.7 percent) showed some kind of exposure. It is concluded that approximately 1/5 of class II preparations with the RDT less than 0.5mm may have a pulpal microexposure.

Effect of pulp inflammation on nerve impulse quality with or without anesthesia.

Absence of complete anesthesia in teeth with acutely inflamed pulp is a well-known clinical symptom, but the mechanism behind this symptom is poorly understood. In the current electrophysiologic study, afferent nerve fiber responses of the inflamed tooth with and without anesthesia were compared with normal teeth. Seventeen cats were used in this experimental study. After inducing inflammation in one canine tooth, the responses of afferent nerves from the inflamed and control contralateral canine tooth neurons were compared before and after application of anesthesia. In most cases, 2 distinct responses in both normal and inflamed sites were recorded. The conduction velocity was significantly lower in the nerve to the inflamed side compared with the control side. In contrast, the response intensity was significantly higher in the inflamed side compared with the control side. It was also found that it was markedly more difficult to inhibit impulse transmission by using anesthesia on the inflamed side, whereas there was no trouble inhibiting impulses on the control side.

Sealing ability of a new experimental "cold ceramic" material compared to glass ionomer.

OBJECTIVE: The purpose of this study was to compare the sealing ability of a new experimental material named "cold ceramic" with glass ionomer using an electrochemical method. METHODOLOGY: Forty extracted human teeth were used in this study. The crowns were removed at the cemento-enamel junction. The roots were prepared, the apical 3 to 4 mm of each root was resected, and a class 1 cavity of 2 mm depth was prepared. After application of nail polish to the external surface of the roots, the samples were randomly divided into two groups, each with 20 roots. Each sample was filled with one of the two materials. After 24 hours, to allow complete setting, the roots were immersed in normal saline solution for 10 days. Microleakage was measured by an electrochemical method. RESULTS: The results indicated that there is a statistically significant difference in the microleakage between the two materials (p = 0.0001), with the cold ceramic providing a better seal than the glass ionomer. CONCLUSION: Cold ceramic has proper sealing ability and reduced initial setting time that demonstrate its potential as a root end filling material.

The efficacy comparison of ibuprofen, acetaminophen-codeine, and placebo premedication therapy on the depth of anesthesia during treatment of inflamed teeth.

The purpose of this study was to elucidate whether premedication therapy with acetaminophen-codeine or ibuprofen is able to increase the depth of anesthesia in inflamed teeth. Sixty patients with the diagnosis of irreversible pulpitis in 1 mandibular tooth requiring root canal therapy (RCT) were selected. Two other teeth in the same quadrant were selected as controls. An electric pulp tester (EPT) was used to evaluate pulp sensitivity at the baseline and after drug administration and anesthesia injection. The subjects were divided into 3 groups randomly, and in each group 1 of the 3 drugs including acetaminophen-codeine, ibuprofen, and placebo were administered 1 hour before anesthesia delivery. After 1 hour, anesthesia was injected and after a waiting period, the EPT measurement was recorded. The reversed EPT scale was used to evaluate the depth of anesthesia achieved during RCT. Data were analyzed to statistically compare the results before and after intervention in cases and controls of each group and among different groups. Significanly lower tooth sensitivity levels (TSLs) were observed after intervention in acetaminophen-codeine and ibuprofen groups, which was more significant in the ibuprofen group. The comparison of inflamed teeth TSLs in the acetaminophen-codeine group and the placebo group after anesthesia and drug administration showed significant differences (P = .001). This comparison between ibuprofen and placebo groups also showed significant differences (P approximately 0). Also, significantly lower TSL of inflamed teeth was observed in the ibuprofen group in comparison with the acetaminophen-codeine group (P = .002). This study reflected preoperative administration of ibuprofen, if not contraindicated, as a drug of choice 1 hour before local anesthesia injection as an effective method for achieving a deep anesthesia during RCT of teeth with irreversible pulpitis.