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Mandibular Teeth (mandibular + tooth)
Selected AbstractsDetection of artificially induced vertical radicular fractures using Tuned Aperture Computed TomographyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2001Madhu K. Nair This study compared the accuracy of three imaging modalities for the detection of artificially induced vertical root fractures (VRF) on teeth in cadaver mandibles. Fifty-four single-rooted, endodontically treated mandibular teeth being prepared to carry posts were evaluated using direct digital radiography (DDI) with a Schick sensor, unprocessed Tuned Aperture Computed Tomography® (TACT-U) images and iteratively restored TACT (TACT-IR) images. Twenty-eight of these teeth had been subjected to fracture induction using an apically driven force. Nine basis images were used for each TACT image generation. Eight observers used a five-point confidence rating scale to record the confidence with which they considered a fracture to be present or not. Sensitivity and specificity values were computed and receiver operating characteristic (ROC) curves were generated. The areas under the curves (Az) used as an indication of the diagnostic accuracy of the imaging system were as follows: DDI: 0.37; TACT-U: 0.77 and TACT-IR: 0.81. DDI was significantly inferior to the TACT modalities. Differences in detection efficacy based on observers and observation sessions were noted on ANOVA and post-hoc Tukey's tests. This study indicates that TACT is the imaging modality of choice for VRF in endodontically treated teeth. [source] TOOTH WHITENING IN CHILDRENJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2005K.J. Donly ABSTRACT Objective: This clinical study evaluated the efficacy and tolerability of tooth whitening in children and adolescents, using a marketed, tray- based tooth-whitening system and a disposable polyethylene strip system. Materials and Methods: A study population of 106 children and adolescents, ages 11 to 18 years, participated in this study. There were 61 girls and 45 boys, with a mean age of 14.7 years. Subjects were divided into two experimental treatment groups, the groups being balanced with respect to demographic characteristics and baseline tooth color. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and the desire to whiten their teeth. One experimental group included 71 subjects who used a 6.5% hydrogen peroxide strip system (Crest Whitestrips Professional Strength, Procter & Gamble, Mason, OH, USA) for 30 minutes twice daily. The other experimental group included 35 subjects who used a 10% carbamide peroxide tray system (Opalescence, Ultradent Products, South Jordan, UT, USA) overnight. Subjects who had previously vital bleached their teeth, exhibited apparent caries or periodontal problems, had orthodontic appliances or anterior restorations, or reported dentin hypersensitivity were excluded. The study population was treated in two separate cohorts, by two independent investigations, to minimize the effects of examiner bias. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks, with the maxillary and mandibular arches being treated separately for 4-week intervals. An oral examination was conducted at baseline and at all recall intervals. Subjects reported any adverse events in interviews. Color change was calculated from digital images where L* indicated lightness, a* redness, and b* yellowness. Comparisons between the two experimental groups were made using a two-sided analysis of covariance with a 5% significance level. Results: Both experimental systems exhibited significant (p < .001) tooth-whitening improvement relative to the baseline. Color change was greater in the maxillary teeth than in the mandibular teeth for both systems evaluated. The color change for maxillary teeth was not significantly different between the two systems evaluated; however, the tray system demonstrated significantly (p < .05) greater toothwhitening effectiveness for the mandibular teeth. Both treatment regimens were well tolerated. Minor tooth sensitivity and oral irritation were the most commonly reported adverse events, being reported by 49% of the subjects assigned to the strip group and 43% of the subjects in the tray group. All reported that adverse events were relieved immediately upon discontinuance of product use. Conclusion: The 6.5% hydrogen peroxide gel strips and the 10% carbamide peroxide gel delivered overnight in customized trays effectively whitened teeth, and both treatment regimens were well tolerated. [source] Using a Motion-Capture System to Record Dynamic Articulation for Application in CAD/CAM SoftwareJOURNAL OF PROSTHODONTICS, Issue 8 2009Oliver Röhrle PhD Abstract Purpose: One of the current limitations of computer software programs for the virtual articulation of the opposing teeth is the static nature of the intercuspal position. Currently, software programs cannot identify eccentric occlusal contacts during masticatory cyclic movements of the mandible. Materials and Methods: Chewing trajectories with six degrees of freedom (DOF) were recorded and imposed on a computer model of one subject's maxillary and mandibular teeth. The computer model was generated from a set of high-resolution ,-CT images. To obtain natural chewing trajectories with six DOF, an optoelectronic motion-capturing system (VICON MX) was used. For this purpose, a special mandibular motion-tracking appliance was developed for this subject. Results: Mandibular movements while chewing elastic and plastic food samples were recorded and reproduced with the computer model. Examples of mandibular movements at intraoral points are presented for elastic and plastic food samples. The potential of such a kinematic computer model to analyze the dynamic nature of an occlusion was demonstrated by investigating the interaction of the second molars and the direction of the biting force during a chewing cycle. Conclusions: The article described a methodology that measured mandibular movements during mastication for one subject. This produced kinematic input to 3D computer modeling for the production of a virtual dynamic articulation that is suitable for incorporation into dental CAD/CAM software. [source] Herpes zoster in HIV infection with osteonecrosis of the jaw and tooth exfoliationORAL DISEASES, Issue 5 2006P Siwamogstham Background:, Herpes zoster (HZ) infection of the trigeminal nerve is associated with complications such as postherpetic neuralgia, facial scarring, loss of hearing ability and conjunctivitis. Until 2005, postherpetic alveolar necrosis and spontaneous tooth exfoliation have been described in 20 cases unrelated to HIV infection. Objective:, The aim of this study was to describe HIV infection in patients (two women, two men, average age 30 years) who suffered from HZ attacks to their trigeminal nerves. Main outcome measures:, None of the patients had received antiherpetic medications or antiretroviral therapy. HIV infection was only diagnosed after the development of HZ. Facial scarring with depigmentation and hyperesthesia (postherpetic neuralgia) was diagnosed in all four patients. Oral findings consisted of spontaneous loss of both maxillary or mandibular teeth. Osteonecrosis of varying extent was also found. Treatment consisted of extractions of teeth and administration of antibiotics and analgesics. Healing of alveolar wounds was unremarkable. Conclusion:, Complications affecting the alveolar bone and teeth seem to be rare in HIV-infected patients. [source] A rare case of dens invaginatus in a mandibular canineAUSTRALIAN ENDODONTIC JOURNAL, Issue 2 2010Roy George mds Abstract Dens invaginatus (dens in dente) is a common dental anomaly with a reported prevalence of between 0.04% and 10%. It typically affects permanent maxillary lateral incisors, central incisors and premolars. These developmental lesions are less common in mandibular teeth and are extremely rare in canines and molars. This report describes a rare case of dens invaginatus (Oehlers type II) in a permanent mandibular canine. The tooth was mature with a closed apex and showed apical pathosis. The tooth was treated endodontically using a non-surgical technique with hand endodontic files, and then followed up after a period of 8 months. A follow-up radiograph showed some healing of the lesion. [source] Teeth in a Day® for the Maxilla and Mandible: Case ReportCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2003Thomas J. Balshi DOS ABSTRACT Background: A growing body of evidence indicates that successful osseointegration of dental implants can take place in the wake of immediate loading, providing that bone quality and quantity are adequate, and patients follow postsurgical instructions carefully. Purpose: The goal of this report is to demonstrate the efficient treatment protocol based on immediate loading for both the maxilla and mandible, including extraction site locations. Materials and Methods: Following extraction of the remaining anterior mandibular teeth, 18 Brånemark implants (Nobel Biocare AB, Gothenburg, Sweden), including two zygoma and two pterygoid implants, were installed in both arches in accordance with the Teeth in a Day protocol developed by the authors 9 years ago. This protocol uses an acrylic screw-retained prosthesis, with steel prosthetic copings embedded, supported by full-size Brånemark implants to prevent micromotion at the bone-to-implant interface. Results: Only 1 of the 18 immediately loaded implants failed to osseointegrate. Three years after completion of treatment, the patient reported functioning well with no complications. Conclusions: When appropriate subjects are selected, the Teeth in a Day protocol offers patients a number of significant advantages, including condensed treatment time, reduced postsurgical discomfort, and almost instantaneous improvement in speech and masticatory function, esthetics, and patient self-image. [source] | ||||||||||