Browsing by Subject "Tooth"

Now showing 1 - 5 of 5
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    Heat testing methodology comparison.
    (2010-08) Bierma, Mark M.
    Pre-operative pulpal and periapical diagnosis is critical for effective and appropriate endodontic treatment. Occasionally patients present with a chief complaint involving hypersensitivity to heat – a hallmark sign of irreversible pulpitis. In an attempt to replicate this chief complaint, a variety of clinical methods have been developed to deliver a heat stimulus to a tooth. Friction from a burlew wheel, heated gutta-percha, a heated instrument, and hot water have all been used to warm teeth. Recently, an instrument has been developed which is heated electronically and placed directly against a tooth. The aim of this study was to determine which of these methods produces the most consistent temperature rise within the pulp of a tooth. The value of this consistency is that it allows clinical differentiation between a normal pulp and a pulp demonstrating irreversible pulpitis. The present study used extracted maxillary teeth with thermocouples mounted within the pulp chamber. Four operators applied the following methods to the teeth: heated gutta-percha, heated ball burnisher, hot water, and an electronic probe attached first to a System B™ and then to an Elements™ unit. Each test was performed for 60 seconds, and the temperature recorded every half-second. Analysis of the data revealed the most consistent warming of the pulp was accomplished with the electronic probe attached to the Elements™ unit. The lowest level of consistency was found with hot water. The electronic probe also yielded temperature changes which were more consistent between operators compared to the other three methods.
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    Mri Detection Of Vertical Root Fractures In Endodontically Treated Teeth
    (2020-08) Groenke, Beth
    INTRODUCTION: Vertical root fracture (VRF) is known to occur in root canal treated (RCT) teeth and results in tooth loss. VRFs are difficult to diagnose. Magnetic Resonance Imaging (MRI) has the potential to identify VRF due to beneficial partial volume averaging, without using ionizing radiation. This investigation aims to compare the sensitivity and specificity of MRI versus cone-beam computed tomography (CBCT) in detecting VRF, using micro-computed tomography (microCT) as the reference standard. It also will describe the limits of MRI for detecting VRF. METHODS: 115 extracted human tooth roots were RCT using common techniques. VRFs were induced in a proportion that resulted in 62 VRF samples and 53 non-fractured control samples. All samples were imaged in a phantom using MRI and CBCT. Axial images for MRI and CBCT were presented to three board-certified endodontists. Evaluators determined VRF status and a confidence assessment for that decision. 30% of images were resampled to calculate intra- and inter-rater reliability. For MRI, the most coronal slice with discernible VRF was measured on correlated microCT to determine the minimum VRF width (µm). RESULTS: Sensitivity for MRI and CBCT were 0.66 (95%CI:0.53-0.78) and 0.58 (95%CI:0.45-0.70). Specificity was 0.72 (95%CI:0.58-0.83) and 0.87 (95%CI:0.75-0.95). Intra-rater reliability ranged from k=0.29-0.48 for MRI and k=0.30-0.44 for CBCT. Inter-rater reliability for MRI was k=0.37 and CBCT k=0.49. Median VRF width detected using MRI was 39µm (first quartile:20µm, third quartile: 58µm). CONCLUSION: MRI demonstrated ability to repeatedly detect VRF as small as 20 µm. There was no significant difference between sensitivity nor specificity for MRI versus CBCT in detecting VRF, despite the early stage of MRI development.
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    The Relationship Between the Amount of Orthodontic Tooth Movement and the Effectiveness of Computer Assisted Treatment
    (2017-06) Czarnik, Scott
    Aim: To evaluate the effectiveness of SureSmile technology and determine if a correlation exists between discrepancy and overall movement throughout treatment. Methods: Digital pre-treatment models, predicted final treatment models, and actual final treatment models of 30 patients were superimposed to determine both the overall movement each tooth completed throughout treatment, the amount of discrepancy between predicted and actual results, and if any correlation exists between these two findings. Results: Statistically significant correlation between amount of overall tooth movement and discrepancy between predicted and actual final alignment was found in the following instances: Mesial-distal dimension in maxillary canines. Facial-lingual dimension of maxillary central incisors, and lateral incisors. Torque of maxillary central incisors, lateral incisors, 1st molars, and all mandibular teeth. Rotation of maxillary central incisors. Conclusion: The effectiveness of SureSmile is highly variable and dependent on tooth type and dimension of movement.
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    The Systemic Effect of local Injection of clodronate on orthodontic tooth movement in rats
    (2013-06) Issa, Omar Mohamed
    Clodronate is a non N-containing bisphosphonate that inhibits osteoclast maturation and function. The aim of the study was to assess the systemic effect of local administration of Clodronate on orthodontic tooth movement on rats. Two groups of Sparague-Dawley rats were used. Rats in the experimental group were injected with 50 µl of Clodronate solution on the same side every 3 days for 3 weeks and those in the control group received 50 µl saline solution at the same schedule. Two NiTi-coil springs exerting a constant 50 gm-force, were activated across the span from the central incisors to the first right and left maxillary molars. As the first molar tipped mesially, a diastema between the first and second molars was created. A histomorphometric analysis was used to calculate the mineral apposition rate (MAR) and the diastema between the maxillary first and second molars. The results indicate that (i) average diastema was less in Clodronate injection side group (ii) MAR was less in Clodronate injection side (iii) neither the appliance placement nor the injection inhibited the rat's ability to gain weight. Further study is necessary to determine the reproducibility of these effects.
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    Will Topical Application of Alendronate Disodium to Dental Roots Reduce Osteoclast Adherence and Resorption in Vitro?
    (2016-08) Finley, Rhett
    Introduction: The purposes of this study were: 1. To demonstrate the presence of fully differentiated, multinucleated human osteoclasts on bovine and human dentin and cementum in vitro. 2. To comparatively quantify osteoclast presence and distribution on tooth sections and adjacent lab wells following differentiation. 3. To comparatively quantify the amount of resorption that occurs when human root sections are subjected to a bisphosphonate antiresorptive treatment in comparison to no treatment. Materials and Methods: 30 sections of human tooth root and 48 sections of bovine tooth root were created using an IsoMet saw. The tooth sections from both groups were then divided into 2 equal groups of 15 and 24 sections respectively. One group received no treatment and the second group was soaked in 2mM Alendronate Disodium prior to transfer to culture. All sections were then plated in sterile culture wells with osteoclast precursor cells derived from whole human blood. The sections remained in culture until completion of osteoclastic differentiation, which took approximately 24 days. The supernatant was recovered from each well and used in an ELISA to determine the CTX-1 breakdown products from each section. The sections were fixed in paraformaldehyde and TRAP stained for visualization of osteoclasts. TRAP+ cell counts were performed on tooth sections and residual treatment wells. Student t-tests were used to determine differences between groups Results: Osteoclast attachment was observed on all human and bovine samples with the exception of one bacterially contaminated sample. The no treatment group had significantly more TRAP+ cells than the ALN group on both the human and bovine tooth sections. The no treatment group also had significantly more cells per residual well than the ALN group. No evidence of osteoclastic resorption could be demonstrated with the ELISA. Conclusions: Within the limitations of this study, it can be concluded that: 1. Fully differentiated, multinucleated osteoclasts can be successfully isolated from whole human blood and seeded onto human tooth sections in vitro. 2. Topical application of ALN disodium to extracted and sectioned tooth surfaces suppresses osteoclastic proliferation and differentiation in vitro. 3. Bovine teeth and human teeth allow for similar human osteoclast attachment and distribution in an in vitro model. 4. Mononuclear osteoclasts do not exhibit appreciable resorptive potential on sectioned surfaces in vitro.