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Lack of cooperation in pediatric dentistry--the role of child personality characteristics.

PURPOSE: This study aimed to investigate fear, temperament, behavioral symptoms and verbal intelligence in a study group of uncooperative child dental patients, partly in comparison with a reference group of ordinary child dental patients. A second aim was to explore a hypothesis of heterogeneity by searching for subgroups within the study group. METHODS: Parents of 86 study group children (36 aged 4-to 7- years and 50 aged 8- to 12-years) and 117 reference group children (8- to 12-years) answered a questionnaire concerning dental and general fear, temperament and general behavior. Study group children performed a vocabulary test to measure verbal intelligence. Data were analyzed with a variable-based and a person-based approach. RESULTS: In addition to dental fear, a higher level of impulsivity most clearly discriminated study group from reference group children. Cluster analyses revealed four different fear and personality subgroups within the study group. CONCLUSIONS: Uncooperative child dental patients constitute a heterogeneous group. Subgroups with different fear, temperament and behavior problem profiles can be identified. These subgroups could be presumed to benefit from different treatment regimens, which should be further investigated.

Analysis of Variance↗

A laboratory comparison of the efficacy of battery-operated, non-rechargeable power toothbrushes.

PURPOSE: To evaluate the cleaning efficacy of three battery-operated, non-rechargeable, oscillating/rotating power toothbrushes, using a robot system to simulate normal clinical toothbrush use. MATERIALS AND METHODS: The study compared the cleaning efficacy of the new Braun Oral-B D4/EB4 with the Actibrush and the Dr. Best Powerclean in two independent experiments. Plaque substitute was applied to the artificial teeth of typodonts, which were cleaned by the robot system for a total of 2 minutes at a brushing force of 1.95 N. The remaining plaque substitute on buccal + lingual/palatal and occlusal surfaces, as well as gingival margin and interproximal sites, was measured using a computerized vision system. RESULTS: The new D4/EB4 was found to remove more plaque substitute than the Actibrush at all sites, and for all surfaces, lingual surfaces and occlusal surfaces the difference in favor of the D4/EB4 was statistically significant (P < 0.05). In comparison with the Powerclean toothbrush, the D4/EB4 was significantly more effective at all sites (P < 0.001). These results indicate that not all battery-operated oscillating/rotating power toothbrushes have equal efficacy with respect to plaque removal and that, in this series of laboratory experiments, the Braun Oral-B D4/EB4 was more effective than the Actibrush and the Dr. Best Powerclean.

Dental Plaque↗

Effect of four intermediate layer treatments on microleakage of Class II composite restorations.

This in vitro study examines the marginal sealing ability of four different intermediate materials applied before placement of a condensable composite. Class II preparations were made with gingival margins placed 1.0 mm apical to the cementoenamel junction of 60 extracted teeth, randomly assigned to five groups of 12. Following restoration, teeth were thermocycled, soaked in 0.5% basic fuchsin, and sectioned longitudinally. The resin-modified glass ionomer cement demonstrated significantly less microleakage than the use of a dentin bonding agent alone or in combination with flowable composite, flowable compomer, or autoploymerizing composite (p < 0.05, Dunn's test). This study supports the use of the glass ionomer open sandwich technique in deep Class II direct composite restorations.

Compomers↗

Clinical evaluation of a polyacid-modified resin composite (Dyract) in class III cavities: three-year results.

This study evaluated the three-year clinical performance of a polyacid-modified resin composite material, Dyract (DeTrey/Dentsply, Konstanz, Germany), in Class III cavities. Sixty-two Class III cavities in 30 patients were restored with Dyract. Restorations were clinically evaluated at baseline, one-, two- and three-year recalls according to the modified Ryge criteria by two experienced, calibrated examiners. After three years, the retention rate was 96.7%. At the one-year interval, one restoration had to be replaced due to sensitivity. At the two-year recall, one restoration, with a caries lesion adjacent to its margin, was clinically unacceptable and had to be replaced. Except for these two restorations, all other restorations were clinically acceptable in regard to color match, marginal discoloration, wear or loss of anatomical form, caries, marginal adaptation and surface texture after three years. At the end of three years, marginal discoloration was statistically significant (p=0.017) but did not require replacement of any of the restorations. Dyract exhibited significant marginal discoloration after three-year clinical performance in Class III cavities.

Adolescent↗

Relating visual and radiographic ranked scoring systems for occlusal caries detection to histological and microbiological evidence.

This study compared a visual ranked scoring system and a radiographic ranked scoring system for occlusal caries detection with the level of infection of dentin. Seventy-five third-molars, designated for extraction, were professionally cleaned. Caries was scored according to a visual ranked scoring system at a selected site in the groove-fossa system. Radiographs of the teeth were available and caries was recorded along a five-point ranked scoring system. Each tooth was extracted and hemi-sectioned through the investigation site under aseptic conditions. A burful of dentin was removed from the EDJ of one of the section faces and these samples were processed to establish the level of dentin infection. The depth of the lesion was assessed on the other section face using a five-point ranked histological scoring system. A strong relationship was observed between the histological lesion depth and visual score (r(s)=0.93) while a moderate relationship was seen between lesion depth and radiographic scores (r(s)=0.77). The dentin from teeth with cavities exposing dentin was heavily infected. The dentin from teeth with microcavities or grey discoloration of the dentin was less infected than the lesions with frank cavitation (score 4) (p<0.05, t-test), but more infected than the initial lesions (p<0.05, t-test). The latter lesions showed minimal infection. A similar tendency was seen with respect to increasing radiographic scores and the level of infection of the dentin.

Colony Count, Microbial↗

Pulpal response to a fluoride-releasing all-in-one resin bonding system.

Pulp tissue reactions to a fluoride-releasing all-in-one resin bonding system (Reactmer Bond and Reactmer Paste) in non-exposed monkey teeth were histopathologically evaluated at three, 30, and 90 days after restoration. No serious inflammatory reactions of the pulp, such as necrosis or abscess formation, were observed. At 90 days in the Reactmer group, odontoblastic change and inflammatory cell infiltration were not observed, and slight irritation dentin formation was formed. The pulpal response of the Reactmer group was minimally different from that of the control group. Consequently, the Reactmer system was determined as being biologically compatible with vital pulps.

Abscess↗

Effects of a refrigerated amalgam bonding system on fracture resistance.

This in vitro study evaluated the effectiveness of using an amalgam bonding system at refrigerated temperature to regain fracture resistance in molars with large mesial-occlusal-distal restorations. Nineteen pairs of homologous contralateral pairs of third molars were used, with control teeth remaining intact. Although the bonded amalgam group developed 81% of the fracture strength values of the intact teeth, the intact teeth were found to have significantly higher fracture strength values (p = 0.0326, paired t-test).

Dental Amalgam↗

Dimensional change in dentures processed in silicone and stone moulds.

Anecdotal evidence suggests that many dental laboratories are surrounding the teeth and gingival margins of the wax patterns for complete dentures with silicone laboratory putty prior to investing in dental stone or plaster to facilitate deflasking and polishing. This project investigates differences in dimension during processing when putty is used. Two groups of ten standardised dentures, one group with silicone, one group without were processed. Cross arch measurements were made before and after processing using an eight hour curing cycle followed by slow cooling. No statistically significant difference in change in dimension was observed between the two groups, indicating that this is an acceptable method.

Calcium Sulfate↗

The effect of radiation on the permeability of human saphenous vein to 17 beta-oestradiol.

Radiation therapy is an effective way of treating many forms of cancer, however, there are some indications that it may facilitate the development of metastasis. The question arises whether radiation therapy during cancer treatment might result in an alteration of the permeability of the tissues being treated. This alteration in the permeability might lead to metastatic cells escaping from the irradiated tissue, leading to the spread of cancer to other sites in the body. Because of the above implication, we determined the diffusion kinetics of a radioactive marker, 17 beta-oestradiol, through human saphenous vein before and after a single half hour exposure to 60 Gy of 60Co gamma-irradiation. Six clinically healthy saphenous vein specimens (mean patient age +/- standard deviation 57 +/- 13 years; age range 41-77 years) were obtained during cardiac surgery. In vitro flux rates of 17 beta-oestradiol were determined through use of a flow-through diffusion apparatus immediately after irradiation for a period of 24 hours. No statistically significant differences could be demonstrated for the flux rates of 17 beta-oestradiol through the non-irradiated and 60 Gy irradiated saphenous vein tissue. These findings strongly suggest that irradiation at 2 Gy/min and a total dose of 60 Gy would not alter the permeability of the venous wall. We have demonstrated that the in vitro flow-through diffusion method is capable of measuring permeability aspects of endothelial cell layers in saphenous vein biopsies under conditions resembling clinical reality.

Adult↗

Effect of different artificial aging conditions on ceramic-composite bond strength.

PURPOSE: The purpose of this study was to evaluate the influence of different storage conditions on the bond strength of adhesive bonding systems to yttria-partially stabilized zirconia ceramic. MATERIALS AND METHODS: Acrylic glass tubes filled with composite resin were bonded to ceramic disks. After sandblasting and ultrasonic cleansing of the ceramic samples, they were bonded using five bonding methods. Samples were tested for tensile bond strength following five different storage conditions: 3 days in distilled water at 37 degrees C, 31 days in distilled water at 37 degrees C, 37,500 thermocycles between 5 and 55 degrees C within 31 days, 150 days in distilled water at 37 degrees C, and 150 days in distilled water with 37,500 thermocycles performed at intervals. RESULTS: Mean resin bond strength values ranged from 7.7 to 41.9 MPa. There were statistically significant differences among groups, as revealed by the Kruskal-Wallis test. Some storage conditions influenced the resin bond strength statistically significantly, as revealed by the Wilcoxon rank sum test modified by Bonferroni-Holm. CONCLUSION: Thermocycling had a much higher impact on the durability of the resin bond strength to zirconia ceramic than did water storage at a constant temperature.

Adhesiveness↗

Alumina ceramic implant abutments used for single-tooth replacement: a prospective 1- to 3-year multicenter study.

PURPOSE: The aim of the study was to compare results after 1 and 3 years when single crowns supported by CerAdapt (test) ceramic abutments or CeraOne (control) titanium abutments were loaded. MATERIALS AND METHODS: The material was divided into two groups: in group A, 69 (34 test, 35 control) abutments/crowns from all involved clinics were followed for 1 year; and in group B, 20 (10 test, 10 control) abutments/crowns from one of the clinics were followed for 3 years. RESULTS: No implant failed, giving a cumulative success rate of 100% for the implants. Two CerAdapt abutments in group A fractured, giving a cumulative success rate of 93% for the CerAdapt and 100% for the CeraOne abutments after 1 year. No abutment failed in group B, giving a cumulative success rate of 100% both for the CerAdapt and the CeraOne abutments between 1 and 3 years. The CerAdapt fractures might have been due to the fact that the abutments were impaired through too-extensive preparation and/or had been exposed to a too-high bending moment. Almost no marginal bone loss was recorded, indicating a stable bone situation both at CerAdapt and CeraOne abutments on single-tooth implants. Healthy conditions, with a relatively stable level of the periimplant mucosa in relation to the abutment/crown, were recorded for soft tissues both at CerAdapt and CeraOne abutments. Both clinicians and patients rated the esthetic result as excellent for practically all cases. CONCLUSION: The results demonstrate the esthetic possibilities and the safety of single-tooth replacement when accepted treatment concepts are followed and documented components are used. The tested abutments worked well, although the fractured CerAdapt abutments indicate that ceramic abutments are more sensitive to handling procedures than the titanium abutments.

Adolescent↗

Influence of occlusal factors on treatment outcome: a study of 109 consecutive patients with mandibular implant-supported fixed prostheses opposing maxillary complete dentures.

PURPOSE: This study was undertaken to investigate the relationship between occlusal variables and clinical and radiologic findings as well as patient response to treatment outcome in patients with mandibular implant-supported fixed prostheses opposing maxillary complete dentures. MATERIALS AND METHODS: The study group consisted of 109 consecutive patients attending for annual control. They had received their mandibular implant-supported prostheses according to the Brånemark system on average 8 years previously (range 1 to 27 years). All patients were interviewed with standardized questions by one examiner, who also performed the clinical examination. The questions focused on the patients' opinion on masticatory and prosthetic function and problems. The clinical examination comprised occlusal and prosthetic factors and the health of the oral mucosa. RESULTS: The great majority of the patients were very satisfied with their present dental situation and masticatory function. Two thirds reported no problems with their maxillary complete dentures at all. Balanced occlusion was found bilaterally in 61%, and a further 4% had balanced function on one side. More than one third thus lacked balanced occlusion. Only about 60% had optimal occlusion, and 8% had poor occlusion according to common prosthodontic criteria. This was interpreted as a continuing impairment of the occlusion with time. The mean bone loss was 0.5 mm, according to available radiographs, for a mean observation period of 54 months. There were no or only weak correlations between the variables examined. CONCLUSION: The occlusal factors registered were of limited importance for patient satisfaction and treatment outcome recorded clinically and radiographically at follow-up examination of the actual prosthodontic rehabilitation.

Aged↗

Enamel fluoride retention after application of fluoride-containing rubber cups.

PURPOSE: To compare the fluoride retention in bovine enamel after using fluoride-containing rubber cups or a conventional rubber cup in combination with a fluoride-containing polishing paste. MATERIALS AND METHODS: From each of 20 bovine incisors, 5 enamel slabs with a diameter of 3 mm were sectioned and assigned to 5 groups (A,B,C,D,E). Group A was left untreated and served as the negative control. Group B was polished with a rubber cup combined with a fluoride-containing prophylaxis paste for 10 s (Hawe Cleanic). Groups C and D were treated in the same manner by using a fluoride-containing rubber cup with 2,262 ppm or 9,048 ppm fluoride as NaF. Group E enamel was brushed for 10 s with a toothbrush and a slurry of distilled water and fluoride gel with 12,500 ppm fluoride as NaF and AmF (Elmex Gelee) and served as the positive control. Th e specimens were analyzed using the method of Caslavska et al. After determining the KOH soluble fluoride on the enamel surface, the content of structurally bound fluoride was analyzed in three consecutive layers of 30 microm. ANOVA with Bonferroni correction was used for statistical analysis (P< 0.05). RESULTS: For the KOH-soluble fluoride, Groups B and D accumulated more KOH-soluble fluoride than the negative control and less than the positive control. With respect to the structurally bound fluoride, the accumulation in Group D was higher when compared to all other groups. It was concluded that a rubber cup with 9,048 ppm fluoride may be an effective alternative to the use of a fluoride-containing prophylaxis paste.

Amines↗

One-year prosthetic outcomes with implant overdentures: a randomized clinical trial.

PURPOSE: This randomized clinical trial examined implant overdenture (IOD) fabrication and maintenance time and costs, adjustment and repair incidence, and patient satisfaction after 1 year. MATERIALS AND METHODS: Sixty-four patients received 2 mandibular implants and an IOD with either a bar with 2 clips or 2 ball attachments for denture retention. RESULTS: Fabrication time, number of appointments, and chair time for adjustments were similar for the 2 denture designs. The most common adjustments for both types were to the IOD contours. Ball-attachment dentures required about 8 times longer for repairs than bar-clip prostheses. Approximately 84% of patients with ball-attachment dentures needed at least 1 repair, versus 20% of those with a bar-clip mechanism. The most common repairs were replacement of the cap spring or cap for the ball-attachment IOD and replacement of a lost or loose clip for bar-clip dentures. DISCUSSION: Patients were equally and highly satisfied with the improvements in function, comfort, and appearance with both types of IOD compared to their original conventional dentures. CONCLUSIONS: Given equivalent levels of patient satisfaction with either method of retention and a much higher repair rate for the ball attachment, it is suggested that a bar-clip design be used rather than the particular ball attachment utilized in this study.

Adult↗

A comparison of dental caries and tooth loss for Iowa prisoners with other prison populations and dentate U.S. adults.

PURPOSE: When one compares National Health and Nutrition Examination Survey III (NHANES III) data to previous national surveys it appears that oral health in the United States has improved. The purpose of this study was to determine if this trend holds for prisoners in Iowa, specifically in regard to number of decayed teeth, number of decayed surfaces, and number of missing teeth. METHODS: This original research is a report of cross-sectional data regarding untreated decay and missing teeth. A representative sample of inmates newly admitted to the Iowa Medical Classification Center (IMCC) between June and December 1998 was selected. Oral health data were collected from records obtained as the result of dental treatment screening examinations conducted by the IMCC staff dental hygienist. Demographic data were obtained from questionnaires. The oral health status of this Iowa inmate population was compared with the status of previously studied samples of inmates throughout the nation using descriptive and parametric statistics and with dentate, noninstitutionalized U.S. adults using descriptive, non-parametric, and parametric statistics. RESULTS: Of the 174 study participants, 149 were male and 25 were female. On average, male inmates had 7.09 decayed teeth, 15.3 surfaces of decay, and 4.07 missing teeth. The female inmates averaged 5.56 teeth with untreated decay, 14.4 surfaces of decay, and 5.12 missing teeth. Findings showed that male Iowa inmates have more untreated decay than previously studied samples of inmates throughout the nation. IMCC Caucasian male inmates had 1.6 to 7.8 times as many untreated decayed teeth as previous inmates, while African American inmates showed 1.2 to 3.4 times as many untreated decayed teeth. The Iowa male inmates had fewer missing teeth than most of the inmate comparison groups. Compared with dentate, noninstitutionalized U.S. adults, the IMCC inmates, male and female combined, had 8.4 times the amount of untreated decay but similar numbers of missing teeth. CONCLUSIONS: Newly admitted male and female inmates were disparate from the general dentate U.S. adult population in terms of untreated decay. This also was found for IMCC male inmates compared to previous studies of male inmates. Inmates of both genders at IMCC did not appear to be disparate with the comparison population with regard to number of missing teeth.

Adolescent↗

The relation between xerostomia and hyposalivation in subjects with rheumatoid arthritis or fibromyalgia.

Aim of this study was to evaluate the relation between xerostomia and hyposalivation in 100 subjects with either rheumatoid arthritis or fibromyalgia, and further, to evaluate the predictive value of xerostomia on hyposalivation. Unstimulated and chewing stimulated whole saliva was collected in the morning with the subjects in a strict fasting condition and then about 2 hours later, after intake of a standardised breakfast. All participants filled in a questionnaire, mainly dealing with xerostomia. Forty subjects demonstrated a pathological fasting unstimulated whole saliva secretion rate, the corresponding number for fasting stimulated secretion being 39. For unstimulated, but not for stimulated saliva, the fasting secretion rate was significantly lower than the non-fasting. Xerostomia was reported by 74 subjects, this group having significantly lower both unstimulated and stimulated secretion rates than the non-xerostomic group. On the individual level, the predictive value of xerostomia on hyposalivation showed high sensitivity but unsatisfactory specificity. In conclusion, this study underlines the importance of applying strictly standardised procedures when collecting saliva, and that fasting unstimulated whole saliva is the diagnostic salivary secretion of choice. Finally, xerostomia was found to predict hyposalivation on a group, but not on an individual level.

Arthritis, Rheumatoid↗

Comparison of two tooth-saving preparation techniques for one-surface cavities.

The atraumatic restorative treatment technique (ART) is based on removing infected tooth material using only hand instruments and filling the subsequently cleaned cavity with adhesive material such as glass ionomer. As its name suggests, the ART technique should be atraumatic during treatment, as well as for the tooth itself as for the patient. It was primarily developed for treating people living in underserved areas of the world where resources and facilities such as electricity and trained manpower are limited. Many studies have evaluated the ART technique and the results have supported its application. However, a very limited number of studies have compared ART with more conventional techniques. For that reason, a study was conducted in Pakistan, to compare the ART technique with another more conventional treatment technique. The results of this study show that the preparations with hand instruments resulted in smaller sized cavities and therefore may be less traumatic to the tooth. It was also associated with less pain reactions compared to the more conventional technique. Although preparations with hand instruments required more time, this did not seem to affect the survival of restorations. The survival of glass ionomer cement restorations made with hand instruments was comparable with single surface amalgam restorations made with a more conventional technique. Recurrent caries was not associated with any glass ionomer cement restorations made with hand instruments. The retention rate of glass ionomer sealants was low, however one dentist had a sealant retention rate of 81.5 percent that suggests that this procedure can be performed satisfactorily in conjunction with a glass ionomer cement restoration. Operator variances did seem to affect the restorations. Survival of glass ionomer restorations made with both hand and rotary instruments varied for different operators. Similarly, the retention of fissure sealant also varied amongst operators. Operator differences also influenced the extent of tooth substance lost due to cavity preparation. The ART technique is a feasible approach towards the treatment of dental caries especially of one-surface lesions for underserved populations.

Adolescent↗