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At least 703 records · Page 39Linked to original sources
PubMed2000

Reconstruction of the orbit following trauma.

An overview of the approach to the surgical management of orbital trauma used within the Department of Oral and Maxillofacial Surgery at The University of Washington is presented. In particular this paper discusses our experiences with the use of transconjunctival incisions, a modified technique for the harvesting of cranial bone grafts, and the use of intra-operative C-T scanning. Also presented are the results of two studies performed on aspects of the management of orbital trauma within the Department.

Adult↗
PubMed2000

A comparison of the Braun Oral-B 3D plaque remover and the Sonicare plus electric toothbrush in removing naturally occurring extrinsic staining.

PURPOSE: To compare the extrinsic stain-removing properties and the safety of the Braun Oral-B 3D Plaque Remover and the Sonicare Plus electric toothbrush. MATERIALS AND METHODS: This randomized, parallel group, investigator-blinded study involved 67 subjects and was conducted over 6 weeks. After recruitment, the subjects received a baseline stain assessment (Lobene stain index) and a soft and hard tissue examination, and were then randomized to use either the Sonicare or the 3D device. All subjects were trained to use both devices, and instructed to brush twice daily with their assigned device for 2 min. The subjects' brushing technique was checked after 2 weeks. After a further 4 weeks, the subjects underwent a final stain assessment and soft and hard tissue examination. A questionnaire was also completed. RESULTS: At 6 weeks, oral hard and soft tissue examinations revealed no abrasion or damage in either group. Both brushes produced significant (P < 0.001) reductions from baseline in total stain score, stain area and intensity, but group comparisons showed that these reductions were significantly (P < 0.001) greater for the 3D device.

Adolescent↗
PubMed2000

Effect of light source position and bevel placement on facial margin adaptation of resin-based composite restorations.

PURPOSE: To evaluate the effect of direction of first cure and the presence or absence of a facial margin bevel on the adaptation of facial margins of Class III resin-based composite (RBC) restorations. MATERIALS AND METHODS: Custom polyvinyl siloxane (PVS) light shields were fabricated for both the mesial and distal surfaces of 20 extracted incisors. Class III cavities were prepared in the mesial and distal surfaces of the incisors. On the facial, lingual, and gingival margins of 20 of the preparations a 0.5 mm wide enamel bevel was placed. The lingual and gingival, but not the facial, margins were beveled on the other 20 preparations. The PVS light shield was adapted to the tooth and trimmed to allow 1-2 mm of the facial margin to be exposed on 10 of the beveled and 10 of the non-beveled preparations. For the remaining 20 preparations the PVS light shield was trimmed to allow access of the curing light only from the lingual. Teeth were restored with Prisma TPH RBC. Using the appropriate shield, restorations in the facial first cure group were cured first from the facial and then from the lingual. Restorations in the lingual first cure group were cured only from the lingual. Restorations were finished flush with enamel margins and thermocycled following storage. Samples were exposed to a 50% solution of silver nitrate followed by light exposure. Teeth were sectioned and microleakage was evaluated at three levels (incisal, middle, and cervical). Four evaluators (blinded to direction of cure) independently scored microleakage using a categorical evaluation scale. Statistical analysis included non-parametric descriptive statistics, Cohen's kappa, chi-square analysis, and Kruskal-Wallis ANOVA. RESULTS: Samples prepared without a facial bevel revealed significantly more (P = 0.01) microleakage than preparations with a facial bevel. At the most incisal level, restorations cured first from the facial revealed significantly more (P < 0.001) microleakage than restorations cured first from the lingual. At the middle and cervical levels, restorations cured first from the facial revealed significantly less (P < 0.001) microleakage than restorations cured first from the lingual. When a facial bevel was present, samples cured first from the facial showed significantly less (P < 0.001) microleakage than those cured only from the lingual.

Analysis of Variance↗
PubMed2000

Effect of gingival fluid on marginal adaptation of Class II resin-based composite restorations.

PURPOSE: To evaluate in vitro the marginal quality of Class II composite restorations at the gingival enamel margins as affected by contamination of the cavities with gingival fluid (GF) during different steps of resin bonding procedures. MATERIALS AND METHODS: 70 Class II cavities were prepared in extracted human molars and restored with composite using a multi-component bonding system (OptiBond FL/Herculite XRV; OPTI) or a single-bottle adhesive (Syntac Sprint/Tetric Ceram; SYN). The cavities were contaminated with human GF: C1 after acid etching, C2 after application of the primer (OPTI) or light-curing of the primer-adhesive (SYN), and C3 after light-curing of the resin adhesive (OPTI). Uncontaminated cavities were used as the control (C0). The restored teeth were subjected to thermocycling (TC) and replicated for SEM analysis of marginal gap formation. Microleakage at the gingival margins was determined by dye penetration with basic fuchsin. STATISTICS: non-parametric tests (Kruskal-Wallis test, Mann-Whitney test with Bonferroni correction). RESULTS: In both bonding systems, contamination with GF after acid etching (C1) did not impair the marginal quality; the mean percentages of continuous margin/mean depths of dye penetration were: OPTI: C0: 88.5%/0.10 mm, C1: 95.6%/0.04 mm; SYN: C0: 90.9%/0.08 mm, C1: 97.0%/0.05 mm. Marginal adaptation was adversely affected when GF contamination was performed after

Acid Etching, Dental↗
PubMed2000

Video rate confocal microscopic imaging of dentin/adhesive interfacial failure under load.

PURPOSE: To obtain information on interfacial failure by recording video rate images of the interface as it failed, while simultaneously recording the load applied. MATERIALS AND METHODS: Fluorescent labeled adhesives were used to retain resin-based composite bobbins on the flat exposed dentin surface of teeth included in epoxy resin blocks. The teeth were secured in a miniature straining stage while the bobbins were loaded in shear mode and the interface viewed with a tandem scanning confocal microscope. Images of the interface during failure were recorded with the aid of computer image processing and storage. The dynamic failure pattern, site of failure (after repositioning the fractured bobbin under the microscope) and shear bond stress were analyzed for four dentin adhesives [OptiBond (OB), Scotchbond Multi-Purpose Plus (SBMP+), Clearfil Liner Bond 2 (CFLB2) and ESPE Bonding System (EBS)]. Control specimens without fluorescent dyes were also studied. Four dynamic patterns of failure were observed: snap, slip/stick, peel and shock wave were seen respectively with OB, SBMP+, CFLB2 and EBS adhesive. The shear bond strengths were ranked EBS*>OB>SBMP+>CFLB2* (*statistically different at alpha=0.05). No significant difference was found between specimens with and without fluorescent dye.

Acid Etching, Dental↗
PubMed2000

Effect of different single-bottle dentin adhesives on vascular responses in rat carotid artery.

PURPOSE: To investigate the effect of one-bottle dentin bonding systems on pulpal hemorrhage control in direct pulp exposures through contraction of pulp blood vessels using the rat carotid artery model. MATERIALS AND METHODS: Four dentin bonding agents (Prime & Bond 2.1, Prime & Bond NT, Syntac Single Component and Single Bond) were used. The efficacy of bonding agents were compared to that of epinephrine (control) in the viewpoint of the concentration applied and the contraction forces induced on the smooth muscle were recorded using a force displacement transducer. RESULTS: Three of the test materials produced epinephrine-like contractions on the rat carotid artery (smooth muscle) while no reading could be achieved with Single Bond. A ranking between the bonding agents for contraction forces was obtained as follows: Prime & Bond NT > Prime & Bond 2.1 > Syntac Single Component (P < 0.05).

Analysis of Variance↗
PubMed2000

Microtensile bond strength to dentin and cavity adaptation of Cerec 2 inlay restoration.

PURPOSE: To examine the bond strength of Cerec 2 inlays both to dentin surface by microtensile testing and to cavity walls by cavity adaptation in Class II restorations, using three luting materials. MATERIAL AND METHODS: VitaMark II disc was bonded to the coronal dentin surface with Clapearl DC (Clearfil DC)/Linerbond IIsigma (Linerbond 2V), AP-X/Linerbond IIsigma or Fluorocement (Panavia F)/ED Primer. After 24-hr storage in water, microtensile bond strengths (MTB) were measured. Additionally, Cerec inlays were luted to the MO cavities prepared in molars with the same materials. After thermocycling (x2000), the restorations were sectioned mesio-distally. Gap formation was microscopically examined along the cavity walls. RESULTS: There was no significant difference in MTB among the materials (Clapearl DC: 20.89 +/- 4.58 MPa, AP-X: 24.22 +/- 5.97 MPa, Fluorocement: 19.82 +/- 6.43 MPa, Scheffé, P > 0.05). The frequency of gap formation was higher in AP-X than in Clapearl DC and Fluorocement (chi2-test, P < 0.05). Debonding occurred more often at the luting material/dentin interface than at the inlay/luting material interface (Sign test, P < 0.05).

Analysis of Variance↗
PubMedDate not supplied

Mouthrinses: a comparative microbiological study.

This study was performed in order to evaluate the efficacy of different mouthrinses whose use is extended in Spain. Six different antiseptic mouthrinses were studied by means of determination of Minimal Inhibitory Concentration (MIC) values against Klebsiella pneumoniae, Serratia marcescens, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhimurium, Bacillus subtilis, Streptococcus mutans, Prevotella intermedia, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. Also in vivo experiments were carried out in volunteers by the use of mouthrinses and evaluation of bacterial populations before and after the treatment. Finally, the kinetics of bacterial death was determined. Results suggested that the determination of MIC values is not a reliable method to evaluate the antibacterial effect of such products. On the other hand those rinsing solutions based on the effect of oxygen, such as those containing carbamide peroxide have a greater efficacy against anaerobic bacteria compared with rinses whose active molecule is a disinfectant. Finally, the kinetics of bacterial death demonstrates that the essential oil rinse kills bacteria much faster. All tested mouthrinses were active as antibacterial although those based on oxygen production or essential oils were more active than solutions based on chlorhexidine and Triclosan.

Aggregatibacter actinomycetemcomitans↗
PubMedDate not supplied

Mandibular intercanine width increase without intervention in children with slipped contacts.

PURPOSE: Imperfect spacing between the primary incisors and mal-alignment of the permanent incisors may suggest the need for orthodontic intervention. Without sufficient data, decisions to treat are based on individual judgment rather than evidence. The present study was undertaken to determine whether slipped contact arrangement (distal-lingual surface of mandibular permanent lateral incisors overlapping the facial surface of the primary canines at the end of incisor transition) merits intervention. METHODS: Seventeen children who presented with slipped contact arrangement between 1987 and 1991 were studied prospectively. Orthodontic records were gathered at enrollment and following eruption of full permanent dentition with the final record being obtained in 1995. Orthodontic characteristics were recorded and mandibular anterior teeth were measured for amount of slippage, available space and differences between primary and permanent intercanine width. Data were analyzed using student's paired t-test and other tests of statistical significance. RESULTS: Mean mandibular intercanine width increased significantly at the emergence of permanent canines (2.58 mm; p=0. 001). Average slipped contact was 3.21 mm; average space deficiency between primary canines for ideally aligned permanent incisors was 3.54 mm. No correlation was found between intercanine width measurements and molar relationships, skeletal relationship, facial type or other orthodontic characteristics. CONCLUSIONS: Slipped contacts should be considered when children undergo early orthodontic treatment for crowding. An explanation of the transitional correction is provided. Continued research is needed in this area to establish evidence-based early treatment parameters.

Analysis of Variance↗
PubMedDate not supplied

The effect of midazolam premedication on discharge time in pediatric patients undergoing general anesthesia for dental restorations.

PURPOSE: The purpose of this study was to evaluate the effect of oral premedication with midazolam on recovery times of children undergoing dental restorations under general anesthesia. METHODS: The records of 106 children (1.2-11.3 years, ASA I or II) undergoing ambulatory dental restorations were randomly selected and retrospectively reviewed: 50 subjects received midazolam (M) 0.5 mg/kg orally approximately 30 minutes prior to their procedure and 56 control subjects received no premedication (C). General anesthesia consisted primarily of inhalational anesthesia. Time in the operating room (OR), post-anesthesia care unit (PACU) and same day surgery (SDS) were determined and compared between groups. RESULTS: Both groups were similar with respect to age and weight. There were no significant differences between groups in time spent in the OR, PACU or SDS (p>0.05). In a subset of children having shorter dental procedures (OR time < or =75 minutes, n=29), there remained no significant difference in discharge times between groups. CONCLUSIONS: Preoperative administration of oral midazolam does not delay discharge of children undergoing general anesthesia for dental rehabilitation.

Ambulatory Care↗
PubMed2001

Comparative efficacy and tolerability of two direct-to-consumer tooth whitening systems.

PURPOSE: To compare the clinical response of two self-directed vital bleaching systems under market use conditions. MATERIALS AND METHODS: A randomized, parallel-group clinical trial was conducted. A total of 20 healthy adults were randomized to either a 6.0% hydrogen peroxide strip-based bleaching system or a combination system involving a 10% carbamide peroxide gel in a stock tray along with an anticavity whitening dentifrice and after-bleaching whitening mouthrinse. Only the maxillary arch was bleached over a 14-day period. Subjects were evaluated at 3, 8 and 15 days. Efficacy was measured objectively using digital image analysis to derive individual color parameters (L*a*b*) and overall color change (deltaE*). RESULTS: After 14 days, the adjusted mean reduction in yellow (Ab*) was -2.23 +/- 0.157 for the whitening strips compared to -0.97 +/- 0.188 for the combination system. This represented a highly statistically significant (P< 0.0001), two-fold superior reduction in yellowness for the whitening strip group compared to the marketed control. Similar results were seen for other color parameters, with the whitening strip group exhibiting two-fold color improvement relative to the tray/dentifrice/rinse combination. With respect to tolerability, tooth sensitivity and oral irritation were the most common findings. Considering event duration and severity, median bleaching tolerability severity-days scores were 0.07 and 0.58 for the strip and combination systems respectively, with these treatments differing statistically (P= 0.04 1) favoring the whitening strips.

Adult↗
PubMed2001

Clinical evaluation of the efficacy of a battery-powered toothbrush. results from two independent studies.

PURPOSE: To compare the clinical efficacy with respect to plaque removal of a battery-operated power toothbrush (Dr. Johns Spin Brush Classic) with two manual toothbrushes, a standard ADA flat trim reference brush and the Oral-B CrossAction toothbrush. MATERIALS AND METHODS: Efficacy was evaluated in two independent studies using a randomized, single-use, cross-over design. Healthy adult subjects from a general population brushed their teeth for a timed 1 min and plaque was scored before and after brushing was completed. In Study 1 (Spin Brush vs. ADA toothbrush), plaque was scored using the modified Quigley and Hein Plaque Index, while in Study 2 (Spin Brush vs. CrossAction) plaque was scored using the Modified Navy Plaque Index. In addition, a hard and soft tissue examination was carried out before and after brushing to allow evaluation of safety. RESULTS: In Study 1, both the ADA toothbrush and the Spin Brush significantly reduced levels of whole mouth and approximal plaque (P < 0.0005); however, the Spin Brush was not significantly more effective than the manual brush. Relative plaque reduction for the whole mouth was 35.6 +/- 16.0% for the Spin Brush compared to 38.9 +/- 14.9% for the manual toothbrush (P < 0.047), and, for the approximal surfaces, 32.7 +/- 14.6% and 36.3 +/- 13.7%, respectively (P = 0.024). In Study 2, both toothbrushes significantly reduced plaque levels (P < 0.0001), but, as for Study 1, the CrossAction manual toothbrush was more effective than the Spin Brush. For whole mouth, marginal and approximal sites, respectively, the Spin Brush reduced plaque by 54.3%, 43.5% and 62.0%, compared with 58.6%, 47.5% and 67.1% for the CrossAction toothbrush. The difference in favor of the CrossAction brush was statistically significant (P < 0.0005) for all areas.

Adolescent↗
PubMed2001

Microleakage of tetric ceram/excite and Ariston pHc/Ariston liner.

PURPOSE: To investigate the microleakage associated with a hybrid resin-based composite, Tetric Ceram, bonded with the single component dentin bonding agent Excite and Ariston pHc bonded with Ariston Liner. Ariston pHc bonded with Excite and Tetric Ceram bonded with Prime and Bond NT were used as controls. MATERIALS AND METHODS: Twenty-four extracted human premolars and molars were randomly assigned to four groups. Group 1: cavities were bonded with Excite and filled with Tetric Ceram. Group 2: cavities were bonded with Ariston Liner and filled with Ariston pHc. Group 3, control: cavities were bonded with Prime & Bond NT and filled with Tetric Ceram. Group 4, control: cavities were bonded Excite and filled with Ariston pHc. Cavities were cut in both the buccal and lingual surfaces. Half of each preparation was in enamel and the other was in cementum/dentin. The teeth were thermocycled at 15 degrees C for 2 s, 35 degrees C for 28 s and 45 degrees C for 2 s for 5,000 cycles after which the restorations were examined microscopically for leakage using procion brilliant red as a marker. SEM microphotographs were prepared from dye-labeled and non dye-labeled areas to illustrate the micromorphology of the systems. RESULTS: None of the groups showed microleakage at the enamel margins. All groups showed microleakage at the gingival margins. At the gingival margin there was a significant difference between the groups (Kruskal-Wallis ANOVA, P= 0.1111.). Ariston pHc/Ariston Liner showed significantly lower microleakage scores than the other groups (Dunn's Multiple Comparison test). SEM showed that in non-dye labeled areas, Ariston pHc/Ariston Liner was in close apposition to the deeper dental tissues. The "total etch" technique resulted in a zone of demineralization. Debonding occurred at or near the top of the hybrid layer in >95% of specimens.

Acid Etching, Dental↗
PubMed2001

Effect of intrapulpal pressure simulation in vitro on shear bond strengths and hybrid layer formation.

PURPOSE: To test the hypothesis that simulation of an intrapulpal pressure during the application of dentin bonding systems influences hybrid layer formation in vitro. MATERIALS AND METHODS: 180 teeth and three different bonding agents were used for shear bond strength measurements and for confocal laser scanning microscopy studies on the dentin-composite interface. The bonding agents (30 teeth each material) were applied without (90 teeth, Group A) and with intrapulpal pressure simulation of 34 cm H20 with water (90 teeth, Group B). 45 specimens from each group were sheared in a testing machine, and 45 teeth from each group were used for CLSM studies after labeling the primer components of the bonding agents with a fluorescent dye. RESULTS: After simulation of pulpal pressure the bond strengths decreased significantly in all groups (Syntac [without/with]: 16.0 +/- 4.5/8.0 +/- 3.7, P= 0.001; Gluma: 13.3 +/- 4.6/8.4 +/- 4.4, P= 0.008; Prime & Bond NT: 14.8 +/- 5.8/8.7 +/- 5.7, P= 0.007; n = 15 each; U-tests). There were no significant differences between the hybrid layer thickness without/with simulation of pulpal pressure (Syntac: 3.6 +/- 0.6/4.1 + 1.2, P= 0.35; Gluma: 3.5 +/- 0.6/3.7 + 0.9, P= 0.49; Prime & Bond NT: 3.5 +/- 0.9/3.8 + 0.8, P= 0.44; n = 15 each; U-tests). In the case of simulation of an intrapulpal pressure, CLSM examination revealed a distinctly shallower penetration of the adhesives into dentin compared to the samples treated without intrapulpal pressure.

Acid Etching, Dental↗
PubMed2001

Porosity of resin cements and resin-modified glass-ionomers.

PURPOSE: To quantify the internal free surface in various resin cements and glass-ionomer-based materials. MATERIALS AND METHODS: Materials tested were Nexus fluid (NXF) and viscous (NXV), Vitremer (VTM), Fuji II LC (FII), Vitremer Luting Cement (VLC), Dyract (DYR) and Compoglass (COM). Samples (n=5) were made of each material between two microscopic glass slides under same weight. With a transmitted light microscopy, four zones of each sample were evaluated, finding the number of porosities per mm2 (NP), the average radius of porosities (RP), the ratio of total area of surface porosities (micron2) to area (mm2) of specimen surface (TA) and the ratio of total volume of porosities (micron2) to area (mm2) of material surface (VP). RESULTS: Median test was used. NP: NXV, NXF and DYR had smaller NP than VTM and FII and (likely) than VLC (P> 0.0000001). RP was smaller for DYR than for VLC and (likely) than for NXV (P= 0.00019). TA: NXV, NXF and DYR had smaller TA than VTM, FII and VLC (P< 0.0000001). VP: NXV and DYR had smaller VP than FII and (likely) than VTM and VLC (P< 0.0000001).

Chi-Square Distribution↗
PubMed2001

Microleakage of hydrophilic adhesive systems in Class V composite restorations.

PURPOSE: To investigate the microleakage of four hydrophilic adhesive systems: one "multiple-bottles" (Scotchbond Multi-Purpose Plus); two "one-bottle" (Single Bond, Stae); and one self-etching (Etch & Prime 3.0). MATERIALS AND METHODS: 120 bovine incisor teeth were divided into four groups (n = 30) and Class V cavities were prepared at the cemento-enamel junction. The cavities were restored with the adhesive systems and with Z100 composite. The teeth were thermocycled 1,000 times between 5+/-2 degrees C and 55+/-2 degrees C with a dwell time of 1 min, and then placed in a 2% methylene blue dye (pH 7.0) for 4 hrs, washed and sectioned vertically through the center of the restorations. The qualitative evaluation was made by three examiners who distributed pre-established scores (0-4) for each tooth using a stereomicroscope at x30 magnification. RESULTS: In enamel margins little microleakage was observed and the Kruskal-Wallis analysis did not show differences. In dentin margins the Kruskal-Wallis and multiple comparison analyses were applied: microleakage was significantly greater with Stae (median 3) and Scotchbond MP Plus (median 4). Single Bond (median 1) and Etch & Prime 3.0 (median 2) showed the best results in dentin margins, and the statistical analysis did not demonstrate differences in microleakage among these groups.

Animals↗
PubMed2001

Post-operative sensitivity in glass-ionomer versus adhesive resin-lined posterior composites.

PURPOSE: To compare objective and subjective assessments of post-operative sensitivity when class 1 cavities, lined with glass-ionomer or adhesive bonding system, were restored with resin-based composite (RBC). MATERIALS AND METHODS: Occlusal cavities on homologous contra-lateral posterior teeth in 44 male patients attending primary health centers in Riyadh, Saudi Arabia were restored with RBC after a cavity lining of either a light cured glass-ionomer cement (Vitrebond) or an adhesive bonding system (One-Step). RESULTS: Cold response measurements 24 hrs, 7 days and 1 month post-operatively showed that the threshold of pulpal response was significantly lower (P< 0.05) in the restored teeth when the adhesive bonding system served as cavity liner. In addition, based on the patients' subjective assessments, the prevalence of mild or severe post-operative sensitivity was significantly higher (P< 0.05), 24 hrs and 7 days post-operatively, in the teeth with the adhesive bonding system as a cavity liner. After a post-operative period of 1 month, however, there was no significant difference (P> 0.05) between the prevalence of post-operative sensitivity when the restored teeth received a lining of either glass-ionomer or adhesive bonding system.

Acid Etching, Dental↗
PubMed2001

Long-lasting orofacial pain--a study of 109 consecutive patients referred to a pain group.

The aim was to register and evaluate the orofacial pain condition, with special focus on the equalities/inequalities between the sexes, in consecutive patients referred to the pain group at the Centre for Oral Health Sciences in Malmö, Sweden. The 109 patients, 85 (78%) women and 24 (22%) men, were referred to the pain group during the years 1988 to 1993 and were clinically examined using a standardised procedure. Pain duration of one year or more was experienced by 83% of the patients. The pain onset was related to dental care or toothache by 56% of the patients. Temporomandibular disorders were the most common diagnoses (52%) and were more common among women than among men (p < 0.05). Multiple pain locations were frequently reported, range 1-47 locations, and the women had significantly (p < 0.05) more pain locations than the men. Equalities between the sexes were more frequent than inequalities among patients referred for long-lasting orofacial pain. It can be discussed whether the sex difference in the prevalence of pain of musculoskeletal origin emerges from biological differences or can be explained by different psychosocial circumstances.

Adult↗