Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TOOTH ABRASION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,189 records · Page 66Linked to original sources

Enamel structure and microwear: an experimental study of the response of enamel to shearing force.

The anisotropic fracturing and differential wear properties of enamel microstructure represent factors that can obscure the predictive relationship between dental microwear and diet. To assess the impact of enamel structure on microwear, this in vitro experimental study examines the relative contributions to wear of three factors: 1) species differences in microstructure, 2) direction of shearing force relative to enamel prisms and crystallites, and 3) size of abrasive particles. Teeth of Lemur, Ovis, Homo, and Crocodylus, representing, respectively, the structural categories of prismatic patterns 1, 2, and 3 and nonprismatic enamel, were abraded by shearing forces (forces having a component directed parallel to abraded surfaces) and examined by scanning electron microscopy. Striation width increased with particle size for nonprismatic, but not for prismatic, specimens. Direction of shear relative to prism and crystallite orientation had a significant influence on striation width in only some prismatic enamels. The different responses of prismatic and nonprismatic enamels to abrasion reflect the influence of structure, but at the level of organization of crystallites rather than prisms per se. Such interactions explain in part the inability of striation width to discriminate among animals with different dietary habits. Heteroscedasticity and deviations from normality also may confound parametric analyses of microwear variables. Variation in crystallite orientation in prismatic enamels may contribute to optimal dental function through the property of differential wear in functionally distinct regions of teeth.

Alligators and Crocodiles↗

Plaque accumulations caused by interdental stripping.

Human enamel surfaces were stripped with orthodontic grinding and finishing materials, and evaluated with the scanning electron microscope (SEM). Even under in vitro conditions with the finest finishing strips, it was not possible to produce an enamel surface free of the furrows that result from the initial abrasion caused by the coarse strip. Enamel surfaces stripped gradually from coarse to superfine were left in the mouths of patients for 12 weeks and evaluated with the SEM. The edges of the furrows were found to be smoother but the furrows remained wide and deep enough to facilitate more plaque accumulations than those on untreated surfaces. The use of dental floss did not result in prevention of plaque accumulations along the bottom of the furrows.

Dental Enamel↗

[Abrasion measurements in vivo in occlusal composite and amalgam fillings].

A new method for quantitative measurement of occlusal wear on restorations is described. In a clinical evaluation with four different composites and an amalgam the method proved to be simple in execution and very exact. Statistical analysis after 7 months has shown significant differences in wear resistance of the different materials. The nature of the resulting wear was electron optically examined. Typical structural surface characteristics were observed for each of the different materials. More recently developed composities utilizing extremly small filler particles (Aerosil) seem to be comparable to amalgam in wear resistance.

Adult↗

A comparison of the abrasiveness of six ceramic surfaces and gold.

A type III gold alloy and six different ceramic surfaces were secured in an abrasion machine opposing extracted teeth to determine their relative abrasiveness and resistance to wear. The rankings of restorative materials from least abrasive to most abrasive were: gold alloy, polished; cast ceramic, polished; porcelain, polished; cast ceramic, polished and shaded; porcelain, polished and glazed; cast ceramic, cerammed skin shaded; and cast ceramic, cerammed skin unshaded. The ranking of materials from most wear-resistant to least wear-resistant was: gold alloy, cast ceramic cerammed, cast ceramic cerammed and shaded, porcelain polished, porcelain glazed, cast ceramic polished and shaded, and cast ceramic polished.

Analysis of Variance↗

A comparison of electric toothbrushes in their potential to cause gingival abrasion of oral soft tissues.

PURPOSE: It has previously been established that gingival abrasion associated with the Braun Oral-B Ultra Plaque Remover (D9) is minimal and comparable to that observed with a manual toothbrush. The purpose of this single-use study was to compare gingival abrasion with the D9 and a novel electric toothbrush, the Braun Oral-B 3D Plaque Remover (3D). MATERIALS AND METHODS: 49 subjects (non-dental students) with at least 24 natural teeth and an absence of periodontal probing depths of 5 mm or greater were included in this study. Following a familiarization phase, all subjects received a single prophylaxis and were asked not to brush their teeth for 24 hours prior to their appointment. At this visit, the gums were disclosed by Mira-2-Tone solution and all gingival abrasion on the soft tissues was assessed and recorded. Subjects then brushed their teeth in a random split-mouth order with the two electric toothbrushes, using brush heads of the same design (EB9). The gums were then re-disclosed and gingival abrasions were recorded. They were recorded as either small sites of abrasion (< or = 5 mm) or large sites of abrasion (> 5 mm). RESULTS: The mean number of small traumas increased from 2.57 at baseline to 4.04 after brushing with the D9 and from 1.98 to 4.14 after brushing with the 3D. There was no statistically significant difference between the two groups. For both toothbrushes, more small traumas were found in the upper jaw compared with the lower jaw. No increase in number of large traumas was observed.

Adolescent↗

One-year clinical performance of PMDM-based dentine bonding agents.

Two PMDM-based dentine bonding agents and a microfilled composite were used to restore a total of forty non-undercut caries-free cervical abrasion lesions without enamel etching. Restorations were evaluated over one year and the loss rate calculated using a life table analysis. Marginal staining was assessed from colour photographs on a continuous linear rating scale. After one year, 5 per cent of Tenure bonded restorations were lost compared with 52 per cent of Mirage bonded restorations. Slight marginal staining was evident around Tenure bonded restorations after one year.

Adult↗

One-year clinical evaluation of three dentine bonding agents.

One hundred and twenty-five composite restorations were placed in non-undercut, non-enamel-etched Class V abrasion lesions in 20 patients using the dentine bonding agents Scotchbond 2, Tripton, and Prisma Universal Bond 2. Patients were recalled at approximately 3 months, 6 months, and 1 year. After 1 year the cumulative per cent survival of restorations was Scotchbond 2, 8 per cent; Scotchbond 2 with dentine roughening, 16 per cent; Tripton, 16 per cent; Prisma Universal Bond 2, 75 per cent.

Age Factors↗

[Orthodontic treatment in the distal displacement of the mandible].

A total of 598 patients with various occlusions and dentition defects were examined; 112 (18.7%) of these presented with distal dislocation of the mandible. Shortening of interalveolar distance was found to play an important role in the pathogenesis of this dislocation. This shortening occurs in abnormal teeth abrasion and loss of many molars and premolars maintaining the occlusion height. Masticatory function was found disordered in 56 (50% of patients with distal dislocation of the mandible. Orthodontic treatment of these patients was carried out by sagittal shift of the mandible to a distance of 1 to 2 mm and subsequent fitting with prostheses. Good results were attained in 94.55% of cases.

Adult↗

Hard tissue abrasivity of an automatic interdental plaque remover.

This laboratory study was conducted to assess the safety of a new interdental cleaner, the Braun Oral-B Interclean (ID2), by measuring its abrasivity to dentin and comparing this with the abrasivity of a standard ADA manual toothbrush when used with and without dentifrice. Dentin abrasion was measured by a radioactive technique, using a modified ADA-recommended methodology. Dentin specimens to be used with the ID2 had a 2 mm hole drilled through them to represent the interproximal space, whereas dentin slabs were used in the toothbrush abrasivity tests. All specimens were placed in a controlled neutron flux. The dentin specimens were then immersed either in an abrasive dentifrice (Crest) slurry or a non-abrasive (water) solution, and an 8.5 minute treatment carried out. After testing, samples of treatment slurry or solution were put in a scintillation counter and mean net counts per minute (cpm) per gram of slurry or solution were calculated. With Crest dentifrice, the ID2 removed significantly less (p < or = 0.05) dentin (232 cpm/g) than the ADA reference manual toothbrush (789 cpm/g). Without dentifrice, neither the ID2 nor the manual toothbrush removed significant amounts of dentin, and dentin loss was similar for both devices.

Analysis of Variance↗

Variability of clinical dentin substrates.

Clinical trials remain the only conclusive research of dentin adhesive performance, but variables unique to the oral environment may influence the results. Dentin variability is one factor that may account for extreme variations in clinical evaluations. Despite the encouraging results of laboratory studies, clinical trials with adhesive systems have been disappointing. Current adhesives are reported to react with dentin surfaces by chemical and/or micro-mechanical mechanisms. Dentin surfaces, such as cervical abrasions, are subject to intraoral changes and dentin tubules commonly become obturated by the growth of peritubular dentin or by the precipitation of calcific deposits within the tubules. The resulting sclerotic dentin may be less receptive to current dentin adhesives. An examination of clinically aged dentin surfaces has revealed an inordinate variability in tubular morphology. The more sclerotic dentin present, the less effective was dentin conditioning and resin composite adaptation. Early correlations with current clinical trials appear to substantiate that the greatest failure of restorations occurred in sclerotic lesions.

Aging↗

An in vitro investigation into the wear effects of unglazed, glazed, and polished porcelain on human enamel.

Abrasive wear tests were performed on unglazed, glazed, and polished porcelain stud specimens using human enamel as the opposing plate specimens. The wear tests were carried out on a wear machine that was specifically designed to simulate the masticatory cycle. The amount of enamel wear produced by both glazed and unglazed porcelain was similar; however, that produced by polished porcelain was substantially less. Investigation of the glazed porcelain surface showed that the glaze was removed in less than 2 hours of wear on the machine.

Dental Enamel↗

Clinical evaluation of five adhesive systems: three-year results.

Five dentine adhesive systems (four resin-based dentine bonding agents and one polyacid-modified composite resin) were evaluated clinically in non-undercut Class V 'abrasion' lesions. The loss rate of restorations varied from 26 per cent to 95 per cent at three years among the five systems. Products which bonded to dentine via the hybrid layer were markedly more retentive than those which were designed to bond chemically. The two products which attempted to achieve bonding between their carboxyl groups and dentinal calcium were hydrophilic, which probably contributed to their lack of success.

Acid Etching, Dental↗

Three-year clinical evaluation of dentine bonding agents.

Eighty Class V non-undercut cervical abrasion lesions were restored using four dentine bonding agents and composite resin. The restorations were examined over a three-year period, and the cumulative loss rate calculated each year. Marginal staining at each year was assessed using a standardized photographic method. The loss rate of restorations increased generally over the three-year period, reaching 30 to 60 per cent for the four products. Marginal staining also increased for all four products over the three-year period.

Adhesives↗

Polymeric adhesion to dentin: contrasting substrates.

Clinical research has shown that resin dentin adhesive materials often fail prematurely despite encouraging laboratory-derived data. Current adhesives are reported to react with dentin surfaces by chemical and/or micro-mechanical mechanisms. The ionic bonding to calcium and the covalent coupling to collagen are representative chemical strategies employed today. Recent findings suggest that the mechanical interlocking of resins into open dentinal tubules may play an even more important role with present adhesive systems. Dentin surfaces, such as cervical abrasions, undergo changes in the oral cavity and dentinal tubules may become partially or completely obturated by the growth of peritubular dentin or by the precipitation of mineral salts within the tubules. The resulting sclerotic dentin may be less receptive to current dentin adhesives. An examination of clinically aged dentin surface types revealed extreme variability in tubular morphology. The more sclerotic dentin presented, the less effective was dentin conditioning and resin adaptation. Early correlations with ongoing clinical trials appear to substantiate this finding with the greatest failure of restorations occurring in more sclerotic lesions.

Adhesives↗

A resin-modified glass ionomer restorative: three-year clinical results.

Resin modified glass ionomer (RMGI) restorative materials have gained popularity in recent years. Their use is most often indicated in Class III and Class V cavities in adults and in numerous applications in children. This popularity in use has taken place in the absence of scientific knowledge of the RMGI materials. Lacking are adequate clinical trials to validate the proposed indications. The purpose of this study was to examine a representative RMGI in cervical abrasions and root caries in adults. Patients were recalled up to three years to evaluate standard clinical criteria. Results found the RMGI to be inferior to conventional composite resin in similar applications. The most noted deficiencies were in color stability and anatomic form, or wear of the RMGI. The results of this prospective clinical trial would suggest a limited longevity for RMGI compared to traditional restorative materials. This study also reinforces the need for evidence of clinical performance prior to making decisions regarding material selections.

Adult↗

Factors affecting enamel and ceramic wear: a literature review.

Enamel wear by ceramics may adversely affect maintenance of the vertical dimension of occlusion and can increase the potential for thermal sensitivity. In this article, factors related to the abrasion of enamel by dental ceramics are critically reviewed. Concepts of physical, microstructural, chemical, and surface characteristics of dental ceramics on wear are presented based on research published since 1950. A PubMed search for key words (wear of enamel and ceramic) was supplemented with a hand search to identify relevant peer-reviewed articles published in English. Based on the literature, it can be concluded that material factors, their proper handling, and control of the patient's intrinsic risk factors related to wear are critically important to the reduction of enamel wear by dental ceramics.

Crystallization↗

[Polishing of composite resins. Instrumental notes].

BACKGROUND: The polishing is the last procedure in the application of composite fillings. The surface morphology and the marginal seal, that are indispensable for integration of composite fillings with dental tissue and oral environment, are tightly dependent on polishing procedure. METHODS: The authors tried out experimental therapeutic procedure in order to examine the surface of any composite resin polymerizated under matrix on a slide before and after polishing made by abrasive disease and finally after application of a new resin layer on a polished composite surface. These composite surfaces was examined with AFM and SEM. RESULTS: The images prove that in the polished specimens there is a restoration of composite morphology surface because of the partial removal of organic part during the polishing. The polymerization of a new resin layer on polished surface make this one more regular and even as a substitute for partial removal of organic part during the polishing. CONCLUSIONS: The experimental procedure prove that the ideal composite surface is that polymerizated under matrix because every treatment on this surface affect the composite filling's quality.

Composite Resins↗

[The characteristics of the design and use of metal-ceramic dentures in pathological abrasion of the hard dental tissues].

A total of 416 patients aged 40 to 60 suffering from abnormal teeth abrasion were fitted with cermet dentures. Orthodontic treatment was preceded by therapeutic and surgical preparation of the teeth and periodontium and by functional and adaptation rearrangement of the maxillodental system, if indicated. Remote results were assessed after 2 to 12 years. Due to such preparation good results were attained in 95.9% patients. Complications were observed in only 4.1%: exacerbation of periodontitis, ceramic facing chipping off, insertion of abutment teeth, and functional overload of the periodontium.

Adult↗