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.
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...
Tozoglu Sinan; Gungormus Metin; Buyukkurt Cemil M.; Yavuz Selim M.
Bell's palsy is characterized by acute peripheral facial nerve paralysis. Unilateral paralysis of CN 7 is reported in 20 to 30 people out of 100,000 in the general population. It affects individuals of all ages. Most cases are idiopathic, while a few are identified as resulting from infectious or non-infectious causes. The association between herpes simplex virus-1 (HSV-1) and Bell's palsy has been considered since the 1970s. Few cases have been reported after tooth extraction. PMID:22803274
Owsley, David; Goldsmith, Jay P
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.
This report presents a therapeutic approach to orthodontic tooth extraction in a patient at high risk for the development of osteoradionecrosis with conventional techniques. The rationale for this procedure is discussed in detail, combining principles of radiation biology, clinical radiation therapy, and biomechanics of tooth movement
The purpose of this study was to determine the anesthetic efficacy of a intraosseous anesthesia (IOA) as an alternative to the infra alveolar nerve block (IANB) or the maxillary anesthesia. 55 subjects who underwent a tooth extraction received a primary X-tip intraosseous injection (LLC Lakewood, New Jersey, U.S.A.) of Ubistesin forte (articaini hydrochloridum 40 mg, adrenalinum 10 pg ut adrenalini hydrochloridum 1:100000, median 1.5 ml). A pulse oximeter measured the heart rate and the oxygen saturation. The results demonstrated, that the maximum heart rate was higher with the intraosseous injection (average 14.6 beats/min increase) during 1.5-2 minutes, but there was no depression of the oxygen saturation. The wound healing was uneventful. We registered five non-responders which were treated additionally with 1.3 ml of Ubistesin forte terminal anesthesia. For all patients the IOA was unpleasant similar to a "normal" anesthesia. Success of the intraosseous injection was 91%, comparable to the study of Turner et al. (2002) (or the clinical experience after an IANB). For non-responders to an IANB the IOA seems to be a good alternative method. PMID:19785249
Augello, Marcello; Furrer, Thomas; Locher, Michael
Clinical courses following two-stage mandibular wisdom tooth extraction (TMWTE) carried out for preventing postoperative mental nerve paresthesia (MNP) were analyzed. When panoramic X-ray showed overlapping of wisdom tooth root on the superior 1/2 or more of the mandibular canal, interruption of the white line of the superior wall of the canal, or diversion of the canal, CT examination was facilitated. In cases where contact between the tooth root and canal was demonstrated in CT examination, TMWTE was then selected after gaining the patient's consent. TMWTE consisted of removing more than a half of the tooth crown and tooth root extraction at the second step after 2-3 months. The clinical features of wisdom teeth extracted and postoperative courses including tooth movement and occurrence of MNP during two-stage MWTE were evaluated. TMWTE was carried out for 40 teeth among 811 wisdom teeth (4.9%) that were extracted from 2007 to 2009. Among them, complete procedures were accomplished in 39 teeth, and crown removal was performed insufficiently at the first-stage operation in one tooth. Tooth movement was detected in 37 of 40 cases (92.5%). No postoperative MNP was observed in cases in which complete two-stage MWTE was carried out, but one case with insufficient crown removal was complicated by postoperative MNP. Seven mild complications (dehiscence, cold sensitivity, etc.) were noted after the first-stage operation. Therefore, we conclude that TMWTE for high-risk caseswe conclude that TMWTE for high-risk cases assessed by X-ray findings is useful to avoid MNP after MWTE. (author)
Background. Maxillary tuberosity during teeth extraction can occur in dental practice. The aim of this paper was to present a case of the maxillary tuberosity fracture occurred during tooth extraction, which was the subject of the forensic expertise. Case report. The maxillary tuberosity fracture created during the extraction of the upper molar was neither timely nor adequately managed by the doctor who started extraction. After the treatment at the specialist institution, the patient sued th...
Puzovi? Dragana; ?oli? Snježana
Full Text Available Accelerating wound healing after tooth extraction is beneficial in dental treatment. Application of antioxidants, such as reduced coenzyme Q10 (rCoQ10, may promote wound healing after tooth extraction. In this study, we examined the effects of topical application of rCoQ10 on wound healing after tooth extraction in rats. After maxillary first molars were extracted, male Fischer 344 rats (8 weeks old (n = 27 received topical application of ointment containing 5% rCoQ10 (experimental group or control ointment (control group to the sockets for 3 or 8 days (n = 6–7/group. At 3 days after extraction, the experimental group showed higher collagen density and lower numbers of polymorphonuclear leukocytes in the upper part of socket, as compared to the control group (p < 0.05. Gene expression of interleukin-1?, tumor necrosis factor-? and nuclear factor-?B were also lower in the experimental group than in the control group (p < 0.05. At 8 days after tooth extraction, there were no significant differences in collagen density, number of polymorphonuclear leukocytes and bone fill between the groups. Our results suggest that topical application of rCoQ10 promotes wound healing in the soft tissue of the alveolar socket, but that rCoQ10 has a limited effect on bone remodeling in rats.
Accelerating wound healing after tooth extraction is beneficial in dental treatment. Application of antioxidants, such as reduced coenzyme Q10 (rCoQ10), may promote wound healing after tooth extraction. In this study, we examined the effects of topical application of rCoQ10 on wound healing after tooth extraction in rats. After maxillary first molars were extracted, male Fischer 344 rats (8 weeks old) (n = 27) received topical application of ointment containing 5% rCoQ10 (experimental group) or control ointment (control group) to the sockets for 3 or 8 days (n = 6–7/group). At 3 days after extraction, the experimental group showed higher collagen density and lower numbers of polymorphonuclear leukocytes in the upper part of socket, as compared to the control group (p < 0.05). Gene expression of interleukin-1?, tumor necrosis factor-? and nuclear factor-?B were also lower in the experimental group than in the control group (p < 0.05). At 8 days after tooth extraction, there were no significant differences in collagen density, number of polymorphonuclear leukocytes and bone fill between the groups. Our results suggest that topical application of rCoQ10 promotes wound healing in the soft tissue of the alveolar socket, but that rCoQ10 has a limited effect on bone remodeling in rats. PMID:25514392
Yoneda, Toshiki; Tomofuji, Takaaki; Kawabata, Yuya; Ekuni, Daisuke; Azuma, Tetsuji; Kataoka, Kota; Kunitomo, Muneyoshi; Morita, Manabu
Full Text Available Background. Maxillary tuberosity during teeth extraction can occur in dental practice. The aim of this paper was to present a case of the maxillary tuberosity fracture occurred during tooth extraction, which was the subject of the forensic expertise. Case report. The maxillary tuberosity fracture created during the extraction of the upper molar was neither timely nor adequately managed by the doctor who started extraction. After the treatment at the specialist institution, the patient sued the doctor for the criminal offense of negligent treatment. The task of the expert was to give a professional answer to the question whether the doctor, who caused a maxillary tuberosity fracture during the tooth extraction, acted negligently and applied inadequate treatment. Conclusion. The maxillary tuberosity fracture during molar extraction may be its complication. If it is diagnosed promptly, immediately and adequately managed, there is no possibility for negligence action.
The aim of the present study was to assess the efficacy of a ready-to-use injectable bone substitute on the prevention of alveolar ridge resorption after tooth extraction. Maxillary and mandibular premolars were extracted from 3 Beagle dogs with preservation of alveolar bone. Thereafter, distal sockets were filled with an injectable bone substitute (IBS), obtained by combining a polymer solution and granules of a biphasic calcium phosphate (BCP) ceramic. As a control, the mesial sockets were ...
Boix, Damien; Weiss, Pierre; Gauthier, Olivier; Guicheux, Je?ro?me; Bouler, Jean-michel; Pilet, Paul; Daculsi, Guy; Grimandi, Gae?l
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.
Yugoshi Luciana Ibara
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.
Full Text Available A 66-year-old gentleman with a history Friedreich’s ataxia underwent a dental extraction procedure just prior to 4 weeks of traveling abroad. He was seen in emergency room for increasing weakness, cough and low grade fevers. His chest x-ray revealed a foreign body in the right main bronchus (Figure 1. He underwent bronchoscopy with forceps and basket removal of partially impacted teeth from the bronchus intermedius (Figure 2.
The objective of this retrospective clinical study was to determine the frequency and pathogenicity of unintentional retained tooth root fragments after extraction of the maxillary fourth premolar (108 and 208) and mandibular first molar teeth (309 and 409) in 74 canine and 42 feline client-owned patients. Radiographs of client-owned animals with historical evidence of extraction of teeth 309 and 409 were reviewed. All patients had dental extraction(s) for clinical reasons, and all extractions were deemed successful by the practitioners. Extraction sites were radiographed to identify tooth root fragments and pathology. Twenty-five canine and 25 feline patients that had extractions utilizing preoperative and postoperative radiography were also included. Sixty-one of 74 canine patients (82.4%; P?root fragments. In total, 100 of 116 cases (86.4%; P?root fragments, and periapical pathology was found in 66 of 116 (56.8%; P?=?0.000000743) radiographs, including 39 of 74 canine cases (52.7%; P?=?0.00002765) and 27 of 42 feline cases (64.3%; P?=?0.01589). The control group had no evidence of retained root fragments. Further veterinary dental training and routine use of pre- and postoperative dental radiology are recommended. PMID:24446405
Moore, James I; Niemiec, Brook
The intranasal tooth is a rare clinical phenomenon that has unclear etiology. It may result to rhinolith with deposition calcium and organic materials around the ectopic nasal tooth. In this report we presended 43-year-old female who had ectopic nasal tooth which seems to be rhinolith .Diagnose of ectopic nasal tooth was determined by radiological examination and it was extracted by endoscopically.
Full Text Available Background/Aim. Patients receiving long-term oral anticoagulant therapy pose a clinical challenge during invasive dental procedures. The goal of this study was to compare different local hemostatic modalities after tooth extraction in patients receiving chronic Vitamin-K antagonist therapy. Methods. Totally 90 patients with International Normalized Ratio (INR ? 3.0 requiring simple extraction of one or two teeth were randomized into three groups, 30 patients in each group. The patients with the mean INR value of 2.35 ± 0.37, in whom extraction wound was sutured comprised the group A. In the group B with the mean INR of 2.43 ± 0.4, local hemostasis was achieved by placing absorbable gelatin sponges into the wound without suturing. The group C consisted of the patients with the mean INR of 2.36 ± 0.34 in whom neither gelatin sponge nor suturing were used for providing local hemostasis. Bleeding was registered as an event if other than initial hemostatic measure was needed or additional oral surgeon intervention required. Results. The obtainded results show that 1 (3.3% patient in the group A, 2 (6.7% patients in the groups B and C manifested post-extraction bleeding. All cases of hemorrhage were easily solved with local hemostatic measures and all, except one case, were registered in the first two hours after the procedure until the dismissal. A difference between the groups was not statistically significant (?2 = .42, p > 0.05. Conclusion. In therapeutically anticoagulated patients tooth extractions can be safely performed without altering the dose of anticoagulant medication if efficient local hemostasis is provided. In most cases, in patients with INR ? 3.0 after extraction of one or two teeth postoperative bleeding can be controlled with local pressure, without any additional local hemostatic measures.
Bajkin Branislav V.
Full Text Available Ahmet Günay,1 Osman Fatih Arpa?,2 Serhat Atilgan,3 Ferhan Yaman,3 Yusuf Atalay,4 ?zzet Acikan3 1Department of Periodontology, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 2Department of Periodontology, Faculty of Dentistry, Mustafa Kemal University, Hatay, Turkey; 3Department of Maxillofacial Surgery, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 4Department of Maxillofacial Surgery, Faculty of Dentistry, Kocatepe University, Afyon, Turkey Aim: The purpose of this study was to evaluate the effects of caffeic acid phenethyl ester (CAPE on palatal mucosal defects and tooth extraction sockets in an experimental model.Materials and methods: Forty-two male Sprague-Dawley rats with a mean age of 7 weeks and weighing 280–490 g were used in this study. The rats were randomly divided into two groups: group A (the control group, n=21 and group B (the experimental group, n=21. Under anesthesia with ketamine (8 mg/100 g, intraperitoneally, palatal mucosal defects were created and tooth extraction was performed in the rats in groups A and B. Group A received no treatment, whereas group B received CAPE. CAPE was injected daily (10 µmol/kg, intraperitoneally. The rats were killed on days 7, 14, and 30 after the procedures. Palatal mucosa healing and changes in bone tissue and fibrous tissue were evaluated histopathologically.Result: Pairwise comparisons showed no statistically significant difference between days 7 and 14 in either group (P>0.05. At day 30, bone healing was significantly better in group B (CAPE than in group A (control (P<0.05. Fibrinogen levels at day 30 were significantly higher in group A (control than in group B (CAPE (P<0.05. Pairwise comparisons showed no statistically significant difference in palatal mucosa healing levels between days 7 and 14 in both groups (P>0.05.Conclusion: In conclusion, the findings of this study suggest that CAPE can significantly improve tooth socket healing. Keywords: caffeic acid phenyl ester, palatal mucosa, tooth extraction socket, healing
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. PMID:25031484
Badakhsh, Samaneh; Eskandarian, Tahereh; Esmaeilpour, Tahereh
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)
A five-year-old entire male Tibetan Terrier was referred for left-sided periorbital swelling and blepharospasm 4 days following ipsilateral maxillary tooth extraction. Examination of the left eye revealed mild exophthalmos, pain on retropulsion, and absent menace response and pupillary light reflexes. Examination of the posterior segment was not possible owing to the anterior segment pathology. Differential diagnoses considered were iatrogenic globe penetration and peribulbar abscess/cellulitis. Ocular ultrasound was consistent with a penetrating wound to the globe. Treatment with systemic prednisolone and marbofloxacin, and topical atropine sulfate 1%, prednisolone acetate, and brinzolamide was started. Marked clinical improvement allowed visual confirmation of the perforation. Oral prednisolone was tapered over the following 10 weeks. At final re-examination (10 months), the patient was visual, and fundic examination revealed an additional chorioretinal scar, most likely an exit wound that was obscured by vitreal debris on initial examinations. Neither scar was associated with retinal detachment. To the authors' knowledge, this is the first reported case of successful medical management of iatrogenic globe penetration following exodontic procedures. PMID:23869648
Guerreiro, Cleo E; Appelboam, Helen; Lowe, Robert C
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.
Srinivas N CH
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...
Ch, Srinivas N.; Jayanthi M; Shanthan
Dexmedetomidine is an ?2-adrenergic receptor agonist that causes minimal respiratory depression compared with alternative drugs. This study investigated whether combined dexmedetomidine/fentanyl offered better sedation and analgesia than midazolam/fentanyl in dental surgery. Sixty patients scheduled for unilateral impacted tooth extraction were randomly assigned to receive either dexmedetomidine and fentanyl (D/F) or midazolam and fentanyl (M/F). Recorded variables were patient preoperative anxiety scores, vital signs, visual analogue scale (VAS) pain scores, Observer's Assessment of Alertness/Sedation Scale (OAAS) scores after drug administration, surgeon and patient degree of satisfaction, and the duration of analgesia after surgery. The OAAS scores were significantly lower for patients administered D/F compared to those who received M/F. The duration of analgesia after the surgical procedure was significantly longer in patients who received D/F (5.3 h) than in those who received M/F (4.1 h; P=0.017). The number of surgeons satisfied with the level of sedation/analgesia provided by D/F was significantly higher than for M/F (P=0.001). Therefore, dexmedetomidine/fentanyl appears to provide better sedation, stable haemodynamics, surgeon satisfaction, and postoperative analgesia than midazolam/fentanyl during office-based unilateral impacted tooth extraction. PMID:24794760
Yu, C; Li, S; Deng, F; Yao, Y; Qian, L
Oral infections have been implicated in adverse pregnancy outcomes such as pre-eclampsia, premature delivery and growth retardation. A 28-year-old and 9 months pregnant otherwise healthy woman with a complaint of facial swelling and dental pain was referred to the Department of Oral and Maxillofacial Surgery. Oral examination revealed perimandibular and masticator space infection related to the left mandibular third molar tooth. Eight hours after surgical intervention, fetal distress developed. The patient was immediately taken into surgery and a male baby delivered by Caesarean section. The baby was then admitted to the intensive care unit. On the twelfth day of his admission, the baby was discharged in good health. Severe maxillofacial infection in pregnancy is a medically complicated situation which should be treated by an oral and maxillofacial surgeon in consultation with an obstetric and gynaecology service. PMID:23441802
Çelebi, N; Kütük, M S; Ta?, M; Soylu, E; Etöz, O A; Alkan, A
Objective. This preclinical pilot study evaluated the systemic, radiographic, and histological responses to bone putty containing lidocaine in a canine tooth extraction model. Methods. In five beagle dogs the right mandibular premolars were extracted and sockets grafted with (1) xenograft particulate bone and a collagen sponge plug (control), (2) bone putty alone, (3) bone putty mixed with xenograft (3?:?1), or (4) xenograft sandwiched between bone putty. At 6 weeks post-op, the syste...
Eric Everett; Salvador Nares; Ricardo Padilla; David Paquette; Antonio Moretti; Akshay Kumarswamy
The recovery of DNA from teeth is usually associated with the destruction of the evidential tooth using, for instance a special grinding mill. In some cases, however, a minimal invasive method of DNA retrieval with a high recovery is required particularly when historical material has to be investigated. A tooth attributed to the German Emperor Wilhelm II was the only source of DNA in an analysis of a possible paternity and the DNA had to be extracted without destroying the appearance of the tooth. Here, the results of the DNA analysis are presented. PMID:12690510
Pfeiffer, H; Benthaus, S; Rolf, B; Brinkmann, B
The X radiation effects on the wound healing process after teeth extractions are studied histologically. Albino rats are employed. After their right upper incisors were extracted, they were divided into groups of 20 animals each. With exception of the group I (control), 24 hours after teeth extractions the groups II, III and IV received X radiation, respectively, in the dosage of 75,125 and 175 R. The rats were sacrificed in group of 4, at 3, 6, 9,15 and 21 postoperative days and a histological study is done. (M.A.C.)
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
Proteolytic activity of viscera extract from hybrid catfish (Clarias macrocephalus × Clarias gariepinus) was studied. The optimal pH and temperature were 9.0 and 50°C, respectively, when toothed ponyfish (Gazza minuta) muscle was used as a substrate. When viscera extract from hybrid catfish was used for the production of protein hydrolysate from toothed ponyfish muscle, extract concentration, reaction time, and fish muscle/buffer ratio affected the hydrolysis and nitrogen recovery (NR) (p<0.05). Optimum conditions for toothed ponyfish muscle hydrolysis were 3.5% hybrid catfish viscera extract, 15 min reaction time and fish muscle/buffer ratio of 1:3 (w/v). High correlation between the degree of hydrolysis (DH) and NR (R(2)=0.974) was observed. Freeze-dried hydrolysate had a high protein content (89.02%, dry weight basis) and it was brownish yellow in colour (L(?)=63.67, a(?)=6.33, b(?)=22.41). The protein hydrolysate contained a high amount of essential amino acids (48.22%) and had arginine and lysine as the dominant amino acids. PMID:23122156
Klomklao, Sappasith; Kishimura, Hideki; Benjakul, Soottawat
Introduction. Dental treatment performed in patients receiving continuous oral anticoagulant drug therapy is becoming increasingly common in dental offices. For these patients it is imperative to carry out careful anamnesis, as well as a multiprofessional clinical evaluation with regard to the risk and control of hemorrhagic or thromboembolic episodes. Objectives and Material and Methods. The aim is to evaluate postextraction hemorrhagic or thromboembolic episodes in patients who have been on anticoagulant medications for an uninterrupted period of 48 months. Results. Among the 108 patients evaluated, 215 extractions were performed in which there was only one case of postoperative bleeding. Warfarin was used by 98 patients; Warfarin associated with salicylic acetic acid by 9 patients and salicylic acetic acid in only 1 patient. As regards the serologic tests performed, International Normalized Ratio (INR) ranged from 0.8 to 4.9, with a mean of 3.15. Conclusion. Extractions in patients on oral anticoagulants must be performed in the least traumatic manner possible. It is not necessary to stop anticoagulant therapy to perform extractions. Local hemostasis techniques, such as obliterative sutures alone are sufficient to prevent hemorrhagic complications. PMID:21991458
Pereira, Claudio Maranhão; Gasparetto, Patrícia Freire; Carneiro, Danilo Santos; Corrêa, Maria Elvira P.; Souza, Cármino Antônio
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 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)
Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish 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
Mario, Castañeda Deroncelé.
Sixty percent of implant-supported dental prostheses require bone grafting to enhance bone quantity and quality prior to implant placement. We have developed a metallic magnesium particle/PLGA composite scaffold to overcome the limitations of currently used dental bone grafting materials. This is the first report of porous metallic magnesium/PLGA scaffolds synthesized using a solvent casting, salt leaching method. We found that incorporation of varying amounts of magnesium into the PLGA scaffolds increased the compressive strength and modulus, as well as provided a porous structure suitable for cell infiltration, as measured by mercury intrusion porosimetry. Additionally, combining basic-degrading magnesium with acidic-degrading PLGA led to an overall pH buffering effect and long-term release of magnesium over the course of a 10-week degradation assay, as measured with inductively coupled plasma-atomic emission spectroscopy. Using an indirect proliferation assay adapted from ISO 10993:5, it was found that extracts of medium from degrading magnesium/PLGA scaffolds increased bone marrow stromal cell proliferation in vitro, a phenomenon observed by other groups investigating magnesium's impact on cells. Finally, magnesium/PLGA scaffold biocompatibility was assessed in a canine socket preservation model. Micro-computed tomography and histological analysis showed the magnesium/PLGA scaffolds to be safer and more effective at preserving bone height than empty controls. Three-dimensional magnesium/PLGA composite scaffolds show promise for dental socket preservation and also, potentially, orthopedic bone regeneration. These scaffolds could decrease inflammation observed with clinically used PLGA devices, as well as enhance osteogenesis, as observed with previously studied magnesium devices. PMID:25234156
Brown, Andrew; Zaky, Samer; Ray, Herbert; Sfeir, Charles
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 be...
This article describes an esthetic alternative for the periodontally compromised dentition. It involves a technique for using a natural tooth pontic (bonded with resin composite and reinforced by an intracoronal orthodontic wire), for replacing an anterior tooth in a periodontally compromised, mobile dentition. Following extraction and root resection of the maxillary central incisor, recess grooves were placed into the pontic and the adjacent abutment teeth. Intracoronal round orthodontic wire (0.032) was embedded into these preparations and bonded with acid-composite, which increases the retention of the tooth pontic. PMID:9515414
Breault, L G; Manga, R K; Elliston, N K
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.
Klinger de Souza, Amorim; Lucas Celestino Guerzet, Ayres; Rafael Soares da, Cunha; Liane Maciel de Almeida, Souza; Mônica Silveira, Paixao; Francisco, Groppo.
... 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 ...
Purpose: The aim of present investigation was to evaluate marginal bone level after 5-year follow-up of implants placed in healed ridges and fresh extraction sockets in maxilla with immediate loading protocol. Materials and Methods: Thirty-six patients in need of a single-tooth replacement in the anterior maxilla received 42 Astra Tech implants (Astra Tech Implant system™, Dentsply Implants, Mölndal, Sweden). Implants were placed either in healed ridges (group I) or immediately into fresh extraction sockets (group II). Implants were restored and placed into functional loading immediately by using a prefabricated abutment. Marginal bone level relative to the implant reference point was recorded at implant placement, crown cementation, 12, 36, and 60 months following loading using intra-oral radiographs. Measurements were made on the mesial and distal sides of each implant. Results: Overall, two implants were lost from the group II, before final crown cementation: they were excluded from the study. The mean change in marginal bone loss (MBL) after implant placement was 0.26 ± 0.161 mm for 1 year, and 0.26 ± 0.171 mm for 3 years, and 0.21 ± 0.185 mm for 5 years in extraction sockets and was 0.26 ± 0.176 mm for 1 year and 0.21 ± 0.175 mm for 3 years, and 0.19 ± 0.172 mm for 5 years in healed ridges group. Significant reduction of marginal bone was more pronounced in implants inserted in healed ridges (P < 0.041) compared to fresh surgical extraction sockets (P < 0.540). Significant MBL was observed on the mesial side of the implant after cementation of the provisional (P < 0.007) and after 12 months (P < 0.034) compared to the distal side which remained stable for 3 and 5 years observation period. Conclusions: Within the limitations of this study, responses of local bone to immediately loaded implants placed either in extraction sockets or healed ridges were similar. Functional loading technique by using prefabricated abutment placed during the surgery time seems to maintain marginal bone around implant in both healed and fresh extraction sites. PMID:24550840
Berberi, Antoine N.; Sabbagh, Joseph M.; Aboushelib, Moustafa N.; Noujeim, Ziad F.; Salameh, Ziad A.
Objective: To evaluate the criteria for the prescription of oral bisphosphonates (OB) in a series of women with osteoporosis referred for tooth extraction. Study design: The study included 38 postmenopausal women on treatment with OBs. The following variables were analysed: age, weight, height, type of OB and duration of treatment, bone densitometry and risk factors for osteoporosis. In addition, the osteoporosis self-assessment tool (OST) was administered and collagen type I C-telopeptide (CTX) levels were measured. Results: Bone densitometry had only been performed in six patients (15.7%) before starting OB treatment. Based on the results of the OST, nine (23.6%) of the participants presented a low risk of osteoporosis. CTX levels were measured in 23 patients: 11 (47.8%) presented values below 150 pg/ml. Conclusion: Although all patients in the present series were on treatment with OBs, a large percentage did not satisfy the criteria for the initiation of treatment for postmenopausal osteoporosis. Key words:Osteoporosis, oral bisphosphonates, osteonecrosis of the jaws. PMID:22322496
Fernández-Feijoo, Javier; Fernández-Montenegro, Paula; González-Mosquera, Antonio; Vázquez-García, Emma; Diz-Dios, Pedro
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.
Schropp, Lars; Wenzel, Ann
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
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.
Rodrigo Mathias Freire de Menezes, Carneiro; Rafael Soares da, Cunha; Liane Maciel de Almeida, Souza; Francisco, Groppo.
Case report of an accidentally diagnosed supernumerary tooth in the superior orbital fissure. Computed tomography (CT) contributed with a more precise localization of the tooth being situated between the orbit and the brain. CT also showed that there was no cyst or other pathological process around the supernumerary tooth, which is plausible and frequently reported in the literature.
Sjoeberg, S.; Loerinc, P.
Case report of an accidentally diagnosed supernumerary tooth in the superior orbital fissure. Computed tomography (CT) contributed with a more precise localization of the tooth being situated between the orbit and the brain. CT also showed that there was no cyst or other pathological process around the supernumerary tooth, which is plausible and frequently reported in the literature. (orig.)
With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has devel...
Kim, Young-kyun; Lee, Junho; Um, In-woong; Kim, Kyung-wook; Murata, Masaru; Akazawa, Toshiyuki; Mitsugi, Masaharu
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.
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
Boonyagul, Sani; Banlunara, Wijit; Sangvanich, Polkit; Thunyakitpisal, Pasutha
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.
Background Wisdom teeth are usually removed as a routine procedure for therapeutic or prophylactic reasons. Developing wisdom teeth are easy accessible source of stem cells during the adulthood which could be obtained. Methods Search of the PubMed for stem cells and tooth was done. An inclusion criterion was extract of stem cells from wisdom tooth. Results Stem cells can be obtained from dental papilla, dental sac, periodontal membrane and dental follicle of wisdom tooth....
Ectopic tooth is not uncommon and usually occurs in the palate and maxillary sinus. We report a case of ectopic tooth located in the nasal cavity, a rare site. The mass depicted by CT was highly attenuated, and central lucency was observed
Ectopic tooth is not uncommon and usually occurs in the palate and maxillary sinus. We report a case of ectopic tooth located in the nasal cavity, a rare site. The mass depicted by CT was highly attenuated, and central lucency was observed.
Park, Si Hyun; Kim, Ji Hye; Hwang, Hee Young; Yang, Dal Mo; Kim, Hyung Sik; Park, Chol Heui [Gachon Medical School, Inchon (Korea, Republic of)
Loss of anterior tooth impairs patients physically and emotionally as well as presents a challenge for dentists. This article presented a method of replacing one anterior tooth that was extracted because of periodontitis. The proposed method involves the use of the natural crown as pontic with fiber-reinforced composite resin-bonded fixed partial denture. PMID:24437304
Xu, Mengrong; Zhang, Qian; Qiu, Haiyan
Full Text Available An integrated single-tooth modeling scheme is proposed for the 3D dental model acquired by optical digitizers. The cores of the modeling scheme are fusion regions extraction, single tooth shape restoration, and single tooth separation. According to the “valley” shape-like characters of the fusion regions between two adjoining teeth, the regions of the 3D dental model are analyzed and classified based on the minimum curvatures of the surface. The single tooth shape is restored according to the bioinformation along the hole boundary, which is generated after the fusion region being removed. By using the extracted boundary from the blending regions between the teeth and soft tissues as reference, the teeth can be separated from the 3D dental model one by one correctly. Experimental results show that the proposed method can achieve satisfying modeling results with high-degree approximation of the real tooth and meet the requirements of clinical oral medicine.
Coronal fractures of the anterior teeth are a common form of dental trauma and its sequelae may impair the establishment and accomplishment of an adequate treatment plan. Among the various treatment options, reattachment of a crown fragment is a conservative treatment that should be considered for crown fractures of anterior teeth. This clinical case reports the management of two coronal tooth fracture cases that were successfully treated using tooth fragment reattachment using glass-fibre-reinforced composite post. PMID:23853012
Maitin, Nitin; Maitin, Shipra Nangalia; Rastogi, Khushboo; Bhushan, Rajarshi
Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is ...
Extracted teeth can be bonded directly to adjacent teeth utilizing a prefabricated composite resin framework reinforced with polyethylene fiber as a noninvasive long-term provisional tooth replacement. This immediate provisional restoration allow for exact repositioning of the coronal part of the extracted tooth in its original intraoral three-dimensional position and thus relieves the apprehension of the patient caused by the sudden loss of an anterior tooth.
Bhargava, Smriti; Namdev, Ritu; Dutta, Samir; Tiwari, Rajkumar
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 synthetic polymers, three-dimensional scaffold fabrication, stem cell transplantation, and stem cell homing. A tooth is a complex biological organ. Tooth loss represents the most common organ failure. Tooth regeneration encompasses not only regrowth of an entire tooth as an organ, but also biological restoration of individual components of the tooth including enamel, dentin, cementum, or dental pulp. Regeneration of tooth root represents perhaps more near-term opportunities than the regeneration of the whole tooth. In the adult, a tooth owes its biological vitality, arguably more, to the root than the crown. Biomaterials are indispensible for the regeneration of tooth root, tooth crown, dental pulp, or an entire tooth. PMID:21699433
Yuan, Zhenglin; Nie, Hemin; Wang, Shuang; Lee, Chang Hun; Li, Ang; Fu, Susan Y.; Zhou, Hong
Full Text Available Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is likely to revolutionize dental health and well-being of people by regenerating teeth over the next decade.
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 newly identified factors involved in endocrine regulation of vitamin D, phosphate, and calcium, including phosphate-regulating endopeptidase homolog, X-linked, fibroblast growth factor 23, and dentin matrix protein 1. Systemic mineral metabolism intersects with local regulation of mineralization, and factors including tissue nonspecific alkaline phosphatase are necessary for proper mineralization, where rickets can result from loss of activity of tissue nonspecific alkaline phosphatase. Individuals suffering from rickets often bear the additional burden of a defective dentition, and transgenic mouse models have aided in understanding the nature and mechanisms involved in tooth defects, which may or may not parallel rachitic bone defects. This report reviews dental effects of the range of rachitic disorders, including discussion of etiologies of hereditary forms of rickets, a survey of resulting bone and tooth mineralization disorders, and a discussion of mechanisms, known and hypothesized, involved in the observed dental pathologies. Descriptions of human pathology are augmented by analysis of transgenic mouse models, and new interpretations are brought to bear on questions of how teeth are affected under conditions of rickets. In short, the rachitic tooth will be revealed. PMID:23939820
Foster, Brian L; Nociti, Francisco H; Somerman, Martha J
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.
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 inferi...
Karatza Ageliki A; Danias Peter G; Davlouros Periklis A; Kiaffas Maria G; Alexopoulos Dimitrios
Replacement resorption rate is a variable process, and is dependent on age, basal metabolic rate, extra-alveolar time, treatment prior to replantation, amount of root dentin, severity of trauma, and extent of periodontal ligament necrosis. In patients 7-16 years old a tooth is lost 3-7 years after the onset of root resorption. The complications that may develop as a consequence of ankylosis of a permanent incisor in children are due to the inevitable early loss of the traumatized tooth and local arrest of alveolar bone development. An ankylosed tooth should be removed before the changes become so pronounced that they compromise future prosthetic treatment. The treatment options may involve: interceptive regenerative treatment, early extraction of the ankylosed tooth, orthodontic space closure, intentional replantation, extraction of the ankylosed tooth followed with immediate ridge augmentation/preservation, auto-transplantation, single tooth dento-osseous osteotomy, and decoronation. The purpose of this article was to review the considerations involved in the decision-making concerning the use of the decoronation technique for the treatment of a permanent incisor diagnosed as ankylosed. PMID:18173685
Sapir, Shabtai; Shapira, Joseph
A complication of endodontic treatment is over-preparation of the tooth structure in an attempt to access calcified pulp chambers and root canals. This could result in thin root walls that might compromise the long-term prognosis of the tooth. There are various treatment options when such a complication occurs, among them, extraction of the compromised tooth and its replacement with a dental implant. This clinical report describes a nonsurgical, multidisciplinary treatment alternative where a maxillary anterior tooth with a thinned root wall was successfully saved by repairing the damaged root to its original thickness using a composite resin material and subsequently restoring with a cast post and core and a crown. PMID:24654367
Comut, Alper; Foran, Denise; Cunningham, Ralph P
Full Text Available Aim: The aim of this study was to analyze by histomorphometric parameters the use of acellular dermal matrix (ADM with or without anorganic bovine bone matrix (ABM / synthetic cell-binding peptide P-15 in the formation of bone in human alveoli. Materials and methods: Eighteen patients in need of extraction of maxillary anterior teeth were selected and randomly assigned to the test group (ADM plus ABM/P-15 or the control group (ADM only. Histomorphometric measurements and histological analysis were recorded about 6 months after ridge preservation procedures in ten patients. The amount of newly formed bone, the most recently formed bone, fibrous tissue plus marrow spaces and remaining graft particles were measured and analyzed. Results: At 6 months, the new bone area parameter and the percentage of fibrous tissue plus marrow space areas showed higher values to the control group, and statistically significant differences when compared with the test group (p=0.03. Conclusion: The ADM acted as a membrane. The association of ABM/P-15 with ADM resulted in new bone formation within the alveoli, but the results were not considered relevant when used in this indication.
Arthur B. Novaes Jr
Pathologic tooth migration (PTM) is a common complication of moderate to severe periodontitis and is often the motivation for patients to seek periodontal therapy. In this review of the literature, available information concerning prevalence, etiology, treatment, and prevention of pathologic tooth migration is summarized. Prevalence of PTM among periodontal patients has been reported to range from 30.03% to 55.8%. A survey of the literature regarding chief complaints of periodontal patients support these high prevalence findings. The etiology of PTM appears to be multifactorial. Periodontal bone loss appears to be a major factor in the etiology of PTM. Many aspects of occlusion can contribute to abnormal migration of teeth, and more than one of those factors may be present in an individual patient. Soft tissue forces of the tongue, cheeks, and lips are known to cause tooth movement and in some situations can cause PTM. Also considered important in the etiology of PTM is pressure produced from inflammatory tissues within periodontal pockets. Because extrusion is a common form of PTM, clinical observations support the theory that eruption forces sometimes play a role in the etiology of PTM. Many oral habits have been associated with PTM which are often difficult for the therapist to detect. Most cases of severe PTM require a team approach to achieve success. Periodontal, orthodontic, and prosthodontic treatment are often required. Many patient variables enter into the selection of treatment for PTM. In early stages of PTM, spontaneous correction of migrated teeth sometimes occurs after periodontal therapy. Light intrusive forces are used successfully to treat extrusion and flaring forms of PTM. Based on the literature reviewed, it appears that many cases of PTM could be prevented through the early diagnosis and treatment of periodontal disease, occlusal contributing factors, gingival enlargement, and oral habits. PMID:15948679
Brunsvold, Michael A
Processo de reparo em feridas de extração dentária em camundongos tratados com o complexo Symphytum officinale e Calendula officinallis / Process of repair in tooth extraction sores in treated mice with Symphytum officinale and Calendula officinallis compound
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Medicamentos homeopáticos como o Symphytum officinalle e a Calendula officinallis são dotados de propriedades anti-sépticas, antiinflamatória, cicatrizantes e também agem como promotores da consolidação de fraturas ósseas. Neste trabalho, uniram-se esses dois medicamentos similares em um complexo pa [...] ra verificar o seu efeito no reparo em feridas de extração dentária em camundongos. O complexo Symphytum officinalle e Calendula officinallis nas potências de 6CH e 3CH, respectivamente, foi ministrado por via oral ao grupo tratado durante 5 dias antes e após a extração do incisivo superior direito. No grupo controle, administraram-se 5ml de álcool etílico a 70% diluídos em 30 ml de soro fisiológico. Após a proservação, os animais foram sacrificados, a maxila direita separada da esquerda, fixada e processada para inclusão em parafina. Após a microtomia, os cortes obtidos foram corados pela H/E. A análise histológica mostrou que, tanto no grupo controle como no tratado, o alvéolo dentário estava preenchido por tecido de granulação e tecido ósseo neoformado, com graus variáveis de maturação, rico em osteócitos. No entanto, nos animais tratados, o processo de reparo em feridas após extração dentária do incisivo superior direito mostrou um avanço progressivo de neoformação óssea mais acentuado quando comparado ao grupo controle, em tempos equivalentes. Estes resultados enfatizam as propriedades biológicas do complexo Symphytum officinalle e Calendula officinallis e sua possível utilização como recurso terapêutico na Odontologia. Abstract in english Homeopathic medicines as Symphytum officinale and Calendula officinallis are endowed with antiseptic, antiphlogistic and cicatrizant properties and promoter of the consolidation of bone fracture. This research combined these two similar medicines in a compound to examine its action in the repair of [...] tooth extraction sores in mice. The compound Symphytum offic. and Calendula offic. at the respective potencys of 6CH and 3CH was orally administered to the treated group during 5 days before and after the extraction of the rigth upper incisor. To the control group were administered 5 ml of ethylic alchol 70% diluted in 30 ml of physiologic serum. After a period of expectation, the animals were sacrificed, the right maxila was separated of the left maxila, this was fixed and the laboratories techniques were realized for inclusion in paraffin. After that, the piece was cut in the microtome, and the laminas were dyed by H/E. The analysis showed that the control and treated group exhibited the dental alveolus fulfilled with granulation tissue and neoformed bone tissue with variable degrees of maturation, abundant in osteocites. However, at the treated animal the healing process of the sore after the extraction of the rigth upper incisor showed a bone neoformation very pronounced when compared with the control group at equivalent times. Those results showed the biological properties of the compound Symphytum offic. and Calendula offic. and its utilization as a therapeutical help in Odontology.
Eleny, BALDUCCI-ROSLINDO; Karina Gonzales, SILVÉRIO; Daniela Mercaldi, MALAGOLI.
The objectives of this analysis were to describe the numbers of teeth lost and those indicated for extraction, dental prosthetic status, and occluding tooth pairs among adults in Southern China and to investigate factors affecting tooth mortality. A sample consisting of 1573 35- to 44-year-old and 1515 65- to 74-year-old urban and rural Chinese was examined clinically by calibrated examiners. Teeth not present for any reason were defined as missing (MT). The sum of MT and teeth indicated for ...
Lin, Hc; Corbet, Ef; Lo, Ecm; Zhang, Hg
Background: The importance of tooth sectioningis realized in disasters such as earthquake, airplanecrash investigation, terror, micro leakage studies, ageestimation etc. The objective of this study was to developa simple method to make thin sections (approximately100 mm) from freshly extracted teeth.Methods: One hundred and twenty human premolarsrecently extracted for orthodontic purpose were used forthis study. The teeth were stored in 0.5% chorlaraminefor 2 weeks and were not allowed to dry...
Muneer Gohar Babar; Ma Angela Gonzalez
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...
Yuan, Zhenglin; Nie, Hemin; Wang, Shuang; Lee, Chang Hun; Li, Ang; Fu, Susan Y.; Zhou, Hong; Chen, Lili; Mao, Jeremy J.
Tooth development results from sequential and reciprocal interactions between the oral epithelium and the underlying neural crest-derived mesenchyme. The generation of dental structures and/or entire teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin and enamel. Although mesenchymal stem cells from different origins have been extensively studie...
Bluteau, G.; H-u, Luder; Bari, C.; Ta, Mitsiadis
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
Full Text Available SciELO Chile | Language: Spanish Abstract in spanish 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®.
Ximena, Moreno Ruiz; Carmen Gloria, Narváez Carrasco; Verónica, Bittner Schmidt.
Full Text Available Objective: To survey the sociocultural profile of a specific group of individuals who donated teeth to the Human Tooth Bank of Positivo University, Curitiba, Paraná, Brazil. Methods: The research consisted of a questionnaire containing the following information about: Patient’s age, sex, occupation, education, reason for tooth loss and intention to replace the missing tooth by means of prosthesis or implant. The questionnaire was filled out by 50 patients after having the extraction procedure performed and donating the dental organ. The data were compiled and analyzed by means of descriptive and multivariate statistics. Results: The sociocultural profile of the donor was basically composed of individuals in the age group between 30 and 50 years, with educational level ranging from zero to nine or more years of formal schooling. Caries disease was the most frequent reason for tooth loss (36%, followed by periodontal disease (34%. Of the donors analyzed, more than half did not intend to replace the tooth. Furthermore, according to the multivariate analysis, the most relevant factors for assessing the profile of donors were the variables age, orthodontic indication, caries and periodontal disease. Conclusion: This information was shown to be relevant for structuring the oral health care services, as well as in the strategy for obtaining teeth from the Public Health Units.
Mariane Moreira Poletto
Full Text Available A cross-sectional study was carried out to analyze tooth loss resulting from caries in relation to the number of times the extracted tooth had been restored, the type of caries diagnosed (primary or secondary, and socioeconomic indicators of patients from the city of Recife, Brazil. Ten public health centres and ten centres associated with health insurance companies were randomly selected. The size of the sample was calculated using a standard error of 2.5%. A confidence interval of 95% and a 50% prevalence of reasons for extractions were used for calculating the sample. The minimum size of the sample for meeting these requirements was 381 patients. Patients were randomly selected from the list of adults registered at each centre. A total of 410 patients were invited to take part in the study. The response rate was 100%, but 6 patients were excluded due to incompleteness of data in the questionnaire applied. An assessment was made to obtain the number of decayed, missing or filled teeth (DMFT index and the reasons for extraction. The results showed a highly significant (p < 0.001 relationship between the number of times the tooth indicated for extraction had been restored and the reason for extraction being caries. Furthermore, the majority of teeth extracted due to caries had been restored two or more times. A highly statistically significant association was also observed between one indicator of use of dental services (F/DMFT and extraction due to caries (p < 0.001. The findings questioned the belief that tooth loss can be prevented in the general population by merely providing restorative treatment.
Caldas Junior Arnaldo de França
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
Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish 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
José Raúl, Blanco; Felix Alejandro, Mejía; Luis Felipe, Restrepo.
We report the measurements of ablation threshold of human tooth in air using photo-thermal deflection technique. A third harmonic (355nm) of Nd:YAG (yttrium aluminum garnet) laser was used for irradiation and a low power helium neon laser as a probe beam. The experimental observations of ablation threshold in conjunction with theoretical model based on heat conduction equations for simulating the interaction of a laser radiation with a calcified tissue are used to estimate the absorption coefficient of human tooth.
Franklin, Sushmita R.; Chauhan, P.; Mitra, A.; Thareja, R. K.
Tooth loss compromises human oral health. Although several prosthetic methods, such as artificial denture and dental implants, are clinical therapies to tooth loss problems, they are thought to have safety and usage time issues. Recently, tooth tissue engineering has attracted more and more attention. Stem cell based tissue engineering is thought to be a promising way to replace the missing tooth. Mesenchymal stem cells (MSCs) are multipotent stem cells which can differentiate into a variety ...
Peng, Li; Ye, Ling; Zhou, Xue-dong
Full Text Available Introduction: Fusion is a developmental anomaly in which two tooth buds are interconnected. In fusion, teeth are joined by dentine in their developmental stage. Fusion could be between normal teeth or between a normal and a supernumerary tooth. Fusion of the posterior teeth and supernumerary ones are rare.Case Report: A 26 year old woman was referred for extraction of semi impacted third molar. Panoramic radiographs were requested for the patient. In dental radiographs, a supernumerary tooth in distal region of the third molar was observed. Teeth looked like fused teeth. After obtaining consent from the patient, teeth were removed by surgical excision.
Jamileh Beygom Taheri
The aim of this manuscript was to discuss some important considerations about tooth fragment reattachment and report the success of a clinical case in which a tooth fragment and direct composite resin were used to restore a fractured anterior tooth. Clinical and radiographic examination 12 months after trauma showed good esthetics and periodontal health. PMID:22770482
Lise, D P; Vieira, L C Cardoso; Araújo, É; Lopes, G C
Full Text Available Tooth development results from sequential and reciprocal interactions between the oral epithelium and the underlying neural crest-derived mesenchyme. The generation of dental structures and/or entire teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin and enamel. Although mesenchymal stem cells from different origins have been extensively studied in their capacity to form dentin in vitro, information is not yet available concerning the use of epithelial stem cells. The odontogenic potential resides in the oral epithelium and thus epithelial stem cells are necessary for both the initiation of tooth formation and enamel matrix production. This review focuses on the different sources of stem cells that have been used for making teeth in vitro and their relative efficiency. Embryonic, post-natal or even adult stem cells were assessed and proved to possess an enormous regenerative potential, but their application in dental practice is still problematic and limited due to various parameters that are not yet under control such as the high risk of rejection, cell behaviour, long tooth eruption period, appropriate crown morphology and suitable colour. Nevertheless, the development of biological approaches for dental reconstruction using stem cells is promising and remains one of the greatest challenges in the dental field for the years to come.
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.
Burke, F M
Teeth move through alveolar bone, whether through the normal process of tooth eruption or by strains generated by orthodontic appliances. Both eruption and orthodontics accomplish this feat through similar fundamental biological processes, osteoclastogenesis and osteogenesis, but there are differences that make their mechanisms unique. A better appreciation of the molecular and cellular events that regulate osteoclastogenesis and osteogenesis in eruption and orthodontics is not only central t...
Wise, G. E.; King, G. J.
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.
Reilly, Mary M
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.
Slangen, Pierre; Corn, Stephane; Fages, Michel; Raynal, Jacques; Cuisinier, Frederic J. G.
The prevalence and severity of tooth wear is increasing in industrialised nations. Yet, there is no high-level evidence to support or refute any therapeutic intervention. In the absence of such evidence, many currently prevailing management strategies for tooth wear may be failing in their duty of care to first and foremost improve the oral health of patients with this disease. This paper promotes biologically sound approaches to the management of tooth wear on the basis of current best evide...
Kelleher, Martin G. D.; Bomfim, Deborah I.; Austin, Rupert S.
Despite advances in the knowledge of tooth morphogenesis and differentiation, relatively little is known about the aetiology and molecular mechanisms underlying supernumerary tooth formation. A small number of supernumerary teeth may be a common developmental dental anomaly, while multiple supernumerary teeth usually have a genetic component and they are sometimes thought to represent a partial third dentition in humans. Mice, which are commonly used for studying tooth development, only exhib...
Wang, Xiu-ping; Fan, Jiabing
...2010-04-01 2010-04-01 false Tooth shade resin material. 872.3690 Section 872.3690...Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of...
Esthesioneuroblastoma, also called olfactory neuroblastoma, is a rare malignant tumor originating in the olfactory epithelium in the upper nasal cavity with intracranial extension and may also be associated with secondary sinus diseases. Esthesioneuroblastoma has been observed to cause death by distant metastasis or by invasion through the cribriform plate and secondary meningitis. It usually produces nasal obstruction, epistaxis and less commonly anosmia, headache and pain. We report a case of esthesioneuroblastoma in a 50-year-old female who reported with tooth pain as a presenting symptom. PMID:25364164
Devi, Parvathi; Bhavle, Radhika; Aggarwal, Avanti; Walia, Cherry
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.
Pavlenko, A; Mironova-Ulmane, N; Polakov, M; Riekstina, D [Institute of Solid State Physics, University of Latvia, Riga (Latvia)
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
The organization and renewal capacity of teeth vary greatly among vertebrates. Mammals have only one row of teeth that are renewed at most once, whereas many nonmammalian species have multirowed dentitions and show remarkable capacity to replace their teeth throughout life. Although knowledge on the genetic basis of tooth morphogenesis has increased exponentially over the past 20 years, little is known about the molecular mechanisms controlling sequential initiation of multiple tooth rows or restricting tooth development to one row in mammals. Mouse genetics has revealed a pivotal role for the transcription factor Osr2 in this process. Loss of Osr2 caused expansion of the expression domain of Bmp4, a well-known activator of tooth development, leading to the induction of supernumerary teeth in a manner resembling the initiation of a second tooth row in nonmammalian species.
Marja L. Mikkola (University of Helsinki;Institute of Biotechnology REV)
Compared with conventional films digital radiography allows a wide range of exposure and scanner settings. The aim of this study was to investigate the diagnostic accuracy of the evaluation of tooth fractures depending on variations of exposure dose, scanner settings and surrounding tissues. Extracted human teeth were exposed separately and in a pig bone phantom before and after artificial fracture at 70 kV (Gendex Oralix DC) and three exposure settings using the Vistascan System I at three different resolution settings. Five dental observers evaluated 432 radiographs of 12 adequately fractured teeth under randomized conditions for the existence of a tooth fracture on a five-point scale. The highest value of true ratings (76.7%) with pig bone vicinity was achieved at 56 micro Gy (160 ms) and 20 lp mm(-1), followed by 71.7% at 27 micro Gy (80 ms) and 20 lp mm(-1). The worst diagnostic accuracy of 56.7% true ratings resulted from 6 micro Gy (20 ms) and 10 lp mm(-1). With radiographs of teeth in empty surroundings the rate of true decisions was in some cases significantly higher. For the diagnostics of tooth fractures with the Vistascan System I the diagnostic value seems to depend on, besides radiographic projection, the scanner resolution setting, the surrounding tissues and the exposure dose. PMID:18821958
Künzel, Andreas; Weimar, Sabine; Willers, Reinhart; Becker, Jürgen
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).
Full Text Available Following the introduction of the direct bonding of orthodontic brackets to enamel, numerous studies were designed to investigate the bonding characteristics of various adhesive systems. In these studies, different tooth types were used for testing including, incisors, premolars and molars. A confounding factor was related to the effect of using different tooth types on bond strength. The purpose of the present study was to compare the shear bond strength of orthodontic brackets to the enamel surface of various tooth types, while eliminating the influence of other extraneous variables such as differences in the adhesive system used and variation in the bracket base design. Sixty freshly extracted human teeth including 20 molars, 20 premolars, and 20 incisors were similarly prepared for bonding. The same orthodontic bonding system was used to bond the same type of metal brackets to all the teeth. The teeth were then stored in distilled water for 48 hours. An Instron Testing Machine was used to measure shear bond strength in Megapascals. The Analysis of Variance was used to compare the three groups. The comparisons of the shear bond strength for incisors (x=12.4+6.5 MPa, premolars (x=11.9+5.2 MPa and third molars (x=13.1+6.2 MPa indicted that they were not significantly different (p=0.84. In conclusion, the findings indicate that in vitro testing of bond strength is not significantly agecte.9y the use of various tooth types namely, incisors, premolars and molars. This finding suggests that investigators can use teeth that are more readily available e.g. third molars to test bond strength.
Tanzanian oral health services constitute mainly of tooth extractions. Consequently, individuals susceptible to dental caries and periodontal diseases will have a substantial number of missing teeth, which can affect oral function. The main objective of this study was to determine the consequences of tooth loss on the oral function and need for replacement of lost teeth among patients seeking treatment at the School of Dentistry MUHAS. During a period of three months, patients seeking dental ...
Quaker, Andrewleon S.
The submasseteric abscess is a serious problem related with the semi-impacted mandibular wisdom-tooth infection. Especially severe complications are long-term trismus and osteomyelitis of the mandibular ramus. Treatment must be radical and depends on the stage of the infection (acute or chronic, early or mature). Important remains the preventive extraction of the responsible third molar. PMID:2640669
Marti, K; Dimitroglou, D
Since the origin of tooth wear (attrition, abrasion and erosion) is multi-factorial, its diagnosis is complicated but vital. The so-called Tooth Wear Evaluation System, introduced earlier, makes a systematic diagnostic approach possible. The system consists of various modules, which can be used by the practitioner depending on the goal. Two new modules have been added to the Tooth Wear Evaluation System. The Therapy Start Module can be used to determine which one of the possible treatment modalities (counseling, monitoring, or restorative treatment) should be chosen. The Level of Difficulty Module gives the practitioner indications of the level of difficulty that may be encountered during a restorative treatment. PMID:23236739
Wetselaar, P; Kuijs, R H; van Pelt, A W J; van der Zaag, J; Roeters, F J M; Lobbezoo, F
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.
Dawson, Andreas; List, Thomas
Impaction of tooth is a situation in which an unerupted tooth is wedged against another tooth or teeth or otherwise located so that it cannot erupt normally. The supernumerary tooth is also called as hyperdontia and defined as the condition of having additional tooth to the regular number of teeth. The most common supernumerary tooth is a mesiodens, which is a mal-formed, peg-like tooth that occurs between the maxillary incisors. The supernumerary tooth is commonly impacted but they are frequently impacted on maxilla. Ectopic impaction of supernumerary tooth on mandibular condyle, coronoid process, ascending ramus, and pterygomandibular space is very rare condition. In this case, we report a case of impacted supernumerary tooth on mandibular sigmoid notch without definite pathologic change.
Impaction of tooth is a situation in which an unerupted tooth is wedged against another tooth or teeth or otherwise located so that it cannot erupt normally. The supernumerary tooth is also called as hyperdontia and defined as the condition of having additional tooth to the regular number of teeth. The most common supernumerary tooth is a mesiodens, which is a mal-formed, peg-like tooth that occurs between the maxillary incisors. The supernumerary tooth is commonly impacted but they are frequently impacted on maxilla. Ectopic impaction of supernumerary tooth on mandibular condyle, coronoid process, ascending ramus, and pterygomandibular space is very rare condition. In this case, we report a case of impacted supernumerary tooth on mandibular sigmoid notch without definite pathologic change.
Park, Won Se; Lee, Je Ho; Park, Hyok; Jung, Ho Gul; Kim, Kee Deog [Yonsei University College of Dentistry, Seoul (Korea, Republic of)
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.
McNamara, C M
In-office bleaching is an effective method for whitening teeth.Tooth sensitivity associated with in-office whitening is reversible and may range from mild to considerable. The incidence and severity of tooth sensitivity can be reduced by pretreatment with a desensitizer such as potassium nitrate. Histologic studies and clinical studies on long-term pulpal effects are lacking to definitively support the safety of in-office tooth whitening. Future studies on the etiology of tooth sensitivity related to whitening might greatly improve the means of preventing and managing this side effect. PMID:25513618
Kwon, So Ran; Swift, Edward J
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...
FARHEEN USTAD; MOHD INAYATULLAH KHAN; PRIYAYANKA BHUSHAN; FAREEDI MUKRAM ALI
Anthropologists have for many years considered human tooth wear a normal physiological phenomenon where teeth, although worn, remain functional throughout life. Wear was considered pathological only if pulpal exposure or premature tooth loss occurred. In addition, adaptive changes to the stomatognathic system in response to wear have been reported including continual eruption, the widening of the masticatory cycle, remodelling of the temporomandibular joint and the shortening of the dental ar...
Kaidonis, John A.
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 afte...
Landin, Maria A. Dos Santos Silva; Shabestari, Maziar; Babaie, Eshrat; Reseland, Janne E.; Osmundsen, Harald
Tooth wear has been recognised as a major problem in dentistry. Epidemiological studies have reported an increasing prevalence of tooth wear and general dental practitioners see a greater number of patients seeking treatment with worn dentition. Although the dental literature contains numerous publications related to management and rehabilitation of tooth wear of varying aetiologies, our understanding of the aetiology and pathogenesis of tooth wear is still limited. The wear behaviour of dental biomaterials has also been extensively researched to improve our understanding of the underlying mechanisms and for the development of restorative materials with good wear resistance. The complex nature of tooth wear indicates challenges for conducting in vitro and in vivo wear investigations and a clear correlation between in vitro and in vivo data has not been established. The objective was to critically review the peer reviewed English-language literature pertaining to prevalence and aetiology of tooth wear and wear investigations in dentistry identified through a Medline search engine combined with hand-searching of the relevant literature, covering the period between 1960 and 2011. PMID:21923888
Lee, A; He, L H; Lyons, K; Swain, M V
Full Text Available AIM: To investigate the prevalence of tooth transposition in a sample of Greek dental patients. STUDY DESIGN: Epidemiological study. TIME AND PLACE OF ACTION: Prefecture of Drama, time period 2001-2006. MATERIALS AND METHODS: The first author examined in her private practice 2034 consecutive patients seeking dental treatment. Patients with nationality other than Greek, individuals below 13 years of age with primary or mixed dentitions, patients without panoramic radiographs, patients with syndromes, as well as those who had more than one permanent tooth missing were excluded from the initial sample. In total, 1113 patients were assessed (288 men, 825 women with a mean age of 36.1 years (range: 13.1-73.0 years. MAIN MEASUREMENTS: Tooth transposition was investigated my means of clinical examination through observation and palpation, as well as with radiographic examination using panoramic radiographs. Results were analyzed with descriptive statistics. RESULTS: In total, only one case was found with tooth transposition presenting complete bilateral transposition between canine - lateral incisor in the maxilla. The percentage of patients with tooth transposition in the total dental population examined was 0.09%. The prevalence of this phenomenon in females was 0.12%, whereas in males it was 0%. Men / women ratio was found 0:1. CONCLUSIONS: Tooth transposition in Greek population is rather rare, it is most often encountered in females and concerns mostly maxillary canines and lateral incisors.
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.
Bertoncini, C. A.; Hinders, M. K.; Ghorayeb, S. R.
Full Text Available Background: The importance of tooth sectioningis realized in disasters such as earthquake, airplanecrash investigation, terror, micro leakage studies, ageestimation etc. The objective of this study was to developa simple method to make thin sections (approximately100 mm from freshly extracted teeth.Methods: One hundred and twenty human premolarsrecently extracted for orthodontic purpose were used forthis study. The teeth were stored in 0.5% chorlaraminefor 2 weeks and were not allowed to dry at any stageof the experiment. The teeth were thoroughly washedin distilled water teeth and then were sectionedbuccolingually from crown to the root portion.Results: A detailed embedding-cutting-mountingprocedure is described. The prepared thin groundsections were then examined under a Polarised lightmicroscope for the enamel and the dentine, as well asthe caries lesions can clearly be distinguished.Conclusion: This is an effective and efficient methodfor preparation of ground sections in which the hardtissue details are preserved.
Muneer Gohar Babar
Full Text Available Statement of Problem: Reduction of orthodontic therapy treatment time is considered an important goal inthe management of malocclusion in adult patients. Corticotomy- facilitated orthodontic treatment may beconsidered an intermediate therapy between orthognatic surgry and conventional orthodontics for reducing treatment time.Purpose: This study was undertaken to evaluate and compare the rate of tooth movement of upper canine following corticotomy with conventional method.Materials and Methods: Ten young adult patients, 17-25 years old was selected through sequential sampling procedure in orthodontics department of Shiraz Dental School. The patients exhibited different orthodontic problems and needed extraction of premolars. Following extraction of premolars and initial phase oforthodontic treatment, corticotomy were performed unilaterally on buccual and palatal sides of extraction areaas described by Takami. The other imoperated sides were used as control. After subsiding the resultant inflammation, the activated NiTi spring was used and measurement of the amount of tooth movement wereassessed by using Rugae as reference point. The panoramic radiographs were super imposed for evaluation of canines tipping. For analyzing the results, Kolmogorou- simirnov and t.tcst were used. Results: The rate of canine tooth movement was much greater in the corticotomy sides than the unoperated (control side (P=0.015. This was especially significant at the end of first week of tooth movement(P=0.000. Comparing the two sides, the amount of canine tipping was much lesser in corticotomy group than the control group (P=0.046. There was no significant difference concerning the anchorage loss between thetwo groups (P=0.410.Conclusion: Corticotomy procedure had a positive effect on the rate of tooth movement with less tipping of the canines comparing to conventional orthodontic treatment. To get more benefit from this procedure, it is recommended to select those patients who do not need canine alignment after premolars extraction, such asbimaxillary dento alveolar protrusions.
Histologic Healing Following Tooth Extraction With Ridge Preservation Using Mineralized Freeze Dried Bone Allograft Alone Versus a Combined Mineralized-Demineralized Freeze Dried Bone Allograft. A Randomized Controlled Clinical Trial.
Background: Mineralized and demineralized freeze-dried bone allografts (FDBA) are used in alveolar ridge preservation, however each material has advantages and disadvantages. Combinations of allografts aimed at capitalizing on the advantages each offers are available. To date there is no evidence to indicate if a combination allograft is superior in this application. The primary objective of this study is to histologically evaluate and compare healing of non-molar extraction sites grafted with either mineralized FDBA or a 70:30 mineralized: demineralized FDBA combination allograft in alveolar ridge preservation. The secondary objective is to compare dimensional changes in ridge height and width after grafting with these two materials. Materials: 42 patients randomized into two equal groups received ridge preservation with either 100% mineralized FDBA (active control group) or the combination 70% mineralized:30% demineralized allograft (test group). Sites were allowed to heal for 18-20 weeks, at which time core biopsies were obtained and dental implants were placed. Alveolar ridge dimensions were evaluated at the time of extraction and at implant placement, including change in ridge width and change in buccal and lingual ridge height. Histomorphometric analysis was performed to determine percentage of vital bone, residual graft, and connective tissue/other non-bone components. Results: There was no significant difference between groups in alveolar ridge dimensional changes. Combination allograft produced increased vital bone percentage, 36.16%, compared to the FDBA group, 24.69% (p=0.0116). The combination allograft also had a significantly lower mean percentage of residual graft particles at 18.24% compared to FDBA at 27.04% (p=0.0350). Conclusions: This study provides the first histologic evidence showing greater new bone formation with a combination mineralized/demineralized allograft compared to 100% mineralized FDBA in alveolar ridge preservation in humans. Combination allograft results in increased vital bone formation while providing similar dimensional stability of the alveolar ridge when compared to FDBA alone in alveolar ridge preservation. PMID:25415247
Borg, Tyler D; Mealey, Brian L
The present-day terminology and definitions of tooth wear are not unambiguous. For diagnosing tooth wear, however, it is essential that they are unambiguous. In this article a proposal is presented for a tooth wear evaluation system with simplified definitions. This system consists ofa number of modules and can be used for various aspects of the diagnostic procedure. It can be used for the quantification of tooth wear, both for periodic screening and for the monitoring of tooth wear in individual patients. The scoring of occlusal/incisal tooth wear as well as of non-occlusal/non-incisal tooth wear is possible. The evaluative system is also suitable for determining which type of tooth wear, such as attrition, abrasion and erosion, is most likely to have caused any observed loss of hard tooth tissue. PMID:21761796
Wetselaar, P; van der Zaag, J; Lobbezoo, F
Tooth wear is the non-carious loss of tooth tissue, which results from three processes namely attrition, erosion and abrasion. These can occur in isolation or simultaneously. Very mild tooth wear is a physiological effect of aging. This study aims to estimate the prevalence of tooth wear among 16-year old Malay school children and determine a feasible sample size for further study. Fifty-five subjects were examined clinically, followed by the completion of self-administered questionnaires. Questionnaires consisted of socio-demographic and associated variables for tooth wear obtained from the literature. The Smith and Knight tooth wear index was used to chart tooth wear. Other oral findings were recorded using the WHO criteria. A software programme was used to determine pathological tooth wear. About equal ratio of male to female were involved. It was found that 18.2% of subjects have no tooth wear, 63.6% had very mild tooth wear, 10.9% mild tooth wear, 5.5% moderate tooth wear and 1.8 % severe tooth wear. In conclusion 18.2% of subjects were deemed to have pathological tooth wear (mild, moderate & severe). Exploration with all associated variables gave a sample size ranging from 560 – 1715. The final sample size for further study greatly depends on available time and resources. PMID:22589636
Abd. Karim, Nama Bibi Saerah; Ismail, Noorliza Mastura; Naing, Lin; Ismail, Abdul Rashid
The most commonly prescribed cosmetic dental procedure is tooth whitening. Many manufacturers are involved in the development and sale of at-home tooth-whitening products that have been approved by the American Dental Association. However, the American Academy for Cosmetic Dentistry recommends dentist-supervised treatments. There are various causes for tooth discoloration and various formulas that can be compounded for tooth bleaching. Compounding pharmacists should increase their knowledge of the types and origins of tooth discoloration, bleaching techniques, and the advantages and disadvantages of tooth bleaching so that they can better serve their patients and be involved in this growing market. PMID:23974234
The evolution of tooth enamel microstructure in both extinct and extant mammalian groups has been extensively documented, but is poorly known in reptiles, including dinosaurs. Previous intensive sampling of dinosaur tooth enamel microstructure revealed that: (1) the three-dimensional arrangement of enamel types and features within a tooth-the schmelzmuster-is most useful in diagnosing dinosaur clades at or around the family level; (2) enamel microstructure complexity is correlated with tooth morphology complexity and not necessarily with phylogenetic position; and (3) there is a large amount of homoplasy within Theropoda but much less within Ornithischia. In this study, the examination of the enamel microstructure of 28 additional dinosaur taxa fills in taxonomic gaps of previous studies and reinforces the aforementioned conclusions. Additionally, these new specimens reveal that within clades such as Sauropodomorpha, Neotheropoda, and Euornithopoda, the more basal taxa have simpler enamel that is a precursor to the more complex enamel of more derived taxa and that schmelzmusters evolve in a stepwise fashion. In the particularly well-sampled clade of Euornithopoda, correlations between the evolution of dental and enamel characters could be drawn. The ancestral schmelzmuster for Genasauria remains ambiguous due to the dearth of basal ornithischian teeth available for study. These new specimens provide new insights into the evolution of tooth enamel microstructure in dinosaurs, emphasizing the importance of thorough sampling within broadly inclusive clades, especially among their more basal members. PMID:20518758
Hwang, Sunny H
Full Text Available "nBackground and Aims: Lasers with different characteristics have been used to stimulate orthodontic tooth movements and to inhibit the pain during tooth movements. Considering the contradictory finding in this respect, the effect of low level laser therapy (LLLT was evaluated on the pain during orthodontic tooth movement. "nMaterials and Methods: In this randomized clinical trial study, 12 patients were included with extracted upper first premolars and required canine retraction into extraction site. While in both sides canines were retracted by Niti coil spring, one side was exposed to GaAlAs laser (890nm. LLLT was done on the buccal and palatal mucosa by slow movement of probe. The patients were asked about their pain on both sides 2 days after beginning of retraction. Pain measurement was evaluated with VAS. "nResults: Pain perception in LLLT side significantly decreased (P=0.007. "nConclusion: Based on the results, single irradiation of GaAlAs laser (12J energy per tooth can decrease pain perception.
We report a 41-year-old woman with complex reflex epilepsy in which seizures were induced exclusively by the act of tooth brushing. All the attacks occurred with a specific sensation of sexual arousal and orgasm-like euphoria that were followed by a period of impairment of consciousness. Ictal EEG demonstrated two events of epileptic seizure that were provoked after tooth brushing for 38 and 14 seconds, respectively. The interictal EEG showed epileptiform discharges over the right anterior temporal region and interictal single photon emission computed tomography (SPECT) scan showed relative hypoperfusion in the uncus of right temporal lobe. Brain magnetic resonance imaging (MRI) revealed right hippocampal atrophy. We suggest that tooth-brushing epilepsy, especially with sexual ictal manifestations, may provide insight into the cerebral pathophysiology at the right temporolimbic structure. PMID:15010056
Chuang, Yao-Chung; Lin, Tsu-Kung; Lui, Chun-Chung; Chen, Shang-Der; Chang, Chen-Sheng
The accurate tooth partition of dental mesh is a crucial step in computer-aided orthodontics. However, tooth boundary identification is not a trivial task for tooth partition, since different shapes and their arrangements vary substantially among common clinical cases. Though curvature field is traditionally used for identifying boundaries, it is normally not reliable enough. Other methods may improve the accuracy, but require intensive user interaction. Motivated by state-of-the-art general interactive mesh segmentation methods, this paper proposes a novel tooth-target partition framework that employs harmonic fields to partition teeth accurately and effectively. In addition, a refining strategy is introduced to successfully segment teeth from the complicated dental model with indistinctive tooth boundaries on its lingual side surface, addressing an issue that had not been solved properly before. To utilise high-level information provided by the user, smart and intuitive user interfaces are also proposed with minimum interaction. In fact, most published interactive methods specifically designed for tooth partition are lacking efficient user interfaces. Extensive experiments and quantitative analyses show that our tooth partition method outperforms the state-of-the-art approaches in terms of accuracy, robustness and efficiency. PMID:25464355
Zou, Bei-Ji; Liu, Shi-Jian; Liao, Sheng-Hui; Ding, Xi; Liang, Ye
This study detected tooth-composite interfacial debonding during composite restoration by means of acoustic emission (AE) analysis and investigated the effects of composite properties and adhesives on AE characteristics. The polymerization shrinkage, peak shrinkage rate, flexural modulus, and shrinkage stress of a methacrylate-based universal hybrid, a flowable, and a silorane-based composite were measured. Class I cavities on 49 extracted premolars were restored with 1 of the 3 composites and 1 of the following adhesives: 2 etch-and-rinse adhesives, 2 self-etch adhesives, and an adhesive for the silorane-based composite. AE analysis was done for 2,000 sec during light-curing. The silorane-based composite exhibited the lowest shrinkage (rate), the longest time to peak shrinkage rate, the lowest shrinkage stress, and the fewest AE events. AE events were detected immediately after the beginning of light-curing in most composite-adhesive combinations, but not until 40 sec after light-curing began for the silorane-based composite. AE events were concentrated at the initial stage of curing in self-etch adhesives compared with etch-and-rinse adhesives. Reducing the shrinkage (rate) of composites resulted in reduced shrinkage stress and less debonding, as evidenced by fewer AE events. AE is an effective technique for monitoring, in real time, the debonding kinetics at the tooth-composite interface. PMID:23100273
Cho, N Y; Ferracane, J L; Lee, I B
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
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 statisticall
Carllini Barroso, Vicentini; Juliana Cama, Ramacciato; Rubens Gonçalves, Teixeira; Francisco Carlos, Groppo; Rogério Heládio Lopes, Motta.
Data sourcesPubmed, Embase, Sciences Citation Index, Cochrane Central Register of Controlled Trials (CENTRAL) and grey literature database of SIGLE were searched from January 1, 1990 to August 20, 2011 with no language restrictions.Study selectionRandomised controlled trials (RCTs) or quasi-RCTs in which the participants were healthy and received additional interventions to conventional orthodontic treatment for accelerating tooth movements were included. Subjects with defects in oral and maxillofacial regions (ie, cleft lip/palate), dental pathologies and medical conditions were excluded.Data extraction and synthesisStudies were selected by two independent reviewers and disagreements were resolved by discussion with a third reviewer. The primary outcomes included accumulative moved distance (AMD) or movement rate (MR) and time required to move the tooth to its destination. Secondary outcomes were pain improvement, anchorage loss, periodontal health, orthodontic caries, pulp vitality and root resorption. The reviewers performed statistical pooling, where possible, according to a priori criteria on the basis of comparability of patient type, treatments and outcomes measured and risk of bias. The reviewers tested for heterogeneity, publication bias and sensitivity. A quality assessment test was conducted to evaluate the method used to measure AMD.ResultsThe authors selected seven RCTs and two quasi-RCTs, which included a total of 101 patients with an age range of 12-26.3 years. Eight studies compared four intervention methods to no intervention group (control group). From them, four studies assessed low laser therapy (LLL), two evaluated corticotomy (CC), one assessed electrical current therapy (EC) and one evaluated pulsed electromagnetic field (PEF). Another study compared dentoalveolar distraction (DAD) vs periodontal distraction (PDD).Quality assessment scores showed that only two studies were of high quality, five studies were of medium quality, while two studies were of low quality. All studies, except one, compared left and right sides of the same participant (split mouth design), and measured the AMD.The method for measuring AMD was reliable in three studies, relatively reliable in one study and unreliable in four studies. The authors only performed pooled AMD mean meta-analysis for the LLL studies. The meta-analysis showed pooled mean AMD of 0.32 (95% confidence interval (CI), 20.04, 0.68), 0.76 (95% CI, 20.14, 1.65), and 0.73 (95% CI, 20.68, 2.14) for one month, two months and three months, respectively. Two LLL studies showed no differences regarding periodontal health and two LLL studies showed no differences in root resorption between LLL intervention and control groups. Compared to control group, one study reported that CS had significantly higher MR and another study showed that CS exhibited larger AMD for one month, two months, three months and four months. Two studies revealed that CS did not show any difference in the periodontal health status. One study reported the EC showed significantly larger AMD for one month, whereas another study reported that PEF induced larger AMD for five + 0.6 months. DAD showed faster MR and less anchorage loss compared to PDD. Teeth remained vital in both DAD and PDD interventions and one out of six cases presented root resorption in the PDD group.ConclusionsAmong the five interventions corticotomy is effective and safe to accelerate orthodontic tooth movement, low-level laser therapy was unable to accelerate orthodontic tooth movement. The level of evidence does not support whether electrical current and pulsed electromagnetic fields are effective in accelerating orthodontic tooth movement and dentoalveolar or periodontal distraction is promising in accelerating orthodontic tooth movement. PMID:25522945
Abdallah, Mohamed-Nur; Flores-Mir, Carlos
Tooth wear is the non-carious loss of tooth tissue, which results from three processes namely attrition, erosion and abrasion. These can occur in isolation or simultaneously. Very mild tooth wear is a physiological effect of aging. This study aims to estimate the prevalence of tooth wear among 16-year old Malay school children and determine a feasible sample size for further study. Fifty-five subjects were examined clinically, followed by the completion of self-administered questionnaires. Qu...
Abd Karim, Nama Bibi Saerah; Ismail, Noorliza Mastura; Naing, Lin; Ismail, Abdul Rashid
...2010-04-01 2010-04-01 false Resin tooth bonding agent. 872.3200 Section 872.3200...Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device material, such...
This case report describes the successful orthodontic tooth movement through the maxillary sinus in an adult patient. A 41-year-old Asian woman had severe lip protrusion and multiple missing posterior teeth. Her orthodontic treatment included the extraction of 2 teeth, maximum retraction of the incisors using the extraction spaces and the existing spaces from the missing molars, and closure of all remaining spaces. Even though the treatment time was extended because of the anatomic and biologic challenges associated with moving posterior teeth over a long distance through the maxillary sinus, a successful outcome was obtained, with significant bone modeling of the maxillary sinus. The results demonstrate that a carefully selected force system can overcome the anatomic limitations of moving tooth against the cortical bone of the maxillary sinus wall in adult patients. PMID:25263152
Oh, Heesoo; Herchold, Kiri; Hannon, Stephanie; Heetland, Kelly; Ashraf, Golnaz; Nguyen, Vince; Cho, Heon Jae
Full Text Available SciELO South Africa | Language: English Abstract in english 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.
Emily, Broadis; Wakisa, Mulwafu.
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 result in many esophageal and extraesophageal adverse conditions. Sleep-related GERD is particularly insidious as the supine position enhances the proximal migration of gastric contents, and normal saliva production is much reduced. Gastric acid will displace saliva easily from tooth surfaces, and proteolytic pepsin will remove protective dental pellicle. Though increasing evidence of associations between GERD and tooth erosion has been shown in both animal and human studies, relatively few clinical studies have been carried out under controlled trial conditions. Suspicion of an endogenous source of acid being associated with observed tooth erosion requires medical referral and management of the patient as the primary method for its prevention and control. PMID:22194748
Ranjitkar, Sarbin; Kaidonis, John A; Smales, Roger J
Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Tuesday, February 03, 2015 About | Contact InfoBites Quick Reference Learn more Pacifiers Have Negative and Positive Effects What is Baby Bottle Tooth Decay? Check Menstrual Calendar for ...
Diet analysis and advice for patients with tooth wear is potentially the most logical intervention to arrest attrition, erosion and abrasion. It is saliva that protects the teeth against corrosion by the acids which soften enamel and make it susceptible to wear. Thus the lifestyles and diet of patients at risk need to be analysed for sources of acid and reasons for lost salivary protection. Medical conditions which put patients at risk of tooth wear are principally: asthma, bulimia nervosa, caffeine addiction, diabetes mellitus, exercise dehydration, functional depression, gastroesophageal reflux in alcoholism, hypertension and syndromes with salivary hypofunction. The sources of acid are various, but loss of salivary protection is the common theme. In healthy young Australians, soft drinks are the main source of acid, and exercise dehydration the main reason for loss of salivary protection. In the medically compromised, diet acids and gastroesophageal reflux are the sources, but medications are the main reasons for lost salivary protection. Diet advice for patients with tooth wear must: promote a healthy lifestyle and diet strategy that conserves the teeth by natural means of salivary stimulation; and address the specific needs of the patients' oral and medical conditions. Individualised, patient-empowering erosion WATCH strategies; on Water, Acid, Taste, Calcium and Health, are urgently required to combat the emerging epidemic of tooth wear currently being experienced in westernised societies. PMID:15880960
Young, William George
Full Text Available SciELO South Africa | Language: English Abstract in english OBJECTIVE: Hypertension may result from changes in dietary quality and nutrient intake. We therefore sought to determine the epidemiological association between tooth loss and hypertension in South African adults. METHODS: This is a secondary data analysis of a cross-sectional survey of a nationally [...] representative sample of adults aged 25 - 70 years who participated in the South African Demographic and Health Survey during 1998 (N=9 098). The primary data were collected using a validated questionnaire, which included information on past experience of tooth loss (partial or complete), use of dental services, tobacco use and other known risk factors for hypertension. Hypertension was defined as having a measured average blood pressure (BP) >160/95 mmHg and/or taking antihypertensive medication. RESULTS: The prevalences of hypertension, any tooth loss and complete edentulousness were 18.1%, 72.2% and 9.4% respectively. Tooth loss was more common among overweight/obese respondents than among those with a normal body mass index (76.7% v. 66.7%; p
Olalekan A, Ayo-Yusuf; Imade J, Ayo-Yusuf.
Cone-beam computed tomography, also termed digital volume tomography, has become a standard technique in dentistry, allowing for fast 3D jaw imaging including denture at moderate spatial resolution. More detailed X-ray images of restricted volumes for post-mortem studies in dental anthropology are obtained by means of micro computed tomography. The present study evaluates the impact of the pipe smoking wear on teeth morphology comparing the abraded tooth with its contra-lateral counterpart. A set of 60 teeth, loose or anchored in the jaw, from 12 dentitions have been analyzed. After the two contra-lateral teeth were scanned, one dataset has been mirrored before the two datasets were registered using affine and rigid registration algorithms. Rigid registration provides three translational and three rotational parameters to maximize the overlap of two rigid bodies. For the affine registration, three scaling factors are incorporated. Within the present investigation, affine and rigid registrations yield comparable values. The restriction to the six parameters of the rigid registration is not a limitation. The differences in size and shape between the tooth and its contra-lateral counterpart generally exhibit only a few percent in the non-abraded volume, validating that the contralateral tooth is a reasonable approximation to quantify, for example, the volume loss as the result of long-term clay pipe smoking. Therefore, this approach allows quantifying the impact of the pipe abrasion on the internal tooth morphology including root canal, dentin, and enamel volumes.
Kofmehl, Lukas; Schulz, Georg; Deyhle, Hans; Filippi, Andreas; Hotz, Gerhard; Berndt-Dagassan, Dorothea; Kramis, Simon; Beckmann, Felix; Müller, Bert
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.
Harding, M A
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
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 solutio...
Débora Alves Nunes Leite Lima; Silva, Andre? Lui?s Faria E.; Flávio Henrique Baggio Aguiar; Priscila Christiane Suzy Liporoni; Egberto Munin; Gláucia Maria Bovi Ambrosano; José Roberto Lovadino
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.
The resonance demodulation technique has been extensively used for rolling bearing diagnostics. This paper presents a scheme of using the resonance demodulation technique for early detection of gear tooth cracks. The objective is to supplement the current techniques of gearbox fault diagnosis based on the synchronous signal averaging technique. The proposed scheme focuses on the fact that gear tooth crack will produce vibration impacts that would excite the structural resonances when the cracked tooth is engaged. Using this scheme, the regular gear meshing harmonics are first removed from the synchronous signal average to generate the residual signal. The residual signal is then band-pass filtered around a structural resonance within the range of gear meshing harmonics. The bandpassed residual signal is demodulated to extract the features related to the crack-induced sudden change in a complete revolution of the gear of interest. A number of statistical measures can then be used on the demodulated signal as an indicator on the existence and status of the crack. In this paper, an analytic signal model is also proposed to describe the gear meshing signal and its processing, the resonance demodulation technique is presented based on the signal model. The method is validated using numerically simulated data, test data from a gear rig, and helicopter in-flight vibration data. The results show that the resonance demodulation technique is an effective tool for the early detection of gear tooth cracks.
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)
Objective. Fusion is a dental anomaly that arises through the union of two adjacent teeth. The case report presents multidisciplinary management of a fused maxillary anterior tooth. Case Report. A 10-year-old boy was referred to the pediatric dental clinic with the chief complaint of a large upper anterior tooth. Intraoral and radiographic examinations indicated fusion between the permanent maxillary right central incisor and a supernumerary tooth. According to the treatment plan, the fused tooth was sectioned, and the mesial portion was removed. The remaining tooth section was restored with composite resin, and the diastema between the central incisors was closed with orthodontic treatment. After an 18-month followup period, the tooth showed no sign of pathosis. Conclusion. The technique described here offers a simple and effective method for restoring a fused tooth that reestablishes function, shape, and esthetics. PMID:24396611
Demircioglu Guler, Derya; Sen Tunc, Emine; Arici, Nursel; Ozkan, Nilüfer
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 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.
New methods of control of tooth bleaching stages through simultaneous measurements of a reflected light and a fluorescence signal are proposed. It is shown that the bleaching process leads to significant changes in the intensity of a scattered signal and also in the shape and intensity of the fluorescence spectra. Experimental data illustrate that the bleaching process causes essential changes in the teeth discoloration in short time as 8-10 min from the beginning of the application procedure. The continuation of the treatment is not necessary moreover the probability of the enamel destroy increases considerably. The proposed optical back control of tooth surface is a base for development of a practical set up to control the duration of the bleaching procedure.
Angelov, I.; Mantareva, V.; Gisbrecht, A.; Valkanov, S.; Uzunov, Tz.
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,...
Smales, Roger J.; Kaidonis, John A.; Sarbin Ranjitkar
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. erosio...
Bardsley, Penny Fleur
Charcot-Marie-Tooth disease (CMT) disease encompasses a genetically heterogeneous group of inherited neuropathies, also known as hereditary motor and sensory neuropathies. CMT results from mutations in more than 40 genes expressed in Schwann cells and neurons causing overlapping phenotypes. The classic CMT phenotype reflects length-dependent axonal degeneration characterized by distal sensory loss and weakness, deep tendon reflex abnormalities, and skeletal deformities. Recent articles have p...
Patzko?, A?gnes; Shy, Michael E.
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...
The 243 sample prospective study shows specifities about black African teeth shade particularly the colour. The results after the use of a study mixed shader composed from three standard shaders are; first: the sequence from the clearest tooth to the less is: central incisor, lateral incisor. Second: the maxillary teeth shade is clearer than the mandibulars. Third, 16% teeth shade not be conducted to determine the objective parameters for black African dentogenics. Therefore: esthetic restorative treatment will be more efficient. PMID:16704024
Koffi, N J; Koffi, K G; Assi, K D
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...
Gutiérrez-Salazar Maria del Pilar; Reyes-Gasga Jorge
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
Full Text Available This study aimed to determine the validity of the digital photocolorimetric (PCM method in matching the color of human teeth. First, two Vitapan Classical shade guides, each containing 16 shade guide teeth, were visually shade matched, and digital photographs of each three pair of shade guide teeth were taken in a color matching booth. Secondly, visual shade matching of the upper central incisors of 48 subjects was performed by two prosthodontists independently in a chair, using the Vitapan Classical shade guide. The three closest shade guide teeth were visually selected and ranked in order of preference, for which digital photographs were taken under ceiling daylight-corrected fluorescent lighting. All digital images were analyzed on a computer screen using software to calculate the color difference between the reference tooth and other teeth in the same digital image. The percent color matching for the shade guide teeth and human teeth was 88% and 75%, respectively. There was no statistically significant difference in matching the tooth color between the shade guide teeth and human teeth. The digital PCM method is valid for the range of human teeth based on the Vitapan Classical shade guide. This method enhances communication with the laboratory personnel in matching the tooth color.
To measure the tooth whitening and the surface and Intrapulpal temperature increase in vitro on freshly extracted upper human central incisors after chemical, Zoom AP light and diode laser activated bleaching. Thirty caries-free upper human incisors were selected. Teeth were divided into three equal groups according to the methods of activation of the bleaching agent (n = 10). A whitening gel containing hydrogen peroxide was applied to the buccal surface of all teeth. Group I was bleached using chemically activated hydrogen peroxide gel, for three applications of 15 min each. Group II was bleached with high intensity advanced power Zoom activation light (Zoom AP), for three applications of 15 min each. Group III was bleached with diode laser activation technique, where the teeth were irradiated with 2 Watt diode laser for three applications of 30 sec each. The whitening degree was assessed using an image analysis system, while temperature rise was recorded using a thermocouple on the external tooth surface and Intrapulpal. The degree of whitening increased significantly in all groups. However, the percentage of whitening was not statistically significantly different between the three groups. In addition, group II showed statistically significant higher mean rise in both surface and pulp temperatures than group I and group III. Chemical bleaching produces the same whitening effect as Zoom AP light and laser, with no surface or pulpal temperature rise. Laser application is faster and produces less surface and pulp temperature increase than Zoom AP light. Diode laser used to activate bleaching gels is not considered dangerous to the vitality of dental pulp using power settings of 2 W.
Abu-ElMagd, D. M.; El-Sayad, I. I.; Abd El-Gawad, L. M.
To measure the tooth whitening and the surface and Intrapulpal temperature increase in vitro on freshly extracted upper human central incisors after chemical, Zoom AP light and diode laser activated bleaching. Thirty caries-free upper human incisors were selected. Teeth were divided into three equal groups according to the methods of activation of the bleaching agent (n = 10). A whitening gel containing hydrogen peroxide was applied to the buccal surface of all teeth. Group I was bleached using chemically activated hydrogen peroxide gel, for three applications of 15 min each. Group II was bleached with high intensity advanced power Zoom activation light (Zoom AP), for three applications of 15 min each. Group III was bleached with diode laser activation technique, where the teeth were irradiated with 2 Watt diode laser for three applications of 30 sec each. The whitening degree was assessed using an image analysis system, while temperature rise was recorded using a thermocouple on the external tooth surface and Intrapulpal. The degree of whitening increased significantly in all groups. However, the percentage of whitening was not statistically significantly different between the three groups. In addition, group II showed statistically significant higher mean rise in both surface and pulp temperatures than group I and group III. Chemical bleaching produces the same whitening effect as Zoom AP light and laser, with no surface or pulpal temperature rise. Laser applicationpulpal temperature rise. Laser application is faster and produces less surface and pulp temperature increase than Zoom AP light. Diode laser used to activate bleaching gels is not considered dangerous to the vitality of dental pulp using power settings of 2 W.
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...
Toru Nikaido; Rena Takahashi; Meu Ariyoshi; Junji Tagami; Alireza Sadr
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.
Jacobsen, Aase Roland
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 birth (P7). The profile search function of Spotfire software was used to select genes with similar expression profile as the enamel genes (Ambn, Amelx, and Enam). Microarray results where validated using real-time reverse transcription-polymerase chain reaction (real-time RT-PCR), and translated proteins identified by Western-blotting. In situ localization of the Ambn, Amelx, and Enam mRNAs were monitored from E12.5 to E17.5 using deoxyoligonucleotide probes. Bioinformatics analysis was used to associate biological functions with differentially expressed (DE; p???0.05) genes. Microarray results showed a total of 4362 genes including Ambn, Amelx, and Enam to be significant DE throughout the time-course. The expression of the three enamel genes was low at pre-natal stages (E11.5-P0) increasing after birth (P1-P7). Profile search lead to isolation of 87 genes with significantly similar expression to the three enamel proteins. These mRNAs were expressed in dental epithelium and epithelium derived cells. Although expression of Ambn, Amelx, and Enam were lower during early tooth development compared to secretory stages enamel proteins were detectable by Western-blotting. Bioinformatic analysis associated the 87 genes with multiple biological functions. Around 35 genes were associated with 15 transcription factors. PMID:22866057
Landin, Maria A Dos Santos Silva; Shabestari, Maziar; Babaie, Eshrat; Reseland, Janne E; Osmundsen, Harald
Hard and soft tissue alveolar ridge deformities occur following the extraction of teeth, creating functional and esthetic tooth replacement challenges, especially in the maxillary anterior smile zone. A surgical technique using a rotated palatal flap for ridge preservation is discussed that, whether combined with conventional fixed dentures or implant treatment for tooth replacement, provides the possibility for greatly improved esthetics. This technique, used in combination with or in preparation for implant treatment, allows for preservation of the alveolar bone height and width for improved implant size and placement options. In addition, preservation and enhancement of the soft tissue at the extraction site provides for soft tissue contours adjacent to the definitive restoration that vary little from those of the original natural tooth. Combined with conventional fixed dentures, use of this technique creates a template of the labial and interproximal sulcus of the extracted tooth, allowing for the molding of an ovate pontic replacement tooth. This results in vastly improved restorative emergence profiles with minimal or no change in the height of the labial gingival margin and the form and height of the interproximal papillae with adjacent teeth. PMID:20228979
Bitter, Robert N
...2010-04-01 false Bracket adhesive resin and tooth conditioner. 872.3750...Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a...
Mammalian molars have undergone heavy scrutiny to determine correlates between morphology and diet. Here, the relationship between one aspect of occlusal morphology, tooth cusp radius of curvature (RoC), and two broad dietary categories, folivory and frugivory, is analyzed in apes. The author hypothesizes that there is a relationship between tooth cusp RoC and diet, and that folivores have sharper teeth than frugivores, and further test the correlation between tooth cusp RoC and tooth cusp size. Eight measures of tooth cusp RoC (two RoCs per cusp) were taken from 53 M(2) s from four species and subspecies of frugivorous apes (Pongo pygmaeus, Pan troglodytes troglodytes, Pan troglodytes schweinfurthii, and Gorilla gorilla gorilla) and two subspecies of folivorous apes (Gorilla beringei beringei, and Gorilla beringei graueri). Phylogenetically corrected ANOVAs were run on the full dataset and several subsets of the full dataset, revealing that, when buccolingual RoCs are taken into account, tooth cusp RoCs can successfully differentiate folivores and frugivores. PCAs revealed that folivores consistently had duller teeth than frugivores. In addition, a weak, statistically significant positive correlation exists between tooth cusp size and tooth cusp RoC. The author hypothesizes differences in tooth cusp RoC are correlated with wear rates, where, per vertical unit of wear, duller cusps will have a longer length of exposed enamel ridge than sharper cusps. More data need to be gathered to determine if the correlation between tooth cusp RoC and tooth cusp size holds true when small primates are considered. PMID:24227163
Berthaume, Michael A
The two distinct molecular forms of cholinesterase (ChE) are acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Our previous studies have reported that ChE is involved in tooth development. However, further experiments are needed to understand the precise action of ChE in tooth development. This study aimed to localise types of ChE in human tooth germs, and identify their distribution pattern. ChE were localised in frozen sections of jaws which were prepared from dead fetuses, neonates and stillborns who were free from visible abnormalities by Karnovsky and Root method. AChE was identified in the inner and outer enamel epithelia including the cervical loop region, stratum intermedium and preameloblasts of tooth germs at bell stage. Secretory ameloblasts were free from staining. The bud and cap stages of permanent tooth germs showed AChE activity on the lingual aspect and top surface of the epithelial ingrowths, respectively. BuChE activity was localised in the degenerating dental lamina. Our study reported the first evidence of localisation of ChE in human tooth development and identified the possible molecular form of ChE in tooth germs as AChE. Also, our results have provided strong evidence to speculate the action of AChE is on the cells of enamel organ during tooth development. PMID:20627235
Nandasena, T L; Jayawardena, C K; Tilakaratne, W M; Nanayakkara, C D
Earlier Metal ceramic crowns were the restorations of choice in the management of traumatic tooth fractures. However, the inherent drawbacks of metal ceramic restorations and the development of newer all ceramic alternatives have resulted in superior esthetic and functional management of these clinical situations. The following case series describes the management of traumatic tooth fractures with Zirconia based all ceramic restorations following endodontic therapy.
Mainak Kanti Saha, Superna Ganguly Saha
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...
Xing, Xueqing; Cai, Quan; Mo, Guang; Du, Rong; Chen, Zhongjun; Wu, Zhonghua
Full Text Available SciELO Brazil | Language: English Abstract in english 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.
Maria del Pilar, Gutiérrez-Salazar; Jorge, Reyes-Gasga.
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 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 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.
Gutiérrez-Salazar Maria del Pilar
Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of 'fracture mechanics' from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth size and enamel thickness. The role of enamel microstructure in determining how cracks initiate and propagate within the enamel (and beyond) is discussed. The picture emerges of teeth as damage-tolerant structures, full of internal weaknesses and defects and yet able to contain the expansion of seemingly precarious cracks and fissures within the enamel shell. How the findings impact on dietary pressures forms an undercurrent of the study. PMID:21507194
Lee, James J-W; Constantino, Paul J; Lucas, Peter W; Lawn, Brian R
To develop an automatic system for utilizing electronic dental records, a data mining system to extract the diagnostic and treatment codes from the records for an intermediate file and automatic drawing of Kaplan-Meier-type survival curves was first created. Then this intermediate file was analyzed with SAS software for the scientific determination of Kaplan-Meier survival of tooth/surface-specific healthy time and survival of restorations in each permanent tooth, health center, and age cohort and also combined. All patients born in 1985, 1990 or 1995 in 28 health centers in Finland were analyzed. Patients classified as caries-active were those who had caries in any first permanent molar under the age of 8 years, while resistant patients did not have caries in these teeth before 10 years. In the younger age cohorts, a shortening of survival of caries-free teeth was seen. The shortest caries-free survival was seen in mandibular and maxillary molars in the youngest age cohort. Occlusal surfaces of molars determined their caries onsets and proximal caries occurred equally in molars, incisors and premolars, whereas canines or mandibular incisors did not have caries in these age cohorts. Caries-prone subjects had the shortest survival in all their teeth. The median longevity of all restorations was 11.7 years, with great variation between health centers and teeth. Because of the great variation between individual teeth, the tooth-specific approach seems appropriate in both caries epidemiology and material sciences. PMID:23406626
Suni, J; Vähänikkilä, H; Päkkilä, J; Tjäderhane, L; Larmas, M
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.
Ivete Jorge, Abrahão; Manoela Domingues, Martins; Emílio, Katayama; João Humberto, Antoniazzi; Angelo, Segmentilli; Márcia Martins, Marques.
Full Text Available Se presenta el caso clínico de un niño de 7 años de edad con enfermedad de Charcot Marie Tooth, atendido en el Servicio de Rehabilitación del Hospital Infantil Norte Docente "Dr. Juan de la Cruz Martínez Maceira" de Santiago de Cuba para recibir tratamiento rehabilitador. Luego del programa terapéutico aplicado el paciente mejoró el trofismo y la fuerza muscular, disminuyeron las deformidades del pie y ocurrieron importantes cambios en la marcha, de modo que la rehabilitación oportuna evitó el tratamiento quirúrgico.The case of a 7 year-old boy with Charcot- Marie-Tooth disease, who was attended at the Rehabilitation Department of "Dr. Juan de la Cruz Martínez Maceira" Northern Teaching Children Hospital in Santiago de Cuba for rehabilitation treatment is reported. After receiving a therapeutic program the patient improved his muscle strenght and trophism, foot deformities decreased and significant changes occurred in gait, so that timely rehabilitation prevented surgical treatment.
Teresa Vidal Pérez
Se presenta el caso clínico de un niño de 7 años de edad con enfermedad de Charcot Marie Tooth, atendido en el Servicio de Rehabilitación del Hospital Infantil Norte Docente "Dr. Juan de la Cruz Martínez Maceira" de Santiago de Cuba para recibir tratamiento rehabilitador. Luego del programa terapéutico aplicado el paciente mejoró el trofismo y la fuerza muscular, disminuyeron las deformidades del pie y ocurrieron importantes cambios en la marcha, de modo que la rehabilitación oportuna...
Teresa Vidal Pérez; Katiuska Ragolta Mógrave; Hilda Alicia Jhones Cabrales; Pastor Perdomo Veranes; Manuel Uriarte Gómez
Full Text Available SciELO Brazil | Language: English Abstract in portuguese Este estudo teve o objetivo de observar a morfologia da interface dente-restauração de diferentes sistemas adesivos em cavidades MOD, por microscopia eletrônica de varredura (MEV). A hipótese do estudo foi de que a morfologia da interface adesiva poderia variar nas diferentes regiões da cavidade MOD [...] , para algum dos 3 sistemas adesivos estudados. Preparos tipo MOD foram confeccionados em 12 terceiros molares humanos hígidos e restaurados com resina composta Filtek Z250 e os seguintes sistemas adesivos: ABF (n=4), Clearfil SE Bond (n=4) (sistemas adesivos autocondicionantes) e Single Bond (n=4) (sistema adesivo de condicionamento ácido total). Após 24 h de armazenamento em água destilada a 37ºC, os dentes foram secionados e preparados para MEV. A morfologia da interface de união variou com o sistema adesivo e com a região analisada. A hipótese do estudo foi aceita, pois a morfologia da interface de união refletiu as características do substrato dental e dos sistemas adesivos testados. Abstract in english The purpose of this study was to assess the morphological characteristics of the tooth/adhesive interface using different adhesive systems in MOD restorations under scanning electron microscopy (SEM). The tested hypothesis was that the morphology of the bonding interface would vary in different area [...] s of MOD restorations for the three adhesive systems. MOD cavities were prepared in 12 sound extracted human third molars and restored with Filtek Z250 composite resin and one of the following adhesive systems: Experimental ABF (n=4), Clearfil SE Bond (n=4) self-etching primers and Single Bond etch-and-rinse adhesive system (n=4). After 24-h storage in distilled water at 37ºC, teeth were sectioned and prepared for SEM. The interfacial morphology varied depending on the adhesive system and also on the evaluated area. The null hypothesis was accepted because the morphology of the tooth/adhesive interface reflected the characteristics of both the dental substrate and the adhesive systems.
Sandra Kiss, Moura; José Fortunato Ferreira, Santos; Rafael Yagüe, Ballester.
Autotransplantation is a viable treatment option to restore esthetics and function impaired by abnormally shaped teeth when a suitable donors tooth is available. This paper describes the autotransplantation and 2-year follow-up of a supernumerary maxillary incisor as a replacement to a misaligned maxillary incisor with abnormal crown morphology and size. The supernumerary incisor was immediately autotransplanted into the extraction site of the large incisor and was stabilized with a bonded se...
Ebru Tirali, R.; Cagla Sar; Ufuk Ates; Metin Kizilkaya; Burcak Cehreli, S.
Charcot-Marie-Tooth (CMT) disease is a common neurogenetic disorder and its heterogeneity is a challenge for genetic diagnostics. The genetic diagnostic procedures for a CMT patient can be explored according to the electrophysiological criteria: very slow motor nerve conduction velocity (MNCV) (45 m/s). Based on the inheritance pattern, intermediate CMT can be divided into dominant (DI-CMT) and recessive types (RI-CMT). GJB1 is currently considered to be associated with X-linked DI-CMT, and MPZ, INF2, DNM2, YARS, GNB4, NEFL, and MFN2 are associated with autosomal DI-CMT. Moreover, GDAP1, KARS, and PLEKHG5 are associated with RI-CMT. Identification of these genes is not only important for patients and families but also provides new information about pathogenesis. It is hoped that this review will lead to a better understanding of intermediate CMT and provide a detailed diagnostic procedure for intermediate CMT. PMID:25326399
Liu, Lei; Zhang, Ruxu
The aim of this study was to determine heritability estimates of treatment responses to a 10% hydrogen peroxide strip-based whitening system in twins. Eighty-five twin pairs were randomly assigned to 10% hydrogen peroxide whitening strips or placebo strips without peroxide. Both twins (monozygotic or dizygotic) received the same treatment. Maxillary teeth were treated for 30 minutes twice daily for 7 days. Efficacy was measured objectively as L* (light-dark), a* (red-green), and b* (yellow-blue) color change from digital images at baseline (?) and day 8. Heritability estimates for tooth whitening treatment responses for changes from day 8 to baseline were obtained using variance-component methodologies. Whitening treatment responses were highly heritable (h(2) = 71.0) for ?b* and ?a*(p whitening treatment responses achieved with 10% hydrogen peroxide strips. PMID:24429255
Corby, Patricia M A; Biesbrock, Aaron; Gerlach, Robert; Corby, Andrea L; Moreira, Alexandre; Schork, Nicholas J; Bretz, Walter A
This study examined tooth retention, tooth loss and use of dental care among aging male narcotics abusers being followed-up for more than 33 years. The cohort of 581 male narcotics addicts admitted to California Civil Addict Program in 1962-1964 was tracked until 1996-1997. As of 1997, 284 (48.9%) were confirmed to be dead. A total of 108 surviving participants completed the oral examination and survey of use of dental services. African American addicts showed the least number of remaining teeth; and African Americans and Hispanics were less likely to utilize dental services compare to Whites. Factors significantly related to tooth retention were abusers' age (p = 0.0006), ethnicity (p = 0.01), income (p dental visits during the 12 months prior to the survey (p prisons and drug treatment programs that include dental care referral and follow-up would be expected to enhance oral and general health among narcotics-addicted individuals. PMID:17062542
Fan, Jing; Hser, Yih-Ing; Herbeck, Diane
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 (Groups 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
Mondelli, José; Sene, Fábio
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.
Full Text Available Supernumerary teeth are defined as any supplementary tooth in addition to usual configuration of twenty deciduous and thirty-two permanent teeth. They are most commonly found in the anterior maxilla and mandibular bicuspid region. Although supernumerary teeth have been reported in the incisor region of the mandible, they are very rare. It has been confirmed that approximately 25% of permanent supernumerary teeth appear in the mouth, the rest remains unerupted. The aim of this study was to present a case of single, erupted, supernumerary tooth in the right incisal region of the mandible. A patient showed up at the dental office complaining about aesthetic problem caused by a supernumerary tooth in mandibular incisal region. On intraoral examination, a supernumerary tooth, conical in shape and labially positioned, between the tooth 42 and 43, was observed. On previously taken panoramic radiogram, six months ago, the supernumerary tooth was undetected. Because the supernumerary tooth was masked by the denser overlying cortical bone, it was difficult to interpret the radiogram correctly. It should be noted that panoramic radiography does not guarantee accurate diagnosis of supernumerary teeth, therefore additional diagnostic methods are required.
In-office tooth whitening using hydrogen peroxide (H?O?) has been practised in dentistry without significant safety concerns for more than a century. While few disputes exist regarding the efficacy of peroxide-based at-home whitening since its first introduction in 1989, its safety has been the cause of controversy and concern. This article reviews and discusses safety issues of tooth whitening using peroxide-based materials, including biological properties and toxicology of H?O?, use of chlorine dioxide, safety studies on tooth whitening, and clinical considerations of its use. Data accumulated during the last two decades demonstrate that, when used properly, peroxide-based tooth whitening is safe and effective. The most commonly seen side effects are tooth sensitivity and gingival irritation, which are usually mild to moderate and transient. So far there is no evidence of significant health risks associated with tooth whitening; however, potential adverse effects can occur with inappropriate application, abuse, or the use of inappropriate whitening products. With the knowledge on peroxide-based whitening materials and the recognition of potential adverse effects associated with the procedure, dental professionals are able to formulate an effective and safe tooth whitening regimen for individual patients to achieve maximal benefits while minimising potential risks. PMID:23846062
Li, Y; Greenwall, L
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.
Dahl, J E; Pallesen, Ulla
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)s as compared to females. (author)
The aim of this study was to achieve aesthetically pleasing soft tissue contours in a severely compromised tooth in the anterior region of the maxilla. For a right-maxillary central incisor with localized advanced chronic periodontitis a tooth extraction followed by reconstructive procedures and delayed implant placement was proposed and accepted by the patient. Guided bone regeneration (GBR) technique was employed, with a biphasic calcium-phosphate (BCP) block graft placed in the extraction socket in conjunction with granules of the same material and a resorbable barrier membrane. After 6 months of healing, an implant was installed. The acrylic provisional restoration remained in situ for 3 months and then was substituted with the definitive crown. This ridge reconstruction technique enabled preserving both hard and soft tissues and counteracting vertical and horizontal bone resorption after tooth extraction and allowed for an ideal three-dimensional implant placement. Localized severe alveolar bone resorption of the anterior maxilla associated with chronic periodontal disease can be successfully treated by means of ridge reconstruction with GBR and delayed implant insertion; the placement of an early-loaded, Morse taper connection implant in the grafted site was effective to create an excellent clinical aesthetic result and to maintain it along time. PMID:25431687
Mangano, Francesco Guido; Zecca, Piero; Luongo, Fabrizia; Iezzi, Giovanna; Mangano, Carlo
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 ments at the same place on the same tooth in order to follow the evolution) and safety tests before in vivo analyses
Full Text Available The approach used until recently concerning the phenomena of dental abfraction points to the conclusion that the cervical area of the tooth, were this type of lesion usually occur, concentrates the stress resulted from the action of the forces applied on various areas on the crown. Moreover, any lesion in the cervical area facilitates the possibility of its advance into the tooth, ultimately fracturing it. Our paper presents a FEM (finite element method study on the results of a mechanical analysis of the phenomena involving the tooth damaged by cervical lesions.
Gemination, a relatively uncommon dental anomaly, is characterized by its peculiar representation as a tooth with a bifid crown and a common root and root canal. It usually occurs in primary dentition. To come across gemination in a supernumerary tooth is a rare phenomenon. The purpose of this paper is to present a unique case of hyperdontia wherein gemination in an impacted supernumerary tooth resulted in a trifid crown unlike the usual bifid crown. The role of conventional radiographs as well as computed tomography, to accurately determine the morphology and spatial location, and to arrive at a diagnosis, is also emphasized in this paper.
Ather, Amber; Ather, Hunaiza; Sheth, Sanket Milan; Muliya, Vidya Saraswathi [Manipal College of Dental Sciences, Manipal (Korea, Republic of)
Gemination, a relatively uncommon dental anomaly, is characterized by its peculiar representation as a tooth with a bifid crown and a common root and root canal. It usually occurs in primary dentition. To come across gemination in a supernumerary tooth is a rare phenomenon. The purpose of this paper is to present a unique case of hyperdontia wherein gemination in an impacted supernumerary tooth resulted in a trifid crown unlike the usual bifid crown. The role of conventional radiographs as well as computed tomography, to accurately determine the morphology and spatial location, and to arrive at a diagnosis, is also emphasized in this paper.
Impaction of a maxillary canine is common. Orthodontic realignment is not always the therapy of choice. Instead, the impacted tooth can be extracted and replaced by an implant. The replacement of a single tooth with an implant in the anterior maxilla is a topic of interest for clinicians because of its esthetic implications, mostly when immediate loading has been planned. This article describes a clinical case in which an impacted maxillary canine was replaced by an immediately restored osseo...
Debernardi, Cesare Lorenzo
Two patients are described with Charcot-Marie-Tooth disease and chronic peripheral neuropathy. Both had dyspnoea, orthopnoea, and evidence of severe diaphragm weakness. Expiratory muscle function was well preserved and abnormalities of gas exchange during sleep were only minor.
Laroche, C. M.; Carroll, N.; Moxham, J.; Stanley, N. N.; Evans, R. J.; Green, M.
... Causes/Inheritance Causes of Charcot-Marie-Tooth disease (CMT) Peripheral nerves control movement by relaying impulses from ... problems in the body’s extremities. Inheritance patterns in CMT Although CMT can look very similar to an ...
Triple teeth may result from fusion, gemination or concrescence causing transient esthetic and functional problems in primary dentition and retardation or alteration of development and eruption of permanent successors. We report an unusual case of a boy aged five with fusion among maxillary left primary central incisor, lateral incisor and a supernumerary tooth concomitant with agenesis of permanent lateral incisor. A review of literature on triple tooth was done along with a proposed classification of the triple teeth. PMID:24015024
Shilpa, Gaddam; Nuvvula, Sivakumar
Abstract Background The choice between several treatment options for replacing a single missing tooth is influenced by clinical, dentist- and patient-immanent factors. This study aimed to determine the patient factors that would affect the treatment decision to replace a single missing tooth and to assess the satisfaction with several options. Method 200 volunteers involved (121 females and 79 males) divided into four groups, Group A: consisted of patients with ...
Al-Quran Firas A; Al-Ghalayini Raed F; Al-Zu'bi Bashar N
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...
Volponi, Ana Angelova; Pang, Yvonne; Sharpe, Paul T.
Dental caries affects most adults worldwide; however, the risk factors for dental caries do not necessarily exert their effects uniformly across all tooth surfaces. Instead, the actions of some risk factors may be limited to a subset of teeth/surfaces. Therefore, we used hierarchical clustering on tooth surface-level caries data for 1,068 Appalachian adults (ages 18-75 yrs) to group surfaces based on co-occurrence of caries. Our cluster analysis yielded evidence of 5 distinct g...
Shaffer, J. R.; Feingold, E.; Wang, X.; Weeks, D. E.; Weyant, R. J.; Crout, R.; Mcneil, D. W.; Marazita, M. L.
Full Text Available Earlier Metal ceramic crowns were the restorations of choice in the management of traumatic tooth fractures. However, the inherent drawbacks of metal ceramic restorations and the development of newer all ceramic alternatives have resulted in superior esthetic and functional management of these clinical situations. The following case series describes the management of traumatic tooth fractures with Zirconia based all ceramic restorations following endodontic therapy.
Mainak Kanti Saha, *Superna Ganguly Saha
The tooth root cementum is a thin, mineralized tissue covering the root dentin that is present primarily as acellular cementum on the cervical root and cellular cementum covering the apical root. While cementum shares many properties in common with bone and dentin, it is a unique mineralized tissue and acellular cementum is critical for attachment of the tooth to the surrounding periodontal ligament (PDL). Resources for methodologies for hard tissues often overlook cementum and approaches tha...
Foster, Brian L.
Introduction: Nasal teeth eruption is a rare phenomenon. The variability of symptoms and generic history makes the diagnosis difficult. This difficulty is more challenging when the tooth is placed in the depth of septum. Case Report: Our case is an example of this problem. Herein, we present a case of intraseptal tooth with nasal obstruction and septal deviation and recurrent sinusitis. We present preoperative imaging. Conclusion: Great suspicion may helpful for preoperative diagnosis a...
Saleh Mohebbi; Oveis Salehi; Sedighe Ebrahimpoor
Full Text Available Introduction: Nasal teeth eruption is a rare phenomenon. The variability of symptoms and generic history makes the diagnosis difficult. This difficulty is more challenging when the tooth is placed in the depth of septum. Case Report: Our case is an example of this problem. Herein, we present a case of intraseptal tooth with nasal obstruction and septal deviation and recurrent sinusitis. We present preoperative imaging. Conclusion: Great suspicion may helpful for preoperative diagnosis and good deciding.
The objective of this report is to describe combined orthodontic and endodontic treatment of a fused mandibular premolar with supernumerary tooth. The patient was a 15 year old girl seeking orthodontic treatment for the correction of maxillary and mandibular crowding. Cephalometric examination revealed skeletally Class I relationship. The panoramic radiograph showed a fused tooth with two separate pulp chambers and two separate root canals connecting in apical third. After the endodontic trea...
Gadimli, Cengiz; Sari, Zafer
As part of a program to study fundamental mechanisms of gear noise, static and dynamic gear tooth strain measurements were made on the NASA gear-noise rig. Tooth-fillet strains from low-contact ratio-spur gears were recorded for 28 operating conditions. A method is introduced whereby strain gage measurements taken from both the tension and compression sides of a gear tooth can be transformed into the normal and frictional loads on the tooth. This technique was applied to both the static and dynamic strain data. The static case results showed close agreement with expected results. For the dynamic case, the normal-force computation produced very good results, but the friction results, although promising, were not as accurate. Tooth sliding friction strongly affected the signal from the strain gage on the tensionside of the tooth. The compression gage was affected by friction to a much lesser degree. The potential of the method to measure friction force was demonstrated, but further refinement will be required before this technique can be used to measure friction forces dynamically with an acceptable degree of accuracy.
Rebbechi, Brian; Oswald, Fred B.; Townsend, Dennis P.
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
Bonds, John; Pollan-White, Sarah; Xiang, Lilin; Mues, Gabriele; D'Souza, Rena
Endogenous regeneration through cell homing provides an alternative approach for tissue regeneration, except cell transplantation, especially considering clinical translation. However, tooth root regeneration through cell homing remains a provocative approach in need of intensive study. Both platelet-rich fibrin (PRF) and treated dentin matrix (TDM) are warehouses of various growth factors, which can promote cell homing. We hypothesized that endogenous stem cells are able to sense biological cues from PRF membrane and TDM, and contribute to the regeneration of tooth root, including soft and hard periodontal tissues. Therefore, the biological effects of canine PRF and TDM on periodontal ligament stem cells (PDLSCs) and bone marrow mesenchymal stem cells (BMSCs) were evaluated respectively in vitro. Beagle dogs were used as orthotopic transplantation model. It was found that PRF significantly recruited and stimulated the proliferation of PDLSCs and BMSCs in vitro. Together, PRF and TDM induced cell differentiation by upregulating the mineralization-related gene expression of bone sialoprotein (BSP) and osteopotin (OPN) after 7 days coculture. In vivo, transplantation of autologous PRF and allogeneic TDM into fresh tooth extraction socket achieved successful root regeneration 3 months postsurgery, characterized by the regeneration of cementum and periodontal ligament (PDL)-like tissues with orientated fibers, indicative of functional restoration. The results suggest that tooth root connected to the alveolar bone by cementum-PDL complex can be regenerated through the implantation of PRF and TDM in a tooth socket microenvironment, probably by homing of BMSCs and PDLSCs. Furthermore, bioactive cues and inductive microenvironment are key factors for endogenous regeneration. This approach provides a tangible pathway toward clinical translation. PMID:25111570
Ji, Baohui; Sheng, Lei; Chen, Gang; Guo, Shujuan; Xie, Li; Yang, Bo; Guo, Weihua; Tian, Weidong
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 DFseverity, 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 goodpredictor/indicator of DF severity.
Marc Daniel Grynpas
Objective: To observe the difference in dimension of teeth among adult females with and without malocclusion. Methods: The cross-sectional study was conducted at Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi, from April 2011 to April 2013, and used non-probability consecutive sampling. Mesiodistal and buccolingual crown dimensions were measured on study casts by using digital sliding caliper in 2 groups of females. Group1 had 150 subjects with normal occlusion, while Group 2 had 234 with malocclusion. Independent t test was conducted to evaluate the difference between the dimensions of teeth of the two groups. Statistical analysis was done on SPSS version 16, and p value was considered significant at 0.05. Results: Overall, the difference between the groups showed a greater tooth dimension in the malocclusion group of population compared to the normal group, and the most significant difference was observed in the mesiodistal dimension of maxillary 2nd premolar, which was 0.9+-0.6801mm greater in dimension in the malocclusion group compared to the normal group. The least difference was observed in the buccolingual dimension of the mandibular central incisor where the malocclusion group had only 0.08+-0.5247mm larger mandibular central incisors in the buccolingual dimension compared to the normal group. Conclusion: Mesiodistal and buccolingual crown dimensions were characteristically larger in the malocclusion group. (author)
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)
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
Borrero-Lopez, Oscar; Pajares, Antonia; Constantino, Paul J; Lawn, Brian R
Few recent studies have examined the histological basis for tooth attachment in squamates. In the past few years, a surge of interest in this topic has led to the intriguing suggestion that the major tissues derived from the tooth germ (enamel, dentine, cementum and alveolar bone), are conservative and are present in all amniotes. In this study, we describe the histology and development of the tooth attachment complex in Varanus rudicollis, the rough-neck monitor. We provide the first published evidence for the role of cementum and alveolar bone in tooth attachment in varanoid lizards. In Varanus, cementum is deposited on the external surface of the tooth root as well as at the base of the tooth, where it plays a role in the attachment of the tooth to the jawbone. Alveolar bone is also involved in tooth ankylosis. Our results support the hypothesis that the major tooth germ tissues are found in all amniotes. We provide insights into the structure and development of plicidentine, defined as infolding of the dentine around the tooth base. This feature is unique to varanoids among extant tetrapods and is the third tissue implicated in tooth attachment in Varanus. Plicidentine develops asymmetrically along the labial-lingual axis of a tooth. Varanus is characterized by the presence of both primary and higher-order lamellae, which anastomose to form a honeycomb-like surface that then interacts with the more basal attachment tissues. PMID:21618268
Maxwell, Erin E; Caldwell, Michael W; Lamoureux, Denis O; Budney, Lisa A
Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se presenta el caso clínico de un niño de 7 años de edad con enfermedad de Charcot Marie Tooth, atendido en el Servicio de Rehabilitación del Hospital Infantil Norte Docente "Dr. Juan de la Cruz Martínez Maceira" de Santiago de Cuba para recibir tratamiento rehabilitador. Luego del programa terapéut [...] ico aplicado el paciente mejoró el trofismo y la fuerza muscular, disminuyeron las deformidades del pie y ocurrieron importantes cambios en la marcha, de modo que la rehabilitación oportuna evitó el tratamiento quirúrgico. Abstract in english The case of a 7 year-old boy with Charcot- Marie-Tooth disease, who was attended at the Rehabilitation Department of "Dr. Juan de la Cruz Martínez Maceira" Northern Teaching Children Hospital in Santiago de Cuba for rehabilitation treatment is reported. After receiving a therapeutic program the pati [...] ent improved his muscle strenght and trophism, foot deformities decreased and significant changes occurred in gait, so that timely rehabilitation prevented surgical treatment.
Teresa, Vidal Pérez; Katiuska, Ragolta Mógrave; Hilda Alicia, Jhones Cabrales; Pastor, Perdomo Veranes; Manuel, Uriarte Gómez.
Premature exfoliation of primary or permanent teeth in children or adolescents is extremely rare and it can be a manifestation of an underlying systemic disease. This study aims to present the histological aspects associated with early tooth loss in a case of periodontal disease developed without local inflammation and with minimal periodontal pockets and attachment loss. The maxillary left second premolar was extracted together with a gingival collar attached to the root surface. The histological analysis recorded the resorption of the cementum in multiple areas of the entire root surface with the connective tissue of the desmodontium invading the lacunae defects. The connective tissue rich in cells occupied the periodontal ligamentar space and the resorptive areas. No inflammation was obvious in the periodontal ligament connective tissue. This report may warn clinicians about the possibility of the association of cemental abnormalities with early tooth loss. PMID:23303038
Petru?iu, S A; Buiga, Petronela; Roman, Alexandra; Danciu, Theodora; Mihu, Carmen Mihaela; Mihu, D
This paper deals with the contact stress, power loss, and pitting of spur gear tooth in altered tooth-sum gearing for a tooth-sum of 100 teeth when altered by ±4% tooth-sum. Analytical and experimental methods were performed to investigate and compare the altered tooth-sum gearing against the standard tooth-sum gearing. The experiments were performed using a power recirculating type test rig. The tooth loads for the experimental investigations were determined considering the surface durability of gears. A clear picture of the surface damage was obtained using a scanning electron microphotograph. The negative alteration in the tooth-sum performed better than the positive alteration in a tooth-sum operating between specified center distances.
Sachidananda, H. K.; Gonsalvis, Joseph; Prakash, H. R.
Full Text Available SciELO Brazil | Language: English Abstract in english Proper occlusion depends on the correct width ratio between upper and lower teeth, known as Bolton's ratio. In fact, this ratio can be calculated for each pair of teeth from the central incisor to the first permanent molar. This set of ratios, known as comprehensive cumulative percentage ratios (CPR [...] s), can be used not only to determine which tooth or teeth have a tooth width discrepancy, but can also enable the partial graphical analysis of tooth width discrepancy when there is agenesis of certain permanent teeth. Although CPRs have been calculated for Caucasians, tooth width is known to vary depending on racial origin. Therefore, a test of differences between racial groups should be carried out. If these ratios of the Caucasians and Bangkokians are significantly different, the ratio of the Bangkokians is recommended. The objective of this study was to measure tooth size disproportion for Thai patients and to calculate a corresponding set of CPRs. Thirty-seven pairs of dental models were made from a group of Bangkok residents with normal occlusion. Mesiodistal tooth width was measured for each model. The intra- and inter-examiner measurement errors were ascertained as insignificant (p > 0.05). CPRs were then calculated and compared to those derived from other studies. Ten of thirteen CPRs were significantly different from corresponding values derived from Caucasians. We conclude that tooth width ratios vary between different racial groups, and therefore that these should be calculated specifically for each patient racial group.
Somchai, Manopatanakul; Narumon, Watanawirun.
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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
José, Mondelli; Fábio, Sene; Renata Pereira, Ramos; Ana Raquel, Benetti.
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.
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 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.
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.
S E Jabbarifar
Monte Carlo (MC) simulation was implemented in a three dimensional tooth model to simulate the light propagation in the tooth for antibiotic photodynamic therapy and other laser therapy. The goal of this research is to estimate the light energy deposition in the target region of tooth with given light source information, tooth optical properties and tooth structure. Two use cases were presented to demonstrate the practical application of this model. One case was comparing the isotropic point source and narrow beam dosage distribution and the other case was comparing different incident points for the same light source. This model will help the doctor for PDT design in the tooth.
Fu, Yongji; Jacques, Steven L.
It is shown that the results of retrospective EPR dosimetry by tooth enamel are essentially determined by the fact that tooth enamel is the mineral of biological origin. The structure of tooth enamel, properties of radiation defects and the role of metabolism in tooth enamel are discussed. It is shown that at deep metamorphic modifications tooth enamel don't save information about its radiation history. The reliability and accuracy of retrospective EPR dosimetry are discussed. Because after Chernobyl accident have passed 10 years the application of tooth enamel for reconstruction of doses which are connected with Chernobyl accident need care and additional investigations
Tooth wear has been studied in a dentally attending population, aged 46-85 years. The level of tooth wear was recorded for 100 persons using the tooth wear index of Smith and Knight. Aetiology was assessed using a history/questionnaire/examination. Erosion/attrition were postulated in 98 persons while abrasion was present in 82. All demonstrated some tooth wear and in 6.93% of 7,822 surfaces this was defined as pathological according to the threshold levels associated with the index. 84 persons had pathological wear on some surfaces but this was predominately cervical, only 12 persons showing pathological wear on the occlusal/incisal surfaces. Occlusal contact area was measured using imprints in soft opaque wax, transmitted light and a charge-coupled linear scanning array. The array is moved at 90 degrees to its axis by a linear translator to produce an image consisting of 1,600 lines, each of 2,048 pixels. This image is converted to hard copy using a DEC DDP 11/23 computer which will also give area measurements. Occlusal contact area ranged from 3.16 to 194.40 sq mm with a mean of 59.23 sq mm. Tooth wear is a significant clinical problem in this population. Wear on the occlusal/incisal surfaces is more common in older age groups and in males but could not be related to occlusal contact area or denture status by the methods used. PMID:2077569
Poynter, M E; Wright, P S
We present a Monte Carlo model for optical coherence tomography (OCT) imaging of human tooth. The model is implemented by combining the simulation of a Gaussian beam with simulation for photon propagation in a two-layer human tooth model with non-parallel surfaces through a Monte Carlo method. The geometry and the optical parameters of the human tooth model are chosen on the basis of the experimental OCT images. The results show that the simulated OCT images are qualitatively consistent with the experimental ones. Using the model, we demonstrate the following: firstly, two types of photons contribute to the information of morphological features and noise in the OCT image of a human tooth, respectively. Secondly, the critical imaging depth of the tooth model is obtained, and it is found to decrease significantly with increasing mineral loss, simulated as different enamel scattering coefficients. Finally, the best focus position is located below and close to the dental surface by analysis of the effect of focus positions on the OCT signal and critical imaging depth. We anticipate that this modeling will become a powerful and accurate tool for a preliminary numerical study of the OCT technique on diseases of dental hard tissue in human teeth. (paper)
Full Text Available Reptiles have a diverse array of tooth shapes, from simple unicuspid to complex multicuspid teeth, reflecting functional adaptation to a variety of diets and eating styles. In addition to cusps, often complex longitudinal labial and lingual enamel crests are widespread and contribute to the final shape of reptile teeth. The simplest shaped unicuspid teeth have been found in piscivorous or carnivorous ancestors of recent diapsid reptiles and they are also present in some extant carnivores such as crocodiles and snakes. However, the ancestral tooth shape for squamate reptiles is thought to be bicuspid, indicating an insectivorous diet. The development of bicuspid teeth in lizards has recently been published, indicating that the mechanisms used to create cusps and crests are very distinct from those that shape cusps in mammals. Here, we introduce the large variety of tooth shapes found in lizards and compare the morphology and development of bicuspid, tricuspid and pentacuspid teeth, with the aim of understanding how such tooth shapes are generated. Next, we discuss whether the processes used to form such morphologies are conserved between divergent lizards and whether the underlying mechanisms share similarities with those of mammals. In particular, we will focus on the complex teeth of the chameleon, gecko, varanus and anole lizards using SEM and histology to compare the tooth crown morphology and embryonic development.
Prior to Charcot and Marie's and Tooth's reports, patients with peroneal muscular atrophy had been described by Virchow, Eulenburg, Friedreich, Osler, and others. In February 1886, Charcot and Marie published their original description of five patients who had what they called Progressive Muscular Atrophy. They surmised that the lesion could be in the spinal cord. Three months later, Tooth presented his M.D. degree thesis entitled "Peroneal Type of Progressive Muscular Atrophy", to the University of Cambridge, UK. Tooth localized the pathology to the peripheral nerves. Dyck and Lambert (Arch Neurol 18:619-625, 1968) classified several CMT kinships based on differences in modes of inheritance, natural history, biochemical features, nerve conduction velocity, and pathologic characteristics. This article will focus on historical landmarks and major discoveries pertinent to the disease since its original description through the second half of the twentieth century. PMID:25201224
Kazamel, Mohamed; Boes, Christopher J
An implant-supported crown or conventionally fixed partial denture is the most common treatment modality to replace a missing anterior tooth but a more conservative approach, with a fiber reinforced composite resin FPD, can be used to replace a missing anterior tooth in young patients or when the patient does not agree for an implant, or conventional FPD or RPD therapy. It is an esthetic, conservative single sitting chairside procedure which can be used as a definitive treatment alternative in certain clinical situations for esthetic and functional replacement of a missing anterior tooth. To achieve desirable results, putty matrix was used for proper positioning of the pontic during direct fabrication of FRCFPD. PMID:25254122
Singh, Kunwarjeet; Gupta, Nidhi; Unnikrishnan, Nandini; Kapoor, Vikram; Arora, Dhruv; Khinnavar, Poonam K
Tooth surface loss can present in a variety of ways, some of which can appear rather strange on first examination. This case report demonstrates an unusual presentation of tooth surface loss (TSL) and its subsequent treatment. This loss of hard dental tissue appeared to be affecting the whole of the patient's remaining dentition, both lingually and buccally. Detailed questioning revealed the origins of this problem which turned out to be due to excessive use of an intra-oral Miswak chewing stick. Cinical Relevance: This article will enable clinicians to understand the importance of specific, targeted history-taking, involving a rare case of tooth surface loss as well as the use of minimally destructive restoration composites and a fibre-reinforced composite bridge. PMID:24930258
Karia, Roshni; Kelleher, Martin G
Monitoring of agent diffusion within tooth tissues is important in a wide context of tooth therapy (diffusion of medicinal preparations) and cosmetics (chemical whitening agents). We report here the results of optical coherence tomography (OCT) monitoring of diffusion of water and glycerol as clearing agents in samples of human tooth tissue. The diffusion process is analyzed by monitoring the changes in the OCT signal slope and the depth-resolved amplitude of OCT signal from a sample. Slow temporal kinetics of the mean attenuation coefficient was measured to monitor a saturable optical clearing due to the diffusion of the agent. The average permeability coefficient was estimated by dividing the measured thickness of the selected region by the time it took for the agent to diffuse through. The experimental results demonstrate that OCT can be an efficient tool in the study of agent diffusion through hard tissues.
Trunina, N. A.; Lychagov, V. V.; Tuchin, V. V.
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.
Spin-Neto, Rubens; Pontes, Ana Emília Farias
The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm(2). Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ? 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment. PMID:22350425
Genc, Ghizlane; Kocadereli, Ilken; Tasar, Ferda; Kilinc, Kamer; El, Sibel; Sarkarati, Bahram
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
Ciocan, Delia Ioana; Stanciu, Drago?; Popescu, Manuela Anca; Miculescu, Florin; Plotog, Ioan; V?rzaru, Gauden?iu; Ciocan, Lucian Toma
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.
Litvin, F. L.; Chen, N. X.
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.
Full Text Available Introduction. The mathematical model of the abutment tooth is the starting point of the finite element analysis of stress and deformation of dental structures. The simplest and easiest way is to form a model according to the literature data of dimensions and morphological characteristics of teeth. Our method is based on forming 3D models using standard geometrical forms (objects in programmes for solid modeling. Objective. Forming the mathematical model of abutment of the second upper premolar for finite element analysis of stress and deformation of dental structures. Methods. The abutment tooth has a form of a complex geometric object. It is suitable for modeling in programs for solid modeling SolidWorks. After analyzing the literature data about the morphological characteristics of teeth, we started the modeling dividing the tooth (complex geometric body into simple geometric bodies (cylinder, cone, pyramid,.... Connecting simple geometric bodies together or substricting bodies from the basic body, we formed complex geometric body, tooth. The model is then transferred into Abaqus, a computational programme for finite element analysis. Transferring the data was done by standard file format for transferring 3D models ACIS SAT. Results. Using the programme for solid modeling SolidWorks, we developed three models of abutment of the second maxillary premolar: the model of the intact abutment, the model of the endodontically treated tooth with two remaining cavity walls and the model of the endodontically treated tooth with two remaining walls and inserted post. Conclusion Mathematical models of the abutment made according to the literature data are very similar with the real abutment and the simplifications are minimal. These models enable calculations of stress and deformation of the dental structures. The finite element analysis provides useful information in understanding biomechanical problems and gives guidance for clinical research.
In six commercial pig farms, we compared the effects of two methods of tooth resection (tooth clipping with pliers and tooth grinding with a rotating grindstone) on teeth themselves, on skin lesions of piglets and of sow udders as well as on litter growth and survival. An intact group was included for control. Treatments were balanced within herds with sows assigned to one of the three experimental treatments. Observations were from 107 sows and their litters (n = 35 or 36 litters/group) at farrowing (day 0) and approximately 8, 15 and 27 days later. Tooth resection was done within 24 h of birth after cross-fostering. Data concerning sows' lesions were analyzed on a farm basis and those concerning piglets' mortality, growth and skin lesions were analyzed on a litter basis. Frequency and severity of udder lesions differed between treatments at farrowing and on day 8; differences depended on the location of the teats (front, median or rear). Litter size and liveweight of piglets on day 0 (11.9+/-0.1 pigs, 1.51+/-0.03 kg) and on day 27 (10.8+/-0.1 pigs, 8.08+/-0.10 kg) were similar in the three groups (mean+/-S.E.M., n = 107). Skin lesions on piglets were more frequent and/or severe in intact than in clipped piglets on days 8 and 27, whereas ground piglets had intermediate results. Because the length of the teeth was similar after clipping and grinding (P > 0.1), tooth shortening itself does not explain the differences between treatments. Overall, tooth resection had very little effect on sow mammary injuries and litter performance. It might reduce skin damage to piglets (especially, when it is performed by clipping) but teeth are severely injured. PMID:15899293
Gallois, M; Le Cozler, Y; Prunier, A
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.
Nascimento, Marcelle M; Gordan, Valeria V
Tooth development is a highly heritable process which relates to other growth and developmental processes, and which interacts with the development of the entire craniofacial complex. Abnormalities of tooth development are common, with tooth agenesis being the most common developmental anomaly in humans. We performed a genome-wide association study of time to first tooth eruption and number of teeth at one year in 4,564 individuals from the 1966 Northern Finland Birth Cohort (NFBC1966) and 1,...
Pillas, D.; Hoggart, C. J.; Evans, D. M.; O Reilly, P. F.; Sipila, K.; Lahdesmaki, R.; Millwood, I. Y.; Kaakinen, M.; Netuveli, G.; Blane, D.; Charoen, P.; Sovio, U.; Pouta, A.; Freimer, N.; Hartikainen, A. L.
Teeth represent an essential component of the foraging apparatus for any mammal, and tooth wear can have significant implications for survival and reproduction. This study focuses on tooth wear in wild baboons in Amboseli, southern Kenya. We obtained mandibular and maxillary tooth impressions from 95 baboons and analyzed digital images of replicas made from these impressions. We measured tooth wear as the percent dentine exposure (PDE, the percent of the occlusal surface on which dentine was ...
Galbany, Jordi; Altmann, Jeanne; Pe?rez-pe?rez, Alejandro; Alberts, Susan C.
Having analyzed the shortcoming of current measurement method of involute cylinder gear wheel tooth form error and the reason of error, measurement theory and implementation method of the complete tooth form error of the involute cylindrical gear have been proposed; mathematical model of fitting actual tooth curve based on cubic spline function has been derived and the determination of boundary condition has been given; feasibility of measurement and evaluation method for complete tooth form error has been verified by experiment.
Huang, Fugui; Cui, Changcai; Zhang, Rencheng
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.
Demortier, Guy [Department of Physics, University of Namur, 61, rue de Bruxelles, B5000 Namur (Belgium)], E-mail: email@example.com; Nammour, Samir [Faculty of Medicine, University of Liege, 8, rue Paul Spaak, B-1000 Bruxelles (Belgium)
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.
Camilo Aquino Melgaço
This study evaluated rapid maxillary expansion (RME) dentoskeletal effects by means of computed tomography (CT), comparing tooth tissue-borne and tooth-borne expanders. The sample comprised eight girls aged 11 to 14 years presenting Class I or II malocclusions with posterior unilateral or bilateral crossbite that were randomly divided into two treatment groups, palatal acrylic (Haas-type) and hygienic (Hyrax) expanders. All appliances were activated up to the full seven mm capacity of the expansion screw. The patients were subjected to a spiral CT scan before expansion and after a three-month retention period when the expander was removed. One-millimeter-thick axial sections were scanned parallel to the palatal plane, comprising the dentoalveolar area and the base of the maxilla up to the inferior third of the nasal cavity. Multiplanar reconstruction was used to measure maxillary transverse dimensions and posterior teeth inclination by means of a computerized method. The results showed that RME produced a significant increase in all measured transverse linear dimensions, decreasing in magnitude from dental arch to basal bone. The transverse increase at the level of the nasal floor corresponded to one-third of the amount of screw activation. Tooth-borne (Hyrax) and tooth tissue-borne (Haas-type) expanders tended to produce similar orthopedic effects. In both methods, RME led to buccal movement of the maxillary posterior teeth, by tipping and bodily translation. The second premolars displayed more buccal tipping than the appliance-supporting teeth. The tooth tissue-borne expander produced a greater change in the axial inclination of appliance-supporting teeth, especially first premolars, compared with the tooth-borne expander. PMID:16097223
Garib, Daniela G; Henriques, José Fernando Castanha; Janson, Guilherme; Freitas, Marcos Roberto; Coelho, Regis Antonio
Increased duration of fixed orthodontic treatments leads to increased tooth root degeneration, gum inflammation and tooth caries. To decrease the time period of orthodontic treatment, it is essential to facilitate tooth movement or in other words increase the speed of bone remodeling. Use of low level laser therapy is a method for achieving this goal.
Soghra Yassaei; Reza Fekrazad; Neda Shahraki
Localised anterior tooth wear can be managed using minimally invasive techniques with conservation of tooth structure and preservation of pulp vitality. This article describes and illustrates with two clinical cases, the management of localised tooth wear, with the restoration of canine guidance by a combination of gold palatal veneers and direct composite restorations. PMID:23518974
Eliyas, S; Martin, N
Full Text Available Increased duration of fixed orthodontic treatments leads to increased tooth root degeneration, gum inflammation and tooth caries. To decrease the time period of orthodontic treatment, it is essential to facilitate tooth movement or in other words increase the speed of bone remodeling. Use of low level laser therapy is a method for achieving this goal.
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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%.
Carlos, Flores-Mir; Mark R, Rosenblatt; Paul W., Major; Jason P., Carey; Giseon, Heo.
Tooth enamel, extracted from molars, was irradiated with 66 keV X-rays, with doses up to 1 Gy. 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 magneton) 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 0 Gy2 =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. (author)
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.
Godinho, J.; Silveira, J.; Mata, A.; Carvalho, M. L.; Pessanha, S.
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
Duverger, Olivier; Ohara, Takahiro; Shaffer, John R; Donahue, Danielle; Zerfas, Patricia; Dullnig, Andrew; Crecelius, Christopher; Beniash, Elia; Marazita, Mary L; Morasso, Maria I
It is shown that metamorphic modifications in tooth enamel have an essential influence on the result of EPR dosimetry. The metamorphic modifications in minerals of biological origin proceed more quickly than in usual natural minerals. The approaches which at present are applied for reconstruction of doses connected with Chernobyl accident need additional investigation. (Author)
This study examines the effectiveness of the laser-assisted new attachment procedure (LANAP) as measured by tooth loss, comparing data to published studies using conventional surgical treatment modalities for the primary treatment of Types III and IV periodontitis. Retrospective data from 107 patients presenting with Types III and IV periodontitis were gathered and evaluated. All patients received LANAP periodontal therapy as their primary surgical treatment according to the FDA-cleared LANAP protocol. The patients averaged 6.2 years post-treatment. The data were compared to several published studies for outcome classification and tooth loss over time. The effectiveness of LANAP as a primary treatment method for Types III and IV periodontitis compares very favorably with conventional surgical treatment modalities concerning tooth loss and stability over time, need for surgical retreatment, and outcome classification. Dentistry continues to develop less invasive means of providing patient care without sacrificing results. Less invasive treatment of periodontitis, with reduced postoperative morbidity yet equal results in tooth retention over time is an important goal. LANAP treatment for moderate and advanced periodontitis provides a less invasive treatment alternative for the dentist and patient to consider as a part of informed consent. PMID:22414508
Tilt, Lloyd V
This pamphlet discusses strategies for reducing baby bottle tooth decay (BBTD) among Native American children. BBTD in infants and toddlers is a painful disease characterized by extensive decay of the upper front and side teeth. It is caused by prolonged exposure of teeth to carbohydrates, such as those contained in infant formula, milk, and fruit…
Southeastern Regional Vision for Education (SERVE), Tallahassee, FL.
... nerves in the feet, legs, and hands. The gene mutations that cause Charcot-Marie-Tooth disease affect the function of ... CMT2J); GDAP1 (CMT2K); and HSPB8 (CMT2L). Certain DNM2 gene mutations also cause a form of CMT2. CMT4 is caused by ...
The author looks at Charcot-Marie-Tooth disease and the disabling effects that it can have on the patient. A course of action is outlined to help the patient cope more fully with this fairly common but little understood disorder.
Abstract Currently, localized pulpalgia is listed as a rare manifestation of chemotherapy treatments in patients with malignant tumors. The neuropathy originated from neurotoxicity of anticancer drugs is usually described as a diffuse jaw pain or numbness in orofacial structures. This article reports localized tooth pain as a possible outcome of administrating high dosage chemotherapy drugs particularly in the last cycles of application.
Maryam Kuzekanani; Jahangir Haghani
Currently, localized pulpalgia is listed as a rare manifestation of chemotherapy treatments in patients with malignant tumors. The neuropathy originated from neurotoxicity of anticancer drugs is usually described as a diffuse jaw pain or numbness in orofacial structures. This article reports localized tooth pain as a possible outcome of administrating high dosage chemotherapy drugs particularly in the last cycles of application. PMID:25628837
Kuzekanani, Maryam; Haghani, Jahangir
I am presenting an interesting case report of an ectopic eruption of teeth into left nasal cavity. Discussion is focused on clinical, radiological presentation, probable etiology, diagnosis, management and complications.Tooth inside nasal cavity is a rare form of supernumerary teeth which can be identified by performing CTscan.
Full Text Available I am presenting an interesting case report of an ectopic eruption of teeth into left nasal cavity. Discussion is focused on clinical, radiological presentation, probable etiology, diagnosis, management and complications.Tooth inside nasal cavity is a rare form of supernumerary teeth which can be identified by performing CTscan.
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.
Liu, Guanglei; Fan, Hongwei
Full Text Available SciELO Brazil | Language: English Abstract in english Tooth loss continues to be a prevalent condition in Brazilian adults and elderly individuals. The aim of this cross-sectional study, conducted among workers in a wholesale grocery chain in the State of São Paulo, was to identify risk indicators for tooth loss in adults. The presence of caries and pe [...] riodontal status were examined in 387 adults aged 20-64 years, according to World Health Organization criteria. Two outcomes were analyzed: loss of one or more teeth, and loss of four or more teeth. Independent variables analyzed were demographic and socioeconomic factors, clinical conditions, use of dental services, and self-perceived oral health. Poisson regression models were used for multivariate statistical analysis. Participants were missing a mean of 5.38 teeth, and 76.9% (n = 297) had lost at least one tooth; the most frequently lost teeth were permanent molars. Older age and the presence of visible dental biofilm were associated significantly with the two tooth loss outcomes (p
Marília Jesus, Batista; Lílian Berta, Rihs; Maria da Luz Rosário de, Sousa.
Surgical treatments of the impacted canine tooth were carried out in 8 young dogs, and the results were successful in 12 out of 14 cases (85.7%). The treatments consisting of surgical correction by immediate tipping movement, fenestration of the gingiva, and removal of the impacted tooth, were applied to 14 cases radiographically showing the immature tooth root and no abnormalities in the tooth root or alveolar bone. Impacted teeth were seen in 8 regions of the maxilla and 6 regions of the mandible. Mesioversion was seen in almost all maxillary impacted teeth, while linguoversion or lingual mesioversion in all mandibular cases. Surgical correction was carried out by immediate tipping movement after removal of the retained deciduous canine with or without resection of the alveolar bone. Fixation of the moved teeth was done using a wedge made from the deciduous canine root, which was driven into the vacant alveolar cavity after moving. An additional fixation using a steel wire and/or self-curing resin was done, if necessary
The analyses of the pattern of dental disease in the Late Medieval Serbian population from cemetery excavations in the archaeological site Grachanica were based on the study of tooth wear, ante-mortem tooth loss, caries, hypoplasia, alveolar resorption, abscesses and calculus. The total sample of all available skeletons with almost complete permanent dentition numbers 45 individuals. Dental sample comprises 178 maxillary teeth and 337 mandibular teeth. The presence of dental caries was scored taking into consideration the size of the lesion (four degrees) and its position on the tooth. The degree of tooth wear was graded into one of four categories: atrition of enamel only; atrition involving dentin; atrition up to the level of fissure at the occlusal surface of the molar teeth, and exposure of the pulp chamber. The cystic defects within the alveolar bone were recorded according to their aetiology, size and position. Radiographic study had not been done in order to detect periapical destruction, so the presence of such destruction was recognizable in advanced stages associated with the appearance of fistula penetrating the compact alveolar bone usually at the buccal side. The condition of the alveolar crest resorption, as the evidence of periodontal disease, was graded into three categories, and the distance from the cemento-enamel junction to the alveolar crest was measured. The analysis of dental pathology profile consisted of the two reporting methods: individual count method (prevalence of disease based on the number of individuals affected) and tooth count method (distribution of lesions frequency on tooth type and class). The Grachanica dentition exhibits a dental pathology profile typical of agricultural medieval populations in this region. Tooth wear was the most frequent, affecting 95% of individuals. Dental caries and ante-mortem teeth loss exhibit also high frequency (51% and 69%). Dental pains of low prevalence include abscesses (13%) and enamel hypoplasia (20%). In the material examined, the carious process was responsible for pulp exposure to infection in all cases of abscess formation. The results obtained suggest that food processing technology and nature of diet allowed use of abrasive in the food and that oral hygiene was at the low level. On the other hand, there were not a lot of people who were subjected to stress-induced growth disruptures. The findings reported here contribute to understand how dietary change and life conditions are related to the changing patterns of dental diseases in medieval populations. PMID:9921015
Djuri?-Sreji?, M; Stefanovi?, S
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...
Vadeboncoeur, Christian; Trahan, Luc
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.
Doliodus problematicus is the oldest known fossil shark-like fish with an almost intact dentition (Emsian, Lower Devonian, c. 397Ma). We provide a detailed description of the teeth and dentition in D. problematicus, based on tomographic analysis of NBMG 10127 (New Brunswick Museum, Canada). Comparisons with modern shark dentitions suggest that Doliodus was a ram-feeding predator with a dentition adapted to seizing and disabling prey. Doliodus provides several clues about the early evolution of the "shark-like" dentition in chondrichthyans and also raises new questions about the evolution of oral teeth in jawed vertebrates. As in modern sharks, teeth in Doliodus were replaced in a linguo-labial sequence within tooth families at fixed positions along the jaws (12-14 tooth families per jaw quadrant in NBMG 10127). Doliodus teeth were replaced much more slowly than in modern sharks. Nevertheless, its tooth formation was apparently as highly organized as in modern elasmobranchs, in which future tooth positions are indicated by synchronized expression of shh at fixed loci within the dental epithelium. Comparable dental arrays are absent in osteichthyans, placoderms, and many "acanthodians"; a "shark-like" dentition, therefore, may be a synapomorphy of chondrichthyans and gnathostomes such as Ptomacanthus. The upper anterior teeth in Doliodus were not attached to the palatoquadrates, but were instead supported by the ethmoid region of the prechordal basicranium, as in some other Paleozoic taxa (e.g., Triodus, Ptomacanthus). This suggests that the chondrichthyan dental lamina was originally associated with prechordal basicranial cartilage as well as jaw cartilage, and that the modern elasmobranch condition (in which the oral dentition is confined to the jaws) is phylogenetically advanced. Thus, oral tooth development in modern elasmobranchs does not provide a complete developmental model for chondrichthyans or gnathostomes. PMID:24347366
Maisey, John G; Turner, Susan; Naylor, Gavin J P; Miller, Randall F
Robots are increasingly performing human work as manufacturing is automated. Accordingly, the use of precision speed reducers has become essential for achieving precise control of the robot arm position. Curved tooth profiles, such as cycloid or involute tooth profiles, are generally used in precision speed reducers. Speed reducers with cycloid tooth profiles, which enable high precision control, are widely used to manipulate robot systems. This study proposes a speed reducer that has a trapezoidal tooth profile with straight lines. In this work, we mechanically analyzed trapezoidal tooth profiles, and then measured performance was by various tests using a prototype manufactured specifically for this study.
Nam, Won Ki; Oh, Se Hoon [Chung-Ang University, Seoul (Korea, Republic of)
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...
Muttagi, S.; Subramanya, J. K.
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.
Tooth enamel is a very brittle material; however it has the ability to sustain cracks without suffering catastrophic failure throughout the lifetime of mechanical function. We propose that the nanostructure of enamel can play a significant role in defining its unique mechanical properties. Accordingly we analyzed the nanostructure and chemical composition of a group of teeth, and correlated it with the crack resistance of the same teeth. Here we show how the dimensions of apatite nanocrystals in enamel can affect its resistance to crack propagation. We conclude that the aspect ratio of apatite nanocrystals in enamel determines its resistance to crack propagation. According to this finding, we proposed a new model based on the Hall-Petch theory that accurately predicts crack propagation in enamel. Our new biomechanical model of enamel is the first model that can successfully explain the observed variations in the behavior of crack propagation of tooth enamel among different humans. PMID:24813507
Ghadimi, Elnaz; Eimar, Hazem; Song, Jun; Marelli, Benedetto; Ciobanu, Ovidiu; Abdallah, Mohamed-Nur; Stähli, Christoph; Nazhat, Showan N; Vali, Hojatollah; Tamimi, Faleh
Anterior crown fractures are the most common type of injury in dental trauma. The ideal treatment is to reattach the fragments as quickly as possible following intraoral and radiographic examination, but sometimes delayed treatment appointments are necessary because of uninformed patients/parents or multidisciplinary cases included endodontically and periodontically. Delayed reattachment may lead to unesthetic results because of the dehydration of fragments. The purpose of this study was to present 1-year follow-ups of reattachment of dehydrated fragments using dentin bondings and flowable composites in two different cases. The color of the dehydrated fragments was natural in the control appointments and 1-year follow-ups show harmonious integration of color, form and texture after the reattachment of the original piece of tooth. Restoration of the tooth by reattaching the original fragment is the best way of treatment in esthetic, conservative and economic point of view. PMID:25511360
Bozkurt, F O; Demir, B; Erkan, E
The evidence concerning the management of shortened dental arch (SDA) cases is sparse. This multi-center study was aimed at generating data on outcomes and survival rates for two common treatments, removable dental prostheses (RDP) for molar replacement or no replacement (SDA). The hypothesis was that the treatments lead to different incidences of tooth loss. We included 215 patients with complete molar loss in one jaw. Molars were either replaced by RDP or not replaced, according to the SDA concept. First tooth loss after treatment was the primary outcome measure. This event occurred in 13 patients in the RDP group and nine patients in the SDA group. The respective Kaplan-Meier survival rates at 38 months were 0.83 (95% CI: 0.74-0.91) in the RDP group and 0.86 (95% CI: 0.78-0.95) in the SDA group, the difference being non-significant. PMID:20400723
Walter, M H; Weber, A; Marré, B; Gitt, I; Gerss, J; Hannak, W; Hartmann, S; Heydecke, G; Huppertz, J; Jahn, F; Ludwig, A; Mundt, T; Kern, M; Klein, V; Pospiech, P; Stumbaum, M; Wolfart, S; Wöstmann, B; Busche, E; Böning, K; Luthardt, R G
Full Text Available A dental implant is an artificial tooth that replaces a tooth that has been taken out. Implants are natural-looking, can provide support for dentures and do not affect the teeth bordering them. They are as stable as your real teeth and protect you from the loss of jawbone, which occurs when you lose teeth. Endosseous dental implants have revolutionized the fields of implants and periodontics. During the last decade, a great deal of information has been generated concerning the effectiveness and predictability of endosseous implants. Implant placement is a viable option in the treatment of partial and full edentulism and has become an integral facet of periodontal therapy. The available implants are remarkably successful. This review discusses the different aspects of dental implant including its advantages over the contemporary removable implants, its procedure in detail and the financial outlook of the same. The review also has a small consideration on minidental implant.
Evidence of prehistoric dentistry has been limited to a few cases, the most ancient dating back to the Neolithic. Here we report a 6500-year-old human mandible from Slovenia whose left canine crown bears the traces of a filling with beeswax. The use of different analytical techniques, including synchrotron radiation computed micro-tomography (micro-CT), Accelerator Mass Spectrometry (AMS) radiocarbon dating, Infrared (IR) Spectroscopy and Scanning Electron Microscopy (SEM), has shown that the exposed area of dentine resulting from occlusal wear and the upper part of a vertical crack affecting enamel and dentin tissues were filled with beeswax shortly before or after the individual's death. If the filling was done when the person was still alive, the intervention was likely aimed to relieve tooth sensitivity derived from either exposed dentine and/or the pain resulting from chewing on a cracked tooth: this would provide the earliest known direct evidence of therapeutic-palliative dental filling. PMID:23028670
Bernardini, Federico; Tuniz, Claudio; Coppa, Alfredo; Mancini, Lucia; Dreossi, Diego; Eichert, Diane; Turco, Gianluca; Biasotto, Matteo; Terrasi, Filippo; De Cesare, Nicola; Hua, Quan; Levchenko, Vladimir
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.
This article focuses on the cavovarus foot shape, with particular emphasis on those patients who have Charcot-Marie-Tooth disease. Recent greater understanding of this deformity has led to a better appreciation of how the underlying condition drives deformity progression and treatment of the problems associated with it. The basic science underpinning the development of Charcot-Marie-Tooth disease is reviewed and some elements of the importance of the genetic variability are emphasized. The mechanics of the development of the cavovarus foot deformity in patients who have this neuromuscular condition are reviewed and the evaluation of such patients is described. The surgical options for treatment are reviewed and the outcomes of studies relevant to surgical planning for this patient population are summarized. PMID:18457773
Beals, Timothy C; Nickisch, Florian
The use an excimer laser produced many unusual conical structures within the dentin of the inner part of the human tooth. By varying the frequency of the laser one can disperse the energy and cause more bleeding in laser surgery, but not destroy the cells associated with the incision. Therefore, the healing process will virtually be without scarring. Whereas, using the infrared laser the blood loss would be less, but the healing process would tend to be longer because cells are being destroyed due to the cauterization effect of the laser. The question is, are these structures produced as an interaction with the laser or are they an intrinsic part of the structure. The effects of the laser interaction upon dentin was studied, and in using electron microscopy the interaction of the excimer laser upon the tooth dentin and other various biological tissue is more clearly understood.
Hammond, Ernest C., Jr.; Gilliam, Ruth L.; Baker, George R.
In the framework of a comparison between three laboratories, electron paramagnetic resonance (EPR) signal-to-dose response curves were measured for sets of 30 tooth enamel samples and the variance of EPR measurements in dependence on absorbed dose was evaluated, in nine combinations of laboratory of sample preparation and EPR evaluation, respectively. As a test for benchmarking of EPR evaluation, the parameters 'critical dose' and 'limit of detection' were proposed as performance parameters following definitions from chemical-metrology, and a model function was suggested for analytical formulation of the dependence of the variance of EPR measurement on absorbed dose. First estimates of limits of detection by weighted and unweighted fitting resulted in the range 101-552 and 67-561 mGy, respectively, and were generally larger with weighted than with unweighted fitting. Indication was found for the influence of methodology of sample preparation and applied EPR measurement parameters on performance of EPR dosimetry with tooth enamel
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.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 Friedreich 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.
Charles Peter Tilbery
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...
Bajaj, Devendra; Arola, Dwayne
Several authors suggest that dolphins use information obtained by eavesdropping on echoes from sonar signals of conspecifics, but there is little evidence that this strategy is used by dolphins in the wild. Travelling rough-toothed dolphins (Steno bredanensis) either exhibit asynchronous movements or an extremely synchronized swimming behaviour in tight formations, which we expect to facilitate eavesdropping. Therefore, we determined, whether either one or more dolphins were echolocating in s...
Go?tz, Thomas; Verfuß, Ursula Katharina; Schnitzler, Hans-ulrich
Stain removal from teeth is important both to prevent decay and for appearance. This is usually achieved using a filament based toothbrush with a toothpaste consisting of abrasive particles in a carrier fluid. This work has been carried out to examine how these abrasive particles interact with the filaments and cause material removal from a stain layer on the surface of a tooth. It is important to understand this mechanism as while maximum cleaning efficiency is required, this must not be ...
Lewis, R.; Barber, S. C.; Dwyer-joyce, R. S.
Mesenchymal stem cell-mediated tissue regeneration is a promising approach for regenerative medicine for a wide range of applications. Here we report a new population of stem cells isolated from the root apical papilla of human teeth (SCAP, stem cells from apical papilla). Using a minipig model, we transplanted both human SCAP and periodontal ligament stem cells (PDLSCs) to generate a root/periodontal complex capable of supporting a porcelain crown, resulting in normal tooth function. This wo...
Sonoyama, Wataru; Liu, Yi; Fang, Dianji; Yamaza, Takayoshi; Seo, Byoung-moo; Zhang, Chunmei; Liu, He; Gronthos, Stan; Wang, Cun-yu; Shi, Songtao; Wang, Songlin
The diploma thesis entitled Tooth and mouth cavity care of preschool children consists of two parts: theoretical and empirical. The theoretical part introduces mouth cavity and its elements: development of teeth, their structure and arrangement, groups of teeth, dental tissues, saliva, tongue and dental plaques. We have found out that caries in Slovenia has been decreasing in the last couple of years. The thesis also presents taking care of teeth, especially the method of how to clean them, w...
Abstract The evidence concerning the management of shortened dental arch (SDA) cases is sparse. This multi-center study was aimed at generating data on outcomes and survival rates for two common treatments, removable dental prostheses (RDP) for molar replacement or no replacement (SDA). The hypothesis was that the treatments lead to different incidences of tooth loss. We included 215 patients with complete molar loss in one jaw. Molars were either replaced by RDP or no...
Walter, M. H.; Weber, A.; Marre?, B.; Gitt, I.; Gerß, J.; Hannak, W.; Hartmann, S.; Heydecke, G.; Huppertz, J.; Jahn, F.; Ludwig, A.; Mundt, T.; Kern, M.; Klein, V.; Pospiech, P.
Vascular reflexes were assessed in 17 adult patients with Charcot-Marie-Tooth disease using the Valsalva manoeuvre, and the pulse rate and systolic blood pressure responses to standing. Six patients showed abnormalities consistent with an autonomic neuropathy. One patient had giant nerve fibre bundles in the myenteric plexus of bowel resected for co-existent Crohn's disease, indicating histological involvement of these autonomic neurones. Other evidence of an autonomic component to the periph...
Brooks, A. P.
Charcot-Marie-Tooth disease (CMT) is a common inherited disorder of the peripheral nervous system characterised by distal weakness and muscular atrophy, sensory disturbance of the distal limbs, diminished or absent deep tendon reflexes and often pes cavus. CMT is divided into two major groups based on clinical and electrophysiological findings. CMT I is characterised by demyelination and markedly reduced nerve conduction velocity, whereas in CMT2 there is an axonal neuropath...
Pellicle rapidly accumulates on tooth surfaces after prophylaxis and may acquire cosmetically unacceptable levels of stain. A three-month clinical trial was conducted to evaluate stain prevention by a new silica-based tartar control whitening dentifrice (Crest Extra Whitening) compared to marketed tartar control baking soda peroxide whitening and regular dentifrice controls. Prior to the trial, a one-month screening exercise was conducted to identify adult subjects who accumulated extrinsic tooth stain after dental prophylaxis. A total of 672 subjects were stratified based on tooth whiteness, gender and tobacco usage, then given a dental prophylaxis and randomized into one of three dentifrice treatment groups. All product use was unsupervised. Change in tooth whiteness (delta L*) was determined by comparing colorimeter measurements collected on the facial surfaces of the four central incisors at months 1 and 3 to baseline. Ninety-six percent of subjects completed the three-month study. At both one and three months, the two whitening dentifrices did not differ from baseline in terms of delta L*. In contrast, the regular control had delta L* values of -0.26 and -0.39 at one and three months, respectively, differing significantly from baseline at both time points. Each of the whitening dentifrices differed statistically from the regular control in stain accumulation (p < or = 0.001) at one and three months, but were not different from each other. In general, all three test dentifrices were well tolerated. These data demonstrate the effectiveness of the new tartar control whitening dentifrice in preventing stain accumulation after dental prophylaxis compared to the marketed regular dentifrice control. PMID:11476015
Isaacs, R L; Bartizek, R D; Owens, T S; Walters, P A; Gerlach, R W
Full Text Available Abstract Currently, localized pulpalgia is listed as a rare manifestation of chemotherapy treatments in patients with malignant tumors. The neuropathy originated from neurotoxicity of anticancer drugs is usually described as a diffuse jaw pain or numbness in orofacial structures. This article reports localized tooth pain as a possible outcome of administrating high dosage chemotherapy drugs particularly in the last cycles of application.
Supernumerary teeth are defined as any supplementary tooth in addition to usual configuration of twenty deciduous and thirty-two permanent teeth. They are most commonly found in the anterior maxilla and mandibular bicuspid region. Although supernumerary teeth have been reported in the incisor region of the mandible, they are very rare. It has been confirmed that approximately 25% of permanent supernumerary teeth appear in the mouth, the rest remains unerupted. The aim of this study was ...
Grga ?urica; Dželetovi? Bojan
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 ne...
Thosre Deepika; Mulay Sanjyot
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...
Hong-Wen He; Fang Huang,; Jie Liu,
It is common practice to 'reinforce' the endodontically treated tooth with a post-and-core combination (either custom or prefabricated) and ultimately restore it with a crown. Many studies have looked at the post, treatment of the post surface, the cements and other factors. It appears that, regardless of the treatment of the post surface, current post cementing technology enables the practitioner to achieve higher retention than previously possible. PMID:2085159
Nathanson, D; Ashayeri, N
Tooth agenesis is the most common developmental dental anomaly. Absence of one or two permanent teeth is found in the majority of affected subjects. Very few patients suffer severe tooth agenesis. Recent studies revealed that WNT10A gene mutations caused syndromic and isolated severe tooth agenesis. In this study, to determine the contribution of WNT10A variants in different severities of tooth agenesis, we investigated the association between WNT10A variants and non-syndromic tooth agenesis in a Chinese population consisting of 505 tooth agenesis patients and 451 normal controls. Twenty-three novel non-synonymous variants were identified. WNT10A variants were detected in 15.8 % (75/474) of patients with 1-3 missing teeth and 51.6 % (16/31) of patients with 4 or more missing teeth. As compared with a frequency of 3.1 % in individuals with full dentition, variant allele frequencies were significantly elevated in both groups with tooth agenesis (p values of 1.00 × 10(-6) and 3.89 × 10(-23), respectively). Our findings showed that WNT10A variants were associated with non-syndromic tooth agenesis from mild to severe tooth agenesis, and the more severe tooth agenesis, the stronger association. Biallelic genotypes of WNT10A variants may have a pathogenic effect on tooth development. Presence of a single variant allele would be predisposing for causation with low penetrance. Together with WNT10A variant, there should be other genetic or environmental factors leading to biallelic variant-related variable clinical manifestations and single allele variant-related low penetrance. The frequent missing tooth positions in the WNT10A-related cases were consistent with that in the general population, suggesting WNT10A plays a critically important role in the etiology of general tooth agenesis. PMID:24043634
Song, Shujuan; Zhao, Ruiying; He, Huiying; Zhang, Jin; Feng, Hailan; Lin, Liyun
The purpose of this study was to evaluate the prevalence and distribution according to the types of tooth shape anomalies in permanent teeth of 6,082 persons by means of analysis of the full mouth periapical radiographs. And the following results were obtained ; 1. Among tooth shape anomalies, the highest incidence was observed on dilaceration (20.14%), followed by dens invaginatus (3.02%), peg lateralis (1.48%), taurodontism (0.34%), dens evaginatus (0.33%), talon cusp (0.20%), fusion (0.07%) and gemination (0%) in descending order of frequency. 2. Peg lateralis, dens invaginatus and dilaceration occurred more prevalent in females, and other types of tooth shape anomalies occurred more prevalent in males. 3. Dens evaginatus and taurodontism occurred with bilateral tendency, but other anomalies occurred with unilateral tendency. 4. As to the involved teeth, maxillary lateral incisors were the most frequently involved teeth on peg lateralis, dens invaginatus and talon cusp. And the mandibular premolars were the most frequently involved teeth on dens evaginatus, the maxillary first molars were on taurodontism, the maxillary second premolars were on dilaceration, and the mandibular incisors and canines were on fusion.
Choi, Karp Shik [Dept. of Oral Radiology, College of Dentistry, Kyungpook National University, Daegu (Korea, Republic of)
The purpose of this study was to evaluate the prevalence and distribution according to the types of tooth shape anomalies in permanent teeth of 6,082 persons by means of analysis of the full mouth periapical radiographs. And the following results were obtained ; 1. Among tooth shape anomalies, the highest incidence was observed on dilaceration (20.14%), followed by dens invaginatus (3.02%), peg lateralis (1.48%), taurodontism (0.34%), dens evaginatus (0.33%), talon cusp (0.20%), fusion (0.07%) and gemination (0%) in descending order of frequency. 2. Peg lateralis, dens invaginatus and dilaceration occurred more prevalent in females, and other types of tooth shape anomalies occurred more prevalent in males. 3. Dens evaginatus and taurodontism occurred with bilateral tendency, but other anomalies occurred with unilateral tendency. 4. As to the involved teeth, maxillary lateral incisors were the most frequently involved teeth on peg lateralis, dens invaginatus and talon cusp. And the mandibular premolars were the most frequently involved teeth on dens evaginatus, the maxillary first molars were on taurodontism, the maxillary second premolars were on dilaceration, and the mandibular incisors and canines were on fusion.
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.
Dawson, Andreas; Ljunggren, Lennart
After (extensive) loss of tooth tissue, vital teeth can be built up completely with composite restoration material. Sometimes, the application of additional retentive preparations is indicated. In exceptional cases, a root canal treatment is indicated, following which a root canal post is applied if necessary. Endodontically treated multi-rooted teeth can be built up entirely with composite, utilizing the pulp chamber and root canal accesses for retention. However, in single-rooted teeth a root canal post is necessary, in which case a prefabricated root post is used. Traditionally, metal posts were used in combination with a cast, indirect build-up restoration. Subsequently, directly fabricated cores, combining metal posts with amalgam or, at the present time, composite restoration material, became customary. The present trend is to use prefabricated or individually fabricated fibre-reinforced posts. After restoring a tooth with a build-up restoration, a combined build-up restoration can be chosen, or a direct or indirect crown single tooth prosthesis. PMID:23495567
Fokkinga, W A; Fennis, W M M; Witter, D J; Kreulen, C M; Creugers, N H J
Orthodontic biomechanics started in the early 1960s with the work of Burstone and later Nikolai. Experimental and theoretical studies using finite element methods (FEM) focused on the determination of the position of the center of resistance of single and multi-rooted teeth. Due to the complex structure of the system tooth/periodontal ligament/alveolar bone and because of the limited power of computers, the first numerical models were quite simple. Improved FE software, sophisticated programs for model generation and the explosion of computer power in the last decade resulted in more complex tooth-periodontium models and model assumptions. This paper describes the application of finite element methods in orthodontic biomechanics with the help of several typical examples. The examples cover aspects from basic orthodontic biomechanics to possible future applications in treatment planning using bone remodelling theories: determination of the mechanical properties of the periodontal ligament in a combined numerical and experimental study, calculation of the centers of resistance of different teeth, and simulation of orthodontic tooth movements. The examples show that nowadays finite element methods are a useful and easy-to-handle tool for the solution of a larger number of structure-mechanical and biomechanical problems. Nevertheless, in spite of the enormous technical progress in the last decade, many problems in orthodontic biomechanics remain to be solved. PMID:17455766
Bourauel, C; Keilig, L; Rahimi, A; Reimann, S; Ziegler, A; Jäger, A
Damage to tooth root surfaces may occur during ultrasonic cleaning with both piezoelectric and magnetostrictive ultrasonic scalers. It is unclear which mechanism causes more damage or how their mechanism of action leads to such damage. Our null hypothesis is that tooth-surface defect dimensions, resulting from instrumentation with ultrasonic scalers, are independent of whether the scaler probe is magnetostrictive or piezoelectric. Piezoelectric and magnetostrictive ultrasonic scaler probes were placed into contact against polished dentin samples (100 g/200 g). Resulting tooth surfaces were evaluated with a laser metrology system. Ultrasonic instrumentation produced an indentation directly related to the bodily movement of the probe as it made an impact on the surface. Load, generator power, and probe cross-section significantly affected probe vibration and defect depth/volume. Defect dimensions were independent of generator type. Magnetostrictive probes oscillated with greater displacement amplitudes than piezoelectric probes, but produced similar defects. This may be due to the cross-sectional shape of the probes. PMID:19329455
Lea, S C; Felver, B; Landini, G; Walmsley, A D
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.
Marc Daniel Grynpas
This study evaluated the effect of tooth-preparation cleansing protocols on the bond strength of a self-adhesive resin cement to dentin contaminated with two different types of hemostatic agents. The occlusal surface of extracted third molars was flattened to expose the dentin surface and prepared for a full crown. Acrylic temporary crowns were fabricated and placed using temporary cement. The specimens were stored at 100% relative humidity for seven days. Following removal of the temporary crowns, the specimens were surface debrided using aluminum oxide abrasion with a particle size of 27 ?m at 40 psi. The specimens were randomly assigned to three groups, according to the hemostatic agents: Group I–an agent containing aluminum chloride was applied to the tooth surface; Group II–an agent containing ferric sulfate was applied to the tooth surface and Group III–uncontaminated (control). The contaminated specimens were then further subdivided into three subgroups (A–C; n=12): Group A–tooth surface cleansing with water spray; Group B–tooth surface cleansing with phosphoric acid etch and Group C–tooth surface cleansing with aluminum oxide abrasion with a particle size of 27 ?m at 40 psi. Ceramic blocks were treated with a 9.5% hydrofluoric acid-etch and silanized prior to being cemented with self-adhesive resin luting agent (RelyX Unicem) to the prepared dentin. The shear bond strength was determined at a crosshead speed of 0.5 mm/minute. The data were analyzed with two-way ANOVA, followed by the Duncan multiple range test, to determine any significant differences between the testing groups. The microstructure morphology of the tooth surface was evaluated using SEM analysis. The results revealed that there was a significant difference between the bond strength of the control and the contaminated testing groups (ptooth preparation cleansing protocol using particle abrasion with low-pressure aluminum oxide particles provided a significant improvement in bond strength to contaminated dentin, while rinsing with water spray resulted in the lowest mean bond strength of the self-adhesive resin cement to dentin (p<0.05). PMID:21488725
Chaiyabutr, Y; Kois, J C
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.
Double tooth and talon cusp are tooth shape anomalies with rare co-occurrences in a single tooth. Double tooth is a developmental anomaly that leads to the eruption of fused teeth and may contribute to compromised esthetics, pain, caries, and tooth crowding. Talon cusp is a rare developmental extra cusp-like projection on the cingulum area that may cause functional and esthetic problems. Differential diagnosis of these anomalies may be complicated. A multidisciplinary approach for the esthetic and functional rehabilitation of double teeth is important. Various treatment methods have been described in the literature for the different types and morphological variations of double teeth. The purpose of this paper is to report the case of an unusual combination of double tooth and talon cusp on a permanent maxillary incisor and describe its esthetic and functional rehabilitation using a porcelain laminate veneer. PMID:25514262
Cordeiro, Wayne José Batista; do Couto, Cintia Fernandes; Barros, Renata Nunes; Zarranz, Laila; Jorge, Mônica Zacharias; de Gouvêa, Cresus Vínicius Depes
The aim of the present study was to evaluate the antimicrobial effect of antimicrobial photodynamic therapy (aPDT) in alveolar treatment of areas with induced periodontitis. Thirty male Wistar rats were subjected to ligature-induced periodontal disease (PD) in the first left inferior molars, while the right side molars did not receive ligatures. After 7 days of PD evolution, ligatures were removed from the left side, and the first left and right mandibular molars were extracted. Afterwards, animals were divided into groups according to the following treatments: control (C)-no treatment; mechanical debridement (MD)-mechanical debridement and irrigation with saline solution; and aPDT-mechanical debridement, irrigation with toluidine blue O (TBO), and 1 min of laser irradiation (GaAlAs, 660 nm, 30 mW, 32 J/cm(2), 60 s). Ligatures were removed and samples of the alveolar content after extraction and after each treatment were collected for microbial processing by real-time polymerase chain reaction with specific primers for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola. Data were submitted to statistical analysis by multiple comparison tests (McNemar test; p?effective antimicrobial treatment for tooth sockets in areas affected by induced periodontitis. PMID:23912780
Theodoro, Leticia Helena; Pires, Juliana Rico; Fernandes, Leandro Araújo; Gualberto Júnior, Erivan Clementino; Longo, Mariéllen; de Almeida, Juliano Milanezi; Garcia, Valdir Gouveia
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...
Imaizumi, Yuri; Amano, Ikuko; Tsuruga, Eichi; Kojima, Hiroshi; Sawa, Yoshihiko
Molar tooth structures are abundant in large (1-2 m diameter) carbonate nodules within fine-grained, subtidal carbonates of the early Neoproterozoic (lower Upper Riphean) Burovaya Formation along the Sukhaya Tunguska River, Turukhansk Uplift, northwestern Siberia. Although molar tooth structures are regionally abundant in this unit, here they occur only within the nodules. Stable isotopic compositions of molar-tooth-filling dolomicrospar cements and of thinly bedded dolomicrite within and sur...
Knoll, Andrew; Pope, Michael C.; Bartley, Julie K.; Petrov, Peter Yu
The author reports his experience on Refsum's disease and that gained after personally examining in detail 64 patients with Charcot-Marie-Tooth disease over the past ten years. The "cerebellar" inco-ordination in Charcot-Marie-Tooth disease (with or without distal wasting) and in Refsum's disease is analysed. Some variations in the motor and sensory neuropathy of Charcot-Marie-Tooth disease and Refsum's disease are discussed. The adequacy of motor conduction velocity in genetically distinguis...
Introduction: The most commonly used materials for prosthetic denture base are acrylic resins - polymethyl methacrylate, which has all the important physical and chemical properties. The bond between a denture base and an acrylic tooth has a significant functional value. Aim: To evaluate the influence of various procedures on bonding quality between the denture base and the artificial tooth, the measurement of gaps when connecting the tooth and the denture base using an optical or electron mi...
Pavlin Martin; Jerolimov Vjekoslav; Rudolf Rebeka; Stamenkovi? Dragoslav; Anžel Ivan
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, especi...
Li, Xiao; Venugopalan, Shankar R.; Cao, Huojun; Pinho, Flavia O.; Paine, Michael L.; Snead, Malcolm L.; Semina, Elena V.; Amendt, Brad A.
Introduction: Following orthognathic surgery, increased tooth mobility is observed clinically and is utilized for postsurgical orthodontic tooth movement. It was suggested that the increase may result from a surgery-associated alteration of parathyroid hormone (PTH) and calcium metabolism. Materials and Methods: 30 young adult patients were divided into a mandibular osteotomy group (Group A, n = 20) and an untreated control group (Group B, n = 10). Tooth mobility was evaluated using the Perio...
Nezar Watted; Emad Hussein; Muhamad Abu-Mowais; Azzaldeen Abdulgani; Peter Proff; Abu-Hussein Muhamad
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)
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.
Full Text Available Abstract Background The choice between several treatment options for replacing a single missing tooth is influenced by clinical, dentist- and patient-immanent factors. This study aimed to determine the patient factors that would affect the treatment decision to replace a single missing tooth and to assess the satisfaction with several options. Method 200 volunteers involved (121 females and 79 males divided into four groups, Group A: consisted of patients with conventional fixed partial dentures or patients with resin bonded fixed partial dentures. Group B: consisted of patients who received removable partial dentures while Group C: consisted of patients who received a single implant supported crown, and a control group D: consisted of patients who received no treatment. Data were collected using a questionnaire. Results The highest percentage of males within groups (58% was within the removable prostheses category. The majority of the subjects in the study reported that the main reason for replacing a missing tooth was for esthetic and function. Most important factor affecting the choice between treatment modalities was damaging the neighboring teeth. Pain, post operative sensitivity and dental phobia were important factors in choosing the prosthesis type and affected the control group patients not to have any treatment. The highest satisfaction percentage among groups studied was recorded for dental implants then FPD groups, while the least percentage were in both the control and RPD groups, for all aspects of function, esthetic and speech efficiency. Conclusions The final choice between FPD, RPD and implant depended on several factors which affected the decision making; among these is cost and patients' awareness of the different treatment options.
Al-Quran Firas A
Dental health care and research workers require a means of imaging the structures within teeth in vivo. For example, there is a need to image the margins of a restoration for the detection of poor bonding or voids between the restorative material and the dentin. With conventional x-ray techniques, it is difficult to detect cracks and to visualize interfaces between hard media. This due to the x-ray providing only a 2 dimensional projection of the internal structure (i.e. a silhouette). In addition, a high resolution imaging modality is needed to detect tooth decay in its early stages. If decay can be detected early enough, the process can be monitored and interventional procedures, such as fluoride washes and controlled diet, can be initiated which can help the tooth to re-mineralize itself. Currently employed x-ray imaging is incapable of detecting decay at a stage early enough to avoid invasive cavity preparation followed by a restoration with a synthetic material. Other clinical applications include the visualization of periodontal defects, the localization of intraosseous lesions, and determining the degree of osseointegration between a dental implant and the surrounding bone. A means of assessing the internal structure of the tooth based upon use of high frequency, highly localized ultrasound (acoustic waves) generated by a laser pulse is discussed. Optical interferometric detection of ultrasound provides a complementary technique with a very small detection footprint. Initial results using laser-based ultrasound for assessment of dental structures are presented. Discussion will center on the adaptability of this technique to clinical applications.
Blodgett, David W.; Baldwin, Kevin C.
It is hypothesized that wear of enamel is sensitive to the presence of sharp particulates in oral fluids and masticated foods. To this end, a generic model for predicting wear rates in brittle materials is developed, with specific application to tooth enamel. Wear is assumed to result from an accumulation of elastic-plastic micro-asperity events. Integration over all such events leads to a wear rate relation analogous to Archard?s law, but with allowance for variation in asperity angle and compliance. The coefficient K in this relation quantifies the wear severity, with an arbitrary distinction between 'mild' wear (low K) and 'severe' wear (high K). Data from the literature and in-house wear-test experiments on enamel specimens in lubricant media (water, oil) with and without sharp third-body particulates (silica, diamond) are used to validate the model. Measured wear rates can vary over several orders of magnitude, depending on contact asperity conditions, accounting for the occurrence of severe enamel removal in some human patients (bruxing). Expressions for the depth removal rate and number of cycles to wear down occlusal enamel in the low-crowned tooth forms of some mammals are derived, with tooth size and enamel thickness as key variables. The role of 'hard' versus 'soft' food diets in determining evolutionary paths in different hominin species is briefly considered. A feature of the model is that it does not require recourse to specific material removal mechanisms, although processes involving microplastic extrusion and microcrack coalescence are indicated. PMID:24953823
Borrero-Lopez, Oscar; Pajares, Antonia; Constantino, Paul J; Lawn, Brian R
The purpose of this study was to evaluate the prevalence and distribution of tooth number anomaly by means of the analysis of panoramic radiographs in 6,531 patients visited the Dental Infirmary of Kyungpook National University Hospital from January 1983 to May 1992 . The results were as follows : 1. The prevalence of congenitally missing teeth except third molar was revealed to be 10.8%, and there was a higher prevalence in females (44.6%) than in males (55.4%). Mandibular 2nd premolars (23.2%), and maxillary second primolars (15.4%) in descending order of frequency. As to the number of congentally missing teeth, the percentage of missing one tooth was 48%, missing two teeth was 35.4%, missing three teeth was 6.6%. 2. The prevalence of congenitally missing third molars was revealed to be 39.7%. There was a higher prevalence in the maxilla (60.3%) than in the mandible (39.7%). Maxillary right 3rd molars (30.6%) were absent most frequently, followed by maxillary left 3rd molar (29.7%), mandibular right 3rd molar (20.2%), mandibular left 3rd molar (19.5%) in descending order of frequency. 3. The prevalence of supernumerary teeth was revealed to be 4.2%, and there was a higher prevalence in the males (65.7%) than in females (34.3%). They were found most frequently in maxillary central incesor area (64.8%), followed by maxillary lateral incisor area (13.2%), posterior area of maxillary third molar (8.7%) in descending order of frequency. As to the number of supernumerary quency. As to the number of supernumerary teeth; the percentage of one supernumerary tooth was 79.9%, two supernumarary teeth was 8.9%, three supernumerary teeth was 1.2%.
The purpose of this study was to evaluate the prevalence and distribution of tooth number anomaly by means of the analysis of panoramic radiographs in 6,531 patients visited the Dental Infirmary of Kyungpook National University Hospital from January 1983 to May 1992 . The results were as follows : 1. The prevalence of congenitally missing teeth except third molar was revealed to be 10.8%, and there was a higher prevalence in females (44.6%) than in males (55.4%). Mandibular 2nd premolars (23.2%), and maxillary second primolars (15.4%) in descending order of frequency. As to the number of congentally missing teeth, the percentage of missing one tooth was 48%, missing two teeth was 35.4%, missing three teeth was 6.6%. 2. The prevalence of congenitally missing third molars was revealed to be 39.7%. There was a higher prevalence in the maxilla (60.3%) than in the mandible (39.7%). Maxillary right 3rd molars (30.6%) were absent most frequently, followed by maxillary left 3rd molar (29.7%), mandibular right 3rd molar (20.2%), mandibular left 3rd molar (19.5%) in descending order of frequency. 3. The prevalence of supernumerary teeth was revealed to be 4.2%, and there was a higher prevalence in the males (65.7%) than in females (34.3%). They were found most frequently in maxillary central incesor area (64.8%), followed by maxillary lateral incisor area (13.2%), posterior area of maxillary third molar (8.7%) in descending order of frequency. As to the number of supernumerary teeth; the percentage of one supernumerary tooth was 79.9%, two supernumarary teeth was 8.9%, three supernumerary teeth was 1.2%.
Park, Sang Eok; Choi, Karp Shik [Dept. of Oral Radiology, College of Dentistry, Kyungpook National University, Daegu (Korea, Republic of)
Ion microprobe U-Pb dating of apatite is applied to a fossil tooth of a Allosaurid derived from the Hasandong Formation in the Gyeongsang basin, southeastern Korea. Twelve spots on a single fragment of the fossil dentine yield a Tera-Wasserburg concordia intercept age of 115±10 Ma (2?, MSWD=0.59) on a 238U/206Pb-207Pb/206Pb-204Pb/206Pb diagram. The age provides a constraint on the depositional age of the fossil in its host Hassandong Formation as Early Aptian. The success of the ion microprobe dating depends on the heterogeneities of diagenetically incorporated U and Pb at the few hundred ?m scale, the consequent variations in Pb isotopic compositions due to radioactive decay and the closed-system behavior of U and Pb. There are at least three end-members to explain the variations of minor chemical components such as FeO, SiO2 and Al2O3, and trace elements as Th, U and rare earth elements (REE) in the sample by a simple mixing model. They are (1) very low minor and REE, very high common Pb with variable U abundances, (2) low common Pb, high minor, REE, and U abundances, and (3) low minor, common Pb, and U with intermediate REE abundances, even though groups (2) and (3) may consist of a larger group. Various contributions of the three (and/or two) end-members during diagenetic processes may cause the elemental fractionation of U and Pb in a fossil tooth. (author)nd Pb in a fossil tooth. (author)
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.
Gear, C W; Kevrekidis, Yu G; Li, Ju; Kevrekidis, Ioannis G.
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
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...
Lee, Jung-hwa; Choi, Byung-ok
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 %
Full Text Available The paper presents the results of numerical analyses of the rotary compression process for hollow stepped shafts with herringbone teeth. The numerical simulations were performed by Finite Element Method (FEM, using commercial software package DEFORM-3D. The results of numerical modelling aimed at determining the effect of billet wall thickness on product shape and the rotary compression process are presented. The distributions of strains, temperatures, damage criterion and force parameters of the process determined in the simulations are given, too. The numerical results obtained confirm the possibility of producing hollow toothed shafts from tube billet by rotary compression methods.
While orthodontic tooth movement (OTM) gains considerable popularity and clinical success, the roles played by relevant tissues involved, particularly periodontal ligament (PDL), remain an open question in biomechanics. This paper develops a soft-tissue induced external (surface) remodeling procedure in a form of power law formulation by correlating time-dependent simulation in silico with clinical data in vivo (pprocedure. This algorithm was found rather indicative and effective to simulate OTM under different loading conditions, which is of considerable potential to predict therapeutical outcomes and develop a surgical plan for sophisticated orthodontic treatment. PMID:24703301
Chen, Junning; Li, Wei; Swain, Michael V; Ali Darendeliler, M; Li, Qing
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.
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.
Win, Htet Htet Ne
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.
Win, Htet Htet Ne
An oblique incidence interferometer for measuring a non-optical surface of a gear tooth with a phase shifting method is developed. The incidence angle of a He-Ne laser is set to be 84.75 degree(s) with a wedge prism, to obtain fringe spacing corresponding to the height of 3.64 micrometers . The reference beam is piezo-electrically modulated to make phase shifting fringe analysis. A high resolution CCD camera with resolution of 1280 X 1024 is used so that about 200 fringes can be analyzed. The maximum deviation of about 420 micrometers from a plane reference surface is measured with an accuracy of 40 nm.
Ino, Tomomi; Yatagai, Toyohiko
The integument forms a number of different types of mineralized element, including dermal denticles, scutes, ganoid scales, elasmoid scales, fin rays and osteoderms found in certain fish, reptiles, amphibians and xenarthran mammals. To this list can be added teeth, which are far more widely represented and studied than any of the other mineralized elements mentioned above, and as such can be thought of as a model mineralized system. In recent years the focus for studies on tooth development has been the mouse, with a wealth of genetic information accrued and the availability of cutting edge techniques. It is the mouse dentition that this review will concentrate on. The development of the tooth will be followed, looking at what controls the shape of the tooth and how signals from the mesenchyme and epithelium interact to lead to formation of a molar or incisor. The number of teeth generated will then be investigated, looking at how tooth germ number can be reduced or increased by apoptosis, fusion of tooth germs, creation of new tooth germs, and the generation of additional teeth from existing tooth germs. The development of mineralized tissue will then be detailed, looking at how the asymmetrical deposition of enamel is controlled in the mouse incisor. The continued importance of epithelial-mesenchymal interactions at these later stages of tooth development will also be discussed. Tooth anomalies and human disorders have been well covered by recent reviews, therefore in this paper we wish to present a classical review of current knowledge of tooth development, fitting together data from a large number of recent research papers to draw general conclusions about tooth development. PMID:19422427
Catón, Javier; Tucker, Abigail S
Acute trauma or trauma associated with occlusal disharmony can produce tooth crack or fracture. Although several methods are proposed to treat the defect, however, the prognosis is generally poor. If the fusion of a tooth fracture by laser is possible it will offer an alternative to extraction or at least serve as an adjunctive treatment in the reconstruction. The responses of soft tissues to lasers of different wavelengths are fairly well known, but the reactions of hard tissues are still to be understood. The purpose of this research was to study the feasibility of using a medium energy continuous-wave CO(2) laser and a low melting-point bioactive glass to fuse or bridge tooth fractures. The present report is focused on the first part of the research, the analysis of changes in laser-irradiated human tooth enamel/dentin by means of X-ray diffractometer (XRD), Fourier-transforming infrared spectroscopy (FTIR), differential thermal analysis/thermogravimetric analysis (DTA/TGA), and scanning electron microscopy (SEM). After CO(2) laser irradiation, there were no marked changes in the X-ray diffraction pattern of the enamel when compared to that before laser treatment. However, a small peak belonging to alpha-TCP appeared at the position of 2theta=30.78 degrees C. After being treated with CO(2) laser, the dentin showed much sharper peaks on the diffraction patterns because of grain growth and better crystallinity. alpha-TCP and beta-TCP were identified after laser treatment. In the FTIR analysis, an HPO(4)(-2) absorption band was noted before laser treatment disappeared after the irradiation. No significant change in the absorption band of HPO(4)(-2) was found on the FTIR curves of enamel after laser treatment. The results of DTA/TGA indicated that loss of water and organic materials occurred in both enamel and dentin after laser treatment. Under SEM, melting and resolidification occurred in both enamel and dentin by medium energy of CO(2) laser. This implies that using a continuous-wave CO(2) laser of medium energy density to fuse a low melting-point bioactive glass to the enamel/dentin is possible. We believe these phase changes and thermal data can make a useful guide for future studies on the thermal interaction and bridging mechanism between the bioactive glass and enamel/dentin under CO(2) laser irradiation. PMID:15348019
Lin, C P; Lee, B S; Kok, S H; Lan, W H; Tseng, Y C; Lin, F H
The clinical and electrophysiologic profiles of two brothers suffering from Charcot-Marie-Tooth disease are presented. Both had widespread muscle twitching in the legs which showed electrophysiologic features of myokymia. Pedigree analysis suggested an x-linked recessive form of inheritance. This appears to be the first report of an Indian family with x-linked Charcot-Marie-Tooth disease.
Chakravarty A; Ghosh B; Sengupta S; Mukhopadhyay S
The aim of this article is to discuss relevant considerations about crown bonding and describe a clinical case in which a tooth fragment and direct composite resin were used to successfully restore a fractured anterior tooth. Clinical examinations showed good esthetics and periodontal health after 10 years of follow-up. PMID:24892464
Reston, E G; Reichert, L A; Busato, A L Stefanello; Bueno, R P R; Zettermann, J
Coexistent partial anodontia and supernumerary tooth in the lower jaw is a very uncommon condition. Very few cases have been reported in the literature of this condition, etiology of which is still obscure. Presented here is a rare case of simultaneous presence of single supernumerary tooth together with missing permanent central incisor teeth in the lower jaw without any associated systemic condition or syndrome.
Das G; Sarkar Subir; Bhattacharya B; Saha N
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.
Giovani de Oliveira Correa
Full Text Available Charcot-Marie-Tooth hereditary motor and sensory neuropathy refers to a group of disorders characterized by a chronic motor and sensory polyneuropathy. Typical cases have distal muscle weakness and peroneal atrophy often associated with mild to moderate sensory loss, depressed tendon reflexes, and pes cavus. Hereditary neuropathies are categorized by mode of inheritance and chromosomal locus. The diagnosis is based on family history, characteristic findings on physical examination, EMG, nerve conduction velocity testing, and occasionally on nerve biopsy. The disorder shows allelic and non-allelic genetic heterogeneity, thus mutations of different genes leading to the same clinical features. Also, different mutations of the same gene may lead to different phenotypes. Molecular genetic testing is available in clinical laboratories for diagnosis of 7 subtypes of the disease. Genetic counseling and risk assessment depend on the inheritance. We present two cases with Charcot-Marie-Tooth type 1 and type 2 respectively. There is no cure for the disorder, although physical therapy and moderate activity are often recommended to maintain muscle strength and endurance.
An ultrasound contact imaging method is proposed to measure the enamel thickness in the human tooth. A delay-line transducer with a working frequency of 15 MHz is chosen to achieve a minimum resolvable distance of 400 ?m in human enamel. To confirm the contact between the tooth and the transducer, a verification technique based on the phase shift upon reflection is used. Because of the high attenuation in human teeth, linear frequency-modulated chirp excitation and pulse compression are exploited to increase the penetration depth and improve the SNR. Preliminary measurements show that the enamel-dentin boundary creates numerous internal reflections, which cause the applied chirp signals to interfere arbitrarily. In this work, the fractional Fourier transform (FrFT) is employed for the first time in dental imaging to separate chirp signals overlapping in both time and frequency domains. The overlapped chirps are compressed using the FrFT and matched filter techniques. Micro-computed tomography is used for validation of the ultrasound measurements for both techniques. For a human molar, the thickness of the enamel layer is measured with an average error of 5.5% after compressing with the FrFT and 13.4% after compressing with the matched filter based on the average speed of sound in human teeth. PMID:21989873
Harput, Sevan; Evans, Tony; Bubb, Nigel; Freear, Steven
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
Christen, Arden G; Christen, Joan A
The growth of the crown and root in the canine tooth of beagle dogs were observed macroscopically and radiographically, and changes of occlusion with age were investigated. Completion of growth in the crown of the canine tooth was observed in both mandible and maxilla, and its eruption was accompanied by development of the dental root. The permanent canine erupted on the lingual side of deciduous canine in the mandible, and on the mesial side of the deciduous canine in the maxilla. Movement of the permanent canine to normal occlusal position(buccal direction in mandibular canine, and distal direction in maxillary canine)was followed by the loss of the deciduous canine. Coexistence of the permanent and deciduous canines occurred for about 2.4 weeks in the maxilla and about 1.4 weeks in the mandible, on average. Macroscopically, the growth of the permanent canine was completed by 33 weeks of age in the mandible and about 34 weeks of age in the maxilla. The mature root of the permanent canine was recognized radiographically at about 43 weeks of age in the mandible and 47 weeks of age in the maxilla
The outer part of shark teeth is formed by the hard and mineral-rich enameloid that has excellent mechanical properties, which makes it a very interesting model system for the development of new bio-inspired dental materials. We characterized the microstructure, chemical composition and resulting local mechanical properties of the enameloid from teeth of Isurus oxyrinchus (shortfin mako shark) by performing an in-depth analysis using various high-resolution analytical techniques, including scanning electron microscopy, qualitative energy-dispersive X-ray spectroscopy and nanoindentation. Shark tooth enameloid reveals an intricate hierarchical arrangement of thin (50-80nm) and long (>1?m) crystallites of fluoroapatite with a high degree of structural anisotropy, which leads to exceptional mechanical properties. Both stiffness and hardness are surprisingly homogeneous in the shiny layer as well as in the enameloid: although both tooth phases differ in structure and composition, they show almost no orientation dependence with respect to the loading direction of the enameloid crystallites. The results were used to determine the structural hierarchy of shark teeth, which can be used as a base for establishing design criteria for synthetic bio-inspired and biomimetic dental composites. PMID:24797528
Enax, Joachim; Janus, Anna M; Raabe, Dierk; Epple, Matthias; Fabritius, Helge-Otto
Molecular genetic research on Charcot-Marie-Tooth 1 syndrome (CMT 1) progresses rapidly, still obviously no cure is available for affected individuals. Our aim was to investigate current management in clinical CMT 1 50 patients with Charcot-Marie-Tooth syndrome type I (CMT 1) were explored for applied means of therapy and use of health care institutions. We documented the number of annual appointments at a neurologist, orthopaedist and psychologist. Previous admissions to hospitals and rehabilitation centres and surgical procedures were assessed. Practice of physiotherapy, occupational and physical therapy were investigated, also administered orthopaedic devices, mechanical devices and technical modification of car and home. Drugs prescribed were listed and the number of patients seeking advice at para-medical institutions was determined. Degree of medical support did not correlate with severity of disease. We observed that persons with marked disability did not uniformly receive adequate therapy. This was partly due to the responsible physicians, and partly due to lacking cooperation of the patients. Support of affected individuals and counselling to our opinion are to be improved. This would require further evaluation of therapies, establishment and distribution of guidelines, as well as motivation of patients, which might be facilitated by the offer of molecular genetic diagnostics. PMID:9273468
Wicklein, E M; Pfeiffer, G; Ratusinski, T; Kunze, K
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
Mostowska, Adrianna; Zadurska, Ma?gorzata; Rakowska, Adriana; Lianeri, Margarita; Jagodzi?ski, Pawe? P
Discolouration of teeth, especially the anteriores, can result in considerably cosmetic impairment in person. Combine effects of intrinsic and extrinsic colour determines the appearance of teeth. Whitening of teeth with bleaching is a more conservative therapeutic method than full crowns, veneers or composite restorations which is more invasive and expensive. Among bleaching techniques, in office bleaching with carbamide peroxide provide superior aesthetic result in short period of time with no adverse effects. This paper presents case series of tooth discolouration in non-vital tooth which was successfully bleached using 35 % carbamide peroxide. After 1 year follow up the prognosis was good with no reversal of tooth discolouration. This case report allows the better understanding of the concept of nonvital tooth bleaching with carbamide peroxide which gives a non-invasive alternative for aesthetic purpose in preserving the natural tooth structure. PMID:24551731
Badole, Gautam P; Warhadpande, Manjusha M; Bahadure, Rakesh N; Badole, Shital G
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.
Pedersen, Niels Leergaard
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.
Gao, Hui; Chae, Ok Sam [Kyung Hee University, Seoul (Korea, Republic of)
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.
Full Text Available Introduction: The presence of ectopic supernumerary tooth is not an uncommon fact, and the estimate is that 1% of the population is affected. However, a tooth in nasal cavity is a rare event, independently of the etiology. Objective: To report a case of a tooth in nasal cavity whose etiology is neither traumatic and nor iatrogenic. Case report: The young patient presented with a radiopaque image in nasal cavity during dental propedeutics. Upon otorhinolaryngological exams, a tooth was identified, in spite of no existence of any trauma. Surgical treatment was carried out without complications. Final Comments: The presence of tooth in nasal cavity, in spite of being uncommon, must be given special attention. The dangerous triangle of the face is a potential place of complications, therefore, the approach must be surgical even in asymptomatic patients.
Oliveira, Henrique Fernandes de
Tooth transplantation can be considered a valid and predictable treatment option for rehabilitating young patients with permanent teeth loss. This study presents several cases of successful autogenous tooth transplantation with a 6-9 months follow-up. Tooth auto-transplantation can be considered a reasonable option for replacing missing teeth when a donor tooth is available. The auto-transplantation of a right mandibular third molar with compromised function and esthetics to replace the residual roots resulting from coronal destruction due to extensive carious lesion of the second molar in the same quadrant as shown in the presented cases can result a viable treatment alternative especially in a young patient that cannot undergo dental implant therapy. Transplantation of mature third molar seems to be a promising method for replacing a lost permanent molar tooth and restoring esthetics and function. This clinical procedure showed excellent functional and esthetical long-term results in the analyzed cases. PMID:25540668
Nim?enko, Tatjana; Omerca, Gražvydas; Bramanti, Ennio; Cervino, Gabriele; Laino, Luigi; Cicciù, Marco
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...
Losey, Robert J.; Jessup, Erin; Nomokonova, Tatiana; Sablin, Mikhail
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.
Pordeus Isabela A
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.
Julie M. Kapp, PhD, MPH
The canonical (?-catenin dependent) Wnt signaling pathway has emerged as a likely candidate for regulating tooth replacement in continuously renewing dentitions. So far, the involvement of canonical Wnt signaling has been experimentally demonstrated predominantly in amniotes. These studies tend to show stimulation of tooth formation by activation of the Wnt pathway, and inhibition of tooth formation when blocking the pathway. Here, we report a strong and dynamic expression of the soluble Wnt inhibitor dickkopf1 (dkk1) in developing zebrafish (Danio rerio) tooth germs, suggesting an active repression of Wnt signaling during morphogenesis and cytodifferentiation of a tooth, and derepression of Wnt signaling during start of replacement tooth formation. To further analyse the role of Wnt signaling, we used different gain-of-function approaches. These yielded disjunct results, yet none of them indicating enhanced tooth replacement. Thus, masterblind (mbl) mutants, defective in axin1, mimic overexpression of Wnt, but display a normally patterned dentition in which teeth are replaced at the appropriate times and positions. Activating the pathway with LiCl had variable outcomes, either resulting in the absence, or the delayed formation, of first-generation teeth, or yielding a regular dentition with normal replacement, but no supernumerary teeth or accelerated tooth replacement. The failure so far to influence tooth replacement in the zebrafish by perturbing Wnt signaling is discussed in the light of (i) potential technical pitfalls related to dose- or time-dependency, (ii) the complexity of the canonical Wnt pathway, and (iii) species-specific differences in the nature and activity of pathway components. Finally, we emphasize the importance of in-depth knowledge of the wild-type pattern for reliable interpretations. It is hoped that our analysis can be inspiring to critically assess and elucidate the role of Wnt signaling in tooth development in polyphyodonts. PMID:25339911
Huysseune, Ann; Soenens, Mieke; Elderweirdt, Fien
The finite element (FE) analysis is an effective method to study the strength and predict the fracture risk of endodontically-treated teeth. This paper presents a rapid method developed to generate a comprehensive tooth FE model using data retrieved from micro-computed tomography (?CT). With this method, the inhomogeneity of material properties of teeth was included into the model without dividing the tooth model into different regions. The material properties of the tooth were assumed to be related to the mineral density. The fracture risk at different tooth portions was assessed for root canal treatments. The micro-CT images of a tooth were processed by a Matlab software programme and the CT numbers were retrieved. The tooth contours were obtained with thresholding segmentation using Amira. The inner and outer surfaces of the tooth were imported into Solidworks and a three-dimensional (3D) tooth model was constructed. An assembly of the tooth model with the periodontal ligament (PDL) layer and surrounding bone was imported into ABAQUS. The material properties of the tooth were calculated from the retrieved CT numbers via ABAQUS user's subroutines. Three root canal geometries (original and two enlargements) were investigated. The proposed method in this study can generate detailed 3D finite element models of a tooth with different root canal enlargements and filling materials, and would be very useful for the assessment of the fracture risk at different tooth portions after root canal treatments. PMID:22901677
Chen, G; Fan, W; Mishra, S; El-Atem, A; Schuetz, M A; Xiao, Y
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 p...
Kakoei S.; Fatemian M.; Eskandari Zadeh A.; Parirokh M.; Aa, Haghdoost
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)
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
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.
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. PMID:20660973
Baliga, M S; Bhat, S S
Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF2 conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF2 solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF2 for 5 min, rinsed in saline, immersed in 1% doxycycline HCl for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF2 solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis. PMID:1439522
Selvig, K A; Bjorvatn, K; Bogle, G C; Wikesjö, U M
Patient: Male, 27 Final Diagnosis: Recurrent epistaxis Symptoms: Nasal bleeding Medication: — Clinical Procedure: — Specialty: Pediatrics and Neonatology Objective: Congenital defects/diseases Background: Recurrent epistaxis is a common disorder among children and young adults. We report an unusual cause, intranasal supernumerary tooth causing friction with Little’s area of the nasal septum. Case Report: A 22-year-old male presented with recurrent, mild, unilateral left-sided epistaxis once to twice per month for 3 years. This usually occurred after minor nasal trauma or rubbing his nose. The patient also suffered from recurrent tonsillitis. There was neither history of blood transfusion or nasal packing, nor a history suggestive of bleeding diathesis. Anterior rhinoscopy revealed ivory white nasal mass antero-inferiorly in the left nasal cavity touching Little’s area. There was no bleeding. Nasal endoscopy showed a white cylindrical bony mass 1 cm long arising from the floor of the nose, with no attachment to the nasal septum or the lateral wall of the nose. Examination of the right nasal cavity was unremarkable. Conclusions: Nasal teeth result from the ectopic eruption of supernumerary teeth and may cause a variety of symptoms including recurrent epistaxis. Their clinical and radiologic presentation is so characteristic that their diagnosis is not difficult. CT scan is helpful in planning management. Early extraction prevents further complications and prevents further attacks of epistaxis. PMID:25031783
Al Dhafeeri, Hamed O.; Kavarodi, Abdulmajid; Shaikh, Khalil Al; Bukhari, Ahmed; Hussain, Omair Al; Baramawy, Ahmed El
Chemical action of bleaching agents applied to tooth surface is accelerated by increase in temperature. This in vitro study measured the temperature rises on the surface and in the pulp of teeth during whitening using a diode laser, a plasma arc curing (PAC) light and conventional curing lights. Extracted, non-carious single-rooted teeth were exposed to PAC light and laser at times ranging from 10 to 60 seconds and energy ranges of 2 W, 4 W, and 6 W, and to low-intensity curing lights from 1 to 4 minutes. Maximum temperature rises were analyzed for both pulpal and surface temperature. Diode laser exposures at 2 W for all times and at 4 watts for 10 seconds and PAC light exposures at 10 seconds all produced acceptably safe pulpal rises equivalent to conventional light-curing exposures. Exposures at these settings also attained surface temperature rises that were significantly higher than those using conventional light-curing. The diode laser demonstrated bleaching results equivalent to the PAC light, and both were achieved in significantly less times than conventional light- curing.
White, Joel M.; Pelino, Jose; Rodrigues, Rively; Zwhalen, Brian J.; Nguyen, Max H.; Wu, Emily
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.
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.
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?0.001). Median IA was 7.50 (2.60-30.70) in the PWS group and 2.60 (0.90-4.70) among controls (p?0.001). In the PWS group tooth wear correlated significantly with age (VEDE; r?=?0.79, p?0.001, IA; r?=?0.82, p?0.001) and saliva secretion (VEDE; r?=?0.46, p?=?0.001, IA; 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?0.001) and log IA (p?0.001). The only factor significantly associated with tooth wear in the control group was age. 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. PMID:22639910
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 a...
Da?ns?oreanu, Ioana Costina; Fildan, Floarea
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.
Ioana Costina DÂN?OREANU
Ahmet Günay,1 Osman Fatih Arpa?,2 Serhat Atilgan,3 Ferhan Yaman,3 Yusuf Atalay,4 ?zzet Acikan3 1Department of Periodontology, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 2Department of Periodontology, Faculty of Dentistry, Mustafa Kemal University, Hatay, Turkey; 3Department of Maxillofacial Surgery, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 4Department of Maxillofacial Surgery, Faculty of Dentistry, Kocatepe University, Afyon, Turkey Aim: The purpos...
Günay A; Of, Arpag?; Atilgan S; Yaman F; Atalay Y; Acikan I
Full Text Available This article provides a clinically grounded classification of degrees of atrophy of the bone the alveolar processes of jaws in accordance with specific strategies for dental implantation
Introduction. Dental treatment performed in patients receiving continuous oral anticoagulant drug therapy is becoming increasingly common in dental offices. For these patients it is imperative to carry out careful anamnesis, as well as a multiprofessional clinical evaluation with regard to the risk and control of hemorrhagic or thromboembolic episodes. Objectives and Material and Methods. The aim is to evaluate postextraction hemorrhagic or thromboembolic episodes in patients who have bee...
Amp Rmino Ant Amp Nio Souza, C.; Maria Elvira P. Corrêa; Danilo Santos Carneiro; Patrícia Freire Gasparetto; Pereira, Claudio Maranh Amp O.
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.
We are developing a framework for multiscale computation which enables models at a ``microscopic'' level of description, for example Lattice Boltzmann, Monte Carlo or Molecular Dynamics simulators, to perform modelling tasks at ``macroscopic'' length scales of interest. The plan is to use the microscopic rules restricted to small "patches" of the domain, the "teeth'', using interpolation to bridge the "gaps". Here we explore general boundary conditions coupling the widely separated ``teeth'' of the microscopic simulation that achieve high order accuracy over the macroscale. We present the simplest case when the microscopic simulator is the quintessential example of a partial differential equation. We argue that classic high-order interpolation of the macroscopic field provides the correct forcing in whatever boundary condition is required by the microsimulator. Such interpolation leads to Tooth Boundary Conditions which achieve arbitrarily high-order consistency. The high-order consistency is demonstrated on ...
Roberts, A J
The applicability of rapid and precise laser probe analysis of tooth enamel for ?18O has been verified, and the method has been applied to different modern herbivores in East Africa. Sampling and pretreatment procedures involve initial bleaching and grinding of enamel to 95% apatite) can be analyzed reliably. Different East African herbivores exhibit previously unsuspected compositional differences. Average enamel ?18O values (V-SMOW) are approximately: 25‰ (goat), 27‰ (oryx), 28‰ (dikdik and zebra), 29‰ (topi), 30‰ (gerenuk), and 32‰ (gazelle). These compositions differ from generalized theoretical models, but are broadly consistent with expected isotope effects associated with differences in how much each animal (a) drinks, (b) eats C3 vs. C4 plants, and (c) pants vs. sweats. Consideration of diet, water turnover, and animal physiology will allow the most accurate interpretation of ancient teeth and targeting of environmentally-sensitive animals in paleoclimate studies.
Kohn, Matthew J.; Schoeninger, Margaret J.; Valley, John W.
Several authors suggest that dolphins use information obtained by eavesdropping on echoes from sonar signals of conspecifics, but there is little evidence that this strategy is used by dolphins in the wild. Travelling rough-toothed dolphins (Steno bredanensis) either exhibit asynchronous movements or an extremely synchronized swimming behaviour in tight formations, which we expect to facilitate eavesdropping. Therefore, we determined, whether either one or more dolphins were echolocating in subgroups that were travelling with asynchronous and synchronized movements. Since, the number of recording sequences in which more than one animal produced sonar signals was significantly lower during synchronized travel, we conclude that the other members of a subgroup might get information on targets ahead by eavesdropping. Synchronized swimming in tight formations might be an energetic adaptation for travelling in a pelagic dolphin species that facilitates eavesdropping. PMID:17148311
Götz, Thomas; Verfuss, Ursula Katharina; Schnitzler, Hans-Ulrich
Full Text Available Charcot-Marie-Tooth disease (CMT is an inherited neuronal disorder, and is induced by mutations of various genes associated with intracellular membrane traffic and cytoskeleton. A large GTPase, dynamin, which is known as a fission protein for endocytic vesicles, was identified as a gene responsible for dominant-intermediate CMT type 2B (DI-CMT2B. Of these mutants, the PH domain, which is required for interaction with phosphoinositides, was mutated in several families. Interestingly, the expression of a deletion mutant, 551?3, did not impair endocytosis, but induced abnormal accumulation of microtubules. Recent evidence has shown that dynamin 2 regulates the dynamic instability of microtubules, and 551?3 lacks this function. We propose a model for the regulation of the dynamic instability of microtubules by dynamin 2 and discuss the relationship between dynamin 2 and CMT.
The proton-induced gamma emission (PIGE) is used for fluorine depth profiling in human tooth enamel after in vivo application of Duraphat lacquer. The time behaviour of the stored fluorine has been studied for 4 weeks after application up to a depth of 2.3 ?m. A significant increase of the fluorine amount is observed in this region. However, the in vitro-application gives a considerable higher fluorine amount. The range with a distinct gradient of the fluorine depth profile changes in the direction of the surface with increasing time. There is no significant difference between the fluorine profiles in the range of 600 nm up to 2.3 ?m. (author)
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.
Mônica Campos Serra
Immature permanent teeth damaged by caries or trauma can present a challenge to dentistry. Currently, triple antibiotic paste (TAP) containing ciprofloxacin, metronidazole, and minocycline is used to attempt revascularization in necrotic immature teeth. Therefore, the purpose of this report was to present a case of pulp revascularization in an immature necrotic tooth. An 8-year-old male presented with trauma to the permanent maxillary left and right central incisors. Upon clinical and radiographic examination, the left central incisor was deemed necrotic. Revascularization therapy was performed over multiple visits. At 11 months follow-up, healing of the periapical area and apexogenesis were found to be complete. With an increasing breadth of clinical evidence and practitioner acceptance, regenerative techniques may become a standard technique in treating immature necrotic permanent teeth. PMID:23265169
Gelman, Richard; Park, Helen
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.
Arthur-Farraj, P J
In the United States, composites accounted for nearly 70% of the 173.2 million composite and amalgam restorations placed in 2006 (Kingman et al., 2012), and it is likely that the use of composite will continue to increase as dentists phase out dental amalgam. This trend is not, however, without consequences. The failure rate of composite restorations is double that of amalgam (Ferracane, 2013). Composite restorations accumulate more biofilm, experience more secondary decay, and require more frequent replacement. In vivo biodegradation of the adhesive bond at the composite-tooth interface is a major contributor to the cascade of events leading to restoration failure. Binding by proteins, particularly gp340, from the salivary pellicle leads to biofilm attachment, which accelerates degradation of the interfacial bond and demineralization of the tooth by recruiting the pioneer bacterium Streptococcus mutans to the surface. Bacterial production of lactic acid lowers the pH of the oral microenvironment, erodes hydroxyapatite in enamel and dentin, and promotes hydrolysis of the adhesive. Secreted esterases further hydrolyze the adhesive polymer, exposing the soft underlying collagenous dentinal matrix and allowing further infiltration by the pathogenic biofilm. Manifold approaches are being pursued to increase the longevity of composite dental restorations based on the major contributing factors responsible for degradation. The key material and biological components and the interactions involved in the destructive processes, including recent advances in understanding the structural and molecular basis of biofilm recruitment, are described in this review. Innovative strategies to mitigate these pathogenic effects and slow deterioration are discussed. PMID:25190266
Spencer, P; Ye, Q; Misra, A; Goncalves, S E P; Laurence, J S
Most of the morphological features recognized in hominin teeth, particularly the topography of the occlusal surface, are generally interpreted as an evolutionary functional adaptation for mechanical food processing. In this respect, we can also expect that the general architecture of a tooth reflects a response to withstand the high stresses produced during masticatory loadings. Here we use an engineering approach, finite element analysis (FEA), with an advanced loading concept derived from individual occlusal wear information to evaluate whether some dental traits usually found in hominin and extant great ape molars, such as the trigonid crest, the entoconid-hypoconulid crest and the protostylid have important biomechanical implications. For this purpose, FEA was applied to 3D digital models of three Gorillagorilla lower second molars (M2) differing in wear stages. Our results show that in unworn and slightly worn M2s tensile stresses concentrate in the grooves of the occlusal surface. In such condition, the trigonid and the entoconid-hypoconulid crests act to reinforce the crown locally against stresses produced along the mesiodistal groove. Similarly, the protostylid is shaped like a buttress to suffer the high tensile stresses concentrated in the deep buccal groove. These dental traits are less functional in the worn M2, because tensile stresses decrease physiologically in the crown with progressing wear due to the enlargement of antagonistic contact areas and changes in loading direction from oblique to nearly parallel direction to the dental axis. This suggests that the wear process might have a crucial influence in the evolution and structural adaptation of molars enabling to endure bite stresses and reduce tooth failure throughout the lifetime of an individual. PMID:23894570
Benazzi, Stefano; Nguyen, Huynh Nhu; Kullmer, Ottmar; Hublin, Jean-Jacques
Geochemical inferences on ancient diet using bone and enamel apatite rely mainly on carbon isotope ratios (?(13)C) and to a lesser extent on strontium/calcium (Sr/Ca) and barium/calcium (Ba/Ca) elemental ratios. Recent developments in nontraditional stable isotopes provide an unprecedented opportunity to use additional paleodietary proxies to disentangle complex diets such as omnivory. Of particular relevance for paleodietary reconstruction are metals present in large quantity in bone and enamel apatite, providing that biologically mediated fractionation processes are constrained. Calcium isotope ratios (?(44)Ca) meet these criteria but exhibit complex ecological patterning. Stable magnesium isotope ratios (?(26)Mg) also meet these criteria but a comprehensive understanding of its variability awaits new isotopic data. Here, 11 extant mammal species of known ecology from a single locality in equatorial Africa were sampled for tooth enamel and, together with vegetation and feces, analyzed for ?(26)Mg, ?(13)C, Sr/Ca, and Ba/Ca ratios. The results demonstrate that ?(26)Mg incorporated in tooth enamel becomes heavier from strict herbivores to omnivores/faunivores. Using data from experimentally raised sheep, we suggest that this (26)Mg enrichment up the trophic chain is due to a (26)Mg enrichment in muscle relative to bone. Notably, it is possible to distinguish omnivores from herbivores, using ?(26)Mg coupled to Ba/Ca ratios. The potential effects of metabolic and dietary changes on the enamel ?(26)Mg composition remain to be explored but, in the future, multiproxy approaches would permit a substantial refinement of dietary behaviors or enable accurate trophic reconstruction despite specimen-limited sampling, as is often the case for fossil assemblages. PMID:25535375
Martin, Jeremy E; Vance, Derek; Balter, Vincent
Full Text Available AbstractIntroduction: Knowledge of prevalence and etiologic factors of tooth discoloration can help design strategies for intervention to prevent tooth discoloration. The aim of this study was to determine the prevalence and etiologic factors of tooth discoloration in male high school students in Isfahan.Materials and methods: In this cross-sectional study, 384 male students were selected by cluster sampling method. The students were examined by a well-instructed individual. Data was collected and recorded using a questionnaire and then analyzed by descriptive methods in SPSS at a 95% confidence interval.Results: The prevalence of tooth discoloration was 89.9% in male high school students in Isfahan. Relative frequencies of etiologic factors of tooth discoloration consisted of caries, 80.6%; hypoplasia, 18.2%; extrinsic stains, 9.5%; root and crown restorative materials, 4.8%; trauma, 1.3%; tetracycline and smoking, 0.8%; fluorosis, 0.5%; and chlorhexidine mouthwash, 0.3%. No cases of amelogenesis imperfecta, dentinogenesis imperfecta, and drug use by mothers during pregnancy. Conclusion: In this study caries was the most common cause of tooth discoloration. Given the high prevalence of carious lesions, instruction of oral hygiene habits and improving nutrition of the students are recommended. Key words: Etiologic factors, frequency, male students, Tooth discoloration.
Spatio-temporal immunolocalizations of cytokeratin 8 (CK8), vimentin, syndecan-1 and Ki-67 were analyzed in ten human incisors and canine tooth germs between the 7th and 20th developmental weeks. CK8 expression was mild to moderate in the epithelial tooth parts, while it shifted from absent or mild in its mesenchymal parts, but few cells, sparsely distributed throughout the tooth germ, strongly expressed CK8. As development progressed, CK8 expression increased to strong in preameloblasts, while expression of vimentin increased to moderate in the epithelial and mesenchymal tooth parts, particularly in the dental papilla and sac. Co-expression of CK8 and vimentin was observed in some parts of the tooth germ, and was increasing in the differentiating preameloblasts and preodontoblasts. Syndecan-1 showed characteristic shift of expression from epithelial to mesenchymal tooth parts, being particularly strong in dental papilla, sac and cervical loops, while co-expression of Ki-67/syndecan-1 was strong in the dental papilla. Our study demonstrated spatio-temporal expression and restricted co-expression of the investigated markers, indicating participation of CK8 and vimentin in cell proliferation and migration, and differentiation of preodontoblasts and preameloblasts. Our data also suggest involvement of syndecan-1 in morphogenesis of the developing tooth crown and cervical loops, and together with CK8 and vimentin in differentiation of preameloblasts and preodontoblasts. PMID:25120060
Kero, D; Kalibovic Govorko, D; Vukojevic, K; Cubela, M; Soljic, V; Saraga-Babic, M
While numerous genes that play important regulatory roles during tooth development in mice have been identified, little is known about gene expression profile and their function during human odontogenesis. To unveil expression profile of odontogenic genes in humans, we conducted genome-wide gene expression analysis by microarray assays to analyze differential gene expression between tooth germ and lip tissue from 11-week old human fetuses. We identified 167 genes that are strongly expressed in the cap stage tooth germ as compared to the lip tissue. Among them, 145 genes were further identified by gene ontology enrichment analysis that are highly represented in multiple gene ontology classes, include extracellular components, sequence-specific DNA binding proteins, Wnt-protein binding molecules, system development, organogenesis, and cell differentiation. Sixty-seven genes that are known to be associated with mammalian tooth development and tooth abnormalities were identified. Real-time PCR was further employed to validate microarray data. Moreover, in situ hybridization assay demonstrated tooth type specific expression of ISL1 and BARX1 in the incisor, canine, and molar respectively, consistent with microarray results. Our results represent a set of reliable data that could provide a solid base for future elaboration of molecular mechanisms underlying human tooth development. PMID:25092397
Huang, Zhen; Hu, Xuefeng; Lin, Chensheng; Chen, Suzhu; Huang, Feng; Zhang, Yanding
Full Text Available SciELO Brazil | Language: English Abstract in english 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.
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.
Full Text Available Introduction: Following orthognathic surgery, increased tooth mobility is observed clinically and is utilized for postsurgical orthodontic tooth movement. It was suggested that the increase may result from a surgery-associated alteration of parathyroid hormone (PTH and calcium metabolism. Materials and Methods: 30 young adult patients were divided into a mandibular osteotomy group (Group A, n = 20 and an untreated control group (Group B, n = 10. Tooth mobility was evaluated using the Periotest device. Tooth mobility, serum PTH and calcium levels were determined repeatedly for both groups. Results: The tooth mobility was increased significantly in the Group A patients in the first 10 days post-surgery. All serum PTH and calcium mean levels were within normal ranges. No significant differences were found between the measurements of both groups. The serum calcium levels recorded at the 1st post-surgery day were slightly lower in the operated patients compared to the control group. Conclusion: It can be concluded that the increased facility of orthodontic tooth movement immediately post-surgery was confirmed by Periotest measurements, while no association was found with surgery-related altered levels of PTH and calcium. Since dietary effects can be ruled out, the increase of clinical tooth mobility may rather result from preoperative orthodontic forces and/or the post-surgical elimination of masticatory muscular influences.
Developmental genetic studies of evolved differences in morphology have led to the hypothesis that cis-regulatory changes often underlie morphological evolution. However, because most of these studies focus on evolved loss of traits, the genetic architecture and possible association with cis-regulatory changes of gain traits are less understood. Here we show that a derived benthic freshwater stickleback population has evolved an approximate twofold gain in ventral pharyngeal tooth number compared with their ancestral marine counterparts. Comparing laboratory-reared developmental time courses of a low-toothed marine population and this high-toothed benthic population reveals that increases in tooth number and tooth plate area and decreases in tooth spacing arise at late juvenile stages. Genome-wide linkage mapping identifies largely separate sets of quantitative trait loci affecting different aspects of dental patterning. One large-effect quantitative trait locus controlling tooth number fine-maps to a genomic region containing an excellent candidate gene, Bone morphogenetic protein 6 (Bmp6). Stickleback Bmp6 is expressed in developing teeth, and no coding changes are found between the high- and low-toothed populations. However, quantitative allele-specific expression assays of Bmp6 in developing teeth in F1 hybrids show that cis-regulatory changes have elevated the relative expression level of the freshwater benthic Bmp6 allele at late, but not early, stages of stickleback development. Collectively, our data support a model where a late-acting cis-regulatory up-regulation of Bmp6 expression underlies a significant increase in tooth number in derived benthic sticklebacks. PMID:25205810
Cleves, Phillip A; Ellis, Nicholas A; Jimenez, Monica T; Nunez, Stephanie M; Schluter, Dolph; Kingsley, David M; Miller, Craig T
This in-vitro study analyzed the bleaching efficacy of various tooth whiteners for home use with a low concentration of active substances (carbamide peroxide=CP, sodium chlorite=SC, hydrogen peroxide=HP). To this end both the visual tooth shade determination and the computer-aided tooth shade determination (SpectroShade) was applied. At the same time the enamel of the specimen was examined for a change of the surface with the help of the Knoop microhardness measurements. After staining 288 an...
Beheim-schwarzbach, Nils Janning
Full Text Available Intrabony migration of impacted teeth is a rare developmental dental anomaly that occurs only in the permanent dentition of the lower jaw. A case report of migration of a second molar tooth to the ascending mandibular ramus is presented. A panoramic radiograph of a 32-year-old male revealed an unerupted second molar below the coronoid process on the left mandibular ramus. Since the patient refused to have the tooth removed, periodic radiographic observation will be conducted. Early detection by radiographic survey, along with timely removal of the unerupted tooth could prevent the development of such migration.
A 10 mo old Sapsaree dog presented for evaluation and treatment of malocclusion causing palatal trauma. A class III malocclusion with mesiolinguoversion of the 404 and enamel hypoplasia was diagnosed based on oral examination. It was decided to attempt orthodontic correction of the mesiolinguoverted tooth using an elastic chain and inclined bite plane technique with crown restoration of the enamel hypoplasia teeth. One year after the orthodontic correction and composite removal, the mesiolinguoverted right mandibular canine tooth was moved to an acceptable location within the dental arch and the locally discolored right maxillary canine tooth was vital. PMID:25415215
Kim, Chun-Geun; Lee, So-Young; Park, Hee-Myung
Full Text Available Objective: To present a case of Charcot Marie Tooth Disease. Backgrounds: A 22 years old boy presented with very slowly progressive symmetrical weakness of both lower limbs with distal muscular atrophy. He has a family member with similar problem. Methods: The patient was clinically examined and investigations done accordingly like Nerve Conduction Velocity studies (NCV. Results: The patient was diagnosed to be a case of Charcot Marie Tooth disease type 1 with classical features like” inverted Champagne bottle” like legs. Conclusion: Charcot Marie Tooth disease is rare and often undiagnosed yet it is the commonest hereditary neuropathy worldwide and India is not an exception
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. PMID:23649072
Kubasad, Girish; Ghivari, Sheetal; Garg, Khushboo
Full Text Available Fusion is a developmental anomaly defined as the union of two normally separated tooth buds or the partial splitting of one tooth bud into two buds. Depending on the stage of development, fusion may be either complete or incomplete.The significance of this particular case was that this fusion occurred in a posterior permanent mandibular tooth, while such a manifestation is more reported in maxillary anterior teeth; either in the primary (0.5% or permanent (0.1% dentition.The genetic basis for this anomaly is probably autosomal dominant with reduced penetrance. In addition, the essential findings for differential diagnosis include numberof teeth, radiography and clinical features.
Fusion is a developmental anomaly defined as the union of two normally separated tooth buds or the partial splitting of one tooth bud into two buds. Depending on the stage of development, fusion may be either complete or incomplete.The significance of this particular case was that this fusion occurred in a posterior permanent mandibular tooth, while such a manifestation is more reported in maxillary anterior teeth; either in the primary (0.5%) or permanent (0.1%) dentition.The genetic basis f...
Jb, Taheri; Baharvand, M.; Ar, Vahidi-ghahrodi
A new approach is proposed for the local synthesis of spiral bevel gears. The approach provides contact at the mean contact point with the desired deviation of the transmission error function by a predesigned parabolic function. The orientation of the contact path on the gear tooth surface and the length of the major axis of the instantaneous contact ellipse are also included in the analysis. A tooth contact analysis (TCA) computer program was developed to simulate meshing and contact of the gear tooth surfaces. A numerical example of the process is given.
Litvin, F. L.; Zhang, Y.; Handschuh, R. F.
Although acrylic resin teeth are the most popular artificial teeth used for denture construction, a high number fracture away at the tooth-denture base interface. Various causes have been documented for this failure; however, it is logical that eventual fracture occurs due to localised tensile stresses at this interface. Examination of these stresses using the finite element method showed that on load application to the upper incisors, the maximum tensile stresses were concentrated within the body of the tooth and not at the tooth-denture base interface. Stresses encountered at the interface were relatively low and introduction of a crack made no significant difference to their magnitude. PMID:8148790
Darbar, U R; Huggett, R; Harrison, A; Williams, K
Tooth stiffness is a very important parameter in studying both static and dynamic behaviour of spline couplings and gears. Many works concerning tooth stiffness calculation are available in the literature, but experimental results are very rare, above all considering spline couplings. In this work experimental values of spline coupling tooth stiffness have been obtained by means of a special hexapod measuring device. Experimental results have been compared with the corresponding theoretical and numerical ones. Also the effect of angular misalignments between hub and shaft has been investigated in the experimental planning.
Curà, Francesca; Mura, Andrea
Intrinsic discoloration of a non-vital permanent incisor tooth due to trauma may have a significant esthetic and social impact on children and adolescents. Treatment options for discolored Non-vital teeth are bleaching, crowns or veneers. However, this restorative crown or veneer approach has a significant drawback of being an invasive technique. Intervention should be minimal destruction of tooth structure and should not compromise future restorative options. The advantage bleaching over crown is that it offers simple conservative approach in removal of stain and whitening discolored teeth without damaging tooth structure. PMID:25097441
Patil, Anandkumar G; Hiremath, Vinaykumar; Kumar, R Sheetal; Sheetal, Aparna; Nagaral, Suresh
Between 1949 and 1951 about 100 PBq of intermediate and low level liquid radioactive wastes were released into the Techa River (Southern Urals, Russia). To estimate the radiation exposure of Techa River residents having taken place in the past, EPR measurements of tooth enamel were performed. The cumulative dose obtained by EPR, however, is due to both, external photons and internal 90Sr incorporated in enamel and dentin. To provide estimates of the 90Sr content in the teeth tissue, three supplementary methods are used: • visualization and mapping of the 90Sr distribution in tooth tissue using Imaging Plates. • measurements of the 90Sr activity in tooth tissue samples using a ?-spectrometer. • measurements of dose rate due to 90Sr in tooth samples using thin-layer Al2O3:C TL dosimeters.
The phylogenetic affinities of the extinct pseudo-toothed birds have remained controversial. Some authors noted that they resemble both pelicans and allies (Pelecaniformes) and tube-nosed birds (Procellariiformes), but assigned them to a distinct taxon, the Odontopterygiformes. In most recent studies, the pseudo-toothed birds are referred to the family Pelagornithidae inside the Pelecaniformes. Here, I perform a cladistic analysis with five taxa of the pseudo-toothed birds including two undescribed new species from the Early Tertiary of Morocco. The present hypothesis strongly supports a sister group relationship of pseudo-toothed birds (Odontopterygiformes) and waterfowls (Anseriformes). The Odontoanserae (Odontopterygiformes plus Anseriformes) are the sister group of Neoaves. The placement of the landfowls (Galliformes) as the sister taxon of all other neognathous birds does not support the consensus view that the Galloanserae (Galliformes plus Anseriformes) are monophyletic.
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.
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.
The aim of the present study was to investigate the effects of atmospheric pressure cold plasma with different gases on external tooth bleaching. After 10 min treatment, the air (50%) + oxygen (50%) group shows a remarkable color change (?E*), and nitrogen and air groups indicate some color change, although not as much as that shown by the air + oxygen group. Also, the argon group shows the least amount of color change among the various gases in this experiment. Atomic oxygen species exists during this tooth bleaching as determined by optical emission spectroscopy. Hence, atmospheric pressure cold plasma treatment could significantly accelerate the tooth bleaching process owing to this atomic oxygen species, and the intensity of tooth bleaching depends on the type of gas in the cold plasma.
Choi, Hye-sook; Kim, Kyoung-Nam; You, Eun-Mi; Choi, Eun-Ha; Kim, Yong-Hee; Kim, Kwang-Mahn
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.
Abstract Background The accessibility of the developing zebrafish pharyngeal dentition makes it an advantageous system in which to study many aspects of tooth development from early initiation to late morphogenesis. In mammals, hedgehog signaling is known to be essential for multiple stages of odontogenesis; however, potential roles for the pathway during initiation of tooth development or in later morphogenesis are incompletely understood. Results We have ident...
Stock David W; Yoo James J; Jackman William R
Tooth enamel is formed by epithelially-derived cells called ameloblasts, while the pulp dentin complex is formed by the dental mesenchyme. These tissues differentiate with reciprocal signaling interactions to form a mature tooth. In this study we have characterized ameloblast differentiation in human developing incisors, and have further investigated the role of extracellular matrix proteins on ameloblast differentiation. Histological and immunohistochemical analyses showed that in the human ...
He, Pingping; Zhang, Yan; Kim, Seong Oh; Radlanski, Ralf J.; Butcher, Kristin; Schneider, Richard A.; Denbesten, Pamela K.
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 tho...
Pordeus Isabela A; Oliveira Maria J; Martins Carolina C; Paiva Saul M
Intrabony migration of impacted teeth is a rare developmental dental anomaly that occurs only in the permanent dentition of the lower jaw. A case report of migration of a second molar tooth to the ascending mandibular ramus is presented. A panoramic radiograph of a 32-year-old male revealed an unerupted second molar below the coronoid process on the left mandibular ramus. Since the patient refused to have the tooth removed, periodic radiographic observation will be conducted. Early detection ...
Sermet ?ahin; Nuriye Sayg?n; Hasan Altu?
The need for new dental tissue-replacement therapies is evident in recent reports which reveal startling statistics regarding the high incidence of tooth decay and tooth loss. Recent advances in the identification and characterization of dental stem cells, and in dental tissue-engineering strategies, suggest that bioengineering approaches may successfully be used to regenerate dental tissues and whole teeth. Interest in dental tissue-regeneration applications continues to increase as clinical...
Abstract Background The saw-tooth sign was first described by Sanders et al in patients with obstructive sleep apnea syndrome as one cause of extrathoracic central airway obstruction. The mechanism of the saw-tooth sign has not been conclusively clarified. The sign has also been described in various extrathoracic central airway diseases, such as in burn victims with thermal injury to the upper airways, Parkinson’s disease, tracheobronchomalacia, laryngeal dyskinesia, and pe...
Nakajima Akira; Saraya Takeshi; Takata Saori; Ishii Haruyuki; Nakazato Yoko; Takei Hidefumi; Takizawa Hajime; Goto Hajime
This study explored ethnic differences in perceptions of pain and the need for local anesthesia for tooth drilling among age- and gender-matched Anglo-American, Mandarin Chinese, and Scandinavian dentists (n = 129) and adult patients (n = 396) using a systematic qualitative research strategy. Semistructured qualitative interviews determined: (a) the relative frequency of use or nonuse of anesthetic for similarly specified tooth drilling, (b) the reasons for nonuse of anesthetic as reported by...
Moore, R.; Bra?¸dsgaard, I.; Mao, T. K.; Miller, M. L.; Dworkin, S. F.
Full Text Available SciELO Brazil | Language: English Abstract in english 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.
Paulo Maurício Batista da, Silva; Emílio José Tabaré Rodríguez, Acosta; Matheus, Jacobina; Luciana de Rezende, Pinto; Vinícius Carvalho, Porto.
Computerised tomographic scanning was used to investigate tooth structure in chinchillas (Chinchilla laniger), both cheek tooth crown and root abnormalities being common in this species. This paper describes a common form of dental disease affecting species with continuously growing teeth, with particular reference to the chinchilla, and confirms the potential role of computed tomography (CT) in its early diagnosis. CT imaging is compared with previously available methods of investigation which frequently fail to detect early pathological changes
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
Dong, Xiuqing; Shen, Bin; Ruan, Ningsheng; Guan, Zhen; Zhang, Yanding; Chen, YiPing; Hu, Xuefeng
Objective: Tramadol is a synthetic analgesic of opioids which has more flexible mechanisms of action than typical opioids. Since it has been reported in previous study that typical opioids like morphine can affect the bone homeostasis, it is worthwhile to examine the effects of tramadol on tooth movement. In this study we investigated effects of tramadol on orthodontic tooth movement in rats.Materials and Methods: 30 male wistar rats were selected and received orthodontic appliance. 3 groups ...
Javadi, E.; Alaeddini, M.; Ar, Dehpour; Ahmad Akhoundi, M. S.; Noroozi, H.; Rashidpour, M.
Resorption is a pathologic process that often eludes the clinician with its varied etiologic factors and diverse clinical presentations. The key cells involved in tooth resorption are odontoclasts which are multinucleated cells that produce resorption lacunae. Resorption can be classified as internal and external resorption. Internal resorption has been described as a rare occurrence as compared to external resorption. This article describes the pathogenesis of tooth resorption and various fo...
Fernandes, Marina; Ataide, Ida; Wagle, Rahul
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...
Chen, Fu; Rice, Kelly C.; Liu, Xin-ming; Reinhardt, Richard A.; Bayles, Kenneth W.; Wang, Dong
Full Text Available The clinical and electrophysiologic profiles of two brothers suffering from Charcot-Marie-Tooth disease are presented. Both had widespread muscle twitching in the legs which showed electrophysiologic features of myokymia. Pedigree analysis suggested an x-linked recessive form of inheritance. This appears to be the first report of an Indian family with x-linked Charcot-Marie-Tooth disease.
Extant rhinos are the largest extant herbivores exhibiting dietary specialisations for both browse and grass. However, the adaptive value of the wear-induced tooth morphology in rhinos has not been widely studied, and data on individual cusp and tooth positions have rarely been published. We evaluated upper cheek dentition of browsing Diceros bicornis and Rhinoceros sondaicus, mixed-feeding R. unicornis and grazing Ceratotherium simum using an extended mesowear method adapted for rhinos. We i...
Taylor, Lucy A.; Kaiser, Thomas M.; Schwitzer, Christoph; Mu?ller, Dennis W. H.; Codron, Daryl; Clauss, Marcus; Schulz, Ellen
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 associ...
Mishra, Navin; Narang, Isha; Mittal, Neelam
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...
Shivashankar, Vasundara Yayathi; Johns, Dexton Antony; Vidyanath, S.; Kumar, M. Ramesh
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. PMID:24124320
Mishra, Navin; Narang, Isha; Mittal, Neelam
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 hydroxyapatitmilar 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
Full Text Available Coexistent partial anodontia and supernumerary tooth in the lower jaw is a very uncommon condition. Very few cases have been reported in the literature of this condition, etiology of which is still obscure. Presented here is a rare case of simultaneous presence of single supernumerary tooth together with missing permanent central incisor teeth in the lower jaw without any associated systemic condition or syndrome.
Fusion is the union of two tooth buds that are normally separated. Fusion is more frequent in deciduous teeth, particularly in the anterior region. The etiology of fusion is not known. It has been suggested that the pressure of adjacent dental follicles produces their contact and fusion before calcification. There is no difference between men and women in incidence. The term paradental cyst means that such type of cysts that are close proximity with the root of a tooth. A history of recurrent...
Prakash, A. Ravi; Reddy, P. Sreenivas; Rajanikanth, M.
Intrinsic discoloration of a non-vital permanent incisor tooth due to trauma may have a significant esthetic and social impact on children and adolescents. Treatment options for discolored Non-vital teeth are bleaching, crowns or veneers. However, this restorative crown or veneer approach has a significant drawback of being an invasive technique. Intervention should be minimal destruction of tooth structure and should not compromise future restorative options. The advantage bleaching over cro...
Patil, Anandkumar G.; Hiremath, Vinaykumar; Kumar, R. Sheetal; Sheetal, Aparna; Nagaral, Suresh
Statement of Problem: There are different tooth brushing methods for removing dental plaque from tooth surfaces. The effectiveness of these methods, and the time needed for instruction, learning and using seem to be different. Also, it is possible that the effectiveness of each method reduces with time, based on its difficulty level and the reduction of the patient s attention in following the given instructions. Purpose: The aim of this research was to compare the effectiveness of six differ...
Saghazadeh M; Pedodontist, Ashayeri N.
Full Text Available In this paper is presented a contact stress calculation algorithm for a new type of cylindrical toothed wheel. This new type consists in the application of a Xylan 1052 fluoropolymer film on the surface of a metal toothed wheel. Due to the fact that the steel strength, in any case is better than the plastic strength, the main issue which appears is at the contact between the two homologous flank surfaces.
Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.
Ildeu, Andrade Jr; Ana Beatriz dos Santos, Sousa; Gabriela Gonçalves da, Silva.
A method for generation of crowned pinion tooth surfaces using a surface of revolution is developed. The crowned pinion meshes with a regular involute gear and has a prescribed parabolic type of transmission errors when the gears operate in the aligned mode. When the gears are misaligned the transmission error remains parabolic with the maximum level still remaining very small (less than 0.34 arc second for the numerical examples). Tooth Contact Analysis (TCA) is used to simulate the conditions of meshing, determine the transmission error, and the bearing contact.
Litvin, F. L.; Handschuh, R. F.; Zhang, J.
The pattern of human tooth wear-the way it varies between teeth in the mouth-is crucial to our understanding of important questions in archeology and paleoanthropology, such as the contrasts in diet and behavior between Neanderthals and early modern humans in Europe and Asia, or with the adoption of agriculture in the Americas. Little is known, however, about the way in which wear patterns develop with increasing age or the way in which they differ between males and females. One explanation is that few living people show the high rates of tooth wear seen worldwide throughout the preindustrial archaeological record. The study described here investigates the macroscopic pattern of tooth wear in a unique group of known age and sex dental casts from living Canadian Inuit from Igloolik. The results show that the Igloolik people possessed a pattern of extremely heavy anterior tooth wear, relative to the first molar and the other posterior teeth, which is attributed to the use of the anterior teeth in cultural practices as well as the extreme and marginal environments in which they lived. Heavy anterior tooth wear was established at an early age and maintained throughout life; statistically significant differences were found between the wear patterns of males and females and are explained in terms of sexual division of labor within the community. This study highlights the need to understand both intra- and interpopulation variation in tooth wear patterns when interpreting patterns in past human groups. PMID:23125036
Clement, Anna F; Hillson, Simon W
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.
Corraini, Priscila; Baelum, Vibeke
Teeth represent an essential component of the foraging apparatus for any mammal, and tooth wear can have significant implications for survival and reproduction. This study focuses on tooth wear in wild baboons in Amboseli, southern Kenya. We obtained mandibular and maxillary tooth impressions from 95 baboons and analyzed digital images of replicas made from these impressions. We measured tooth wear as the percent dentine exposure (PDE, the percent of the occlusal surface on which dentine was exposed), and we examined the relationship of PDE to age, behavior, and life history variables. We found that PDE increased significantly with age for both sexes in all three molar types. In females, we also tested the hypotheses that long-term patterns of feeding behavior, social dominance rank, and one measure of maternal investment (the cumulative number of months that a female had dependent infants during her lifetime) would predict tooth wear when we controlled for age. The hypothesis that feeding behavior predicted tooth wear was supported. The percent of feeding time spent consuming grass corms predicted PDE when controlling for age. However, PDE was not associated with social dominance rank or maternal investment. PMID:20721946
Galbany, Jordi; Altmann, Jeanne; Pérez-Pérez, Alejandro; Alberts, Susan C
Full Text Available Abstract Background Smoking is a risk factor of a number of oral diseases; the extent to which tobacco products influence dental aesthetics has not been widely investigated. The aim of this study was to determine satisfaction with own tooth colour of smokers and non-smokers and to investigate whether smokers have higher levels of self-assessed tooth discolouration compared to non-smokers Methods A cross sectional national study was conducted on sample of 6,000 UK adults. A total of 3,384 adults was interviewed. Smoking behaviour was recorded together with satisfaction with own tooth colour. Prevalence of perceived discolouration was measured by asking respondents to match their own tooth colour to one of a set of seven photographs of differing severities of discolouration. Results Twenty eight percent of smokers reported having moderate and severe levels of tooth discolouration compared to 15% in non-smokers. As well as more often perceiving discolouration smokers were also more likely to be dissatisfied with their own tooth colour compared to non-smokers. Conclusion The study provides further evidence of the negative impact of tobacco smoking on dental aesthetics in the general public. The evidence provided by the study may be of value in short interventions for smoking cessation in the dental setting.
Holt Ruth D
In dentistry, the term 'fusion' is used to describe a developmental disorder of dental hard tissues. In the permanent dentition, fusion of a normal tooth and a supernumerary tooth usually involves the incisors or canines. However, a few cases of fusion involving premolars have also been reported to date. We present a rare case in which fusion of the maxillary left second premolar and a supernumerary tooth in a 13-year-old girl was diagnosed using cone beam computed tomography (CBCT, Alphard-3030, Asahi Roentgen Ind. Co., Ltd.). The tooth was bicuspidized after routine nonsurgical root canal treatment, and the separated teeth underwent appropriate restoration procedures. The second premolar and supernumerary tooth remained asymptomatic without any signs of inflammation after a follow-up period of 9 years. Identification of anatomical anomalies is important for treatment in cases involving fusion with supernumerary tooth, and therefore the microscopic examinations and CBCT are essential for the diagnosis. Fused teeth can be effectively managed by the comprehensive treatment which includes both endodontic and periodontal procedures. PMID:25383352