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991.
Dye BA Vargas CM Lee JJ Magder L Tinanoff N 《Journal of the American Dental Association (1939)》2011,142(2):173-183
BackgroundThe authors conducted a study to describe the relationship between the oral health of young children and that of their mothers.MethodsUsing data from the Third National Health and Nutrition Examination Survey and a related birth certificate–linked file, the authors compiled a sample of 1,184 mother/child pairs for children aged 2 through 6 years. The authors performed logistic and cumulative logistic regression analyses by using children's caries experience and untreated caries status as dependent variables. They evaluated the mothers' untreated caries status and tooth loss status along with other covariates, including age, race/ethnicity and poverty status.ResultsChildren of mothers who had high levels of untreated caries were more than three times as likely (odds ratio [OR], 3.5; 95 percent confidence interval [CI], 2.0–6.2) to have higher levels of caries experience (treated or untreated dental caries) compared with children whose mothers had no untreated caries. A similar relationship was observed between mothers' tooth loss and caries experience among their children. The children of mothers with high levels of tooth loss were more than three times as likely (OR, 3.3; 95 percent CI, 1.8–6.4) to have higher levels of caries experience compared with children of mothers with no tooth loss; for mothers with moderate tooth loss, the OR was 2.3 (95 percent CI, 1.5–3.5).ConclusionsMothers' oral health status is a strong predictor of the oral health status of their children.Practice ImplicationsPreventive plans for children should be based on a caries risk assessment. The results of this study demonstrate that basic information obtained from the child's mother regarding her oral health status is valuable in helping the dentist determine the child's caries risk. 相似文献
992.
993.
Alveolar bone is the least stable of the periodontal tissues, because it is subjected to continuous modeling and remodeling. OBJECTIVE: To perform a histological and histomorphometric evaluation of bone modeling and remodeling of periodontal alveolar bone under experimental anaemia and polycythaemia. METHODS: Thirty Wistar rats were divided into three groups: control (C), animals were i.p. injected with 0.5 mL of saline solution; anaemia (A), animals were injected with 6 mg/100 b.w. of phenylhydrazine every 48 h; polycythaemia (P), animals were transfused with 2.5 mL/100 b.w. of 80% suspension of homologous erythrocytes. All the animals were sacrificed 14 days after the onset of the experiment. The mandibles were resected, fixed in formalin, radiographed, processed and embedded in paraffin. Bucco-lingually oriented sections were obtained at the level of the mesial root of the first lower molar, and stained with hematoxylin-eosin. Histological and histomorphometric studies were performed on the buccal and lingual plates of periodontal alveolar bone. RESULTS: Histological and histomorphometric studies showed a statistically significant decrease in bone formation both in buccal and lingual plates in group A (anaemia) as compared to group C (control). An increase in active bone formation was found in the lingual plate in group P (polycythaemia) as compared to group C (control). CONCLUSION: The results obtained using this experimental model evidenced alterations in bone modeling and remodeling under conditions of anaemia and polycythaemia and/or associated factors. 相似文献
994.
This clinical trial evaluated, over a 12-month period, the performance of brackets bonded to teeth etched and primed with Transbond Plus Self-Etching Primer (SEP) when compared with a conventional separate two-step etch and primer system. Thirty-nine randomly selected patients requiring fixed appliance therapy were entered into the study. Random allocation of each etching system, along with a 'split-mouth cross-quadrant' design was used. A total of 661 brackets were placed by two operators. The failure and survival rates of the brackets were determined for age and gender of the patients, each etching system, operator, mode of failure, tooth position in the dental arch, and number of manipulations prior to curing the adhesive. Statistical analysis showed that SEP had a significantly higher bond failure rate (11.2 per cent) than the conventional etch and primer system (3.9 per cent) at the P = 0.001 level. Cox's proportional hazards regression showed the conventional etch and primer system to have a 60 per cent reduced chance of bracket failure over a 12-month observation period, while males had a 2.4 times increased risk compared with females. The predominant mode of failure was at the composite enamel interface for the SEP, while for the conventional etch and primer system, it was within the composite adhesive. No statistically significant differences were found for the failure rate with respect to the age of the patient, operator, tooth location, or the number of manipulations of the bracket. This in vivo study showed that brackets bonded using SEP had an increased clinical bond failure rate compared with the conventional, separate, etch and prime system. 相似文献
995.
Fokkinga WA Kreulen CM Le Bell-Rönnlöf AM Lassila LV Vallittu PK Creugers NH 《American journal of dentistry》2006,19(6):326-332
PURPOSE: To study the fracture behavior of direct resin composite crowns with or without experimental fiber reinforcement. METHODS: Clinical crowns of single-rooted maxillary premolars were cut off at the cemento-enamel junction. Canals were prepared with Gates Glidden drills up to size 4. No additional post-space preparations were made. Roots were embedded in acrylic and canal entrances were standardized (depth 2 mm, diameter 1.75 mm). Three groups of 14 samples were treated as follows: (1) custom-made glass FRC post (EverStick Post); fibers 5 mm deep in the canal, (2) similar post-system as (1) with incorporation of a new type of glass fiber fabric, (3) no fiber reinforcement (control). Posts were cemented with resin cement (Panavia F). Resin composite crowns (Filtek Z250) were made using an anatomically formed mold. Static load until fracture was applied using a universal loading device with a cylindrical bar (diameter 2 mm) with a crosshead speed of 5 mm/minute (loading angle: 30 degrees to the tooth long-axis). Failure modes were categorized as favorable and unfavorable failures. RESULTS: There was no significant difference in mean failure loads among the four groups (P > 0.05). Favorable failures occurred significantly more often in Group 2 than in the other groups (P < 0.05). The results suggest that an incorporated glass fiber fabric does not affect the load-bearing capacity of resin composite complete crowns on structurally compromised and non-vital premolars. Incorporation of a glass fiber fabric, however, has a beneficial effect on the failure mode. 相似文献
996.
OBJECTIVES: The light absorption of dental photoinitiators should correlate with the spectral emission profiles of dental light curing units compared on an equivalent basis. Spectral data of dental photoinitiators and light curing units can be used to define the photon absorption efficiency (PAE) obtained by integrating the product of the absorption and emission spectra in terms of photons. This parameter can be used to identify the best performance for photochemical process with specific photoinitiators. METHODS: The efficiency of two LED and one QTH lamps were tested comparing their performances with the photoinitiators camphorquinone (CQ); phenylpropanedione (PPD); monoacylphosphine oxide (Lucirin TPO); and bisacylphosphine oxide (Irgacure 819). Absorption and emission spectra of the photoinitiators and the LED (Ultrablue I and Ultrablue IS) and QTH (Optilux 401) LCUs were determined in the 360-550nm range. RESULTS: CQ exhibited an absorption centered in the blue region and, although the maxima of PPD, MAPO, and BAPO were in the UV-A region, their absorption extended to the visible region. Power output maxima of the LCUs were at 467 (Ultrablue I), 454 (Ultrablue IS) and 493nm (Optilux 401), and the total power densities were 170+/-1, 470+/-4 and 444+/-4mW/cm(2), respectively. SIGNIFICANCE: The use of the PAE allows a prediction of the most efficient photoinitiator/LCU systems. For similar photoinitiator concentrations, Lucirin and CQ are most efficiently photoinitiated by the QTH unit, whereas the high-power LED device is more efficient for Irgacure. PPD is photoactivated similarly by both LCUs. 相似文献
997.
OBJECTIVE: This research compared the clinical response of two different peroxide-containing gel formulations delivered using self-applied whitening strips. METHODOLOGY: A randomized, double-blind clinical trial was conducted to compare a one-week 10% hydrogen peroxide thin (0.13 mm) bleaching gel (Crest Whitestrips Premium) to a marketed two-week 6% hydrogen peroxide strip (0.20 mm) control (Crest Whitestrips). The maxillary arch was treated twice daily for 30 minutes. Efficacy (L*a*b* color change) was measured objectively by digital image analysis after one and two weeks. RESULTS: A total of 40 adults ranging from 19-48 years of age participated in the study. Both treatments were effective in whitening teeth, as evidenced by a statistically significant improvement from baseline (p < 0.001) beginning at one week. At that time, the adjusted mean deltab* (SE) (yellowness reduction) for the 10% strip was -2.42 (0.147) compared to -1.91 (0.143) for the 6% strip, with the treatments differing significantly (p = 0.02). At two weeks, the adjusted mean deltab* (SE) for the 10% strip was -3.31 (0.182) compared to -2.49 (0.167) for the control. After two weeks, treatments differed significantly (p < 0.02) for deltab* and deltaL* (lightness improvement). Comparing results from two weeks of the 6% control strip to one week of the 10% strip, the mean deltab* treatment difference was -0.07 (90% confidence interval from -0.44 to +0.31). Both treatments were generally well tolerated, with mild and transient tooth sensitivity or oral irritation representing the most common adverse events. CONCLUSION: Vital bleaching with 10% hydrogen peroxide strips at one week was as effective as 6% hydrogen peroxide strips used for two weeks. 相似文献
998.
Effect of different application and polymerization techniques on the microleakage of proximal resin composite restorations in vitro 总被引:2,自引:0,他引:2
This in vitro study investigated cervical microleakage of proximal resin composite restorations placed with three application and polymerization techniques. Uniform mesio-occlusal-distal (MOD) preparations featuring cervical margins above (mesial) and below (distal) the CEJ suitable for restoration with resin composite were copy milled into 33 recently extracted permanent molars. The teeth were divided randomly into three groups of 11 teeth and restored using a conventional incremental technique (Group A) and two novel curing devices (Groups B and C). After 24 hours, a dye penetration test was used to assess microleakage. Conventional placement in preparations with cervical margins in enamel had significantly lower interfacial leakage scores than those recorded for placement in preparations with margins in cementum regardless of the technique used to place the restorative material. Use of the two novel curing devices conferred no advantage in reducing microleakage irrespective of where preparation margins were placed. 相似文献
999.
The aim of this study is to document reasons for tooth loss in disadvantaged Jordanians who seek free dental care at the University Hospital/Dental Clinics. A 4-year (1998-2001) prospective study was undertaken involving 2200 randomly selected patients from this subpopulation. Of their 3069 lost teeth, 46.9% were lost due to caries and its sequel; 18% were lost because of periodontal disease; 8% were lost for a combination of caries and periodontal disease; 19.4% for pre-prosthetic reasons; 4% for orthodontic reasons; 2.8% for eruption problems and 0.7% due to trauma. Logistic regression analysis for reasons of tooth loss in this sector revealed that caries and its sequel was the predominant cause of tooth loss in patients 相似文献
1000.
V V Afanas'ev T G Robustova I F Romacheva M O Ter-Markar'ian N S Makeeva 《Stomatologii?a》1989,68(2):35-36
A novel technique is offered for treatment of sialadenitis. Ultraviolet irradiation conductors are inserted into the gland via its major duct for subsequent intracorporeal UV therapy of the gland. The results of the treatment are analyzed in 57 cases of sialadenitis observed during 1 to 2.5 years. The technique proved effective enough to be recommended for practical application. 相似文献