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Sample records for tooth extraction

  1. Necessity of analgesics prescription after tooth extraction

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    Tozoglu Sinan

    2009-01-01

    Full Text Available Introduction. For patients and surgeons, pain and discomfort associated with dento-alveolar surgery can be a frightening prospect. This study was aimed to check whether prescription of analgesics is necessary or not after simple extraction of the mandibular third molars. Material and methods. Seventy-six dental outpatients undergoing uncomplicated extraction of both mandibular third molars teeth served as subjects. After extraction on the first side, patients received either naproxen sodium 550 mg orally or a placebo. The order of the drugs was reversed during extraction on side two. The postoperative pain was scored with a six-point category rating scala. The obtained data were analyzed with Mann-Whitney U-test. Results. The sum of the pain intensity for hours 2 through 8 was less for the group that received sodium naproxen. For hours 8-24, the sum of the pain intensity was less for the placebo group but this difference was not statistically different. Conclusion. This study shows that uncomplicated tooth extraction did not cause a significant postoperative pain and there was no need to prescribe analgesics for such cases.

  2. Endoscopic Extraction of the Impacted Wisdom Tooth from Maxillary Sinus

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    Larin R.A.

    2013-03-01

    Full Text Available We described a case of laterally situated impacted wisdom tooth extraction in maxillary sinus using an endoscopic endonasal approach. The technique was shown to be an adequate alternative to a traumatic transmaxillary approach earlier applied in such cases.

  3. Immediate bone augmentation after infected tooth extraction using titanium membranes.

    Science.gov (United States)

    Kfir, Efraim; Kfir, Vered; Kaluski, Edo

    2007-01-01

    Infectious process frequently results in extensive bone resorption and defect, periradicular or periapical lesions, or vertical fracture with infected sinus tract. When tooth extraction is mandated it typically results in additional bone loss in the buccal or lingual cortical plate. Immediate guided bone regeneration (GBR) and implant fixation at an infected site is frequently complicated by soft-tissue dehiscence, membrane exposure, and implant failure. The objective of this research is to assess the feasibility of immediate bone augmentation (IBA) after purulent tooth extraction, employing a dedicated titanium membrane. An intrasulcular incision was made around the tooth to be extracted and extended to 2 adjacent teeth while maintaining the papillae. Vertical releasing incisions were made to mobilize the mucoperiosteal flap. Cautious tooth extraction was executed utilizing conventional measures and was followed by meticulous curettage of the infected and granulated tissue in the socket. Titanium membranes were applied to the socket walls followed by socket filling with autologous platelet-rich fibrin and primary closure. Eight or more weeks later membrane removal and implant placement were performed. Of the 15 patients who underwent this procedure, 7 patients (47%) had early membrane exposure (between weeks 2 and 6), which was treated conservatively. No infection or early membrane removal was reported. All patients achieved sufficient bone augmentation, and 8 patients received implants without any additional GBR. IBA after infected tooth extraction, using titanium membrane application was feasible and safe and yielded adequate bone filling to support implant fixation at > or =8 weeks. Further studies need to evaluate if the titanium membrane helped in any way to inhibit plaque accumulation or resist infection in cases of early membrane exposure. PMID:17674679

  4. Necessity of analgesics prescription after tooth extraction

    OpenAIRE

    Tozoglu Sinan; Gungormus Metin; Buyukkurt Cemil M.; Yavuz Selim M.

    2009-01-01

    Introduction. For patients and surgeons, pain and discomfort associated with dento-alveolar surgery can be a frightening prospect. This study was aimed to check whether prescription of analgesics is necessary or not after simple extraction of the mandibular third molars. Material and methods. Seventy-six dental outpatients undergoing uncomplicated extraction of both mandibular third molars teeth served as subjects. After extraction on the first side, patients received either naproxen sodium 5...

  5. Subcutaneous emphysema as a complication of tooth extraction

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    Vaci? Aca

    2004-01-01

    Full Text Available Subcutaneous emphysema is a rare complication in dentistry, which may lead to diagnostic errors and inadequate therapy. A 17 years old female patient, in whom the separation of tooth roots was performed by the use of air-powered drill during the extraction of the first right lower molar, is presented in this paper. During the intervention, swelling of the right half of the face and the lower eyelid suddenly occurred, accompanied with simultaneous feeling of choking, and pressure in the neck and chest. Because of the suspicion of the allergic reaction, the patient was administered antihistaminic agent, together with parenteral corticosteroid, and was sent to an institution where she was treated as an in-patient. During hospitalization, subcutaneous emphysema of the face and neck was diagnosed by physical and x-ray examination. The emphysema completely disappeared after the use of oxygen and antibiotics.

  6. A Case of Recurrent Neuro-Behçet's Disease after Tooth Extraction

    OpenAIRE

    Choi, Seong-Min; Choi, Yun-Ju; Kim, Joon-Tae; Lee, Seung-Han; Park, Man-Seok; Kim, Byeong-Chae; Kim, Myeong-Kyu; Cho, Ki-hyun

    2009-01-01

    We report a 39-yr-old man with neuro-Behçet's disease (NBD) in remission who developed left-sided ataxia with a sensory deficit about 10 days after tooth extraction. Several years ago, he experienced a similar episode of relapse after tooth extraction. Brain magnetic resonance imaging showed a newly developed right thalamic lesion. In cerebrospinal fluid, lymphocyte-dominant pleocytosis and mild elevation of IgG were found. Immunologic factors may be important in the pathogenesis of NBD becau...

  7. The role of traditional healers in tooth extractions in Lekie Division, Cameroon

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    Naidoo Sudeshni

    2011-05-01

    Full Text Available Abstract Background The extraction of the teeth by traditional healers in Cameroon is an established cultural practice in the central region of the Cameroon. Traditional healers (TH use herbs and crude un-sterilized instruments and tools for the tooth extraction procedure. The present study investigates the knowledge and practices of traditional healers regarding tooth extraction and the management of its complications. Methods A cross sectional design utilizing semi-structured questionnaires was used to collect the data from traditional healers and their patients. Results Sixteen traditional healers (TH were interviewed. All were male and the majority were between 25-35 years old. The most important reason given for the removal of a tooth was "if it has a hole". All reported using herbs to control bleeding and pain after extractions. Only 20% used gloves between patients when extracting a tooth and just over a third (31.3% gave post-operative instructions. Eighty seven percent managed complications with herbs and 62.5% reported that they would refer their patients to a dentist whenever there are complications. Only a third (31.3% was familiar with the basic anatomy of a tooth and more than half (56.3% reported that tooth extractions are the only treatment for dental problems. One hundred and fifty patients were interviewed with a mean age of 29 years. More than two thirds were in the 21-30 year age group and just over half were male. Sixty six percent reported that they visited the TH because it is cheap, 93.3% were satisfied with the treatment they received while 95.3% reported said they never had a problem after an extraction. Conclusions Tooth extractions using medicinal plants is well established in Lekie division, Cameroon. Infection control during extraction is not the norm. Traditional healers are willing to co-operate with oral health workers in improving the oral health of their patients. Mutual cooperation, collaboration and integrating TH into primary oral health care services need to be increased.

  8. Fate of the buccal bone at implants placed early, delayed, or late after tooth extraction analyzed by cone beam CT

    DEFF Research Database (Denmark)

    Schropp, Lars; Wenzel, Ann; Spin-Neto, Rubens; Stavropoulos, Andreas

    2015-01-01

    AIM: To present 10-year cone beam CT (CBCT) data on the fate of buccal bone at single-tooth implants placed early, delayed, or late after tooth extraction. MATERIAL AND METHODS: Sixty-three of 72 patients, originally randomly allocated to three equal-size groups, received a single-tooth implant on average 10 days (Ea; N = 22), 3 months (De; N = 22), or 1.5 years (La; N = 19) after tooth extraction. Healing abutments were mounted after a 3-month period of submerged healing and metalceramic crowns...

  9. Effect of irradiation on wound healing after tooth extraction in the rachitic rats

    International Nuclear Information System (INIS)

    To observe the histopathological changes following irradiation on the wound healing after tooth extraction in the rachitic rats. In order to carry out this study, the rats were divided into four groups: Group 1 (normal diet/non-irradiation group), Group 2 (normal diet/irradiation group), Group 3 (rachitogenic diet/non-irradiation group), and Group 4 (rachitogenic diet/irradiation group). Rachitic changes were induced with rachitogenic diet No. 2 (high calcium, low phosphorus, and Vitamin D deficient diet) for 5 weeks. After the extraction of both maxillary first molars of the rats in Group 2 and 4, the head and neck of the rats were irradiated with single absorbed dose of 10 Gy. The rats were sacrificed at the 1st, 5th, 10th, and 15th day after tooth extraction. The specimens including the extraction wound were sectioned, stained with the hematoxylin-eosin and Masson's trichrome method and examined under the light microscope. In the Group 2, the amount of newly formed bone trabeculae on the periphery of extraction socket and osteoblastic activity were reduced. In the Group 3, epithelial fusion was not revealed on the 5th day after toothe extraction and growth rate of osteoid formation was reduced. In the Group 4, necrotized tissue at the outer surface of extraction socket and destructive changes on the alveolar bones were noted on the 10th day. Epithelial fusion was not revealed and large amounts of osteoclast were noted on alveolar bone on the 15th day. The healing process of wound after tooth extraction was retarded by irradiation and especially in the rachitic rats.

  10. Preventing wrong tooth extraction: experience in development and implementation of an outpatient safety checklist.

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    Saksena, A; Pemberton, M N; Shaw, A; Dickson, S; Ashley, M P

    2014-10-01

    Extraction of the wrong tooth or teeth is a serious and avoidable clinical error causing harm to the patient. All NHS Trusts in England are required to use a surgical safety checklist in operating theatres to prevent incorrect site surgery and ensure safe management of patients. However, the majority of patients have dental extractions and other oral surgical procedures undertaken on an outpatient basis and these patients are also at risk of having an incorrect site surgical procedure such as a wrong tooth extraction. We describe our experience in developing, introducing and refining a surgical safety checklist for outpatient oral surgery along with the key strategic actions needed to ensure effective cultural change and optimum patient safety in the outpatient setting. PMID:25303583

  11. Histometric study of socket healing after tooth extraction in rats treated with diclofenac

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    Yugoshi Luciana Ibara

    2002-01-01

    Full Text Available The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.

  12. Evaluation of Amoxicillin & Cephalexin concentrations in dental alveolar sockets after tooth extraction

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    Fakhraei AH.

    2005-06-01

    Full Text Available Statement of Problem: One of the most important complications after tooth extraction and oral and maxillofacial surgery is transient bacteraemia and prescription of prophylactic antibiotic is necessary to prevent postoperative infections in immunocompromised patients. Purpose: The aim of this study was the evaluation of cephalexin and amoxicillin concentrations in dental alveolar sockets following tooth extraction. Materials and Methods: In this interventional study, 80 healthy patients subjected to tooth extraction were divided into two groups. Each group received 1 gr amoxicillin or cephalexin and teeth were extracted 30-60-90-120-180 minutes after antibiotic intake. Blood sampling was performed immediately after extraction and concentrations of two antibiotics were measured in microbiology laboratory. ANOVA test and Post-hoc (Duncan test were used for statistical analysis with P<0.05 as the limit of significance. Results: The maximum serum concentration was 10.1006 ?g/ml for amoxicillin at 120 minutes and 41.5467 ?g/ml for cephalexin at 90 minutes after drug intake. The minimum inhibitory concentration (MIC of cephalexin and amoxicillin for Streptococcus sanguis was 2 ?g/ml and 1 ?g/ml respectively. Conclusion: The mean concentration for amoxicillin was 10 times and for cephalexin was 20 times higher than MIC.

  13. Effects of local and whole body irradiation on appearance of osteoclasts during wound healing of tooth extraction sockets in rats

    International Nuclear Information System (INIS)

    We examined effects of local and whole body irradiation before tooth extraction on appearance and differentiation of osteoclasts in the alveolar bone of rat maxillary first molars. Wistar rats weighting 100 g were divided into three groups: non-irradiation group, local irradiation group, and whole body irradiation group. In the local irradiation group, a field made with lead blocks was placed over the maxillary left first molar tooth. In the whole body irradiation group, the animals were irradiated in cages. Both groups were irradiated at 8 Gy. The number of osteoclasts around the interradicular alveolar bone showed chronological changes common to non-irradiated and irradiated animals. Several osteoclasts appeared one day after tooth extraction, and the maximal peak was observed 3 days after extraction. Local irradiation had no difference from non-irradiated controls. In animals receiving whole body irradiation, tooth extraction one day after irradiation caused smaller number of osteoclasts than that 7 day after irradiation during the experimental period. Whole body-irradiated rats had small osteoclasts with only a few nuclei and narrow resorption lacunae, indicating deficiency of radioresistant osteoclast precursor cells. Injection of intact bone marrow cells to whole body-irradiated animals immediately after tooth extraction recovered to some content the number of osteoclasts. These findings suggest that bone resorption in the wound healing of alveolar socket requires radioresistant, postmitotic osteoclast precursor cells from hematopoietic organs, but not from local sources around the alveolar socket, at the initial phase of wound healing. (author)

  14. Ibuprofen versus Acetaminophen in Controlling Postoperative Impacted Third Molar Tooth Extraction Pain

    International Nuclear Information System (INIS)

    Objectives: To compare the efficacy of ibuprofen and acetaminophen in reducing postoperative third molar extraction pain in patients reporting to Armed Forces Institute of Dentistry. Study design: Randomized controlled trial. Place and duration of study: The study was carried out on patients who presented for surgical removal of impacted teeth at Armed Forces Institute of Dentistry Rawalpindi (AFID) from February 2008 to March 2--9 at the Department of Oral Surgery, Armed Forces Institute of Dentistry Rawalpindi. Patients and methods: One hundred and forty patients requiring surgical removal of mandibular impacted teeth were equally divided into two groups. Surgical extraction of third molar tooth was performed under local anesthesia. Patients in group A were given ibuprofen and in group B were given acetaminophen at 6 hourly intervals. First dose was given 3 hours postoperatively. Each patient rated pain on a visual analog scale at baseline and then at 12, 24, 48 and 72 hours postoperatively. Results: There was statistically significant difference (p=0.025) during first 12 hours with ibuprofen group showing better efficacy but afterwards there was no significant difference in the efficacy of both drugs. Conclusions: Ibuprofen is more effective in controlling severe third molar extraction pain as compared to acetaminophen but has similar efficacy in controlling moderate pain. (author)

  15. The Use of Aloe Vera Extract as a Novel Storage Media for the Avulsed Tooth

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    Samaneh Badakhsh

    2014-07-01

    Full Text Available Background: Tooth avulsion is one of the most severe dental traumas which most often occur in children. When immediate replantation is not possible, storage in a proper media may lead to a prolonged survival rate. Aloe Vera is a cactus like plant with green, tapered leaves that are filled with a transparent viscous gel. This medicinal plant has significant anti-inflammatory, antioxidant, antibacterial and antifungal effects. The purpose of this study was to assess the effectiveness of different concentrations of Aloe Vera extract compared to DMEM (cell culture medium and egg white. Methods: The periodontal ligament (PDL cells were cultured and certain number of cells were treated with Aloe Vera extract (in four different concentrations, egg white and culture media for 1, 3, 6, and 9 hours. Cell viability was determined by using the (3-[4, 5-dimethylthiazolyl-2]-2, 5-diphenyltetrazolium bromide assay. Moreover, One-way ANOVA and post hoc (LSD test were used for analyzing the study groups. Results: The results indicate that culture media and Aloe Vera extract (10, 30, and 50% concentration were statistically similar and significantly preserved more PDL cells compared to other experimental storage media. Conclusion: Aloe Vera 10, 30, and 50% may be recommended as a suitable storage media for avulsed teeth.

  16. The influence of topic and systemic administration of copaiba oil on the alveolar wound healing after tooth extraction in rats

    OpenAIRE

    Dias-da-Silva, Marco A.; Pereira, Andresa C.; Marin, Miguel CC.; Salgado, Miguel AC.

    2013-01-01

    The Copaiba oil has been used as an auxiliary treatment of inflammations, skin disorders and stomach ulcers, however, in dentistry, this “alternative” medicine has not been investigated yet. The purpose of this study was to evaluate the influence of topic and systemic administration of copaiba oil on the alveolar wound healing after tooth extraction. Twenty-eight wistar male rats had their lower first molar teeth extracted. Subsequently, they were divided in four groups, according to the trea...

  17. An innovative approach to chair side provisional replacement of an extracted anterior tooth with Fiber Reinforced Ribbon Composite for space maintenance

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    Srinivas N CH

    2011-04-01

    Full Text Available An immediate replacement of an extracted anterior tooth may contribute to patients comfort, treatment acceptance and expectations of future treatment. However, fabrication of custom made restoration in the anterior region of the mouth through a removable or fixed may result in an esthetic compromise for patients during fabrication period. Chair side tooth replacement is an excellent short term option and one of the method is application of fiber reinforced composite resin technology. Though this method is used for reinforcing permanent tooth its use for primary teeth has not been reported. This article presents an innovative, affordable chair side procedure in which ribbon multipurpose bondable reinforcement ribbon is used to replace a single extracted tooth using patients own tooth.

  18. An innovative approach to chair side provisional replacement of an extracted anterior tooth with Fiber Reinforced Ribbon Composite for space maintenance

    OpenAIRE

    Srinivas N CH; Jayanthi M; Shanthan

    2011-01-01

    An immediate replacement of an extracted anterior tooth may contribute to patients comfort, treatment acceptance and expectations of future treatment. However, fabrication of custom made restoration in the anterior region of the mouth through a removable or fixed may result in an esthetic compromise for patients during fabrication period. Chair side tooth replacement is an excellent short term option and one of the method is application of fiber reinforced composite resin technology. Though t...

  19. Fabrication and anti-microbial evaluation of drug loaded polylactide space filler intended for ridge preservation following tooth extraction

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    Nebu George Thomas

    2011-01-01

    Full Text Available Background: The preservation or reduction of alveolar ridge resorption following tooth extraction is important in patients especially for those intended for implants at a later stage. One way to achieve this is by using membranes, graft materials, and biodegradable space fillers to prevent alveolar bone resorption and promote regeneration. A major attraction for using biodegradable and biocompatible polymers as space fillers for ridge preservation is their safety profile in comparison to xenograft materials like lyophilized bone and collagen. Materials and Methods: Biocompatible polylactide space fillers were fabricated by fusing porous polylactide particles. The sponges were loaded with drugs by placing them in the respective solutions. Pseudomonas aeruginosa was isolated from a chronic periodontitis patient and in vitro anti-microbial evaluation was done with the drug loaded sponges. Results: Chlorhexidine loaded space filler showed significant anti microbial effect against multiple drug resistant Pseudomonas aeruginosa isolated from a patient with chronic periodontitis. Conclusion: The results of this study indicate that biodegradable drug releasing polylactide space fillers has the potential to be used for ridge preservation following tooth extraction. Release of drugs in the socket may prove useful in preventing development of alveolar osteitis post extraction which can interfere with normal healing of the socket. Synthetic biodegradable polymers also exhibit a controlled degradation rate to achieve complete resorption within the intended time.

  20. The Use of Aloe Vera Extract as a Novel Storage Media for the Avulsed Tooth

    OpenAIRE

    Badakhsh, Samaneh; Eskandarian, Tahereh; Esmaeilpour, Tahereh

    2014-01-01

    Background: Tooth avulsion is one of the most severe dental traumas which most often occur in children. When immediate replantation is not possible, storage in a proper media may lead to a prolonged survival rate. Aloe Vera is a cactus like plant with green, tapered leaves that are filled with a transparent viscous gel. This medicinal plant has significant anti-inflammatory, antioxidant, antibacterial and antifungal effects. The purpose of this study was to assess the effectiveness of differe...

  1. Distinct subcutaneous emphysema following surgical wisdom tooth extraction in a patient suffering from 'Gilles de la Tourette syndrome'.

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    Tomasetti, Patrick; Kuttenberger, Johannes; Bassetti, Renzo

    2015-01-01

    Subcutaneous emphysema is a rare complication in oral surgery. In most cases, it resolves spontaneously. However, air might disperse into deeper facial spaces causing life-threatening complications such as compression of the tracheobronchial tree or the development of pneumomediastinum. Moreover, microorganisms might spread from the oral cavity into deeper spaces. Hence, rapid diagnosis of subcutaneous emphysema is important. Characteristic signs are both a shiftable swelling and crepitation. In this case report, a 30-year-old man, suffering from the Gilles de la Tourette Syndrome, with a distinct subcutaneous emphysema after bilateral surgical wisdom tooth extraction is presented. Induced by a specific motor tic, air accumulated from the periorbital through to the parapharyngeal region. Applying a 10-cm-long Redon drainage tube as air valve, 10 days after wisdom teeth extraction, the patient was asymptomatic with complete resolution of the emphysema. PMID:26077530

  2. The evaluation of the changes in blood pressure and pulse rate of hypertensive patients during tooth extraction.

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    Gungormus, M; Buyukkurt, M C

    2003-01-01

    The purpose of this investigation was to evaluate the changes in blood pressure and the pulse rate of hypertensive patients having dental extraction under a local anesthetic containing a vasopressor. The study included 64 patients (42 female and 22 male), 38 to 78 years of age. Twenty-six of the patients were normotensive, 38 were hypertensive patients. The hypertensive patients were identified as those patients who had histories of medically diagnosed high blood pressure and baseline recordings of blood pressures higher than 140/90 mm Hg. Articain HCl with 0.012 mg epinephrine hydrochloride, was used as the local anesthetic for all patients and one tooth was extracted from each patient. Blood pressure and pulse rate measurements were recorded immediately prior to anesthesia, just before extraction and 5 minutes after extraction. The data were analyzed by a two-way ANOVA with repeated measures. Analysis of the data indicated no statistically significant changes in the systolic and diastolic blood pressures and pulse rate for all interval measurements in both normotensive and hypertensive patients (P > 0.05). In this study, it was determined that there were no significant changes in the blood pressures and the pulse rate of hypertensive patients during surgical procedure, and one cartridge local anesthetic with articain HCl containing 0.012 mg pinephrine may be used safely in hypertensive patients with blood pressure equal or smaller than 154/99 mm Hg. PMID:15055158

  3. Oral health-related quality of life following non-surgical (routine tooth extraction: A pilot study

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    Wasiu L Adeyemo

    2012-01-01

    Full Text Available Aim: The study was designed to explore the changes in oral health-related quality of life (QoL in the immediate postoperative period following routine (non-surgical dental extraction. Setting and Design: A prospective study carried out at the Oral and Maxillofacial Surgery clinic of the Lagos University Teaching Hospital, Nigeria. Materials and Methods: Subjects attending who required non-surgical removal of one or two teeth under local anesthesia were included in the study. A baseline QoL questionnaire (oral health impact profile-14 [OHIP-14] was filled by each patient just before surgery, and only those who were considered to have their QoL "not affected" (total score 14 or less were included in the study. After the extraction, each subject was given a modified form of "health related QoL" [OHIP-14]-instrument to be completed by the 3 rd day-after surgery, and were given the opportunity to review the questionnaire on the 7 th day postoperative review. Results: Total OHIP-14 scores ranged between 14 and 48 (mean ± SD, 26.2 ± 8.3. Majority of the subjects (60% reported, "a little affected." Only few subjects (5.8% reported, "not at all affected," and about 32% reported, "quite a lot." Summation of OHIP-14 scores revealed that QoL was "affected" in 41 subjects (34.2% and "not affected" in 79 subjects (65.8%. More than 30% of subjects reported that their ability to chew, ability to open the mouth and enjoyment of food were affected following tooth extraction. Few subjects (14-34% reported deterioration in their speech and less than 20% of subjects reported that change in their appearance was "affected." Only few subjects (12.5-15.1% reported sleep and duty impairment. Thirty-percent of subjects reported their inability to keep social activities, and 41% were not able to continue with their favorite sports and hobbies. Multiple regression analysis revealed no significant association between age, sex, indications for extraction, duration of extraction, intra-operative complications, and deterioration in QoL ( P < 0.05. Consumption of analgesics beyond postoperative day 1 (POD1 was more common in subjects with socket healing complications than those without ( P = 0.000. About 33% of subjects reported, "inability to work" (1-3 days. Conclusion: About a third of subjects experienced significant deterioration in QoL. The most affected domains were eating/diet variation and speech variation. Therefore, patients should be informed of possible deterioration in their QoL following non-surgical tooth extraction.

  4. The influence of topic and systemic administration of copaiba oil on the alveolar wound healing after tooth extraction in rats.

    Science.gov (United States)

    Dias-da-Silva, Marco A; Pereira, Andresa C; Marin, Miguel Cc; Salgado, Miguel Ac

    2013-10-01

    The Copaiba oil has been used as an auxiliary treatment of inflammations, skin disorders and stomach ulcers, however, in dentistry, this "alternative" medicine has not been investigated yet. The purpose of this study was to evaluate the influence of topic and systemic administration of copaiba oil on the alveolar wound healing after tooth extraction. Twenty-eight wistar male rats had their lower first molar teeth extracted. Subsequently, they were divided in four groups, according to the treatment performed: (a) alveolar socket irrigation with copaiba oil; (b) alveolar socket irrigation with physiological serum; (c) daily gavage with copaiba oil or (d) daily gavage with physiological serum. After the sacrifice, the mandibles were removed and processed in order to obtain decalcified histological sections. The results demonstrated high level of epithelial migration, small number of inflammatory cells and vascular enhancement in the animals which received systemic administration of copaiba oil. The rats treated with topic administration of copaiba oil presented ulcerations and large number of inflammatory cells. An increased bone neoformation was observed in both groups treated with copaiba oil when compared with placebo group. It could be concluded that topic or systemic administration of copaiba oil leads to a better alveolar bone healing, however the topic application on connective tissue should be carefully considered, regarding the whole socket wound healing. Key words:Alveolar wound healing, oil-resin, copaiba. PMID:24455075

  5. The Effectiveness of a New Hemostatic Agent (Ankaferd Blood Stopper for the Control of Bleeding following Tooth Extraction in Hemophilia: A Controlled Clinical Trial

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    Hakk? O?uz Kazanc?o?lu

    2013-03-01

    Full Text Available Objective: To assess the hemostatic efficacy of a new local hemostatic agent, Ankaferd Blood Stopper (ABS, for the control of bleeding following tooth extraction in hemophiliacs. Materials and Methods: Simple tooth extractions were performed in 27 hemophilia A patients. In the treatment group (n=17 local hemostasis was achieved via application of ABS to the extraction sockets, whereas in the control group (n=10 local hemostasis was achieved via direct packing with gauze. Results: In all, 57 (21 primary and 36 permanent teeth extractions were performed in 27 hemophilia A patients. There were no significant differences in age or factor VIII level distribution between the 2 groups (p>0.05. The most significant clinical difference between the groups was associated with the use of ABS; those in the treatment group had significantly shorter duration of bleeding (p=0.002. Conclusion: This is the first study to evaluate the efficacy of ABS for the control of bleeding following tooth extraction in hemophiliacs. ABS can be considered an alternative local hemostatic agent for reducing clotting factor concentrates in hemophilia patients.

  6. Comparative Study of Acetaminophen, Ibuprofen and Combination Effects for Pain Relief Following Tooth Extraction in Children under Local Anesthesia

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    Z. Pahlavani

    2012-01-01

    Full Text Available Introduction & Objective: It is clear that tooth extraction is painful. Different drugs with various functions have been used in order to relieve the pain after extraction. Ibuprofen is a non-narcotic analgesic and acetaminophen is considered as one of the most consumption anti-inflammatory drugs and is administrated to relieve moderate to severe pains. Our purpose is comparing the effects of acetaminophen, ibuprofen and combination of them to relieve the teeth pain due to extraction under local anesthesia. Materials & Methods: In this randomized clinical trial, we divided 105 children (6-11 years old referred to pediatrics ward of dental faculty of Hamadan University into 3 groups of 35 after getting their parent's consents, taking, their history and weighing them. Group1: received acetaminophen syrup with dose of 15mg/kg, group2: received ibuprofen syrup with dose of 5 mg/kg, and group3 received acetaminophen syrup with dose of 7.5mg/kg and ibuprofen syrup with dose of 2.5mg/kg. . One hour before and 15 min after tooth extraction, severity of their pain was evaluated according to table(CHEOPS.Drug effects in every group was studied by c2 , t-test and Mann Whitney U test. Results: Age average of the children under survey in the group of acetaminophen syrup was 8.62±1.81 years old and in the group of ibuprofen syrup was 8.45±1.68 years old, and in the group of acetaminophen with ibuprofen was equal with 8.71±1.27 years old. Sex combination of the under survey children in the group of acetaminophen syrup was 51.4% / 48.6% (female/male, in the group of ibuprofen syrup was 51.4%/48.6%, and in the group of acetaminophen syrup with ibuprofen syrup was 65.7%/34.3%. Grade average of toothache immediately after extraction in the group treated with acetaminophen syrup was 33.19 and, in group treated with ibuprofen syrup equaled 37.81, and in the group treated with acetaminophen syrup with ibuprofen syrup was 47.86. Grade average of toothache 15 min after extraction in the group 1 was 35.1, in the second group was 35.9, and in the third group was 40.83.Conclusion: The group received ibuprofen syrup and in the group received acetaminophen syrup in comparison with the group received acetaminophen with ibuprofen on the instant and 15 min after extraction showed much more relieved effect (P<0.05. No meaningful statistic differences were observed between the group received acetaminophen I5 mg/kg and the group received ibuprofen 5 mg/kg.(Sci J Hamadan Univ Med Sci 2012;18(4:5-9

  7. Tooth Decay

    Science.gov (United States)

    ... in your mouth made up mostly of germs. Tooth decay starts in the outer layer, called the enamel. Without a filling, the decay can get deep into the tooth and its nerves and cause a toothache or ...

  8. Tooth anatomy

    Science.gov (United States)

    The visible portion of the tooth is the crown. The outer surface of the crown is made of enamel. Just beneath the enamel is dentin, a substance harder than bone. The gum surrounds the base (root) of the tooth. The ...

  9. Calcium dynamics in the healing of tooth extraction sockets in mice evaluated using 45Ca-autoradiography and Electron Probe Micro Analysis

    International Nuclear Information System (INIS)

    The calcium distribution in tooth extraction sockets of mice was examined using 45-Calcium autoradiography (ARG) and Electron Probe Micro Analysis (EPMA). Mice were divided into 8 groups (n=8) according to the number of days (1, 2, 3, 4, 5, 7, 10, 20 respectively) after extraction. Frozen sections were taken from mice on each experimental day after injection of 45-Calcium (RI). The process of formation of new bone was observed using ARG. An ultimate analysis was performed by EPMA. Histological analysis was performed with toluidine blue- and alizarin red S-staining. In toluidine blue-staining, an osteoblast was found along the socket wall at 4 days and non-calcified periodontal ligament was recognized until 5 days after extraction. In alizarin red S-staining, new bone was recognized separated from the socket wall at 4 days after extraction. 45Ca-labeling was detected strongly in the periosteum of the mandible, the surface of cement and periodontal ligament in control animals. 45Ca-labeling was moved from the bottom to the top of the tooth extraction socket during the period from 1 to 5 days after extraction, but in the periodontal ligament lower than in the granulation tissue. 45Ca-labeling was detected in the socket at 7, 10 and 20 days. At 4 days, calcium phosphate was observed in the central portion of the socket using EPMA. 45Ca-labeling showed deposition of calcium phosphate for alveolar bone and new bone. These results suggest that the granulation tissue may be involved in the initial calcification in the tooth extraction socket and lead to the formation of new bone in it. (author)

  10. Immediate Placement of Implants in Tooth Extraction Sockets in the Presence of Periapical Lesions with or without Er:YAG Laser Irradiation

    Directory of Open Access Journals (Sweden)

    Reza Birang

    2012-06-01

    Full Text Available Background and aims. Immediate placement of implant into fresh extraction sockets has become a common and accept-able clinical method. Different clinical studies have reported great success and survival rates in immediate implant placement in extraction sockets with periapical lesions. Theaim of this study was to investigate the effect of Er:YAG laser irradiation on success rate of immediate implant placement in tooth extraction sockets with chronic periapical lesions.Materials and methods. Thirty patients requiring a single-root tooth extraction with chronic periapical lesions were in-cluded in this prospective, randomized, clinical trial and divided into control (n=15 and test (n=15 groups. After tooth extrac-tion, the implant were placed with guided bone regeneration in the control group after periapical curettage and socket irrigation and in the test group, irrigation of the periapical region was accompaniedwith Er:YAG laser for 1 min at 100 mJ, 10 Hz, 12.73 J/cm2. Radiographic (using standard long-cone parallel and clinical parameters (plaque index [PI], modified bleeding index [mBI], probing depth [PD], keratinized mucosa [KM], Periotest values [PTV] were assessed at baseline and 1, 3 and 6 months after implant placement. Data was analyzed with t-test and chi-squared test. The level of significance was set at 5%.Results. A survival rate of 100% was observed for all the implants placed at the sixth-month follow-up, with no significant differences between clinical and radiographic parameters of the control and test groups at different time intervals (P>0.05.Conclusion. At 6-month follow-up, there were no complications in soft and hard tissue healing processes after immediate placement of implants into fresh extraction sockets with chronic periapical lesions, regardless of Er:YAG laser irradiation.

  11. Sobredentadura: alternativa terapéutica para disminuir las extracciones dentarias / Overdenture: therapeutic alternative to decrease tooth extractions

    Scientific Electronic Library Online (English)

    Mario, Castañeda Deroncelé.

    2014-11-01

    Full Text Available Se describe el caso clínico de una paciente de 45 años de edad, atendida en la Clínica Estomatológica Docente "José Luis Tassende" de Santiago de Cuba porque refería que en innumerables ocasiones se le fracturaban los dientes artificiales de la prótesis y la porción coronaria de la espiga del incisi [...] vo central superior derecho; también presentaba algunos dientes remanentes con facetas de desgastes en las caras palatinas, incisales y vestibulares, por lo cual se le realizó una prótesis parcial metálica (superior e inferior), con sobredentadura sobre dientes naturales. Con el proceder aplicado se evitaron las extracciones dentarias y se logró una adecuada rehabilitación estética y funcional Abstract in english The case report of a 45 year-old patient, assisted in "José Luis Tassende" Stomatological Clinic from Santiago de Cuba is described. She complained of fractures in countless occasions of the artificial teeth from her denture and the coronary portion of the pin of the central right superior incisor t [...] ooth; she also presented some residual teeth with facets of waste in the palatine, incisal and vestibular faces, reason why a metallic partial prosthesis (superior and inferior), with overdenture on her natural teeth was made. With this procedure, the teeth extractions were avoided and an appropriate aesthetic and functional rehabilitation was achieved

  12. Histometric study of socket healing after tooth extraction in rats treated with diclofenac / Estudo histométrico do reparo alveolar após extração dental em ratos tratados com diclofenaco

    Scientific Electronic Library Online (English)

    Luciana Ibara, Yugoshi; Miguel Angel, Sala; Luiz Guilherme, Brentegani; Teresa Lúcia Lamano, Carvalho.

    Full Text Available O objetivo do presente trabalho foi investigar se a administração de diclofenaco interfere no processo de reparo alveolar em ratos. Foram utilizados 42 ratos Wistar, dos quais 21 receberam 10mg/kg/dia de diclofenaco e o restante solução salina. Os animais foram submetidos a extração dos incisivos su [...] periores direito, e sacrificados 7, 14 e 21 dias após a avulsão dental. A formação progressiva de osso e a redução do volume de coágulo sangüíneo e tecido conjuntivo no período de 1 a 3 semanas após a extração dental foram quantificadas através do método histométrico de contagem de pontos. O tratamento com o diclofenaco causou significante atraso na neo-formação óssea, associado a um atraso na organização e remissão do coágulo sangüíneo. Abstract in english The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors [...] and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.

  13. The effect of red wine extract, resveratrol, on the degree and rate of orthodontic tooth movement in guinea pigs

    Directory of Open Access Journals (Sweden)

    Isidro Alex C Urriquia

    2015-01-01

    Full Text Available Objective: An animal trial, its protocol approved by the Institutional Animal Care and Use Committee of the U.P. National Institutes of Health (IACUC Protocol No. 2010-008, was employed to investigate the effects of resveratrol on the degree and rate of orthodontic tooth movement in guinea pigs. Materials and Methods: Eighteen male adult guinea pigs were randomly allocated into 3 groups: low dose, high dose, and control groups. A 0.016" titanium molybdenum alloy wire formed into a helical torsion spring with a coil, with the loops cemented onto the maxillary incisors of the animals, served as the orthodontic appliance. Daily oral administration of resveratrol was provided to the low dose (0.047 mg/kg and high dose (0.47 mg/kg groups, while water was provided to the control group. Measurements were taken everyday at the interproximal area at the level of the incisal edge using a measuring caliper. Results: The results of the ANOVA showed no statistically significant differences in the mean measurements of tooth separation among the three groups from day 2 (P=0.966 to day 8 (P=0.056. However, starting from day 9 (P=0.049 until day 18 (P=0.000, there was a significant difference in the mean tooth separation among the test groups. Conclusion: Using the LSD, it was noted that the low dose and the high dose groups have similar degrees of mean tooth separation, with the control group being significantly different from the two.

  14. Efeito comparativo entre clonixinato de lisina e paracetamol no controle da dor pós-exodontia / Comparison between lysine and paracetamol for post tooth extraction pain control

    Scientific Electronic Library Online (English)

    Klinger de Souza, Amorim; Lucas Celestino Guerzet, Ayres; Rafael Soares da, Cunha; Liane Maciel de Almeida, Souza; Mônica Silveira, Paixao; Francisco, Groppo.

    2012-12-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A exodontia é praticada desde os primórdios da humanidade como forma de resolver cirurgicamente os problemas dentários. Porém, como todo procedimento cirúrgico, ela promove um processo inflamatório reacional que se apresenta clinicamente com dor. Muitos fármacos têm sido u [...] sados no intuito de minimizar o desconforto pós-operatório, porém um protocolo para o seu controle ainda não está estabelecido. Este estudo teve como objetivo avaliar o efeito analgésico do clonixinato de lisina e paracetamol no controle de dor pós-exodontia. MÉTODO: Estudo duplamente encoberto e randomizado com 40 pacientes atendidos no Ambulatório de Cirurgia I no Departamento de Odontologia da Universidade Federal de Sergipe (DOD/UFS) que necessitaram de extrações por via alveolar em hemiarcadas diferentes utilizando clonixinato de lisina (125 mg) três vezes ao dia ou paracetamol (750 mg) quatro vezes ao dia, ambos por três dias no pós-operatório. A dor foi avaliada nas primeiras 24 e 48h com o uso da escala analógica visual. Os dados foram submetidos aos testes estatísticos t de Student e de Friedman. RESULTADOS: Não houve diferenças estatisticamente significantes entre idade, em relação aos gêneros e em relação à intensidade da dor. CONCLUSÃO: Tanto o clonixinato de lisina como o paracetamol foi eficaz para o controle da dor pós-exodontia. Abstract in english BACKGROUND AND OBJECTIVES: Tooth extraction is practiced since the early days of mankind to surgically solve dental problems. However, as any surgical procedure, it promotes an inflammatory reaction with clinical presentation of pain. Several drugs have been used to minimize postoperative discomfort [...] ; however there is still no established protocol for its control. This study aimed at evaluating the analgesic effect of lysine and paracetamol to control post tooth extraction pain. METHOD: Double blind randomized study with 40 patients seen by the Surgical Outpatient Setting I, Dentistry Department, Federal University of Sergipe (DOD/UFS), who needed alveolar extractions in different hemiarcades using lysine (125 mg) three times a day or paracetamol (750 mg) four times a day, both during three postoperative days. Pain was evaluated at 24 and 48 hours with the visual analog scale. Data were submitted to Student's t and Friedman statistical tests. RESULTS: There have been no statistically significant differences in age, gender and pain intensity. CONCLUSION: Both lysine and paracetamol were effective to control post tooth extraction pain.

  15. Treatment of an Unusual Non-Tooth Related Enamel Pearl (EP) and 3 Teeth-Related EPs with Localized Periodontal Disease Without Teeth Extractions: A Case Report.

    Science.gov (United States)

    Pardiñas López, Simón; Warren, Roger N; Bromage, Timothy G; Matei, Ioana Chesnoiu; Khouly, Ismael

    2015-09-01

    Enamel may be found ectopically as enamel pearls (EPs), which are frequently associated with advanced localized periodontal (LP) destruction. This study presents a case in which an unusual non-tooth-related enamel pearl and three teeth-related enamel pearls with LP disease were found and treated without teeth extractions. A 47-year-old female patient presented at the New York University College of Dentistry with four EPs, three of which were associated with periodontal pockets and/or bleeding on probing (BOP), and one of them not related to any tooth. Periodontal therapy included scaling and root planing and open flap debridement with removal of the EPs. Two pearls were histologically analyzed by polarizing microscopy and scanning electron microscope (SEM). Clinical periodontal parameters, including probing depth and BOP, were measured. All enamel found in the pearls had the same general morphologic appearance when examined by a SEM. The non-tooth-related pearl could be classified as Rodriguez Ponte "adamantinóidea" pearl. Probing depths at 3 months and 9 months after EP removal diminished considerably. Only after the treatment was there no BOP. Before treatment it was in some areas, as shown in Table 1. The LP related to the EP was resolved. The authors conclude that early recognition of enamel pearls is important in the prevention of periodontal destruction, and removal of EPs by a surgical approach as an adjunct to mechanical periodontal treatment resulted in resolution of the LP. The authors state that this is the first time an "adamantinóideas" pearl is being reported on clinically in the literature. PMID:26355443

  16. Intentional replantation of periodontally compromised hopeless tooth

    Directory of Open Access Journals (Sweden)

    G Nagappa

    2013-01-01

    Full Text Available Aesthetic considerations have influenced the management of dental maladies in varying degrees for many years. Even single tooth mal-alignment makes the patient to approach a dentist. Intentional replantation is a procedure in which an intentional tooth extraction is performed followed by reinsertion of the extracted tooth. Many authors agree that it should be reserved as the last resort to save a tooth after other procedures have failed or would likely to fail. The main reason of failure in replanted teeth is root resorption, specifically ankylosis or replacement resorption. Although the success rate is not always high, intentional replantation may be a treatment alternative that deserves consideration to maintain the natural dentition and avoid extraction of the tooth. Here is case report of a patient desiring alignment of malpositioned periodontally involved anterior single tooth due to various causes treated by intentional replantation.

  17. Dental Caries (Tooth Decay)

    Science.gov (United States)

    ... Find Data by Topic > Dental Caries (Tooth Decay) Dental Caries (Tooth Decay) Main Content Dental caries (tooth decay) remains the most prevalent chronic ... important source of information on oral health and dental care in the United States since the early ...

  18. Tooth - abnormal colors

    Science.gov (United States)

    ... or appear as spots or lines in the tooth enamel. Your genes affect your tooth color. Other things ... tea or coffee Genetic defects that affect the tooth enamel, such as dentinogenesis and amelogenesis High fever at ...

  19. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health Check Menstrual Calendar for Tooth Extraction What is ... is Dental Amalgam (Silver Filling)? Why is Oral Health Important for Men? Are You Biting Off More ...

  20. Life of a Tooth: A Visual Timeline

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    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health Temporomandibular Joint Disorder Check Menstrual Calendar for Tooth Extraction Why is Oral Health Important for Men? What is a Composite Resin ( ...

  1. Cigarette smoke inhalation influences bone healing of post-extraction tooth socket: a histometric study in rats

    Scientific Electronic Library Online (English)

    Ana Paula Oliveira, Giorgetti; João Batista, César Neto; Márcio Zaffalon, Casati; Enílson Antonio, Sallum; Francisco Humberto, Nociti Júnior.

    Full Text Available O objetivo do estudo foi avaliar a influência da inalação da fumaça de cigarros (IFC) sobre os períodos iniciais de reparo ósseo alveolar. Quarenta ratos Wistar foram aleatoriamente divididos em teste: animais expostos à IFC, que se iniciou 3 dias antes das extrações mantendo-se até o sacrifício (n= [...] 20)e controle (animais que não foram expostos à IFC; n=20). Os animais tiveram seus segundos molares inferiores extraídos bilateralmente (n=5/grupo/período) e foram sacrificados nos dias 3, 7, 10 e 14 dias após a cirurgia. Imagens digitalizadas foram analisadas de acordo com os seguintes parâmetros histométricos: tecido osteóide (OT), área remanescente (RA), tecido mineralizado (MT) e tecido não mineralizado (NMT) em cada alvéolo. Análise intergrupo mostrou que não houve diferença estatisticamente significante aos 3 dias (p>0,05) para todos os parâmetros. Aos 7 dias, a IFC influenciou negativamente (p?0,05) o preenchimento ósseo mostrando diferença estatisticamente significante para os parâmetros tecido não mineralizado e defeito remanescente (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, para controle e teste, respectivamente). No entanto, não houve diferença estatisticamente significante (p>0,05) aos 10 e 14 dias. Conclui-se que a IFC pode afetar o reparo ósseo alveolar inicial, o que pode ser crítico para a quantidade e qualidade da nova formação óssea em fumantes. Abstract in english The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sac [...] rifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7th day, CSI affected negatively (p0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.

  2. Exsanguinating bleeding following tooth extraction in a 12-year-old girl: a rare case of acquired haemophilia A.

    Science.gov (United States)

    Todo, Kimito; Ohmae, Tadaki; Osamura, Toshio; Kiyosawa, Nobuyuki; Sugimoto, Mitsuhiko; Shima, Midori; Imamura, Toshihiko; Imashuku, Shinsaku

    2015-12-01

    Acquired haemophilia A (AHA) is a life-threatening haemorrhagic disorder that occurs with various underlying conditions such as autoimmune disease, drug reactions, lymphoproliferative diseases, solid tumours and pregnancy/postpartum status. However, in half of all reported cases, the underlying disease is unknown. Most AHA cases develop in adults; paediatric/adolescent cases are extremely rare. The main clinical symptom is bleeding into the skin, muscles, soft tissues and/or mucous membranes. Here, we report the case of an otherwise healthy 12-year-old girl who presented with prolonged bleeding postexodontia. After being diagnosed with AHA, she was successfully treated with recombinant activated factor VII infusion and oral prednisolone. To avoid such unanticipated bleeding when performing dental extraction, preoperative haemostatic screening tests are recommended. PMID:26397882

  3. Fate of the buccal bone at implants placed early, delayed, or late after tooth extraction analyzed by cone beam CT : 10-year results from a randomized, controlled, clinical study

    DEFF Research Database (Denmark)

    Schropp, Lars; Wenzel, Ann

    2015-01-01

    AIM: To present 10-year cone beam CT (CBCT) data on the fate of buccal bone at single-tooth implants placed early, delayed, or late after tooth extraction. MATERIAL AND METHODS: Sixty-three of 72 patients, originally randomly allocated to three equal-size groups, received a single-tooth implant on average 10 days (Ea; N = 22), 3 months (De; N = 22), or 1.5 years (La; N = 19) after tooth extraction. Healing abutments were mounted after a 3-month period of submerged healing and metalceramic crowns were cemented after one additional month. At the second stage surgery, presence of buccal bone defects (dehiscences or intrabony) and their dimensions were registered. CBCT scans recorded with a Scanora(®) 3D unit and standardized periapical (PA) radiographs of the implants were obtained at the 10-year control. Interproximal bone levels (i.e., the distance from the implant platform to the first bone-to-implant contact; BIC) measured in CBCT image sections and PA were compared, and the buccal bone level was determinedin the CBCT images. RESULTS: Two Ea and one De implants failed to osseointegrate. Forty-nine patients attended the 10-year control and due to poor quality of 5 CBCT scans, useful CBCT images were available from 44 patients (Ea:12, De:17, La:15). No significant differences between CBCT and PA images in measurements of the interproximal bone levels were observed. Ten years after implant placement, BIC at the buccal aspect was located on average 2 mm apically to the implant platform (2.39 ± 1.06 mm [median = 2.36] for Ea, 2.22 ± 0.99 mm [median = 2.16] for De, and 1.85 ± 0.65 mm [median = 1.95] for La implants) with no significant difference among the groups (P = 0.20). Mean buccal bone level (bBL) for implants with an intrabony or a dehiscence defect at second stage surgery was 2.51 ± 1.12 mm [median = 2.70] and 2.84 ± 0.70 mm [median = 2.79], respectively, while 1.78 ± 0.74 mm [median = 1.93] for the implants with no defect. The difference in bBL between the implants without a defect and those with a dehiscence was significant at 10 years (P = 0.0005). CONCLUSION: Time of placement of single-tooth implants after tooth extraction did not significantly influence the peri-implant buccal bone level, while presence of a buccal bone dehiscence at second stage surgery resulted in significantly more apically located BIC buccally at 10 years.

  4. Preemptive analgesia of dexamethasone as compared to ketorolac tromethamine in simple tooth extractions / Analgesia preemptiva da dexametasona em relação ao cetorolaco de trometamol em extrações dentárias simples

    Scientific Electronic Library Online (English)

    Rodrigo Mathias Freire de Menezes, Carneiro; Rafael Soares da, Cunha; Liane Maciel de Almeida, Souza; Francisco, Groppo.

    2014-04-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Entendendo que a dor é o maior transtorno pós-operatório, diante da necessidade de estabelecer um protocolo terapêutico do seu controle pós-exodontias e dos poucos estudos comparando esses fármacos é que se justifica o trabalho. O objetivo deste estudo foi avaliar e compa [...] rar o efeito analgésico preemptivo de dois fármacos, ambos administrados em dose única. MÉTODOS: A pesquisa tem caráter experimental a partir de um ensaio clínico com seres humanos. Trata-se de um estudo duplamente encoberto, cruzado e randomizado, com 51 pacientes atendidos no Ambulatório de Cirurgia Oral do Departamento de Odontologia da Universidade Federal de Sergipe (DOD/UFS), entre setembro de 2011 e setembro de 2012, que necessitaram de extrações simples por via alveolar em hemiarcadas diferentes utilizando dexametasona (4mg) e cetorolaco de trometamol (10mg), uma hora antes da cirurgia distintamente. A dor foi avaliada nas primeiras 24 e 48h, com o uso da escala analógica visual. O intervalo de 8 dias foi estabelecido entre as exodontias. RESULTADOS: Não houve diferenças estatisticamente significantes no teste Exato de Fisher (p>0,05) e Friedman (p>0,05), nem entre os fármacos (considerando um mesmo período) nem entre os períodos (considerando o mesmo fármaco). CONCLUSÃO: Não existem diferenças significativas entre os fármacos e os períodos observados. Abstract in english BACKGROUND AND OBJECTIVES: Understanding that pain is the most important postoperative problem, in face to the need of establishing a therapeutic protocol to control post-tooth extraction pain and due to few studies comparing these drugs is that our study is justified. This study aimed at evaluatin [...] g and at comparing the preemptive analgesic effect of two drugs, both administered in bolus. METHODS: This is an experimental research as from a clinical trial with human beings. It is a double-blind, crossover and randomized trial with 51 patients seen by the Oral Surgery Ambulatory of the Dentistry Department, Federal University of Sergipe (DOD/UFS), between September 2011 and September 2012, who needed simple alveolar extractions in different hemiarcades, using dexamethasone (4mg) or ketorolac tromethamine (10mg), one hour before surgery distinctively. Pain was evaluated in the first 24 and 48 hours with the visual analog scale. The interval of eight days was established between extractions. RESULTS: There have been no statistically significant differences by Fisher (p>0.05) and Friedman (p>0.05) Exact tests, or between drugs (considering a same period) or between periods (considering the same drug). CONCLUSION: There are no significant differences between drugs and observed periods.

  5. Effect of acemannan, an extracted polysaccharide from Aloe vera, on BMSCs proliferation, differentiation, extracellular matrix synthesis, mineralization, and bone formation in a tooth extraction model.

    Science.gov (United States)

    Boonyagul, Sani; Banlunara, Wijit; Sangvanich, Polkit; Thunyakitpisal, Pasutha

    2014-07-01

    Aloe vera is a traditional wound healing medicine. We hypothesized acemannan, a polysaccharide extracted from Aloe vera gel, could affect bone formation. Primary rat bone marrow stromal cells (BMSCs) were treated with various concentrations of acemannan. New DNA synthesis, VEGF, BMP-2, alkaline phosphatase activity, bone sialoprotein, osteopontin expression, and mineralization were determined by [(3)H] thymidine incorporation assay, ELISA, biochemical assay, western blotting, and Alizarin Red staining, respectively. In an animal study, mandibular right incisors of male Sprague-Dawley rats were extracted and an acemannan treated sponge was placed in the socket. After 1, 2, and 4 weeks, the mandibles were dissected. Bone formation was evaluated by dual-energy X-ray absorptiometry and histopathological examination. The in vitro results revealed acemannan significantly increased BMSC proliferation, VEGF, BMP-2, alkaline phosphatase activity, bone sialoprotein and osteopontin expression, and mineralization. In-vivo results showed acemannan-treated groups had higher bone mineral density and faster bone healing compared with untreated controls. A substantial ingrowth of bone trabeculae was observed in acemannan-treated groups. These data suggest acemannan could function as a bioactive molecule inducing bone formation by stimulating BMSCs proliferation, differentiation into osteoblasts, and extracellular matrix synthesis. Acemannan could be a candidate natural biomaterial for bone regeneration. PMID:23315202

  6. Overview of Tooth Disorders

    Science.gov (United States)

    ... as when chewing or when tapped by a dental instrument. Pain in a tooth suggests tooth decay or gum disease. However, pain may also result when roots are exposed, when people chew too forcefully or ... CONSUMERS: ...

  7. Tooth Retained Implant: No More an Oxymoron

    Directory of Open Access Journals (Sweden)

    Divya Bhat

    2011-03-01

    Full Text Available Introduction: Periodontally af-fected teeth are treated in one of the two ways. (1 Tooth retention after periodontal surgery, in which the degree of regeneration achieved is unpredictable. (2 Tooth extrac-tion and implant placement. Implants have an osseointegrated surface which does not provide adequate shock absorption. Regeneration can be achieved by resecting the crown of the affected tooth and submerging the root. This technique has not had a clinical application so far as the tooth becomes difficult to restore. Placing an implant within the root can make the retained root restorable. At the same time, as the implant is placed within the root surface it achieves a periodontal integration which dampens occlusal forces better than osseointegration. Therefore, such a “tooth retained implant” may serve as an additional treatment option with significant benefits over tooth retention and implant placement alone. The hypothesis: Implants placed within retained roots have shown cementum deposition and attachment of periodontal ligament fibers over their surface. This periodontal attachment may be able to dam-pen forces better than in an osseointegrated implant. Moreover, since an implant is being placed, the crown of the tooth can be resected and submerged. This prevents epithelial migration, allows for the periodontal ligament cells to populate the wound and favors regeneration.Evaluation of the hypothesis: The technique of placing implants within cavities prepared in the root and then submerging them are simple for any practitioner placing implants routinely.

  8. Diagnosis of toothed gears

    Energy Technology Data Exchange (ETDEWEB)

    Bartelmus, W. (Poltegor Instytut, Wroclaw (Poland))

    1991-01-01

    Evaluates factors that influence wear of toothed gears used on equipment for mining and mine haulage in brown coal surface mines in Poland and methods for monitoring and diagnosing gear condition. The following aspects are analyzed: loads acting on toothed gears and interaction of gear elements, tooth durability, effects of design, technology and operating conditions on vibrations generated by gear systems, sources of mechanical vibrations and acoustic emission in toothed gears, characteristics of vibration signals, diagnostic methods, use of ferrography for diagnosis of gear condition, classification of wear phenomena and manifestations of gear wear, monitoring systems of gear condition, recommendations for monitoring and diagnostic systems. 37 refs.

  9. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Saturday, January 09, 2016 About | Contact InfoBites Quick Reference ... Learn more Children's Oral Health Check Menstrual Calendar for Tooth Extraction What is a Composite Resin (White Filling)? How Do I Care for My Child's Baby Teeth? Men: Looking for ...

  10. Life of a Tooth: A Visual Timeline

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    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health Check Menstrual Calendar for Tooth Extraction What is ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  11. Life of a Tooth: A Visual Timeline

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    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health Check Menstrual Calendar for Tooth Extraction Is My ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  12. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health Check Menstrual Calendar for Tooth Extraction What is ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  13. Life of a Tooth: A Visual Timeline

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    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health Check Menstrual Calendar for Tooth Extraction When Should ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  14. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Menstrual Calendar for Tooth Extraction Why is Oral Health Important for Men? How Do I Care for My Child's Baby Teeth? Headaches and Jaw Pain? Check Your Posture! Learn what those dental words mean. The Life of a ... | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  15. Tooth-Colored Fillings

    Science.gov (United States)

    ... materials and both the enamel and dentin. Restorative dentistry recreates a tooth that not only looks natural ... Using Nature as a Guide In the past, dentistry focused on creating “stronger” teeth by using very ...

  16. Seal Out Tooth Decay

    Science.gov (United States)

    ... Besides sealants, are there other ways to prevent tooth decay? How can I get dental sealants for my children? What are dental sealants? Sealants are thin, plastic coatings painted on the chewing surfaces of the back ...

  17. Alveolar Ridge Conservation by Early Bone Formation After Tooth Extraction in Rabbits: A Histomorphological Study / Conservación de la Cresta Alveolar por Formación Ósea Temprana después de la Extracción Dentaria en Conejos: Un Estudio Histomorfológico

    Scientific Electronic Library Online (English)

    Mario, Cantín; Sergio, Olate; Ramón, Fuentes; Bélgica, Vásquez.

    2015-03-01

    Full Text Available La pérdida de volumen cresta alveolar, es un proceso irreversible. Para evitar este evento fisiológico, que típicamente resulta en cambios anatómicos locales significativos, tanto en la dimensión horizontal y vertical, existen algunos procedimienos para reducir al mínimo la pérdida de volumen óseo q [...] ue sigue típicamente a la extracción del diente. El propósito de este estudio fue evaluar si tres injertos óseos diferentes podrían promover la formación de hueso en el alveolo tras la extracción del diente para la conservación de la cresta alveolar. Los primeros molares mandibulares de conejos machos adultos fueron extraídos y los alvéolos post extracción fueron rellenados aleatoriamente con tres injertos óseos diferentes, uno de xenoinjerto y dos injertos aloplásticos, más un grupo que no recibió tratamiento (coágulo de sangre). Los alvéolos post extracción en los conejos seleccionados de cada grupo fueron evaluados a las 4, 6, o 8 semanas post-extracción. Los resultados indicaron que los alvéolos tratados con injerto aloplástico mostraron formación de hueso lamelar (6,5%) ya a las 4 semanas post extracción. Por otra parte, el grado de formación de hueso nuevo fue significativamente mayor (P Abstract in english Alveolar ridge volume loss is an irreversible process. To prevent this physiological event, which typically result in significant local anatomical changes in both the horizontal and the vertical dimension, some strategies are indicated to minimize the loss of ridge volume that typically follows toot [...] h extraction. The purpose of this study was to evaluate if three different bone grafts could promote new bone formation in the alveolar socket following tooth extraction for the alveolar ridge conservation. First mandibular molars of male adults rabbits were extracted and the extraction sockets were randomly treated with three different bone grafts, one xenograft and two alloplastic grafts, and a group that received no treatment (blood clot). The extraction sockets of selected rabbits from each group were evaluated at 4, 6, or 8-week post-extraction. The results indicated that the extraction sockets treated with alloplastic graft (biphasic calcium phosphate) exhibited lamellar bone formation (6.5%) as early as four weeks after the extraction was performed. Moreover, the degree of new bone formation was significantly higher (P

  18. The effect of permanent grafting materials on the preservation of the buccal bone plate after tooth extraction: an experimental study in the dog.

    LENUS (Irish Health Repository)

    Bashara, Haitham

    2012-08-01

    The aim of the present study was to evaluate the effects of a novel bone substitute system (Natix(®)), consisting of porous titanium granules (PTG) and a bovine-derived xenograft (Bio-Oss(®)), on hard tissue remodelling following their placement into fresh extraction sockets in dogs.

  19. Radiation dosimetry of tooth enamels with electron spin resonance (ESR)

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR) dosimetry method using tooth enamel was developed as to detect the minimum radiation dose of around 10 mGy. The main broad signal component must be subtracted from the ESR spectrum to get the signal induced by radiation. Dosimetry of residents close to Chernobyl reactor accident was made using eight tooth pieces with ESR. The obtained dose ranges from about 20 mSv to about 70 mSv including the effect of natural radiation and the dental X-rays. The ESR dosimetry system was developed to measure, the cumulative radiation dose in a tooth without extraction. (author)

  20. An electron spin resonance system for in-vivo human tooth dosimetry

    International Nuclear Information System (INIS)

    An electron spin resonance (ESR) dosimetry system for an in-vivo human tooth has been developed to measure, without extraction, the cumulative radiation dose in a tooth. The system consists of a TE102 cavity with an aperture at the end plate, a Nd-B-Fe (Neomax) oral magnet and a commercial ESR spectrometer. The front molar is attached to the aperture of the cavity to detect radicals created by radiation in the tooth enamel. Optimum dosimetry conditions were investigated using an extracted human tooth. (author)

  1. Three tooth kinematic coupling

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Layton C. (Livermore, CA)

    2000-01-01

    A three tooth kinematic coupling based on having three theoretical line contacts formed by mating teeth rather than six theoretical point contacts. The geometry requires one coupling half to have curved teeth and the other coupling half to have flat teeth. Each coupling half has a relieved center portion which does not effect the kinematics, but in the limit as the face width approaches zero, three line contacts become six point contacts. As a result of having line contact, a three tooth coupling has greater load capacity and stiffness. The kinematic coupling has application for use in precision fixturing for tools or workpieces, and as a registration device for a work or tool changer or for optics in various products.

  2. Saw-tooth cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Karatza Ageliki A

    2009-12-01

    Full Text Available Abstract We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV, dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interventricular septum and lateral LV wall, along with areas of hypokinesis at the LV septum and apex in a noncoronary distribution, without any late gadolinium enhancement. We have termed this condition saw-tooth cardiomyopathy because of the very characteristic appearance.

  3. The Rachitic Tooth

    OpenAIRE

    Foster, Brian L; Nociti, Francisco H.; Somerman, Martha J.

    2013-01-01

    Teeth are mineralized organs composed of three unique hard tissues, enamel, dentin, and cementum, and supported by the surrounding alveolar bone. Although odontogenesis differs from osteogenesis in several respects, tooth mineralization is susceptible to similar developmental failures as bone. Here we discuss conditions fitting under the umbrella of rickets, which traditionally referred to skeletal disease associated with vitamin D deficiency but has been more recently expanded to include new...

  4. Saw-tooth cardiomyopathy

    OpenAIRE

    Karatza Ageliki A; Danias Peter G; Davlouros Periklis A; Kiaffas Maria G; Alexopoulos Dimitrios

    2009-01-01

    Abstract We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV), dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interve...

  5. Autogenous transplantation of mandibular third molar to replace tooth with vertical root fracture

    OpenAIRE

    Asgary, Saeed

    2009-01-01

    Autogenous tooth transplantation (ATT) can be considered when there is a hopeless molar tooth and suitable donor present. This report presents an unconventional case of successful ATT of a third molar replacing the adjacent fractured second molar in a 33 year old woman. This wisdom tooth had completely developed roots. Root-end filling with Calcium Enriched Mixture (CEM) cement was performed in the third molar. The second molar was extracted non-traumatically without any bone removal; the wis...

  6. Clinical measurement of tooth wear: Tooth wear indices

    OpenAIRE

    López-Frías, Francisco J.; Castellanos-Cosano, Lizett; Martín-González, Jenifer; Llamas-Carreras, José M.; Segura-Egea, Juan J.

    2012-01-01

    Attrition, erosion, and abrasion result in alterations to the tooth and manifest as tooth wear. Each classification corresponds to a different process with specific clinical features. Classifications made so far have no accurate prevalence data because the indexes do not necessarily measure a specific etiology, or because the study populations can be diverse in age and characteristics. Tooth wears (attrition, erosion and abrasion) is perceived internationally as a growing problem. However...

  7. The Human Sweet Tooth

    OpenAIRE

    McDaniel Amanda H; Reed Danielle R

    2006-01-01

    Abstract Humans love the taste of sugar and the word "sweet" is used to describe not only this basic taste quality but also something that is desirable or pleasurable, e.g., la dolce vita. Although sugar or sweetened foods are generally among the most preferred choices, not everyone likes sugar, especially at high concentrations. The focus of my group's research is to understand why some people have a sweet tooth and others do not. We have used genetic and molecular techniques in humans, rats...

  8. Mechanics analysis of molar tooth splitting.

    Science.gov (United States)

    Barani, Amir; Chai, Herzl; Lawn, Brian R; Bush, Mark B

    2015-03-01

    A model for the splitting of teeth from wedge loading of molar cusps from a round indenting object is presented. The model is developed in two parts: first, a simple 2D fracture mechanics configuration with the wedged tooth simulated by a compact tension specimen; second, a full 3D numerical analysis using extended finite element modeling (XFEM) with an embedded crack. The result is an explicit equation for splitting load in terms of indenter radius and key tooth dimensions. Fracture experiments on extracted human molars loaded axially with metal spheres are used to quantify the splitting forces and thence to validate the model. The XFEM calculations enable the complex crack propagation, initially in the enamel coat and subsequently in the interior dentin, to be followed incrementally with increasing load. The fracture evolution is shown to be stable prior to failure, so that dentin toughness, not strength, is the controlling material parameter. Critical conditions under which tooth splitting in biological and dental settings are likely to be met, however rare, are considered. PMID:25584989

  9. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  10. Immediate natural tooth pontic: A viable yet temporary prosthetic solution: A patient reported outcome

    Directory of Open Access Journals (Sweden)

    Sudhir Bhandari

    2012-01-01

    Conclusion: The concept of immediate pontic placement is surely a viable treatment option and promises an excellent transient esthetic solution for a lost tooth as well as enables good preparation of the extraction site for future prosthetic replacement.

  11. Treatment of localized lesion of the tooth and surrounding tissue caused by dental disharmony: Case report

    OpenAIRE

    An?elkovi? Slobodan; Divni?-Resnik Tihana; ?i?i? Snežana

    2010-01-01

    The loss of proper contact of the adjacent teeth, which usually occurs as a result of caries or tooth extraction, can lead to serious consequences on oral tissues health as well as on the function of complete oral system, unless timely repaired. It often happens that the irregular contact of the tooth due to inadequate filling remains unnoticed by the patient and dentist. Also, if the loss of contact caused by caries or after tooth extraction is not treated, it often leads to inclination of a...

  12. Efecto In Vitro de las Bebidas Refrescantes sobre la Mineralización de la Superficie del Esmalte Dentario de Piezas Permanentes Extraídas / In Vitro Effect of Refreshing Drinks on the Mineralization of Tooth Enamel Surface in Extracted Permanent Dental Pieces

    Scientific Electronic Library Online (English)

    Ximena, Moreno Ruiz; Carmen Gloria, Narváez Carrasco; Verónica, Bittner Schmidt.

    2011-08-01

    Full Text Available El objetivo de este estudio fue determinar el efecto de las bebidas refrescantes sobre la mineralización de la superficie del esmalte de piezas dentarias permanentes extraídas. Para esto se realizó un estudio experimental donde la muestra correspondió a 50 cortes de premolares permanentes extraídos [...] en estado íntegro, estos fueron distribuidos en tres grupos de estudio mediante asignación aleatoria: bebidas gaseosas, jugos y néctares, y aguas minerales purificadas y saborizadas más un grupo control. Los dientes fueron lavados y almacenados en saliva artificial a 4°C. A todos los cortes dentarios se les midió la mineralización con el equipo Diagnodent 2095 (Kavo®) antes de iniciar la exposición, la cual correspondió a un minuto en el tipo de bebida según grupo, seguido por tres minutos en saliva artificial, ciclo que se repitió cinco veces en un tiempo de 20 minutos. Este procedimiento se realizó una vez al día, por un mes y para cada día se utilizaron nuevas bebidas refrescantes. Una vez finalizado se volvió a medir la mineralización para luego realizar las comparaciones entre grupos. El grupo de bebidas gaseosas provocó una mayor desmineralización en la superficie del esmalte dentario (p=0,000), seguido del grupo de jugos y néctares (p=0,000). El grupo de aguas minerales saborizadas y purificadas no provocaron efectos sobre la mineralización de la superficie del esmalte. Por lo tanto, sólo el grupo de gaseosas y jugos provocaron un efecto desmineralizador en la superficie del esmalte de las piezas dentarias, siendo la Coca-cola® la que produjo mayor efecto seguido de la Coca-cola light® y luego el Kapo®. Abstract in english The aim of this study was to determine the effect of refreshing drinks on the mineralization of tooth enamel surface in extracted permanent dental pieces. For this an experimental study was conducted where the sample was composed by 50 permanent premolars extracted as an entire piece. These pieces w [...] ere randomly distributed in three study groups: soft drinks, juices and nectars, and purified and flavored mineral waters, in addition to a control group. The teeth were carefully washed and stored in artificial saliva at 4 C. Before starting the exposure to refreshing drinks, all dental slices were tested in order to measure their baseline mineralization using the Diagnodent 2095 equipment (Kavo®). The exposition consisted in one minute of contact with the drink corresponding to each group, followed of three minutes in artificial saliva. This cycle was repeated 5 times in 20 minutes time. This procedure was carried out once daily, for one month, and every day new refreshing drinks were used. Once the assay finished, the premolar mineralization was measured again, in order to make comparisons between groups. The soft drinks group caused the highest demineralization on the teeth enamel surface (p=0.000), followed by the juices and nectars group (p=0.000). In the purified and flavored mineral waters group, no effects were found on the mineralization of the enamel surface. A demineralizing effect on the enamel surface of dental pieces was observed only in the groups of soft drinks and juices, where Coca-Cola® caused the highest effect, followed by Coca-Cola light® and then Kapo®.

  13. Resection of the Tooth Apex with Diode Laser

    Directory of Open Access Journals (Sweden)

    Uzunov Tz.

    2014-06-01

    Full Text Available An “in vitro” experimental study has been carried out on 70 extracted teeth. A laser resection of the root apex has been carried out with diode laser beam with a wavelength of - 810 ± 10 nm. Sequentially a radiation with increasing power has been applied, as follows: 1,3 W, 2W, 3W, 4W, 5W, 6W, 7W, in electro surgery mode. Successful resection of the tooth apex has been performed at: 3W; 4W; 5W; 6W and 7W power. It was established that when laser resected the tooth apex carbonizes.

  14. Traumatic Intrusion of a Maxillary Canine Tooth: 3 Cases.

    Science.gov (United States)

    Edstrom, Emily J; Smith, Mark M; Taney, Kendall; Smithson, Christopher W

    2015-01-01

    Of the six recognized types of tooth luxation injuries, intrusion generally carries the most guarded long-term prognosis due to the high risk of complications, including root resorption, ankylosis, marginal bone loss, and pulp canal obliteration or necrosis. The degree of traumatic intrusion and stage of root development affects the outcome and treatment planning. This report describes the clinical history, oral and radiographic examination findings, and rationale for surgical extraction in 2 dogs and 1 cat with traumatic intrusion of a maxillary canine tooth. PMID:26197689

  15. Immediate implantation in infected tooth sockets.

    Science.gov (United States)

    Viski?, Josko; Milardovi?, Sladana; Katanec, Davor; Vojvodi?, Denis; Mehuli?, Ketij

    2011-03-01

    Although immediate implantation has not been previously recommended in infected sites, it is now becoming a procedure of choice in modern implant dentistry. We report a case of a 65-year-old male patient, who required multiple tooth extractions in the lower jaw and fabrication of a new overdenture in the lower jaw and a complete denture in the upper jaw. Immediate implantation in infected tooth sockets followed extraction. Two NobelReplace Tapered implants (Nobel BioCare, Zürich, Switzerland), one 13 mm long and 4.3 mm wide and the other 13 mm long and 5.0 mm wide, were placed in the position 33 and 43. The site was sutured and a temporary denture was fabricated by adjusting the old denture. After a period of three months the implant site was reopened and healing abutments were placed. Impressions were made using the Impregum Penta Soft (3M ESPE, St. Paul, Minn, USA) polyether material. Ball Abutment Titanium" was used as a patrix attachment and a matrix was inserted into the denture. Clinical examination and x-ray analysis after six months showed no significant changes of the implants. Bone resorption was within standard values. Although it is still a controversial subject, immediate implantation in infected sites can be a safe and predictable procedure if surgical protocols are followed. However, further research is needed to draw firm conclusions. PMID:21661375

  16. NSAIDs in orthodontic tooth movement

    OpenAIRE

    Karthi, Muthukumar; Anbuslevan, Gobichettipalyam Jagtheeswaran; Senthilkumar, Kullampalyam Palanisamy; Tamizharsi, Senthilkumar; Raja, Subramani; Prabhakar, Krishnan

    2012-01-01

    Orthodontic tooth movement is basically a biological response toward a mechanical force. The movement is induced by prolonged application of controlled mechanical forces, which create pressure and tension zones in the periodontal ligament and alveolar bone, causing remodeling of tooth sockets. Orthodontists often prescribe drugs to manage pain from force application to biologic tissues. Nonsteroidal anti-inflammatory drugs (NSAIDs) are the drugs usually prescribed. NSAIDs block prostaglandin ...

  17. Biomaterial Selection for Tooth Regeneration

    OpenAIRE

    Yuan, Zhenglin; Nie, Hemin; WANG Shuang; Lee, Chang Hun; Li, Ang; Fu, Susan Y.; Zhou, Hong; Chen, Lili; Mao, Jeremy J.

    2011-01-01

    Biomaterials are native or synthetic polymers that act as carriers for drug delivery or scaffolds for tissue regeneration. When implanted in vivo, biomaterials should be nontoxic and exert intended functions. For tooth regeneration, biomaterials have primarily served as a scaffold for (1) transplanted stem cells and/or (2) recruitment of endogenous stem cells. This article critically synthesizes our knowledge of biomaterial use in tooth regeneration, including the selection of native and/or s...

  18. From hopeless to good prognosis: journey of a failing tooth.

    Science.gov (United States)

    Gupta, Saurabh; Deshmukh, Jeevanand; Khatri, Richa; Kulkarni, Vinaya Kumar; Karthik, B

    2015-02-01

    Chronic periodontitis, along with associated clinical findings such as pathologic tooth migration, diastema, functional and aesthetic aberrations, poses an immense challenge to a dental professional. These findings convert clinical decision making into a daunting task and adversely affect the prognosis and the treatment plan for the presenting clinical problem. An interdisciplinary approach aimed at restoring functional and aesthetic needs of the affected individual within the limitations of such a compromised clinical scenario may be a viable alternative to any radical treatment causing loss of natural tooth structure such as extraction. This article reports the usefulness of the interdisciplinary route for managing an otherwise hopeless clinical situation of chronic periodontitis complicated with extreme mobility and pathologic tooth migration, which resulted in compromised function and aesthetics. PMID:25859109

  19. Patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment

    DEFF Research Database (Denmark)

    Hartlev, Jens; Kohberg, Peter; Ahlmann, Søren; Andersen, Niels T; Schou, Søren; Isidor, Flemming

    2014-01-01

    OBJECTIVES: To assess patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment and a provisional crown followed by later placement of a definitive crown. MATERIALS AND METHODS: In private practice, a single-tooth implant was placed immediately after tooth extraction in the esthetic zone of 54 patients. A definitive individual abutment and a provisional crown were mounted in the same visit. The d...

  20. Functional tooth restoration utilising split germs through re-regionalisation of the tooth-forming field.

    Science.gov (United States)

    Yamamoto, Naomi; Oshima, Masamitsu; Tanaka, Chie; Ogawa, Miho; Nakajima, Kei; Ishida, Kentaro; Moriyama, Keiji; Tsuji, Takashi

    2015-01-01

    The tooth is an ectodermal organ that arises from a tooth germ under the regulation of reciprocal epithelial-mesenchymal interactions. Tooth morphogenesis occurs in the tooth-forming field as a result of reaction-diffusion waves of specific gene expression patterns. Here, we developed a novel mechanical ligation method for splitting tooth germs to artificially regulate the molecules that control tooth morphology. The split tooth germs successfully developed into multiple correct teeth through the re-regionalisation of the tooth-forming field, which is regulated by reaction-diffusion waves in response to mechanical force. Furthermore, split teeth erupted into the oral cavity and restored physiological tooth function, including mastication, periodontal ligament function and responsiveness to noxious stimuli. Thus, this study presents a novel tooth regenerative technology based on split tooth germs and the re-regionalisation of the tooth-forming field by artificial mechanical force. PMID:26673152

  1. Restauración inmediata de un implante único post-extracción con presencia de una lesión radicular lateral / Immediate restoration of a single implant placed after tooth extraction with lateral root lesion

    Scientific Electronic Library Online (English)

    José Raúl, Blanco; Felix Alejandro, Mejía; Luis Felipe, Restrepo.

    2013-01-01

    Full Text Available La perdida de un diente en la zona estética anterior y su reemplazo con una restauración implanto soportada representa uno de los mayores desafíos estéticos y funciónales en el campo de la Implantología moderna.La evidencia actual respalda la provisionalización inmediata de un implante después de su [...] inserción con tasas de éxito comparables con las de los protocolos tradicionales utilizados recientemente. Siegenthaler y col, concluyeron que para aquellos implantes donde se alcanzó estabilidad primaria, la colocación de implantes inmediatos en alvéolos postextracción que presentaban lesiones periapicales no conllevó a un aumento en la tasa de complicaciones y resultó en una integración igualmente favorable en comparación con el grupo control. La adecuada selección del caso para este tipo de protocolos es fundamental y debe estar regido por una filosofía clara de Preservación. La preservación de las estructuras orales existentes en el área a intervenir exige un enfoque terapéutico netamente conservador que favorezca un resultado final favorable y exitoso. La paciente tratada es una de 40 años de edad que acude al postgrado de rehabilitación oral de la Universidad CES de Medellín, Colombia cuyo motivo de consulta fue "Para revisión recomendada por periodoncia" según sus propias palabras. Al momento del examen clínico intraoral se observó encía edematizada a nivel de #11 con profundad al sondaje de 10 mm en DP sospechando una fractura vertical que se corroboró con el análisis de la radiografía periapical. Se le planteó claramente a la paciente las distintas opciones de tratamiento por la pérdida del incisivo central superior con las posibles complicaciones y riesgos que se podrían presentar. La paciente aceptó la opción del implante inmediato postextracción con provisionalización y procedió a firmar el consentimiento informado de la historia clínica. Conclusiones: La provisionalización inmediata del implante brinda beneficios adicionales para la integración de los tejidos blandos, ofreciendo unos resultados estéticos de alta calidad. La colocación de implantes inmediatos en alvéolos con procesos infecciosos periapicales tiene un porcentaje de éxito prometedor a corto plazo. Abstract in english The lost of an anterior tooth and it replacement with a retained implant restoration is one of the mayor functional and aesthetic challenges in modern implantogy. Actual Evidence support that immediate implant provisionalization compare with the traditional protocols have similar results in success [...] rates. Siegenthaler y col conclude that in situations when the primary stabilization is obtained, the implant placement in fresh sockets with cronical periapical lesions have similar results versus control group. Carefull must be taken in the case selection for this modern protocol and should be done under the preservation philosophy. The integrity of remaining bone structures and soft tissue is the main goal for the success of this technique. Female patient, 40 years old, who attended the program of oral rehabilitation at the University of CES Medellin, Colombia, whose reason for consultation was "To review recommended by periodontics" in his own words. At the time of clinical examination intraoral gum edema was observed at # 11 with probing 10 mm in DP suspecting a vertical fracture who was corroborated with the analysis of the periapical X-ray. The different treatment options were stated clearly to the patient for the loss of the maxillary central incisor with the possible complications and risks that could arise. The patient agreed to the immediate post-extraction implant option with temporization and proceeded to sign the informed consent of the medical record. Conclusions: The placement of implants immediate with infectious processes periapicals has a success rate in the short term very promising. The immediate provisionalization implant provides additional benefits for the integration of soft tissues, offering some high-quality aesthetic results.

  2. Parameters of tooth enamel spin model and its application in EPR-dosimetry

    International Nuclear Information System (INIS)

    The authors present a model of spin system of tooth enamel EPR spectra which include two types of parametric centres with axial anisotropy. Spectra of 126 samples of tooth enamel with absorbed dose of 4000 mGy of Co-60 gamma-radiation were investigated basing on the parameters of the model with the use of EPR PS-100X radio spectrometer. The suggested model and the results of measurement of the EPR signal noise component with PS-100X radio spectrometer were used to calculate the error of the absorbed doses in tooth enamel with least-aqua res technique. Optimal conditions for investigation of tooth enamel with EPR PS-100X radio spectrometer were determined. Sensitivity of absorbed dose measurement in tooth enamel at the level of 10-15 mGy was evaluated. The error of absorbed dose calculation was shown not to depend considerably on the degree of dentine extraction from the samples

  3. Tooth polishing: The current status

    Directory of Open Access Journals (Sweden)

    Madhuri Alankar Sawai

    2015-01-01

    Full Text Available Healthy teeth and gums make a person feel confident and fit. As people go about their daily routines and with different eating and drinking habits, the tooth enamel turns yellowish or gets stained. Polishing traditionally has been associated with the prophylaxis procedure in most dental practices, which patients know and expect. However, with overzealous use of polishing procedure, there is wearing of the superficial tooth structure. This would lead to more accumulation of local deposits. Also, it takes a long time for the formation of the fluoride-rich layer of the tooth again. Hence, now-a-days, polishing is not advised as a part of routine oral prophylaxis procedure but is done selectively based on the patients? need. The article here, gives an insight on the different aspects of the polishing process along with the different methods and agents used for the same.

  4. Tooth polishing: The current status.

    Science.gov (United States)

    Sawai, Madhuri Alankar; Bhardwaj, Ashu; Jafri, Zeba; Sultan, Nishat; Daing, Anika

    2015-01-01

    Healthy teeth and gums make a person feel confident and fit. As people go about their daily routines and with different eating and drinking habits, the tooth enamel turns yellowish or gets stained. Polishing traditionally has been associated with the prophylaxis procedure in most dental practices, which patients know and expect. However, with overzealous use of polishing procedure, there is wearing of the superficial tooth structure. This would lead to more accumulation of local deposits. Also, it takes a long time for the formation of the fluoride-rich layer of the tooth again. Hence, now-a-days, polishing is not advised as a part of routine oral prophylaxis procedure but is done selectively based on the patients' need. The article here, gives an insight on the different aspects of the polishing process along with the different methods and agents used for the same. PMID:26392683

  5. On gear tooth stiffness evaluation

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; JØrgensen, Martin Felix

    2014-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact width is constant. © 2014 Elsevier Ltd. All rights reserved.

  6. Osteoimmunology in orthodontic tooth movement.

    Science.gov (United States)

    Jiang, C; Li, Z; Quan, H; Xiao, L; Zhao, J; Jiang, C; Wang, Y; Liu, J; Gou, Y; An, S; Huang, Y; Yu, W; Zhang, Y; He, W; Yi, Y; Chen, Y; Wang, J

    2015-09-01

    The skeletal and immune systems share a multitude of regulatory molecules, including cytokines, receptors, signaling molecules, and signaling transducers, thereby mutually influencing each other. In recent years, several novel insights have been attained that have enhanced our current understanding of the detailed mechanisms of osteoimmunology. In orthodontic tooth movement, immune responses mediated by periodontal tissue under mechanical force induce the generation of inflammatory responses with consequent alveolar bone resorption, and many regulators are involved in this process. In this review, we take a closer look at the cellular/molecular mechanisms and signaling involved in osteoimmunology and at relevant research progress in the context of the field of orthodontic tooth movement. PMID:25040955

  7. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Wednesday, November 18, ... is Baby Bottle Tooth Decay? Learn what those dental words mean. The Life of a Tooth games ...

  8. Immediate Implant in Management of Anterior Missing Tooth

    Directory of Open Access Journals (Sweden)

    Harinath Reddy S

    2010-04-01

    Full Text Available Immediate implant placement after extraction has become a favored treatment protocol with many clinicians worldwide. There are many advantages to this protocol, amongst them; shortened treatment time, placement of the implant in sound bone that constitutes the socket wall, placement trajectory guidance by the socket and preservation of bone volume. This case report describes the management of an anterior missing tooth using immediate implant. The result was good, which further validate the use of this technique for suitable patient management.

  9. Accelerated orthodontic tooth movement: molecular mechanisms.

    Science.gov (United States)

    Huang, Hechang; Williams, Ray C; Kyrkanides, Stephanos

    2014-11-01

    Accelerating orthodontic tooth movement can significantly reduce treatment duration and risks of side effects. The rate of orthodontic tooth movement is chiefly determined by the remodeling of tissues surrounding the roots; this in turn is under the control of molecular mechanisms regulating cellular behaviors in the alveolar bone and periodontal ligament. This review summarizes the current knowledge on the molecular mechanisms underlying accelerated orthodontic tooth movement, and the clinical and experimental methods that accelerate orthodontic tooth movement with possible molecular mechanisms. The review also shows directions for future studies to develop more clinically applicable methods to accelerate orthodontic tooth movement. PMID:25439213

  10. SAVE THE IRREMEDIABLE TOOTH WITH AID OF HYDROXYAPAT ITE

    Directory of Open Access Journals (Sweden)

    Golmoradizadeh

    2013-02-01

    Full Text Available ABSTRACT: Nowadays saving the irremediable tooth under the old method has low risk success, or in some cases it is impossible. This stu dy suggests a method that could predict a good prognosis after the operation. This case was, a crownless upper righ t 2 nd premolar with a big periapical lesion that extended the periradicular area also, with initial pa latal root resorption . Upon examination Chronic Preapical Periodontitis diagnosed. After RC T, the tooth was extracted, curetting and irrigation of the socket was done, fill ¼ of the so cket with hydroxyapatite and reimplant the tooth, during the reimplantation adjustment of the crown to root ratio considered as well ,then was splinted to the adjacent teeth for two weeks, A ntibiotic was prescribed to the patient for 7 days. Radiographic examination after two y ears shows that no more lesions are seen in the periapical and periradicular area, there was no mobil ity, and root resorption was aborted, and the tooth was in healthy condition.

  11. Fluoridation and tooth wear in Irish adults.

    LENUS (Irish Health Repository)

    Burke, F M

    2010-10-01

    The aim of this study was to determine the prevalence of tooth wear in adults in Ireland and its relationship with water fluoridation. The National Survey of Adult Oral Health was conducted in 2000\\/2001. Tooth wear was determined using a partial mouth examination assessing the upper and lower anterior teeth. A total of 2456 subjects were examined. In this survey, increasing levels and severity of tooth wear were associated with ageing. Men were more affected by tooth wear and were more likely to be affected by severe tooth wear than women. It was found that age, and gender were significant predictors of tooth wear (P < 0.01). Overall, there was no significant relationship between fluoridation and tooth wear in this study.

  12. Proteomic Analysis of Human Tooth Pulp: Proteomics of Human Tooth.

    Czech Academy of Sciences Publication Activity Database

    Eckhardt, Adam; Jágr, Michal; Pataridis, Statis; Mikšík, Ivan

    2014-01-01

    Ro?. 40, ?. 12 (2014), s. 1961-1966. ISSN 0099-2399 R&D Projects: GA ?R(CZ) GA13-17224S; GA ?R(CZ) GAP206/12/0453; GA MZd(CZ) NT14324 Institutional support: RVO:67985823 Keywords : dentin * human pulp * tandem mass spectrometry * tooth proteome * 2-dimensional gel electrophoresis Subject RIV: FF - HEENT, Dentistry Impact factor: 3.375, year: 2014

  13. Influence of Conventional and Digital Wax-ups on Axial Tooth Contour.

    Science.gov (United States)

    Abduo, Jaafar; Bennamoun, Mohammed; Tennant, Marc

    2015-01-01

    The aim of this study was to evaluate the impact of conventional and digital diagnostic wax-up on the axial tooth contour. Dental models of 15 patients were collected. Each model received conventional wax-up and digital wax-up. The conventional wax-up was based on tooth modification with dental wax on actual models. The digital wax-up involved fitting an average tooth form on virtual pretreatment models. Each wax-up model was digitally superimposed on the corresponding pretreatment model. For each modified tooth, analysis planes were extracted at three locations: mesial line angle, midtooth, and distal line angle. The impact of the following variables was evaluated: interarch location (maxilla vs mandible), intra-arch location (anterior vs posterior), tooth category (incisors, canines, premolars, and molars), and tooth location (midtooth vs line angle). The axial contour of the modified teeth increased after each wax-up, and this increase was directly proportional to the distance from the gingival margin. There is a clear tendency for the digital wax-up to cause a greater contour increase than the conventional wax-up. The anterior teeth were associated with a greater tooth contour increase than posterior teeth and the contour of the molars was the least affected. Although the conventional wax-up contour alteration was significantly less than for the digital wax-up, the actual difference was minimal. PMID:26133148

  14. Charcot-Marie-Tooth disease.

    LENUS (Irish Health Repository)

    Reilly, Mary M

    2011-03-01

    Charcot-Marie-Tooth (CMT) disease is the commonest inherited neuromuscular disorder affecting at least 1 in 2,500. Over the last two decades, there have been rapid advances in understanding the molecular basis for many forms of CMT with more than 30 causative genes now described. This has made obtaining an accurate genetic diagnosis possible but at times challenging for clinicians. This review aims to provide a simple, pragmatic approach to diagnosing CMT from a clinician\\'s perspective.

  15. [Research advances in tooth agenesis].

    Science.gov (United States)

    Feng, Hai-lan; Zhang, Xiao-xia; Wu, Hua

    2007-02-18

    Tooth agenesis constitutes one of the most common developmental anomalies in man. Oligodontia is defined as congenital absence of six or more teeth. Based on the studies of our team in cooperation with Peking University Center for Human Disease Genomics in the past five years, this article reviews the current research progress in clinical phenotypes and case collection, epidemiological investigation and etiological genetic studies of oligodontia. The symptoms of oligodontia were classified into syndromic and non-syndromic according to the occurrence of tooth agenesis with or without systemic developmental defects. As for the advancement of theories and techniques of molecular genetics, a number of gene mutations have been identified to be the direct etiological factors causing some specified diseases, especially those with developmental defects. Here, this article summarized the outcomes of molecular genetic study of some cases we collected. Of the systemic oligondontia patients, a new four-base-deletion mutation in PITX2 was identified in a large kindred with typical symptoms of Rieger Syndrome; four different gene mutations in ED1 casing X-linked hypohidrotic ectodermal displasia were found in five nucleus families. Compared with the former, non-syndromic oligodontia has more genetic heterogeneity rather than some specific virulence gene. PAX9 and MSX1 are the identified genes associated with family tooth agenesis without systemic syndrome. Also, in our research, three gene mutations in CBFA1 were detected in four cleidocranial dysplasia families, which is a systemic developmental disease including the symptoms of tooth eruption abnormality and accessory teeth. PMID:17304318

  16. Mechanism of human tooth eruption

    DEFF Research Database (Denmark)

    Kjær, Inger

    2014-01-01

    Human eruption is a unique developmental process in the organism. The aetiology or the mechanism behind eruption has never been fully understood and the scientific literature in the field is extremely sparse. Human and animal tissues provide different possibilities for eruption analyses, briefly discussed in the introduction. Human studies, mainly clinical and radiological, have focused on normal eruption and gender differences. Why a tooth begins eruption and what enables it to move eruptively ...

  17. Prosthetic clone and natural human tooth comparison by speckle interferometry

    Science.gov (United States)

    Slangen, Pierre; Corn, Stephane; Fages, Michel; Raynal, Jacques; Cuisinier, Frederic J. G.

    2010-09-01

    New trends in dental prosthodontic interventions tend to preserve the maximum of "body" structure. With the evolution of CAD-CAM techniques, it is now possible to measure "in mouth" the remaining dental tissues. The prosthetic crown is then designed using this shape on which it will be glued on, and also by taking into account the contact surface of the opposite jaw tooth. Several theories discuss on the glue thickness and formulation, but also on the way to evolve to a more biocompatible crown and also new biomechanical concepts. In order to validate these new concepts and materials, and to study the mechanical properties and mechanical integrity of the prosthesis, high resolution optical measurements of the deformations of the glue and the crown are needed. Samples are two intact premolars extracted for orthodontics reasons. The reference sample has no modifications on the tooth while the second sample tooth is shaped to receive a feldspathic ceramic monoblock crown which will be glued. This crown was manufactured with a chairside CAD-CAM system from an intra-oral optical print. The software allows to realize a nearly perfect clone of the reference sample. The necessary space for the glue is also entered with ideal values. This duplication process yields to obtain two samples with identical anatomy for further processing. The glue joint thickness can also be modified if required. The purpose is to compare the behaviour of a natural tooth and its prosthetic clone manufactured with "biomechanical" concepts. Vertical cut samples have been used to deal with planar object observation, and also to look "inside" the tooth. We have developed a complete apparatus enabling the study of the compressive mechanical behaviour of the concerned tooth by speckle interferometry. Because in plane displacements are of great interest for orthodontic measurements1, an optical fiber in-plane sensitive interferometer has been designed. The fibers are wrapped around piezoelectric transducers to perform "4-buckets" phase shifting leading to phase variations during the compression test. In-plane displacement fields from speckle interferometry already showed very interesting data concerning the mechanical behaviour of teeth: the dentine-enamel junction (DEJ) and the glue junction have been shown including their interfacing function. Mechanical action of the tooth surrounding medium will also be discussed.

  18. Restoration of the maxillary anterior tooth using immediate implantation with simultaneous ridge augmentation

    OpenAIRE

    Park Jun-Beom

    2010-01-01

    Atrophy is most severe during the first month of post-extraction in the anterior maxilla with the degree of horizontal bone resorption being nearly twice as high as that of vertical bone resorption. The loss of the buccal alveolar plate following tooth extraction may lead to palatal implant positioning of the implants. Thus, immediate or early implant placement in the extraction socket has been suggested, because it would reduce the time period and the number of surgical intervention and yiel...

  19. On gear tooth stiffness evaluation

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Jørgensen, Martin Felix

    2014-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an ...

  20. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... is Oral Health Important for Men? Pacifiers Have Negative and Positive Effects Is My Child at Risk for Early Childhood Tooth Decay? Headaches and Jaw Pain? Check Your Posture! Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral ...

  1. Investigation of EPR signals on tooth enamel

    International Nuclear Information System (INIS)

    Calcified tissues are involved in continues metabolic process in human organism exchanging a number of chemical elements with environment. The rate of biochemical reactions is tissue dependent and the slowest one at the tooth enamel, the most mineralized tissue of human organism. The long time stability and unique chemical composition make tooth enamel suitable for number of application. The assessment of individual radiation dose by Electron Paramagnetic Resonance (EPR) and evaluations of elemental composition by Instrumentation Neutron Activation Analysis (INAA) are the well known procedures where properties of tooth enamel intensively used. The current work is focused on investigation of EPR signals and determination of chemical composition on several teeth samples having different origin. The EPR spectra and INAA element content of milk tooth, caries tooth, and paradantose tooth have been compared to each other. The results showed that the intensity of EPR signal is much higher for the caries tooth than the for paradantose tooth that is in agreement with depleted Ca content

  2. Investigation of EPR signals on tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Pavlenko, A; Mironova-Ulmane, N; Polakov, M; Riekstina, D [Institute of Solid State Physics, University of Latvia, Riga (Latvia)

    2007-12-15

    Calcified tissues are involved in continues metabolic process in human organism exchanging a number of chemical elements with environment. The rate of biochemical reactions is tissue dependent and the slowest one at the tooth enamel, the most mineralized tissue of human organism. The long time stability and unique chemical composition make tooth enamel suitable for number of application. The assessment of individual radiation dose by Electron Paramagnetic Resonance (EPR) and evaluations of elemental composition by Instrumentation Neutron Activation Analysis (INAA) are the well known procedures where properties of tooth enamel intensively used. The current work is focused on investigation of EPR signals and determination of chemical composition on several teeth samples having different origin. The EPR spectra and INAA element content of milk tooth, caries tooth, and paradantose tooth have been compared to each other. The results showed that the intensity of EPR signal is much higher for the caries tooth than the for paradantose tooth that is in agreement with depleted Ca content.

  3. Addressing Tooth Decay in Head Start Children

    Science.gov (United States)

    Knowlden, Adam P.; Hill, Lawrence F.; Alles-White, Monica L.; Cottrell, Randall R.

    2012-01-01

    Tooth decay is the most prevalent chronic disease of childhood. Oral health education and dental services are crucial to reducing the number of children afflicted with dental cavities. Due to limited access to preventative care, Head Start children are particularly vulnerable to tooth decay. This article outlines practical implications of a…

  4. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Saturday, November 14, 2015 About | Contact InfoBites Quick Reference ... Learn more Halitosis (Bad Breath) How Do I Care for My Child's Baby Teeth? Is My Child at Risk for Early Childhood Tooth Decay? What is Baby Bottle Tooth ...

  5. USE THE REIMPLANTED TOOTH AS ABUTMENT FOR FIXED PAR TIAL DENTURE

    Directory of Open Access Journals (Sweden)

    Golmoradizadeh

    2013-04-01

    Full Text Available ABSTRACT: OBJECTIVE: Use of the fixed partial denture is more favorable t han the removable partial denture for my patient, she complained about e dentulism in upper right side and a little discomfort with second upper premolar. Clinical examin ation shows the tooth was crown less and radio graphically tooth had a big periapical lesi on with poor prognosis. METHOD: After root canal treatment and extraction the tooth, clea n and irrigate the socket, we are implanted it with hydroxyapatite again and follow the patient for six months. After six months, radio graph shows that the tooth was in ideal condition without mobility, then the tooth has used as an abutment for fixed partial denture with canine and 2 nd molar in order to have a better prognosis we used semi precision attachment, and foll ow her for three years. RESULT: Three years follow the patient shows the tooth is in an ac ceptable condition radio-graphically without mobility and patient was comfortable esthetically a nd functionally. CONCLUSION: In my opinion in this case use of the hydroxyapatite, crown lengthening during the re- implantation and use the semi precision attachment was the reaso n of increase the prognosis after treatment

  6. A Radiographic method for determining the actual tooth length

    Energy Technology Data Exchange (ETDEWEB)

    Nah, Kyung Soo; Cho, Bong Hae [Dept. of Oral Radiology, College of Dentistry, Pusan National University, Pusan (Korea, Republic of)

    1995-08-15

    Tooth length determination is a crucial step in endodontic treatment. Traditionally, radiographs are used to confirm working length of the root length. This study was performed to evaluate the radiographic distortion (magnification) and calculate correction coefficients for the object-film distance. Ninety-six radiographs were made of eight extracted teeth (two upper first premolars, two lower first premolars, two upper first molars, and two lower first molars) by using the 16 inch long cone paralleling techniques with 1 mm interval from 5 to 16 mm tooth-film distance. The following results obtained; 1. The least mean radiographic distortion from 5 to 16 mm tooth-film distance was 2.42 {+-}0.68% (the length of mesiobuccal cusp-mesial root of lower first molars), the greatest distortion was 4.74 {+-}1.36% (the length of mesiobuccal cusp-mesiobuccal root of upper first molars). 2. The greatest correction coefficient was 0.986 (the mesiobuccal cusp-mesial root of lower molars, the lowest one was 0.937 (the mesiobuccal cusp-mesiobuccal root of upper first molars).

  7. Possibilities of ESR-spectroscopy of the tooth enamel for in vivo determination of the radiation dose

    International Nuclear Information System (INIS)

    A review of recent publications on the topic is presented. The characteristics of the tooth as an in vivo dosemeter for the assessment of the individual cumulated dose are analysed. The correlation between the intensity of ESR-signal and the dose as well as the distinguishing of the signal caused by the native crystal structure of the tooth enamel and the one induced during the previous X-ray diagnostic procedures is discussed. The possibilities for in vivo measurement (without preliminary extraction of the tooth) is also reported. 4 figs., 44 refs

  8. Saw-toothed fish bone ingestion: A method for propulsion

    Scientific Electronic Library Online (English)

    Emily, Broadis; Wakisa, Mulwafu.

    2010-05-01

    Full Text Available We describe the case of an 11-year-old girl who presented with a lump in her neck. On exploration a 4 cm saw-toothed fish bone was extracted from the soft tissue of the anterior triangle of the neck. Ingested fish bones are a common presentation in accident and emergency departments, but there are o [...] nly a small number of reports of migration through the pharynx into soft tissues. Rare complications can include oesophageal perforation, haematoma formation, retropharyngeal abscesses and recurrent infections. To the best of our knowledge this is the first reported case of migration of an ingested fish bone in Malawi.

  9. Restoration of the maxillary anterior tooth using immediate implantation with simultaneous ridge augmentation

    Directory of Open Access Journals (Sweden)

    Park Jun-Beom

    2010-01-01

    Full Text Available Atrophy is most severe during the first month of post-extraction in the anterior maxilla with the degree of horizontal bone resorption being nearly twice as high as that of vertical bone resorption. The loss of the buccal alveolar plate following tooth extraction may lead to palatal implant positioning of the implants. Thus, immediate or early implant placement in the extraction socket has been suggested, because it would reduce the time period and the number of surgical intervention and yield higher patient satisfaction compared with delayed placed implants. However, placement of an implant immediately after tooth extraction may result in a gap between the occlusal portion of the implant and the surrounding alveolar bone crest. In this case report, an implant-supported restoration which is in harmony with the surrounding hard and soft tissue was created by the immediate implant placement with ridge augmentation in anterior region with high satisfaction from the patient.

  10. Tooth fractures in canine clinical practice

    International Nuclear Information System (INIS)

    Tooth fractures constitute a considerable fraction of all tooth diseases. Out of the 5,370 dogs treated during four years, 492 were presented with dental problems and 28.3 % of the latter were treated for tooth fractures. Canines were the most frequently affected teeth (38.8 %), followed by premolars (33.1 %), incisors (25.9 %), and molars (2.2 %), 55.4 % of the patients with canine and incisor fractures being large breed dogs. Fractures of premolars (mostly of 108, 208) were divided evenly irrespective of breed or body size. Nonsurgical endodontic treatment yielded good therapeutic results in most cases, but repeated treatment was necessary in some patients

  11. Assessment of proprioceptive allodynia after tooth-clenching exercises

    DEFF Research Database (Denmark)

    Dawson, Andreas; List, Thomas; Ernberg, Malin; Svensson, Peter

    2012-01-01

    To (A) evaluate test-retest reliability of vibrotactile sensitivity in the masseter muscle and (B) test if (1) the vibration threshold is decreased after experimental tooth clenching, (2) intense vibrations exacerbate pain after tooth clenching, (3) pain and fatigue are increased after tooth clenching, and (4) pressure pain thresholds are decreased after tooth clenching.

  12. External resorption presenting as an intracoronal radiolucent lesion in a pre-eruptive tooth.

    LENUS (Irish Health Repository)

    McNamara, C M

    1997-09-01

    A large intracoronal radiolucent lesion in an unerupted permanent molar was found during the routine assessment of a young male Caucasian prior to orthodontic treatment. The tooth was extracted. Histological examination indicated the lesion was caused by external resorption. The defect extended widely into the enamel and dentine, and was repaired in part by bone. The pulp chamber was not involved. The aetiology of these lesions is often obscure but in this case it appeared to have originated in the floor of two developmental pits on the occlusal surface of the tooth.

  13. Dose estimation by ESR on tooth enamel from two workers exposed to radiation due to the JCO accident

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR) dosimetry is useful to estimate the external dose for the general population as well as for occupational workers in a nuclear emergency. Three teeth were extracted from two exposed workers (A and B) related to the JCO criticality accident. Tooth enamel was carefully separated from other tooth parts and subjected to ESR dosimetry. Doses equivalent to the ?-ray dose of 60Co were estimated as follows: for worker A, the buccal and lingual sides of the eighth tooth in the upper right side, 11.8±3.6 and 12.0±3.6 Gy, respectively; for worker B, the buccal and lingual sides of the fourth tooth in the upper right side and the fifth tooth in the upper left side, 11.3±3.4 and 10.8±3.3 Gy, 11.7±3.5 and 11.4±3.4 Gy, respectively. The estimated doses were found to be similar and not dependent on the tooth positions, whether the buccal or lingual sides in each tooth. (author)

  14. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health The History of Dental Advances What is Orofacial ... is Baby Bottle Tooth Decay? Why is Oral Health Important for Men? When Should My Child First ...

  15. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... is Oral Health Important for Men? Pacifiers Have Negative and Positive Effects Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral ...

  16. Charcot-Marie-Tooth and Related Diseases

    Science.gov (United States)

    ... performance boost, each one is surrounded by a coating called myelin. Similar to the way plastic coat- ... myasthenic syndromes Diseases of Peripheral Nerve Charcot-Marie-Tooth disease Friedreich’s ataxia Dejerine-Sottas disease 13 CMT • © ...

  17. ATTITUDE AND KNOWLEDGE TOWARDS TOOTH AVULSION AMONG SPORTS TEACHERS

    OpenAIRE

    FARHEEN USTAD; MOHD INAYATULLAH KHAN; PRIYAYANKA BHUSHAN; FAREEDI MUKRAM ALI

    2013-01-01

    Background: Tooth avulsion is one of the commonest types of physical sport injury. Themanagement of these cases is critical in order to prevent complete loss of tooth and its subsequentconsequences. The prognosis of such avulsed tooth depends on prompt treatment. The emergencymanagement of such avulsed tooth is made by the sports teacher who is present at the sports ground. Thefirst–aid knowledge about tooth avulsion is must for the sports teacher. Aim: The objective of the presentstudy was t...

  18. In Vitro Spectrophotometry of Tooth Discoloration Induced by Tooth-Colored Mineral Trioxide Aggregate and Calcium-Enriched Mixture Cement

    Science.gov (United States)

    Arman, Marjan; Khalilak, Zohreh; Rajabi, Moones; Esnaashari, Ehsan; Saati, Keyvan

    2015-01-01

    Introduction: There are numerous factors that can lead to tooth discoloration after endodontic treatment, such as penetration of endodontic materials into the dentinal tubules during root canal treatment. The aim of this in vitro study was to compare discoloration induced by tooth colored mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement in extracted human teeth. Methods and Materials: Thirty two dentin-enamel cuboid blocks (7×7×2 mm) were prepared from extracted maxillary central incisors. Standardized cavities were prepared in the middle of each cube, leaving 1 mm of enamel and dentin on the labial surface. The specimens were randomly divided into two study groups (n=12) and two positive and negative control groups (n=4). In either study groups the cavities were filled with MTA or CEM cement. The positive and negative control groups were filled with blood or left empty, respectively. The cavities were sealed with composite resin and stored in normal saline. Color measurement was carried out by spectrophotometry at different time intervals including before (T0), and 1 week (T1), 1 month (T2) and 6 months (T3) after placement of materials. Repeated-measures ANOVA was used to compare the discoloration between the groups; the material type was considered as the inter-subject factor. The level of significance was set at 0.05. Results: No significant differences were detected between the groups in all time intervals (P>0.05). Conclusion: Tooth discoloration was similarly detectable with both of the two experimental materials.

  19. Gene Expression Profiling during Murine Tooth Development

    OpenAIRE

    Landin, Maria A. dos Santos Silva; Shabestari, Maziar; Babaie, Eshrat; Reseland, Janne E; Osmundsen, Harald

    2012-01-01

    The aim of this study was to describe the expression of genes, including ameloblastin (Ambn), amelogenin X chromosome (Amelx), and enamelin (Enam) during early (pre-secretory) tooth development. The expression of these genes has predominantly been studied at post-secretory stages. Deoxyoligonucleotide microarrays were used to study gene expression during development of the murine first molar tooth germ at 24?h intervals, starting at the 11th embryonic day (E11.5), and up to the 7th day after ...

  20. Ultrasonographic Detection of Tooth Flaws

    Science.gov (United States)

    Bertoncini, C. A.; Hinders, M. K.; Ghorayeb, S. R.

    2010-02-01

    The goal of our work is to adapt pulse-echo ultrasound into a high resolution imaging modality for early detection of oral diseases and for monitoring treatment outcome. In this talk we discuss our preliminary results in the detection of: demineralization of the enamel and dentin, demineralization or caries under and around existing restorations, caries on occlusal and interproximal surfaces, cracks of enamel and dentin, calculus, and periapical lesions. In vitro immersion tank experiments are compared to results from a handpiece which uses a compliant delay line to couple the ultrasound to the tooth surface. Because the waveform echoes are complex, and in order to make clinical interpretation of ultrasonic waveform data in real time, it is necessary to automatically interpret the signals. We apply the dynamic wavelet fingerprint algorithms to identify and delineate echographic features that correspond to the flaws of interest in teeth. The resulting features show a clear distinction between flawed and unflawed waveforms collected with an ultrasonic handpiece on both phantom and human cadaver teeth.

  1. Gamma-ray dose response of ESR signals in tooth enamel of cows and mice in comparison with human teeth

    International Nuclear Information System (INIS)

    The ESR dose responses of the tooth enamel samples prepared from teeth of cow and mice were examined in comparison with that of human. The samples were prepared with combined procedures of mechanical and chemical treatments of teeth. The ESR dose response was extracted from the total ESR spectra of tooth enamel samples by a specially developed matrix method. The dosimetric signal was found to be increased linearly with gamma dose for all studied tooth enamel samples. The radiation sensitivity of cow tooth enamel was found to be close to that of human teeth while that of mouse teeth was about 25% lower. The present results indicate that, having high radiation sensitivity, cow and mouse teeth can be used for retrospective radiation dosimetry in low-dose level

  2. Efficacy of various materials in recording enamel rod endings on tooth surface for personal identification

    Directory of Open Access Journals (Sweden)

    K Manjunath

    2011-01-01

    Full Text Available Aim: To analyze efficacy of cellulose acetate film, cellophane tape, and light body impression material in recording enamel rod endings on tooth surface for personal identification. Materials and Methods: Surface enamel rod endings of 30 extracted teeth were recorded from the same area of the same tooth for two times using cellulose acetate film, cellophane tape, and light body impression material. Photomicrographs of enamel rod endings were taken and subjected to Verifinger standard SDK version 5.0 software for analysis. Minutiae scores of all enamel rod end patterns obtained using these three imprint materials were statistically analyzed. Results: Cellulose acetate film imprint showed complete enamel rod end patterns and the software was able to identify the particular tooth with the same previous identification number in subsequent recordings as well. Cellophane tape and light body rubber-base impression material imprint showed incomplete enamel rod end patterns and the software failed to identify the particular tooth with the same previous identification number in subsequent recordings. Statistical analysis revealed that cellulose acetate film recorded more number of minutiae points compared with the other imprint materials. Conclusion: Cellulose acetate film is a reliable material for recording enamel rod endings on tooth surface for personal identification compared with cellophane tape and light body rubber-base impression material.

  3. Preimplantation filling of tooth socket with ?-tricalcium phosphate/polylactic-polyglycolic acid (?-TCP/PLGA root analogue: clinical and histological analysis in a patient

    Directory of Open Access Journals (Sweden)

    Kokovi? Vladimir

    2011-01-01

    Full Text Available Introduction. Bone resorption is a physiological process after tooth extraction. The use of bone substitutes to fill the tooth socket is suggested to prevent bone resorption and establish good bone architecture for implant placement. A pure ß-tricalcium phosphate coated with copolymer (polylactic-polyglycolic acid as a root analogue, is suitable for filling tooth sockets. Case report. We presented a patient successfully treated with root analogue after extraction of the right second lower premolar. Three months later, the patient was planned for the placement of six TE® ITI dental implants into the mandible. During the surgery, the biopsy of bone-like tissue from the previously treated socket was taken. All the implants were immediately loaded due to good primary stability. Histological analysis of the specimen revealed fibrous healing in the area treated with root analogue. Conclusion. The use of ß-tricalcium phosphate coated with copolymers after tooth extraction enables satisfactory bone architecture for consequent implant treatment.

  4. Adhesion of Dental Materials to Tooth Structure

    Science.gov (United States)

    Mitra, Sumita B.

    2000-03-01

    The understanding and proper application of the principles of adhesion has brought forth a new paradigm in the realm of esthetic dentistry. Modern restorative tooth procedures can now conserve the remaining tooth-structure and also provide for the strengthening of the tooth. Adhesive restorative techniques call for the application and curing of the dental adhesive at the interface between the tooth tissue and the filling material. Hence the success of the restoration depends largely on the integrity of this interface. The mechanism of adhesion of the bonding materials to the dental hard tissue will be discussed in this paper. There are four main steps that occur during the application of the dental adhesive to the oral hard tissues: 1) The first step is the creation of a microstructure in the tooth enamel or dentin by means of an acidic material. This can be through the application of a separate etchant or can be accomplished in situ by the adhesive/primer. This agent has to be effective in removing or modifying the proteinaceous “smear” layer, which would otherwise act as a weak boundary layer on the surface to be bonded. 2) The primer/adhesive must then be able to wet and penetrate the microstructure created in the tooth. Since the surface energies of etched enamel and that of etched dentin are different finding one material to prime both types of dental tissues can be quite challenging. 3) The ionomer types of materials, particularly those that are carboxylate ion-containing, can chemically bond with the calcium ions of the hydroxyapatite mineral. 4) Polymerization in situ allows for micromechanical interlocking of the adhesive. The importance of having the right mechanical properties of the cured adhesive layer and its role in absorbing and dissipating stresses encountered by a restored tooth will also be discussed.

  5. Efeito comparativo entre a dipirona sódica e a dipirona sódica associada à cafeína no controle da dor pós-exodontia / Comparative effect of sodium dipyrone and sodium dipyrone associated to caffeine to control post-tooth extraction pain

    Scientific Electronic Library Online (English)

    Carllini Barroso, Vicentini; Juliana Cama, Ramacciato; Rubens Gonçalves, Teixeira; Francisco Carlos, Groppo; Rogério Heládio Lopes, Motta.

    2013-09-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: O adequado controle da dor pós-operatória constitui um desafio entre as especialidades cirúrgicas, a despeito dos recentes avanços das técnicas de analgesia e dos analgésicos. A cafeína tem sido utilizada como adjuvante terapêutico para potencializar a eficácia analgésica [...] de alguns fármacos, porém ainda não existe relatos de investigação científica da associação com a dipirona sódica em dor pós-operatória em procedimentos odontológicos. Dessa forma, o objetivo deste estudo foi observar e comparar a eficácia da dipirona sódica isolada e da dipirona sódica associada à cafeína no controle da dor pós-operatória em cirurgia dental, considerando os parâmetros hemodinâmicos dos pacientes como indicador de ansiedade e de dor durante a cirurgia. MÉTODOS: Estudo cruzado e duplo encoberto incluiu 50 pacientes jovens e saudáveis (25 homens e 25 mulheres) com indicação de exodontia bilateral de terceiros molares mandibulares impactados. O lado operado, o gênero do paciente e o fármaco analgésico usado foram randomizados. Os escores obtidos pela escala analógica visual foram submetidos ao teste de Friedman (? = 0,05) para comparação das intensidades dolorosas em intervalos definidos (pré-operatório, pós-operatório imediato, 1, 2, 4 12 horas, 1, 2, 3 e 7 dias após as cirurgias) e as alterações nos parâmetros de pressão arterial e frequên­cia cardíaca foram mensurados no pré-operatório, após a injeção anestésica e no pós-operatório (teste de Friedman, ? = 0,05). RESULTADOS: Os pacientes experimentaram dor leve nos dois primeiros dias de pós-operatório e não houve diferença estatisticamente significante entre a eficácia analgésica da dipirona sódica isolada e da dipirona sódica associada à cafeína nos diferentes intervalos medidos. A maioria das alterações cardiovasculares observadas estava dentro da normalidade, considerando a ansiedade e estresse induzido pela cirurgia. CONCLUSÃO: O protocolo terapêutico proposto neste estudo não demonstrou diferença estatística significante na eficiência analgésica da dipirona sódica associada ou não a cafeína no controle da dor pós-exodontia. Abstract in english BACKGROUND AND OBJECTIVES: Adequate postoperative pain control is a challenge among surgical specialties, in spite of recent advances in analgesic techniques and analgesics. Caffeine has been used as therapeutic adjuvant to potentiate analgesic efficacy of some drugs, however there are still no scie [...] ntific investigation reports on the association with sodium dipyrone in the postoperative period of dental procedures. So, this study aimed at observing and comparing the efficacy of sodium dipyrone alone or in association with caffeine to control postoperative pain of dental procedures, considering hemodynamic parameters of patients as indicators of anxiety and pain during surgery. METHODS: This is a crossover and double-blind study involving 50 young and healthy patients (25 males and 25 females) referred for bilateral extraction of impacted mandibular third molars. Operated side, patient's gender and analgesic drug used were randomized. Visual analog scale scores were submitted to Friedman test (? = 0.05) to compare pain intensity at defined intervals (preoperative, immediate postoperative, 1, 2, 4 and 12 hours, 1, 2, 3 and 7 days after surgery). Blood pressure and heart rate were measured in the preoperative period, after anesthetic injection and in the postoperative period (Friedman test, (? = 0.05). RESULTS: Patients have referred mild pain in the first two postoperative days and there has been no statistically significant difference between the analgesic efficacy of sodium dipyrone alone or in association with caffeine in different evaluated intervals. Most cardiovascular changes were within normality, considering anxiety and stress induced by surgery. CONCLUSION: The therapeutic protocol proposed in this study has not shown statistically significant difference between sodium dipyrone associated

  6. Hydroxyapatite coating on damaged tooth surfaces by immersion

    International Nuclear Information System (INIS)

    Hydroxyapatite (HAp) was coated on scratched areas of a human tooth and HAp disks by the immersion method in a HAp colloidal solution (?20 ?m of average diameter dispersed in DI water). The surface morphologies of the scratched area after immersion for 1-3 months were investigated showing that the damaged surfaces were remarkably recovered. Then, the mechanical property and chemical stability of the HAp coating layers on both specimens were determined via the Vickers hardness test and concentration measurement of extracted Ca2+ ions, respectively, after strong acidic treatment. The cellular behavior of mouse calvaria-derived pre-osteoblastic cells (MC3T3-E1) was also examined on the HAp layers regenerated on micro-scratched HAp disks for the purpose of their potential applications on maxillofacial bone conservation and reconstruction for prosthetic dentistry, and artificial disk preparation of a vertebral column. The notable loss of Ca2+ ions under a highly acidic condition was not observed in the layers coated by HAp adsorption, indicating that the coating surface was well adhered with the original surfaces of the respective specimen. Moreover, the HAp adsorption did not adversely affect the adhesion, growth and proliferation of MC3T3-E1 cells on the coated HAp layers for up to 21 days. These results suggest that the HAp coating on the scratched areas of the tooth would be effectively applicable for the development of long-term prevention of micro-cleavage and tooth health supporters to reduce discoloration and further maxillofacial and orthopedic applications.

  7. ESR dosimetry using human tooth enamel

    International Nuclear Information System (INIS)

    To estimate the individual cumulative dose of atomic bomb (A-bomb) survivors or radiologic technologists by measuring electron spin resonance (ESR) of teeth, some characteristics of tooth enamel as ESR dosimeter were studied. The ESR signal of CO33- was stable and increased linearly with exposed dose. The response of ESR signal, however, was changed with photon energy. This indicates that the exposed radiation quality must be considered in evaluating the absorbed dose. The merit of this method is that it permits direct estimation of the absorbed dose by measuring the intensity of ESR of tooth taken from exposed persons. (author)

  8. Tooth avulsions resulting from basketball net entanglement.

    Science.gov (United States)

    Kumamoto, D P; Winters, J; Novickas, D; Mesa, K

    1997-09-01

    The authors conducted a survey of dentists reporting tooth avulsions from basketball net accidents. Although the number of people injured was small, the dental injuries were serious. In many cases, multiple teeth were avulsed as a result of the maxillary anterior teeth becoming entangled in the basketball net while the patients were attempting to slamdunk a basketball either on a lowered backboard or from a raised take-off area. The authors present recommendations for preventing tooth avulsions resulting from basketball net entanglement. PMID:9297949

  9. Decision-making deficits associated with disrupted synchronization between basolateral amygdala and anterior cingulate cortex in rats after tooth loss.

    Science.gov (United States)

    Xu, Xiaoxiang; Cao, Bing; Wang, Jun; Yu, Tianran; Li, Ying

    2015-07-01

    Human studies have shown that multiple teeth loss was significantly associated with cognitive impairment, dementia and Alzheimer's disease. However, the causal relationship between tooth loss and cognitive deficits has not been clarified. Rodents demonstrate human-like cognitive faculties. In this study by performing rat gambling task (RGT), we reported that prolonged tooth loss condition by extracting all left molars in the rats led to an increase in the proportion of poor decision-makers, and decrease in the proportion of good decision-makers compared with controls. No influence was detected on the general activity and motivation after tooth loss. Recent experiments have shown that decision-making performances in the RGT rely on the functional integrity of the amygdala and anterior cingulate cortex (ACC). The theta band brain oscillation has been acknowledged for extensive cognitive functions. Here, we performed multiple-electrode array recordings of local field potential (LFP) in anesthetized rats. The results exhibited an increase in accumulative power of the theta frequency of LFP in the basolateral amygdala (BLA) and decrease of theta power in the ACC in tooth loss rats. Furthermore, cross-correlation analysis displayed that tooth loss suppressed the synchronization of theta frequency of LFP between the BLA and ACC, indicating reduced neuronal communications between these two regions. In conclusion, we demonstrate for the first time that tooth loss leads to higher-order cognitive deficits accompanied by the alteration of theta frequency of LFP in brain circuitries and disruption of neural network integrity. PMID:25684327

  10. Causes of Charcot-Marie-Tooth Disease (CMT)

    Science.gov (United States)

    ... MDA clinic. Also, see Facts About Genetics and Neuromuscular Diseases . Disease: Charcot-Marie-Tooth Disease (CMT) Hereditary Motor ... Marie-Tooth & Related Diseases Facts About Genetics and Neuromuscular Diseases A Teacher's Guide to Neuromuscular Disease Learning to ...

  11. Genetics Home Reference: Charcot-Marie-Tooth disease

    Science.gov (United States)

    ... step (or gait) and increase the risk of ankle injuries and tripping. As the disease progresses, muscles in ... of Charcot-Marie-Tooth disease and may include treatment providers. Gene Review: Charcot-Marie-Tooth Hereditary Neuropathy ...

  12. Tooth-marked small theropod bone: an extremely rare trace

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2001-01-01

    Tooth-marked dinosaur bones provide insight into feeding behaviours and biting strategies of theropod dinosaurs. The majority of theropod tooth marks reported to date have been found on herbivorous dinosaur bones, although some tyrannosaurid bones with tooth marks have also been reported. In 1988 a partial skeleton of the dromaeosaurid Saurornitholestes was collected from southern Alberta, Canada, that bore marks on one dentary. The location and morphology of the tooth marks suggests that a ther...

  13. Patient Discomfort Following Single-Tooth Implant Placement

    DEFF Research Database (Denmark)

    Spin-Neto, Rubens; Pontes, Ana Emília Farias; Wenzel, Ann; Sakakura, Celso Eduardo

    2014-01-01

    Aims: Evaluate postoperative discomfort (pain, bleeding and swelling) in single-tooth implant patients submitted to immediate or conventional tooth restoration together with assessment of treatment time. Methods: Twenty-four patients who received single-tooth maxillary dental implants were randomly assigned to an IR (Immediate Restoration) or CR (Conventional Restoration) group. In IR, an implant was inserted and a provisional tooth crown was delivered within the same session, while in CR it was...

  14. A study on ESR dating characteristics of tooth enamel fossils

    International Nuclear Information System (INIS)

    The characteristics of ESR signals used in the dating of animal tooth enamel fossils have been investigated. According to the comparison of the results obtained from tooth enamel with those from pure substance and the study by positron annihilation technique, it can be concluded that the paramagnetic centers of tooth enamel is produced by PO43- ion formed F centers

  15. On the mechanical properties of tooth enamel under spherical indentation.

    Science.gov (United States)

    Chai, Herzl

    2014-11-01

    The mechanical properties of tooth enamel generally exhibit large variations, which reflect its structural and material complexity. Some key properties were evaluated under localized contact, simulating actual functioning conditions. Prominent cusps of extracted human molar teeth were polished down ~0.7 mm below the cusp tip and indented by tungsten carbide balls. The internal damage was assessed after unloading from longitudinal or transverse sections. The ultimate tensile stress (UTS) was determined using a novel bilayer specimen. The damage is characterized by penny-like radial cracks driven by hoop stresses and cylindrical cracks driven along protein-rich interrod materials by shear stresses. Shallow cone cracks typical of homogeneous materials which may cause rapid tooth wear under repeat contact are thus avoided. The mean stress vs. indentation strain curve is highly nonlinear, attributable to plastic shearing of protein between and within enamel rods. This curve is also affected by damage, especially radial cracks, the onset of which depends on ball radius. Several material properties were extracted from the tests, including shear strain at the onset of ring cracks ?(F) (=0.14), UTS (=119 MPa), toughness K(C) (=0.94 MPa m(1/2)), a crack propagation law and a constitutive response determined by trial and error with the aid of a finite-element analysis. These quantities, which are only slightly sensitive to anatomical location within the enamel region tested, facilitate a quantitative assessment of crown failure. Causes for variations in published UTS and K(C) values are discussed. PMID:25034644

  16. The Teamwork Approach to Esthetic Tooth Replacement with Immediate Implant Placement and Immediate Temporization.

    Science.gov (United States)

    Levin, Barry P; Wilk, Brian L

    2015-10-01

    Enduring a period of edentulism between extraction and final restoration is difficult for patients- especially when it concerns the esthetic zone. The approach described demonstrates key points of consideration when replacing a maxillary anterior tooth with a dental implant using immediate implant placement, hard- and soft-tissue augmentation, and provisionalization. The authors stress adherence to patient selection and prosthetic design guidelines, and recommend the use of a digital impression technique, rather than traditional, rubber-based impressions. PMID:26448151

  17. Biodosimetry: chromosome aberration in lymphocytes and electron paramagnetic resonance in tooth enamel from atomic bomb survivors

    International Nuclear Information System (INIS)

    One hundred enamel samples isolated from extracted teeth donated by atomic bomb survivors were subjected to free radical measurement by means of electron paramagnetic resonance (ESR). Results comparing ESR with the chromosome aberration frequency in lymphocytes of the tooth donors, and with the physically estimated DS86 dose suggested that ESR data correlated more closely with chromosome data than with the estimated DS86 doses, probably because DS86 may depend on erroneous memory in some cases. 9 refs, 4 figs

  18. Effect of Multiple Adhesive Coating on Microshear Bond Strength to Primary Tooth Dentin

    OpenAIRE

    Beheshteh Malekafzali Malekafzali; Amir Ghasemi; Hassan Torabzadeh; Reza Hamedani; Nekoo Tadayon

    2013-01-01

    Objective: Multiple adhesive coating is a controversial topic, especially in primary dentition that should be clarified. We evaluated the effect of multiple consecutive adhesive resin coatings on the microshear bond strength (µSBS) of composite resin to primary tooth dentin utilizing a filled (Adper Single Bond Plus) and an unfilled (Adper Single Bond) adhesive resin.Materials and Methods: Thirty extracted primary canines were randomly allocated into two groups based on the adhesive used. Den...

  19. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health Temporomandibular Joint Disorder What is Baby Bottle Tooth ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  20. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Tuesday, November 10, 2015 About | Contact InfoBites Quick Reference ... (Bad Breath) The History of Dental Advances How Do I Care for My Child's Baby Teeth? What is Baby Bottle Tooth Decay? What is a Composite Resin (White Filling)? Headaches and ...

  1. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Friday, January 08, 2016 About | Contact InfoBites Quick Reference ... Oral Health What is Baby Bottle Tooth Decay? What is Dental Amalgam (Silver Filling)? Temporomandibular Joint Disorder How Do I Care for My Child's Baby Teeth? What is a ...

  2. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health What is Baby Bottle Tooth Decay? What is ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  3. Recent Approaches in Tooth Engineering Research.

    Czech Academy of Sciences Publication Activity Database

    Švandová, Eva; Veselá, Barbora; K?ivánek, J.; Hampl, A.; Matalová, Eva

    2014-01-01

    Ro?. 60, Suppl 1 (2014), s. 21-29. ISSN 0015-5500 R&D Projects: GA ?R GAP304/11/1418; GA MZd(CZ) NT11420 Institutional support: RVO:67985904 Keywords : engineering * tooth * stem cells * culture techniques Subject RIV: EA - Cell Biology Impact factor: 1.000, year: 2014

  4. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Men's Oral Health How Do I Care for My Child's Baby Teeth? What is a Composite Resin (White Filling)? What is Baby Bottle Tooth Decay? The History of Dental Advances Headaches and Jaw ... | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  5. Death in the life of a tooth.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Tucker, A. S.; Sharpe, P. T.

    2004-01-01

    Ro?. 83, ?. 1 (2004), s. 11-16. ISSN 0022-0345 R&D Projects: GA ?R GP204/02/P112 Institutional research plan: CEZ:AV0Z5045916 Keywords : apoptosis * tooth development Subject RIV: EA - Cell Biology Impact factor: 3.131, year: 2004

  6. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Saturday, January 02, 2016 About | Contact InfoBites Quick Reference ... Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find ...

  7. Caspase-7 in molar tooth development.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Vanden Berghe, T.; Švandová, Eva; Vandenabeele, P.; Healy, C.; Sharpe, P. T.; Tucker, A. S.

    2012-01-01

    Ro?. 57, ?. 11 (2012), s. 1474-1481. ISSN 0003-9969 R&D Projects: GA AV ?R IAA600450904 Grant ostatní: GA ?R(CZ) GAP502/12/1285 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth * apoptosis * mineralisation Subject RIV: FF - HEENT, Dentistry Impact factor: 1.549, year: 2012

  8. EPR dosimetry with tooth enamel: A review

    Energy Technology Data Exchange (ETDEWEB)

    Fattibene, Paola, E-mail: paola.fattibene@iss.i [Istituto Superiore di Sanita, Department of Technology and Health, Viale Regina Elena 299, I-00161 Rome (Italy); Callens, Freddy, E-mail: freddy.callens@ugent.b [Ghent University, Department of Solid State Sciences, Krijgslaan 281-S1, B-9000 Gent (Belgium)

    2010-11-15

    When tooth enamel is exposed to ionizing radiation, radicals are formed, which can be detected using electron paramagnetic resonance (EPR) techniques. EPR dosimetry using tooth enamel is based on the (presumed) correlation between the intensity or amplitude of some of the radiation-induced signals with the dose absorbed in the enamel. In the present paper a critical review is given of this widely applied dosimetric method. The first part of the paper is fairly fundamental and deals with the main properties of tooth enamel and some of its model systems (e.g., synthetic apatites). Considerable attention is also paid to the numerous radiation-induced and native EPR signals and the radicals responsible for them. The relevant methods for EPR detection, identification and spectrum analyzing are reviewed from a general point of view. Finally, the needs for solid-state modelling and studies of the linearity of the dose response are investigated. The second part is devoted to the practical implementation of EPR dosimetry using enamel. It concerns specific problems of preparation of samples, their irradiation and spectrum acquisition. It also describes how the dosimetric signal intensity and dose can be retrieved from the EPR spectra. Special attention is paid to the energy dependence of the EPR response and to sources of uncertainties. Results of and problems encountered in international intercomparisons and epidemiological studies are also dealt with. In the final section the future of EPR dosimetry with tooth enamel is analyzed.

  9. Molecular basis of tooth germ development.

    Czech Academy of Sciences Publication Activity Database

    Fleischmannová, Jana; Krej?í, P.; Matalová, Eva; Míšek, Ivan

    2007-01-01

    Ro?. 16, ?. 4 (2007), s. 39-46. ISSN 1210-4272 R&D Projects: GA AV ?R KJB500450503; GA MŠk OC B23.001 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth germ development Subject RIV: FF - HEENT, Dentistry

  10. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Tuesday, October 06, 2015 About | Contact InfoBites Quick Reference ... Job? Start by Visiting the Dentist When Should My Child First See a Dentist? Is My Child at Risk for Early Childhood Tooth Decay? How Do I Care for My Child's Baby Teeth? Pacifiers Have Negative ...

  11. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Learn more Halitosis (Bad Breath) When Should My Child First See a Dentist? Men: Looking for a Better Job? Start by Visiting the Dentist What is Baby Bottle Tooth Decay? Why is Oral Health Important for Men? Pacifiers Have Negative and Positive Effects Learn what those dental words mean. The Life ...

  12. Epithelio-Mesenchymal Transformation During Tooth Development.

    Czech Academy of Sciences Publication Activity Database

    Štembírek, Jan; Buchtová, Marcela; Matalová, Eva; Stránský, J.; Míšek, Ivan

    Bruges : EACMFS, 2010. s. 198-198. [Congress of the European Association for Cranio-Maxillo- Facial Surgery /20./. 14.09.2010-17.09.2010, Bruges] Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth development Subject RIV: FF - HEENT, Dentistry

  13. Apoptotic cell elimination during early tooth development.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Míšek, Ivan; Chovancová, Eva

    2003-01-01

    Ro?. 72, ?. 7 (2003), s. 34. ISSN 0001-7213. [Congress of the European Association of Veterinary Anatomists/24./. 21.07.2002-25.07.2002, Brno] R&D Projects: GA ?R GP204/02/P112 Institutional research plan: CEZ:AV0Z5045916 Keywords : tooth development Subject RIV: FF - HEENT, Dentistry

  14. Tooth’s Tensions Analysis of Face Worm Gears with Cylindrical Pinion Development of FEA

    Directory of Open Access Journals (Sweden)

    Gavrila Ion

    2009-12-01

    Full Text Available Tooth’s tension in lapping process for worm face gear is proposed. The stress analysis of the gear drive is performed using a three-dimensional finite element analysis. The developed simulation is illustrated with numerical examples. This complex and intuitive simulation was created with CAD-CAM, MATH-CAD and FEM support. This simulation contain data collected from EU standards

  15. Is tooth wear in the primary dentition predictive of tooth wear in the permanent dentition? Report from a longitudinal study.

    LENUS (Irish Health Repository)

    Harding, M A

    2010-03-01

    To determine the prevalence of tooth wear in the permanent dentition of a sample of 12-year-old school children and establish whether an association exists between tooth wear recorded now and tooth wear recorded in their primary dentition at age five.

  16. Treatment of localized lesion of the tooth and surrounding tissue caused by dental disharmony: Case report

    Directory of Open Access Journals (Sweden)

    An?elkovi? Slobodan

    2010-01-01

    Full Text Available The loss of proper contact of the adjacent teeth, which usually occurs as a result of caries or tooth extraction, can lead to serious consequences on oral tissues health as well as on the function of complete oral system, unless timely repaired. It often happens that the irregular contact of the tooth due to inadequate filling remains unnoticed by the patient and dentist. Also, if the loss of contact caused by caries or after tooth extraction is not treated, it often leads to inclination of adjacent teeth and their traumatic contact in relation to the antagonists. If this situation remains for a long time, it can cause significant disorder for which rehabilitation, complex therapy and long period of time are required. The aim of this study was to point out the proper procedure for the treatment of complex lesions of teeth and adjacent tissues, caused by extraction of the second lower right premolar and impaired contact between the first molar and first premolar.

  17. [Biomechanical study on orthodontic tooth movement: changes in biomechanical property of the periodontal tissue in terms of tooth mobility].

    Science.gov (United States)

    Inoue, Y

    1989-12-01

    The magnitude of tooth mobility has been frequently used for evaluating biomechanical response of the periodontal tissue to applied forces. However, tooth mobility during orthodontic tooth movement has not been measured. The purpose of this study was to investigate changes in biomechanical property of the periodontal tissue during canine retraction, in terms of tooth mobility. The upper canines on both sides of ten orthodontic patients were moved in the distal direction for about four weeks with an initial force of 200 gf. An amount of tooth movement and a magnitude of tooth mobility were measured every 3 or 4 days during retraction. A distally directed force up to 500 gf was continuously applied to each canine and tooth mobility was measured with a noncontact type of eddy current displacement sensor. A two-dimensional finite element model was constructed and displacements of the finite element model were calculated with various Young's moduli in loading with a 100 gf force in the distal direction. In comparison with the magnitudes of the tooth mobility, Young's modulus of the periodontal membrane before retraction and the influence of the biomechanical factors on changes in tooth mobility were investigated. The tooth movement curve was divided into three phases; an initial phase, a lag phase and a post-lag phase. The magnitudes of tooth mobility at the initial phase were significantly larger than those before retraction within the range of 250 gf to 500 gf and these magnitudes decreased during the lag phase. The magnitudes of tooth mobility at the post-lag phase significantly increased, within the range of 50 gf to 500 gf, than those before retraction. As a result of curveliniar regression analysis, the tooth mobility curves approximated to delta = AFB, where delta and F denote tooth mobility and force respectively. The coefficients A and B changed according to the phases of tooth movement. An inclination of the tooth mobility curve expressed by a tangent at the 400 gf force was the largest at the initial phase, and this inclination at the 100 gf force was the largest at the post-lag phase. Young's modulus of the periodontal membrane before retraction was determined to be approximately 35 gf/mm2 and Young's modulus of the periodontal membrane was the most important factor on the increase of tooth mobility. Tooth mobility significantly varied associated with tooth movement. It was indicated that biomechanical property of the periodontal tissue changes in response to each phase of tooth movement. In particular, Young's modulus of the periodontal membrane decreased at the post-lag phase of the orthodontic tooth movement. PMID:2488921

  18. A TOOTH TATTOO WITH A PURPOSE: AN INNOVATIVE APPROACH

    Directory of Open Access Journals (Sweden)

    Neetu

    2014-01-01

    Full Text Available Skin is not the only place that can be decorated with a tattoo. You can decorate your tooth with amazing tattoos. Tooth tattoos and tooth jewels have become one of the hottest fashion trends , and a very popular arrival in cosmetic dentistry. But won’t it be a boon if it had some preventive or medicinal v alue. Yes tooth tattoos can act as indicators of once illness. These tiny electronic sensors can diagnose illnesses by 'tasting' your breath. This paper is an insight into how a tooth tattoos can pick up early warning signs of sickness or infection by bact eria in people's breath.

  19. Multidisciplinary Management of Complicated Crown-Root Fracture of an Anterior Tooth Undergoing Apexification

    Science.gov (United States)

    Mese, Merve; Akcay, Merve; Yasa, Bilal; Akcay, Huseyin

    2015-01-01

    The purpose of this case report was to present the multidisciplinary management of a subgingival crown-root fracture of a patient undergoing apexification treatment. A 12-year-old male patient was referred to the pediatric dentistry clinic with an extensive tooth fracture of the right permanent maxillary lateral incisor. Clinical and radiographic examinations revealed the presence of a complicated crown-root fracture, which had elongated to the buccal subgingival area. The dental history disclosed that the apexification procedure had been started to be performed after his first trauma experience and he had neglected his appointment. The coronal fragment was gently extracted; endodontic treatment was performed; flap surgery was performed to make the fracture line visible. The coronal fragment was reattached to the root fragment with a dual-cure luting composite. A fiber post was stabilized and the access cavity of the tooth was restored with composite resin. At the end of the 24th month, the tooth was asymptomatic, functionally, esthetically acceptable and had no periapical pathology. It is important for the patients undergoing apexification treatment to keep their appointments because of the fracture risk. Restoration of the fractured tooth by preparing retention grooves and a bonding fiber-reinforced post are effective and necessary approaches for successful management. PMID:26146573

  20. Study on electron spin resonance dosimetry of dog tooth enamel

    International Nuclear Information System (INIS)

    Four groups dog tooth enamel samples were irradiated with different dose by 137Cs ?-rays. Their electron spin resonance (ESR) spectra pre- and post-irradiated were measured and the changes of ESR signal intensities were analyzed. The results showed that the average intensity of native signals of dog tooth samples was 20.8±2.9, much weaker than that of human 39.5; the dosimetric signal intensities of dog tooth enamel increased with the absorbed doses; the mass of each sample is 100 mg. The average irradiation response of dog tooth enamel samples was (37.1±2.1) Gy-1, very close to that of human tooth samples (36.3 Gy-1). The dog tooth can be used for retrospective dosimetry when human tooth are difficult to collect. (authors)

  1. Retrospective biodosimetry with small tooth enamel samples using K-Band and X-Band

    International Nuclear Information System (INIS)

    In an attempt to make the in vitro electron spin resonance (ESR) retrospective dosimetry of the tooth enamel a lesser invasive method, experiments using X-Band and K-Band were performed, aiming to determine conditions that could be used in cases of accidental exposures. First, a small prism from the enamel was removed and ground with an agate mortar and pestle until particles reach a diameter of approximately less than 0.5 mm. This enamel extraction process resulted in lower signal artifact compared with the direct enamel extraction performed with a diamond burr abrasion. The manual grinding of the enamel does not lead to any induced ESR signal artifact, whereas the use of a diamond burr at low speed produces a signal artifact equivalent to the dosimetric signal induced by a dose of 500 mGy of gamma irradiation. A mass of 25 mg of enamel was removed from a sound molar tooth previously irradiated in vitro with a dose of 100 mGy. This amount of enamel was enough to detect the dosimetric signal in a standard X-Band spectrometer. However using a K-Band spectrometer, samples mass between 5 and 10 mg were sufficient to obtain the same sensitivity. An overall evaluation of the uncertainties involved in the process in this and other dosimetric assessments performed at our laboratory indicates that it is possible at K-Band to estimate a 100 mGy dose with 25% accuracy. In addition, the use of K-Band also presented higher sensitivity and allowed the use of smaller sample mass in comparison with X-Band. Finally, the restoration process performed on a tooth after extraction of the 25 mg of enamel is described. This was conducted by dental treatment using photopolymerizable resin which enabled complete recovery of the tooth from the functional and aesthetic viewpoint showing that this procedure can be minimally invasive.

  2. Retrospective biodosimetry with small tooth enamel samples using K-Band and X-Band

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Jorge A. [Departamento de Fisica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto, Sao Paulo (Brazil); Kinoshita, Angela [Departamento de Fisica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto, Sao Paulo (Brazil); Universidade Sagrado Coracao - USC, 17011-160 Bauru, Sao Paulo (Brazil); Leonor, Sergio J. [Departamento de Fisica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto, Sao Paulo (Brazil); Belmonte, Gustavo C. [Universidade Sagrado Coracao - USC, 17011-160 Bauru, Sao Paulo (Brazil); Baffa, Oswaldo, E-mail: baffa@usp.br [Departamento de Fisica, FFCLRP, Universidade de Sao Paulo, 14040-901 Ribeirao Preto, Sao Paulo (Brazil)

    2011-09-15

    In an attempt to make the in vitro electron spin resonance (ESR) retrospective dosimetry of the tooth enamel a lesser invasive method, experiments using X-Band and K-Band were performed, aiming to determine conditions that could be used in cases of accidental exposures. First, a small prism from the enamel was removed and ground with an agate mortar and pestle until particles reach a diameter of approximately less than 0.5 mm. This enamel extraction process resulted in lower signal artifact compared with the direct enamel extraction performed with a diamond burr abrasion. The manual grinding of the enamel does not lead to any induced ESR signal artifact, whereas the use of a diamond burr at low speed produces a signal artifact equivalent to the dosimetric signal induced by a dose of 500 mGy of gamma irradiation. A mass of 25 mg of enamel was removed from a sound molar tooth previously irradiated in vitro with a dose of 100 mGy. This amount of enamel was enough to detect the dosimetric signal in a standard X-Band spectrometer. However using a K-Band spectrometer, samples mass between 5 and 10 mg were sufficient to obtain the same sensitivity. An overall evaluation of the uncertainties involved in the process in this and other dosimetric assessments performed at our laboratory indicates that it is possible at K-Band to estimate a 100 mGy dose with 25% accuracy. In addition, the use of K-Band also presented higher sensitivity and allowed the use of smaller sample mass in comparison with X-Band. Finally, the restoration process performed on a tooth after extraction of the 25 mg of enamel is described. This was conducted by dental treatment using photopolymerizable resin which enabled complete recovery of the tooth from the functional and aesthetic viewpoint showing that this procedure can be minimally invasive.

  3. Large scale study of tooth enamel

    International Nuclear Information System (INIS)

    Human tooth enamel contains traces of foreign elements. The presence of these elements is related to the history and the environment of the human body and can be considered as the signature of perturbations which occur during the growth of a tooth. A map of the distribution of these traces on a large scale sample of the population will constitute a reference for further investigations of environmental effects. On hundred eighty samples of teeth were first analyzed using PIXE, backscattering and nuclear reaction techniques. The results were analyzed using statistical methods. Correlations between O, F, Na, P, Ca, Mn, Fe, Cu, Zn, Pb and Sr were observed and cluster analysis was in progress. The techniques described in the present work have been developed in order to establish a method for the exploration of very large samples of the Belgian population. (author)

  4. Large scale study of tooth enamel

    International Nuclear Information System (INIS)

    Human tooth enamel contains traces of foreign elements. The presence of these elements is related to the history and the environment of the human body and can be considered as the signature of perturbations which occur during the growth of a tooth. A map of the distribution of these traces on a large scale sample of the population will constitute a reference for further investigations of environmental effects. One hundred eighty samples of teeth were first analysed using PIXE, backscattering and nuclear reaction techniques. The results were analysed using statistical methods. Correlations between O, F, Na, P, Ca, Mn, Fe, Cu, Zn, Pb and Sr were observed and cluster analysis was in progress. The techniques described in the present work have been developed in order to establish a method for the exploration of very large samples of the Belgian population

  5. Gastroesophageal Reflux Disease and Tooth Erosion

    OpenAIRE

    Smales, Roger J.; John A. Kaidonis; Sarbin Ranjitkar

    2012-01-01

    The increasing prevalence of gastroesophageal reflux disease (GERD) in children and adults, and of “silent refluxers” in particular, increases the responsibility of dentists to be alert to this potentially severe condition when observing unexplained instances of tooth erosion. Although gastroesophageal reflux is a normal physiologic occurrence, excessive gastric and duodenal regurgitation combined with a decrease in normal protective mechanisms, including an adequate production of saliva, may...

  6. The evolution of tooth wear indices

    OpenAIRE

    Bardsley, Penny Fleur

    2008-01-01

    Tooth wear—attrition, erosion and abrasion—is perceived internationally as an ever-increasing problem. Clinical and epidemiological studies, however, are difficult to interpret and compare due to differences in terminology and the large number of indices that have been developed for diagnosing, grading and monitoring dental hard tissue loss. These indices have been designed to identify increasing severity and are usually numerical. Some record lesions on an aetiological basis (e.g. erosion in...

  7. Microhardness and chemical composition of human tooth

    OpenAIRE

    Gutiérrez-Salazar Maria del Pilar; Reyes-Gasga Jorge

    2003-01-01

    Hardness of human tooth, both in enamel and dentin, has been measured at different sites using a Vicker's diamond. In this work we show that these values are almost constant all along the enamel and dentin thicknesses. Indentations were done from outer enamel surface to inner dentin layer, going through the enamel-dentin junction, both in transverse and longitudinal samples. Geometrical well-shape indentation uniformity was checked both with light and with scanning electron microscopes, and t...

  8. Incremental growth of deciduous tooth enamel

    OpenAIRE

    Birch, W. J.

    2012-01-01

    Deciduous tooth formation begins before birth and ends after birth. This makes it more difficult to construct a continuous developmental chronology for deciduous teeth than for permanent teeth. The discovery of the neonatal line in enamel and confirmation that it marks birth, allowed the expansion of deciduous dental chronologies, which until this time had been largely based on qualitative descriptions. The aim of this study was to use the daily incremental record in deciduo...

  9. Tooth Regeneration with Stem Cell Sources

    OpenAIRE

    Neda Naghavi

    2014-01-01

    Introduction: During the last decade, advances in tissue engineering and stem cell-based tooth regeneration have provided realistic and attractive means of replacing lost or damaged teeth. The first adult stem cells isolated from dental tissues were dental pulp stem cells (DPSCs). When transplanted with hydroxyl apatite/tri calcium phosphate (HA/TCP) powder, they formed a dentin-like structure lined with odontoblast-like cells that surrounded a pulp-like interstitial tissue. DPSCs could di...

  10. Industrial noise and tooth wear – Experimental study

    OpenAIRE

    Cavacas, M. A.; Tavares, V.; Borrecho, G.; Oliveira, M. J.; Oliveira, P.; Brito, J; Águas, A.; Martins dos Santos, J.

    2015-01-01

    "Tooth wear is a complex multifactorial process that involves the loss of hard dental tissue. Parafunctional habits have been mentioned as a self-destructive process caused by stress, which results in hyperactivity of masticatory muscles. Stress manifests itself through teeth grinding, leading to progressive teeth wear. The effects of continuous exposure to industrial noise, a “stressor” agent, cannot be ignored and its effects on the teeth must be evaluated. Aims: The aim of t...

  11. Restoration of the root canal treated tooth.

    Science.gov (United States)

    Eliyas, S; Jalili, J; Martin, N

    2015-01-01

    When considering endodontically treated teeth, the quality of the restoration is important from the outset. It sheds light into possible causes of pulp necrosis or failure of endodontic treatment and influences the outcome of future endodontic treatment. A tooth undergoing endodontic treatment requires an effective coronal seal during and following completion of endodontic treatment. This paper discusses, using the available literature, the maintenance of optimal coronal seal and coronal integrity during and after root canal treatment. PMID:25613259

  12. Tooth matrix analysis for biomonitoring of organic chemical exposure: Current status, challenges, and opportunities.

    Science.gov (United States)

    Andra, Syam S; Austin, Christine; Arora, Manish

    2015-10-01

    Epidemiological evidence supports associations between prenatal exposure to environmental organic chemicals and childhood health impairments. Unlike the common choice of biological matrices such as urine and blood that can be limited by short half-lives for some chemicals, teeth provide a stable repository for chemicals with half-life in the order of decades. Given the potential of the tooth bio-matrix to study long-term exposures to environmental organic chemicals in human biomonitoring programs, it is important to be aware of possible pitfalls and potential opportunities to improve on the current analytical method for tooth organics analysis. We critically review previous results of studies of this topic. The major drawbacks and challenges in currently practiced concepts and analytical methods in utilizing tooth bio-matrix are (i) no consideration of external (from outer surface) or internal contamination (from micro-odontoblast processes), (ii) the misleading assumption that whole ground teeth represent prenatal exposures (latest formed dentine is lipid rich and therefore would absorb and accumulate more organic chemicals), (iii) reverse causality in exposure assessment due to whole ground teeth, and (iv) teeth are a precious bio-matrix and grinding them raises ethical concerns about appropriate use of a very limited resource in exposure biology and epidemiology studies. These can be overcome by addressing the important limitations and possible improvements with the analytical approach associated at each of the following steps: (i) tooth sample preparation to retain exposure timing, (ii) organics extraction and pre-concentration to detect ultra-trace levels of analytes, (iii) chromatography separation, (iv) mass spectrometric detection to detect multi-class organics simultaneously, and (v) method validation, especially to exclude chance findings. To highlight the proposed improvements we present findings from a pilot study that utilizes tooth matrix biomarkers to obtain trimester-specific exposure information for a range of organic chemicals. PMID:26219084

  13. Radiographic interpretation of experimental lesions in radicular tooth structure of human maxillary anterior teeth.

    Science.gov (United States)

    Bernier-Rodriguez, Joseph A; Sidow, Stephanie J; Joyce, Anthony P; McNally, Kathleen; McPherson, James C

    2008-12-01

    External resorption is often first detected radiographically. Early detection can lead to timely intervention and improvement of treatment outcome. The purpose of this study was to determine the minimal radicular defect size in maxillary anterior teeth that is radiographically detectable. Six teeth were selected in a cadaver maxilla (#6-11) and extracted. The teeth were then replanted in the maxilla, and three horizontally angled radiographs (0 degrees , 30 degrees from the mesial, and 30 degrees from the distal) were exposed as a baseline. Then, a sequence of tooth removal, placement of a 0.1-mm deep defect in the interproximal and midroot surface, tooth replantation, and radiograph exposure was begun and repeated eight times. Each time the defect depth was increased by 0.1 mm. Ten clinicians interpreted the subsequent radiographs to determine if they visualized a defect on each tooth and the location of the defect. The evaluators' ability to detect experimental lesions according to the depth of the defect was shown to be statistically significant for both tooth type and location of the radicular defect (analysis of variance, p < 0.05). The average size of defect needed for radiographic visualization was as follows: central incisor (0.28 mm on the interproximal [IP] and 0.74 mm on the midroot [MR] [palatal], lateral incisor (0.39 mm on the IP and 0.55 mm on the MR); and canine [0.45 mm on the IP and 0.71 mm on the MR). Based on the results of this study, the minimal defect size detected was 0.28 mm to 0.74 mm depending on defect location and tooth selected. PMID:19026875

  14. Radiosterilization of tooth pastes EF, MB, LK

    International Nuclear Information System (INIS)

    The effect of decontaminating doses of gamma rays (60Co, 10 Kr - 1.5 Mr) on the quality and biological activity of tooth pastes is studied. The radioresistance factors D10 of the dominating microorganisms in the studied pastes, namely Bac. subtilis, Staph. epidermidis, S. lutea, Ps. aeruginosa, Pen. notatum, Pen. chrysogenum, Asp. niger, C. parapsilosis, are determined. Ps aeruginosa appears to show the highest radiosensitivity - D10 = 20 Kr. The irradiation in the range 500 Kr - 1.5 Mr reveals that Ps. aeruginosa are inactivated with doses of 750 Kr while the inactivation of sporebearing bacteria and grampositive microorganisms starts at doses above 1 Mr. The lower values of radioresistance factors observed as compared to that established by the authors for cosmetic preparations henna and starch are due to radiosensitizing of microorganisms in a medium with higher water content. The radiolytic effect of water causes changes in consistency, odour, taste and colour of the tooth pastes and for that reason the radiosterilization of tooth pastes is not recommended. A mathematical model for irradiation of products contaminated with a variety of microorganisms is developed. Bac. subtilis - the most frequent and radioresistant pollutant - is suggested as a standard in selecting the proper sterilization procedure and in checking the efficiency of irradiation. 3 tabs, 3 figs, 6 refs

  15. ISS protocol for EPR tooth dosimetry

    International Nuclear Information System (INIS)

    The accuracy in Electron Paramagnetic Resonance (EPR) dose reconstruction with tooth enamel is affected by sample preparation, dosimetric signal amplitude evaluation and unknown dose estimate. Worldwide efforts in the field of EPR dose reconstruction with tooth enamel are focused on the optimization of the three mentioned steps in dose assessment. In the present work, the protocol implemented at ISS in the framework of the European Community Nuclear Fission Safety project 'Dose Reconstruction' is presented. A combined mechanical-chemical procedure for ground enamel sample preparation is used. The signal intensity evaluation is carried out with powder spectra simulation program. Finally, the unknown dose is evaluated individually for each sample with the additive dose method. The unknown dose is obtained by subtracting a mean native dose from the back-extrapolated dose. As an example of the capability of the ISS protocol in unknown dose evaluation, the results obtained in the framework of the 2nd International Intercomparison on EPR tooth enamel dosimetry are reported

  16. ESR dosimetry for atomic bomb survivors using shell buttons and tooth enamel

    International Nuclear Information System (INIS)

    Atomic bomb radiation doses to humans at Nagasaki and Hiroshima are investigated by electron spin resonance (ESR) from shell buttons and tooth enamel voluntarily supplied by survivors. A shell button gives a dose of 2.1+-0.2 Gy with ESR signals at g=2.001 and g=1.997 while the signal at g=1.997 for the tooth enamel of the same person is 1.9+-0.5 Gy. Other teeth show doses from about 0.5 Gy to 3 Gy. An apparent shielding converted to a concrete thickness is given using the T65D calculated in 1965. Teeth extracted during dental treatment should be preserved for cumulative radiation dosimetry. (author)

  17. The Association Between childhood Obesity and Tooth Eruption

    OpenAIRE

    MUST, AVIVA; Phillips, Sarah M.; TYBOR, DAVID J.; Lividini, Keith; Hayes, Catherine

    2012-01-01

    Obesity is a growth-promoting process as evidenced by its effect on the timing of puberty. Although studies are limited, obesity has been shown to affect the timing of tooth eruption. Both the timing and sequence of tooth eruption are important to overall oral health. The purpose of this study was to examine the association between obesity and tooth eruption. Data were combined from three consecutive cycles (2001–2006) of the National Health and Nutrition Examination Survey (NHANES) and analy...

  18. Hair keratin mutations in tooth enamel increase dental decay risk

    OpenAIRE

    Duverger, Olivier; Ohara, Takahiro; Shaffer, John R; Donahue, Danielle; Zerfas, Patricia; Dullnig, Andrew; Crecelius, Christopher; Beniash, Elia; Marazita, Mary L; Morasso, Maria I.

    2014-01-01

    Tooth enamel is the hardest substance in the human body and has a unique combination of hardness and fracture toughness that protects teeth from dental caries, the most common chronic disease worldwide. In addition to a high mineral content, tooth enamel comprises organic material that is important for mechanical performance and influences the initiation and progression of caries; however, the protein composition of tooth enamel has not been fully characterized. Here, we determined that epith...

  19. Bioengineering of a human whole tooth: progress and challenge

    OpenAIRE

    Zhang, Yanding; Chen, Yiping

    2014-01-01

    A major challenge in stem cell-based bioengineering of an implantable human tooth is to identify appropriate sources of postnatal stem cells that are odontogenic competent as the epithelial component due to the lack of enamel epithelial cells in adult teeth. In a recent issue (2013, 2:6) of Cell Regeneration, Cai and colleagues reported that epithelial sheets derived from human induced pluripotent stem cells (iPSCs) can functionally substitute for tooth germ epithelium to regenerate tooth-lik...

  20. Efficacy of Nonthermal Atmospheric Pressure Plasma for Tooth Bleaching

    OpenAIRE

    Nam, Seoul Hee; Lee, Hae June; Hong, Jin Woo; Kim, Gyoo Cheon

    2015-01-01

    The conventional light source used for tooth bleaching has the potential to cause thermal damage, and the actual role of the light source is doubtful. In this study, we evaluated bleaching efficacy, temperature, and morphological safety after tooth bleaching with nonthermal atmospheric pressure plasma. Tooth bleaching combined with plasma had improved efficacy in providing a higher level of brightness. The temperature of the pulp chamber was maintained around 37°C, indicating that the plasma ...

  1. A theropod tooth from the Late Triassic of southern Africa

    Indian Academy of Sciences (India)

    Sanghamitra Ray; Anusuya Chinsamy

    2002-06-01

    An isolated, large recurved and finely serrated tooth found associated with the prosauropod Euskelosaurus from the Late Triassic part of the Elliot Formation is described here. It is compared to the Triassic thecodonts and carnivorous dinosaurs and its possible affinity is discussed. The tooth possibly belongs to a basal theropod and shows some features similar to the allosauroids. This tooth is of significance, as dinosaur remains except for some footprints and trackways, are poorly known in the Late Triassic horizons of southern Africa.

  2. Is there a link between ovarian cancer and tooth agenesis?

    OpenAIRE

    Bonds, John; Pollan-White, Sarah; Xiang, Lilin; Mues, Gabriele; D’Souza, Rena

    2014-01-01

    An epidemiologic study from the year 2008 found a highly significant increase of congenital tooth agenesis in women with ovarian cancer suggesting that a common genetic etiology may predispose women to both conditions. The finding was reminiscent of a previously described family harboring an AXIN2 mutation which could be shown to segregate with both the tooth agenesis and the predisposition to colon cancer transmitted in this family. Since tooth agenesis as a marker for susceptibility to ovar...

  3. Protection and Reinforcement of Tooth Structures by Dental Coating Materials

    OpenAIRE

    Toru Nikaido; Rena Takahashi; Meu Ariyoshi; Junji Tagami; Alireza Sadr

    2012-01-01

    It has been proposed that a resin coating can serve as a means to protect dental structure after preparation of the tooth for indirect restorations, sealing the exposed dentin. The resin coating is applied on the cut surfaces immediately after tooth preparation and before making an impression by assembling a dentin bonding system and a flowable composite. Resin coatings minimize pulp irritation and improve the bond strength between a resin cement and tooth when bonding the restoration to toot...

  4. Enhanced Prediction of Gear Tooth Surface Fatigue Life Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sentient will develop an enhanced prediction of gear tooth surface fatigue life with rigorous analysis of the tribological phenomena that contribute to pitting...

  5. Msx1 Mutations: How Do They Cause Tooth Agenesis?

    OpenAIRE

    Wang, Y.; Kong, H; Mues, G.; D’Souza, R

    2011-01-01

    Mutations in the transcription factors PAX9 and MSX1 cause selective tooth agenesis in humans. In tooth bud mesenchyme of mice, both proteins are required for the expression of Bmp4, which is the key signaling factor for progression to the next step of tooth development. We have previously shown that Pax9 can transactivate a 2.4-kb Bmp4 promoter construct, and that most tooth-agenesis-causing PAX9 mutations impair DNA binding and Bmp4 promoter activation. We also found that Msx1 by itself rep...

  6. Tooth-marked small theropod bone: an extremely rare trace

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2001-01-01

    Tooth-marked dinosaur bones provide insight into feeding behaviours and biting strategies of theropod dinosaurs. The majority of theropod tooth marks reported to date have been found on herbivorous dinosaur bones, although some tyrannosaurid bones with tooth marks have also been reported. In 1988 a partial skeleton of the dromaeosaurid Saurornitholestes was collected from southern Alberta, Canada, that bore marks on one dentary. The location and morphology of the tooth marks suggests that a theropod (possible a juvenile tyrannosaurid) included a Saurornitholestes in its diet.

  7. Tooth’s Tensions Analysis of Face Worm Gears with Cylindrical Pinion Development of FEA

    OpenAIRE

    Ion Gavrila

    2009-01-01

    Tooths tension in lapping process for worm face gear is proposed. The stress analysis of the gear drive is performed using a three-dimensional finite element analysis. The developed simulation is illustrated with numerical examples. This complex and intuitive simulation was created with CAD-CAM, MATH-CAD and FEM support. This simulation contains data collected from EU standards.

  8. 21 CFR 872.3910 - Backing and facing for an artificial tooth.

    Science.gov (United States)

    2010-04-01

    ...false Backing and facing for an artificial tooth. 872.3910 Section 872...3910 Backing and facing for an artificial tooth. (a) Identification. A backing and facing for an artificial tooth is a device...

  9. Hierarchical structure and biomineralization in cricket tooth

    CERN Document Server

    Xing, Xueqing; Cai, Quan; Mo, Guang; Du, Rong; Chen, Zhongjun; Wu, Zhonghua

    2012-01-01

    Cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of the cricket teeth are always interested. Synchrotron radiation X-ray fluorescence, X-ray diffraction and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. Scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of the cricket teeth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. While, the interior of the teeth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points at the top of tooth cusp. The microfibrils aggregate random into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp was proposed and a d...

  10. Microhardness and chemical composition of human tooth

    Scientific Electronic Library Online (English)

    Maria del Pilar, Gutiérrez-Salazar; Jorge, Reyes-Gasga.

    2003-06-01

    Full Text Available Hardness of human tooth, both in enamel and dentin, has been measured at different sites using a Vicker's diamond. In this work we show that these values are almost constant all along the enamel and dentin thicknesses. Indentations were done from outer enamel surface to inner dentin layer, going thr [...] ough the enamel-dentin junction, both in transverse and longitudinal samples. Geometrical well-shape indentation uniformity was checked both with light and with scanning electron microscopes, and the chemical composition of the tooth was analyzed with characteristic X-ray energy dispersive spectroscopy. Hardness measurements were in the range from 270 to 360 VHN for enamel and 50 to 60 VHN for dentin. Cervical zone in longitudinal section showed the lowest value while in transverse sections the highest. All the hardness values were statically significative. Tour results indicate that the difference between enamel and dentin hardness has nothing to do with the content of Na, Cl and Mg, but the percentage of organic and inorganic materials in enamel and dentin.

  11. The challenges of treating a fused tooth.

    Science.gov (United States)

    Baratto-Filho, Flares; Leonardi, Denise Piotto; Crozeta, Bruno Monguilhott; Baratto, Samantha Pugsley; Campos, Edson Alves; Tomazinho, Flavia Sens Fagundes; Deliberador, Tatiana Miranda

    2012-01-01

    This paper describes and discusses the multidisciplinary treatment involving a permanent maxillary lateral incisor fused to a supernumerary tooth, both presenting pulp necrosis and periapical lesion. A 15-year-old male patient sought treatment complaining of pain, swelling and mobility on the maxillary right lateral incisor. After clinical and radiographic examination, root canal preparation was performed according to the crown-down technique and a calcium hydroxide dressing was placed for 15 days. The patient returned and the definitive endodontic filling was done with thermomechanical compaction of gutta-percha and sealer. After 18 months, clinical and radiographic examinations were carried out and no pain or swelling was reported. Two years after endodontic treatment, the patient returned for periodontal and cosmetic treatments. Nine months later, a cone-beam computed tomography (CBCT) revealed that the previously detected periodontal defect and periapical lesion were persistent. Apical endodontic surgery was indicated. The supernumerary tooth was removed, the communicating distal surface was filled and the surgical site received bioactive glass and demineralized bovine organic bone. The pathological tissue was submitted to histopathological examination and the diagnosis was periapical cyst. One year after the apical endodontic surgery, CBCT showed bone formation at maxillary lateral incisor apical area. Two years after the surgery, the restoration was replaced due to aesthetic reasons and periapical radiograph showed success after 5 years of treatment. A correct diagnosis and establishment of an adequate treatment plan resulted in a successful management of the case. PMID:22814696

  12. The lateral enamel lamina - component of each mammalian tooth primordium?.

    Czech Academy of Sciences Publication Activity Database

    Witter, K.; Matulová, Petra; Míšek, Ivan

    La Londe les Maures : COST, 2001. s. 74. [International conference on tooth morphogenesis and differrentiation /7./. 16.06.2001-21.06.2001, La Londe les Maures] R&D Projects: GA AV ?R IAA7039901; GA ?R GV304/01/P021 Keywords : tooth Subject RIV: EG - Zoology

  13. An Analysis of the Symptomatic Domains Most Relevant to Charcot Marie Tooth Neuropathy (CMT) Patients

    Science.gov (United States)

    2015-04-28

    Charcot Marie Tooth Disease (CMT); Hereditary Sensory and Motor Neuropathy; Nerve Compression Syndromes; Tooth Diseases; Congenital Abnormalities; Genetic Diseases, Inborn; Heredodegenerative Disorders, Nervous System

  14. The 4th international comparison on EPR dosimetry with tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Fattibene, P., E-mail: paola.fattibene@iss.it [Istituto Superiore di Sanita, Department of Technology and Health, Viale Regina Elena 299, I-00162 Rome (Italy); Wieser, A. [Helmholtz Zentrum Muenchen, Neuherberg D-85764 (Germany); Adolfsson, E. [Linkoeping University, SE-58185 Linkoeping (Sweden); Benevides, L.A. [Naval Dosimetry Center, Bethesda MD 20889-5600 (United States); Brai, M. [University of Palermo, I-90128 Palermo (Italy); Callens, F. [Ghent University, B-9000 Gent (Belgium); Chumak, V. [Research Center for Radiation Medicine AMS, 04050 Kiev (Ukraine); Ciesielski, B. [Medical University of Gdansk, 80-211 Gdansk (Poland); Della Monaca, S. [Istituto Superiore di Sanita, Department of Technology and Health, Viale Regina Elena 299, I-00162 Rome (Italy); Regina Elena Institute, I-00144 Rome (Italy); Emerich, K. [Medical University of Gdansk, 80-211 Gdansk (Poland); Department of Paediatric Dentistry, 80-208 Gdansk (Poland); Gustafsson, H. [Linkoeping University, SE-58185 Linkoeping (Sweden); Hirai, Y. [Radiation Effects Research Foundation, Minami-ku, Hiroshima 732-0815 (Japan); Hoshi, M. [Hiroshima University, Minami-ku, Hiroshima 734-8553 (Japan); Israelsson, A. [Linkoeping University, SE-58185 Linkoeping (Sweden); Ivannikov, A. [Medical Radiological Research Center, Obninsk, Kaluga region (Russian Federation); Ivanov, D. [Institute of Metal Physics, Yekaterinburg 620041 (Russian Federation); Kaminska, J. [Medical University of Gdansk, 80-211 Gdansk (Poland); Ke, Wu [Beijing Institute of Radiation Medicine, Beijing 100850 (China); Lund, E. [Linkoeping University, SE-58185 Linkoeping (Sweden); Marrale, M. [University of Palermo, I-90128 Palermo (Italy)

    2011-09-15

    This paper presents the results of the 4th International Comparison of in vitro electron paramagnetic resonance dosimetry with tooth enamel, where the performance parameters of tooth enamel dosimetry methods were compared among sixteen laboratories from all over the world. The participating laboratories were asked to determine a calibration curve with a set of tooth enamel powder samples provided by the organizers. Nine molar teeth extracted following medical indication from German donors and collected between 1997 and 2007 were prepared and irradiated at the Helmholtz Zentrum Muenchen. Five out of six samples were irradiated at 0.1, 0.2, 0.5, 1.0 and 1.5 Gy air kerma; and one unirradiated sample was kept as control. The doses delivered to the individual samples were unknown to the participants, who were asked to measure each sample nine times, and to report the EPR signal response, the mass of aliquots measured, and the parameters of EPR signal acquisition and signal evaluation. Critical dose and detection limit were calculated by the organizers on the basis of the calibration-curve parameters obtained at every laboratory. For calibration curves obtained by measuring every calibration sample three times, the mean value of the detection limit was 205 mGy, ranging from 56 to 649 mGy. The participants were also invited to provide the signal response and the nominal dose of their current dose calibration curve (wherever available), the critical dose and detection limit of which were also calculated by the organizers.

  15. Isolation of epithelial cells from tooth brush and gender identification by amplification of SRY gene

    Directory of Open Access Journals (Sweden)

    A Vikram Simha Reddy

    2011-01-01

    Full Text Available Introduction: This study determines the importance of tooth brush from which DNA can be isolated and used for sex determination in forensic analysis. Materials and Methods: A total of 30 samples were collected and stored at room temperature for different periods of time interval. The epithelial cells adhered to the bristles of tooth brush were collected and genomic DNA was extracted and quantified using Nanodrop 1000 spectrophotometer. Results: Gender identification was done by amplification of sex determining region on Y chromosome (SRY gene using real-time polymerase chain reaction and minimal amount of DNA (in pico grams with 100% sensitivity and 73.3% specificity, i.e., all male samples showed positive results and out of 15 female samples 4 showed false positive results, i.e wrongly identified as males. Conclusion: With this study, we conclude that PCR is a valuable and sensitive procedure where minute contamination may cause alteration in the result, i.e, 4 females showed false positive result. Minute amount of DNA in picograms, which was collected at different intervals is enough for amplification of SRY gene and tooth brush can be used as one of the very valuable sources of gender identification.

  16. Delayed tooth replantation: MTA as root canal filling

    Scientific Electronic Library Online (English)

    Sônia Regina, PANZARINI; Celso Koogi, SONODA; Célia Tomiko Matida Hamata, SAITO; Elizane Ferreira, HAMANAKA; Wilson Roberto, POI.

    Full Text Available MTA has been investigated as a root-end filling material. Its mechanism of action has some similarities to that of Ca(OH)2. The purpose of this study was to evaluate the repair process taking place in the delayed replantation of monkey teeth using calcium hydroxide and MTA as root canal filling mate [...] rials. Five monkeys had their lateral incisors extracted and bench-dried for 60 minutes. After root canal preparation, the teeth were assigned to two groups according to root canal filling material: I, calcium hydroxide; and II, MTA. The same treatment sequence was followed for both groups: coronal seal, periodontal ligament removal, immersion of the tooth in 2% acidulated-phosphate sodium fluoride, irrigation of the socket with saline and replantation. Both groups exhibited replacement resorption, areas of ankylosis and absence of inflammatory root resorption. Statistically similar results (p > 0.05) were observed for both groups regarding replacement root resorption, but the groups differed significantly (p

  17. Estimation of age based on tooth cementum annulations using three different microscopic methods

    Directory of Open Access Journals (Sweden)

    Siddharth Pundir

    2009-01-01

    Full Text Available Background: The hard tissues of human dentition are able to resist decay and degradation long after other tissues are lost. This resistance to decay has made teeth useful for calculation of age at death of an individual. Recent research indicates that tooth cementum annulations (TCA may be used more reliably than other morphological or histological traits of the adult skeleton for estimation of age. Objectives: The purpose of this study was to examine the correlation between age and the number of incremental lines in human dental cementum and to ascertain which, among three different forms of microscopy (light, polarized, phase-contrast was the most reliable method of studying cementum. Materials and Methods: The study sample consisted of 40 teeth that had been extracted from patients ranging in age from 20?70 years. Longitudinal ground sections of each tooth were prepared and examined under light microscopy, polarized microscopy, and phase-contrast microscopy. The images were magnified on a computer and the cemental lines were counted with the help of Image Analysis Pro 6.0 software. Only the dark lines were counted. Results: There was a strong positive correlation between the estimated age and calculated age when phase-contrast microscopy was used; the correlation was less for light and polarized microscopy. Our results suggest that there is no significant influence of sex, age, periodontal disease, or tooth type on age estimation by the TCA method. This suggests that the accuracy and repeatability of the method is not dependent on tooth type or location and that this method can be applied to the general population regardless of systemic or periodontal health. Conclusion: With this study we conclude that among the methods of counting incremental lines by various types of microscopy phase-contrast microscopy improves the accuracy of age estimation and may serve as a valuable aid in forensic identification.

  18. Molecular phylogenetic inference from saber-toothed cat fossils of Rancho La Brea.

    OpenAIRE

    Janczewski, D N; Yuhki, N; Gilbert, D A; Jefferson, G T; O'Brien, S. J.

    1992-01-01

    A method for the successful extraction of sequestered cellular DNA from 14,000-year-old fossil bones was developed and applied to asphalt-preserved specimens of the extinct saber-toothed cat, Smilodon fatalis. Two distinct gene segments, the mitochondrial gene for 12S rRNA and nuclear FLA-I (the feline class I major histocompatibility complex gene), from three different individual fossil specimens were cloned and sequenced after PCR amplification. Comparison of fossil-derived DNA sequences to...

  19. Collagen analysis in human tooth germ papillae

    Scientific Electronic Library Online (English)

    Ivete Jorge, Abrahão; Manoela Domingues, Martins; Emílio, Katayama; João Humberto, Antoniazzi; Angelo, Segmentilli; Márcia Martins, Marques.

    Full Text Available A matriz extracelular (MEC) tem um papel importante na regulação do crescimento e na diferenciação e organização dos tecidos. Com base nestes aspectos o objetivo do deste estudo foi analisar o colágeno, maior componente orgânico da MEC da polpa dentária, na papila de germes dentários humanos, em dif [...] erentes fases do desenvolvimento. Foram obtidos fragmentos de maxilas e mandíbulas de 9 fetos humanos com 10 a 22 semanas de vida intra-uterina, dos quais foram analisados 16 germes dentários (1 em estágio de capuz, 8 em estágio de campânula precoce e 7 em estágio de campânula tardia). Secções histológicas seriadas foram coradas com hematoxilina e eosina, tricrômico de Masson e técnica de coloração do picrosirius. Ambos os tipos de colágeno na papila dentária foram somente detectados pela técnica de coloração do picrosirius usando microscopia de luz polarizada. Colágeno tipo III foi detectado em todas as amostras. Colágeno tipo I estava presente em áreas focais da papila dental em algumas amostras. Concluiu-se que o colágeno tipo III mostrou-se um componente regular da papila de germes dentários humanos, enquanto o colágeno tipo I esteve presente em quantidade significativamente menor. Abstract in english The extracellular matrix (ECM) performs a very important role in growth regulation and tissue differentiation and organization. In view of this, the purpose of this study was to analyze the collagen, the major organic component of dental pulp ECM, in papillae of human tooth germs in different develo [...] pmental phases. The maxillas and mandibles of 9 human fetuses ranging from 10 to 22 weeks of intrauterine life were removed and 16 tooth germs (1 in the cap stage, 8 in the early bell stage and 7 in the late bell stage) were obtained. The pieces were processed for histological analysis and stained with hematoxylin-eosin, Masson's Trichrome and picrosirius staining technique. Both types of collagen in the dental papilla were only detected by the picrosirius staining technique under polarized light microscopy. Type III collagen was detected in all specimens. Type I collagen was present in focal areas of the dental papilla only in some specimens. In conclusion, the findings of this study showed that type III collagen is a regular component of the papillae of human tooth germs whereas type I collagen is present in a significantly lesser amount.

  20. Effect of fluorides from various restorative materials on remineralization of adjacent tooth: An in vitro study

    OpenAIRE

    Baliga M; Bhat S

    2010-01-01

    The aim of the study was to evaluate the extent of surface zone remineralization and the effect of fluoride at the inter-proximal adjacent tooth surface, using restorative materials FusionAlloy, Ketac-Fil and Heliomolar. Ninety extracted molar teeth were used of which 45 were placed in artificial caries for 10 weeks. The remaining 45 teeth were filled with the respective restorative materials, mounted with the artificial carious teeth in proximal contact with plaster and placed in artificial ...

  1. Effects of Ion-Releasing Tooth-Coating Material on Demineralization of Bovine Tooth Enamel

    OpenAIRE

    Koji Kawasaki; Masaki Kambara

    2014-01-01

    We compared the effect of a novel ion-releasing tooth-coating material that contained S-PRG (surface-reaction type prereacted glass-ionomer) filler to that of non-S-PRG filler and nail varnish on the demineralization of bovine enamel subsurface lesions. The demineralization process of bovine enamel was examined using quantitative light-induced fluorescence (QLF) and electron probe microanalyzer (EPMA) measurement. Ion concentrations in demineralizing solution were measured using inductively c...

  2. Unusual intraosseous transmigration of impacted tooth

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Santosh; Urala, Arun Srinivas; Kamath, Abhay Taranath; Jayaswal, Priyanka; Valiathan, Ashima [Manipal College of Dental Sciences, Manipal (India)

    2012-03-15

    Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.

  3. Unusual intraosseous transmigration of impacted tooth

    International Nuclear Information System (INIS)

    Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.

  4. Abrasive Wear of Digger Tooth Steel

    Directory of Open Access Journals (Sweden)

    Hussein Sarhan sarhan, Nofal Al-Araji, Rateb Issa , Mohammad Alia

    2011-08-01

    Full Text Available The influence of silicon carbide SiC abrasive particles of 20, 30, 40, 50 and60?m size on carburized digger tooth steel was studied. Four types of steel, withdifferent hardness, were tested at two constant linear sliding speeds and undervarious loads of 10, 20, 30, 40 and 50N. Tests were carried out for sliding time of0.5, 1.0, 1.5, 2.0 and 2.5min. Experimental results showed that there wasconsistent reduction in abrasive wear as the hardness of the materials wasincreased. It was found that wear increased with the increase of applied load,linear sliding speed and sliding time. Also, it was noticed that the wear increasedwith increase in abrasive particle size, and the most effective size was 40 ?m.SEM observations of the worm surface showed that the cutting and ploughingwere the dominant abrasive wear mechanisms.

  5. ATTITUDE AND KNOWLEDGE TOWARDS TOOTH AVULSION AMONG SPORTS TEACHERS

    Directory of Open Access Journals (Sweden)

    FARHEEN USTAD

    2013-05-01

    Full Text Available Background: Tooth avulsion is one of the commonest types of physical sport injury. Themanagement of these cases is critical in order to prevent complete loss of tooth and its subsequentconsequences. The prognosis of such avulsed tooth depends on prompt treatment. The emergencymanagement of such avulsed tooth is made by the sports teacher who is present at the sports ground. Thefirst–aid knowledge about tooth avulsion is must for the sports teacher. Aim: The objective of the presentstudy was to evaluate the knowledge about management of tooth avulsion among sports teachers inAhmednagar District. Methods: A sample of 60 sports teachers were interviewed from different schools.The data was collected using a self administered questionnaire containing seven items which wasdistributed among the sports teacher from different schools. Results: we found that 90% of the sportsteachers were not having the first-aid knowledge about the emergency management of avulsed tooth andthe benefit of timely care. This demands an effort to properly educate sports teachers about first-aidmanagement and consequently change their attitude towards dental trauma.

  6. Anomalies of tooth formation in hypohidrotic ectodermal dysplasia.

    DEFF Research Database (Denmark)

    Lexner, Michala O; Bardow, Allan

    2007-01-01

    OBJECTIVE: The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous females, enabling an earlier diagnosis, and therefore, better treatment and genetic counselling. METHODS: Anomalies of tooth formation were examined using panoramic radiographs, dental casts and oral photographs in hemizygous males and heterozygous females who were identified by molecular genetic analysis. The results were compared to existing controls and normative data. RESULTS: All affected males had multiple missing permanent teeth and tooth malformations. The heterozygous females had a significantly higher frequency of agenesis of permanent teeth compared to normative data. The heterozygous females had an increased prevalence of tooth malformations and reduced tooth size, especially in the mesiodistal dimension. CONCLUSIONS: We conclude that observed anomalies of tooth formation may be used as dental biomarkers in the clinical identification of potentially heterozygous females. Udgivelsesdato: 2007-Jan

  7. Roles of Wnt inhibitory factor 1 during tooth morphogenesis.

    Science.gov (United States)

    Lee, Min-Jung; Kim, Eun-Jung; Li, Liwen; Jung, Han-Sung

    2015-10-01

    The activation of Wingless-type (Wnt)/?-catenin signaling is of fundamental importance in organogenesis. Wnt signaling is also known to regulate signaling crucial for tooth development. However, the underlying mechanism of Wnt activation or inhibition remains largely unknown. Here, we demonstrate that Wnt inhibitory factor 1 (Wif1), a secreted Wnt antagonist, localizes to the dental epithelium and mesenchyme during early tooth development. Specifically, Wif1 is strictly expressed in the enamel knot at embryonic day 14.5 (E14.5) and E16.5. The functional significance of Wif1 during tooth morphogenesis remains to be clarified. Our results reveal that the promotion of apoptosis by the knockdown of Wif1 leads to a delay in an early event during tooth development. This study therefore provides novel insights into the role of Wif1 and validates Wif1 as a potent target in WNT signaling during tooth development. We suggest that the enamel knots are central regulators of tooth development. Furthermore, Wif1 localizes to the enamel knot in which Wif1 regulates apoptosis by mediating and regulating Wnt-?-catenin signaling. Thus, Wif1 plays an essential role in tooth development. PMID:25893927

  8. The effect of nano-hydroxyappatite solution on the permanent tooth remineralization following exposure to soft beer (in situ

    Directory of Open Access Journals (Sweden)

    Haghgoo Roza

    2015-01-01

    Full Text Available   Background and Aims: The main cause of erosion is acid exposure . Side effects of erosion necessitate therapeutic agents’ uses. The aim of this study was to investigate the effects of nano- hydroxy apatite in tooth remineralization following exposure to soft beer.   Materials and Methods: This in vitro experimental study was conducted on 18 human impacted third molars that had been surgically extracted. The microhardness of specimens was measured. Then teeth were exposed to soft beer and their secondary microhardness was measured. The teeth were divided into 2 groups (water and nano-hydroxy apatite solution and were placed on 9 orthodontics appliances and delivered to 9 volunteers. These volunteers placed the tooth on one side in water for 5 minutes and the tooth in opposite side in nano-hydroxyapatite solution. This application was repeated 6 times a day for 10 days. The microhardness of teeth was measured again. Data were analyzed using Paired T-test.   Results: The tooth enamel microhardness reduced after exposure to soft beer significantly (P=0.04. The microhardness of 9 teeth after being in water showed significant changes (P=0.012. The microhardness of 9 teeth significantly changed after exposure to nano -hydroxyapatite solution (P=0.001 .   Conclusion: Based on the results of this study, 10% solution of nano- hydroxy appatite could restore the erosive lesions .

  9. Impact Damage Evaluation Method of Friction Disc Based on High-Speed Photography and Tooth-Root Stress Coupling

    Science.gov (United States)

    Yin, L.; Shao, Y. M.; Liu, J.; Zheng, H. L.

    2015-07-01

    The stability of friction disc could be seriously affected by the tooth surface damage due to poor working conditions of the wet multi-disc brake in heavy trucks. There are few current works focused on the damage of the friction disc caused by torsion-vibration impacts. Hence, it is necessary to investigate its damage mechanisms and evaluation methods. In this paper, a damage mechanism description and evaluation method of a friction disc based on the high-speed photography and tooth-root stress coupling is proposed. According to the HighSpeed Photography, the collision process between the friction disc and hub is recorded, which can be used to determine the contact position and deformation. Combined with the strain-stress data obtained by the strain gauge at the place of the tooth-root, the impact force and property are studied. In order to obtain the evaluation method, the damage surface morphology data of the friction disc extracted by 3D Super Depth Digital Microscope (VH-Z100R) is compared with the impact force and property. The quantitative relationships between the amount of deformation and collision number are obtained using a fitting analysis method. The experimental results show that the damage of the friction disc can be evaluated by the proposed impact damage evaluation method based on the high-speed photography and tooth-root stress coupling.

  10. Tooth loss prevalence among cardiac males and females

    International Nuclear Information System (INIS)

    Objective of study was to observe differences of tooth loss prevalence in males and females with Cardiac diseases Poor oral health, tooth loss and periodontal diseases have been reported to be associated with coronary heart diseases. Studies report gender differences in prevalence of cardiac diseases and tooth loss. This paper presents gender differences of tooth loss in cardiac patients of a cardiac hospital of Lahore, Pakistan. Methodology: Age matched Cardiac males and females attending OPD of the Punjab Institute of Cardiology (PIC), Lahore were included in the study. Personal and health-related information were questioned and noted. Oral examination was performed for recording of missing teeth. 1200 CHD study subjects with age-range of 30 to 80 years were enrolled for study. 1045 age matched, 766 (73.30%) males and 279 (26.70%) females were examined for tooth loss. 852 (81.53%) genders had at least one tooth missing. 599 (78.19) males and 253 (90.68%) females were observed with mean tooth loss of 7.5 (SD 8.720) and 11.15 (SD 10.375)respectively statistical association among them was also significant (P= 0.000) with OR of 2.339. More subjects (76.29%) showed a loss of 1-15 teeth that I was also significant among males and females. Tooth loss was significant in age groups of 41-50 years (P=0.001) and 51-60 years (P=0.000) Gender differences of tooth loss prevalence among CHD Subjects were significant with more risk for males as compared to females. (author)

  11. Tooth bleaching--a critical review of the biological aspects

    DEFF Research Database (Denmark)

    Dahl, J E; Pallesen, Ulla

    2003-01-01

    Present tooth-bleaching techniques are based upon hydrogen peroxide as the active agent. It is applied directly, or produced in a chemical reaction from sodium perborate or carbamide peroxide. More than 90% immediate success has been reported for intracoronal bleaching of non-vital teeth, and in the period of 1-8 years' observation time, from 10 to 40% of the initially successfully treated teeth needed re-treatment. Cervical root resorption is a possible consequence of internal bleaching and is more frequently observed in teeth treated with the thermo-catalytic procedure. When the external tooth-bleaching technique is used, the first subjective change in tooth color may be observed after 2-4 nights of tooth bleaching, and more than 90% satisfactory results have been reported. Tooth sensitivity is a common side-effect of external tooth bleaching observed in 15%-78% of the patients, but clinical studies addressing the risk of other adverse effects are lacking. Direct contact with hydrogen peroxide induced genotoxic effects in bacteria and cultured cells, whereas the effect was reduced or abolished in the presence of metabolizing enzymes. Several tumor-promoting studies, including the hamster cheek pouch model, indicated that hydrogen peroxide might act as a promoter. Multiple exposures of hydrogen peroxide have resulted in localized effects on the gastric mucosa, decreased food consumption, reduced weight gain, and blood chemistry changes in mice and rats. Our risk assessment revealed that a sufficient safety level was not reached in certain clinical situations of external tooth bleaching, such as bleaching one tooth arch with 35% carbamide peroxide, using several applications per day of 22% carbamide peroxide, and bleaching both arches simultaneously with 22% carbamide peroxide. The recommendation is to avoid using concentrations higher than 10% carbamide peroxide when one performs external bleaching. We advocate a selective use of external tooth bleaching based on high ethical standards and professional judgment.

  12. Burried broken extraction instrument fragment

    OpenAIRE

    Balaji, S. M.

    2013-01-01

    Despite adequate effort to perform tooth removal carefully, some accidents may happen when defective instruments are unknowingly used. This article reports of a non-symptomatic case of a retained fractured dental elevator tip during an uneventful extraction a decade earlier. Patient was not aware till routine radiographic examination revealed its presence. Use of three dimensional imaging techniques in this case is highlighted. Rarely, instruments breakage may occur during surgical procedures...

  13. Axis Inhibition Protein 2 (AXIN2) Polymorphisms and Tooth Agenesis

    OpenAIRE

    Callahan, N; Modesto, A.; Meira, R; Seymen, F; Patir, A; Vieira, AR

    2008-01-01

    Tooth agenesis is a common congenital disorder that affects almost 20 percent of the world’s population. A number of different genes have been shown to be associated with cases of tooth agenesis including AXIN2, IRF6, FGFR1, MSX1, PAX9, and TGFA. Of particular interest is AXIN2, which was linked to two families segregating oligodontia and colorectal cancer. We studied two collections of families affected with tooth agenesis and tested them for association with AXIN2. Significant association b...

  14. Study on differences of radiosensitivity of human tooth enamel

    International Nuclear Information System (INIS)

    To study differences of radiosensitivity of human tooth enamel, 84 tooth enamel samples from 5 subjects were separated, and irradiated with radiation dose of 5 Gy from 60Co ? rays. After irradiation each sample was measured by ESR technique. Experimental results indicate that some difference in radiosensitivity exists for teeth from each subject (coefficients of variation of each subject range from 9.3% to 14.0%). Nevertheless, the mean values for all teeth of each subject among 5 subjects agree within the range of 325.77 to 386.80. It shows that the radiosensitivity of tooth enamel is basically uniform

  15. A local intercomparison study of ESR dosimetry using tooth enamel

    International Nuclear Information System (INIS)

    Using electron spin resonance (ESR), tooth enamel is a possible dosimeter in case of a radiation accident. To check the present status of this technique, we conducted a local intercomparison study. We irradiated several samples of tooth enamel with a 60Co source. Three institutes in Belgium and The Netherlands recorded the ESR signal of the samples. The results of the measurements and the methods used are compared. It is concluded that ESR on tooth enamel can be a useful technique in accident dosimetry, provided further research is done. (author)

  16. Long-term neuroplasticity of the face primary motor cortex and adjacent somatosensory cortex induced by tooth loss can be reversed following dental implant replacement in rats.

    Science.gov (United States)

    Avivi-Arber, Limor; Lee, Jye-Chang; Sood, Mandeep; Lakschevitz, Flavia; Fung, Michelle; Barashi-Gozal, Maayan; Glogauer, Michael; Sessle, Barry J

    2015-11-01

    Tooth loss is common, and exploring the neuroplastic capacity of the face primary motor cortex (face-M1) and adjacent primary somatosensory cortex (face-S1) is crucial for understanding how subjects adapt to tooth loss and their prosthetic replacement. The aim was to test if functional reorganization of jaw and tongue motor representations in the rat face-M1 and face-S1 occurs following tooth extraction, and if subsequent dental implant placement can reverse this neuroplasticity. Rats (n?=?22) had the right maxillary molar teeth extracted under local and general anesthesia. One month later, seven rats had dental implant placement into healed extraction sites. Naive rats (n?=?8) received no surgical treatment. Intracortical microstimulation (ICMS) and recording of evoked jaw and tongue electromyographic responses were used to define jaw and tongue motor representations at 1 month (n?=?8) or 2 months (n?=?7) postextraction, 1 month postimplant placement, and at 1-2 months in naive rats. There were no significant differences across study groups in the onset latencies of the ICMS-evoked responses (P?>?0.05), but in comparison with naive rats, tooth extraction caused a significant (P?implant placement reversed the extraction-induced changes in face-S1, and in face-M1 the number of jaw sites even increased as compared to naive rats. These novel findings suggest that face-M1 and adjacent face-S1 may play a role in adaptive mechanisms related to tooth loss and their replacement with dental implants. J. Comp. Neurol. 523:2372-2389, 2015. © 2015 Wiley Periodicals, Inc. PMID:25921658

  17. Ridge Alterations Post-extraction in the Esthetic Zone: A 3D Analysis with CBCT

    OpenAIRE

    Chappuis, V.; Engel, O.; M. Reyes; K. Shahim; Nolte, L. -P.; Buser, D

    2013-01-01

    Dimensional alterations of the facial bone wall following tooth extractions in the esthetic zone have a profound effect on treatment outcomes. This prospective study in 39 patients is the first to investigate three-dimensional (3D) alterations of facial bone in the esthetic zone during the initial 8 wks following flapless tooth extraction. A novel 3D analysis was carried out, based on 2 consecutive cone beam computed tomographies (CBCTs). A risk zone for significant bone resorption was identi...

  18. [Nasal cavity supernumerary tooth and maxillary sinusitis: one case reported].

    Science.gov (United States)

    Guo, Guangliang; Hu, Limin; Lu, Yuan

    2015-08-01

    Supernumerary tooth is a rare case. This report described a case of nasal cavity supernumerary tooth association with maxillary sinusitis. A 28-year-old male patient reported with the chief complaint of nasal obstruction, headache and purulent secretion for the past three months. Clinic examination and CT examination showed that there was a supernumerary tooth in the right nasal bottom, and maxillary sinus was infected in the same side. This patient was performed supernumerary tooth removing and given antibiotics for 3 days. Ten days after the operation, there was no clinical symptoms, and nasal bottom mucosa was normal. After 3 months of follow-up, reexamination of coronal CT scan appeared normal. PMID:26665468

  19. Geographic Variations in the EPR Spectrum of Tooth Enamel

    International Nuclear Information System (INIS)

    The presence of stable radiation-induced radicals in the mineral component of tooth enamel allows use of this material as a biological dosemeter. Estimation of the dose absorbed in tooth enamel can be done by EPR. Generally, for the purpose of dose reconstruction, the EPR spectrum of tooth enamel is interpreted in terms of two main components. The first is a broad background signal often called the native signal centered at a g value of 2.0045. The origin of this signal is not precisely known. The second main component in the tooth enamel spectrum is purely radiation induced and can be used for retrospective dosimetry. Internal structure of the native signal and variations of its amplitude and linewidth were investigated for the samples prepared from modern teeth obtained from different geographic locations (USA and Russia). Possible reasons for the variations observed are discussed as are the potential effects of the variations on the reliability of dose estimation. (author)

  20. Analysis of absorbed dose to tooth enamel for ESR dosimetry

    International Nuclear Information System (INIS)

    Absorbed dose to tooth enamel was quantitatively correlated to organ doses by Monte Carlo calculations using the Electron Gamma Shower Code Version 4 for the Electron Spin Resonance (ESR) dosimetry using teeth. A region for teeth was newly added to a mathematical human model. Kerma coefficients for whole tooth and enamel part were prepared to estimate the dose to tooth enamel. Experiments were also carried out with a physical head phantom, which is made of tissue equivalent materials. Tooth samples and thermo-luminescence dosimeters (TLDs) of CaSO4 crystal were set at the teeth position in the head phantom. Addition Monte Carlo calculations were performed to verify the results of the experiments by using a Voxel-type phantom reconstructed from computed tomographic (CT) images of the physical phantom. The obtained data are to be useful for retrospective dose assessments in past radiation events by the ESR dosimetry with teeth. (author)

  1. Seal Out Tooth Decay: A Fact Sheet for Parents

    Science.gov (United States)

    ... Institute of Dental and Craniofacial Research Seal Out Tooth Decay A Fact Sheet for Parents What are dental sealants? Sealants are thin, plastic coatings painted on the chewing surfaces of the back ...

  2. Anomalies of tooth formation in hypohidrotic ectodermal dysplasia

    DEFF Research Database (Denmark)

    Lexner, Michala O; Bardow, Allan; Hertz, Jens Michael; Almer, Lis Inge; Kreiborg, Sven

    2007-01-01

    OBJECTIVE: The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heteroz...

  3. Moxel: A molar tooth voxel model for dosimetric studies

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, P., E-mail: paolo.ferrari@enea.i [ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, ION-IRP, Radiation Protection Institute, 16 Via dei Colli, 40136 Bologna (Italy); Gualdrini, G. [ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, ION-IRP, Radiation Protection Institute, 16 Via dei Colli, 40136 Bologna (Italy); Fattibene, P. [Istituto Superiore di Sanita, Department of Technology and Health, Viale Regina Elena 299, I-00161 Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Roma, Gruppo Collegato Sanita, Viale Regina Elena 299, I-00161 Roma (Italy); Veronese, I. [Universita degli Studi di Milano, Dipartimento di Fisica, Via Celoria 16, 20133 Milano (Italy); INFN, Sezione di Milano, Via Celoria 16, 20133 Milano (Italy)

    2010-02-15

    Stylized numerical models of the tooth are usually employed in qualification procedure related to Electronic Paramagnetic Resonance in long-term accidental contamination dose reconstruction. In this work a voxel model was developed from the microCT image data set of a human non contaminated molar tooth. A stylized model, reproducing the characteristics of the voxel model, was also created in order to investigate the level of accuracy that can be obtained in this kind of study.

  4. A conservative approach toward restoration of fractured anterior tooth

    OpenAIRE

    Goenka, Puneet; Sarawgi, Aditi; Dutta, Samir

    2012-01-01

    Reattachment of the fractured anterior tooth is a highly conservative and aesthetic treatment that has gained popularity in the recent past. Presented here is one such case in which a combination of external enamel bevel and internal dentinal groove has been used to enhance the bonding between the fractured fragment and the remaining tooth. The treatment was found to be successful both functionally and aesthetically at the 18-month follow-up.

  5. Anomalies of tooth formation in hypohidrotic ectodermal dysplasia

    DEFF Research Database (Denmark)

    Lexner, Michala Oron; Bardow, Allan; Hertz, Jens Michael; Nielsen, Lis; Kreiborg, Sven

    2007-01-01

    The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous femal...

  6. Inflammatory side effects associated with orthodontic tooth movement

    OpenAIRE

    Giannopoulou, Catherine

    2009-01-01

    Orthodontic tooth movement is induced my mechanical stimuli and facilitated by the remodeling of the periodontal ligament and alveolar bone. The remodeling activities and the ultimately tooth displacement are the consequence of an inflammatory process. Vascular and cellular changes were the first events to be recognized and described. With the advancement of research techniques an important number of inflammatory mediators, growth factors, neuropeptides and metabolites of arachidonic acid hav...

  7. On the periodontal ligament representation in orthodontic tooth movement modelisation

    OpenAIRE

    Mengoni, Marlène; Ponthot, Jean-Philippe

    2011-01-01

    Orthodontic tooth movement (OTM) is the result of bone remodeling at the interface with the periodontal ligament (PDL) around a mechanically loaded tooth in response to a biomechanical stimulus. Modeling of the PDL therefore plays an important role in the process of modeling OTM. However when producing a finite element model from clinical computer tomography data, the PDL cannot be segmented and its geometry is approximated by many authors from the root geometry. The aim of this study is t...

  8. Stem cell-based biological tooth repair and regeneration

    OpenAIRE

    Volponi, Ana Angelova; Pang, Yvonne; Sharpe, Paul T.

    2010-01-01

    Teeth exhibit limited repair in response to damage, and dental pulp stem cells probably provide a source of cells to replace those damaged and to facilitate repair. Stem cells in other parts of the tooth, such as the periodontal ligament and growing roots, play more dynamic roles in tooth function and development. Dental stem cells can be obtained with ease, making them an attractive source of autologous stem cells for use in restoring vital pulp tissue removed because of infection, in regene...

  9. Three-dimensional analysis of mandibular growth and tooth eruption

    DEFF Research Database (Denmark)

    Krarup, S.; Darvann, Tron Andre; Larsen, Per; Marsh, J.L.; Kreiborg, S.

    2005-01-01

    Normal and abnormal jaw growth and tooth eruption are topics of great importance for several dental and medical disciplines. Thus far, clinical studies on these topics have used two-dimensional (2D) radiographic techniques. The purpose of the present study was to analyse normal mandibular growth and tooth eruption in three dimensions based on computer tomography (CT) scans, extending the principles of mandibular growth analysis proposed by Bjork in 1969 from two to three dimensions. As longitudi...

  10. Common developmental pathways link tooth shape to regeneration

    OpenAIRE

    Fraser, Gareth J; Bloomquist, Ryan F.; Streelman, J Todd

    2013-01-01

    In many non-mammalian vertebrates, adult dentitions result from cyclical rounds of tooth regeneration wherein simple unicuspid teeth are replaced by more complex forms. Therefore and by contrast to mammalian models, the numerical majority of vertebrate teeth develop shape during the process of replacement. Here, we exploit the dental diversity of Lake Malawi cichlid fishes to ask how vertebrates generally replace their dentition and in turn how this process acts to influence resulting tooth m...

  11. Is there a link between ovarian cancer and tooth agenesis?

    Science.gov (United States)

    Bonds, John; Pollan-White, Sarah; Xiang, Lilin; Mues, Gabriele; D'Souza, Rena

    2014-04-01

    An epidemiologic study from the year 2008 found a highly significant increase of congenital tooth agenesis in women with ovarian cancer suggesting that a common genetic etiology may predispose women to both conditions. The finding was reminiscent of a previously described family harboring an AXIN2 mutation which could be shown to segregate with both the tooth agenesis and the predisposition to colon cancer transmitted in this family. Since tooth agenesis as a marker for susceptibility to ovarian cancer would be of great relevance to both oncologists and women with inborn missing teeth, the relationship between the two disorders requires a thorough assessment. We examined DNA samples from the ovarian cancer patients who participated in the original study, to look for a possible genetic connection between their ovarian malignancies and tooth agenesis. MSX1, PAX9, AXIN2, EDA, WNT10A, BARX and BRCA1 genes were selected for sequence analysis as they may cause tooth agenesis, are expressed in the female reproductive system, and/or are involved in tumorigenesis in general or specifically in the ovary. Our study revealed evidence that one half of the dually affected patients had an independent causation of the two conditions, thus reducing the previously estimated ovarian cancer risk for women with congenital tooth agenesis quite significantly. PMID:24631698

  12. Novel PAX9 mutations cause non-syndromic tooth agenesis.

    Science.gov (United States)

    Mitsui, S N; Yasue, A; Masuda, K; Watanabe, K; Horiuchi, S; Imoto, I; Tanaka, E

    2014-03-01

    PAX9 is a transcription factor expressed in the tooth mesenchyme during tooth morphogenesis. In Pax9-null mice, tooth development is arrested at the bud stage. In humans, heterozygous mutations in PAX9 have been associated with non-syndromic tooth agenesis, predominantly in the molars. Here, we report 2 novel mutations in the paired domain of PAX9, a three-nucleotide deletion (73-75 delATC) and a missense mutation (C146T), in two unrelated Japanese patients with non-syndromic tooth agenesis. The individual with the 73-75del ATC mutation was missing all maxillary molars and mandibular second and third molars. The individual with the C146T mutation was missing the mandibular central incisors, maxillary second premolars, and first molars, along with all second and third molars. Both mutations affected amino acids that are highly conserved among different species and are critical for DNA binding. When both mutants were transfected to COS7 cells, nuclear localization of PAX9 proteins was not affected. However, reduced expression of the mutant proteins and almost no transcriptional activity of the target BMP4 gene were observed, suggesting haploinsufficiency of PAX9 as the cause of non-syndromic tooth agenesis. PMID:24436340

  13. Intentional reim plantation of a tooth with severe periodontal involvement using enamel matrix derivative in combination with guided tissue regeneration and bone grafting: a case report.

    Science.gov (United States)

    Sugai, Kenji; Sato, Shuichi; Suzuki, Kuniharu; Ito, Koichi

    2008-02-01

    This case involved the intentional reimplantation of a tooth with severe periodontal involvement using regenerative therapies. The maxillary left central incisor was intentionally extracted, enamel matrix derivative (EMD) was applied, and the tooth was repositioned accurately. The bone defect was filled with a xenograft and a demineralized freeze-dried bone allograft, and a guided tissue regeneration membrane was adapted over the site. After 5 years, a reduction in probing depth and a gain in clinical attachment were observed. Conventional radiographs and cone-beam computerized tomographs showed hard tissue improvement. Favorable clinical results were obtained with reimplantation with applied EMD, combined with regenerative therapies, for treating a tooth with severe periodontal involvement. PMID:18351207

  14. Evaluation of Reasons of Permanent Teeth Extraction in Iranian People (2009

    Directory of Open Access Journals (Sweden)

    Kakoei S.

    2012-02-01

    Full Text Available Statement of Problem: Everyday, many people lose their teeth because of various reasons. Knowing the reasons of tooth extraction would help officials to make decisions for helping patients saving their teeth.Purpose: The aim of this study was to investigate the reasons of teeth extraction in dental clinics and some private offices in the city of Kerman in November 2009- February 2010.Materials and Method: In this cross-sectional study, the reasons of teeth extraction in 2076 teeth from 1500 patients selected by simple sampling from Kerman dental clinics were evaluated. Personal data such as gender, age, educational level, occupation, and family size as well as the main reason of tooth extraction (decay, periodontal diseases, prosthesis, tooth impaction, orthodontic reasons, and patient’s request and the type of tooth were collected by a checklist. Data were analyzed in SPSS, version 11.5 using ?² test.Results: The two main reasons of tooth extraction were dental caries (43.6% and patient request (30.6%, respectively. Overall, the first and third molars of the lower jaw were the most commonly extracted teeth. There was a significant relationship between gender and tooth extraction because of caries and orthodontic reasons ( p <0.0001. Meanwhile, the patients’ age had a significant relationship with most teeth extraction reasons ( p <0.0001. Except for patient’s request, educational level had a significant impact on other teeth extraction reasons ( p <0.0001. Conclusion: According to the results of this study, the most common reasons of tooth extraction were dental caries and patient request despite their restorability. Preventive programs and routine dental examination are recommended.

  15. Trace Elements in Human Tooth Enamel

    International Nuclear Information System (INIS)

    The trace elements are considered to play a role in the resistance of teeth to dental caries. The exact mechanism by which they act has not yet been fully established. Estimations of trace elements have been undertaken in sound human teeth. By means of activation analysis it has been possible to determine trace element concentrations in different layers of enamel in the same tooth. The concentrations of the following elements have been determined: arsenic, antimony, copper, zinc, manganese, mercury, molybdenum and vanadium. The distribution of trace elements in enamel varies from those with a narrow range, such as manganese, to those with a broad range, such as antimony. The elements present in the broad range are considered to be non-essential and their presence is thought to result from a chance incorporation into the enamel. Those in the narrow range appear to be essential trace elements and are present in amounts which do not vary unduly from other body tissues. Only manganese and zinc were found in higher concentrations in the surface layer of enamel compared with the inner layers. The importance of the concentration of trace elements on this surface layer of enamel is emphasized as this layer is the site of the first attack by the carious process. (author)

  16. Mechanics of microwear traces in tooth enamel.

    Science.gov (United States)

    Borrero-Lopez, Oscar; Pajares, Antonia; Constantino, Paul J; Lawn, Brian R

    2015-03-01

    It is hypothesized that microwear traces in natural tooth enamel can be simulated and quantified using microindentation mechanics. Microcontacts associated with particulates in the oral wear medium are modeled as sharp indenters with fixed semi-apical angle. Distinction is made between markings from static contacts (pits) and translational contacts (scratches). Relations for the forces required to produce contacts of given dimensions are derived, with particle angularity and compliance specifically taken into account so as to distinguish between different abrasives in food sources. Images of patterns made on human enamel with sharp indenters in axial and sliding loading are correlated with theoretical predictions. Special attention is given to threshold conditions for transition from a microplasticity to a microcracking mode, corresponding to mild and severe wear domains. It is demonstrated that the typical microwear trace is generated at loads on the order of 1N - i.e. much less than the forces exerted in normal biting - attesting to the susceptibility of teeth to wear in everyday mastication, especially in diets with sharp, hard and large inclusive intrinsic or extraneous particulates. PMID:25484336

  17. Effects of ion-releasing tooth-coating material on demineralization of bovine tooth enamel.

    Science.gov (United States)

    Kawasaki, Koji; Kambara, Masaki

    2014-01-01

    We compared the effect of a novel ion-releasing tooth-coating material that contained S-PRG (surface-reaction type prereacted glass-ionomer) filler to that of non-S-PRG filler and nail varnish on the demineralization of bovine enamel subsurface lesions. The demineralization process of bovine enamel was examined using quantitative light-induced fluorescence (QLF) and electron probe microanalyzer (EPMA) measurement. Ion concentrations in demineralizing solution were measured using inductively coupled plasma atomic (ICP) emission spectrometry and an ion electrode. The nail varnish group and the non-S-PRG filler group showed linear demineralization. Although the nail varnish group and the non-S-PRG filler group showed linear demineralization, the S-PRG filler group did not. Further, plane-scanning by EPMA analysis in the S-PRG filler group showed no changes in Ca ion distribution, and F ions showed peak levels on the surface of enamel specimens. Most ions in the demineralizing solution were present at higher concentrations in the S-PRG filler group than in the other two groups. In conclusion, only the S-PRG filler-containing tooth-coating material released ions and inhibited demineralization around the coating. PMID:24578706

  18. Asymmetric extractions in orthodontics

    Scientific Electronic Library Online (English)

    Camilo Aquino, Melgaço; Mônica Tirre de Souza, Araújo.

    2012-04-01

    Full Text Available INTRODUCTION: Extraction decisions are extremely important in during treatment planning. In addition to the extraction decision orthodontists have to choose what tooth should be extracted for the best solution of the problem and the esthetic/functional benefit of the patient. OBJECTIVE: This article [...] aims at reviewing the literature relating the advantages, disadvantages and clinical implications of asymmetric extractions to orthodontics. METHODS: Keywords were selected in English and Portuguese and the EndNote 9 program was used for data base search in PubMed, Web of Science (WSc) and LILACS. The selected articles were case reports, original articles and prospective or retrospective case-control studies concerning asymmetrical extractions of permanent teeth for the treatment of malocclusions. CONCLUSION: According to the literature reviewed asymmetric extractions can make some specific treatment mechanics easier. Cases finished with first permanent molars in Class II or III relationship in one or both sides seem not to cause esthetic or functional problems. However, diagnosis knowledge and mechanics control are essential for treatment success.

  19. Tooth structure and fracture strength of cavities

    Scientific Electronic Library Online (English)

    José, Mondelli; Fábio, Sene; Renata Pereira, Ramos; Ana Raquel, Benetti.

    Full Text Available O objetivo deste estudo foi avaliar, in vitro, a perda de estrutura dentária após o preparo cavitário para restaurações diretas e indiretas e sua relação com a resistência à fratura do dente. 60 pré-molares superiores humanos foram divididos em 6 grupos (n=10). Cavidades MOD para resina composta dir [...] eta (Grupos I, II e III) e cavidades "inlay" (Grupos IV, V e VI) foram preparadas mantendo dimensões padronizadas. A extensão vestíbulo-lingual da caixa oclusal foi estabelecida em 1/4 (Grupos I e IV), 1/3 (Grupos II e V) ou 1/2 (Grupos III e VI) da distância intercuspídea. Os dentes foram pesados, em uma balança de precisão, antes e após o preparo cavitário para aferir a perda de massa dentária. Os dentes preparados foram submetidos à força de compressão para determinar a resistência à fratura em uma máquina universal de ensaios sob uma velocidade de 0.5 mm/min. Os dados foram submetidos à análise de variância a dois critérios e ao teste de Tukey (alfa = 0.05). As cavidades do tipo "1/4-inlay" apresentaram maior percentual de perda de massa (9.71%) em relação às cavidades para resina composta com mesma extensão (7.07%). As cavidades do tipo "1/3-inlay" também apresentaram maior percentual de perda de massa (13.91%) quando comparada às cavidades para resina composta com a mesma extensão (10.02%). As cavidades do tipo "1/2-inlay" apresentaram 21.34% de perda de massa, enquanto as cavidades com extensão de 1/2 para resina composta apresentaram uma perda de 16.19%. As médias de resistência à fratura (em kgf) foram: GI = 187.65; GII = 143.62; GIII = 74.10; GIV = 164.22; GV = 101.92; GVI = 50.35. Diferenças estatisticamente significantes (p Abstract in english This study evaluated, in vitro, the loss of tooth substance after cavity preparation for direct and indirect restorations and its relationship with fracture strength of the prepared teeth. Sixty sound human maxillary first premolars were assigned to 6 groups (n=10). MOD direct composite cavities (Gr [...] oups I, II and III) and indirect inlay cavities (Groups IV, V and VI) were prepared maintaining standardized dimensions: 2-mm deep pulpal floors, 1.5-mm wide gingival walls and 2-mm high axial walls. Buccolingual width of the occlusal box was established at 1/4 (Groups I and IV), 1/3 (Groups II and V) or 1/2 (Groups III and VI) of the intercuspal distance. Teeth were weighed (digital balance accurate to 0.001 g) before and after preparation to record tooth substance mass lost during cavity preparation. The prepared teeth were submitted to occlusal loading to determine their fracture strength using a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed by two-way ANOVA and Tukey test (alpha= 0.05). 1/4-inlay cavities had higher percent mean mass loss (9.71%) than composite resin cavities with the same width (7.07%). 1/3-inlay preparations also produced higher percent mean mass loss (13.91%) than composite resin preparations with the same width (10.02%). 1/2-inlay cavities had 21.34% of mass loss versus 16.19% for the 1/2-composite resin cavities. Fracture strength means (in kgf) were: GI = 187.65; GII = 143.62; GIII = 74.10; GIV = 164.22; GV = 101.92; GVI = 50.35. Statistically significant difference (p

  20. Amery Ice Shelf's 'Loose Tooth' Gets Looser

    Science.gov (United States)

    2002-01-01

    The Amery Ice Shelf is an important dynamic system responsible for draining about 16% of the grounded East Antarctic ice sheet through only 2% of its coastline. Most of the mass input to the system occurs from the Lambert and several other glaciers. Mass loss from the system occurs through basal melting and iceberg calving. These images from the Multi-angle Imaging SpectroRadiometer (MISR) portray the ice shelf front on October 6, 2001 (top) and September 29, 2002 (bottom), and illustrate changes that took place over the year elapsed between the two views.Two longitudinal rifts, oriented roughly parallel to the direction of ice flow and measuring about 25 and 15 kilometers in length, are apparent near the seaward edge of the ice shelf. Between them, a transverse fracture extends eastward from the base of the western rift. This rift system is colloquially named the Amery 'loose tooth.' Over the course of the one-year interval between these two MISR images, the ice front has advanced approximately 1.6 - 1.7 kilometers, and the transverse fracture and a three-way fissure at the juncture of the rifts have widened. When the transverse fracture eventually reaches the eastern rift, a large iceberg (25 kilometers x 25 kilometers) will be released.These false-color multi-angle composites combine red-band data from MISR's 60o forward, nadir, and 60o aftward viewing cameras, displayed as red, green and blue, respectively. Different colors represent angular reflectance variations. Since generally smooth surfaces predominantly forward-scatter sunlight, these appear in shades of blue. Rough surfaces tend to backward-scatter sunlight, and these appear in shades of red or orange. Low clouds appear bright purple, since they exhibit both forward and backward-scattering. Using this technique, textural variations among ice types are revealed, and clouds can be easily distinguished from ice. Illumination conditions on the two dates are nearly identical.Understanding the 'normal' frequency of calving events from a particular ice shelf is necessary before it can be determined whether calving rates are changing. As part of an effort to determine the normal rate of ice flow and iceberg calving events, the Amery Ice Shelf front has been monitored by various remote sensing instruments for many years. The Amery Ice Shelf is currently considered to be about two-thirds of the way through a calving cycle. The last major calving event occurred in the early 1960's, when a massive iceberg (measuring about 140 kilometers x 70 kilometers) was released.The Amery 'loose tooth' is the subject of a joint field experiment during the 2002 austral summer, partially funded by NASA and undertaken by the Scripps Institution of Oceanography and the Australian Antarctic Division. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbits 9579 and 14807. The panels cover an area of about 204 kilometers x 110 kilometers, and utilize data from blocks 146 to 147 within World Reference System-2 paths 127 and 128, respectively. Data from the two orbital paths have been remapped to identical polar projections, and were cropped to include the same geographic area.MISR was built and is managed by NASA's Jet Propulsion Laboratory,Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center,Greenbelt, MD. JPL is a division of the California Institute of Technology.

  1. The challenges of treating a fused tooth

    Scientific Electronic Library Online (English)

    Flares, Baratto-Filho; Denise Piotto, Leonardi; Bruno Monguilhott, Crozeta; Samantha Pugsley, Baratto; Edson Alves, Campos; Flavia Sens Fagundes, Tomazinho; Tatiana Miranda, Deliberador.

    Full Text Available Este caso descreve o tratamento multidisciplinar de um incisivo lateral superior permanente fusionado a um dente supranumerário, ambos apresentando necrose pulpar e lesão periapical. Paciente compareceu ao consultório se queixando de dor, edema e mobilidade do incisivo lateral superior. O preparo en [...] dodôntico foi realizado no sentido coroa-ápice e foi colocada pasta de hidróxido de cálcio como medicação intra-canal por 15 dias. A seguir, a obturação foi realizada pela termoplastificação da guta-percha. Após 18 meses, foram realizados exames clínicos e radiográficos indicando ausência de dor e edema. Dois anos após o tratamento endodôntico, o paciente retornou para o tratamento periodontal e estético. Nove meses depois, foi realizada tomografia computadorizada e observou-se presença de defeito periodontal e lesão periapical. Foi então indicada e planejada a cirurgia paraendodôntica. O dente supranumerário foi removido e a área de comunicação com o canal radicular do incisivo lateral foi preenchida; a loja cirúrgica foi preenchida com vidro bioativo e osso orgânico bovino desmineralizado. O tecido patológico da lesão periapical foi submetido à análise histopatológica sendo diagnosticado como cisto periapical. Um ano após a cirurgia parendodôntica, uma nova tomografia computadorizada mostrou neoformação óssea na região periapical do dente em questão. Doi anos após a cirurgia, a restauração foi trocada devido à motivos estéticos e uma radiografia periapical mostrou sucesso do tratamento (5 anos após o tratamento inicial). Um correto diagnóstico e plano de tratamento multidisciplinar é essencial para o sucesso do tratamento de dentes fusionados à dentes supranumerários. Abstract in english This paper describes and discusses the multidisciplinary treatment involving a permanent maxillary lateral incisor fused to a supernumerary tooth, both presenting pulp necrosis and periapical lesion. A 15-year-old male patient sought treatment complaining of pain, swelling and mobility on the maxill [...] ary right lateral incisor. After clinical and radiographic examination, root canal preparation was performed according to the crown-down technique and a calcium hydroxide dressing was placed for 15 days. The patient returned and the definitive endodontic filling was done with thermomechanical compaction of gutta-percha and sealer. After 18 months, clinical and radiographic examinations were carried out and no pain or swelling was reported. Two years after endodontic treatment, the patient returned for periodontal and cosmetic treatments. Nine months later, a cone-beam computed tomography (CBCT) revealed that the previously detected periodontal defect and periapical lesion were persistent. Apical endodontic surgery was indicated. The supernumerary tooth was removed, the communicating distal surface was filled and the surgical site received bioactive glass and demineralized bovine organic bone. The pathological tissue was submitted to histopathological examination and the diagnosis was periapical cyst. One year after the apical endodontic surgery, CBCT showed bone formation at maxillary lateral incisor apical area. Two years after the surgery, the restoration was replaced due to aesthetic reasons and periapical radiograph showed success after 5 years of treatment. A correct diagnosis and establishment of an adequate treatment plan resulted in a successful management of the case.

  2. Effect of several tooth-colored restorative materials on reinforcement of unsupported enamel

    Directory of Open Access Journals (Sweden)

    Mohammadreza Malekipour

    2012-01-01

    Full Text Available Introduction: Adhesive restorations properly transmit and distribute functional stresses at the bonding interface to tooth structures and have the potential to reinforce remaining weakened tooth structures after removal of extensive carious lesions. This study evaluated the effect of a number of adhesive restorative materials on reinforcing unsupported enamel. Materials and Methods: Seventy-five extracted sound maxillary premolars collected over 3 months and stored in 0.2% thymol solution received MOD cavities; the lingual cusps were reduced up to the pulp level. The specimens were divided into five groups (n=15. In group 1 (the positive control, dentinal tissue of the buccal wall was preserved. In other groups the buccal dentin was completely removed. In group 2 (the negative control, no restorative material was used to replace the lost dentin. The removed buccal dentin was replaced with composite resin, flowable composite resin and glass-ionomer in groups 3, 4 and 5, respectively. After thermocycling, the specimens were tested in an Instron universal testing machine. Data were analyzed with ANOVA and LSD test (a < 0.05. Results: The mean and standard deviations of fracture loads of the five groups were 122.97 ± 15.11, 44.71 ± 14.23, 78.32±17.58, 81.17 ± 19.53, and 85.33 ± 22.07 Newtons, respectively. One-way ANOVA revealed significant differences between the groups (p value = 0.00. There were significant differences in fracture loads between groups 1 and 2 and others (p value = 0.00. The difference in fracture loads between group 3 and 4 (p value = 0.678, groups 3 and 5 (p value = 0.344, and groups 4 and 5 (p value = 0.589 were not significant. Conclusion: It can be concluded that the three types of adhesive restorative materials in this study can reinforce unsupported enamel to a certain degree. Key words: Composite resin, Dental adhesives, Reinforcement, Tooth enamel.

  3. Success Rate of Formocresol Pulpotomy versus Mineral Trioxide Aggregate in Human Primary Molar Tooth

    Directory of Open Access Journals (Sweden)

    S E Jabbarifar

    2004-12-01

    Full Text Available Background: In spite of long time and broad use of formaldehyde derivates (Fixation agent in primary tooth pulp treatment, There is some concerns about these derivates such as variability, inconsistency success rate, mutagenicity, cytotoxicity, alergenicity, and some other potential health hazards of them. Therefore other alternative pulpotomy procedures like Bioactive glass (BAG, Glutaraldehyde (2%, Hydroxyappetite (HA, Bone dried freezed (BDF, ferric sulfate (15%, laser, Electrosurgery (ES, Bone Morphogenic proteins (BMP, recombinant protein-1 (RP1, and Mineral Trioxide Aggregate (MTA have been compared. The purpose of this clinical trial is to assess radiographic and clinical success rate of Formocresol (FC pulpotomy in compare with MTA in human primary molar teeth. Methods: 64 molars were pulpotomized equally and randomly with mineral trioxide Aggregate and Formocresol. Prior to trial, we defined a case as failure, when one or more of the events such as external root resorption, internal root resorption, periapical and furca lucency, pain, swelling, mobility, dental abscess, or early extraction appeared. Every treated tooth was defined as successful, if any noted evident was not shown. Results: Totally, 60 teeth treatment (92.2 percent were successful and 7.8 percent were failed. Failure and success rates for MTA group were 6.3 and 93.7 percent, respectively. Failure and success rates in FC group were 8.4 and 90.2 percent respectively. The difference between MTA and FC treatment methods was not significant (Fisher Exact test. Conclusion: Findings of this study show that mineral trioxide aggregate can be an alternative procedure for FC pulpotomy of primary tooth. Keywords: Mineral trioxide aggregate, formocresol, pulpotomy, success and failure rate.

  4. Effect of Multiple Adhesive Coating on Microshear Bond Strength to Primary Tooth Dentin

    Directory of Open Access Journals (Sweden)

    Beheshteh Malekafzali Malekafzali

    2013-01-01

    Full Text Available Objective: Multiple adhesive coating is a controversial topic, especially in primary dentition that should be clarified. We evaluated the effect of multiple consecutive adhesive resin coatings on the microshear bond strength (µSBS of composite resin to primary tooth dentin utilizing a filled (Adper Single Bond Plus and an unfilled (Adper Single Bond adhesive resin.Materials and Methods: Thirty extracted primary canines were randomly allocated into two groups based on the adhesive used. Dentin occlusal surfaces were exposed and further polished on 400, 600 and 800-grit silicon-carbide paper. The surfaces were divided into two halves in the labial-lingual orientation. After etching, the adhesives were used either in double coats, or four coats on the halves of the same tooth followed by air evaporation for each layer and finally light curing. Cylinders of composite were bonded to the dentin surfaces. After 24 h shear bond testing was evaluated by Bisco tensile tester. ANOVA, Student t test and paired t test were used for statistical analysis.Results: The mean (standard deviation for double coats or four coats in single bond were 31.99 (2.94 and 30.25 (2.69, while they were 29.18 (3.35 and 31.26 (2.07 in single bond plus, respectively. No significant differences were found between the double coated specimens and those receiving four coatings with both adhesives (p>0.05. Micro SBS values of Single Bond double coated specimens were significantly higher than Single Bond Plus (p=0.02. In four-coated specimens, there were no significant differences between Single Bond and Single Bond Plus (p=0.26.Conclusion: Applying four coats of adhesive did not improve the µSBS to primary tooth dentin.

  5. Tooth regeneration: a revolution in stomatology and evolution in regenerative medicine

    OpenAIRE

    Yildirim, Sibel; Fu, Susan Y.; Kim, Keith; Zhou, Hong; Lee, Chang Hun; Li, Ang; Kim, Sahng Gyoon; WANG Shuang; Mao, Jeremy J.

    2011-01-01

    A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated? Can adult stem cells be orchestrated to regenerate tooth structures such as the enamel, dentin, cementum and dental pulp, or even an entire tooth? If not, what are the therapeutically viable sources of stem cells for tooth regeneration? Do stem cells necessarily need to be taken out of the body, and man...

  6. Detecting Gear Tooth Fatigue Cracks in Advance of Complete Fracture

    Science.gov (United States)

    Zakrajsek, James J.; Lewicki, David G.

    1996-01-01

    Results of using vibration-based methods to detect gear tooth fatigue cracks are presented. An experimental test rig was used to fail a number of spur gear specimens through bending fatigue. The gear tooth fatigue crack in each test was initiated through a small notch in the fillet area of a tooth on the gear. The primary purpose of these tests was to verify analytical predictions of fatigue crack propagation direction and rate as a function of gear rim thickness. The vibration signal from a total of three tests was monitored and recorded for gear fault detection research. The damage consisted of complete rim fracture on the two thin rim gears and single tooth fracture on the standard full rim test gear. Vibration-based fault detection methods were applied to the vibration signal both on-line and after the tests were completed. The objectives of this effort were to identify methods capable of detecting the fatigue crack and to determine how far in advance of total failure positive detection was given. Results show that the fault detection methods failed to respond to the fatigue crack prior to complete rim fracture in the thin rim gear tests. In the standard full rim gear test all of the methods responded to the fatigue crack in advance of tooth fracture; however, only three of the methods responded to the fatigue crack in the early stages of crack propagation.

  7. Efficient transport of droplet sandwiched between saw-tooth plates.

    Science.gov (United States)

    Wang, Liya; Wu, Hengan; Wang, Fengchao

    2016-01-15

    The transport of droplet sandwiched between smooth and saw-tooth plates was investigated using molecular dynamics method. The repeated opening and closing of the plates result in sequential stretching and squeezing of the droplet, which provide the driving force. The asymmetrical saw tooth obstructs the backward motion of the droplet, and gives rise to a net forward displacement of the droplet in every opening and closing cycle. This unidirectional motion facilitates the efficient droplet transport, which is referred to as the ratchet-like effect in this work. Our simulations also reveal that the influence of the surface wettability on the droplet transport is different for saw-tooth and smooth plates. Droplet transport efficiency exhibits monotonic decrease with the increase of the solid-liquid interactions for saw-tooth plates. While for smooth plates, unidirectional droplet movement was only observed for certain solid-liquid interactions. Taken together these simulation results and theoretical analysis, we demonstrate that hydrophobic saw-tooth plates can improve the transport efficiency significantly. These findings not only enhance our understanding of the droplet transport from atomistic scale, but also are beneficial to practical applications in designing of micro- and nano-fluidic systems. PMID:26473277

  8. Properties of goat tooth enamel electron spin resonance dosimetry

    International Nuclear Information System (INIS)

    Objective: To study the properties of goat tooth enamel electron spin resonance (ESR) dosimetry. Methods: Tooth enamel samples of goats were achieved by combined mechanical and chemical treatment at the ages of l, 2, 3, 5, and 6 years, respectively and 9 enamel samples of adult molar were obtained. These enamel samples were exposed to 137Cs ?-rays at the cumulative doses of 0, 0.5, 1.0, 2.0, and 5.0 Gy, respectively. ESR spectra Was measured before and after exposure. Results: The background signal of goat tooth samples was 21.5, significantly lower than that of the adult molar samples (39.5). The dosimetric signal intensity of the goat enamel increased with the radiation dose in a linear manner just as that of the human molars. The average radiation sensitivity of the goat tooth samples was (34.3±1.9)/Gy, close to that of the human tooth samples. Conclusions: Goat teeth can be used for retrospective radiation dose reconstruction when human teeth are unavailable, in order to provide scientific data for dose reconstruction accurately. (authors)

  9. In Vitro Color Change of Three Dental Veneering Resins in Tea, Coffee and Tamarind Extracts

    Directory of Open Access Journals (Sweden)

    S. Muttagi

    2011-09-01

    Full Text Available Objective: To study the in vitro color changes of three dental resin veneering materials when immersed in tea, coffee and tamarind extracts.Materials and Methods: The color changes of heat polymerized tooth colored acrylic resin (Stellondetrey, B, F14, DPI Dental products of India Ltd, Mumbai, auto polymerized tooth colored acrylic resin (DPI, B, QV5, DPI Dental products of India Ltd, Mumbai andlight polymerized resin composite (Herculite XRV, Enamel A2, part no. 22860, lot no. 910437, Kerr Corporation, West Collins Avenue, Orange, CA, USA when immersed in water extracts of tea (Tata Tea Ltd. Bangalore, India, coffee (Tata Coffee Ltd. Coorg, Indiaand tamarind were evaluated using computer vision systems. The color images were recorded in R (red, G (green and B (blue form and converted into H (hue, S (saturationand V (value.Results: Significant color change occurred for auto polymerized tooth colored acrylic resin in tamarind extract, for heat polymerized tooth colored acrylic resin in tea extract andfor light polymerized resin composite in coffee extract. Auto polymerized tooth colored acrylic resin samples showed an overall higher color change. However, for all the material samples coffee extract produced more color change.Conclusion: These results suggest that the color stability of the resins is influenced by the presence of secondary metabolites such as tartaric acid, tannins, caffeine, saponins and phenols in tamarind, tea and coffee extracts.

  10. Electron microscopy analysis of different orthodontic brackets and their adhesion to the tooth enamel.

    Science.gov (United States)

    Ciocan, Delia Ioana; Stanciu, Drago?; Popescu, Manuela Anca; Miculescu, Florin; Plotog, Ioan; V?rzaru, Gauden?iu; Ciocan, Lucian Toma

    2014-01-01

    This study proposed to evaluate the surface morphology of different types of orthodontic brackets and the characteristics of their adhesion to the tooth enamel. There have been taken into study six metallic, five ceramic and one polymeric bracket from different brands (Ormco, Lancer, Leone, Damon, 3M, Ultradent, American Orthodontics, Rocky Mountain). The surface base of the each bracket it have been ESEM analyzed using scanning electron microscope Phillips XL-30 ESEM. There have been investigated several parameters that have a potential influence of the bracket-bonding agent interface joint: chemical composition, roughness, surface morphology and wideness. After ESEM analysis, the same metallic and ceramic brackets have been afterwards collated on extracted teeth and subjected to mechanical tests. After the mechanical testing, the samples were once again ESEM investigated. All fractures occurred in the area of the adhesive system, recording adhesive fractures of the tooth-composite resin and composite-bracket, cohesive fractures and both. The metallic brackets surfaces that are optima for a good adhesion is that of a mesh sand blasted and acid etched. From the esthetic brackets, the ceramic ones are superior to polymeric ones regarding bonding to teeth. PMID:25178330

  11. Expression of RANKL mRNA during Root Resorption Induced by Orthodontic Tooth Movement in Rats

    Directory of Open Access Journals (Sweden)

    Massoud Seifi

    2009-01-01

    Full Text Available Objective: Receptor activator for nuclear factor kappa B ligand (RANKL, which is alsocalled osteoclast differentiation factor, is an important regulatory factor in osteoclastmaturation. Knowledge of bone and cementum similarities and RANKL role in bone resorptionsuggests the possibility of a role for this protein in root resorption induced by orthodontictooth movement. The aim of this study is to examine the expression of RANKLmRNA during root resorption induced by orthodontic tooth movement in rats.Materials and Methods: In order to move maxillary right first molars mesially fixed Ni-Ticlosed coil springs (Dentaurum®-Germany were tightened to the teeth. Sample consistedof 20 male seven week old Wistar rats. For each animal, the contralateral tooth was usedas, an internal control. At day 21 the rats were sacrificed. Tissues from 10 rats were embeddedin paraffin for histologic examination. Scratched material from resorptive lacunaeon mesial sides of the roots of the other ten rats was used for extracting mRNA by RTPCR.Results: The histologic sections, analyzed histomorphometrically, showed a significantincrease in root resorption in the case group as compared to the control (p<0.001.Densitometric studies of RANKL mRNA expression band on gel electrophoresis showedsignificantly increased RANKL expression in the resorptive lacunae of the case group(p<0.001.Conclusion: This observation indicates increased RANKL

  12. Assessing the application of tooth cementum annulation relative to macroscopic aging techniques in an archeological sample.

    Science.gov (United States)

    Gauthier, J; Schutkowski, H

    2013-02-01

    The analysis of human skeletal remains is frequently impeded by the lack of adequately preserved morphological markers on which to base age estimation, particularly in archeological contexts. Therefore, histological methods such as tooth cementum annulation analysis can be useful for extracting reliable age estimates from poorly preserved skeletons, if they produce results corresponding to morphologically based, multifactorial assessments. In order to test this presumption, this study compares tooth cementum annulation (TCA) with macroscopic age estimation results incorporating the Brooks-Suchey pubic symphysis and the Buckberry-Chamberlain revised auricular surface methods, as well as Brothwell's guidelines for analyzing dental attrition. Undecalcified, polished, and unstained transverse thin sections viewed using standard light microscopy, with decentered phase contrast microscopy in cases of poorly delineated cementum annulations, were used for TCA counts. Age estimates were applied independently on the late medieval archeological Box Lane cemetery assemblage from Pontefract, England, to analyze their measure of correspondence and to assess whether data produced by a single histological technique are comparable to information pooled from multiple morphological age markers. Spearman's rank correlation tests resulted in a significant association between TCA and morphological age estimates. Further studies using larger samples of known age material would help to improve our understanding of TCA age estimation performance relative to macroscopic age assessment as well as continued refinement and standardization of cementum sectioning, which is suggested to impact annulation visibility. PMID:23218650

  13. Tooth allotransplantation: Evaluation and report of 15 cases

    Directory of Open Access Journals (Sweden)

    AH. Fakhraie

    1994-07-01

    Full Text Available Tooth Transplantation from one individual to another is a method of replacing missing teeth. This method can be used as an applicable clinical treatment technique due to its numerous advantages .There are different methods of tooth transplantation. Among those, the safest and healthiest is transplantation of non-vital teeth or allostatic transplantation. In this method, the risk of antigenicity in recipient is low and also there is no risk of transmission of infectious diseases such as Hepatities or AIDS. The aim of this study was to evaluate the clinical results of tooth allotransplantation. Current study was conducted on 15 non-vital transplanted teeth within 18 months follow-up. Only one case of rejection was observed which was a Traumatic Rejection. Replacement resorption was found in all the cases while inflammatory resorption was recorded in only two cases. WBC Cross Match Test with pannel cell results were negative in all the cases.

  14. Mechanochemical control of mesenchymal condensation and embryonic tooth organ formation.

    Science.gov (United States)

    Mammoto, Tadanori; Mammoto, Akiko; Torisawa, Yu-suke; Tat, Tracy; Gibbs, Ashley; Derda, Ratmir; Mannix, Robert; de Bruijn, Marlieke; Yung, Chong Wing; Huh, Dongeun; Ingber, Donald E

    2011-10-18

    Mesenchymal condensation is critical for organogenesis, yet little is known about how this process is controlled. Here we show that Fgf8 and Sema3f, produced by early dental epithelium, respectively, attract and repulse mesenchymal cells, which cause them to pack tightly together during mouse tooth development. Resulting mechanical compaction-induced changes in cell shape induce odontogenic transcription factors (Pax9, Msx1) and a chemical cue (BMP4), and mechanical compression of mesenchyme is sufficient to induce tooth-specific cell fate switching. The inductive effects of cell compaction are mediated by suppression of the mechanical signaling molecule RhoA, and its overexpression prevents odontogenic induction. Thus, the mesenchymal condensation that drives tooth formation is induced by antagonistic epithelial morphogens that manifest their pattern-generating actions mechanically via changes in mesenchymal cell shape and altered mechanotransduction. PMID:21924961

  15. Patient Discomfort Following Single-Tooth Implant Placement : A Randomized Controlled Trial of Immediate vs. Conventional Tooth Restoration

    DEFF Research Database (Denmark)

    Spin-Neto, Rubens; Pontes, Ana Emília Farias

    2014-01-01

    Aims: Evaluate postoperative discomfort (pain, bleeding and swelling) in single-tooth implant patients submitted to immediate or conventional tooth restoration together with assessment of treatment time. Methods: Twenty-four patients who received single-tooth maxillary dental implants were randomly assigned to an IR (Immediate Restoration) or CR (Conventional Restoration) group. In IR, an implant was inserted and a provisional tooth crown was delivered within the same session, while in CR it was delivered three months after implantation. Pain (first three days), bleeding (first day) and swelling (first seven days) were assessed using a questionnaire with Visual Analogue Scales (VAS). Results: Treatment time was longer for IR than for CR (57 ± 14 and 33 ± 8 min, respectively; p<0.0001). Mean VAS scores for pain, bleeding, and swelling were low for both groups at the first postoperative day. VAS scores for pain and swelling decreased continuously over the time period in both groups. Conclusions: The longer treatment time in IR didn't increase patients' perception of pain, bleeding and swelling, compared to CR. The impact of immediate tooth restoration on patients' esthetic outcome should be further considered.

  16. Root canal treatment of mandibular second premolar tooth with taurodontism

    Directory of Open Access Journals (Sweden)

    Vujaškovi? Mirjana

    2008-01-01

    Full Text Available INTRODUCTION Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. CASE OUTLINE The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. CONCLUSION Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.

  17. Generation of gear tooth surfaces by application of CNC machines

    Science.gov (United States)

    Litvin, F. L.; Chen, N. X.

    1994-01-01

    This study will demonstrate the importance of application of computer numerically controlled (CNC) machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis (TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm gear drives with cylindrical worms, etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment. The report will describe the following topics: description of kinematics of CNC machines with six degrees of freedom that can be applied for generation of gear tooth surfaces with new topology. A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines is described. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. Execution of motions of the CNC machine is also described. The solution to this problem can be applied as well for the transfer of machine tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on these topics of differential geometry is provided as well.

  18. Dosimetric studies of gamma irradiated tooth enamel using XRD analyses

    International Nuclear Information System (INIS)

    The structure of bovine teeth enamel before and after gamma irradiation was investigated via X-ray diffraction (XRD) analyses. The irradiation doses were conducted at the values ranging from 5 Gy to 5 kGy, respectively. Tooth enamel contains, mainly, crystals of hexagonal form. The radiation induced creation of carbonated free radicals and their concentration grew in a proportional manner to the irradiation dose resulting in a decrease in the crystallinity. In addition, the unit cell volume increases as the gamma radiation dose increases due to the increasing in a- and c-axes. Also, the strain increases giving rise to the disordering in tooth enamel samples as gamma dose increases

  19. Anomalies of tooth formation in hypohidrotic ectodermal dysplasia

    DEFF Research Database (Denmark)

    Lexner, Michala Oron; Bardow, Allan

    2007-01-01

    The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous females, enabling an earlier diagnosis, and therefore, better treatment and genetic counselling.

  20. Crystal structure of human tooth enamel studied by neutron diffraction

    Science.gov (United States)

    Ouladdiaf, Bachir; Rodriguez-Carvajal, Juan; Goutaudier, Christelle; Ouladdiaf, Selma; Grosgogeat, Brigitte; Pradelle, Nelly; Colon, Pierre

    2015-02-01

    Crystal structure of human tooth enamel was investigated using high-resolution neutron powder diffraction. Excellent agreement between observed and refined patterns is obtained, using the hexagonal hydroxyapatite model for the tooth enamel, where a large hydroxyl deficiency ˜70% is found in the 4e site. Rietveld refinements method combined with the difference Fourier maps have revealed, however, that the hydroxyl ions are not only disordered along the c-axis but also within the basal plane. Additional H ions located at the 6h site and forming HPO42- anions were found.

  1. Turner's tooth with unique radiographic presentation: a case report.

    Science.gov (United States)

    Lakshman, Anusha Rangare; Kanneppady, Sham Kishor; Castelino, Renita Lorina

    2014-01-01

    Hypoplasia--the result of a disruption in the enamel matrix formation process--causes a defect in the quality and thickness of enamel. Enamel formation is a complex and highly regulated process. Enamel defects have been associated with a broad spectrum of etiologies, including genetic, epigenetic, systemic, local, and environmental factors. An enamel defect in the permanent teeth caused by periapical inflammatory disease in the overlying primary tooth is referred to as Turner's tooth (also known as Turner's hypoplasia). This article presents a case of Turner's hypoplasia of the first mandibular premolar, with an unusual radiographic presentation. PMID:25184717

  2. Primary Cilia Integrate Hedgehog and Wnt Signaling during Tooth Development

    OpenAIRE

    Liu, B; Chen, S.; Cheng, D; Jing, W; Helms, J.A.

    2014-01-01

    Many ciliopathies have clinical features that include tooth malformations but how these defects come about is not clear. Here we show that genetic deletion of the motor protein Kif3a in dental mesenchyme results in an arrest in odontogenesis. Incisors are completely missing, and molars are enlarged in Wnt1Cre+Kif3afl/fl embryos. Although amelogenesis and dentinogenesis initiate in the molar tooth bud, both processes terminate prematurely. We demonstrate that loss of Kif3a in dental mesenchyme...

  3. Delayed Tooth Replantation after Traumatic Avulsion: A Case Report

    OpenAIRE

    Khalilak, Zohreh; Shikholislami, Mahshid; Mohajeri, Ladan

    2008-01-01

    Avulsion is a serious injury which causes damage to dental and supportive tissues, ranging from 1-16 % among dental injuries and it mostly occurs in maxillary incisors. This report presents a case of replantation of a traumatically avulsed central incisor. The left central incisor of an 8 year-old boy with open apex was avulsed and was left in unclean and dry conditions. Tooth was replaced after 270 min and splinted. After 24 hours, tooth was treated endodontically. The calcium hydroxide past...

  4. Spatial distribution of radiation defects in tooth enamel

    International Nuclear Information System (INIS)

    Spatial distribution of radiation defects in tooth enamel is studied through the method of the EPR-tomography. The enamel plates, irradiated by ? rays and electrons with energy of 1.2 and 3.8 MeV, are studied. Decrease in the radiation defects concentration is determined along the direction of radiation action. Distribution of defects in the ?-irradiated plates was uniform. It is shown that the tooth enamel study through the EPR-tomography may be used for determination of the type and energy characteristics of ionizing radiation, effecting living body

  5. Metabolism in tooth enamel and reliability of retrospective dosimetry

    International Nuclear Information System (INIS)

    Most of the radiation centers in tooth enamel and bones are formed by the reactions COOH+??CO-2+H+, and CO2+e-?CO-2. These centers can be easily changed by metabolism and have a low stability in living organisms. The efficiency of CO-2 radical production by irradiation is substantially different for teeth and bones in living rat, dead rat, and teeth and bone removed from rat. It is shown that the suitability of tooth enamel for retrospective dosimetry can be evaluated from the anisotropy of its EPR signals

  6. Tooth enamel sample preparation using alkaline treatment in ESR dosimetry

    International Nuclear Information System (INIS)

    Tooth enamel sample preparation using alkaline treatment was studied and compared with traditional mechanical method in this paper. 20 adult teeth were used. Samples were placed into NaOH solution. This method requires 4-5 weeks and the enamel was separated from dentin. Experimental results show that 8M NaOH was appropriate for separating enamel from dentin and that there is no difference in background signal relative intensity between samples prepared by mechanical and by chemical methods. There is also no difference in radiosensitivity between samples prepared by two methods mentioned above. Dose response curve for tooth enamel samples isolated by 8M NaOH solution was obtained

  7. Restoration of noncarious tooth defects by dentists in The Dental Practice-Based Research Network

    DEFF Research Database (Denmark)

    Nascimento, Marcelle M; Gordan, Valeria V; Qvist, Vibeke; Bader, James D; Rindal, D Brad; Williams, O Dale; Gewartowski, Daniel; Fellows, Jeffrey L; Litaker, Mark S; Gilbert, Gregg H

    2011-01-01

    The authors conducted a study to quantify the reasons for restoring noncarious tooth defects (NCTDs) by dentists in The Dental Practice-Based Research Network (DPBRN) and to assess the tooth, patient and dentist characteristics associated with those reasons.

  8. In vivo PIXE-PIGE study of enhanced retention of fluorine in tooth enamel after laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Demortier, Guy [Department of Physics, University of Namur, 61, rue de Bruxelles, B5000 Namur (Belgium)], E-mail: guy.demortier@tvcablenet.be; Nammour, Samir [Faculty of Medicine, University of Liege, 8, rue Paul Spaak, B-1000 Bruxelles (Belgium)

    2008-05-15

    The presence of fluoride in tooth enamel reduces the solubility of hydroxylapatite by acid attack. Fluoride presence (even at low concentration) in the oral cavity is efficient against caries process. We propose a new approach of the explanation of the increase of fluoride retention in the tooth enamel when low power laser irradiation is applied after the treatment with fluoride gel (fluoridation). External beam PIGE measurements of fluorine on extracted teeth have been made in order to determine the best sequence of the operations. The laser irradiation after fluoride application is more efficient than the reverse procedure. This observation is in agreement with previous observations that the fluorine penetration in the enamel takes place first in the soft organic material present between the polycrystalline (prismatic) structure before being integrated in the crystalline composition of hydroxylapatite in order to produce fluoro-apatite. As those in vitro measurements do not reflect the whole process in the saliva, in vivo PIGE measurements have been also performed. We have demonstrated, by repeating the PIGE measurements (at least five times at various time intervals) that a significant increase of the fluoride retention took place even 18 months after the unique laser treatment. The complete experimental procedure is described: fluoride application, laser irradiation, PIGE measurements with 2.7 MeV protons (repeated measurements at the same place on the same tooth in order to follow the evolution) and safety tests before in vivo analyses.

  9. The Effect of Diode Laser Treatment for Root Canal Disinfection on Fracture Resistance and Micro-hardness of the Tooth

    International Nuclear Information System (INIS)

    This study evaluated the effect of diode laser treatment for root canal disinfection on fracture resistance and micro-hardness of the tooth. Sixty freshly extracted mandibular and maxillary premolars were accessed under coolant then root canals were flared up to apical preparation size 40 MFA coupled with 5.25% NaOCl as an irrigant. Teeth were divided into two groups, control group (group I) and lased group (group II) that was lased by diode laser with average power 2 w through fibrooptic into the canal 2 mm shorter than the apex. Each tooth was embedded in acrylic block, and then subjected to the fracture resistance test. Each root was then sectioned transversely and polished to record dentin Vickers hardness. Data was analysed with student t-test then with linear regression test. The Lased samples presented a significantly higher resistance to fracture than unlased samples. There was no statistically significant differences found between Vickers hardness (HV) of lased and unlased samples and there was no relation between fracture resistance and microhardness. Diode laser (980 nm) treatment had no adverse effect on dentin microhardness, also it increased the fracture resistance of dentin. Diode laser (980 nm) treatment could attain better function ability and maintenance of tooth after endodontic treatment.

  10. Clinical evaluation of postradiation dental extraction

    International Nuclear Information System (INIS)

    Twenty-one patients who had undergone postradiation dental extraction were evaluated clinically. All patients had received irradiation for primary head and neck malignancies at doses ranging from 8 to 60 Gy (mean, 51.6 Gy). Time to dental extraction after irradiation ranged from 8 to 156 months (mean, 57.9 months). Of the 21 patients (80 teeth extracted, including 33 maxillary teeth and 47 mandibular teeth), one had delayed healing after wisdom tooth extraction due to postextraction irradiation. Thus, osteoradionecrosis after dental extraction did not develop. These results suggest that dental extraction after radiation is not contraindicated. To prevent complications, patients who have received radiation and require extractions should be cared for by oral and maxillofacial surgeons in close association with radiation oncologists. (author)

  11. Regeneration of tooth-like hydroxyapatite depended on amelogenin functional section monolayer: a new approach for tooth repair.

    Science.gov (United States)

    Tian, Kun; Peng, Min; Ren, Xiaohua; Liao, Chuhang; Fei, Wei

    2012-08-01

    Tooth defect due to caries, trauma, or acid corrosion are common in mankind. Ceramics, metal and resin were used to repaired tooth defect in the past hundred years, but they cannot instead enamel and dentin in depth in clinic usage for the difference in structure and element. So the formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Now synthesizing a mimicking structure of human enamel using acellular methods has attracted much interest from research groups who have tried using recombinant enamel making proteins like amelogenin, surfactants, to mimic the biomineralization process to restore the enamel layer. Since amelogenin can be used in the assembly of functional nanostructures, we hypothesis that rationally designed ?-sheet-forming peptides that spontaneously form three-dimensional fibrillar scaffolds in response to specific environmental triggers may potentially be used in inducing tooth-like hydroxyapatite crystal ex vivo which important to treatment/prevention of dental caries, via bioactive surface groups. PMID:22564781

  12. Tooth loss patterns in older adults with special needs: a Minnesota cohort

    OpenAIRE

    Chen, Xi; Clark, Jennifer J.

    2011-01-01

    This study was conducted to detail tooth loss patterns in older adults with special needs. A total of 491 elderly subjects with special needs were retrospectively selected and followed during 10/1999-12/2006. Medical, dental, cognitive, and functional assessments were abstracted from dental records and used to predict risk of tooth loss. Tooth loss events were recorded for subjects during follow-up. Chi-squared tests were used to study the association between tooth loss and the selected risk ...

  13. Measurement accuracy and reliability of tooth length on conventional and CBCT reconstructed panoramic radiographs

    Scientific Electronic Library Online (English)

    Carlos, Flores-Mir; Mark R, Rosenblatt; Paul W., Major; Jason P., Carey; Giseon, Heo.

    2014-10-01

    Full Text Available INTRODUÇÃO: este estudo in vivo avaliou a precisão e a confiabilidade de medições do comprimento dentário realizadas em radiografias panorâmicas convencionais e em reconstruções panorâmicas de tomografias computadorizadas de feixe cônico (TCFC), comparando-as com medições feitas com um paquímetro [...] digital, consideradas o padrão-ouro. MÉTODOS: a amostra incluiu indivíduos que já tivessem realizado tanto exames imaginológicos de TCFC quanto radiografias panorâmicas, e cujo tratamento ortodôntico exigisse a extração de pré-molar superior. No total, 48 dentes extraídos, de 26 pacientes, foram mensurados diretamente com paquímetros digitais. As radiografias foram escaneadas e digitalmente avaliadas com a ajuda do software Dolphin 3D. Por meio da análise de variância simples com correção de Bonferroni e Coeficiente de Correlação Intraclasse simples, comparou-se a precisão das medições de comprimento dentário realizadas em reconstruções panorâmicas de TCFC, em radiografias panorâmicas convencionais e com paquímetro digital. RESULTADOS: medições repetidas de comprimento dentário feitas com o paquímetro digital, radiografias panorâmicas e reconstruções panorâmicas de TCFC foram todas consideradas, individualmente, altamente confiáveis. Em comparação ao paquímetro, as medidas obtidas por meio de radiografias panorâmicas convencionais foram, em média, 6,3 ± 2,0mm mais longas, enquanto as medidas obtidas por meio das reconstruções panorâmicas de TCFC foram, em média, 1,7 ± 1,2mm mais curtas. CONCLUSÕES: em comparação com o real comprimento dentário, as radiografias panorâmicas convencionais foram relativamente imprecisas e superestimaram o comprimento em 29%; já as reconstruções panorâmicas de TCFC subestimaram o comprimento em 4%. Abstract in english INTRODUCTION: This in vivo study assessed accuracy and reliability of tooth length measurements obtained from conventional panoramic radiographs and CBCT panoramic reconstructions to that of a digital caliper (gold standard). METHODS: The sample consisted of subjects who had CBCT and conventio [...] nal panoramic radiographic imaging and who required maxillary premolar extraction for routine orthodontic treatment. A total of 48 teeth extracted from 26 subjects were measured directly with digital calipers. Radiographic images were scanned and digitally measured in Dolphin 3D software. Accuracy of tooth length measurements made by CBCT panoramic reconstructions, conventional panoramic radiographs and digital caliper (gold standard) were compared to each other by repeated measures one-way ANOVA with Bonferroni correction and by single measures intraclass correlation coefficient. RESULTS: Repeated root length measures with digital calipers, panoramic radiographs and CBCT constructed panoramic-like images were all individually highly reliable. Compared to the caliper (gold standard), tooth measurements obtained from conventional panoramic radiographs were on average 6.3 mm (SD = 2.0 mm) longer, while tooth measurements from CBCT panoramic reconstructions were an average of 1.7 mm (SD = 1.2 mm) shorter. CONCLUSIONS: In comparison to actual tooth lengths, conventional panoramic radiographs were relatively inaccurate, overestimating the lengths by 29%, while CBCT panoramic reconstructions underestimated the lengths by 4%.

  14. 21 CFR 872.3910 - Backing and facing for an artificial tooth.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Backing and facing for an artificial tooth. 872.3910 Section 872.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... artificial tooth. (a) Identification. A backing and facing for an artificial tooth is a device intended...

  15. Non-destructive management of white spot lesions by using tooth jewelry

    OpenAIRE

    Kim, Hee-Jin; Karanxha, Lorena; PARK, Su-Jung

    2012-01-01

    Although several methods including composite resin restoration and microabrasion have been used for management of white spot lesion, tooth jewelry can be considered as another noninvasive option. This case report describes the management of white spot lesions by using tooth jewelry. This report also highlights the patients' preference for tooth jewelry as an esthetic concern.

  16. 21 CFR 872.3900 - Posterior artificial tooth with a metal insert.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Posterior artificial tooth with a metal insert... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3900 Posterior artificial tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is...

  17. Patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment

    DEFF Research Database (Denmark)

    Hartlev, Jens; Kohberg, Peter

    2014-01-01

    OBJECTIVES: To assess patient satisfaction and esthetic outcome after immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment and a provisional crown followed by later placement of a definitive crown. MATERIALS AND METHODS: In private practice, a single-tooth implant was placed immediately after tooth extraction in the esthetic zone of 54 patients. A definitive individual abutment and a provisional crown were mounted in the same visit. The definitive crown was placed after a mean period of 7 months. After a mean follow-up period of 33 months, the subjective and professional evaluation of the total implant treatment, peri-implant soft tissues, and implant crown were assessed on a 10-cm visual analog scale (VAS). The professional esthetic treatment outcome was also evaluated using pink esthetic score (PES), white esthetic score (WES), and total score of PES/WES. RESULTS: The evaluation of total implant treatment, peri-implant soft tissues, and implant crown demonstrated a significantly higher subjective than professional score for all 3 parameters (P < 0.001), for example, for the overall treatment, the mean scores were 9.4 and 7.0, respectively. A significant positive correlation was revealed between the professional VAS scores and the PESs and WESs. CONCLUSIONS: Immediate placement and provisionalization of single-tooth implants involving a definitive individual abutment and provisional crown followed by later placement of a definitive crown demonstrated high subjective and professional satisfaction. Generally, the professionals seem to be more critical than the patients. A strong correlation was observed between the professional VAS scores and the PES and WES scoring systems.

  18. Altered distribution of HMGB1 in the periodontal ligament of periostin-deficient mice subjected to Waldo's orthodontic tooth movement.

    Science.gov (United States)

    Li, Juan; Feng, Wei; Liu, Bo; Sun, Bao; Han, Xiuchun; Du, Juan; Sun, Jing; Yimin; Cui, Jian; Guo, Jie; Kudo, Akira; Amizuka, Norio; Li, Minqi

    2015-06-01

    Periostin is essential for the integrity and function of the periodontal ligament (PDL), and periostin knockout is related to an enhanced inflammatory status in PDL. High mobility group box 1 (HMGB1), a late inflammatory cytokine, is up-regulated in PDL cells in response to mechanical stress. This study aimed to investigate the effect of periostin deficiency (Pn-/-) on HMGB1 expression in PDL during orthodontic tooth movement. We used 8-week-old male mice homozygous for the disrupted periostin gene and their wild-type (WT) littermates. Tooth movement was performed according to Waldo's method, in which 0.5-mm-thick elastic bands were inserted between the first and second upper molars of anesthetized mice. After 3 days of mechanical loading, mice were fixed by transcardial perfusion of 4% paraformaldehyde in phosphate buffer, and the maxilla was extracted for histochemical analyses. Compared with the WT group, Pn-/- mice showed higher basal expression of HMGB1 in the absence of mechanical loading. Following 3 days of orthodontic tooth movement, the PDL in the compression side of both groups was almost replaced by cell-free hyaline zones, and Pn-/- mice showed a much wider residual PDL than WT mice. In the tension side, the number of HMGB1-positive cells in PDL in both Pn-/- and WT groups increased remarkably without a significant difference between the two groups. Our findings suggest an inhibitory effect of periostin on HMGB1 production by PDL and confirmed the critical role of periostin in integrity of PDL collagen fibrils during orthodontic tooth movement, although mechanical loading is the predominant stimulant of HMGB1 expression relative to periostin deficiency. PMID:25948513

  19. Age-related peculiarities of tooth enamel as a natural EPR biodosimeter

    International Nuclear Information System (INIS)

    The influence of age on tooth enamel as an EPR dosimeter has been investigated using a big collection of teeth extracted from several tens of persons living in different regions of Ukraine. The study was focused on two groups of teeth. The first one represented the urban population while the second corresponded to residents of rural settlements. Age dependences of two above groups were quite different: for example, doses for the 65-75 year age group were approximately 200 mGy higher for urban population compared to habitants of rural settlements. This effect was explained by contribution of medical X-ray exposure: the comparison of corresponding lingual and buccal doses revealed the more frequent presence of X-ray dose for urban population. Another observed effect was the difference between average intensities of native signals for two studied groups. At present time, no correlation with age was seen for this effect

  20. Effect of bleaching gel in Ca, P and Zn content in tooth enamel evaluated by ?-EDXRF

    Science.gov (United States)

    Godinho, J.; Silveira, J.; Mata, A.; Carvalho, M. L.; Pessanha, S.

    2014-10-01

    The purpose of this in vitro study is to assess whether the elemental content of P, Ca and Zn in tooth enamel is altered when bleaching the teeth with bleaching gel. In order to perform this evaluation, sound vestibular surfaces of six anterior healthy teeth, extracted for periodontal or orthodontic reasons were used. Cuts were made in order to obtain 8 × 2 mm samples. Samples were then treated with the bleaching product (Opalescence PF 10%) accordingly to manufacturer instructions and stocked in artificial saliva between each application. The elemental content of each sample, before and after treatment was obtained by a portable micro Energy Dispersive X-ray Spectrometry (?-EDXRF), making use of a polycapillary optic to obtain a focal spot of 100 ?m for Fe-K?. Quantitative calculations were obtained by WinAXIL compare mode method, using four standard reference materials. The obtained results show that no significant statistic differences were observed for the studied elements.

  1. Association of physical properties and maintenance of sterility of primary teeth in human tooth bank

    Directory of Open Access Journals (Sweden)

    Nitika Bajaj

    2014-01-01

    Full Text Available Background: This study was carried out to evaluate the sterility and structural integrity of stored primary teeth in artificial saliva over a storage period of 12 weeks (3 months in human tooth bank (HTB. Materials and Methods: A total of 80 freshly extracted teeth were taken and were categorized into four groups of 20 each. The samples were stored at 4°C for 12 weeks (3 months in the refrigerator. During their storage time of 3 months, they were repetitively evaluated for their sterility, enamel hardness, calcium and phosphate solubility and color stability at regular intervals of 3 weeks. Observations and Results: That teeth stored in artificial saliva maintained their sterility throughout the storage time of 12 weeks, but changes in their physical and chemical properties occurred with an increase in storage time. Conclusion: Storage time not more than 9 weeks is recommended for deciduous teeth to be stored in artificial saliva in a HTB.

  2. ESR Dosimetry Below 1 Gy, in X-Ray Irradiated Tooth Enamel

    International Nuclear Information System (INIS)

    Tooth enamel, extracted from molars, was irradiated with 66keV X-rays, with doses up to 1Gy.The preparation of the powder samples is described, as well as the protocol for the acquisition and processing of the spectra.The radiation induced paramagnetism is measured, at room temperature, by ESR Spectroscopy.The ESR spectra is well described considering two paramagnetic species, with magnetic moments (in units of Bohr magnetons) g=2,0041, and g1=2,0018, g2=1,9972.The ESR data (peak-to-peak amplitude per mg, hpp/mg, vs dose D), for doses 0Gy2 =0,996) with the linear expression: [hpp/mg] = -0,2( 0,4)+14,9(0,5). D [Gy].The result supports the growing confidence in the use of this material, and method, in Retrospective Dosimetry

  3. Dose estimation of two victims in a severe radiation accident by using tooth enamel

    International Nuclear Information System (INIS)

    Objective: To estimate the exposed dose levels of 2 two victims, who died one month after they were accidentally irradiated by Cobalt-60. Methods: Three teeth were extracted from 2 victims. The signal intensities of separated enamel samples were measured with ESR spectrometer. The accumulated exposed doses were reconstructed according to a calibration curve established using Cobalt-60 ?-rays. Results: A calibration curve between signal intensity and exposed dose was established. The estimated doses of 3 teeth were 26.1 ? 29.4 Gy, for victim A, 14.9 ? 18.3 Gy and 15.2 ? 18.5 Gy for victim B. The doses are close to the result of the other Laboratory. Conclusion: The application of ESR dosimetry in human tooth enamel could provide important information for a dose estimation of victims exposed to heavy doses of radiation. (authors)

  4. Study on the tooth enamel as a personal life-time dosimeter

    International Nuclear Information System (INIS)

    This paper is a summary of the results of basic and applied research on dental electron spin resonance (ESR) dosimetry for more than 15y. The material used in these experiments is enamel of human permanent teeth, which were extracted during normal dental treatment. The enamel was scrupulously separated from other parts of teeth with skillful techniques, pulverized in an agate mortar, and then sifted through several sieves to collect the uniform particle size. ESR measurements of the enamel samples were carried out at room temperature using an X-band spectrometer (JEOLRE1X). Although the limitations of ESR signal detection still remain, the study shows the useful application of dental ESR dosimetry not only in cases of radiation accidents and radiation therapy but also in cases of routine radiation work. The tooth enamel can be considered as a life-time dosimeter. (author)

  5. Comparative Study of Streptococcus mutans Laboratory Strains and Fresh Isolates from Carious and Caries-Free Tooth Surfaces and from Subjects with Hereditary Fructose Intolerance

    OpenAIRE

    Vadeboncoeur, Christian; Trahan, Luc

    1983-01-01

    This study was undertaken to investigate and compare some biochemical and physiological properties related to sugar metabolism of 4 laboratory strains and 13 freshly isolated strains of Streptococcus mutans from carious and caries-free tooth surfaces and from subjects with hereditary fructose intolerance. Growth in Trypticase (BBL Microbiology Systems)-yeast extract in the presence of various sugars was almost the same for all of the fresh isolates, which grew generally better than the labora...

  6. Epithelial histo-morphogenesis during mouse tooth development.

    Czech Academy of Sciences Publication Activity Database

    Lesot, H.; Fausser, J. L.; Kieffer-Combeau, S.; Coin, R.; Meyer, J. M.; Peterková, Renata; Peterka, Miroslav; Ruch, J. V.

    La LondelesMaures : organising comittee, 2001. s. 0-16. [Seventh International Conference on Tooth Morphogenesis and Differentiation. 16.06.2001-21.06.2001, La Londe-les-Maures] R&D Projects: GA MŠk OC B8.10 Keywords : molar * teeth Subject RIV: EA - Cell Biology

  7. Contribution of the tooth bud mesenchyme to alveolar bone.

    Czech Academy of Sciences Publication Activity Database

    Diep, L.; Matalová, Eva; Mitsiadis, T. A.; Tucker, A. S.

    312B, ?. 5 (2009), 510-517. ISSN 1552-5007 R&D Projects: GA ?R GC524/08/J032; GA AV ?R KJB500450802 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth * alveolar bone * bud Subject RIV: FF - HEENT, Dentistry Impact factor: 2.938, year: 2009

  8. Pinion tooth surface generation strategy of spiral bevel gears

    Science.gov (United States)

    Liu, Guanglei; Fan, Hongwei

    2012-07-01

    Aviation spiral bevel gears are often generated by spiral generated modified (SGM) roll method. In this style, pinion tooth surface modified generation strategy has an important influence on the meshing and contact performances. For the optimal contact pattern and transmission error function, local synthesis is applied to obtain the machine-tool settings of pinion. For digitized machine, four tooth surface generation styles of pinion are proposed. For every style, tooth contact analysis (TCA) is applied to obtain contact pattern and transmission error function. For the difference between TCA transmission error function and design objective curve, the degree of symmetry and agreement are defined and the corresponding sub-objective functions are established. Linear weighted combination method is applied to get an equivalent objective function to evaluate the shape of transmission error function. The computer programs for the process above are developed to analyze the meshing performances of the four pinion tooth surface generation styles for a pair of aviation spiral bevel gears with 38/43 teeth numbers. The four analytical results are compared with each other and show that the incomplete modified roll is optimal for this gear pair. This study is an expansion to generation strategy of spiral bevel gears, and offers new alternatives to computer numerical control (CNC) manufacture of spiral bevel gears.

  9. Hair keratin mutations in tooth enamel increase dental decay risk.

    Science.gov (United States)

    Duverger, Olivier; Ohara, Takahiro; Shaffer, John R; Donahue, Danielle; Zerfas, Patricia; Dullnig, Andrew; Crecelius, Christopher; Beniash, Elia; Marazita, Mary L; Morasso, Maria I

    2014-12-01

    Tooth enamel is the hardest substance in the human body and has a unique combination of hardness and fracture toughness that protects teeth from dental caries, the most common chronic disease worldwide. In addition to a high mineral content, tooth enamel comprises organic material that is important for mechanical performance and influences the initiation and progression of caries; however, the protein composition of tooth enamel has not been fully characterized. Here, we determined that epithelial hair keratins, which are crucial for maintaining the integrity of the sheaths that support the hair shaft, are expressed in the enamel organ and are essential organic components of mature enamel. Using genetic and intraoral examination data from 386 children and 706 adults, we found that individuals harboring known hair disorder-associated polymorphisms in the gene encoding keratin 75 (KRT75), KRT75(A161T) and KRT75(E337K), are prone to increased dental caries. Analysis of teeth from individuals carrying the KRT75(A161T) variant revealed an altered enamel structure and a marked reduction of enamel hardness, suggesting that a functional keratin network is required for the mechanical stability of tooth enamel. Taken together, our results identify a genetic locus that influences enamel structure and establish a connection between hair disorders and susceptibility to dental caries. PMID:25347471

  10. Formation of tooth-bone interface in reptiles.

    Czech Academy of Sciences Publication Activity Database

    Dosed?lová, Hana; Glocová, K.; Moravcová Balková, Simona; Knotek, Z.; Tichý, F.; Buchtová, Marcela

    Martin : Slovenská anatomická spole?nost, 2013. s. 21-21. [International Congress of the Slovak Anatomical Society /43./ and Lojda Symposium on Histochemistry /50./. 04.06.2013-06.06.2013, Martin] Institutional support: RVO:67985904 Keywords : tooth- bone Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine

  11. Observation of tooth enamel and dentim in SEM.

    Czech Academy of Sciences Publication Activity Database

    Wandrol, Petr; Roubalíková, L.; Autrata, Rudolf

    Praha : ?eskoslovenská mikroskopická spole?nost, 2005, s. 45. [Mikroskopie 2005. Nové M?sto na Morav? (CZ), 24.2.2005-25.2.2005] R&D Projects: GA ?R(CZ) GA102/05/0886 Keywords : tooth enamel * dentin * AdHeSe * TotalEtch Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  12. Functional convergence in bat and toothed whale biosonars

    DEFF Research Database (Denmark)

    Madsen, P T; Surlykke, A

    2013-01-01

    Echolocating bats and toothed whales hunt and navigate by emission of sound pulses and analysis of returning echoes to form a self-generated auditory scene. Here, we demonstrate a striking functional convergence in the way these two groups of mammals independently evolved the capability to sense with sound in air and water.

  13. Tooth agenesis: from molecular genetics to molecular dentistry.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Fleischmannová, Jana; Sharpe, P. T.; Tucker, A. S.

    2008-01-01

    Ro?. 87, ?. 7 (2008), s. 617-623. ISSN 0022-0345 R&D Projects: GA AV ?R KJB500450802; GA MŠk OC B23.001; GA ?R GC524/08/J032 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth agenesis Subject RIV: FF - HEENT, Dentistry Impact factor: 3.142, year: 2008

  14. Selective ?2-adrenergic Antagonist Butoxamine Reduces Orthodontic Tooth Movement

    Science.gov (United States)

    Sato, T.; Miyazawa, K.; Suzuki, Y.; Mizutani, Y.; Uchibori, S.; Asaoka, R.; Arai, M.; Togari, A.; Goto, S.

    2014-01-01

    Recently, involvement of the sympathetic nervous system in bone metabolism has attracted attention. ?2-Adrenergic receptor (?2-AR) is presented on osteoblastic and osteoclastic cells. We previously demonstrated that ?-AR blockers at low dose improve osteoporosis with hyperactivity of the sympathetic nervous system via ?2-AR blocking, while they may have a somewhat inhibitory effect on osteoblastic activity at high doses. In this study, the effects of butoxamine (BUT), a specific ?2-AR antagonist, on tooth movement were examined in spontaneously hypertensive rats (SHR) showing osteoporosis with hyperactivity of the sympathetic nervous system. We administered BUT (1 mg/kg) orally, and closed-coil springs were inserted into the upper-left first molar. After sacrifice, we calculated the amount of tooth movement and analyzed the trabecular microarchitecture and histomorphometry. The distance in the SHR control was greater than that in the Wistar-Kyoto rat group, but no significant difference was found in the SHR treated with BUT compared with the Wistar-Kyoto rat control. Analysis of bone volume per tissue volume, trabecular number, and osteoclast surface per bone surface in the alveolar bone showed clear bone loss by an increase of bone resorption in SHR. In addition, BUT treatment resulted in a recovery of alveolar bone loss. Furthermore, TH-immunoreactive nerves in the periodontal ligament were increased by tooth movement, and BUT administration decreased TH-immunoreactive nerves. These results suggest that BUT prevents alveolar bone loss and orthodontic tooth movement via ?2-AR blocking. PMID:24868013

  15. Caspase-7 tooth germ and hair follicle development and maintenance.

    Czech Academy of Sciences Publication Activity Database

    Veselá, Barbora; Matalová, Eva

    Rome : ECDO, 2012. 257-257. [Euroconference from Death to Eternity /20./ and Training course on Concepts and Methods in Programmed Cell Death /9./. 14.09.2012-17.09.2012, Rome] R&D Projects: GA ?R(CZ) GAP502/12/1285 Institutional support: RVO:67985904 Keywords : caspase-7 * hair follicle * tooth germ Subject RIV: EA - Cell Biology

  16. Protection and Reinforcement of Tooth Structures by Dental Coating Materials

    Directory of Open Access Journals (Sweden)

    Toru Nikaido

    2012-10-01

    Full Text Available It has been proposed that a resin coating can serve as a means to protect dental structure after preparation of the tooth for indirect restorations, sealing the exposed dentin. The resin coating is applied on the cut surfaces immediately after tooth preparation and before making an impression by assembling a dentin bonding system and a flowable composite. Resin coatings minimize pulp irritation and improve the bond strength between a resin cement and tooth when bonding the restoration to tooth. Recently, thin-film coating dental materials based on all-in-one adhesive technology were introduced for resin coating of indirect restorations. The thin coating materials are applied in a single clinical step and create a barrier-like film layer on the prepared dentin. The thin coatings play an important role in protecting the dentin from physical, chemical, and biological irritation. In addition, these thin-film coating materials reportedly prevent marginal leakage beneath inlays or crown restorations. In light of the many benefits provided by such a protective layer, these all-in-one adhesive materials may therefore also have the potential to cover exposed root dentin surfaces and prevent caries formation. In this paper, recent progress of the dental coating materials and their clinical applications are reviewed.

  17. In vitro color change of three dental veneering resins in tea, coffee and tamarind extracts

    OpenAIRE

    Muttagi, S.; J.K. Subramanya

    2011-01-01

    Objective: To study the in vitro color changes of three dental resin veneering materials when immersed in tea, coffee and tamarind extracts.Materials and Methods: The color changes of heat polymerized tooth colored acrylic resin (Stellondetrey, B, F14, DPI Dental products of India Ltd, Mumbai), auto polymerized tooth colored acrylic resin (DPI, B, QV5, DPI Dental products of India Ltd, Mumbai) andlight polymerized resin composite (Herculite XRV, Enamel A2, part no. 22860, lot no. 910437, Kerr...

  18. Tooth engineering: searching for dental mesenchymal cells sources.

    Directory of Open Access Journals (Sweden)

    HervéLesot

    2011-03-01

    Full Text Available The implantation of cultured re-associations between embryonic dental mesenchymal cells and epithelial cells from mouse molars at ED14 allowed making full teeth with crown, root, periodontal ligament fibers and bone. Although representing valuable tools to set up methodologies embryonic cells are not easily available. This work thus aimed to replace the embryonic cells by dental mesenchymal cell lines or cultured expanded embryonic cells, and to test their ability to mediate tooth development in vitro when re-associated with a competent dental epithelium. Histology, immunostaining and RT-PCR allowed getting complementary sets of results. Two different immortalized cell lines from ED18 dental mesenchyme failed in mediating tooth formation. The potentialities of embryonic dental mesenchymal cells decreased from ED14 to ED16 and were lost at ED18. This is likely related to a change in the mesenchymal cell phenotype and/or populations during development. Attempts to cultivate ED14 or ED16 embryonic dental mesenchymal cells prior to re-association led to the loss of their ability to support tooth development. This was accompanied by a down-regulation of Fgf3 transcription. Supplementation of the culture medium with FGF2 allowed restoring Fgf3 expression, but not the ability of mesenchymal cells to engage in tooth formation. Altogether, these observations suggest that a competent cell population exists in the dental mesenchyme at ED14, progressively decreases during development, and cannot as such be maintained in vitro. This study evidenced the need for specific conditions to maintain the ability of dental mesenchymal cells to initiate whole tooth formation, when re-associated with an odontogenic epithelium. Efforts to improve the culture conditions will have to be combined with attempts to characterize the competent cells within the dental mesenchyme.

  19. On optimization of internal/external spur gears tooth bending strength

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2014-01-01

    Gear fatigue strength is primarily controlled by the durability and load capacity, the first is typically related to pitting damage and the second to tooth-breakage. The pitting is due to the tooth contact and the shape of the contacting surfaces, the tooth breakage is controlled by the stress level at the tooth root. As with most machine elements the design/geometry is defined in standards (ISO). The present work focuses on changing the tooth root design of both external and internal gears, in ...

  20. Efficiency in bracket bonding with the use of pretreatment methods to tooth enamel before acid etching: sodium hypochlorite vs. hydrogen peroxide techniques.

    Science.gov (United States)

    Rivera-Prado, Hermann; Moyaho-Bernal, Ángeles; Andrade-Torres, Alejandro; Franco-Romero, Guillermo; Montiel-Jarquín, Álvaro; Mendoza-Pinto, Claudia; García-Cano, Eugenio; Hernández-Ruíz, Ana K

    2015-04-01

    Bond failures are produced by the existence of biofilm on the tooth surface. Because biofilm is impermeable, it prevents contact in many areas, reducing the etching effect which selectively dissolves calcified tissues but does not seem to eliminate biofilm from the tooth surface, and thus the bond between the tooth and the bracket is not strong enough. The aim of this study is to compare bracket bonding efficiency with two dental surface pretreatments: sodium hypochlorite vs. hydrogen peroxide techniques. This was a cross-sectional, comparative, in vitro study. Seventy-five premolars extracted for orthodontic purposes were evaluated. They were divided into three groups of 25 teeth and assigned randomly toone of the pretreatment techniques (5.25%sodium hypochlorite or 3.5% hydrogen peroxide) or to a control group. The most efficient pretreatment technique for bonding to brackets was sodium hypochlorite, with an average of 17.15 (kg/F). Significant differences were observed between groups (p=0.0001). The post hoc bond strength test showed statistically significant differences between the sodium hypochlorite technique and the control group (p=0.0001). The sodium hypochlorite technique improves bracket adhesion to tooth enamel. PMID:25950167

  1. Multiple tooth resorption in an Italian Greyhound

    International Nuclear Information System (INIS)

    An Italian greyhound was presented three times during a two-year period for dental prophylaxis due to periodontal disease. Clinical examination revealed lesions on several teeth. Radiographs revealed extensive resorptive root lesions. On histological examination, the presence of odontoclasts and signs of boney remodeling of the roots confirmed the resorptive nature of the lesions. Given the extent of the lesions, and poor prognosis with conservative treatment alone, teeth affected by the most severe resorption were extracted at each visit using a flap technique combined with alveolar vestibular osteotomy. Dental resorptive lesions are rarely detected in the dog but may be more frequent than previously thought. The routine use of dental radiographs can be used to reveal these lesions in the dog

  2. Computation of tooth axes of existent and missing teeth from 3D CT images.

    Science.gov (United States)

    Wang, Yang; Wu, Lin; Guo, Huayan; Qiu, Tiantian; Huang, Yuanliang; Lin, Bin; Wang, Lisheng

    2015-12-01

    Orientations of tooth axes are important quantitative information used in dental diagnosis and surgery planning. However, their computation is a complex problem, and the existing methods have respective limitations. This paper proposes new methods to compute 3D tooth axes from 3D CT images for existent teeth with single root or multiple roots and to estimate 3D tooth axes from 3D CT images for missing teeth. The tooth axis of a single-root tooth will be determined by segmenting the pulp cavity of the tooth and computing the principal direction of the pulp cavity, and the estimation of tooth axes of the missing teeth is modeled as an interpolation problem of some quaternions along a 3D curve. The proposed methods can either avoid the difficult teeth segmentation problem or improve the limitations of existing methods. Their effectiveness and practicality are demonstrated by experimental results of different 3D CT images from the clinic. PMID:25941910

  3. Characteristics of Rotary Electromagnet with Large Tooth-pitch Angle

    Directory of Open Access Journals (Sweden)

    Ruan Jian

    2012-10-01

    Full Text Available Since the conventional electro-mechanical converter of 2D valve had problems of step lose due to its small tooth-pitch angle, a novel rotary electromagnet with large tooth-pitch angle and coreless rotor structure was proposed. Combined with the approaches of magnetic circuit analysis, finite element simulation and experimental study, the static and dynamic characteristics of electromagnet including torque-angle characteristics, frequency response and step response were studied. The experimental results are in a close agreement with the simulated results. The electromagnet has sinusoidal torque-angle characteristics and good dynamic response. The maximum static torque is approximately 0.083N.M, and its frequency width is about 125Hz/-3dB, 130Hz/-90°, respectively, and the rise time is about 5.5 ms. It is appropriate to be used as the electro-mechanical converter of 2D proportional valve.

  4. Smile enhancement the conservative way: Tooth whitening procedures

    Directory of Open Access Journals (Sweden)

    Thosre Deepika

    2009-01-01

    Full Text Available This article presents clinical cases in which different bleaching modalities have been used to successfully treat unsightly teeth. Depending upon the type and severity of discoloration, in-office vital and nonvital bleaching procedures were carried out. Discoloration of a single tooth has been managed using nonvital bleaching alone or with a combination of other minimally invasive modalities for an acceptable esthetic outcome. The case selection was done by considering the patient?s needs and expectations, the type and cause of discoloration and patient economics. Moreover, prime importance was given to the conservation of the existing tooth structure and acquiring a complete change in the shade of teeth, which was comparable to that of the adjacent teeth. The desire to have a bright smile has become an important esthetic need of patients. The article explores various forms of bleaching and their successful usage in day-to-day clinical practice.

  5. Associação na mesma família das doenças de Charcot-Marie-Tooth e de Friedreich / Association of Charcot-Marie-Tooth and Friedreich diseases in a family

    Scientific Electronic Library Online (English)

    Charles Peter, Tilbery; Décio Cassiani, Altimari; Luiz G., Gagliardi-Ferreira; José L., Alonso Nieto.

    1972-06-01

    Full Text Available Quatro irmãos com moléstias de Charcot-Marie-Tooth são estudados do ponto de vista clínico e genético. São ressaltadas, mediante análise da sintomatologia, as formas de transição no grande grupo de moléstias heredodegenerativas, sendo atribuída particular ênfase às formas entre a moléstia de Charcot [...] -Marie-Tooth e a de Friedreich. Nos casos apresentados havia sinais clínicos da amiotrofia de Charcot-Marie-Tooth e da degeneração espinocerebelar de Friedreich. No estudo genético foram observadas aberrações cromossômicas, fenômeno inédito na moléstia de Charcot-Marie-Tooth. Abstract in english Four brothers with Charcot-Marie-Tooth disease are studied clinically and genetically. By comparing the symptomatology, the mixed clinical forms within the great group of heredodegenerative diseases are enfazised, with special attention to the intermediate forms between Charcot-MarieTooth and Friedr [...] eich diseases. In the present cases there were signs of Charcot-Marie-Tooth's peroneal muscular atrophy and Friedreich's spinocerebelar degeneration. By the genetic study a cromosomal breakage, an unusual phenomenon in Charcot-Marie-Tooth disease, was observed.

  6. Molar tooth development in caspase-3 deficient mice.

    Czech Academy of Sciences Publication Activity Database

    Matalová, Eva; Sharpe, P. T.; Lakhani, S. A.; Roth, K. A.; Flavell, R. A.; Šetková, Jana; Míšek, Ivan; Tucker, A. S.

    2006-01-01

    Ro?. 50, 5 (2006), s. 491-497. ISSN 0214-6282 R&D Projects: GA AV ?R KJB500450503; GA MŠk OC B23.001 Grant ostatní: European Molecular Biology Organization ASTF195.00-05; NIH NS41962 Institutional research plan: CEZ:AV0Z50450515 Keywords : tooth development * dental apoptosis * caspase-3 mutant Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.577, year: 2006

  7. Tooth bleaching--a critical review of the biological aspects

    DEFF Research Database (Denmark)

    Dahl, J E; Pallesen, Ulla

    2003-01-01

    Present tooth-bleaching techniques are based upon hydrogen peroxide as the active agent. It is applied directly, or produced in a chemical reaction from sodium perborate or carbamide peroxide. More than 90% immediate success has been reported for intracoronal bleaching of non-vital teeth, and in the period of 1-8 years' observation time, from 10 to 40% of the initially successfully treated teeth needed re-treatment. Cervical root resorption is a possible consequence of internal bleaching and is ...

  8. Effect of Bisphosphonates on Orthodontic Tooth Movement—An Update

    OpenAIRE

    Krishnan, Sindhuja; Pandian, Saravana; Kumar S, Aravind

    2015-01-01

    Bisphosphonates are a synthetic class of pyrophosphate analogues that are powerful inhibitors of bone resorption which are commonly used as a medication for the prevention and therapy of osteoporosis and osteopenia, also used to treat tumor diseases. As it affects bone metabolism, it is said to have an influence on orthodontic treatment and tooth movement. Also, this review gives an insight into the reported effects of Bisphosphonate medication in literature highlighting the status quo of sci...

  9. Study of Tooth Cement Using Variable Pressure SEM.

    Czech Academy of Sciences Publication Activity Database

    Ned?la, Vilém; Roubalíková, L.

    Prague : Czechoslovak Microscopy Society, 2007 - (Nebesá?ová, J.; Hozák, P.), s. 293-294 ISBN 978-80-239-9397-4. [Multinational Congress on Microscopy /8./. Prague (CZ), 17.06.2007-21.06.2007] R&D Projects: GA ?R(CZ) GA102/05/0886; GA AV ?R KJB200650602 Institutional research plan: CEZ:AV0Z20650511 Keywords : tooth cement * enamel * VP-SEM Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  10. Trace elements can influence the physical properties of tooth enamel

    OpenAIRE

    Ghadimi, Elnaz; Eimar, Hazem; Marelli, Benedetto; Nazhat, Showan N; Asgharian, Masoud; Vali, Hojatollah; Tamimi, Faleh

    2013-01-01

    In previous studies, we showed that the size of apatite nanocrystals in tooth enamel can influence its physical properties. This important discovery raised a new question; which factors are regulating the size of these nanocrystals? Trace elements can affect crystallographic properties of synthetic apatite, therefore this study was designed to investigate how trace elements influence enamel’s crystallographic properties and ultimately its physical properties.

  11. ON THE R-CURVE BEHAVIOR OF HUMAN TOOTH ENAMEL

    OpenAIRE

    Bajaj, Devendra; Arola, Dwayne

    2009-01-01

    In this study the crack growth resistance behavior and fracture toughness of human tooth enamel were quantified using incremental crack growth measures and conventional fracture mechanics. Results showed that enamel undergoes an increase in crack growth resistance (i.e. rising R-curve) with crack extension from the outer to the inner enamel, and that the rise in toughness is function of distance from the Dentin Enamel Junction (DEJ). The outer enamel exhibited the lowest apparent toughness (0...

  12. Towards Unraveling the Human Tooth Transcriptome: The Dentome

    OpenAIRE

    Hu, Shijia; Parker, Joel,; Wright, John Timothy

    2015-01-01

    The goal of the study was to characterize the transcriptome profiles of human ameloblasts and odontoblasts, evaluate molecular pathways and advance our knowledge of the human “dentome”. Laser capture microdissection was used to isolate odontoblasts and ameloblasts from human tooth buds (15-20week gestational age) from 4 fetuses. RNA was examined using Agilent 41k whole genome arrays at 2 different stages of enamel formation, presecretory and secretory. Probe detection was considered against t...

  13. Comparative evaluation of soft tissue characteristics around implant and tooth

    Directory of Open Access Journals (Sweden)

    Paknejad M.

    2008-12-01

    Full Text Available "nBackground and Aim: Soft tissue condition around dental implant is an essential part for long term healthy and esthetic outcome. The aim of this study was to compare soft tissue dimensions between implant supported single  tooth replacement and the contra-lateral natural tooth. "nMaterials and Methods: This retrospective study was performed on dentate patients treated with anterior single  tooth implant at least 1 year ago. Of twenty eight, fourteen patients had been treated with one stasge method and others with two stage method. Biologic width (BW, papilla index (PI, and mucosal thickness (MT were evaluated around implants and contra-lateral teeth clinically and compared with each other. The Wilcoxon test, Mann-Whitney test, and Student pair t-test were used to assess the differences between one stasge and two stage implants, and implant and tooth groups. "nResults: The mean BW around one stasge implants, two stage implants, and contra-lateral teeth were 1.42±0.48 mm, 1.67±0.48 mm, and 1.47±0.60 mm, respectively. The mean PI adjacent to one stasge implants, Two stage implants, and contra-lateral teeth were 2.50±0.52, 2.53±0.55, and 2.72±0.47, correspondingly. The mean MT around one stasge implants, two stage implants, and contra-lateral teeth were 3.10±0.48, 3.09±0.75, and 2.57±0.88, respectively. There was no statistically significant difference among one stasge implants, two stage implants, and contra-lateral teeth with regard to measured variables. "nConclusion: Based on the results of this investigation, in standard condition, it seems that there is no noticeable difference in indicators of; biologic width, papilla index, and mucosal thickness around one stasge implants, two stage implants, and contra-lateral teeth.

  14. Biological aspects of tooth fragment reattachment in immature incisors

    OpenAIRE

    Kalra N; Rai P

    2005-01-01

    Tooth fragment reattachment is a relatively new technique and there are many aspects which still need to be explored. Reported here is a case of enamel and dentin fracture of 11 and 21. There was a very thin layer of dentin clinically over the pulp chamber and the root apices were immature. The reattachment procedure was modified slightly. The initial joint was made with protective calcium hydroxide and glass ionomer cement on the approximating surfaces. The further reattachment was accomplis...

  15. An interdisciplinary approach to treat crown-root-fractured tooth

    OpenAIRE

    Sun, Ying Chun; Li, Ying; Tong, Jian; Ping GAO

    2013-01-01

    Restoration of a crown-root subgingival fractured tooth, especially at anterior aesthetic zones is still a great challenge for restorative dentists. Crown lengthening procedure alone has the disadvantage of high gingival curve of the final restoration, which was not discontinuous to adjacent teeth and thus compromise cosmetic outcomes. The objective of this report is to display a new interdisciplinary approach which combining endodontic root canal treatment, orthodontic extrusion, periodontal...

  16. Classification of severe tooth discolorations and treatment options

    OpenAIRE

    Tran, Huy Quoc; Jenssen, Lotte

    2011-01-01

    In this literature study, a classification of severe discolorations and a summary over the options for different dental treatments have been described. Various causes of these severe discolorations are presented and how the mechanisms behind tooth discolorations affect the outcome of a treatment or treatment options. Finally, the aesthetic outcome of a possible bleaching treatment of the different classified discolorations is discussed. In the management of patients with stained teeth it i...

  17. Joubert syndrome: congenital cerebellar ataxia with the “molar tooth

    OpenAIRE

    Romani, Marta; Micalizzi, Alessia; Valente, Enza Maria

    2013-01-01

    Joubert syndrome (JS) is a congenital cerebellar ataxia with autosomal recessive or X-linked inheritance, which diagnostic hallmark is a unique cerebellar and brainstem malformation recognizable on brain imaging, the “molar tooth sign”. Neurological signs are present from neonatal age and include hypotonia evolving into ataxia, global developmental delay, ocular motor apraxia and breathing dysregulation. These are variably associated with multiorgan involvement, mainly of the retina, kidneys,...

  18. Towards unraveling the human tooth transcriptome: the dentome.

    Science.gov (United States)

    Hu, Shijia; Parker, Joel; Wright, John Timothy

    2015-01-01

    The goal of the study was to characterize the transcriptome profiles of human ameloblasts and odontoblasts, evaluate molecular pathways and advance our knowledge of the human "dentome". Laser capture microdissection was used to isolate odontoblasts and ameloblasts from human tooth buds (15-20week gestational age) from 4 fetuses. RNA was examined using Agilent 41k whole genome arrays at 2 different stages of enamel formation, presecretory and secretory. Probe detection was considered against the array negative control to control for background noise. Differential expression was examined using Significance Analysis of Microarrays (SAM) 4.0 between different cell types and developmental stages with a false discovery rate of 20%. Pathway analysis was conducted using Ingenuity Pathway Analysis software. We found that during primary tooth formation, odontoblasts expressed 14,802 genes, presecretory ameloblasts 15,179 genes and secretory ameloblasts 14,526 genes. Genes known to be active during tooth development for each cell type (eg COL1A1, AMELX) were shown to be expressed by our approach. Exploring further into the list of differentially expressed genes between the motile odontoblasts and non-motile presecretory ameloblasts we found several genes of interest that could be involved in cell movement (FN1, LUM, ASTN1). Furthermore, our analysis indicated that the Phospholipase C and ERK5 pathways, that are important for cell movement, were activated in the motile odontoblasts. In addition our pathway analysis identified WNT3A and TGFB1 as important upstream contributors. Recent studies implicate these genes in the development of Schimke immuno-osseous dysplasia. The utility of laser capture microdissection can be a valuable tool in the examination of specific tissues or cell populations present in human tooth buds. Advancing our knowledge of the human dentome and related molecular pathways provides new insights into the complex mechanisms regulating odontogenesis and biomineralization. This knowledge could prove useful in future studies of odontogenic related pathologies. PMID:25849153

  19. Mechanochemical control of mesenchymal condensation and embryonic tooth organ formation

    OpenAIRE

    Mammoto, Tadanori; Mammoto, Akiko; Torisawa, Yu-suke; Tat, Tracy; Gibbs, Ashley; Derda, Ratmir; Mannix, Robert; de Bruijn, Marlieke; Yung, Chong Wing; Huh, Dongeun; Ingber, Donald E.

    2011-01-01

    Mesenchymal condensation is critical for organogenesis, yet little is known about how this process is controlled. Here we show that Fgf8 and Sema3f produced by early dental epithelium respectively attract and repulse mesenchymal cells, which causes them to pack tightly together during mouse tooth development. Resulting mechanical compaction-induced changes in cell shape induce odontogenic transcription factors (Pax9, Msx1) and chemical cue (BMP4), and mechanical compression of mesenchyme is s...

  20. From Hopeless to Good Prognosis: Journey of a Failing Tooth

    OpenAIRE

    Gupta, Saurabh; Deshmukh, Jeevanand; Khatri, Richa; Kulkarni, Vinaya Kumar; Karthik, B

    2015-01-01

    Chronic periodontitis, along with associated clinical findings such as pathologic tooth migration, diastema, functional and aesthetic aberrations, poses an immense challenge to a dental professional. These findings convert clinical decision making into a daunting task and adversely affect the prognosis and the treatment plan for the presenting clinical problem. An interdisciplinary approach aimed at restoring functional and aesthetic needs of the affected individual within the limitations of ...

  1. Melatonin Effects on Hard Tissues: Bone and Tooth

    OpenAIRE

    Hong-Wen He; Fang Huang,; Jie Liu

    2013-01-01

    Melatonin is an endogenous hormone rhythmically produced in the pineal gland under the control of the suprachiasmatic nucleus (SCN) and the light/dark cycle. This indole plays an important role in many physiological processes including circadian entrainment, blood pressure regulation, seasonal reproduction, ovarian physiology, immune function, etc. Recently, the investigation and applications of melatonin in the hard tissues bone and tooth have received great attention. Melatonin has been inv...

  2. The relationship between dental fluorosis and tooth fluoride concentration - a study in an endemic area - doi:10.5020/18061230.2011.p355

    Directory of Open Access Journals (Sweden)

    Marc Daniel Grynpas

    2012-01-01

    Full Text Available Objective: To determine the relationship between dental fluorosis (DF severity and fluoride [F] concentration in tooth and water in DF endemic areas. Methods: Life-long residents from two DF endemic communities were studied. Forty-five extracted teeth were collected and analyzed for DF severity and tooth [F]. Thylstrup-Ferjeskov Index (TFI was used to measure DF severity and instrumental neutron activation analysis (INAA for tooth [F] concentration. Water from regional wells was also collected (n=9 and analyzed for F content using specific ion F electrode. Results: Water [F] varied between 0.2ppm and 4.7ppm. TFI scores ranged from 0 to 6; [F] from 120ppm to 2,140ppm in enamel and 304ppm to 4,800ppm in dentin. No correlation was found between DF severity and [F] in enamel (rs=0.22,p=0.15 and dentin (rs=-0.19,p=0.20, nor between water [F] and [F] in enamel (rs=-0.09,p=0.65 and dentin (rs=-0.11,p=0.56. Weak correlation between DF severity and water [F] (rs=0.38,p=0.04 was found. Linear regression analysis showed that TFI couldn’t be predicted from a linear combination of the independent variables (age, enamel and dentin [F]. When enamel, dentin and water [F] were used as independent variables in the linear regression (predict DF severity, only water [F] showed influence in DF severity (p=0.013;t=2.67. Conclusion: Even in areas of endemic DF, tooth [F] didn’t correlate with DF severity and the relationship between water [F] and DF severity was very weak. Therefore, tooth [F] may not be a good predictor/indicator of DF severity.

  3. Differential changes in gingival somatosensory sensitivity after painful electrical tooth stimulation

    DEFF Research Database (Denmark)

    Baad-Hansen, Lene; Lu, Shengyi

    2015-01-01

    We aimed to evaluate the effect of painful tooth stimulation on gingival somatosensory sensitivity of healthy volunteers in a randomized, controlled design. Thirteen healthy volunteers (six women, seven men; 28.4 ± 5.0 years) were included for two experimental sessions of electrical tooth stimulation: painful tooth stimulation and tooth stimulation below the sensory threshold (control). Eight of the human subjects participated in a third session without tooth stimulation. In all sessions, the somatosensory sensitivity of the gingiva adjacent to the stimulated tooth was evaluated with a standardized battery of quantitative sensory tests (QST) before, immediately after and 30 min after tooth stimulation. Painful tooth stimulation evoked significant decreases in warmth and heat pain thresholds (P 0.086). No QST changes were detected in the session without tooth stimulation (P > 0.060). In conclusion, modest increased gingival sensitivity to warmth, painful heat and pressure stimuli as well as desensitization to non-painful mechanical stimulation were demonstrated after tooth stimulation. This suggests involvement of competing heterotopic facilitatory and inhibitory mechanisms. Furthermore, stimulation below the sensory threshold induced similar thermal sensitization suggesting the possibility of activation of axon-reflex-like mechanisms even at intensities below the perception threshold. These findings may have implications for interpretation of somatosensory results in patients with chronic intraoral pain.

  4. The first Neanderthal tooth found North of the Carpathian Mountains

    Science.gov (United States)

    Urbanowski, Miko?aj; Socha, Pawe?; D?browski, Pawe?; Nowaczewska, Wioletta; Sadakierska-Chudy, Anna; Dobosz, Tadeusz; Stefaniak, Krzysztof; Nadachowski, Adam

    2010-04-01

    An upper second permanent molar from a human was found alongside numerous tools of the Micoquian tradition and was excavated in Stajnia Cave, which is located over 100 km North of the Carpathian Mountains in southern Poland. The age of these finds has been established within a time-span of late Saalian to early Weichselian, most likely to OIS 5c or 5a, according to the palaeontological, geological, archaeological and absolute dating of the layer from which they were obtained. An examination of the morphology of the human molar indicates that this tooth exhibits many traits frequently occurring in Neanderthal upper molars. Although the occurrence of derived Neanderthal traits in the Stajnia molar cannot be firmly established because of degradation of its cusps, the presence of the above-mentioned features allows the assertion that this tooth belonged to a Neanderthal. The age of the Stajnia tooth and the archaeological context of this find also indicate that this molar is of Neanderthal origin.

  5. Primary cilia integrate hedgehog and Wnt signaling during tooth development.

    Science.gov (United States)

    Liu, B; Chen, S; Cheng, D; Jing, W; Helms, J A

    2014-05-01

    Many ciliopathies have clinical features that include tooth malformations but how these defects come about is not clear. Here we show that genetic deletion of the motor protein Kif3a in dental mesenchyme results in an arrest in odontogenesis. Incisors are completely missing, and molars are enlarged in Wnt1(Cre+)Kif3a(fl/fl) embryos. Although amelogenesis and dentinogenesis initiate in the molar tooth bud, both processes terminate prematurely. We demonstrate that loss of Kif3a in dental mesenchyme results in loss of Hedgehog signaling and gain of Wnt signaling in this same tissue. The defective dental mesenchyme then aberrantly signals to the dental epithelia, which prompts an up-regulation in the Hedgehog and Wnt responses in the epithelia and leads to multiple attempts at invagination and an expanded enamel organ. Thus, the primary cilium integrates Hedgehog and Wnt signaling between dental epithelia and mesenchyme, and this cilia-dependent integration is required for proper tooth development. PMID:24659776

  6. Tooth segmentation system with intelligent editing for cephalometric analysis

    Science.gov (United States)

    Chen, Shoupu

    2015-03-01

    Cephalometric analysis is the study of the dental and skeletal relationship in the head, and it is used as an assessment and planning tool for improved orthodontic treatment of a patient. Conventional cephalometric analysis identifies bony and soft-tissue landmarks in 2D cephalometric radiographs, in order to diagnose facial features and abnormalities prior to treatment, or to evaluate the progress of treatment. Recent studies in orthodontics indicate that there are persistent inaccuracies and inconsistencies in the results provided using conventional 2D cephalometric analysis. Obviously, plane geometry is inappropriate for analyzing anatomical volumes and their growth; only a 3D analysis is able to analyze the three-dimensional, anatomical maxillofacial complex, which requires computing inertia systems for individual or groups of digitally segmented teeth from an image volume of a patient's head. For the study of 3D cephalometric analysis, the current paper proposes a system for semi-automatically segmenting teeth from a cone beam computed tomography (CBCT) volume with two distinct features, including an intelligent user-input interface for automatic background seed generation, and a graphics processing unit (GPU) acceleration mechanism for three-dimensional GrowCut volume segmentation. Results show a satisfying average DICE score of 0.92, with the use of the proposed tooth segmentation system, by 15 novice users who segmented a randomly sampled tooth set. The average GrowCut processing time is around one second per tooth, excluding user interaction time.

  7. Effect of experimental tooth clenching on the release of ?-endorphin

    DEFF Research Database (Denmark)

    Dawson, Andreas; Ljunggren, Lennart

    2014-01-01

    AIMS: To investigate the association between experimental tooth clenching and the release of ?-endorphin in patients with myofascial temporomandibular disorders (M-TMD) and healthy subjects. METHODS: Fifteen M-TMD patients and 15 healthy subjects were included and assigned an experimental tooth-clenching task. Venous blood was collected and pain intensity was noted on a visual analog scale. The masseter pressure pain threshold (PPT) was assessed 2 hours before the clenching task and immediately after. A mixed-model analysis of variance was used for statistical analyses. RESULTS: Significant main effects for time and group were observed for pain intensity and PPT, with significantly lower mean values of pain intensity (P < .001) and PPT (P < .01) after the clenching task compared with baseline. M-TMD patients had significantly higher pain intensity (P < .001) and significantly lower PPT (P < .05) than healthy subjects. No significant time or group effects were observed for the level of ?-endorphin. Neither pain intensity nor PPT correlated significantly with ?-endorphin levels. CONCLUSION: This experimental tooth-clenching task was not associated with significant alterations in ?-endorphin levels over time, but with mechanical hyperalgesia and low to moderate levels of pain in healthy subjects and M-TMD patients, respectively. More research is required to understand the role of the ?-endorphinergic system in the etiology of M-TMD.

  8. Evidence to support tooth brushing in critically ill patients.

    Science.gov (United States)

    Ames, Nancy J

    2011-05-01

    Tooth brushing in critically ill patients has been advocated by many as a standard of care despite the limited evidence to support this practice. Attention has been focused on oral care as the evidence accumulates to support an association between the bacteria in the oral microbiome and those respiratory pathogens that cause pneumonia. It is plausible to assume that respiratory pathogens originating in the oral cavity are aspirated into the lungs, causing infection. A recent study of the effects of a powered toothbrush on the incidence of ventilator-associated pneumonia was stopped early because of a lack of effect in the treatment group. This review summarizes the evidence that supports the effectiveness of tooth brushing in critically ill adults and children receiving mechanical ventilation. Possible reasons for the lack of benefit of tooth brushing demonstrated in clinical trials are discussed. Recommendations for future trials in critically ill patients are suggested. With increased emphasis being placed on oral care, the evidence that supports this intervention must be evaluated carefully. PMID:21532045

  9. Molecular analysis of tooth enamel by Raman spectroscopy after treatment with bleaching agents at different concentrations

    International Nuclear Information System (INIS)

    The changes in the concentration of the v1 phosphate molecule of the surface of dentin enamel are treated and researched with bleaching agents of chemical activation to basis of hydrogen peroxide than 9,5% and 14% and carbamide peroxide than 38%, for a period of 28 days. Raman spectroscopy was used and 30 dental pieces extracted, of which, were to be free of blemishes and pigmentations, without possessing fractures of the enamel, decay nor any other type of defect. The Raman spectrum was obtained of each dental piece prior to the application of bleaching agents. The specimens were separated into three experimental groups according to the concentration of whitening. The concentration of the v1 phosphate molecule was measured in the tooth enamel to the second and fourth week of treatment. In addition, ANOVA was performed for respective measurements (p?0.05). A reduction of the v1 phosphate molecule were observed during and after the bleaching process in the experimental groups that have used of hydrogen peroxide to 14% and carbamide peroxide 38%. In the group of hydrogen peroxide to 9,5% has remained unproven a significant reduction. Within the limitations of this study is concluded that the bleaching agent causes a loss of v1 phosphate. This loss has been greater in the whitening of higher concentration. In spite, that the possible effect remineralizing of the saliva on a teeth whitening process has been unevaluated, it is recommended using during and after the treatment, toothpastes, mouthwashes, chewing gums, dental floss, among others, that contain ACP to help to cushion the potential loss of phosphate from tooth enamel. (author)

  10. Fracture toughness of zirconia ceramic crowns made by feather-edge tooth preparation design

    Directory of Open Access Journals (Sweden)

    Mirkovi? Nemanja

    2012-01-01

    Full Text Available Background/Aim. Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of reduction of their mechanical properties. This research was done to establish effects of feather-edge tooth preparation on fracture toughness of single zirconia ceramic crowns. Methods. The research was performed as an experimental study. Sixty (60 ceramic crowns were made on non-carious extracted human premolars. Thirty (30 crowns were made on the basis of feather-edge preparation (experimental group I. The group II included 30 crowns made on 1 mm rounded shoulder. Crowns fabrication was executed on a copy mill production system “Zirkonzahn” (Zirkonzahn GMBH, Gais, Germany. The spherical compression test was used to determine fracture toughness, using 6 mm diameter ceramic ball. Fracture load for damaging ceramic crown was recorded on a universal testing machine - Zwick, type 1464, with the speed of 0.05 mm/min. Results. The results of this research introduced significant differences between fracture toughness of ceramic samples in every examined group. However, fracture toughness of crowns from both group was above 2 000 N, what was double beyond a recommended value. The mean value of fracture toughness in the feather-edge group was 2 090 N, and in shoulder group it was 2 214 N. Conclusion. This research showed a high fracture toughness of zirconia crowns made on feather-edge preparation. The examined crowns showed a fracture resistance at a sufficient distance in relation to the minimum values of functional loads. Further research of functional loads of these crown is necessary, as well as research of marginal adaptation of cemented crowns and gingival inflammatory response.

  11. TOOTH BRUSH - TOOTH PASTE OCULAR INJURY: A SEQUELAE TO FAST LIFE

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2015-01-01

    Full Text Available Toothbrush - tooth paste, widely used in every house hold, may cause irreversible injury to the eye especially cornea that comes into contact with this substance. We present two cases of toothbrush - toothpaste injury who accidentally injured their own eye. T hese were combination of chemical ( T oothpaste and trivial mechanical ( T oothbrush trauma. Ocular contact with toothpaste causes severe unbearable burning sensation. One of the cases developed suppurative corneal ulcer with hypopyon and lost vision in the affected eye. Toothpastes with more ph can cause blindness when it comes into contact with the eye if not treated urgently. The other patient ( O ne of the consultants in our institute reported immediately in the morning in emergency with complaints of seve re burning sensation in the involved eye after accidental injury with toothbrush - toothpaste. His eyes were washed with normal saline for 30 to 40 minutes. Because he was treated immediately, he recovered within one week. Clinicians should take adequate pre cautions to prevent serious complication. In case of an accidental contact of eye with toothpaste, it is important to wash the eye efficiently. We decided to estimate the ph of commonly used various brands of toothpaste in over biochemistry lab and it was found that ph of various toothpaste varies from 7 to 10. The pH of the brand of the toothpaste which was used by one of the case was (pH 9.6, which shows that it is a combination of mechanical and alkali injury. pH near to neutral (7.1 and 7.4 was detect ed in one of the herbal toothpaste and one the oldest brand of toothpaste ( W hich was not herbal. These cases are being reported to make aware the ophthalmologists and public that although rare but these cases should not be taken lightly and should be trea ted urgently to prevent the loss of vision in the involved eye. One of the risk factors, may be the hurried activities in the morning in this era of fast life a s one of the patients was working in a metropolitan city and the other a pathologist in our inst itution

  12. Phosphoproteomes of Strongylocentrotus purpuratus shell and tooth matrix: identification of a major acidic sea urchin tooth phosphoprotein, phosphodontin

    Directory of Open Access Journals (Sweden)

    Mann Matthias

    2010-02-01

    Full Text Available Abstract Background Sea urchin is a major model organism for developmental biology and biomineralization research. However, identification of proteins involved in larval skeleton formation and mineralization processes in the embryo and adult, and the molecular characterization of such proteins, has just gained momentum with the sequencing of the Strongylocentrotus purpuratus genome and the introduction of high-throughput proteomics into the field. Results The present report contains the determination of test (shell and tooth organic matrix phosphoproteomes. Altogether 34 phosphoproteins were identified in the biomineral organic matrices. Most phosphoproteins were specific for one compartment, only two were identified in both matrices. The sea urchin phosphoproteomes contained several obvious orthologs of mammalian proteins, such as a Src family tyrosine kinase, protein kinase C-delta 1, Dickkopf-1 and other signal transduction components, or nucleobindin. In most cases phosphorylation sites were conserved between sea urchin and mammalian proteins. However, the majority of phosphoproteins had no mammalian counterpart. The most interesting of the sea urchin-specific phosphoproteins, from the perspective of biomineralization research, was an abundant highly phosphorylated and very acidic tooth matrix protein composed of 35 very similar short sequence repeats, a predicted N-terminal secretion signal sequence, and an Asp-rich C-terminal motif, contained in [Glean3:18919]. Conclusions The 64 phosphorylation sites determined represent the most comprehensive list of experimentally identified sea urchin protein phosphorylation sites at present and are an important addition to the recently analyzed Strongylocentrotus purpuratus shell and tooth proteomes. The identified phosphoproteins included a major, highly phosphorylated protein, [Glean3:18919], for which we suggest the name phosphodontin. Although not sequence-related to such highly phosphorylated acidic mammalian dental phosphoproteins as phosphoryn or dentin matrix protein-1, phosphodontin may perform similar functions in the sea urchin tooth. More than half of the detected proteins were not previously identified at the protein level, thus confirming the existence of proteins only known as genomic sequences previously.

  13. Effect of tooth bleaching agents on protein content and mechanical properties of dental enamel.

    Science.gov (United States)

    Elfallah, Hunida M; Bertassoni, Luiz E; Charadram, Nattida; Rathsam, Catherine; Swain, Michael V

    2015-07-01

    This study investigated the effect of two bleaching agents, 16% carbamide peroxide (CP) and 35% hydrogen peroxide (HP), on the mechanical properties and protein content of human enamel from freshly extracted teeth. The protein components of control and treated enamel were extracted and examined on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Marked reduction of the protein matrix and random fragmentation of the enamel proteins after bleaching treatments was found. The mechanical properties were analyzed with Vickers indentations to characterize fracture toughness, and nanoindentation to establish enamel hardness, elastic modulus and creep deformation. Results indicate that the hardness and elastic modulus of enamel were significantly reduced after treatment with CP and HP. After bleaching, the creep deformation at maximum load increased and the recovery upon unloading reduced. Crack lengths of CP and HP treated enamel were increased, while fracture toughness decreased. Additionally, the microstructures of fractured and indented samples were examined with field emission gun scanning electron microscopy (FEG-SEM) showing distinct differences in the fracture surface morphology between pre- and post-bleached enamel. In conclusion, tooth bleaching agents can produce detrimental effects on the mechanical properties of enamel, possibly as a consequence of damaging or denaturing of its protein components. PMID:25841347

  14. In-vitro regulation of odontogenic gene expression in human embryonic tooth cells and SHED cells.

    Science.gov (United States)

    Leone, Angelo; Volponi, Ana Angelova; Renton, Tara; Sharpe, Paul T

    2012-06-01

    The bud-to-cap stage transition during early tooth development is a time when the tooth-inducing potential becomes restricted to the mesenchyme. Several key genes, expressed in the mesenchyme at this stage, are an absolute requirement for the progression of tooth development. These include the transcription factors Msx1 and Pax9. The inductive potential of tooth mesenchyme cells is a key requisite for whole-tooth bioengineering and thus identification of cells that can retain this property following expansion in culture is an important as yet unresolved, goal. We show here that in-vitro culture of embryonic human tooth mesenchyme cells and SHED cells express low levels of PAX9 and MSX1 and that these levels can be significantly upregulated by activation of different signalling pathways. Such in-vitro manipulation may thus offer a simple way of maintaining/restoring/inducing the odontogenic-inducing capacity in mesenchymal cells. PMID:22427065

  15. A comparative study of two methods of dental pulp extraction for genetic fingerprinting.

    Science.gov (United States)

    Tilotta, Françoise; Brousseau, Philippe; Lepareur, Elise; Yasukawa, Kazutoyo; de Mazancourt, Philippe

    2010-10-10

    Extracting dental DNA for identification purposes is usually performed after crushing the tooth. The main disadvantage of this method is that the tooth is completely destroyed so further radiographic, anatomical or biochemical studies are no longer possible. We compared the quantities of DNA obtained by crushing the tooth and by removing pulp by standard endodontic access with trepanation of the occlusal surface and amplified DNA micro-satellites. In the series of crushed teeth, insufficient material for amplification was obtained in 78% of cases and a complete profile was obtained in only 9% of cases. Conversely, for the teeth prepared by trepanation, the profile was complete in 75% of cases and the DNA quantity was insufficient in only 3% of cases. Trepanation thus produced superior results in terms of quantity of DNA and the quality of the genetic profiles. Furthermore, it was a conservative procedure that allowed further analyses on the tooth. PMID:20663623

  16. Immunohistochemical Examination for the Distribution of Podoplanin-Expressing Cells in Developing Mouse Molar Tooth Germs

    OpenAIRE

    Imaizumi, Yuri; Amano, Ikuko; Tsuruga, Eichi; Kojima, Hiroshi; Sawa, Yoshihiko

    2010-01-01

    We recently reported the expression of podoplanin in the apical bud of adult mouse incisal tooth. This study was aimed to investigate the distribution of podoplanin-expressing cells in mouse tooth germs at several developing stages. At the bud stage podoplanin was expressed in oral mucous epithelia and in a tooth bud. At the cap stage podoplanin was expressed on inner and outer enamel epithelia but not in mesenchymal cells expressing the neural crest stem cell marker nestin. At the early bell...

  17. Quaternary dating by electron spin resonance (ESR) applied to human tooth enamel

    OpenAIRE

    Carvajal Eduar; Montes Luis; Almanza Ovidio A.

    2011-01-01

    This paper presents the results obtained from using electron paramagnetic resonance (EPR) to analyse tooth enamel found at the Aguazuque archaeological site (Cundinamarca, Colombia), located on the savannah near Bogota at 4° 37' North and 74°17' West. It was presumed that the tooth enamel came from a collective burial consisting of 23 people, involving men, women and children. The tooth enamel was irradiated with gamma rays and the resulting free radicals were measured using an electron spin ...

  18. A model for the molecular underpinnings of tooth defects in Axenfeld–Rieger syndrome

    OpenAIRE

    Li, Xiao; Venugopalan, Shankar R.; Cao, Huojun; Pinho, Flavia O.; Paine, Michael L.; Snead, Malcolm L.; Semina, Elena V; Amendt, Brad A.

    2013-01-01

    Patients with Axenfeld–Rieger Syndrome (ARS) present various dental abnormalities, including hypodontia, and enamel hypoplasia. ARS is genetically associated with mutations in the PITX2 gene, which encodes one of the earliest transcription factors to initiate tooth development. Thus, Pitx2 has long been considered as an upstream regulator of the transcriptional hierarchy in early tooth development. However, because Pitx2 is also a major regulator of later stages of tooth development, especial...

  19. Nano- and micromechanical properties of dentine: investigation of differences with tooth side

    OpenAIRE

    Brauer, Delia S.; Hilton, Joan F; Marshall, Grayson W; Marshall, Sally J.

    2011-01-01

    The soft zone in dentine beneath the dentino-enamel junction is thought to play an important role in tooth function, strain distribution and fracture resistance during mastication. Recently reported asymmetry in mechanical properties with tooth side may point at a basic property of tooth function. The aim of our study was to test if this asymmetry was reflected in the nano- and micromechanical properties of dentine.

  20. Microprocessing of human hard tooth tissues surface by mid-infrared erbium lasers radiation

    Science.gov (United States)

    Belikov, Andrey V.; Shatilova, Ksenia V.; Skrypnik, Alexei V.

    2015-03-01

    A new method of hard tooth tissues laser treatment is described. The method consists in formation of regular microdefects on tissue surface by mid-infrared erbium laser radiation with propagation ratio M2tooth tissues surface before filling for improvement of bond strength between tissues surface and restorative materials, microleakage reduction between tissues surface and restorative materials, and for caries prevention as a result of increasing microhardness and acid resistance of tooth enamel.

  1. Prospective Study of Serum 25-hydroxy Vitamin D and Tooth Loss

    OpenAIRE

    Zhan, Y.; Samietz, S.; Holtfreter, B.; Hannemann, A.; Meisel, P; Nauck, M; Völzke, H.; Wallaschofski, H.; Dietrich, T; Kocher, T.

    2014-01-01

    Vitamin D deficiency and oral diseases (periodontitis, caries, and tooth loss) are highly prevalent in Germany. Previous studies suggested that vitamin D might be a modifiable and protective factor for periodontitis, caries, and tooth loss. However, prospective studies investigating such associations are limited. We explored the association between the concentration of serum 25-hydroxy vitamin D (25OHD) and incidence of tooth loss, progression of clinical attachment loss (CAL) ? 3 mm, and pro...

  2. The Activity of Aspartate Aminotransferase During Canine Retraction (Bodily Tooth Movement) in Orthodontic Treatment

    OpenAIRE

    M.A.W. Rohaya; Z.A. Shahrul Hisham; K. Khazlina

    2008-01-01

    The pattern of activity of aspartate aminotransferase enzyme (AST) following canine distalization stage in orthodontic treatment is being investigated. The enzyme is released to the gingival crevis following tooth movement resulted from focal necrosis in the adjacent periodontal ligament. The finding of enzymatic response could enhance our understanding of the enzyme`s role during tooth movement. This study investigated the potential of AST as a biological marker to monitor tooth moveme...

  3. The action of corticosteroids on orthodontic tooth movement: a literature review

    OpenAIRE

    Luegya Amorim Henriques Knop; Ricardo Lima Shintcovsk; Luciana Borges Retamoso; Ana Maria Trindade Grégio; Orlando Tanaka

    2012-01-01

    INTRODUCTION: Tooth movement is initially characterized by an acute sterile inflammation, followed by sequential multiple reactions in the periodontal ligament in response to biomechanical forces. Pharmacological agents such as corticosteroids may affect the course of orthodontic movement. Scientific studies show antagonistic actions of these drugs on bone resorption during tooth movement. OBJECTIVE: To review the literature about the effect of corticosteroids on orthodontic tooth movement. C...

  4. The Biomechanical Function of Periodontal Ligament Fibres in Orthodontic Tooth Movement

    OpenAIRE

    McCormack, Steven W.; Witzel, Ulrich; Watson, Peter J.; Fagan, Michael J; Gröning, Flora

    2014-01-01

    Orthodontic tooth movement occurs as a result of resorption and formation of the alveolar bone due to an applied load, but the stimulus responsible for triggering orthodontic tooth movement remains the subject of debate. It has been suggested that the periodontal ligament (PDL) plays a key role. However, the mechanical function of the PDL in orthodontic tooth movement is not well understood as most mechanical models of the PDL to date have ignored the fibrous structure of the PDL. In this stu...

  5. Professional and patient-based evaluation of oral rehabilitation in patients with tooth agenesis

    DEFF Research Database (Denmark)

    Dueled, Erik; Gotfredsen, Klaus; Trab Damsgaard, Mogens; Hede, Børge

    2009-01-01

    OBJECTIVES: The outcome of oral rehabilitation is usually monitored with clinical tests rather than by patient's perception of change. The aim of this study was to describe the objective measure and subjective perception of oral rehabilitation in patients with tooth agenesis. MATERIAL AND METHODS: The study included 129 patients with tooth agenesis rehabilitated with implant- or tooth-supported reconstructions, and a control group of 58 patients. Professional assessments included biological, tec...

  6. Apical plug technique in a calcified immature tooth: a case report.

    Science.gov (United States)

    Gujjar, Kumar Raghav; Sharma, Ratika; Amith, H V; Smitha, D; Indushekar, K R

    2015-01-01

    Traumatic injury to an immature tooth may result in pulpal necrosis secondary to pulp canal obliteration, which makes the management of the tooth a clinical challenge for dentists. The present case report describes an innovative apical plug technique with mineral trioxide aggregate in a calcified immature tooth using an ultrasonic tip and long, thin, tapered fissure burs. The technique was proven to be successful clinically and radiographically at 2 years postobturation. PMID:25574727

  7. How to best smash a snail: the effect of tooth shape on crushing load

    OpenAIRE

    Crofts, S. B.; Summers, A. P.

    2014-01-01

    Organisms that are durophagous, hard prey consumers, have a diversity of tooth forms. To determine why we see this variation, we tested whether some tooth forms break shells better than others. We measured the force needed with three series of aluminium tooth models, which varied in concavity and the morphology of a stress concentrating cusp, to break a shell. We created functionally identical copies of two intertidal snail shells: the thicker shelled Nucella ostrina and the more ornamented N...

  8. Radioactive labeling in the study of abrasion of hard tooth tissue

    International Nuclear Information System (INIS)

    Labeling the surface of hard tooth tissue samples by the nuclear recoil effect in radioactive decay was applied to study abrasion caused by abrasive components of tooth-pastes. 222Rn and its short-lived decay products were implanted into the surface in vacuum. For this purpose irradiation was applied to sample placed very close to thin 226Ra source. Measuring the activity before and after abrasion was used to evaluate abrasion in the system toothbrush - various suspensions of the tooth-pastes - hard tooth tissue (enamel or dentine) in a specially designed device, dentoabrasionmeter VUS 2. (author)

  9. Detecting gear tooth fracture in a high contact ratio face gear mesh

    Science.gov (United States)

    Zakrajsek, James J.; Handschuh, Robert F.; Lewicki, David G.; Decker, Harry J.

    1995-01-01

    This paper summarized the results of a study in which three different vibration diagnostic methods were used to detect gear tooth fracture in a high contact ratio face gear mesh. The NASA spiral bevel gear fatigue test rig was used to produce unseeded fault, natural failures of four face gear specimens. During the fatigue tests, which were run to determine load capacity and primary failure mechanisms for face gears, vibration signals were monitored and recorded for gear diagnostic purposes. Gear tooth bending fatigue and surface pitting were the primary failure modes found in the tests. The damage ranged from partial tooth fracture on a single tooth in one test to heavy wear, severe pitting, and complete tooth fracture of several teeth on another test. Three gear fault detection techniques, FM4, NA4*, and NB4, were applied to the experimental data. These methods use the signal average in both the time and frequency domain. Method NA4* was able to conclusively detect the gear tooth fractures in three out of the four fatigue tests, along with gear tooth surface pitting and heavy wear. For multiple tooth fractures, all of the methods gave a clear indication of the damage. It was also found that due to the high contact ratio of the face gear mesh, single tooth fractures did not significantly affect the vibration signal, making this type of failure difficult to detect.

  10. Prevalence of tooth wear among 16-year-old secondary school children in Kota Bharu, Kelantan

    Directory of Open Access Journals (Sweden)

    N.B. Saerah

    2006-09-01

    Full Text Available Tooth wear is the non-carious loss of tooth tissue due to attrition, erosion and/or abrasion. The amount of wear that accelerates physiological tooth wear is referred as pathological tooth wear. This study aims to determine the prevalence and mean scores according to mouth quadrant of raw tooth wear (RTW and pathological tooth wear (PTW and investigate sex association with PTW among 16-year-old secondary school children in Kota Bharu, Kelantan. This cross-sectional study involves 688 participants randomly selected from eight government secondary schools. The Smith and Knight Tooth Wear Index (TWI was used. Data were analyzed using a simplified Microsoft Excel program developed based on the index to quantify PTW. Bar graphs were plotted to highlight the mean scores according to mouth quadrant. About 44% of participants were male and 56% were female. The prevalence of RTW and PTW among subjects was 100% and 20.1% respectively. It was found that 32.8% of tooth surfaces were affected with RTW and 0.7% of study subjects already had exposed dentine. The most affected quadrant for RTW and PTW was the upper and lower incisal quadrant respectively. Males had 92% more odds of developing tooth wear compared to females. In conclusion, all subjects have some degree of wear. About one-fifth of the study subjects were affected by PTW. The patterns of wear were similar to those encountered in the Western societies. There was statistically significant association between sex and PTW.

  11. Dentin sialoprotein: biosynthesis and developmental appearance in rat tooth germs in comparison with amelogenins, osteocalcin and collagen type-I.

    Science.gov (United States)

    Bronckers, A L; D'Souza, R N; Butler, W T; Lyaruu, D M; van Dijk, S; Gay, S; Wöltgens, J H

    1993-05-01

    A non-collagenous protein, extracted from rat incisor dentin, is a dentin sialoprotein (DSP). We examined immunohistochemically the developmental appearance and tissue distribution of DSP in 1 to 3-day-old rat molar and incisor tooth germs. The earliest staining for DSP was observed in newly differentiated odontoblasts. In more advanced stages, immunostaining for DSP gradually increased in pre-dentin, odontoblasts and dentin, and appeared in many cells of the dental papilla. In early stages of development before the breakdown of the dental basement membrane, pre-ameloblasts were also positive for DSP. This staining disappeared from the ameloblast cell body soon after deposition of the first layer of mineralized dentin. Radiolabelling of tooth matrix proteins with 14C-serine in vitro followed by immunoprecipitation and fluorography confirmed that DSP was synthesized by tooth-forming cells. The immunolocalization for DSP was different from that of either collagen type-I, osteocalcin or the amelogenins. Whereas collagen type-I and osteocalcin were restricted to the mesenchymal dental tissues, the amelogenins were detectable in both epithelial and mesenchymal dental cells and tissues at the epithelio-mesenchymal interface at early stages of development, prior to the onset of dentin mineralization. We conclude that DSP is expressed in and secreted by odontoblasts and some dental papilla cells from early stages of dentinogenesis onwards, i.e. later than type-I collagen, but before deposition of the first layer of mineralized dentin. In pre-mineralizing stages, some of the matrix proteins may be endocytosed from the pre-dentin by both cell types involved in the epithelio-mesenchymal interaction. PMID:8513478

  12. Comparison of hard tissue interrelationships at the cervical region of teeth based on tooth type and gender difference

    Directory of Open Access Journals (Sweden)

    Madhusudan Astekar

    2014-01-01

    Full Text Available Context: Cementoenamel junction (CEJ represents the anatomic limit between the crown and root surface. With advancing age and continuous eruption, this area becomes exposed in the oral media. Consequently, CEJ will be subjected to the action of various physical and chemical factors that might alter its morphology, with the cementum being affected in most cases. Aim: To identify the frequency of hard tissue interrelationships present at the CEJ in relation to different genders, positions and aspects of tooth using a light microscope. Materials and Methods: The cervical regions of 80 permanent teeth (40 male and 40 female, extracted for orthodontic or periodontal reasons, were analyzed after longitudinal ground sections were made in the mesio-distal plane. The CEJ of the prepared sections was then studied and their frequencies were categorized as: cementum overlapping enamel, enamel overlapping cementum, edge-to-edge relationship and the presence of gap junctions. Statistical Analysis: Chi-square test performed using SPSS 15 software. Results: Edge-to-edge contact of the cementum and enamel was most frequent, followed by gap junction and cementum overlapping the enamel, respectively. Chi-square test revealed no statistically significant differences with respect to the gender and tooth aspect, whereas the result was significant when the position of the tooth was studied. Conclusion: The observations of the study indicate a considerable morphological diversity in the anatomical pattern of CEJ. It can be concluded that the region should be protected against dentinal sensitivity, erosion, abrasion, abfraction and resorption, as it is more prone to cervical pathologies.

  13. A 3-year prospective study of implant-supported, single-tooth restorations of all-ceramic and metal-ceramic materials in patients with tooth agenesis

    DEFF Research Database (Denmark)

    Hosseini, Mandana; Worsaae, Nils; Schiødt, Morten; Gotfredsen, Klaus

    2013-01-01

    OBJECTIVES: The purpose of this clinical study was to describe outcome variables of all-ceramic and metal-ceramic implant-supported, single-tooth restorations. MATERIALS AND METHODS: A total of 59 patients (mean age: 27.9 years) with tooth agenesis and treated with 98 implant-supported single-tooth restorations were included in this study. Two patients did not attend baseline examination, but all patients were followed for 3 years. The implants supported 52 zirconia, 21 titanium and 25 gold allo...

  14. First record of a white rough-toothed dolphin (Steno bredanensis) off West Africa including notes on rough-toothed dolphin surface behaviour

    OpenAIRE

    Boer, M.N., de

    2010-01-01

    In June 2009, a white rough-toothed dolphin (Steno bredanensis) calf was photographed in a group of at least 50 dolphins in the southern Gulf of Guinea, 95 nauticol miles off the Gabon coast (01°45?S 007°29?E), West Africa. Reports of unusually pigmented cetaceans are infrequent and this record represents the first of an all-white rough-toothed dolphin. Furthermore, there is little documentation concerning rough-toothed dolphins and this note contributes to the knowledge of this species in tr...

  15. The second international intercomparison on EPR tooth dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Wieser, A. E-mail: wieser@gsf.de; Mehta, K.; Amira, S.; Aragno, D.; Bercea, S.; Brik, A.; Bugai, A.; Callens, F.; Chumak, V.; Ciesielski, B.; Debuyst, R.; Dubovsky, S.; Duliu, O.G.; Fattibene, P.; Haskell, E.H.; Hayes, R.B.; Ignatiev, E.A.; Ivannikov, A.; Kirillov, V.; Kleschenko, E.; Nakamura, N.; Nather, M.; Nowak, J.; Onori, S.; Pass, B.; Pivovarov, S.; Romanyukha, A.; Scherbina, O.; Shames, A.I.; Sholom, S.; Skvortsov, V.; Stepanenko, V.; Tikounov, D.D.; Toyoda, S

    2000-12-15

    Eighteen international EPR laboratories participated in the second intercomparison programme. Each participant had to prepare enamel samples and evaluate the absorbed dose from molars that were irradiated in vitro in the range 0-1000 mGy. The objective of the programme was to bring together all methods which are currently applied by different laboratories for EPR dose reconstruction and to demonstrate the present state of dosimetry. An overview of the essential features of the different methods is presented. The current accuracy of EPR tooth enamel dosimetry under defined conditions of irradiation is evaluated.

  16. The second international intercomparison on EPR tooth dosimetry

    International Nuclear Information System (INIS)

    Eighteen international EPR laboratories participated in the second intercomparison programme. Each participant had to prepare enamel samples and evaluate the absorbed dose from molars that were irradiated in vitro in the range 0-1000 mGy. The objective of the programme was to bring together all methods which are currently applied by different laboratories for EPR dose reconstruction and to demonstrate the present state of dosimetry. An overview of the essential features of the different methods is presented. The current accuracy of EPR tooth enamel dosimetry under defined conditions of irradiation is evaluated

  17. Tooth mortality in an adult rural population in Kenya

    DEFF Research Database (Denmark)

    Manji, F; Baelum, V; Fejerskov, O

    1988-01-01

    This paper reports on the pattern of tooth loss in a random sample of 1131 adults aged from 15 to 65 years in a rural area of Kenya in which access to formal dental care is minimal. We found that the majority of the population retained most of their dentition in a functional state even up to the age of 65 years: In all age groups, more than 50% had at least 26 teeth present, and more than 90% had at least 16 teeth present. The prevalence of edentulousness was less than 0.3%. The principal cause ...

  18. Posteruptive tooth age and severity of dental fluorosis in Kenya

    DEFF Research Database (Denmark)

    Baelum, V; Manji, F; Fejerskov, O

    1986-01-01

    The purpose of the present study was to assess whether the degree of severity of enamel changes in a population exhibiting rather severe dental fluorosis may be related to posteruptive tooth age and to describe the clinical manifestations of the enamel destructions. All permanent teeth in 102 children aged 10-15 yr who were born and reared in a 2 ppm fluoride area of Kenya were examined for dental fluorosis using the TF-Index. Clinically, at time of eruption all teeth appeared chalky white, but ...

  19. Inversion voltammeter definition of heavy metals in tooth pastes

    International Nuclear Information System (INIS)

    Electrochemical behaviour of some heavy metals at their combined presence is studied by voltammetric method with use of graphite content sensor. The method of determination of Hg, Pb, Cd, Cu, and Zn in the tooth pastes, based on transfer of hallmark in a solution and voltammeter diagram registration is developed. Duration of the analysis (3 collateral hallmarks) makes no more than 1.5 h. An error - 10-15 % at the contents of determined elements of the (1-5) x 10-4 %

  20. The origin of remarkable resilience of human tooth enamel

    Science.gov (United States)

    Zhao, Xiaoli; O'Brien, Simona; Shaw, Jeremy; Abbott, Paul; Munroe, Paul; Habibi, Daryoush; Xie, Zonghan

    2013-12-01

    The mechanical properties of human tooth enamel depend not only on test locations but also on the indentation depth. However, it remains uncertain what roles the depth-dependant properties play in mechanical performance of enamel. Here we reveal that a change in the mechanical properties of enamel, in particular its strength, with increasing indentation depth promotes inelastic deformation in material. In doing so, the severity and extent of stress concentration is reduced. Furthermore, we observed that following unloading, self-recovery occurs in enamel. These findings improve our understanding of the underlying mechanisms responsible for the remarkable resilience of enamel.

  1. Manufacture of Toothed Elements in Nanoausferritic Ductile Iron

    Directory of Open Access Journals (Sweden)

    Myszka D.

    2014-10-01

    Full Text Available The technology currently used for the fabrication of toothed wheels, gear couplings and chain drums involves the induction hardening process or hardening and tempering after carburising. All these processes take a long time and cause adverse changes in the dimensions and surface quality of products, requiring post-treatment machining to remove the resulting cavities. The paper proposes the implementation of gear elements made of ductile iron with nanoausferritic matrix obtained by a new appropriate heat treatment process. The new material offers good performance characteristics and nearly no need for the application of other technological processes commonly used in the manufacture of gears.

  2. Charcot-Marie-Tooth disease complicating type 2 diabetes.

    LENUS (Irish Health Repository)

    Win, Htet Htet Ne

    2012-02-01

    Although both conditions are relatively common, there are very few descriptions of type 2 diabetes mellitus coexisting with Charcot-Marie-Tooth disease (CMT). This case report and literature review describes a 53-year-old Irish man who presented with type 2 diabetes and significant neuropathy, and who was subsequently diagnosed with CMT type 1A. This case report will also discuss how to differentiate diabetic neuropathy from a progressive hereditary neuropathy and how coexistence aggravates the progression of neuropathy thus necessitating early diagnosis.

  3. Charcot-marie-tooth disease complicating type 2 diabetes.

    LENUS (Irish Health Repository)

    Win, Htet Htet Ne

    2011-07-01

    Although both conditions are relatively common, there are very few descriptions of type 2 diabetes mellitus coexisting with Charcot-Marie-Tooth disease (CMT). This case report and literature review describes a 53-year-old Irish man who presented with type 2 diabetes and significant neuropathy, and who was subsequently diagnosed with CMT type 1A. This case report will also discuss how to differentiate diabetic neuropathy from a progressive hereditary neuropathy and how coexistence aggravates the progression of neuropathy thus necessitating early diagnosis.

  4. The Gap-Tooth Method in Particle Simulations

    CERN Document Server

    Gear, C W; Kevrekidis, Yu G; Li, Ju; Kevrekidis, Ioannis G.

    2003-01-01

    We explore the gap-tooth method for multiscale modeling of systems represented by microscopic physics-based simulators, when coarse-grained evolution equations are not available in closed form. A biased random walk particle simulation, motivated by the viscous Burgers equation, serves as an example. We construct macro-to-micro (lifting) and micro-to-macro (restriction) operators, and drive the coarse time-evolution by particle simulations in appropriately coupled microdomains (teeth) separated by large spatial gaps. A macroscopically interpolative mechanism for communication between the teeth at the particle level is introduced. The results demonstrate the feasibility of a closure-on-demand approach to solving hydrodynamics problems.

  5. Tooth-surface-specific Effects of Xylitol: Randomized Trial Results

    OpenAIRE

    Ritter, A.V.; Bader, J.D.; Leo, M. C.; Preisser, J.S.; Shugars, D.A.; Vollmer, W.M.; Amaechi, B.T.; Holland, J.C.

    2013-01-01

    The Xylitol for Adult Caries Trial was a three-year, double-blind, multi-center, randomized clinical trial that evaluated the effectiveness of xylitol vs. placebo lozenges in the prevention of dental caries in caries-active adults. The purpose of this secondary analysis was to investigate whether xylitol lozenges had a differential effect on cumulative caries increments on different tooth surfaces. Participants (ages 21-80 yrs) with at least one follow-up visit (n = 620) were examined at base...

  6. Radicular cyst of primary tooth associated with maxillary sinus

    OpenAIRE

    Rakesh N. Bahadure; Khubchandani, Monika; Thosar, Nilima R; Rajeev Kumar SINGH

    2013-01-01

    Radicular cyst is one of the most common odontogenic cystic lesions found in the jaws. It is inflammatory in nature and found mostly in relation to a non-vital tooth. It usually presents at a later stage in life because the formation of the cyst is the last step in the progression of inflammatory events after a periapical infection. The cyst usually goes unnoticed because of its painless nature and small size. We present the clinical, radiographic and histological characteristics of a radicul...

  7. Benign Cementoblastoma associated with a deciduous tooth: a case report

    Directory of Open Access Journals (Sweden)

    Hemant R Umarji

    2011-10-01

    Full Text Available Benign Cementoblastoma is an odontogenic neoplasm of cementoblasts, also known as true cementoma. Cementoblastoma rarely affects the deciduous teeth and its occurrence on the left side is much more uncommon. This case report is of a 13 year-old patient who presented with cementoblastoma associated with a deciduous second molar in the mandible. The objective of this case report is to add one more case of this rare odontogenic tumor to the academic literature. Key Words: Benign Cementoblastoma, odontogenic tumor, deciduous tooth

  8. Three-dimensional analysis of mandibular growth and tooth eruption

    DEFF Research Database (Denmark)

    Krarup, S.; Darvann, Tron Andre

    2005-01-01

    Normal and abnormal jaw growth and tooth eruption are topics of great importance for several dental and medical disciplines. Thus far, clinical studies on these topics have used two-dimensional (2D) radiographic techniques. The purpose of the present study was to analyse normal mandibular growth and tooth eruption in three dimensions based on computer tomography (CT) scans, extending the principles of mandibular growth analysis proposed by Bjork in 1969 from two to three dimensions. As longitudinal CT data from normal children are not available (for ethical reasons), CT data from children with Apert syndrome were employed, because it has been shown that the mandible in Apert syndrome is unaffected by the malformation, and these children often have several craniofacial CT scans performed during childhood for planning of cranial and midface surgery and for follow-up after surgery. A total of 49 datasets from ten children with Apert syndrome were available for study. The number of datasets from each individual ranged from three to seven. The first CT scan in each of the ten series was carried out before 1 year of age, and the ages for the 49 scans ranged from 1 week to 14.5 years. The mandible and the teeth were segmented and iso-surfaces generated. Landmarks were placed on the surface of the mandible, along the mandibular canals, the inner contour of the cortical plate at the lower border of the symphysis menti, and on the teeth. Superimposition of the mandibles in the longitudinal series was performed using the symphysis menti and the mandibular canals as suggested by Bjork. The study supported the findings of stability of the symphysis menti and the mandibular canals as seen in profile view previously reported by Bjork & Skieller in 1983. However, the mandibular canals were, actually, relocated laterally during growth. Furthermore, the position of tooth buds remained relatively stable inside the jaw until root formation started. Eruption paths of canines and premolars were vertical, whereas molars erupted in a lingual direction. The 3D method would seem to offer new insight into jaw growth and tooth eruption, but further studies are needed.

  9. Charcot-Marie-Tooth Disease: Seventeen Causative Genes

    OpenAIRE

    Lee, Jung-Hwa; Choi, Byung-Ok

    2006-01-01

    Charcot-Marie-Tooth disease (CMT) is the most common form of inherited motor and sensory neuropathy. Moreover, CMT is a genetically heterogeneous disorder of the peripheral nervous system, with many genes identified as CMT-causative. CMT has two usual classifications: type 1, the demyelinating form (CMT1); and type 2, the axonal form (CMT2). In addition, patients are classified as CMTX if they have an X-linked inheritance pattern and CMT4 if the inheritance pattern is autosomal recessive. A l...

  10. Smoking, Smoking Cessation, and Risk of Tooth Loss: The EPIC-Potsdam Study.

    Science.gov (United States)

    Dietrich, T; Walter, C; Oluwagbemigun, K; Bergmann, M; Pischon, T; Pischon, N; Boeing, H

    2015-10-01

    The aim of this study was to investigate the association between cigarette smoking and smoking cessation and the prevalence and incidence of tooth loss in a large cohort study in Germany. We analyzed data of 23,376 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study recruited between 1994 and 1998 from the general population in Potsdam and other parts of Brandenburg, Germany, who had complete data on cigarette smoking, tooth loss, and covariates. Negative binomial regression and tooth-specific logistic regression models were fit to evaluate the association between smoking and the baseline prevalence and incidence of tooth loss during follow-up, respectively. Cigarette smoking was associated with higher prevalence of tooth loss at baseline as well as higher incidence of tooth loss during follow-up. The association between smoking and the incidence of tooth loss was stronger in men than women and stronger in younger versus older individuals. Heavy smoking (?15 cigarettes/d) was associated with >3 times higher risk of tooth loss in men (odds ratio, 3.6; 95% confidence interval, 3.0, 4.4) and more than twice the risk of tooth loss in women (odds ratio, 2.5; 95% confidence interval, 2.1, 2.9) younger than 50 y when compared with never smokers. Smoking cessation was consistently associated with a reduction in tooth loss risk, with the risk of tooth loss approaching that of never smokers after approximately 10 to 20 y of cessation. PMID:26243734

  11. Analysis of stress state of toothed ring of flexspline by means the BEM

    Directory of Open Access Journals (Sweden)

    P. Fol?ga

    2013-01-01

    Full Text Available Purpose: The paper presents an analysis of the influence of design features of the flexspline in a harmonic drive, such as the relative radial deformation, the relative coating thickness and the design features of the basic rack tooth profile, on stress values in the bottom lands of a toothed ring.Design/methodology/approach: In numerical calculations, the software developed at the Faculty of Transport of the Silesian University of Technology was used. The program automatically generates a profile of the flexspline and a boundary elements mesh on the grounds of the flexspline and working tool assigned parameters. In the analysis of the state of stress, the boundary element method (BEM was applied.Findings: A decreased value of the curve radius of the head of the basic rack tooth profile results in a change in the width of the tooth bottom land, shortening of the transition curve in the tooth base and a reduction of the tooth thickness at its base, which in turn leads to increased values of stress. Yet, the influence of the relative curve radius of the head of the basic rack tooth profile on the stress value is insignificant. The increase of the torque and relative coating thickness for different value of the curve radius of the head of the basic rack tooth profile cause an increase of stress in the bottom lands of the toothed ring.Research limitations/implications: The paper presents strength calculations for the teeth in toothed ring of a flexspline of a double harmonic drive by means of boundary elements method (BEM. The results of numerical calculations correspond in terms of their quality to the results presented in the literature, which were calculated by finite element method (FEM.Originality/value: In the analysis of the state of stress of toothed ring of flexspline, the boundary element method (BEM was applied.

  12. Effect of bisphosphonates on orthodontic tooth movement-an update.

    Science.gov (United States)

    Krishnan, Sindhuja; Pandian, Saravana; Kumar S, Aravind

    2015-04-01

    Bisphosphonates are a synthetic class of pyrophosphate analogues that are powerful inhibitors of bone resorption which are commonly used as a medication for the prevention and therapy of osteoporosis and osteopenia, also used to treat tumor diseases. As it affects bone metabolism, it is said to have an influence on orthodontic treatment and tooth movement. Also, this review gives an insight into the reported effects of Bisphosphonate medication in literature highlighting the status quo of scientific research regarding effects of Bisphosphonates on orthodontic tooth movement. A systematic literature search was done in Medline database (Pubmed) for the appropriate keywords. Manual handsearch was also done. From the available evidence it can be concluded that the duration of orthodontic treatment is increased for patients under Bisphosphonate therapy as they interfere with the osteoclastic resorption. However, they may be beneficial for anchorage procedures. Further long term prospective randomized controlled trials are required to assess possible benefits and adverse effects of bisphosphonate treatment, before Bisphosphonates can be therapeutically used in orthodontics. PMID:26023659

  13. The unicorn and the narwhal: a tale of the tooth.

    Science.gov (United States)

    Christen, Arden G; Christen, Joan A

    2011-01-01

    From as far back as the early Roman era, detailed descriptions and artistic images of the unicorn have been imagined. In Europe, the Mediterranean and the Far East, this creature became accepted as real. Although such an animal had never actually been seen, it was said to have the appearance of a horse, the beard and cloven hooves of a goat, the tail of a lion, and a single, spear-like horn protruding from the center of its forehead. The unicorn myth originated shortly after unidentified horn-like objects, from six to ten feet long, began to appear in ancient European marketplaces. Physicians quickly ascribed outlandish healing properties to these horns, pulverizing them for the treatment of various diseases. In 1638, a Danish zoologist challenged these claims and provided evidence that the so-called "unicorn horn" was actually the tusk (tooth) of the narwhal from the Arctic seas. However, his findings remained unheeded for the next 100 years. This paper explains how the myth of the unicorn and the purported powers contained within the substance of its magical horn evolved from the ages-old spoils of the Arctic fishing trade, where the narwhal was primarily speared for food and secondarily, for the export value of its ivory tusk. This unusually long, pointed and protruding single tooth, which breaks through the upper lip and the left jaw of each male narwhal, became a highly valuable commodity over the following centuries, due to its believed supernatural origins and curative qualities. PMID:22372187

  14. Disturbed tooth formation by 60Co-gamma-ray radiation

    International Nuclear Information System (INIS)

    The molar of guinea pigs was irradiated with 60Co-#betta# ray for daily observations of the manifestation of disturbed tooth formation by microradiography and the time registration by tetracycline-labelling. Irradiation first injured young blast cells of the dentin in the growth phase, dental pulp cells, and cells of the enamel. The portion composed of injured cells formed a depressed ''constriction'' from the dental pulp side toward the border between the enamel and dentin. The cells of the enamel injured by irradiation in the growth phase later formed a very thin irregular stroma. In contrast, cells in the differentiation or subsequent phase at the time of irradiation and cells probably having started to grow after irradiation proceeded with formation of a normal stroma and calcification. No uniform relation was obtained between the histological staining of the organic stroma of normal or abnormal dentin and calcification. Labelling with tetracycline revealed that the irradiation conditions in the present study provoked hardly any changes in the speed of tooth eruption. (Chiba, N.)

  15. T Cells Are Required for Orthodontic Tooth Movement.

    Science.gov (United States)

    Yan, Y; Liu, F; Kou, X; Liu, D; Yang, R; Wang, X; Song, Y; He, D; Gan, Y; Zhou, Y

    2015-10-01

    The immune system plays a pivotal role during bone remodeling process. Orthodontic tooth movement (OTM) induces local inflammation in periodontium, but whether systemic immune response is involved in OTM remains unknown. In this study, we show that tooth movement distance was significantly reduced in T-cell-deficient immunocompromised mice compared with wild-type (WT) mice. Intravenous infusion of allogeneic T cells to the immunocompromised mice rescued the OTM distance. Correspondingly, increased numbers of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts were detected around the alveolar bone after OTM in WT mice but were barely detected in immunocompromised mice. Moreover, intravenous infusion of T cells rescued the number of TRAP-positive osteoclasts in the OTM area of the immunocompromised mice, thus suggesting T cells are required for OTM. We then reveal that OTM induced a significant elevation of type 1 T helper cell (Th1) cytokines tumor necrosis factor-? (TNF-?) and interferon-? (IFN-?) around periodontal tissue in WT but not in immunocompromised mice. Infusion of T cells could increase the levels of TNF-? and IFN-? in periodontal tissues of immunocompromised mice. More interestingly, intraperitoneal injection of TNF-? inhibitor etanercept significantly reduced the distance of OTM in T-cell-infused immunocompromised mice. In summary, this study demonstrates a previously unrecognized mechanism that T cells are required for OTM depending on Th1-associated cytokines. PMID:26187644

  16. Viscoplastic response of tooth enamel under cyclic microindentation.

    Science.gov (United States)

    Jia, Yunfei; Xuan, Fu-Zhen; Yang, Fuqian

    2015-10-01

    Cyclic microindentations were performed on the occlusal surface and axial section of tooth enamel, using the Berkovich indenter. Under the action of a cyclic indentation load, the indenter continuously penetrated into the tooth enamel and reached a quasi-steady state at which the penetration depth per cycle was a constant. At the quasi-steady state, both the amplitude of the indentation depth and the penetration depth per cycle for the cyclic indentation of the axial section are larger than those for the indentation of the occlusal section under the same loading condition. The energy dissipation per cycle consists of two contributions; one is the plastic energy dissipated per cycle due to the propagation of the plastic zone underneath the indentation and the other is the energy dissipation due to the viscous flow during the cyclic indentation. Both the penetration depth and the plastic energy dissipated per cycle at the quasi-steady state are independent of the maximum applied load and increase with increasing the amplitude of the cyclic indentation load. PMID:26117776

  17. Novel PAX9 mutation associated with syndromic tooth agenesis.

    Science.gov (United States)

    Mostowska, Adrianna; Zadurska, Ma?gorzata; Rakowska, Adriana; Lianeri, Margarita; Jagodzi?ski, Pawe? P

    2013-10-01

    Tooth agenesis is the most common anomaly of dental development. The purpose of the present study was to identify the causative mutation(s) in a family with a syndromic form of hypodontia. The male proband lacked 19 permanent teeth and showed defects of hair, but lacked ectodermal symptoms of skin and nails. Direct sequencing of the coding regions, including exon/intron boundaries of the msh homeobox 1 (MSX1), paired box 9 (PAX9), ectodysplasin A (EDA), and wingless-type MMTV integration site family, member 10 (WNT10A) genes, was carried out in affected family members. All identified nucleotide variations were tested in 200 healthy individuals using high-resolution melting (HRM) curve analysis to exclude the possibility that they represent rare polymorphisms. A novel heterozygous c.59delC mutation, segregating in the autosomal-dominant model, was identified in the PAX9 gene of the proband and the family members studied. This one-nucleotide deletion, located in a highly conserved paired box sequence, resulted in a frameshift (p.Pro20Argfs65) and in premature termination of translation, yielding a truncated protein 258 amino acids shorter than the wildtype protein. No pathogenic mutations were found in the MSX1, EDA, and WNT10A genes. In conclusion, the novel PAX9 deletion might be responsible for tooth agenesis and trichodysplasia in the investigated family. This c.59delC mutation potentially leads to PAX9 transcription factor haploinsufficiency. PMID:24028587

  18. Hippo pathway/Yap regulates primary enamel knot and dental cusp patterning in tooth morphogenesis.

    Science.gov (United States)

    Kwon, Hyuk-Jae Edward; Li, Liwen; Jung, Han-Sung

    2015-11-01

    The shape of an individual tooth crown is primarily determined by the number and arrangement of its cusps, i.e., cusp patterning. Enamel knots that appear in the enamel organ during tooth morphogenesis have been suggested to play important roles in cusp patterning. Animal model studies have shown that the Hippo pathway effector Yap has a critical function in tooth morphogenesis. However, the role of the Hippo pathway/Yap in cusp patterning has not been well documented and its specific roles in tooth morphogenesis remain unclear. Here, we provide evidence that Yap is a key mediator in tooth cusp patterning. We demonstrate a correlation between Yap localization and cell proliferation in developing tooth germs. We also show that, between the cap stage and bell stage, Yap is crucial for the suppression of the primary enamel knot and for the patterning of secondary enamel knots, which are the future cusp regions. When Yap expression is stage-specifically knocked down during the cap stage, the activity of the primary enamel knot persists into the bell-stage tooth germ, leading to ectopic cusp formation. Our data reveal the importance of the Hippo pathway/Yap in enamel knots and in the proper patterning of tooth cusps. PMID:26318014

  19. Evaluation of the effectiveness of the tooth whitening treatment associated with the immersion in coloring solutions

    Directory of Open Access Journals (Sweden)

    Giovani de Oliveira Correa

    2012-12-01

    Full Text Available Introduction: Tooth whitening or dental bleaching is a cosmetic procedure that has established itself in Dentistry; however, the staining because of the ingestion of some types of food may cause several factors leading to the failure of this treatment. Objective: This study aimed to evaluate in vitro the influence of the immersion of whitened teeth in solutions with a high degree of pigmentation on the efficacy of the bleaching performed with 16% hydrogen peroxide. Material and methods: Fifty-six human teeth were selected, bleached for 4 hours a day during 14 days and randomly divided into 7 groups (n = 8. The groups G1/G2 and G3 were immersed in coloring solutions immediately (IM after bleaching (AP: G1 – tooth whitening + coffee (IM, G2 – tooth whitening + cola-based soft drink (IM and G3 – tooth whitening + red wine (IM; G4/and G6 were immersed in the solutions for 2 hours (AP, G4 – tooth whitening + coffee (AP, G5 – tooth whitening + cola based soft drink (AP, G6 – tooth whitening + red wine and (AP G7 – control. After bleaching with an immersion time of 5 minutes, with the aid of a digital spectrophotometer, the final color (FC was measured 24 hours after the end of the bleaching treatment (day 15. Results: The results for ANOVA showed no statistical differences in all groups. Conclusion: There was no influence on the effectiveness of tooth whitening immersed in coloring solutions.

  20. Histochemical examination of cathepsin K, MMP1 and MMP2 in compressed periodontal ligament during orthodontic tooth movement in periostin deficient mice.

    Science.gov (United States)

    Lv, Shengyu; Liu, Hongrui; Cui, Jian; Hasegawa, Tomoka; Hongo, Hiromi; Feng, Wei; Li, Juan; Sun, Bao; Kudo, Akira; Amizuka, Norio; Li, Minqi

    2014-06-01

    The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo's method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application. PMID:24202437

  1. Treatment of asymptomatic internal resorption of a maxillary premolar tooth in a military working dog.

    Science.gov (United States)

    Eikenberg, S; Loheide, H; Arens, F C

    1998-12-01

    An asymptomatic pink discoloration of a maxillary right fourth premolar tooth was discovered during a routine oral examination on a 9 year-old Belgian Malinois dog. A radiolucent lesion was seen in the pulpal chamber on radiographic examination. The lesion had perforated the mesiobuccal root of the tooth. The primary differential diagnosis was idiopathic internal resorption. The tooth was treated by partial resection (removal of the mesiobuccal root and associated crown). A vital pulpotomy and amalgam restoration was performed on the remaining tooth structure. A follow-up 1 year later demonstrated a successful treatment outcome. The animal was asymptomatic and able to perform military duties. Clinical and radiographic signs of healing were evident and the tooth was functional. PMID:10518874

  2. Retrospective dosimetry assessment using the 380 deg. C thermoluminescence peak of tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Secu, C.E. [National Institute for Materials Physics, PO Box MG-7, 77125 Bucharest-Magurele (Romania); Cherestes, M. [Dozimed Ltd., Dosimetry Laboratory, 77125 Bucharest-Magurele (Romania); Secu, M., E-mail: msecu@infim.ro [National Institute for Materials Physics, PO Box MG-7, 77125 Bucharest-Magurele (Romania); Cherestes, C.; Paraschiva, V. [Dozimed Ltd., Dosimetry Laboratory, 77125 Bucharest-Magurele (Romania); Barca, C. [Faculty of Physics, University of Bucharest, 77125 Bucharest-Magurele (Romania)

    2011-10-15

    The thermoluminescence (TL) response to gamma-ray irradiation of tooth enamel is reported. The tooth enamel was separated from dentine by using mechanical and physico-chemical procedures followed by grinding (grain size {approx}100 {mu}m) and etching. The TL was attributed to the recombination of CO{sub 2}{sup -} radicals incorporated into or attached to the surface of hydroxyapatite crystals. The growth of the {approx}380 deg. C TL peak with absorbed dose was examined with irradiated tooth enamel samples and reconstructed doses evaluated for tooth enamel samples from four human subjects. - Highlights: > Thermoluminescence response after gamma-ray irradiation of tooth enamel was investigated. > Thermoluminescence was attributed to the recombination of CO{sub 2}{sup -} radicals. > CO{sub 2}{sup -} radicals are produced inside or at the surface of hydroxyapatite crystals. > From the growth of the 380C peak reconstructed doses have been evaluated.

  3. Uneven distribution of enamel in the tooth crown of a Plains Zebra (Equus quagga).

    Science.gov (United States)

    Winkler, Daniela E; Kaiser, Thomas M

    2015-01-01

    Unworn teeth of herbivorous mammals are not immediately functional. They have to be partially worn to expose enamel ridges which can then act as shear-cutting blades to break the food down. We use the Plains Zebra (Equus quagga) as a hypsodont, herbivorous model organism to investigate how initial wear of the tooth crown is controlled by underlying structures. We find that the enamel proportion is smaller at the apical half of the tooth crown in all upper tooth positions and suggest that lower enamel content here could promote early wear. Besides this uneven enamel distribution, we note that the third molar has a higher overall enamel content than any other tooth position. The M3 is thus likely to have a slightly different functional trait in mastication, resisting highest bite forces along the tooth row and maintaining functionality when anterior teeth are already worn down. PMID:26082860

  4. Uneven distribution of enamel in the tooth crown of a Plains Zebra (Equus quagga

    Directory of Open Access Journals (Sweden)

    Daniela E. Winkler

    2015-06-01

    Full Text Available Unworn teeth of herbivorous mammals are not immediately functional. They have to be partially worn to expose enamel ridges which can then act as shear-cutting blades to break the food down. We use the Plains Zebra (Equus quagga as a hypsodont, herbivorous model organism to investigate how initial wear of the tooth crown is controlled by underlying structures. We find that the enamel proportion is smaller at the apical half of the tooth crown in all upper tooth positions and suggest that lower enamel content here could promote early wear. Besides this uneven enamel distribution, we note that the third molar has a higher overall enamel content than any other tooth position. The M3 is thus likely to have a slightly different functional trait in mastication, resisting highest bite forces along the tooth row and maintaining functionality when anterior teeth are already worn down.

  5. On optimization of internal/external spur gears tooth bending strength

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2014-01-01

    Gear fatigue strength is primarily controlled by the durability and load capacity, the first is typically related to pitting damage and the second to tooth-breakage. The pitting is due to the tooth contact and the shape of the contacting surfaces, the tooth breakage is controlled by the stress level at the tooth root. As with most machine elements the design/geometry is defined in standards (ISO). The present work focuses on changing the tooth root design of both external and internal gears, in order to improve the stress concentration factor. The design changes made are compliant with the standard, i.e. the optimized gear design can mesh with a standard gear.

  6. Organ dose conversions from ESR measurements using tooth enamel of atomic bomb survivors

    International Nuclear Information System (INIS)

    Dose conversions were studied for dosimetry of atomic bomb survivors based upon electron spin resonance (ESR) measurements of tooth enamel. Previously analysed data had clarified that the tooth enamel dose could be much larger than other organ doses from a low-energy photon exposure. The radiation doses to other organs or whole-body doses, however, are assumed to be near the tooth enamel dose for photon energies which are dominant in the leakage spectrum of the Hiroshima atomic bomb assumed in DS02. In addition, the thyroid can be a candidate for a surrogate organ in cases where the tooth enamel dose is not available in organ dosimetry. This paper also suggests the application of new Japanese voxel phantoms to derive tooth enamel doses by numerical analyses. (authors)

  7. Retrospective dosimetry assessment using the 380 deg. C thermoluminescence peak of tooth enamel

    International Nuclear Information System (INIS)

    The thermoluminescence (TL) response to gamma-ray irradiation of tooth enamel is reported. The tooth enamel was separated from dentine by using mechanical and physico-chemical procedures followed by grinding (grain size ?100 ?m) and etching. The TL was attributed to the recombination of CO2- radicals incorporated into or attached to the surface of hydroxyapatite crystals. The growth of the ?380 deg. C TL peak with absorbed dose was examined with irradiated tooth enamel samples and reconstructed doses evaluated for tooth enamel samples from four human subjects. - Highlights: ? Thermoluminescence response after gamma-ray irradiation of tooth enamel was investigated. ? Thermoluminescence was attributed to the recombination of CO2- radicals. ? CO2- radicals are produced inside or at the surface of hydroxyapatite crystals. ? From the growth of the 380C peak reconstructed doses have been evaluated.

  8. Relationship between human tooth enamel free radical concentration and radiation dose

    International Nuclear Information System (INIS)

    Free radical concentrations of 25 adult tooth enamel samples were measured by electron spin resonance (ESR) technique in this paper, and the relationship between free radical concentration of tooth enamel and radiation dose was also investigated. In the 25 adult enamel samples they are 16 male samples and 9 female samples, Ages of tooth donors range from 18-41 years. Difference in background ESR signal intensity between male and female samples was no observed; free radical concentration (or increment of radiation-induced free radical concentration) in tooth enamel increases linearly with increasing of radiation dose. In the case of radiation accident, the study results of this paper could be applied to dose estimation when conditions of ESR measurement of exposed individual tooth enamel are similar to measurement conditions of dose-effect calibration curve in this paper

  9. Visualization of Tooth for Non-Destructive Evaluation from CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hui; Chae, Ok Sam [Kyung Hee University, Seoul (Korea, Republic of)

    2009-06-15

    This paper reports an effort to develop 3D tooth visualization system from CT sequence images as a part of the non-destructive evaluation suitable for the simulation of endodontics, orthodontics and other dental treatments. We focus on the segmentation and visualization for the individual tooth. In dental CT images teeth are touching the adjacent teeth or surrounded by the alveolar bones with similar intensity. We propose an improved level set method with shape prior to separate a tooth from other teeth as well as the alveolar bones. Reconstructed 3D model of individual tooth based on the segmentation results indicates that our technique is a very conducive tool for tooth visualization, evaluation and diagnosis. Some comparative visualization results validate the non-destructive function of our method.

  10. The extractant

    International Nuclear Information System (INIS)

    The extractant for extraction and re-extraction of heavy metal ions has been worked out. The extractant consists of ferromagnetic particles suspended in liquid and covered by unsaturated fatty acids. The liquid, unsoluble in other liquids taken part in the process, contains also an organic derivative of phosphoric acid as a complexing agent

  11. Craniomandibular Trauma and Tooth Loss in Northern Dogs and Wolves: Implications for the Archaeological Study of Dog Husbandry and Domestication

    OpenAIRE

    Losey, Robert J; Jessup, Erin; Nomokonova, Tatiana; Sablin, Mikhail

    2014-01-01

    Archaeological dog remains from many areas clearly show that these animals suffered tooth fractures, tooth loss, trauma, and dental defects during their lives. Relatively little research has explored the meanings of these patterns, particularly for ancient dog remains from small-scale societies of the North. One limiting issue is the lack of comparative data on dental health and experiences of trauma among northern wolves and dogs. This paper examines tooth loss, tooth fracture, enamel hypopl...

  12. Diabetes and Tooth Loss in a National Sample of Dentate Adults Reporting Annual Dental Visits

    Directory of Open Access Journals (Sweden)

    Julie M. Kapp, PhD, MPH

    2007-07-01

    Full Text Available IntroductionPeriodontal disease has been associated with tooth loss and reported as more prevalent among people with diabetes than among those without diabetes. Having an annual dental examination is a national goal of Healthy People 2010. Our objective was to examine whether an association exists between diabetes and tooth loss among a population reporting an annual dental visit.MethodsWe used data from the 2004 Behavioral Risk Factor Surveillance System to examine the association between self-reported diabetes and tooth removal due to decay or periodontal disease among 155,280 respondents reporting a dental visit within the past year. We calculated prevalence estimates, odds ratios, and 95% confidence intervals. Multiple logistic regression allowed for adjustment.ResultsThe overall prevalence of tooth removal among the people in the study was 38.3%. People with diabetes had a significantly higher prevalence of tooth removal. In a multivariable model adjusting for selected covariates, respondents with diabetes were 1.46 times as likely (95% CI, 1.30–1.64 to have at least one tooth removed than respondents without diabetes. A stronger association between diabetes and tooth loss was observed among people in the younger age groups than among those in the older age groups.ConclusionEven among people reporting a recent dental visit, diabetes was independently associated with tooth loss. Multidisciplinary efforts are needed to raise awareness of the risk of tooth loss among younger people with diabetes. Good oral hygiene as well as annual dental examinations are important for preventing tooth loss.

  13. Comparison between observed children's tooth brushing habits and those reported by mothers

    Directory of Open Access Journals (Sweden)

    Pordeus Isabela A

    2011-09-01

    Full Text Available Abstract Background Information bias can occur in epidemiological studies and compromise scientific outcomes, especially when evaluating information given by a patient regarding their own health. The oral habits of children reported by their mothers are commonly used to evaluate tooth brushing practices and to estimate fluoride intake by children. The aim of the present study was to compare observed tooth-brushing habits of young children using fluoridated toothpaste with those reported by mothers. Methods A sample of 201 mothers and their children (aged 24-48 months from Montes Claros, Brazil, took part in a cross-sectional study. At day-care centres, the mothers answered a self-administered questionnaire on their child's tooth-brushing habits. The structured questionnaire had six items with two to three possible answers. An appointment was then made with each mother/child pair at day-care centres. The participants were asked to demonstrate the tooth-brushing practice as usually performed at home. A trained examiner observed and documented the procedure. Observed tooth brushing and that reported by mothers were compared for overall agreement using Cohen's Kappa coefficient and the McNemar test. Results Cohen's Kappa values comparing mothers' reports and tooth brushing observed by the examiner ranged from poor-to-good (0.00-0.75. There were statistically significant differences between observed tooth brushing habits and those reported by mothers (p Conclusions In general, there was low agreement between observed tooth brushing and mothers' reports. Moreover, the different methods of estimation resulted in differences in the frequencies of tooth brushing habits, indicative of reporting bias. Data regarding children's tooth-brushing habits as reported by mothers should be considered with caution in epidemiological surveys on fluoridated dentifrice use and the risk of dental fluorosis.

  14. Comparison of Intact dental pulp tissue characteristics, Comparison between primary and permanent tooth in dog

    Directory of Open Access Journals (Sweden)

    SE Jabbarifar

    2007-01-01

    Full Text Available Introduction: Responses of dental pulp in primary and permanent tooth are different to pulp therapy, trauma, caries, dehydration, pulp tester and dental materials. The reactions of primary dental pulp in compare with permanent dental pulp are different.Can these various reactions be attributed to different histological characteristics in two groups of teeth? The aim of this study is comparison of histological characteristics between dental pulps in two groups of teeth of dog.Methods and Materials: 20 primary and 20 permanent teeth of two dogs were selected. Forty teeth were extracted under general anesthesia. 1-2 millimeter of apices of roots were cut and immersed in 10% formaldehyde solution. Then the samples were sent to oral histological lab for staining and sliding. Oral pathologist examined the histology of dental pulps and reported the results. The data of study were analyzed by SPSS software 11.5. Then data were compared with Mann-Whitney and t-test. Finally findings were reported.Results: The relative frequency of fibroblasts, mesenchymal undifferentiating cells, blood vessels, collagen and nerve fibers and immune cells in primary and permanent dental pulp in dog had no significant difference (p value

  15. Effect of fluorides from various restorative materials on remineralization of adjacent tooth: An in vitro study

    Directory of Open Access Journals (Sweden)

    Baliga M

    2010-06-01

    Full Text Available The aim of the study was to evaluate the extent of surface zone remineralization and the effect of fluoride at the inter-proximal adjacent tooth surface, using restorative materials FusionAlloy, Ketac-Fil and Heliomolar. Ninety extracted molar teeth were used of which 45 were placed in artificial caries for 10 weeks. The remaining 45 teeth were filled with the respective restorative materials, mounted with the artificial carious teeth in proximal contact with plaster and placed in artificial saliva for a period of 28 days. Finally, sectioning of artificially carious teeth was done mesio-distally and observed under the optical microscope and scanning electron microscope. Comparison among the groups was done by one-way analysis of variance [ANOVA] and Fischer?s F test. Intercomparison between the groups was done by using Dunnett?s t-test. Results obtained from transmitted electron microscopic and scanning electron microscopic observations were almost similar with the Ketac-Fil and Heliomolar showing better results in surface zone remineralization compared to FusionAlloy. Also, Ketac-Fil is a good material in releasing fluoride to remineralize enamel when compared to Heliomolar and FusionAlloy. Thus, it can be used mainly in class II cavity restorations of primary and permanent dentitions due to the potential ability of fluoride containing glass ionomer cements and composite resins to remineralize incipient carious lesions on adjacent teeth.

  16. Tooth enamel electron spin resonance dosimetry of people living in the area with lime tobacco custom

    International Nuclear Information System (INIS)

    Objective: To study the effect of the custom of long term chewing lime tobacco on human tooth enamel electron spin resonance (ESR) dosimetry. Methods: A total of 20 enamel samples from lingual parts of adults teeth collected in Bombay, India were obtained by mechanical method. Some enamel samples from Japanese adults were extracted and 10 mixed samples were prepared. Enamel samples were exposed to different doses of 60Co ?-rays several times, and ESR spectra were measured after exposure. Results: ESR background signals of 9 Bombay samples were found 1.5-3.3 times higher than those of Japanese mixed samples. The ?-ray dose responses of dosimetric signal with higher background level were a little lower, and the average sensitivity was (0.42±0.03) mGy, which was close to that of Japanese mixed samples. Conclusions: The average level of background signals of Bombay samples was much higher than that of other non-chewing tobacco area, which was possibly caused by tobacco area, which was possibly caused by tobacco lime, the main component in chewing tobacco productions, and it would help to explore its special influences on ESR, and improve dose reconstruction in accuracy. (authors)

  17. Filling of extraction sockets of feline maxillary canine teeth with autogenous bone or bioactive glass

    Scientific Electronic Library Online (English)

    Adelina Maria da, Silva; Rafael Dias, Astolphi; Sílvia Helena Venturoli, Perri; Marion Burkhardt de, Koivisto.

    2013-12-01

    Full Text Available PURPOSE: To evaluate bone healing in the extraction socket of the feline maxillary canine tooth after grafting. METHODS: Eighteen adult cats were submitted to unilateral extraction of maxillary canine tooth and divided into three groups. In group 1 (n=6), control, the extraction socket was left empt [...] y. In group 2 (n=6), the extraction socket was filled with autogenous cancellous bone from the iliac crest and in group 3 (n=6), with bioactive glass particulate material. Cats were euthanized at four weeks postoperative. RESULTS: The radiographic examinations performed four weeks after surgery showed that in all groups the healing process converged to a radiopacity similar to that observed in the surrounding bones. Histological examination showed formation of woven bone within the extraction socket. The percentage of newly formed bone within the extraction socket, measured by the histometry, showed no statistically significant difference among the values of the three groups (Kruskal-Wallis'test p>0.05) (group 1: 63.96 ± 5.85, group 2: 66.84 ± 11.67, group 3: 59.28 ± 15.50). CONCLUSION: The bone regeneration observed in the extraction sockets filled with autogenous cancellous bone or bioactive glass was similar to that observed in the control sites, given an observation period of four weeks after extraction of the maxillary canine tooth.

  18. Experimental Model for Retrospective Assessment of X-Ray Exposures in Dento-Maxillary Radiology Measured by Electron Paramagnetic Resonance in Tooth Enamel

    OpenAIRE

    Ioana Costina DÂN?OREANU; Floarea FILDAN

    2009-01-01

    Electron paramagnetic resonance (EPR) dosimetry of human tooth enamel has been widely used in measuring radiation doses in various scenarios. For experimental purposes in X-ray diagnostic or therapy human persons can not be involved. For such cases we have developed an EPR dosimetry technique making use of enamel of molars extracted from pigs. The method can evaluate doses and dose-profiles of irradiated teeth at low level as 50 – 100 mGy (in air). EPR-spectra acquisition, data processing and...

  19. Scanning Electron Microscope (SEM) Evaluation of Tooth Surface Irradiated by Different Parameters of Erbium: Yttrium Aluminium Garnet (Er:YAG) Laser

    OpenAIRE

    Abbas Monzavi; Sima Shahabi; Nasim Chiniforush; Hanieh Nokhbatolfoghahaie

    2012-01-01

    INTRODUCTION: The aim of this study was to investigate the Scanning Electron Microscope (SEM) analysis of tooth surface irradiated by different parameters of Er:YAG laser.METHODS: 15 caries-free extracted human third molars were used in this study. The teeth were put into 5 groups for laser irradiation as follows: Group 1 (power: 2.5 W, Energy: 250 mJ); Group 2(power: 3 W, Energy: 300 mJ); Group 3 (power: 3.5 W, Energy: 350 mJ); Group 4 (power: 4 W, Energy: 400 mJ); Group 5 (power: 4.5 W, Ene...

  20. Experimental Model for Retrospective Assessment of X-Ray Exposures in Dento-Maxillary Radiology Measured by Electron Paramagnetic Resonance in Tooth Enamel

    Directory of Open Access Journals (Sweden)

    Ioana Costina DÂN?OREANU

    2009-12-01

    Full Text Available Electron paramagnetic resonance (EPR dosimetry of human tooth enamel has been widely used in measuring radiation doses in various scenarios. For experimental purposes in X-ray diagnostic or therapy human persons can not be involved. For such cases we have developed an EPR dosimetry technique making use of enamel of molars extracted from pigs. The method can evaluate doses and dose-profiles of irradiated teeth at low level as 50 – 100 mGy (in air. EPR-spectra acquisition, data processing and dose assessment were done using non-dedicated equipment, devices and software.

  1. Tooth wear in patients submitted to bariatric surgery

    Scientific Electronic Library Online (English)

    Maria do Socorro Coêlho, Alves; Fernando Alberto Costa Cardoso da, Silva; Stephanie Gomes, Araújo; Antônio Cláudio Almeida de, Carvalho; Alcione Miranda, Santos; Andrea Lúcia Almeida de, Carvalho.

    2012-04-01

    Full Text Available Cirurgia bariátrica pode provocar freqüentes episódios de vômito e refluxo gastroesofágico o que promove o contato dos ácidos gástricos com os dentes fazendo que haja perda irreversível de estrutura dental. Este estudo teve como objetivo avaliar a prevalência de desgaste dentário em pacientes bariát [...] ricos. Foram examinados 125 pacientes em um Hospital Público de São Luís, MA no período de julho a outubro de 2010, distribuídos em pacientes que já tinham sidos submetidos à cirurgia bariátrica há pelo menos 6 meses (Grupo bariátrico), obesos mórbidos que estavam na lista de espera para esta cirurgia (Grupo obeso) e por pacientes que esperavam por consulta médica ambulatorial em outros setores (Grupo controle). Os pacientes responderam a um questionário investigativo e foram examinados clinicamente utilizando o “Basic Erosive Wear Examination” - BEWE (Índice Básico do Desgaste Erosivo) que permite a classificação da severidade das lesões não-cariosas e avaliação de risco. Todos os pacientes apresentaram algum grau de desgaste dentário em diferentes níveis. No entanto, a presença de LDNC (lesão dental não-cariosa) estava associada ao grupo que o paciente pertencia. O grupo bariátrico apresentou maior prevalência e nível de risco em relação às LDNC’s estatisticamente significante quando comparado aos outros grupos, seguido pelo grupo de obeso e controle. Refluxo e vômito parecem não influenciar positivamente nas LDNC. Abstract in english Bariatric surgery may cause frequent vomiting episodes and gastroesophageal reflux, which promote the contact of gastric acids with the teeth leading to irreversible loss of tooth structure. The aim of this study was to assess prevalence of tooth wear in bariatric patients. One hundred and twenty-fi [...] ve patients were examined at a Public Hospital in São Luis, MA, Brazil, between July and October 2010, being patients who had already been submitted to the bariatric surgery at least 6 months previously (Bariatric group), morbidly obese patients who were on the waiting list for this surgery (Obese group) and patients who were waiting for ambulatory medical care in other sectors (Control group). The patients answered an investigative questionnaire and were clinically examined using the Basic Erosive Wear Examination (BEWE) scoring system, which allows the classification of the severity of noncarious dental lesions (NCDL) and evaluation of risk. All patients presented some degree of tooth wear at different levels. However, the presence of NCDL was associated with the group to which the patient belonged. The bariatric patients showed higher prevalence and a statistically significant level of risk with regard to NCDLs when compared with the other patients, followed by the obese and control groups. Reflux and vomiting did not seem to influence NCDL positively.

  2. Hand weakness in Charcot-Marie-Tooth disease 1X.

    LENUS (Irish Health Repository)

    Arthur-Farraj, P J

    2012-07-01

    There have been suggestions from previous studies that patients with Charcot-Marie-Tooth disease (CMT) have weaker dominant hand muscles. Since all studies to date have included a heterogeneous group of CMT patients we decided to analyse hand strength in 43 patients with CMT1X. We recorded handedness and the MRC scores for the first dorsal interosseous and abductor pollicis brevis muscles, median and ulnar nerve compound motor action potentials and conduction velocities in dominant and non-dominant hands. Twenty-two CMT1X patients (51%) had a weaker dominant hand; none had a stronger dominant hand. Mean MRC scores were significantly higher for first dorsal interosseous and abductor pollicis brevis in non-dominant hands compared to dominant hands. Median nerve compound motor action potentials were significantly reduced in dominant compared to non-dominant hands. We conclude that the dominant hand is weaker than the non-dominant hand in patients with CMT1X.

  3. Development of a Piezoelectric Ultrasonic Tooth-whitening Apparatus

    Directory of Open Access Journals (Sweden)

    Young-Jin Lee

    2013-10-01

    Full Text Available The aim of this study was to develop an ultrasonic tooth-whitening apparatus using piezoelectric transducers,which enhance bleaching efficiency by applying ultrasound, while performing a teeth whitening procedure. For thispurpose, an ultrasonic transducer was designed and manufactured, and the effects of reduction in the whiteningmaterial’s concentration and in the whitening treatment time through using the ultrasound cavitation phenomenonwere confirmed. Also, the validity of this study was investigated by comparing the whitening performance with acommercialized optical whitener, through color comparison. The results revealed that the ultrasound whitenerproduced color values that were enhanced by as much as double that of the conventional LED light whiteningmethod. Even when the operational time was reduced by half, the ultrasound method showed superior performanceby over 54% compared to the conventional light whitener, revealing that the ultrasound method showed a remarkabletreatment reduction effect.

  4. Control of erosive tooth wear: possibilities and rationale

    Directory of Open Access Journals (Sweden)

    Mônica Campos Serra

    2009-06-01

    Full Text Available Dental erosion is a type of wear caused by non bacterial acids or chelation. There is evidence of a significant increase in the prevalence of dental wear in the deciduous and permanent teeth as a consequence of the frequent intake of acidic foods and drinks, or due to gastric acid which may reach the oral cavity following reflux or vomiting episodes. The presence of acids is a prerequisite for dental erosion, but the erosive wear is complex and depends on the interaction of biological, chemical and behavioral factors. Even though erosion may be defined or described as an isolated process, in clinical situations other wear phenomena are expected to occur concomitantly, such as abrasive wear (which occurs, e.g, due to tooth brushing or mastication. In order to control dental loss due to erosive wear it is crucial to take into account its multifactorial nature, which predisposes some individuals to the condition.

  5. Control of erosive tooth wear: possibilities and rationale

    Scientific Electronic Library Online (English)

    Mônica Campos, Serra; Danielle Cristine Furtado, Messias; Cecilia Pedroso, Turssi.

    2009-06-01

    Full Text Available Dental erosion is a type of wear caused by non bacterial acids or chelation. There is evidence of a significant increase in the prevalence of dental wear in the deciduous and permanent teeth as a consequence of the frequent intake of acidic foods and drinks, or due to gastric acid which may reach th [...] e oral cavity following reflux or vomiting episodes. The presence of acids is a prerequisite for dental erosion, but the erosive wear is complex and depends on the interaction of biological, chemical and behavioral factors. Even though erosion may be defined or described as an isolated process, in clinical situations other wear phenomena are expected to occur concomitantly, such as abrasive wear (which occurs, e.g, due to tooth brushing or mastication). In order to control dental loss due to erosive wear it is crucial to take into account its multifactorial nature, which predisposes some individuals to the condition.

  6. Radicular cyst of primary tooth associated with maxillary sinus

    Science.gov (United States)

    Bahadure, Rakesh N; Khubchandani, Monika; Thosar, Nilima R; Singh, Rajeev Kumar

    2013-01-01

    Radicular cyst is one of the most common odontogenic cystic lesions found in the jaws. It is inflammatory in nature and found mostly in relation to a non-vital tooth. It usually presents at a later stage in life because the formation of the cyst is the last step in the progression of inflammatory events after a periapical infection. The cyst usually goes unnoticed because of its painless nature and small size. We present the clinical, radiographic and histological characteristics of a radicular cyst along with its management. Cystic sac was removed surgically under general anaesthesia after the elevation of the mucoperiosteal flap. Histopathologically, the cystic sac was consistent with the features of a radicular cyst. Follow-up period of 21?months showed improved radiographical appearance on Coned Beam CT. Vestibular deepening was planned as a future treatment in the same region. PMID:23833085

  7. Solitary osteochondroma of the trapezoid disguised as a tooth fragment.

    Science.gov (United States)

    Baumann, Andreas; Pereira, Daniela; Baldwin, Katy; Weusten, Axel

    2015-01-01

    Fight bite injuries of the hand are common presentations in A&E departments and usually result from a fist blow to the mouth. The authors report a case of a 24-year-old man who presented 6 weeks after an injury to his right wrist following an altercation. Radiographic examination and CT scans were in keeping with a tooth fragment embedded in the trapezoid. However, post excision histology subsequently revealed the lesion to be a solitary osteochondroma of the trapezoid. Osteochondromas are benign lesions of bony or cartilaginous origin and are usually found in the metaphyseal region of long bones. They represent by far the most common primary bone tumours. However, osteochondromas arising from the carpal bones are extremely rare with very few cases reported in the literature. This case illustrates the need to include 'tumour' as a differential diagnosis in every unusual appearing bony lesion, even if there is a history of trauma. PMID:26240108

  8. An interdisciplinary approach to treat crown-root-fractured tooth.

    Science.gov (United States)

    Sun, Ying Chun; Li, Ying; Tong, Jian; Gao, Ping

    2013-07-01

    Restoration of a crown-root subgingival fractured tooth, especially at anterior aesthetic zones is still a great challenge for restorative dentists. Crown lengthening procedure alone has the disadvantage of high gingival curve of the final restoration, which was not discontinuous to adjacent teeth and thus compromise cosmetic outcomes. The objective of this report is to display a new interdisciplinary approach which combining endodontic root canal treatment, orthodontic extrusion, periodontal crown lengthening surgery and prosthodontic post-core-crown restoration procedures to restore a crown-root subgingival fractured maxillary central incisor and achieved a satisfied cosmetic result. Computer-based spectrophotometer was also used to accurately select colour without objective interference to achieve ideal cosmetic effects. PMID:24249958

  9. Tooth enamel EPR dosimetry: sources of errors and their correction

    International Nuclear Information System (INIS)

    Some of the most important sources of systematic errors in dose determination using tooth enamel EPR spectroscopy and ways of reducing those errors are discussed. Enamel from the outside of the front teeth should not be used for dose determination because of induction of paramagnetic centers by solar light. The accuracy of the method in the low dose range is limited by variation in the shape of the EPR signal of unirradiated enamel, which can be described by an initial intrinsic signal and which varies for different samples with standard deviation of 20-30 mGy. The energy dependence of enamel sensitivity should be taken into account in the form of a correction factor. The value of this factor is estimated at 1.1-1.3 for real radiation fields in radiation contaminated territories. Variation in enamel sensitivity for different samples is shown to be within limits of 10-15% of the average value

  10. Multiple microscopy modalities applied to a sea urchin tooth fragment.

    Science.gov (United States)

    Stock, S R; Ignatiev, K; Dahl, T; Barss, J; Fezzaa, K; Veis, A; Lee, W K; De Carlo, F

    2003-09-01

    Two synchrotron X-ray microscopy methods, phase-contrast microradiography (the propagation method) and absorption microCT (high-resolution computed tomography or microtomography), and laser-scanning confocal microscopy (visible wavelength) were used to study a fragment of the keel of a tooth of the sea urchin Lytechinus variegatus. Stripes observed in the phase-contrast images of the fragment were also seen in confocal micrographs. MicroCT showed that the stripes were due to two parallel planar arrays of low-absorption channels within the bulk of the keel. In the phase microradiographs, maximum contrast stripes appear when a channel image from one row coincides with a channel image from the second row; otherwise, contrast is minimal. Long channels do not appear to have been observed previously in keels of sea urchin teeth. PMID:12944629

  11. Altered states: Effects of diagenesis on fossil tooth chemistry

    Science.gov (United States)

    Kohn, Matthew J.; Schoeninger, Margaret J.; Barker, William W.

    1999-09-01

    Investigation of modern and fossil teeth from northern and central Kenya, using the ion microprobe, electron microprobe, and transmission electron microscope, confirms that fossil tooth chemistry is controlled not only by the diagenetic precipitation of secondary minerals but also by the chemical alteration of the biogenic apatite. Increases in the concentrations of Fe, Mn, Si, Al, Ba, and possibly Cu in fossil vs. modern teeth reflect mixtures of apatite and secondary minerals. These secondary minerals occur in concentrations ranging from ˜0.3% in enamel to ˜5% in dentine and include sub-?m, interstitial Fe-bearing manganite [(Fe 3+, Mn 3+)O(OH)], and smectite. The pervasive distribution and fine grain size of the secondary minerals indicate that mixed analyses of primary and secondary material are unavoidable in in situ methods, even in ion microprobe spots only 10 ?m in diameter, and that bulk chemical analyses are severely biased. Increases in other elements, including the rare earth elements, U, F, and possibly Sr apparently reflect additional alteration of apatite in both dentine and enamel. Extreme care will be required to separate secondary minerals from original biogenic apatite for paleobiological or paleoclimate studies, and nonetheless bulk analyses of purified apatite may be suspect. Although the PO 4 component of teeth seems resistant to chemical alteration, the OH component is extensively altered. This OH alteration implies that bulk analyses of fossil tooth enamel for oxygen isotope composition may be systematically biased by ±1‰, and seasonal records of oxygen isotope composition may be spuriously shifted, enhanced, or diminished.

  12. Mercury speciation and selenium in toothed-whale muscles.

    Science.gov (United States)

    Sakamoto, Mineshi; Itai, Takaaki; Yasutake, Akira; Iwasaki, Toshihide; Yasunaga, Genta; Fujise, Yoshihiro; Nakamura, Masaaki; Murata, Katsuyuki; Man Chan, Hing; Domingo, José L; Marumoto, Masumi

    2015-11-01

    Mercury accumulates at high levels in marine mammal tissues. However, its speciation is poorly understood. The main goal of this investigation was to establish the relationships among mercury species and selenium (Se) concentrations in toothed-whale muscles at different mercury levels. The concentrations of total mercury (T-Hg), methylmercury (MeHg), inorganic mercury (I-Hg) and Se were determined in the muscles of four toothed-whale species: bottlenose dolphins (n=31), Risso's dolphins (n=30), striped dolphins (n=29), and short-finned pilot whales (n=30). In each species, the MeHg concentration increased with increasing T-Hg concentration, tending to reach a plateau. In contrast, the proportion of MeHg in T-Hg decreased from 90-100% to 20-40%. The levels of T-Hg and Se showed strong positive correlations. Se/I-Hg molar ratios rapidly decreased with the increase of I-Hg and reached almost 1 in all species. These results suggested that the demethylated MeHg immediately formed Se/I-Hg equimolar complex of mercury selenide (HgSe) in their muscles. In addition, an X-ray absorption fine structure analysis (XAFS) of a bottlenose dolphin muscle confirmed that the dominant chemical form of the Se/I-Hg equimolar complex was HgSe. HgSe was mainly localized in cells near the endomysium using electron probe microanalysis (EPMA). These results suggested that the demethylated MeHg finally deposits within muscle cells of bottlenose dolphin as an inert HgSe. PMID:26436307

  13. Clinical, radiological and histological diagnoses of periapical periodontitis spreading to the adjacent tooth: A case of endodontic failure

    OpenAIRE

    Luigi Cianconi; Manuele Mancini

    2013-01-01

    Aims: This article describes the apical infection in endodontically treated tooth 4.5 that spread to adjacent tooth 4.4. Case Report: A 52-year-old woman was referred for the presence of radiolucency extending from tooth 4.5 and mental foramen. Spontaneous symptoms were present. Tooth 4.5 showed poor-quality endodontics. The vitality of tooth 4.4 was negative, even though no mechanical trauma had been reported, nor was caries present. Both teeth were sensitive to percussion. Endodontic re-tr...

  14. Finite element-based force/moment-driven simulation of orthodontic tooth movement.

    Science.gov (United States)

    Geiger, M

    2013-01-01

    The objectives of this study were to develop a numerically controlled experimental set-up to predict the movement caused by the force systems of orthodontic devices and to experimentally verify this system. The presented experimental set-up incorporated an artificial tooth fixed via a 3D force/moment sensor to a parallel kinematics robot. An algorithm determining the initial movement of the tooth in its elastic embedding controlled the set-up. The initial tooth movement was described by constant compliances. The constants were obtained prior to the experiment in a parameterised finite element (FE) study on the basis of a validated FE model of a human molar. The long-term tooth movement was assembled by adding up a multiple of incremental steps of initial tooth movements. A pure translational movement of the tooth of about 8 mm resulted for a moment to force ratio of - 8.85 mm, corresponding to the distance between the bracket and the centre of resistance. The correct behaviour of this linear elastic model in its symmetry plane allows for simulating single tooth movement induced by orthodontic devices. PMID:22292517

  15. Tooth germ invagination from cell-cell interaction: Working hypothesis on mechanical instability.

    Science.gov (United States)

    Takigawa-Imamura, Hisako; Morita, Ritsuko; Iwaki, Takafumi; Tsuji, Takashi; Yoshikawa, Kenichi

    2015-10-01

    In the early stage of tooth germ development, the bud of the dental epithelium is invaginated by the underlying mesenchyme, resulting in the formation of a cap-like folded shape. This bud-to-cap transition plays a critical role in determining the steric design of the tooth. The epithelial-mesenchymal interaction within a tooth germ is essential for mediating the bud-to-cap transition. Here, we present a theoretical model to describe the autonomous process of the morphological transition, in which we introduce mechanical interactions among cells. Based on our observations, we assumed that peripheral cells of the dental epithelium bound tightly to each other to form an elastic sheet, and mesenchymal cells that covered the tooth germ would restrict its growth. By considering the time-dependent growth of cells, we were able to numerically show that the epithelium within the tooth germ buckled spontaneously, which is reminiscent of the cap-stage form. The difference in growth rates between the peripheral and interior parts of the dental epithelium, together with the steric size of the tooth germ, were determining factors for the number of invaginations. Our theoretical results provide a new hypothesis to explain the histological features of the tooth germ. PMID:26188369

  16. Analysis of tooth decay data in Japan using asymmetric statistical models

    Directory of Open Access Journals (Sweden)

    Tomizawa S

    2012-11-01

    Full Text Available Kouji Yamamoto,1 Sadao Tomizawa21Department of Medical Innovation, Osaka University Hospital, Osaka, 2Department of Information Sciences, Faculty of Science and Technology, Tokyo University of Science, Noda City, Chiba, JapanBackground: The aim of the present paper was to develop two new asymmetry probability models to analyze data for tooth decay from 363 women and 349 men aged 18–39 years who visited a dental clinic in Sapporo City, Japan, from 2001 to 2005.Methods: We analyzed the probability relationship between grade of upper and lower tooth decay for men and women using the two new models, and tested goodness-of-fit for the models.Results: The probability that a woman's (man's grade of lower tooth decay is i (i = 1,2 and her (his grade of upper tooth decay is j(>i, (j = 2,3 is estimated to be at most 13.52 (10.23 times higher than the probability that the woman's (man's grade of upper tooth decay is i and grade of lower tooth decay is j.Conclusion: From the data on tooth decay, decay of the upper teeth is worse than of the lower teeth in women and men, and the tendency becomes stronger as the numbers of decayed upper and lower teeth increase.Keywords: distance-proportional symmetry, asymmetry, square contingency table, teeth

  17. Tooth replacement and putative odontogenic stem cell niches in pharyngeal dentition of medaka (Oryzias latipes).

    Science.gov (United States)

    Abduweli, Dawud; Baba, Otto; Tabata, Makoto J; Higuchi, Kazunori; Mitani, Hiroshi; Takano, Yoshiro

    2014-04-01

    The small-sized teleost fish medaka, Oryzias latipes, has as many as 1000 pharyngeal teeth undergoing continuous replacement. In this study, we sought to identify the tooth-forming units and determine its replacement cycles, and further localize odontogenic stem cell niches in the pharyngeal dentition of medaka to gain insights into the mechanisms whereby continuous tooth replacement is maintained. Three-dimensional reconstruction of pharyngeal epithelium and sequential fluorochrome labeling of pharyngeal bones and teeth indicated that the individual functional teeth and their successional teeth were organized in families, each comprising up to five generations of teeth and successional tooth germs, and that the replacement cycle of functional teeth was approximately 4 weeks. BrdU label/chase experiments confirmed the existence of clusters of label-retaining epithelial cells at the posterior end of each tooth family where the expression of pluripotency marker Sox2 was confirmed by in situ hybridization. Label-retaining cells were also identified in the mesoderm immediately adjacent to the posterior end of each tooth family. These data suggest the importance of existence of slow-cycling dental epithelial cells and Sox2 expressions at the posterior end of each tooth family to maintain continuous tooth formation and replacement in the pharyngeal dentition of medaka. PMID:24463193

  18. How to best smash a snail: the effect of tooth shape on crushing load.

    Science.gov (United States)

    Crofts, S B; Summers, A P

    2014-03-01

    Organisms that are durophagous, hard prey consumers, have a diversity of tooth forms. To determine why we see this variation, we tested whether some tooth forms break shells better than others. We measured the force needed with three series of aluminium tooth models, which varied in concavity and the morphology of a stress concentrating cusp, to break a shell. We created functionally identical copies of two intertidal snail shells: the thicker shelled Nucella ostrina and the more ornamented Nucella lamellosa using a three-dimensional printer. In this way, we reduced variation in material properties between test shells, allowing us to test only the interaction of the experimental teeth with the two shell morphologies. We found that for all tooth shapes, thicker shells are harder to break than the thinner shells and that increased ornamentation has no discernible effect. Our results show that for both shell morphologies, domed and flat teeth break shells better than cupped teeth, and teeth with tall or skinny cusps break shells best. While our results indicate that there is an ideal tooth form for shell breaking, we do not see this shape in nature. This suggests a probable trade-off between tooth function and the structural integrity of the tooth. PMID:24430124

  19. The timing of tooth eruption and root development of permanent canine and premolars in Korean children

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the timing and sequence of eruption of permanent canine and premolars, and to evaluate tooth calcification stage on emergence in Korean children. The sample was comprised of 1,266 children (male 720, female 546) aged from 7-13 years. Tooth eruption and calcification stages were determined through oral and panoramic radiographic examination, respectively. Probit analysis was used to calculate the timing of tooth eruption and tooth calcification stage from these cross-sectional data. In both males and females, eruption occurred around the time when one third of tooth root or more was formed. The sequence was as follows: first premolar, canine, and second premolar in maxilla, and canine, first premolar and second premolar in mandible. Tooth eruption occurred earlier in girls compared with boys, averaging 0.63 years. Eruption sequence is identical in males and females with a trend for females to erupt earlier than males. Tooth eruption becomes earlier over the past decades in Korean children.

  20. Relationship between free radical content in child tooth enamel and radiation dose

    International Nuclear Information System (INIS)

    Free radical contents of the tooth enamel in 25 children permanent tooth and 35 milk tooth samples were measured by electron spin resonance (ESR) technique, and the relationship between free radical content of the tooth enamel and radiation dose was also investigated. Of the 25 children tooth samples there are 13 male samples and 12 female samples respectively, 20 male samples and 15 female samples. In 35 milk tooth samples permanent and milk tooth samples were divided into 5 dose groups each, and irradiated with 60Co ? ray at dose rate of 0.48 Gy/min. Radiation doses of 5 groups were 0.30, 0.50, 1.00, 3.00 and 5.00 Gy, respectively. Results indicated that there was no significant difference in background ESR signal intensity between male and female samples for both children permanent teeth and milk teeth. And also no significant difference in background ESR signal intensity between children permanent teeth and milk teeth was observed. Free radical content of teeth enamel increased linearly with increasing of radiation dose. The results could be applied to dose estimation of exposed individual in the case of radiation accident. Two methods of ESR dosimetry were also discussed

  1. Evaluation of the force applied by the tongue and lip on the maxillary central incisor tooth

    Scientific Electronic Library Online (English)

    Amanda Freitas, Valentim; Renata Maria Moreira Moraes, Furlan; Tatiana Vargas de Castro, Perilo; Monalise Costa Batista, Berbert; Andréa Rodrigues, Motta; Estevam Barbosa de Las, Casas.

    2014-06-01

    Full Text Available PURPOSE: To describe the development and testing of a system that measures forces exerted by the tongue and upper lip on a tooth during rest and during swallowing. METHODS: Twenty-eight subjects, aged 19-31 years (mean: 23.2 years) were submitted to measurement of forces exerted by the upper l [...] ip and tongue on the maxillary right central incisor tooth. Flexiforce resistive sensors were fixed on the labial and lingual surfaces of the tooth. They were connected to an amplifier circuit and a data acquisition board for processing and transmitting information to a computer. RESULTS: At rest, the tongue force on the tooth was 0.00±0.00 N and the lip force on tooth was 0.02±0.02 N. The difference between them was significant. During swallowing, the values were 0.31±0.38 N and 0.15±0.14 N, for the tongue and lip, respectively. This difference was not significant. CONCLUSION: At rest, the lip exerts a larger force than the tongue on the maxillary right central incisor tooth. During swallowing, there was no difference between lip and tongue force on the tooth.

  2. Tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students

    Directory of Open Access Journals (Sweden)

    Clement C. Azodo

    2010-08-01

    Full Text Available Objective: To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. Methods: A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on demography, frequency, duration and technique of tooth brushing and tongue cleaning as well as information on consumption of snacks. Results: A total of 242 students responded. Dental technology students made up 52.5% of the respondents and dental therapist in training made up 47.5%. Majority (63.2% of the respondents considered the strength of tooth brush when purchasing a tooth brush and 78.9% use tooth brushes with medium strength. Seven-tenth (71.9% of the respondents brush their teeth twice daily and 52.1% brush for 3–5 minutes. About one-third (30.2% brush their teeth in front of a mirror. Chewing stick was used by 51.7% of respondents in addition to the use of tooth brush. Tongue cleaning was done by 94.2% with only 9.5% using a tongue cleaner. Only 20.2% reported regular snacks consumption. Nine-tenth (90.4% of respondents were previously involved in educating others, apart from their colleagues, on tooth brushing. Conclusion: This survey revealed that most of the dental therapy and technology students had satisfactory tooth-brushing behaviour. The zeal to educate others about proper tooth brushing revealed in this study suggests that the students may be helpful in oral health promotion.

  3. Surgical management with intentional replantation on a tooth with palato-radicular groove.

    Science.gov (United States)

    Forero-López, Jorge; Gamboa-Martínez, Luis; Pico-Porras, Laura; Niño-Barrera, Javier Laureano

    2015-05-01

    A palato-radicular groove (PRG) is a developmental anomaly primarily found in the maxillary lateral incisors. It is a potential communication path between the root canal and the periodontium that decreases the survival prognosis of the affected tooth, therefore compromising the stability of the dental structure in the oral cavity. The aim of this case report is to present an original technique where a PRG was treated by means of intracanal disinfection, PRG sealing with glass ionomer, replantation with intentional horizontal 180 degree rotation of the tooth, and an aesthetic veneer placed to provide adequate tooth morphology. The clinical and biological benefits of this novel technique are presented and discussed. PMID:25984480

  4. Deconvolution of complex EPR spectrum of tooth enamel into three components: native, dosimetric and mechanical

    Energy Technology Data Exchange (ETDEWEB)

    Kirillov, Vladimir [Laboratory for EPR Dosimetry and Cytology, Belarusian State Medical University, 23 Philimonova Street, 220114 Minsk (Belarus)], E-mail: kirillov@bsmu.by; Dubovsky, Sergey [Laboratory for EPR Dosimetry and Cytology, Belarusian State Medical University, 23 Philimonova Street, 220114 Minsk (Belarus)

    2009-02-15

    A software was developed on the base of non-linear simulation, which allowed the deconvolution of EPR spectra of tooth enamel into three components: native, radiation- and mechanically induced. The software was designed for the reconstruction of individual absorbed doses by EPR spectra of tooth enamel using the method of additive irradiation of samples. It has been demonstrated with the help of this program that the presence of mechanically induced paramagnetic centers in enamel samples led to an excessive individual absorbed dose reconstructed by EPR spectra of tooth enamel.

  5. Replantation of an avulsed tooth with an extended extra oral period

    Directory of Open Access Journals (Sweden)

    Girish Kubasad

    2012-01-01

    Full Text Available In this study, we have reported a case of the replantation of a maxillary incisor with an extended extraoral period following a traumatic avulsion. After storage in normal saline, the root surface of the avulsed tooth was conditioned with citric acid and treated with a triple antibiotic solution. The tooth socket was filled with Emdogain before replantation. A 12 month, 18 month and a 5 year follow-up clinical examination revealed the patient to be asymptomatic, and the tooth was functional. The recall radiograph showed no evidence of renewed periradicular breakdown and apical root resorption.

  6. Retrospective Dosimetry: Dose Analysis From Tooth Enamel Using Electron Spin Resonance (ESR)

    International Nuclear Information System (INIS)

    The radiation dose should be accurately measured in order to relate its effect to the cells. The assessment of dose usually performed using biological dosimetry techniques. However, the reduction of lymphocytes (white blood cells) after the time period results in inaccuracy of dose measurement. An alternative method used is the application of Electron Spin Resonance (ESR) using tooth enamel. In this study, tooth enamels were evaluated and used to measure the individual absorbed dose from the background. The basic tooth features that would affect dose measurement were discussed. The results show this technique is capable and effective for retrospective dose measurement and useful for the study of radiation effect to human. (author)

  7. Uneven distribution of enamel in the tooth crown of a Plains Zebra (Equus quagga)

    OpenAIRE

    Winkler, Daniela E.; Kaiser, Thomas M.

    2015-01-01

    Unworn teeth of herbivorous mammals are not immediately functional. They have to be partially worn to expose enamel ridges which can then act as shear-cutting blades to break the food down. We use the Plains Zebra (Equus quagga) as a hypsodont, herbivorous model organism to investigate how initial wear of the tooth crown is controlled by underlying structures. We find that the enamel proportion is smaller at the apical half of the tooth crown in all upper tooth positions and suggest that lowe...

  8. Analysis of EPR tooth enamel spectra exposed to combined radiation and mechanical effects

    International Nuclear Information System (INIS)

    In the EPR spectra of tooth enamel samples exposed to sequential radiation and mechanical effect, the intensity of the signal in the spectra of tooth enamel samples exposed to sequential mechanical and radiation effects exceeded the amplitude of a signal in enamel samples that were only exposed to radiation. The increased dosimetric signal can be explained by superposition of mechanically and radiation-induced signals. The contribution of the mechanically induced component to the individual dose load reconstructed by EPR-spectra of tooth enamel has been evaluated

  9. Dependencies of the radiation sensitivity of human tooth enamel in EPR dosimetry

    International Nuclear Information System (INIS)

    The EPR dose response of tooth enamel was determined for human molars collected in Egypt. The influence of age, gender and residence of the tooth donors as well as tooth position and sample preparation on EPR sensitivity and its variability over the enamel samples was investigated. The EPR sensitivity and its variability were found to depend only on the sample preparation procedure. The variability in EPR sensitivity of enamel from Egyptian teeth was maximally 10% and the mean sensitivity was in good agreement with that of German teeth

  10. Deconvolution of complex EPR spectrum of tooth enamel into three components: native, dosimetric and mechanical

    International Nuclear Information System (INIS)

    A software was developed on the base of non-linear simulation, which allowed the deconvolution of EPR spectra of tooth enamel into three components: native, radiation- and mechanically induced. The software was designed for the reconstruction of individual absorbed doses by EPR spectra of tooth enamel using the method of additive irradiation of samples. It has been demonstrated with the help of this program that the presence of mechanically induced paramagnetic centers in enamel samples led to an excessive individual absorbed dose reconstructed by EPR spectra of tooth enamel.

  11. Cephalometric evaluation of soft tissue changes after extraction of upper first premolars in class ?? div 1 patients

    OpenAIRE

    Amirabadi, Gholamreza-Eslami; Mirzaie, Marzieh; Kushki, Somayyeh-Mehrabi; Olyaee, Pooya

    2014-01-01

    Introduction: Tooth extraction to provide sufficient space, or camouflage of underlying skeletal problems is quite common in orthodontics. The present study evaluated soft tissue changes after upper first premolars extraction in class ?? div 1 patients. Material and Methods: 20 cases (15 females, 5 males), with a mean age of 17.8±2.9 years with class ?? div1 malocclusion and normal vertical height, who needed upper first premolars extraction were selected. Pre- and post-treatment lateral c...

  12. Comparative analysis of the effect of autoclaving and 10% formalin storage on extracted teeth: A microleakage evaluation

    OpenAIRE

    Attam Kanika; Talwar Sangeeta; Yadav Seema; Miglani Sanjay

    2009-01-01

    Aim: This study compares the effect of formalin and autoclaving the tooth samples by evaluating microleakage in-vitro . Materials and Methods: Forty-five extracted human permanent incisor teeth were taken and randomly divided into three groups (with different methods of storage and disinfection) with 15 teeth each: Group 1: Control-extracted teeth in this group were stored in normal saline, Group 2: the extracted teeth in this group were stored in 10 % formalin for two weeks and Gr...

  13. Extraction process

    International Nuclear Information System (INIS)

    A process is described for extracting at least two desired constituents from a mineral, using a liquid reagent which produces the constituents, or compounds thereof, in separable form and independently extracting those constituents, or compounds. The process is especially valuable for the extraction of phosphoric acid and metal values from acidulated phosphate rock, the slurry being contacted with selective extractants for phosphoric acid and metal (e.g. uranium) values. In an example, uranium values are oxidized to uranyl form and extracted using an ion exchange resin. (U.K.)

  14. Extraction '90

    International Nuclear Information System (INIS)

    Over the past few years there has been a change in liquid-liquid solvent extraction from a process used mainly for metal recovery to more diverse areas such as pharmaceutical drug production. The conference reported here was organised by the Scottish Branch of the IChemE in association with AEA Technology Dounreay. The papers presented address the recent advances in solvent extraction, both industrial and academic, carried out in both the nuclear and non-nuclear fields. The broad areas covered are: extraction fundamentals, extraction from dilute solutions, sorption, extraction of biological products, and processes and equipment. (author)

  15. Gender differences in tooth loss among Chilean adolescents: socio-economic and behavioral correlates

    DEFF Research Database (Denmark)

    López, Rodrigo; Baelum, Vibeke

    2006-01-01

    OBJECTIVE: To investigate gender differences in tooth loss among Chilean adolescents and its association with selected socio-economic indicators and oral-health-related behaviors. MATERIAL AND METHODS: Data on 9,163 Chilean adolescents obtained using multistage random cluster procedures. Clinical recordings included information on missing teeth and the participants provided information on socio-demographic factors and oral-related behaviors. Two eruption-time-adjusted logistic regression analyses were used to investigate the associations between gender, tooth loss and socio-economic position/oral-health-related behaviors. RESULTS: The association between gender and tooth loss remained after adjusting for age, eruption times in both the socio-economic position regression model and the oral-health-related behaviors model. Tooth loss followed social gradients for the variables paternal income and achieved parental education, with students reporting a paternal income

  16. THE EFFECTS OF PGE1 AND INDOMETHACIN ON ORTHODONTIC TOOTH MOVEMENT IN RAT

    Directory of Open Access Journals (Sweden)

    EA. Niaki

    1999-09-01

    Full Text Available  Prostaglandin £j (PGE-^ and indomethacin, a nonstroidal antiinflammatory drug, were separately administered during ortliodontic tooth movement in rats. At the beginning, an orthodontic appliance was placed and activated in male albinos rats. In tlie first examination, the experimental group received submucosal injections of PGE-y (10 mg/kg/day near the first maxillary riglit molars, and alcohol was injected to control group animals as a vehicle similarly. Jn the second examination, indomethacin (10 mg/kg/day and metiiyl cellulose subcutaneousfy injected to experimental and control groups respectively. Tooth movement was measured at 1,3,5,7,9 and 11 days. In PGE^ group, tooth movement increased significantly at the beginning of seven days as compared to the vehicle injected group and the number of osteoclast and Howship's lacunae were markedly increased. A significant iniiibition of tooth movement occurred beginning at seven days in the indomethacin group compared to the control group.

  17. Finite element analysis of tooth load distribution on P-110S conic threaded connections

    International Nuclear Information System (INIS)

    Based on elastic mechanics and by use of thick cylinder theory, this paper presents a finite element analysis model with interference fit and axial load on P-110S conic threaded connections and the tooth load distributions on contact threaded surfaces were investigated. A 2D finite element model with elastic-plastic axisymmetric contact threaded surfaces was established and the tooth load distributions on its thread teeth were analyzed under different interference fit and axial load. Results for the loads on every engaged tooth are obtained. These indicate that the load distribution on the engaged teeth is not uniform, with the maximum tooth load concentrated on the first three pairs or the farthest two pairs of engaged teeth from the pin end and the middle teeth only bear a very small load. Such results are identical to the practical situation and indicate that the finite element model proposed in this paper is reasonable.

  18. Relationship between microhardness and fluorine contents on tooth enamel determined by PIGE analysis

    International Nuclear Information System (INIS)

    The remineralization effect of fluoride has been measured by surface microhardness on tooth enamel. The purpose of this study was to investigate the relationship between microhardness and fluorine concentration on tooth enamel. Twelve sound bovine enamel specimens were prepared and immersed in 0.05% NaF solution for 1, 3, 6, 24 and 36 hours, respectively. The concentration of fluorine in specimens were measured by PIGE analysis and surface microhardness of each specimen was measured by surface microhardness tester. Fluorine concentration was increased by immersing time. There was no change in microhardness of each specimen by fluorine content. The results of this study suggest that there was no relationship between the fluorine concentration and surface microhardness in sound tooth enamel. PIGE analysis can be used effectively to assess the remineralization effect of fluorine content in tooth enamel. (author)

  19. Whole Genome Sequencing Reveals Novel Non-Synonymous Mutation in Ectodysplasin A (EDA) Associated with Non-Syndromic X-Linked Dominant Congenital Tooth Agenesis

    OpenAIRE

    Sarkar, Tanmoy; Bansal, Rajesh; Das, Parimal

    2014-01-01

    Congenital tooth agenesis in human is characterized by failure of tooth development during tooth organogenesis. 300 genes in mouse and 30 genes in human so far have been known to regulate tooth development. However, candidature of only 5 genes viz. PAX9, MSX1, AXIN2, WNT10A and EDA have been experimentally established for congenitally missing teeth like hypodontia and oligodontia. In this study an Indian family with multiple congenital tooth agenesis was identified. Pattern of inheritance was...

  20. Professional and patient-based evaluation of oral rehabilitation in patients with tooth agenesis

    DEFF Research Database (Denmark)

    Dueled, Erik; Gotfredsen, Klaus

    2009-01-01

    OBJECTIVES: The outcome of oral rehabilitation is usually monitored with clinical tests rather than by patient's perception of change. The aim of this study was to describe the objective measure and subjective perception of oral rehabilitation in patients with tooth agenesis. MATERIAL AND METHODS: The study included 129 patients with tooth agenesis rehabilitated with implant- or tooth-supported reconstructions, and a control group of 58 patients. Professional assessments included biological, technical and aesthetic variables. An aesthetic index score included mucosal discoloration, crown morphology, crown color match, occlusal harmony, and papilla level. The Oral Health Impact Profile (OHIP) questionnaire was used to evaluate the patient-based outcomes. Six OHIP questions were subtracted to evaluate the patient-based aesthetic outcomes. RESULTS: Severe root resorption was observed in 36% of the patients in whom orthodontic treatment had been performed. Twelve percent of patients had implants with 5-7 mm peri-implant bone defects. Mucosal discoloration was recorded in 57% of the patients. Twelve percent of the patients had metal visible on the buccal side. The median scores for all five aesthetic variables were acceptable in 92% of the implant reconstructions and for 83% of the tooth-supported fixed dental prostheses (FDPs). The total OHIP score was inferior in rehabilitated patients with tooth agenesis to that of the control group without tooth agenesis. The total OHIP score after rehabilitation was <50 for 95% of the patients with tooth agenesis. The six OHIP questions concerning aesthetics demonstrated patient-based aesthetic problems in 41% of patients treated with implant-supported reconstructions and 47% of patients treated with tooth-supported FDPs. Ninety-eight percent of the group treated with implant-supported reconstructions and 84% of the patients in the tooth-supported FDP group were very satisfied or satisfied with the treatment outcome. CONCLUSIONS: Patients with tooth agenesis had a high risk ofsevere root resorption after orthodontic treatment. A better aesthetic outcome was obtained with implant-supported reconstructions than with tooth-supported reconstructions. A positive but not significant correlation was observed between the professional and patient-based evaluations of aesthetic outcomes.

  1. Cigarette smoking and tooth loss experience among young adults: a national record linkage study

    Directory of Open Access Journals (Sweden)

    Tanaka Keiko

    2007-11-01

    Full Text Available Abstract Background Various factors affect tooth loss in older age including cigarette smoking; however, evidence regarding the association between smoking and tooth loss during young adulthood is limited. The present study examined the association between cigarette smoking and tooth loss experience among adults aged 20–39 years using linked data from two national databases in Japan. Methods Two databases of the National Nutrition Survey (NNS and the Survey of Dental Diseases (SDD, which were conducted in 1999, were obtained from the Ministry of Health, Labor and Welfare with permission for analytical use. In the NNS, participants received physical examinations and were interviewed regarding dietary intake and health practices including cigarette smoking, whereas in the SDD, participants were asked about their frequency of daily brushing, and received oral examinations by certified dentists. Among 6,805 records electronically linked via household identification code, 1314 records of individuals aged 20 to 39 years were analyzed. The prevalence of 1+ tooth loss was compared among non-, former, and current smokers. Multiple logistic regression models were constructed including confounders: frequency of tooth brushing, body mass index, alcohol consumption, and intake of vitamins C and E. Results Smoking rates differed greatly in men (53.3% and women (15.5%. The overall prevalence of tooth loss was 31.4% (31.8% men and 31.1% women. Tooth loss occurred more frequently among current smokers (40.6% than former (23.1% and non-smokers (27.9%. Current smoking showed a significant association with 1+ tooth loss in men (adjusted OR = 2.21 [1.40–3.50], P = 0.0007 and women (1.70 [1.13–2.55], P = 0.0111. A significant positive exposure-related relationship between cigarette smoking status and tooth loss was observed (P for trend Conclusion An association between cigarette smoking and tooth loss was evident among young adults throughout Japan. Due to limitations of the available variables in the present databases, further studies including caries experience and its confounders should be conducted to examine whether smoking is a true risk of premature tooth loss in young adults.

  2. Severe tooth wear in Prader-Willi syndrome. A case–control study

    Directory of Open Access Journals (Sweden)

    Saeves Ronnaug

    2012-05-01

    Full Text Available Abstract Background Prader-Willi syndrome (PWS is a rare complex multsystemic genetic disorder characterized by severe neonatal hypotonia, endocrine disturbances, hyperphagia and obesity, mild mental retardation, learning disabilities, facial dysmorphology and oral abnormalities. The purpose of the present study was to explore the prevalence of tooth wear and possible risk factors in individuals with Prader-Willi syndrome. Methods Forty-nine individuals (6-40?years with PWS and an age- and sex-matched control group were included. Tooth wear was evaluated from dental casts and intraoral photographs and rated by four examiners using the Visual Erosion Dental Examination (VEDE scoring system and the individual tooth wear index IA. In accordance with the VEDE scoring system, tooth wear was also evaluated clinically. Whole saliva was collected. Results Mean VEDE score was 1.70?±?1.44 in the PWS group and 0.46?±?0.36 in the control group (p?A was 7.50 (2.60-30.70 in the PWS group and 2.60 (0.90-4.70 among controls (p?A; r?=?0.82, p?A; r?=?0.43, p?=?0.002. Tooth grinding was also associated with tooth wear in the PWS group, as indicated by the mean VEDE 2.67?±?1.62 in grinders and 1.14?±?0.97 in non-grinders (p?=?0.001 and median IA values 25.70 (5.48-68.55 in grinders and 5.70 (1.60-9.10 in non-grinders (p?=?0.003. Multivariate linear regression analysis was performed with tooth wear as the dependent variable and PWS (yes/no, age, tooth grinding and saliva secretion as independent variables. PWS (yes/no, age and tooth grinding retained a significant association with tooth wear, VEDE (p?A (p? Conclusions Our study provides evidence that tooth wear, in terms of both erosion and attrition, is a severe problem in Prader-Willi syndrome. There is therefore considerable need for prosthodontic rehabilitation in young adults with PWS.

  3. New therapeutic modalities to modulate orthodontic tooth movement

    Scientific Electronic Library Online (English)

    Ildeu, Andrade Jr; Ana Beatriz dos Santos, Sousa; Gabriela Gonçalves da, Silva.

    2014-12-01

    Full Text Available A modulação do movimento dentário ortodôntico (MDO) é desejável para os pacientes, pois reduz o tempo de tratamento, e também para ortodontistas, uma vez que a duração do tratamento tem sido associada a um aumento do risco de inflamação gengival, descalcificação, cárie dentária e reabsorção radicula [...] r. O crescente foco sobre os mecanismos biológicos da movimentação dentária levou a Ortodontia a ser uma especialidade mais abrangente, que hoje incorpora aspectos de todas as áreas da Medicina. Com o conhecimento atual, o uso de novas modalidades terapêuticas que visam a modulação da MDO, como a corticotomia, terapia a laser de baixa intensidade e vibração (ultrassom pulsátil de baixa intensidade) já são uma realidade clínica. Outras, como injeções locais de biomoduladores e a terapia genética, serão utilizadas em breve. Elas destinam-se a aumentar ou inibir o recrutamento, à diferenciação e/ou ativação das células ósseas, a acelerar ou reduzir a MDO, a aumentar a estabilidade dos resultados ortodônticos, bem como auxiliar na prevenção da reabsorção radicular. Esse artigo resume os estudos mais recentes sobre cada uma dessas novas modalidades terapêuticas, fornecendo informações aos leitores a respeito de como afetam a MDO e aponta futuras perspectivas clínicas. Abstract in english Modulation of orthodontic tooth movement (OTM) is desirable not only to patients because it shortens treatment time, but also to orthodontists, since treatment duration is associated with increased risk of gingival inflammation, decalcification, dental caries, and root resorption. The increased focu [...] s on the biological basis of tooth movement has rendered Orthodontics a more comprehensive specialty that incorporates facets of all fields of medicine. Current knowledge raises the possibility of using new therapeutic modalities for modulation of OTM, such as corticotomy, laser therapy, vibration (low-intensity pulsed ultrasound), local injections of biomodulators and gene therapy; with the latter being applicable in the near future. They are intended to enhance or inhibit recruitment, differentiation and/or activation of bone cells, accelerate or reduce OTM, increase stability of orthodontic results, as well as assist with the prevention of root resorption. This article summarizes recent studies on each one of these therapeutic modalities, provides readers with information about how they affect OTM and points out future clinical perspectives.

  4. Comparison of Tooth Size Discrepancy in Cl II Malocclusion Patients with Normal Occlusions

    OpenAIRE

    Moradi M "; ZareNemati P.; Padisar P.; Shojaeefard B.; Naseh R.

    2012-01-01

    Statement of Problem: There must be a proper mesiodistal tooth size ratio (Bolton analysis) between maxillary and mandibular teeth for good occlusal interdigitation. Therefore the Bolton analysis should be considered during diagnosis, treatment planning and predication of ultimate results.Purpose: The purpose of this study was to appraise tooth size ratios in Cl II malocclusion group and compare them with normal individuals. Materials and Method: This study was carried out on 60 pre-treatment...

  5. INHIBITORY EFFECT OF BISPHOSPHONATE [PAMIDRONATE] ON ORTHODONTIC TOOTH MOVEMENT IN NEWZEALAND ALBINO RABBITS

    OpenAIRE

    Venkataramana V1 , Rajasigamani K2 *, Nirmal Madhavan3 , S.N.Reddy4 , Karthik5 , KurunjiKumaran N6

    2012-01-01

    In orthodontics attaining absolute anchorage is one of the greater tasks for successful outcome of the treatment. The purpose of this study was to investigate the inhibitory effect of locally administered bisphosphonate – pamidronate on orthodontic tooth movement (OTM) in Newzealand albino male rabbits which could support the ‘Pharmacological Anchorage System’ i.e. preventing unwanted tooth movement to accomplish orthodontic anchorage by local administration of certain drugs. The present expe...

  6. Tooth apatite as a bone substitute: an experimental study and clinical applications

    International Nuclear Information System (INIS)

    The purpose of this study is to evaluate the usefulness of calcined teeth powder as biological apatite. The animal experiment was performed in 36 rabbits aging 6 weeks and weighing 1.6 kg. In experimental group, tooth apatite powder was implanted to 10 mm bony defects in diameter made on the cranial bone of the rabbits. As control groups, synthetic porous hydroxyapatite and resorbable type calcium carbonate were implanted to the defects of same size. Each group was sacrificed in 1, 2, 4, 6, 8, 12 weeks after the surgery. Specimens were prepared for decalcified samples and observed by a light microscope. And we also performed quantitative analysis of new bone formation through image analysis using computer. In clinical applications, we used tooth apatite alone or mixed with decalcified freeze-dried bone for reconstruction of bony defects in 15 patients undergone enucleation of cyst or ameloblastoma. The obtained results were as follows; 1) The powder of the calcined teeth was called as 'tooth apatite' and it seemed to have biocompatibility in rabbits and human. 2) In group of tooth apatite, after 4 weeks of operation, new bone directly bonded to the particles was observed. And in 12 weeks of it, new bone occupied most of the bony defects. In 6 weeks, resorption of the tooth apatite particles was observed. Thus the tooth apatite was regarded as one of resorbable apatite. 3) The group of tooth apatite showed new bone formation similar to the group of porous hydroxyapatite, but they were inferior to the group of resorbable calcium carbonate. 4) In clinical application, tooth apatite had biocompatibility and new bone formation was observed without any complication except for 1 case. So we think it is a useful bone substitute with osteoconductivity

  7. Studies of the chronological course of wisdom tooth eruption in a Black African population

    OpenAIRE

    Olze, Andreas; Van Niekerk, Piet; Schulz, Ronald; Schmeling, Andreas

    2007-01-01

    The importance of forensic age estimation in living subjects has grown over the last few years. In dental age estimation, tooth eruption is a parameter of developmental morphology that can be analyzed by either clinical examination or by evaluation of dental X-rays. In the present study, we determined the stage of wisdom tooth eruption in 410 male and 106 female black South African subjects of known age (12–26 years) based on radiological evidence from 516 conventional orthopantomograms. Four...

  8. Evaluation of Algesimetric Parameters on the Basis of Tooth Pulp Stimulation in Humans

    OpenAIRE

    Rohdewald, P.; Keuth, V.

    1990-01-01

    Investigations concerning the validity and sensitivity of algesimetric parameters were performed on 23 healthy volunteers on the basis of electrical tooth pulp stimulation. Bipolar tooth pulp stimulation has been proved to be superior to monopolar stimulation in respect to the reproducibility of threshold of sensation. Verbal numerical scale (VNS) was found to discriminate better between stimulus intensities than visual analogue scale in terms of sensitivity and reproducibility. The long-term...

  9. Digital Radiography for Determination of Primary Tooth Length: In Vivo and Ex Vivo Studies

    OpenAIRE

    Basso, Maria D.; Jeremias, Fabiano; Cordeiro, Rita C. L.; Santos-Pinto, Lourdes

    2015-01-01

    Background. Methods for determining the root canal length of the primary tooth should yield accurate and reproducible results. In vitro studies show some limitations, which do not allow their findings to be directly transferred to a clinical situation. Aim. To compare the accuracy of radiographic tooth length obtained from in vivo digital radiograph with that obtained from ex vivo digital radiograph. Method. Direct digital radiographs of 20 upper primary incisors were performed in teeth (2/3 ...

  10. Pseudogenization of the tooth gene enamelysin (MMP20) in the common ancestor of extant baleen whales

    OpenAIRE

    Meredith, Robert W; Gatesy, John; Cheng, Joyce; Springer, Mark S.

    2010-01-01

    Whales in the suborder Mysticeti are filter feeders that use baleen to sift zooplankton and small fish from ocean waters. Adult mysticetes lack teeth, although tooth buds are present in foetal stages. Cladistic analyses suggest that functional teeth were lost in the common ancestor of crown-group Mysticeti. DNA sequences for the tooth-specific genes, ameloblastin (AMBN), enamelin (ENAM) and amelogenin (AMEL), have frameshift mutations and/or stop codons in this taxon, but none of these molecu...

  11. Type XVII Collagen is a Key Player in Tooth Enamel Formation

    OpenAIRE

    Asaka, Takuya; Akiyama, Masashi; Domon, Takanori; Nishie, Wataru; Natsuga, Ken; FUJITA, Yasuyuki; ABE, Riichiro; Kitagawa, Yoshimasa; SHIMIZU, Hiroshi

    2009-01-01

    Inherited tooth enamel hypoplasia occurs due to mutations in genes that encode major enamel components. Enamel hypoplasia also has been reported in junctional epidermolysis bullosa, caused by mutations in the genes that encode type XVII collagen (COL17), a component of the epithelial-mesenchymal junction. To elucidate the pathological mechanisms of the enamel hypoplasia that arise from the deficiency of epithelial-mesenchymal junction molecules, such as COL17, we investigated tooth formation ...

  12. The adsorption of peptides and purified salivary proteins onto tooth enamel. A study on pellicle formation

    OpenAIRE

    Juriaanse, Adriaan Cornelis,

    1980-01-01

    The most common diseases that occur in the oral cavity are dental decay (caries) and inflammation of the soft tissues surrounding the teeth (periodontal disease). Both caries and periodontal disease are caused by bacterial metabolites in the plaque, an organic layer on the tooth surface, which consists of bacteria in a matrix composed of proteins and polysaccharides. The bacteria in the plaque digest sugar to form organic acids wich cause the dissolution of the tooth enamel (caries). ... ...

  13. Comparison study of tooth enamel ESR spectra of cows, goats and humans

    OpenAIRE

    Jiao, Ling; Liu, Zhong-Chao; Ding, Yan-Qiu; Ruan, Shu-Zhou; Wu, Quan; Fan, Sai-Jun; Zhang, Wen-yi

    2014-01-01

    The ESR radiation dosimetric properties of tooth enamel samples from cows and goats were investigated and compared with those of human samples. Samples were prepared first mechanically, and then chemically. The study results showed that the native signals from cow and goat samples were weaker than those from human samples; the radiation sensitivities for cow and goat samples were very close to those of human tooth enamel samples. These results indicated that cow and goat teeth could be altern...

  14. Tooth Enamel, the Result of the Relationship between Matrix Proteins and Hydroxyapatite Crystals

    OpenAIRE

    Carmen Mihaela MIHU; Diana DUDEA; Carmen MELINCOVICI; Bianca BOC?A

    2008-01-01

    Enamel, a structure of epithelial origin, represents a protective tooth cover. The cells responsible for the formation of enamel, ameloblasts, are lost at the time of tooth eruption, so that enamel becomes an acellular structure that can no longer regenerate. In order to compensate for this particular phenomenon, enamel has acquired a complex structural organization and a high mineralization degree, in its mature state. This reflects the particular life cycle of ameloblasts and the unique phy...

  15. Expression analysis of candidate genes regulating successional tooth formation in the human embryo

    OpenAIRE

    Olley, Ryan; Xavier, Guilherme M.; Seppala, Maisa; Volponi, Ana A.; Geoghegan, Fin; Sharpe, Paul T.; Cobourne, Martyn T

    2014-01-01

    Human dental development is characterized by formation of primary teeth, which are subsequently replaced by the secondary dentition. The secondary dentition consists of incisors, canines, and premolars, which are derived from the successional dental lamina of the corresponding primary tooth germs; and molar teeth, which develop as a continuation of the dental lamina. Currently, very little is known about the molecular regulation of human successional tooth formation. Here, we have investigate...

  16. Expression patterns of genes critical for BMP signaling pathway in developing human primary tooth germs.

    Science.gov (United States)

    Dong, Xiuqing; Shen, Bin; Ruan, Ningsheng; Guan, Zhen; Zhang, Yanding; Chen, YiPing; Hu, Xuefeng

    2014-12-01

    The developing murine tooth has been used as an excellent model system to study the molecular mechanism of organ development and regeneration. While the expression patterns of numerous regulatory genes have been examined and their roles have begun to be revealed in the developing murine tooth, little is known about gene expression and function in human tooth development. In order to unveil the molecular mechanisms that regulate human tooth morphogenesis, we examined the expression patterns of the major BMP signaling pathway molecules in the developing human tooth germ at the cap and bell stages by in situ hybridization, immunohistochemistry, and real-time RT-PCR. Expression of BMP ligands and antagonist, including BMP2, BMP3, BMP4, BMP7, and NOOGGIN, exhibited uniform patterns in the tooth germs of incisor and molar at the cap and bell stages with stronger expression in the inner dental epithelium than that in the dental mesenchyme. Both type I and type II BMP receptors were present in widespread expression pattern in the whole-enamel organ and the dental mesenchyme with the strongest expression in inner dental epithelium at the cap and bell stages. SMAD4 and SMAD1/5/8 showed an expression pattern similar to that of BMP ligands with more intensive signals in the inner dental epithelium. Despite some unique and distinct patterns as compared to the mouse, the intensive expression of BMP signaling pathway molecules in the developing human tooth strongly suggests conserved functions of BMP signaling during human odontogenesis, such as in mediating tissue interactions and regulating differentiation and organization of odontogenic tissues. Our results provide an important set of documents for studying molecular regulatory mechanisms underlying tooth development and regeneration in humans. PMID:24993805

  17. Dose response of hydrazine - Deproteinated tooth enamel under blue light stimulation

    International Nuclear Information System (INIS)

    The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.

  18. Biological Dentin Post for Intra Radicular Rehabilitation of A Fractured Anterior Tooth

    OpenAIRE

    Swarupa, C.H; Sajjan, Girija S.; Bhupahupathiraju, Vijaya Lakshmi; Anwarullahwarullah, Anupreeta; Y.V, Sashikanth

    2014-01-01

    Ideal coronal reconstruction of endodontically treated tooth is still a challenge for restorative dentistry. Despite having varied types of commercially available posts, none of them meet all the ideal biological and mechanical properties. In this context a “Biological Post” serves as a homologous recipe for intraradicular rehabilitation of a fractured endodontically treated tooth by virtue of its biomimetic property.This case report addresses the esthetic and functional restoration of a frac...

  19. Acceleration of tooth movement during orthodontic treatment - a frontier in Orthodontics

    OpenAIRE

    Nimeri, Ghada; Kau, Chung H; Abou-Kheir, Nadia S; Corona, Rachel

    2013-01-01

    Nowadays, there is an increased tendency for researches to focus on accelerating methods for tooth movement due to the huge demand for adults for a shorter orthodontic treatment time. Unfortunately, long orthodontic treatment time poses several disadvantages like higher predisposition to caries, gingival recession, and root resorption. This increases the demand to find the best method to increase tooth movement with the least possible disadvantages. The purpose of this study is to view the su...

  20. Future dentistry: cell therapy meets tooth and periodontal repair and regeneration

    OpenAIRE

    Catón, Javier; Bostanci, Nagihan; Remboutsika, Eumorphia; De Bari, Cosimo; Mitsiadis, Thimios A

    2011-01-01

    Cell-based tissue repair of the tooth and – tooth-supporting – periodontal ligament (PDL) is a new attractive approach that complements traditional restorative or surgical techniques for replacement of injured or pathologically damaged tissues. In such therapeutic approaches, stem cells and/or progenitor cells are manipulated in vitro and administered to patients as living and dynamic biological agents. In this review, we discuss the clonogenic potential of human dental and periodontal tissue...

  1. Effect of repeated immersion solution cycles on the color stability of denture tooth acrylic resins

    Scientific Electronic Library Online (English)

    Paulo Maurício Batista da, Silva; Emílio José Tabaré Rodríguez, Acosta; Matheus, Jacobina; Luciana de Rezende, Pinto; Vinícius Carvalho, Porto.

    2011-12-01

    Full Text Available OBJECTIVE: Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected [...] the color stability of two denture tooth acrylic resins. MATERIAL AND METHODS: Sixty disc-shaped specimens (40 mm x 3 mm) were fabricated from two different brands (Artiplus and Trilux) of denture tooth acrylic resin. The specimens from each brand (n=30) were randomly divided into 6 groups (n=5) and immersed in the following solutions: distilled water (control group) and 5 disinfecting solutions (1% sodium hypochlorite, 2% sodium hypochlorite, 5.25% sodium hypochlorite, 2% glutaraldehyde, and 4% chlorhexidine gluconate). Tooth color measurements were made by spectrophotometry. Before disinfection, the initial color of each tooth was recorded. Further color measurements were determined after subjecting the specimens to 7, 21, 30, 45, 60, and 90 immersion cycles in each tested solution. Color differences (?E*) were determined using the CIE L*a*b* color system. Data were analyzed using two-way repeated measures analysis of variance (ANOVA) followed by Tukey tests. The significance level was set at 5%. RESULTS: There were statistically significant differences in ?E* among the 5 disinfectants and water during the 90 cycles of immersion for both denture tooth acrylic resins. Distilled water promoted the greatest color change in both denture tooth acrylic resins, nevertheless none of tested disinfectants promoted ?E* values higher than 1.0 on these acrylic materials during the 90 cycles of disinfection. CONCLUSIONS: Repeated immersion cycles in disinfecting solutions alter ?E* values, however these values do not compromise the color of the tested denture tooth acrylic resins because they are imperceptible to the human eye.

  2. Study of New Type Herringbone Gear with Narrow Tooth Width and Beveloid Teeth

    OpenAIRE

    Chao Lin; Zheng Guo; Bingkui Chen; Caichao Zhu

    2013-01-01

    New narrow herringbone gear, a new kind of transmission, is derived from traditional herringbone gear and broadens its application range. Based on the theories of differential geometry and gear meshing principles, the author describes the tooth and the transmission characteristics of the gear and deduces the equations of tooth face and fillet. According to the theories of material mechanics and gear strength check, the author deduces the equations of gear f...

  3. Dose response of hydrazine - Deproteinated tooth enamel under blue light stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Yuece, Ulkue Rabia, E-mail: ulkuyuce@hotmail.co [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Meric, Niyazi, E-mail: meric@ankara.edu.t [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Atakol, Orhan, E-mail: atakol@science.ankara.edu.t [Ankara University, Science Faculty, Department of Chemistry, 06100, Tandogan - Ankara (Turkey); Yasar, Fusun, E-mail: ab121310@adalet.gov.t [Council of Forensic Medicine, Ankara Branch, Ankara (Turkey)

    2010-08-15

    The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.

  4. Effect of repeated immersion solution cycles on the color stability of denture tooth acrylic resins

    OpenAIRE

    Paulo Maurício Batista da Silva; Emílio José Tabaré Rodríguez Acosta; Matheus Jacobina; Luciana Rezende Pinto; Vinícius Carvalho Porto

    2011-01-01

    OBJECTIVE: Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected the color stability of two denture tooth acrylic resins. MATERIAL AND METHODS: Sixty disc-shaped specimens (40 mm x 3 mm) were fabricated from two different brands (Artiplus and Trilux) of denture ...

  5. Effect of repeated immersion solution cycles on the color stability of denture tooth acrylic resins

    Directory of Open Access Journals (Sweden)

    Paulo Maurício Batista da Silva

    2011-12-01

    Full Text Available OBJECTIVE: Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected the color stability of two denture tooth acrylic resins. MATERIAL AND METHODS: Sixty disc-shaped specimens (40 mm x 3 mm were fabricated from two different brands (Artiplus and Trilux of denture tooth acrylic resin. The specimens from each brand (n=30 were randomly divided into 6 groups (n=5 and immersed in the following solutions: distilled water (control group and 5 disinfecting solutions (1% sodium hypochlorite, 2% sodium hypochlorite, 5.25% sodium hypochlorite, 2% glutaraldehyde, and 4% chlorhexidine gluconate. Tooth color measurements were made by spectrophotometry. Before disinfection, the initial color of each tooth was recorded. Further color measurements were determined after subjecting the specimens to 7, 21, 30, 45, 60, and 90 immersion cycles in each tested solution. Color differences (?E* were determined using the CIE L*a*b* color system. Data were analyzed using two-way repeated measures analysis of variance (ANOVA followed by Tukey tests. The significance level was set at 5%. RESULTS: There were statistically significant differences in ?E* among the 5 disinfectants and water during the 90 cycles of immersion for both denture tooth acrylic resins. Distilled water promoted the greatest color change in both denture tooth acrylic resins, nevertheless none of tested disinfectants promoted ?E* values higher than 1.0 on these acrylic materials during the 90 cycles of disinfection. CONCLUSIONS: Repeated immersion cycles in disinfecting solutions alter ?E* values, however these values do not compromise the color of the tested denture tooth acrylic resins because they are imperceptible to the human eye.

  6. Platelet-rich fibrin-mediated revitalization of immature necrotic tooth

    Directory of Open Access Journals (Sweden)

    Navin Mishra

    2013-01-01

    Full Text Available Contemporary studies have shown that the regeneration of tissues and root elongation is possible in necrotic immature permanent teeth. The purpose of this case report is to add a new vista in regenerative endodontic therapy by using platelet rich fibrin for revitalization of immature non vital tooth. An 11year old boy with the history of trauma was diagnosed with the pulpal necrosis and symptomatic apical periodontitis in tooth #21. Intra oral periapical radiograph showed open apex and associated immature supernumerary tooth with respect to tooth #21. Access preparation and minimal instrumentation was done to remove necrotic debris under copious irrigation with 2.5% sodium hypochlorite. Triple antibiotic paste was packed in the canal for four weeks. During second visit, 5 mL of whole blood was drawn from the medial cubital vein of the patient and blood was then subjected to centrifugation at 2400 rpm for 12 minutes for the preparation of Platelet rich fibrin (PRF utilizing Choukroun?s method. Triple antibiotic paste was removed and canal was dried. PRF clot was pushed to the apical region of tooth #21 using hand pluggers. Three milimetres of Mineral trioxide (MTA was placed in cervical part of the root canal and permanent restoration was done three days later. Clinical examination at 6 and 12 months revealed no sensitivity to percussion and palpation in tooth #21and it responded positively to both electric pulp and cold tests. Radiographic examination showed resolution of periapical rarefaction, further root development and apical closure of the tooth #21 and its associated supernumerary tooth. On the basis of successful outcome of the present case it can be stated that PRF clot may serve as a scaffold for regeneration of necrotic immature teeth.

  7. Platelet Rich Fibrin in the revitalization of tooth with necrotic pulp and open apex

    OpenAIRE

    Shivashankar, Vasundara Yayathi; Johns, Dexton Antony; S Vidyanath; Kumar, M Ramesh

    2012-01-01

    Regeneration of pulp-dentin complex in an infected necrotic tooth with an open apex is possible if the canal is effectively disinfected. The purpose of this case report is to add a regenerative endodontic case to the existing literature about using Platelet Rich Fibrin (PRF). A nine year old boy who accidently broke his immature maxillary central incisor tooth, developed pulpal necrosis with apical periodontitis. After the access cavity preparation, the canal was effectively irrigated with 20...

  8. Dentistry and molecular biology: a promising field for tooth agenesis management.

    Science.gov (United States)

    Boeira Junior, Breno Ramos; Echeverrigaray, Sergio

    2012-01-01

    Tooth agenesis is the failure of tooth bud development, causing definitive absence of the tooth. It is the most common dental anomaly, affecting up to one-quarter of the general population. The main cause is related to abnormal function of specific genes which play key roles during odontogenesis, particularly MSX1 and PAX9. MSX1 is a transcription factor highly expressed in the mesenchyme of developing tooth germs, whereas PAX9 is a transcription factor that shows a direct relationship with craniofacial development, particularly the formation of the palate and teeth. Despite the high frequency of tooth agenesis, there are as yet only a restricted number of mutations in MSX1 and PAX9 that have been associated with non-syndromic tooth agenesis. Thus, a deeper analysis of the gene networks underlying this anomaly is imperative. By means of a literature review based on Medline, PubMed, Lilacs, NCBI, and STRING, performed between 1991 and 2010 and focused on etiologically associated mutations, this work aimed to assess the latest advances in the genetic etiology of tooth agenesis and to offer an insight into how they can assist dental practice in the near future. A better knowledge of the genetic networks underlying tooth agenesis will lead to better treatment options and, perhaps, a tool for early diagnosis possibly related to DNA examination based on polymorphic variants. Such a test based on DNA analysis may be available to and accessible by clinicians, resulting in a more accurate diagnosis and allowing for a better approach to this anomaly. PMID:22452934

  9. A comparative examination of odontogenic gene expression in both toothed and toothless amniotes

    OpenAIRE

    Lainoff, Alexis J.; Moustakas-Verho, Jacqueline E.; Hu, Diane; Kallonen, Aki; Marcucio, Ralph S.; Hlusko, Leslea J.

    2015-01-01

    A well-known tenet of murine tooth development is that BMP4 and FGF8 antagonistically initiate odontogenesis, but whether this tenet is conserved across amniotes is largely unexplored. Moreover, changes in BMP4-signaling have previously been implicated in evolutionary tooth loss in Aves. Here we demonstrate that Bmp4, Msx1, and Msx2 expression is limited proximally in the red-eared slider turtle (Trachemys scripta) mandible at stages equivalent to those at which odontogenesis is initiated in ...

  10. Natural selection and molecular evolution in primate PAX9 gene, a major determinant of tooth development

    OpenAIRE

    Pereira, Tiago V; Francisco M Salzano; MOSTOWSKA, ADRIANNA; Trzeciak, Wieslaw H.; Ruiz-Linares, Andrés; José A.B Chies; Saavedra, Carmen; Nagamachi, Cleusa; Hurtado, Ana M.; Hill, Kim; Castro-de-Guerra, Dinorah; Silva-Júnior, Wilson A.; Bortolini, Maria-Cátira

    2006-01-01

    Large differences in relation to dental size, number, and morphology among and within modern human populations and between modern humans and other primate species have been observed. Molecular studies have demonstrated that tooth development is under strict genetic control, but, the genetic basis of primate tooth variation remains unknown. The PAX9 gene, which codes for a paired domain-containing transcription factor that plays an essential role in the development of mammal dentition, has bee...

  11. Tumour suppressor p53 in tooth development in the field vole (Microtus agrestis, Rodentia).

    Czech Academy of Sciences Publication Activity Database

    Matulová, Petra; Witter, K.; Šetková, Jana; Míšek, Ivan

    London : University of York, 2004. s. 90. [ COST ACTION B23 "Oral facial devlopment and regeneration", Management comittee /3./ in connection with International conference on tooth morphogenesis and differentiation /8./. 17.07.2004-22.07.2004, York] R&D Projects: GA ?R GA304/04/0101; GA MŠk OC B23.001 Keywords : tooth development Subject RIV: EB - Genetics ; Molecular Biology

  12. Analysis of stress state of toothed ring of flexspline by means the BEM

    OpenAIRE

    P. Fol?ga

    2013-01-01

    Purpose: The paper presents an analysis of the influence of design features of the flexspline in a harmonic drive, such as the relative radial deformation, the relative coating thickness and the design features of the basic rack tooth profile, on stress values in the bottom lands of a toothed ring.Design/methodology/approach: In numerical calculations, the software developed at the Faculty of Transport of the Silesian University of Technology was used. The program automatically generates a pr...

  13. Tooth in the line of fracture: Its prognosis and its effects on healing

    Directory of Open Access Journals (Sweden)

    Sachin Rai

    2011-01-01

    Conclusion: Postoperative occlusal discrepancy is less but infection is higher when the tooth in the line of fracture is preserved as compared to when it is removed. More than half of the teeth in the fracture line show complete recovery within a period of 6 months to 1 year. Despite the risk of an increase in the rate of complications, the tooth in the line of fracture should be preserved for its merits.

  14. Triclosan-loaded Tooth-binding Micelles for Prevention and Treatment of Dental Biofilm

    OpenAIRE

    Chen, Fu; Rice, Kelly C; Liu, Xin-ming; Reinhardt, Richard A.; Bayles, Kenneth W.; Wang, Dong

    2010-01-01

    The purpose of the present study was to develop tooth-binding micelle formulations and evaluate their ability to both inhibit initial biofilm formation as well as decrease the viability of preformed biofilm using an in vitro dental biofilm model. Alendronate (ALN, a bisphosphonate) was covalently attached to the ends of different Pluronic copolymers to confer tooth-binding ability to the micelles, and triclosan was used as a model drug. Based on different micelle preparation methods, Pluronic...

  15. The expression of nr0b1, the earliest gene in zebrafish tooth development, is a marker for human tooth and ameloblastoma formation

    OpenAIRE

    Powers, Jamie; Zhao, Yan; Lin, Shuo; McCabe, Edward R.B.

    2009-01-01

    Zebrafish teeth develop on pharyngeal jaws in the 5th branchial arch, but early tooth development is remarkably similar to mammals (Borday-Birraux et al., Evol Dev 8:130, 2006). Recently, eve1 has been shown to be associated with the primary tooth (4V1) and early ameloblast development, the enamel organ precursor (Laurenti et al., Dev Dyn 230:727, 2004). dax1 is initially expressed in the 5th branchial arch in zebrafish at approximately 26 h postfertilization (hpf) and colocalizes with eve1 e...

  16. [A study on tooth marks--morphological differences between dentitions and tooth marks thereof and selection of measurement items effective in identification].

    Science.gov (United States)

    Aboshi, H

    1989-04-01

    Tooth marks in human skin assume so various aspects depending upon such factors as the forms and properties of the bitten regions that they do not necessarily represent the dentition of a suspect as it is. In the present study a cylindrical dummy with skin-like elasticity was used as a recording medium on which to make experimental tooth marks. Morphological comparisons were made of the tooth marks with the oral models by the use of measurements of 28 items. Furthermore, the selection of the effective items for identification was also considered by applying the discriminant analysis to the rate of morphological change on the base of the measurements. The results obtained were as follows: 1) In respect of the tooth marks and the oral models derived from the same subject, the values of their difference (i.e., the measured value of the former minus that of the latter) were calculated for each item so that the directional changes of the tooth marks should be investigated. It was found that the values for the lengths of the dental arch showed a tendency to be positive and that those for the widths negative, and that the values for the angles of lateral incisors and canines tended to be positive. 2) Among the mean values of the rates of morphological change for each item on the same subject, those for the lengths of the dental arch were larger, whereas those for the widths were smaller. Regarding the widths of tooth edge, large were those values for the mandibular canines in particular. 3) The identifying indices were calculated from the rate of morphological change on the basis of the measured values for 28 items in 400 combinations of the oral models with the tooth marks. They indicated that, out of the combinations derived from different subjects, 11.3% for maxillary overlapped those from the same subject and so did 8.7% for mandible in the distribution of their indices. 4) A discriminant analysis was carried out for identification. The range of coefficients thereby obtained rendered it possible to consider how much each item contributed to identification. As a result, the range of the inter-canine distance was largest. It could be considered that these items are effective in identification for tooth marks by using measurements. PMID:2810892

  17. The EPR investigation of tooth enamel for measurements of tooth enamel for measurements of absorbed gamma doses of people irradiated in Chernobyl accident

    International Nuclear Information System (INIS)

    The EPR spectra of the tooth enamel of Chernobyl 'liquidators' were investigated. A lot of people were engaged in work at the Chernobyl area after the accident in 1986. A part of them is under regular medical control at the Ukrainian security service hospital. When patients lose the teeth for some reasons the EPR spectra of radiation centers in tooth enamel caused by emergency gamma radiation were investigated. The measurement of the intensities of the EPR spectra give the real individual absorbed doses of gamma radiation which are much higher than the official values registered in the medical cards of liquidators

  18. Differential expression of decorin and biglycan genes during mouse tooth development

    Science.gov (United States)

    Matsuura, T.; Duarte, W. R.; Cheng, H.; Uzawa, K.; Yamauchi, M.

    2001-01-01

    Small leucine-rich proteoglycans (SLRPs) have a number of biological functions and some of them are thought to regulate collagen mineralizaton in bone and tooth. We have previously identified and immunolocalized two members of the SLRPs family, decorin and biglycan, in bovine tooth/periodontium. To investigate their potential roles in tooth development, we examined the mRNA expression patterns of decorin, biglycan and type I collagen in newborn (day 19) mice tooth germs by in situ hybridization. At this developmental stage, the first maxillary and mandibular molars include stages before and after secretion of the predentin matrix, respectively. The expression of decorin mRNA coincided with that of type I collagen mRNA and was mostly observed in secretory odontoblasts, while the biglycan mRNA was expressed throughout the tooth germ, including pre-secretory odontoblasts/ameloblasts, dental papilla and stellate reticulum. However, its signal in secretory odontoblasts was not as evident as that of decorin. In mandibular incisors, where a significant amount of predentin matrix and a small amount of enamel matrix were already secreted, a similar differential expression pattern was observed. In secretory ameloblasts the biglycan mRNA expression was apparent, while that of decorin was not. These differential expression patterns suggest the distinct roles of biglycan and decorin in the process of tooth development.

  19. Use of quantitative light-induced fluorescence to monitor tooth whitening

    Science.gov (United States)

    Amaechi, Bennett T.; Higham, Susan M.

    2001-04-01

    The changing of tooth shade by whitening agents occurs gradually. Apart from being subjective and affected by the conditions of the surroundings, visual observation cannot detect a very slight change in tooth color. An electronic method, which can communicate the color change quantitatively, would be more reliable. Quantitative Light- induced Fluorescence (QLF) was developed to detect and assess dental caries based on the phenomenon of change of autofluorescence of a tooth by demineralization. However, stains on the tooth surface exhibit the same phenomenon, and therefore QLF can be used to measure the percentage fluorescence change of stained enamel with respect to surrounding unstained enamel. The present study described a technique of assessing the effect of a tooth-whitening agent using QLF. This was demonstrated in two experiments in which either wholly or partially stained teeth were whitened by intermittent immersion in sodium hypochlorite. Following each immersion, the integrated fluorescence change due to the stain was quantified using QLF. In either situation, the value of (Delta) Q decreased linearly as the tooth regained its natural shade. It was concluded that gradual changing of the shade of discolored teeth by a whitening agent could be quantified using QLF.

  20. The Biomechanical Function of Periodontal Ligament Fibres in Orthodontic Tooth Movement

    Science.gov (United States)

    McCormack, Steven W.; Witzel, Ulrich; Watson, Peter J.; Fagan, Michael J.; Gröning, Flora

    2014-01-01

    Orthodontic tooth movement occurs as a result of resorption and formation of the alveolar bone due to an applied load, but the stimulus responsible for triggering orthodontic tooth movement remains the subject of debate. It has been suggested that the periodontal ligament (PDL) plays a key role. However, the mechanical function of the PDL in orthodontic tooth movement is not well understood as most mechanical models of the PDL to date have ignored the fibrous structure of the PDL. In this study we use finite element (FE) analysis to investigate the strains in the alveolar bone due to occlusal and orthodontic loads when PDL is modelled as a fibrous structure as compared to modelling PDL as a layer of solid material. The results show that the tension-only nature of the fibres essentially suspends the tooth in the tooth socket and their inclusion in FE models makes a significant difference to both the magnitude and distribution of strains produced in the surrounding bone. The results indicate that the PDL fibres have a very important role in load transfer between the teeth and alveolar bone and should be considered in FE studies investigating the biomechanics of orthodontic tooth movement. PMID:25036099

  1. QUALITATIVE EVALUATION OF MARKETED AYURVEDIC RED TOOTH POWDER BY NAMBURI PHASED SPOT TEST

    Directory of Open Access Journals (Sweden)

    Satadru Palbag

    2013-03-01

    Full Text Available Simple and precise quality control analysis of consumer goods is the goal of rising FMCG sector. Ayurvedic red tooth powders are one of the most popular FMCG products in today’s market. The main ingredient (?80% of these red tooth powders is Swarna gairik (Red Hematite, thus the qualitative evaluation of red tooth powder can be performed by analysis of Swarna gairik. Objective of present study is to develop a simple yet precise method for the quality evaluation of Ayurvedic red tooth powders. Three marketed samples of red tooth powders S-1, S-2 and S-3 were evaluated by Namburi phased spot test against a control sample C. The variation of color and pattern of the spots were carefully evaluated at three distinct time phases. There were marked differences among the color and pattern of the spots for all the three samples when compared with the control, C. Study revealed that S-1 contains standard Swarna gairik whereas S-2 and S-3 contains spurious Swarna gairik. We concluded that the NST is a simple and dependable technique for the evaluation of Ayurvedic red tooth powder.

  2. Tooth loss prevalence and risk indicators in an isolated population of Brazil

    DEFF Research Database (Denmark)

    Corraini, Priscila; Baelum, Vibeke

    2009-01-01

    Objective . The aim of this study was to assess the prevalence, extent, and risk indicators of tooth loss in an isolated population of Brazil. Material and methods. Two-hundred-and-forty-two subjects, ranging in age from 14 to 82 years (mean 36.2 years), were identified by census in an isolated population of Brazil. All consenting subjects received a full-mouth clinical (DFT index and information about missing teeth) and periodontal examination of 6 sites per tooth. Furthermore, they were interviewed using a structured written questionnaire in order to gather information about demographic, environmental, and biological variables. Results . Of the 200 subjects (80% response rate), 19 (9.5%) were edentulous, 90% had lost at least one tooth, and 39% had lost more than 8 teeth. The mean number of teeth lost was 9.5 (95% CI=8.2-10.8). First mandibular molars were the most commonly missing teeth. In a multiple logistic regression analysis based on a theoretical hierarchical model of tooth loss, having more than 8 teeth lost was strongly associated with adult age (OR=18.3-17.3, 95% CIs=4.8-69.7 and 4.0-75.1) and female gender (OR=5.9, 95% CI=1.9-18.2) in the final model. Conclusions. Tooth loss was highly prevalent and extensive in this isolated population. Demographic and behavioral factors played an important role in tooth loss prevalence in this population.

  3. Conversion from tooth enamel dose to organ doses for electron spin resonance dosimetry

    International Nuclear Information System (INIS)

    Conversion from tooth enamel dose to organ doses was analyzed to establish a method of retrospective individual dose assessment against external photon exposure by electron spin resonance (ESR) dosimetry. Dose to tooth enamel was obtained by Monte Carlo calculations using a modified MIRD-type phantom with a teeth part. The calculated tooth enamel doses were verified by measurements with thermo-luminescence dosimeters inserted in a physical head phantom. Energy and angular dependences of tooth enamel dose were compared with those of other organ doses. Additional Monte Carlo calculations were performed to study the effect of human model on the tooth enamel dose with a voxel-type phantom, which was based on computed tomography images of the physical phantom. The data derived with the modified MIRD-type phantom were applied to convert from tooth enamel dose to organ doses against external photon exposure in a hypothesized field, where scattered radiation was taken into account. The results indicated that energy distribution of photons incident to a human body is required to evaluate precisely an individual dose based on ESR dosimetry for teeth. (author)

  4. Extraction method

    International Nuclear Information System (INIS)

    Definitions of the basic terms and of relations are given and the knowledge is described of the possibilities of the extraction of elements, oxides, covalent-bound halogenides and heteropolyacids. Greatest attention is devoted to the detailed analysis of the extraction of chelates and ion associates using diverse agents. For both types of compounds detailed conditions are given of the separation and the effects of the individual factors are listed. Attention is also devoted to extractions using mixtures of organic agents, the synergic effects thereof, and to extractions in non-aqueous solvents. The effects of radiation on extraction and the main types of apparatus used for extractions carried out in the laboratory are described. (L.K.)

  5. The influence of size and structure of metal orthodontic bracket base on bond strength on tooth enamel

    Directory of Open Access Journals (Sweden)

    Miti? Vladimir

    2009-01-01

    Full Text Available Introduction. The factors which may influence the bond strength of the applied orthodontic brackets on the tooth surface are the size and structure of the bracket base. Objective. The aim of the paper was to investigate the influence of size and shape of different types of brackets on bond strength on the enamel and analyze the remaining quality of adhesive material on the tooth surface after debonding of orthodontic brackets (adhesive remnant index - ARI. Methods. In this study, three types of metal brackets of different sizes and shapes of Dentaurum manufacturer were used (Utratrimm, Equilibrium 2, Discovery, Dentaurum, Inspringen, Germany. The brackets were applied onto the middle part of the anatomic crowns of buccal surfaces of 30 premolars extracted for orthodontic reasons. In addition, the pre-treatment of teeth by 37% orthophosphoric acid and adhesive material System1+ (Dentaurum, Germany were used. Results. The mean value of the bonded brackets bond strength of Discovery type after debonding was 8.67±0.32 MPa, while the value of the bonded brackets bond strength of Equilibrium 2 type amounted to 8.62±0.22 MPa. The value of the bonded brackets bond strength of Ultratrimm type after debonding was 8.22±0.49 MPa. There were no statistical differences in the values of bond strength regarding all three groups of the investigated orthodontic brackets (F=4.56; p<0.05. Conclusion. The base size and design of metal orthodontic brackets did not play a significant role in bond strength, while the values of ARI index were identical in all three investigated groups.

  6. In vitro assessment of the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains

    Directory of Open Access Journals (Sweden)

    Débora Alves Nunes Leite Lima

    2008-06-01

    Full Text Available This in vitro study evaluated the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains. Twenty dental blocks (4 x 4 mm, including enamel and dentine, removed from freshly extracted bovine incisors, were randomly divided into 4 groups: G1 - distilled water, G2 - Colgate, G3 - Crest Extra Whitening and G4 - Rapid White. In all specimens, the dentin was covered with colorless nail polish, and the enamel was left exposed. Next, the specimens were immersed in a solution of black tea, which was changed every 24 h, for a period of 6 days. After this period, a photo-reflectance reading was taken (Time 1 with a spectrometer. The stained specimens were then submitted to linear brushing movements (5,000 cycles using brushes (Oral B-Soft coupled to an automatic toothbrushing machine, under a static axial load of 200 g and with a speed of 4 movements/second, at 37°C, with the dentifrice or water being injected every 60 s. When toothbrushing ended, a second photo-reflectance reading was taken (Time 2. The results were submitted to two-criteria analysis of variance (ANOVA and to the Tukey test ( = 0.05. When the two times for a same group were compared, Time 2 presented the highest reflectance values with statistical difference only for G3 and G4. Among the dentifrices tested, only the Rapid White group differed from the control group, presenting the highest reflectance values. Only the whitening dentifrice Rapid White was effective for the removal of extrinsic stains.

  7. In vitro assessment of the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains

    Scientific Electronic Library Online (English)

    Débora Alves Nunes Leite, Lima; André Luís Faria e, Silva; Flávio Henrique Baggio, Aguiar; Priscila Christiane Suzy, Liporoni; Egberto, Munin; Gláucia Maria Bovi, Ambrosano; José Roberto, Lovadino.

    2008-06-01

    Full Text Available This in vitro study evaluated the effectiveness of whitening dentifrices for the removal of extrinsic tooth stains. Twenty dental blocks (4 x 4 mm), including enamel and dentine, removed from freshly extracted bovine incisors, were randomly divided into 4 groups: G1 - distilled water, G2 - Colgate, [...] G3 - Crest Extra Whitening and G4 - Rapid White. In all specimens, the dentin was covered with colorless nail polish, and the enamel was left exposed. Next, the specimens were immersed in a solution of black tea, which was changed every 24 h, for a period of 6 days. After this period, a photo-reflectance reading was taken (Time 1) with a spectrometer. The stained specimens were then submitted to linear brushing movements (5,000 cycles) using brushes (Oral B-Soft) coupled to an automatic toothbrushing machine, under a static axial load of 200 g and with a speed of 4 movements/second, at 37°C, with the dentifrice or water being injected every 60 s. When toothbrushing ended, a second photo-reflectance reading was taken (Time 2). The results were submitted to two-criteria analysis of variance (ANOVA) and to the Tukey test ( = 0.05). When the two times for a same group were compared, Time 2 presented the highest reflectance values with statistical difference only for G3 and G4. Among the dentifrices tested, only the Rapid White group differed from the control group, presenting the highest reflectance values. Only the whitening dentifrice Rapid White was effective for the removal of extrinsic stains.

  8. Decomposition of beta-ray induced ESR spectra of fossil tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Joannes-Boyau, Renaud, E-mail: renaud.joannes-boyau@anu.edu.a [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia); Gruen, Rainer [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia)

    2011-03-15

    Two fossil tooth enamel fragments were irradiated with beta rays, one through the outer surface, the other through the dentine-enamel junction. The angular ESR spectra of the two fragments were decomposed using an automated simulated annealing (SA) procedure, which is particularly well suited to separate overlapping signals. Beta irradiation generated different qualitative and quantitative responses to previous gamma irradiation experiments. Similar to gamma rays, the beta irradiation created both non-oriented and oriented CO{sub 2}{sup -} radicals. In contrast to gamma irradiation, which only created orthorhombic oriented CO{sub 2}{sup -} radicals, both axial and orthorhombic CO{sub 2}{sup -} radicals were extracted after beta irradiation. Furthermore, gamma irradiation created significantly more non-oriented radicals than beta irradiation. Altogether, the radical distribution created by beta irradiation resembled that of the natural sample, which had been exposed to environmental irradiation over several hundreds of thousands of years. The natural sample contained 9% non-orientated CO{sub 2}{sup -} radicals and a mix of orthorhombic to axial CO{sub 2}{sup -} radicals in the ratio of 35:65. The beta induced spectra of the fragment irradiated through the outer surface contained 9% non-orientated CO{sub 2}{sup -} radicals and a mix of orthorhombic to axial CO{sub 2}{sup -} radicals in the ratio of 45:55, while for the other sample these values were 19% and 59:41, respectively. The angle between the axial and orthorhombic CO{sub 2}{sup -} radicals is around 23{sup o} in both natural and beta irradiation components. This indicates that the radicals produced by the different irradiation modes are located in the same positions in the hydroxyapatite crystals. The higher percentage of non-oriented CO{sub 2}{sup -} radicals closer to the dentine-enamel junction points to interprismatic zones for their possible location.

  9. Myelin protein zero gene sequencing diagnoses Charcot-Marie-Tooth Type 1B disease

    Energy Technology Data Exchange (ETDEWEB)

    Su, Y.; Zhang, H.; Madrid, R. [Univ. of California, San Francisco, CA (United States)] [and others

    1994-09-01

    Charcot-Marie-Tooth disease (CMT), the most common genetic neuropathy, affects about 1 in 2600 people in Norway and is found worldwide. CMT Type 1 (CMT1) has slow nerve conduction with demyelinated Schwann cells. Autosomal dominant CMT Type 1B (CMT1B) results from mutations in the myelin protein zero gene which directs the synthesis of more than half of all Schwann cell protein. This gene was mapped to the chromosome 1q22-1q23.1 borderline by fluorescence in situ hybridization. The first 7 of 7 reported CMT1B mutations are unique. Thus the most effective means to identify CMT1B mutations in at-risk family members and fetuses is to sequence the entire coding sequence in dominant or sporadic CMT patients without the CMT1A duplication. Of the 19 primers used in 16 pars to uniquely amplify the entire MPZ coding sequence, 6 primer pairs were used to amplify and sequence the 6 exons. The DyeDeoxy Terminator cycle sequencing method used with four different color fluorescent lables was superior to manual sequencing because it sequences more bases unambiguously from extracted genomic DNA samples within 24 hours. This protocol was used to test 28 CMT and Dejerine-Sottas patients without CMT1A gene duplication. Sequencing MPZ gene-specific amplified fragments identified 9 polymorphic sites within the 6 exons that encode the 248 amino acid MPZ protein. The large number of major CMT1B mutations identified by single strand sequencing are being verified by reverse strand sequencing and when possible, by restriction enzyme analysis. This protocol can be used to distringuish CMT1B patients from othre CMT phenotypes and to determine the CMT1B status of relatives both presymptomatically and prenatally.

  10. EFFECTS OF POLISHING TIME AND THERMALCYCLINGON THE MICROLEAKAGE OF FOUR TOOTH –COLOURED DIRECT RESTORATIVE MATERIALS

    Directory of Open Access Journals (Sweden)

    V MORTAZAVI

    2002-09-01

    Full Text Available Introdaction. Microleakage has been recognized as a major clinical problem with direct filled dental restorations.The purpose of this study was to investigate and to compare the microleakage of four direct filled tooth-coloured materials, evaluation the effects of polishing time and thermocycling on the microleakage of these materials. Methods. Wedge-shaped class V cavities were prepared on buccal and lingual surfaces of 96 intact extracted human molar teeth. The teeth were randomly divided into three treatment groups and four subgroups. The cavities of each subgroup were filled using one of these materials: a conventional glass ionomer; a resin modified glass ionomer; a composite resin and a compomer. Polishing in the teeth of group 1 was done immediately after placement of restorations and in group 2 one week later. In group 3 delayed polishing and thermocycling (X100 was done. All of the teeth were stored in distilled water for one week and then stained with dye, sectioned, and scored for microleakage on occlusal and cervical edges. Results were statistically analyzed by Kruskal wallis and Mann whitney tests. Results. There was a statistically difference between the microleakage scores of four materials (P < 0.001. Immediately polished glass ionomer and compomer groups have significantly more microleakage than delayed polished groups (P < 0.001. Thermocycting could infulence the microleakage of composite on cervical edges (P < 0.05. Discussion. The precense of differences between the nature of materials and also the surface treatment such as primer or etchant application could influence the microleakage. The prescence of differences in reaction rate between the materials and the time that they reach to their adequate mechanical strength and adhesive bond strength lead to presence of differences between the effect of polishing time on the microleakage scores of materials.

  11. Relics as paleopathological evidence from the past – tooth relics

    Directory of Open Access Journals (Sweden)

    A. Petaros

    2011-12-01

    Full Text Available Relics represent ancient religious objects held in Churches or religious institutions for the purposes of veneration. They most often refer to the bodily remnants (mummified or not of Saints. The importance they have retained in history is great (they were used as talismans in battles, as well to strengthen alliances or heal the sick and still today religious people attach great importance to them. The aim of this article is to present the historical and paleopathological importance of relics, which have been poorly targeted through history. Among different types of relics the most significant tooth relics of three great religions will be presented: that of St. Apollonia, Buddha and Prophet Mohammed. Some of the most important invasive and non-invasive paleopathological studies conducted on relics (including teeth relics are cited. The article concludes that there is a need for more research on Saints’ relics, although religious constraints and other limitations are present. Results published to date have shown how targeted and well-organized research can yield important and interesting information about the life and environment of the Saint, as well attest the authenticity of the analyzed remains. The article also points out the need to establish a database of relics and how the anthropological and paleopathological data recovered from their analysis would, while preserving their sanctity, improve our knowledge on the topic and add new osteobiographic data to the known written facts about a specific Saint.

  12. Tooth width predictions in a sample of Black South Africans.

    Science.gov (United States)

    Khan, M I; Seedat, A K; Hlongwa, P

    2007-07-01

    Space analysis during the mixed dentition requires prediction of the mesiodistal widths of the unerupted permanent canines and premolars and prediction tables and equations may be used for this purpose. The Tanaka and Johnston prediction equations, which were derived from a North American White sample, is one example which is widely used. This prediction equation may be inapplicable to other race groups due to racial tooth size variability. Therefore the purpose of this study was to derive prediction equations that would be applicable to Black South African subjects. One hundred and ten pre-treatment study casts of Black South African subjects were analysed from the Department of Orthodontics' records at the University of Limpopo. The sample was equally divided by gender with all subjects having Class I molar relationship and relatively well aligned teeth. The mesiodistal widths of the maxillary and mandibular canines and premolars were measured with a digital vernier calliper and compared with the measurements predicted with the Tanaka and Johnston equations. The relationship between the measured and predicted values were analysed by correlation and regression analyses. The results indicated that the Tanaka and Johnston prediction equations were not fully applicable to the Black South African sample. The equations tended to underpredict the male sample, while slight overprediction was observed in the female sample. Therefore, new equations were formulated and proposed that would be accurate for Black subjects. PMID:17927030

  13. Resorptive tooth root lesions in the Malayan tapir (Tapirus indicus).

    Science.gov (United States)

    Da Silva, Mari-Ann O; Kortegaard, Hanne E; Choong, Siew Shean; Arnbjerg, Jens; Bertelsen, Mads F

    2011-03-01

    Facial abscessation and osteomyelitis due to dental disease is commonly seen in the Malayan tapir (Tapirus indicus), but little is known about the prevalence or etiology of these lesions. To determine the prevalence of dental ailments, 56 skulls and mandibles of deceased Malayan tapirs were visually and radiographically evaluated. Dental lesions were scored according to severity, and individuals were classified according to their age (juvenile/ young adult/adult) and origin (captive/free ranging). All of the lesions identified were of a resorptive nature. seemingly originating at the cementoenamel junction and burrowing towards the center of the tooth. Overall, 27% of the investigated skulls presented radiolucent dental lesions. The prevalence among captive animals was 52% (13/25), while only 6% (2/31) of the free-ranging tapirs had dental lesions. The second, third, and fourth premolars and first molar were the teeth most commonly affected, and the mandibular teeth were more often involved than the maxillary dentition. This study demonstrates a high prevalence of resorptive dental lesions in captive Malayan tapirs and provides a strong indication that age and captivity are significant risk factors in the development of these lesions. Dental disease, Malayan tapir, radiology, resorptive lesions, Tapirus indicus. PMID:22946368

  14. Achievable Precision and Accuracy in EPR Dosimetry of Tooth Enamel

    International Nuclear Information System (INIS)

    The utility of combining various methodologies is examined to remove systematically or correct for the major instrumental effects which introduce uncertainties in EPR dosimetry of tooth enamel. The result is a relatively high precision method that can be successfully transferred between laboratories. Only an ideal case was considered in this study whereby the actual native signal prior to irradiation was used as the empirical zero in each individual dose response. To prove its general value, the overall methodology was applied to seven teeth of differing quality, prepared using different methodologies, and measured in three laboratories using different EPR spectrometers. Using this approach to characterise the utility of both the methodology and instrumentation resulted in 5 ± 5 mGy (1?) spectral intensity reproducibility at the 100 mGy dose level for the seven samples analysed. Similarly, at the 1100 mGy level, spectral intensity reproducibility was found to be equivalent to 13 ± 5 mGy (1?) for the same seven samples. Assuming linearity of dose response in the 0-1100 mGy dose range and using dose responses at 100 mGy and 1100 mGy levels, gave an overall extrapolated x intercept (dose estimate) offset of -13 ± 19 mGy (1?) (author)

  15. Mutation testing in Charcot-Marie-Tooth neuropathy.

    Science.gov (United States)

    Nicholson, G A

    1999-09-14

    In order to determine the optimal approach for mutation testing in the form of Charcot-Marie-Tooth (CMT) neuropathy, consecutive patients with a CMT phenotype, available family history information on at least first-degree relatives, and median motor conduction velocities of less than 50 m/sec were tested for the CMT1A duplication and for connexin32, peripheral myelin protein 22 (PMP22) and myelin protein zero (P0) point mutations. A cutoff value for median motor conduction velocity of less than 50 m/sec was adopted to include all CMTX families. All of the connexin32 mutations, except for one sporadic case, were found by first selecting families with no male-to-male inheritance of CMT and neurophysiological indicators of CMTX. All PMP22 and P0 mutations were found by selecting Dejerine-Sottas cases or dominantly inherited CMT1 with a very severe phenotype. It is concluded that "blind" testing of CMT1 families for connexin32, P0, and PMP22 mutations is of limited value. PMID:10586262

  16. Tooth morphology of the maned sloth (Bradypus torquatus

    Directory of Open Access Journals (Sweden)

    Edson Benetti

    2006-12-01

    Full Text Available The sloths are exclusively herbivores, feeding from leaves, flowers, sprouts, green stalks and fruits, just from two types of tree. The aim of this research was to explore the anatomy of the teeth comparing them with those of other mammals, besides those of man. Twelve animals were used, including males, females and stillborns, all of the species Bradypus torquatus. Macroscopic and radiographic exams were carried out, complemented by light microscopic technique of wasted and decalcification and scanning electron microscopy to analyses ultra structure components. The sloths are born with teeth already, presenting in each hemiarcade five teeth in the jawbone and four in the jaw, totaling eighteen in all. The morphology of the tooth in these specimens is strongly related to the alimentary habits and the whole dental arch (maxilla and jaw, presenting teeth with a similar shape and indicating that dental specialization does not exist. The teeth present lingual, vestibular, distal, mesial and occlusal faces, and the presence of "peaks” is marked. The components of the teeth are cement, internal, and external dentine and pulp. It is possible to identify tissue located between the cement and the external dentine containing tubules, which are continuous with those of the external dentine and the vascular channels of the internal dentine. This investigation can assist the search for answers as to what constitutes an appropriate alimentary diet for the animals in captivity.

  17. Tooth loss in individuals under periodontal maintenance therapy: prospective study

    Scientific Electronic Library Online (English)

    Telma Campos Medeiros, Lorentz; Luís Otávio Miranda, Cota; José Roberto, Cortelli; Andréia Maria Duarte, Vargas; Fernando Oliveira, Costa.

    2010-06-01

    Full Text Available This prospective study aimed to evaluate the incidence, the underlying reasons, and the influence of predictors of risk for the occurrence of tooth loss (TL) in a program of Periodontal Maintenance Therapy (PMT). The sample was composed of 150 complier individuals diagnosed with chronic moderate-sev [...] ere periodontitis who had finished active periodontal treatment and were incorporated in a program of PMT. Social, demographic, behavioral and biological variables were collected at quarterly recalls, over a 12-month period. The effect of predictors of risk of and confounding for the dependent variable TL was tested by univariate and multivariate analysis, as well as the underlying reasons and the types of teeth lost. During the monitoring period, there was a considerable improvement in periodontal clinical parameters, with a stability of periodontal status in the majority of individuals. Twenty-eight subjects (18.66%) had TL, totaling 47 lost teeth (1.4%). The underlying reasons for TL were: periodontal disease (n = 34, 72.3%), caries (n = 3, 6.4%), prosthetic reasons (n = 9, 19.2%), and endodontic reasons (n = 1, 2.1%). Additionally, subjects with 10% of sites with probing depth between 4 and 6 mm were 5 times more likely to present TL (OR = 5.13, 95% CI 2.04-12.09). In this study, the incidence of TL was small and limited to few individuals. Additionally, gender and severity of periodontitis were significantly associated with TL during the monitoring period.

  18. Charcot-marie-tooth disease: seventeen causative genes.

    Science.gov (United States)

    Lee, Jung-Hwa; Choi, Byung-Ok

    2006-06-01

    Charcot-Marie-Tooth disease (CMT) is the most common form of inherited motor and sensory neuropathy. Moreover, CMT is a genetically heterogeneous disorder of the peripheral nervous system, with many genes identified as CMT-causative. CMT has two usual classifications: type 1, the demyelinating form (CMT1); and type 2, the axonal form (CMT2). In addition, patients are classified as CMTX if they have an X-linked inheritance pattern and CMT4 if the inheritance pattern is autosomal recessive. A large amount of new information on the genetic causes of CMT has become available, and mutations causing it have been associated with more than 17 different genes and 25 chromosomal loci. Advances in our understanding of the molecular basis of CMT have revealed an enormous diversity in genetic mechanisms, despite a clinical entity that is relatively uniform in presentation. In addition, recent encouraging studies - shown in CMT1A animal models - concerning the therapeutic effects of certain chemicals have been published; these suggest potential therapies for the most common form of CMT, CMT1A. This review focuses on the inherited motor and sensory neuropathy subgroup for which there has been an explosion of new molecular genetic information over the past decade. PMID:20396492

  19. Pé cavo adquirido na doença de Charcot-Marie-Tooth / Acquired pes cavus in Charcot-Marie-Tooth disease

    Scientific Electronic Library Online (English)

    Daniel Augusto Carvalho, Maranho; José Batista, Volpon.

    Full Text Available As neuropatias sensitivomotoras hereditárias, principalmente a doença de Charcot-Marie-Tooth, manifestam-se frequentemente com o aparecimento de pé cavovaro, deformidade caracterizada pela acentuação fixa do arco plantar e inversão do retropé. O diagnóstico da doença de base e a cuidadosa avaliação [...] do paciente fornecem os elementos-chave para decisão do tratamento. O cavo pode situar-se no antepé, retropé ou ser o resultado da associação das duas localizações. Deformidades combinadas, principalmente varismo e garras dos artelhos, devem ser bem avaliadas; as características clínicas como grau das alterações, acometimento da força muscular, flexibilidade e idade são fatores importantes para a decisão da conduta. O tratamento conservador do pé cavovaro por meio de fisioterapia, palmilhas e adaptação nos calçados é reservado ao paciente mais jovem ou casos levemente acometidos. Entretanto, há tendência de agravamento das deformidades devido à característica progressiva da doença neurológica de base. Assim, o tratamento cirúrgico pelas técnicas clássicas é indicado precocemente, sendo importante identificar as alterações primárias, diferenciá-las das secundárias e corrigi-las, se possível. As transferências musculares são usadas no sentido de minimizar o desequilíbrio, estruturas retraídas são seccionadas ou alongadas e osteotomias localizadas devem ser preferíveis às artrodeses, que são reservadas para pés rígidos e muito deformados de pacientes adultos. Abstract in english Hereditary motor and sensory neuropathies, especially Charcot-Marie-Tooth disease, are frequently expressed with an acquired cavusvarus foot which is characterized by a fixed increase of the plantar arch and hindfoot inversion. Diagnosis of the underlying condition achieved through careful patient a [...] ssessment and local evaluations is the keystone for decision-making about the adequate treatment. The cavus may present as an isolated deformity of the forefoot, hindfoot or it may be a combination of both locations. Related deformities, mainly the varus and toe clawing require appropriate evaluation; clinical characteristics such as severity of the deformity, impairment of the muscular power, flexibility and patient's age are important characteristics in the treatment decision. Conservative treatment of the cavusvarus foot with physiotherapy, insoles and shoe modifications are reserved to young patients and mild deformities. However, there is a tendency of the deformity to become more severe over time because of the progressive feature of the underlying neurological condition. So, the surgical treatment by using classical techniques is performed in early stages. Most importantly is the identification of the primary and main components of each deformity to properly correct them, if possible. Muscular transfers are used to treat the dynamic unbalance, retracted structures should be either divided or lengthened and localized osteotomies should be preferred over arthrodeses, which are reserved for stiff and severely deformed feet in adults.

  20. Pé cavo adquirido na doença de Charcot-Marie-Tooth Acquired pes cavus in Charcot-Marie-Tooth disease

    Directory of Open Access Journals (Sweden)

    Daniel Augusto Carvalho Maranho

    2009-01-01

    Full Text Available As neuropatias sensitivomotoras hereditárias, principalmente a doença de Charcot-Marie-Tooth, manifestam-se frequentemente com o aparecimento de pé cavovaro, deformidade caracterizada pela acentuação fixa do arco plantar e inversão do retropé. O diagnóstico da doença de base e a cuidadosa avaliação do paciente fornecem os elementos-chave para decisão do tratamento. O cavo pode situar-se no antepé, retropé ou ser o resultado da associação das duas localizações. Deformidades combinadas, principalmente varismo e garras dos artelhos, devem ser bem avaliadas; as características clínicas como grau das alterações, acometimento da força muscular, flexibilidade e idade são fatores importantes para a decisão da conduta. O tratamento conservador do pé cavovaro por meio de fisioterapia, palmilhas e adaptação nos calçados é reservado ao paciente mais jovem ou casos levemente acometidos. Entretanto, há tendência de agravamento das deformidades devido à característica progressiva da doença neurológica de base. Assim, o tratamento cirúrgico pelas técnicas clássicas é indicado precocemente, sendo importante identificar as alterações primárias, diferenciá-las das secundárias e corrigi-las, se possível. As transferências musculares são usadas no sentido de minimizar o desequilíbrio, estruturas retraídas são seccionadas ou alongadas e osteotomias localizadas devem ser preferíveis às artrodeses, que são reservadas para pés rígidos e muito deformados de pacientes adultos.Hereditary motor and sensory neuropathies, especially Charcot-Marie-Tooth disease, are frequently expressed with an acquired cavusvarus foot which is characterized by a fixed increase of the plantar arch and hindfoot inversion. Diagnosis of the underlying condition achieved through careful patient assessment and local evaluations is the keystone for decision-making about the adequate treatment. The cavus may present as an isolated deformity of the forefoot, hindfoot or it may be a combination of both locations. Related deformities, mainly the varus and toe clawing require appropriate evaluation; clinical characteristics such as severity of the deformity, impairment of the muscular power, flexibility and patient's age are important characteristics in the treatment decision. Conservative treatment of the cavusvarus foot with physiotherapy, insoles and shoe modifications are reserved to young patients and mild deformities. However, there is a tendency of the deformity to become more severe over time because of the progressive feature of the underlying neurological condition. So, the surgical treatment by using classical techniques is performed in early stages. Most importantly is the identification of the primary and main components of each deformity to properly correct them, if possible. Muscular transfers are used to treat the dynamic unbalance, retracted structures should be either divided or lengthened and localized osteotomies should be preferred over arthrodeses, which are reserved for stiff and severely deformed feet in adults.