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81.
Biazevic MG Michel-Crosato E Iagher F Pooter CE Correa SL Grasel CE 《Brazilian Oral Research》2004,18(1):85-91
The objective of this study was to investigate the impact of oral health conditions on the quality of life of elderly people in Joa?aba - SC, in Southern Brazil. A survey based on systematic sampling of clusters was carried out with 183 elderly people that belong to old age groups. The survey was conducted in order to assess the oral conditions of the participants (use of and need for prosthesis) based on the criteria from the World Health Organization publication "Oral Health Surveys, Basic Methods", 4th edition. The oral health impact profile (OHIP) was used to evaluate the impact of oral condition in the quality of life. ABIPEME (Brazilian Association of Market Research Institutes) criterion was used, together with the level of education and the number of people in the household to determine social inequalities. The participants were mostly women (82%) and the OHIP mean was 10.35. No correlation was observed between the OHIP level and formal education or between OHIP and number of residents per household. There was a correlation of 0.240 (p = 0.001) between ABIPEME and OHIP. The OHIP mean for those not using maxillary prosthesis was 12.48 and the mean for those using it was 9.81 (p = 0.399). The mean OHIP for those in need of maxillary prosthesis for those who did not need it was 13.00 and 8.88, respectively (p = 0.014). The same trend was found for the use and need for mandibular prosthesis. The conclusion was that the need for maxillary and mandibular prosthesis impacted the quality of life among the elderly population of Joa?aba. 相似文献
82.
The functional dentition of the domestic sheep lacks all upper incisors and the upper canines. Nevertheless, occurrence of a dental lamina and rudimental tooth primordia had been described in the upper incisor region of the sheep. The aim of this study was to describe temporo-spatial pattern of origin and regression of these rudimental tooth primordia by light microscopy, computer-aided three-dimensional reconstruction and morphometry of the dental epithelium. Transient existence of a dental lamina in the upper incisor region of the sheep and three epithelial thickenings on its deep mesenchymal margin has been observed at day of ontogeny (DO) 48-53. They could not been identified as full-value tooth primordia, because they did not induce differentiation of tooth mesenchyme, but they could represent last remnants of functional upper incisors in early ancestors of ruminants. Additionally, a large rudimental upper canine primordium near the sutura maxilloincisiva occurred at DO43, reached early cap stage at DO52 and started to regress at DO53. Thus, our findings showed a discrepancy between the embryonic and adult dental pattern in the sheep. Similar molecular mechanisms as described for diastemal tooth rudiments in rodents could be involved during regression of rudimental tooth primordia in the upper incisor region of the sheep. 相似文献
83.
Kreimann EL Miura M Itoiz ME Heber E Garavaglia RN Batistoni D Rebagliati RJ Roberti MJ Micca PL Coderre JA Schwint AE 《Archives of oral biology》2003,48(3):223-232
Boron Neutron Capture Therapy (BNCT) is a bimodal cancer treatment based on the selective accumulation of 10B in tumors and concurrent irradiation with thermalized neutrons. The short-range, high-LET radiation produced by the capture of neutrons by 10B could potentially control tumor while sparing normal tissue if the boron compound targets tumor selectively within the treatment volume. In previous studies, we proposed and validated the hamster cheek pouch model of oral cancer for BNCT studies, proved that absolute and relative uptake of the clinically employed boron compound boronophenylalanine (BPA) would be potentially therapeutic in this model and provided evidence of the efficacy of in vivo BPA-mediated BNCT to control hamster oral mucosa tumors with virtually no damage to normal tissue. We herein present the biodistribution and pharmacokinetics of a lipophilic, carborane-containing tetraphenylporphyrin (CuTCPH) in the hamster oral cancer model. CuTCPH is a novel, non-toxic compound that may be advantageous in terms of selective and absolute delivery of boron to tumor tissues. For potentially effective BNCT, tumor boron concentrations from a new agent should be greater than 30 ppm and tumor/blood and tumor/normal tissue boron concentration ratios should be greater than 5/1 without causing significant toxicity. We administered CuTCPH intraperitoneally (i.p.) as a single dose of 32 microg/g body weight (b.w.) (10 microg B/g b.w.) or as four doses of 32 microg/g b.w. over 2 days. Blood (Bl) and tissues were sampled at 3, 6, 12, 24, 48, and 72 h in the single-dose protocol and at 1-4 days after the last injection in the multidose protocol. The tissues sampled were tumor (T), precancerous tissue surrounding tumor, normal pouch (N), skin, tongue, cheek and palate mucosa, liver, spleen, parotid gland and brain. The maximum mean B ratios for the single-dose protocol were T/N: 9.2/1 (12h) and T/Bl: 18.1/1 (72 h). The B value peaked to 20.7+/-18.5 ppm in tumor at 24h. The multidose protocol maximum mean ratios were T/N: 11.9/1 (3 days) and T/Bl: 235/1 (4 days). Absolute boron concentration in tumor reached a maximum value of 116 ppm and a mean value of 71.5+/-48.3 ppm at 3 days. The fact that absolute and relative B values markedly exceeded the BNCT therapeutic threshold with no apparent toxicity may confer on this compound a therapeutic advantage. CuTCPH-mediated BNCT would be potentially useful for the treatment of oral cancer in an experimental model. 相似文献
84.
Serra e Silva FM Sawazaki R de Moraes M 《Journal of dentistry for children (Chicago, Ill.)》2007,74(3):228-230
The purpose of this case report was to describe the management of a mandibular dentigerous cyst in a 10-year-old male patient. Without any clinical symptom, the lesion was detected in a routine panoramic radiograph showing a well-defined osteolytic lesion that measured 3 cm in diameter, partially surrounding the crown of the canine, first molar, and second premolar displacing the teeth to the mandible's lower border. The apex of the teeth were still open. Under local anesthesia, the patient was treated by: extraction of the left deciduous canine and first and second deciduous molars; and marsupialization of the cystic cavity. After 30 months, the premolar had erupted and an orthodontic therapy was started to maintain space for the canine. 相似文献
85.
86.
87.
López-Arcas Calleja JM Cebrián Carretero JL González Martín J Burgueño M 《Medicina oral, patología oral y cirugía bucal》2007,12(5):E401-E403
The aneurysmatic osseus cyst is a very infrequent bone lesion which in some occasions can be found at the craniofacial skeleton. Among all the cystic lesions that can be found at the mandible or the maxilla it is very rare. On the other side it is at the same time very interesting in terms of its differential diagnose with other types of maxillary bone lesions We present the case of a Caucasian male with an aneurysmatic cyst located at the right angle of the mandible and a review of the literature concerning the case. We have focused on the differential diagnose, mainly with the malignancies that can be found at this location. We also comment the therapeutic options classically described for these kind of pathologies. In our patient, the surgical excision allowed a complete removal of the lesion and a posterior bone healing which made possible a implant-supported rehabilitation of the edentulous segment. 相似文献
88.
89.
Matheus Melo Pithon Márlio Vinícius de Oliveira Antonio Carlos de Oliveira Ruellas Ana Maria Bolognese Fábio Louren?o Romano 《Journal of applied oral science : revista FOB》2007,15(2):127-130
The purpose of the present study was to evaluate the shear bond strength to enamel and the adhesive remnant index (ARI) of both metallic and polycarbonate brackets bonded under different conditions. Ninety bovine permanent mandibular incisors were embedded in acrylic resin using PVC rings as molds and assigned to 6 groups (n=15). In Groups 1 (control) and 3, metallic and polycarbonate orthodontic brackets were, respectively, bonded to the enamel surfaces using Transbond XT composite according to the manufacturer''s recommendations. In Groups 2 and 4, both types of brackets were bonded to enamel with Transbond XT composite, but XT primer was replaced by the OrthoPrimer agent. In Groups 5 and 6, the polycarbonate bracket bases were sandblasted with 50-μm aluminum-oxide particle stream and bonded to the enamel surfaces prepared under the same conditions described in Groups 3 and 4, respectively. After bonding, the specimens were stored in distilled water at 37°C for 24 hours and then submitted to shear bond strength test at a crosshead speed of 0.5 mm/min. The results (MPa) showed no statistically significant difference between Groups 4 and 6 (p>0.05). Likewise, no statistically significant differences (p>0.05) were found among Groups 1, 2, and 5, although their results were significantly lower than those of Groups 4 and 6 (p<0.05). Group 3 had statistically significant lower bond strength than Groups 2, 4, and 6, but no statistically significant differences were found on comparison to Groups 1 and 5. A larger number of fractures at the bracket/composite interface were evidenced by the ARI scores. OrthoPrimer bonding agent yielded higher bond strength in the groups using either conventional or sandblasted polycarbonate brackets, which was not observed in the groups using metallic brackets. 相似文献
90.
Martinhon CC Italiani Fde M Padilha Pde M Bijella MF Delbem AC Buzalaf MA 《Archives of oral biology》2006,51(6):471-475
OBJECTIVES: This study investigated in situ the effect of iron (Fe) on the reduction of demineralization of bovine enamel, as well as on the composition of dental biofilm. DESIGN AND METHODS: Twelve volunteers were included in this blind crossover study, which was conducted in two stages of 14 days each. For each stage, the volunteers received palatal appliances containing four blocks of bovine enamel (4 mm x4 mm x 2.5 mm). Six volunteers dripped a solution of 15 mmol L(-1) ferrous sulphate onto the fragments and the remaining six dripped deionized water (eight times per day). After five minutes, a fresh 20% (w/v) sucrose solution was dripped onto all enamel blocks. During the experimental period the volunteers brushed their teeth with non-fluoridated dentifrice. After each stage, the percentage of surface microhardness change (%SMHC) and area of mineral loss (DeltaZ) were determined on enamel and the dental biofilm formed on the blocks was collected and analysed for F, P, Ca, Fe and alkali-soluble carbohydrates. The concentrations of F, Ca and Fe in enamel were also analysed after acid biopsies. RESULTS: There was a statistically significant increase in the P and Fe concentrations in the biofilms treated with ferrous sulphate (p<0.05), which was not observed for F, Ca and alkali-soluble carbohydrates. The group treated with ferrous sulphate had significantly lower %SMHC and DeltaZ when compared to control (p<0.05). CONCLUSIONS: These results showed that ferrous sulphate reduced the demineralization of enamel blocks and altered the ionic composition of the dental biofilm formed in situ. 相似文献