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This paper, which is presented in two parts, reviews the work on dental materials published in 1974. Included in Part I were sections on amalgam, casting alloys, denture base polymers, composite filling materials, soft lining materials, fissure sealants, impression materials, dental ceramics and model and die materials. A review of the literature relating to cements, dental implants and dental biomechanics is presented in Part II.  相似文献   
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BACKGROUND: The aim of this randomized clinical trial was to evaluate the treatment of gingival recession associated with non-carious cervical lesions by a coronally advanced flap alone (CAF) or in combination with a resin-modified glass ionomer restoration (CAF+R). METHODS: Nineteen subjects with bilateral Miller Class I buccal gingival recessions associated with non-carious cervical lesions were selected. The recessions were assigned randomly to receive CAF or CAF+R. Bleeding on probing (BOP), probing depth (PD), relative gingival recession (RGR), clinical attachment level (CAL), non-carious cervical lesion height (CLH), and dentin sensitivity (DS) were measured at baseline; 45 days; and 2, 3, and 6 months postoperatively. Keratinized tissue width (KTW) and keratinized tissue thickness (KTT) were measured at baseline and 6 months. The height of the non-carious cervical lesion located on the root and crown were estimated, allowing calculation of root coverage. RESULTS: Both groups showed statistically significant gains in CAL and soft tissue coverage. The differences between groups were not statistically significant for BOP, PD, RGR, CAL, KTW, and KTT after 6 months. The percentages of CLH covered were 56.14% +/- 11.74% for CAF+R and 59.78% +/- 11.11% for CAF (P >0.05). The root and crown surfaces affected by the non-carious cervical lesion were 1.67 +/- 0.31 mm and 0.96 +/- 0.29 mm, respectively, for CAF+R and 1.59 +/- 0.37 mm and 1.01 +/- 0.33 mm, respectively, for CAF. The estimated root coverage was 88.02% +/- 19.45% for CAF+R and 97.48% +/- 15.36% for CAF (P >0.05). CAF+R reduced DS significantly compared to CAF (P <0.05). CONCLUSIONS: Both procedures provided similar soft tissue coverage after 6 months. Despite the fact that a greater reduction in DS was observed after CAF+R, longitudinal observations are necessary to confirm these results.  相似文献   
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Perception of discomfort by patients undergoing orthodontic treatment   总被引:10,自引:0,他引:10  
The purpose of this study was to determine the perception of discomfort over time by a group of 70 patients undergoing orthodontic treatment. Patients who were selected for comprehensive orthodontic treatment completed questionnaires before insertion of separators and initial arch wires and after placement at 4 hours, 24 hours, and 7 days. The level of discomfort during these time periods was assessed by a visual analogue scale. The results showed a significant increase in the level of discomfort after insertion of either separators or arch wires at 4 hours and 24 hours, but not at 7 days. No significant difference was found in the level of discomfort of patients more than 16 years of age compared with those 16 years and under. No significant difference in discomfort was found between the sexes. These results are useful in relating expectations of discomfort to patients who undergo orthodontic treatment.  相似文献   
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PURPOSE: Conscious sedation is a behavior modification adjunct taught in all postgraduate pediatric dental residency programs. It has been a decade since the last survey was done specifically related to didactic and clinical aspects of conscious sedation in postgraduate pediatric dental programs. The aim of the study was to determine the clinical and didactic experiences associated with conscious sedation in these programs and to compare some of the findings to those collected a decade ago. METHODS: A 31-item survey similar to that of a decade ago was constructed and sent to all pediatric dentistry program directors of accredited postgraduate and residency programs in the United States. The items covered several didactics including didactic topics, sedative agents, monitoring, and emergency policy among others. A follow-up mailing was done involving those who had not responded 6 weeks following the initial mailing. RESULTS: Fifty-four of 58 (93%) program directors returned the 31-item survey. The following are highlighted findings. Conscious sedation among residency programs was achieved most commonly with a combination of sedative agents used with N2O. Midazolam was more popular than chloral hydrate. The oral route was the predominant route of administration. More lecture hours were spent on conscious sedation than 10 years ago. The pre-cordial stethoscope, pulse oximeter, and blood pressure cuff were the most commonly used monitors. Sedative agent and anticipated depth of sedation were the factors most often considered in choosing monitors used during the sedation of a patient. The capnograph was being used more frequently than it was 10 years ago. Programs did not report an increase in sedation emergencies but practiced emergency drills more often and had increased numbers of individuals certified in Advanced Cardiac Life Support (ACLS) or Pediatric Advanced Life Support (PALS). The percent of the total patient population which required sedation is about 1-20%, with most directors reporting an increase in the numbers of sedations done in the past few years. CONCLUSIONS: While many factors remained unchanged or slightly modified when compared to the survey done a decade ago, the results of this study suggest that there has been significant changes in several key factors including the most frequently used sedative (i.e., midazolam) and increased preparation in the area of emergency preparedness.  相似文献   
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BACKGROUND: The aim of this study was to investigate the influence of current hormonal contraceptive medication on periodontal health in young females. METHODS: Fifty women aged 20 to 35 years (mean +/- SD: 29.7 +/- 4.7 years) had a comprehensive periodontal examination. Current and previous contraceptive pill use was assessed by a questionnaire. Periodontal assessment included plaque index, gingival index, probing depth, and attachment level at six sites per tooth. The periodontal health of current pill users was compared to that of women not taking the pill. RESULTS: Forty-two percent of subjects were taking the contraceptive pill at the time of periodontal examination. Current pill users had deeper mean probing depths compared to non-users (3.3 mm versus 2.7 mm; P = 0.006) and more severe attachment loss (2.6 mm versus 1.7 mm; P = 0.015). Pill users had more sites with bleeding on probing (44.0% versus 31.1%; P = 0.017). CONCLUSION: Current users of oral contraceptives had poorer periodontal health.  相似文献   
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Biofilms form on all hard non-shedding surfaces in a fluid system, i.e. both on teeth and oral implants. As a result of the bacterial challenge, the host responds by mounting a defence mechanism leading to inflammation of the soft tissues. In the dento-gingival unit, this results in the well-described lesion of gingivitis. In the implanto-mucosal unit, this inflammation is termed "mucositis". If plaque is allowed to accumulate for prolonged periods of time, experimental research has demonstrated that "mucositis" may develop into "periimplantitis" affecting the periimplant supporting bone circumferentially. Although the bony support may be lost coronally, the implant still remains osseointegrated and hence, clinically stable. This is the reason why mobility represents an insensitive, but specific diagnostic feature of "periimplantitis". More sensitive and more reliable parameters of developing and existing periimplant infections are "bleeding on probing", "probing depths" and radiographic interpretation of conventional or subtraction radiographs. Depending on the diagnosis made continuously during recall visits, a maintenance system termed Cumulative Interceptive Supportive Therapy (CIST) has been proposed.  相似文献   
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