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41.
42.
U.Glendor A.Halling L.Bodin L.Andersson Å.Nygren G.Karlsson B.Koucheki 《Dental traumatology》2000,16(1):16-23
Abstract – The aim was to account for the total time spent by professional care‐givers (direct time) and by patients and companions engaged as support and help (indirect time) to treat and otherwise attend to children and adolescents with dental trauma to primary and permanent teeth. The study was based on a random sample of 192 children and adolescents with dental traumas reported to an insurance company and prospectively followed up by telephone interviews over a period of 2 years after the trauma episode. On average, direct time represented 16% of total time for all visits for dental trauma to permanent teeth and 11% for trauma to primary teeth. The most extensive type of indirect time was transport time, which took up 30% of the total time spent on injuries to permanent teeth and 36% for injuries to primary teeth. Multiple regression analysis of the impact of dental and demographic injury variables on the time variables showed that complicated trauma was associated with extended time, direct as well as indirect, for permanent and primary teeth injuries. Our estimate of the average relative increase in total time spent by patients and companions in cases of complicated injury to permanent teeth was 117% (95% confidence interval [CI], 52–211) for patients and 112% (95% CI, 42–217) for companions. For transport time a strong predictor was access to a dental clinic near the place of residence. Lack of access could extend the average transport time by 180% (95% CI, 80–335) for patients and 163% (95% CI, 67–317) for their companions in cases of injuries to primary teeth. 相似文献
43.
Our aim was to investigate the effect of TiF4 solutions on mineral loss on enamel and dentine in vitro. Samples were fluoridated 1 x 5 min per day with 1.64% w/v TiF4 or 2.2% w/v NaF solutions, each with a pH of 1.2, and then subjected to a cyclic de- and remineralization procedure for 5 days. Demineralization was performed for 6 x 10 min per day with citric acid (pH 2.3). In controls no fluoridation was performed. Mineral content was determined by longitudinal microradiography. Enamel mineral loss was markedly reduced by both fluoride solutions, but TiF4 was significantly more effective than NaF: cumulative mineral loss on day 3 was 61.7 +/- 15.0 microm in the NaF and 34.2 +/- 13.1 microm in the TiF4 group (p < or = 0.001) compared with 121.0 +/- 27.0 microm in the control group. Dentine mineral loss ceased after both TiF4 and NaF applications (cumulative mineral loss on day 5 in controls: 61.0 +/- 17.0 microm, in the TiF4 group: 15.4 +/- 13.4 microm and in the NaF group: 21.8 +/- 11.8 microm). Both TiF4 and NaF application reduced mineral loss both on enamel and dentine, which could open new possibilities for a symptomatic therapy of erosions. 相似文献
44.
The aim of this study was to evaluate the diagnostic accuracy of a well-defined clinical examination for diagnosing anterior disc displacement with and without reduction. A series of 40 patients with temporomandibular disorder (TMD) history were examined according to well-defined routine criteria. This examination included detailed history-taking, standardized clinical head and neck examination that included measurements of the range of motion, palpation of the temporomandibular joints and muscles of mastication for pain and auscultation of joint sounds. Magnetic resonance images of the joints were used as 'gold standard'. Diagnostic accuracy of the clinical examination was 83% for determining normal disc-condyle relationship, 72% for diagnosing anterior disc displacement with reduction, and 81% for diagnosing anterior disc displacement without reduction. Our results suggest that anterior displacement of the disc can be diagnosed with considerable accuracy using a well-defined clinical examination only. Therefore, we conclude that not all patients with TMD symptoms require magnetic resonance imaging examination before treatment. 相似文献
45.
46.
Dimensional reproduction in rotational panoramic radiography 总被引:1,自引:0,他引:1
W D McDavid G Tronje U Welander C R Morris 《Oral surgery, oral medicine, and oral pathology》1986,62(1):96-101
The customary mathematical expressions for magnification in rotational panoramic radiography are examined. It is shown that although these expressions yield correct results for small objects placed perpendicularly to the central ray of the beam, they must be corrected in other situations. 相似文献
47.
48.
Wear behavior of new composite restoratives 总被引:3,自引:0,他引:3
This study investigated the wear resistance of recently introduced nanofill (Filtek Supreme [FS], 3M-ESPE) and ormocer (Admira [AM], Voco) composites and compared their wear characteristics to microfill (Filtek A110 [AO], 3M-ESPE]), minifill (Esthet X [EX], Dentsply; Filtek Z250 [ZT], 3M-ESPE) and polyacid-modified (Dyract AP [DY], Dentsply) composites. Six specimens were made for each material. The specimens were conditioned for one week in distilled water at 37 degrees C and subjected to wear testing at 20 MPa contact stress against SS304 counter-bodies using reciprocal compression-sliding wear instrumentation. Distilled water was used as lubricant. Wear depth (microm) was measured using profilometry every 5,000 cycles up to 20,000 cycles. The results were analyzed using ANOVA/Scheffe's test (p<0.05). Wear of the materials was cycle and fatigue dependent. Although no significance in wear was observed between materials after 5,000 cycles of wear testing, significant differences were observed at 10,000 cycles and greater. After 20,000 cycles of wear testing, ranking was as follows: ZT > DY >AM > AO > FS > EX. Wear ranged from 39.90 microm for EX to 113.32 microm for ZT. The wear resistance of ZT and DY was significantly lower than AO, FS and EX In addition, ZT experienced significantly more wear than AM. Under the conditions of this in-vitro study, the wear resistance of nanofill and ormocer composites was comparable or superior to polyacid-modified, microfill and minifill composites. 相似文献
49.
Punch biopsies were obtained from the buccal gingiva of the lower third molars. Thin nerve fibres, immunoreactive for calcitonin gene-related peptide (CGRP) or substance P (SP), with possible sensory function, were found in the propria often close to the epithelium, sometimes even penetrating into the basal layers. gamma-Melanocyte stimulating hormone (gamma-MSH)-like immunoreactivity was found in sparsely distributed single cells (except in one specimen containing a dense infiltration), resembling neutrophilic granulocytes of the propria. gamma-MSH was present in several single smooth axons and in thick axon bundles of the propria. Surrounding the blood vessels, neuropeptide Y (NPY), tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine amide (PHI) immunoreactive nerve fibres were observed. NPY and TH-positive fibres probably represent sympathetic nerve terminals and VIP/PHI-immunoreactive ones may have a parasympathetic function. Papillae of the propria contained VIP-positive fibres not obviously related to blood vessels. The distribution in papillae of PHI-like immunoreactivity was similar but the PHI-positive reaction was also present in a few cells of the propria, especially near blood vessels. Somatostatin (SOM)-positive reaction occurred in a few dendritic-type cells near or in the epithelium and single nerve fibres close to the epithelium. Several thick axon bundles of the propria contained neurofilament (NF)-immunoreactive material. Some thin NF-fibres were found in the papillae and some seemed to penetrate into the epithelium. No galanin, methionine-enkephalin, parathyroid hormone or proctolin immunoreactive material was found. The rather rich content of several neuropeptides in human attached gingiva, as well as other neurochemical markers, is probably associated with sensory and autonomic functions. 相似文献
50.
This study investigated the use of various light-curing regimens with standardized light energy density on the effectiveness of cure of a visible light activated resin composite (Z100, 3M-ESPE). A light-cure unit (Variable Intensity Polymerizer (VIP), BISCO Inc) which permitted individual control over time and intensity, was used. The five light-curing modes investigated include Pulse Delay (PD), Pulse Cure (PC), Soft-start (SS), Turbo (T) and Control (C). Effectiveness of cure was established by measuring the top and bottom Knoop hardness of 2-mm thick composite specimens using a digital microhardness tester (n=5, load=500g; dwell time=15 seconds) immediately and at one-day post-polymerization. Data obtained was analyzed using one-way ANOVA/Scheffe's post hoc test and Independent Samples t-tests (p<0.05). Top KHN observed immediately after polymerization with C was significantly lower than PD. At one day post-polymerization, the top KHN obtained with C was significantly lower than PD, SS and T. No significant difference in bottom KHN was observed among the different curing modes immediately after curing. At one day post-polymerization, the bottom KHN obtained with C was significantly lower than SS and T. Regardless of curing regimens, top and bottom values at one day were significantly higher than those observed immediately after light polymerization. No significant difference in mean hardness ratio was observed among the different curing regimens immediately and one day later. Effectiveness of the cure at the bottom surfaces of composites may be increased by soft-start and turbo polymerization regimens. 相似文献