Changes in abutment tooth mobility by wearing partial denture.
Explore the source record for details and available documents.
Adult↗
SEARCH · PubMed Health
Results for “Tooth Wear”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
In vitro occlusal wear of restorative materials on primary teeth.
Since primary tooth enamel wears more rapidly than permanent tooth enamel, it is important to study the mechanical wear patterns of restorative materials used in the primary dentition. It is important that an in vitro evaluation of wear resistance of different restorative materials is done in order to establish a valid in vitro test protocol for use in pediatric dentistry.
Compomers↗
Clinical wear study of three commercially available artificial tooth materials: thirty-six month results.
STATEMENT OF PROBLEM: Excessive wear of artificial resin teeth has been a concern to both the patient and the dentist because of unfavorable associated sequelae. The search for a more wear resistant resin tooth material resulted in the development of modified resin teeth that displayed acceptable wear resistance. PURPOSE: This study compared clinical wear of a new modified resin tooth material with two other commercially available modified resin materials over a period of 36 months. Differences in wear by gender, cuspal anatomy, arch, individual tooth type, and chewing side preference were also evaluated. MATERIAL AND METHODS: A total of 67 patients were randomized into one of three treatment groups in this double-blind study; group 1, Ivoclar-Vivodent and Orthotyp; group 2, Dentsply-Trublend SLM; and group 3, Dentsply-Bioblend IPN. Tooth wear was determined by measuring vertical heights of contacting points at baseline and 36 months with a computerized coordinate measuring machine and computer-controlled positioning stages. Measurements were completed at 36 months for 55 patients who remained in the study. RESULTS: Repeated measures analysis of variance revealed no significant difference in total wear by gender or tooth material at 36 months. There was also no significant difference by chewing side preference or cuspal anatomy. However, there was a significant difference in individual tooth wear (canine, premolar, molar) and by arch. CONCLUSION: New modified resin teeth have displayed clinically acceptable wear resistance for most patients.
Acrylic Resins↗
The relative importance of tooth loss and denture wearing in Swedish adults.
Having natural teeth is a matter of varying importance according to the priorities given to dental health status, compliance with recommendations and demand for dental care. The aim of this study was to assess the relative adjustment needed when one or more teeth are lost and when dentures are provided compared with other life events. The study was conducted as a mailed questionnaire to a sample of 311 20-70 year old subjects in the community of Jönköping. Seventy-five per cent of the sample, with a mean age of 43.2 years, responded. The Social Readjustment Rating Questionnaire, comprising 46 life events, was supplemented with two events concerning tooth loss and denture-wearing. The answers were given on a graphic rating scale with end points 'not difficult at all' and 'more difficult than anything' and coded by values 0 to 20. After calculation of mean values, the questions were rank ordered; the item with the highest mean was given the highest rank. 'Losing one or more teeth' was ranked 28.5 (means = 10.7) and 'getting dentures' 33 (means = 12.0) of the 48 life events investigated. This suggests that a majority of respondents perceived losing teeth and being provided with dentures as more important in terms of adjustment than events such as 'marriage', 'retirement' and 'changing work'. No significant differences in relation to age and sex were found.
Adaptation, Psychological↗
An in vitro wear study of posterior denture tooth materials on human enamel.
This in vitro study evaluated the wear effects of five posterior denture tooth materials on human enamel. The tooth specimen was cusp shaped and enamel specimen was formed as a 10 C 10 C 5 mm plate. All material-enamel combinations were tested using a machine designed to produce sliding contact 20 C 104 times at 60 cycles min-1 and a 4-mm sliding distance per stroke in the bucco-lingual direction under a load of 1 kg. Wear analysis was measured as the total height loss of each combination. In addition, the surface roughness (Ra) of each worn specimen was also evaluated. The least total height loss occurred with poly (methyl methacrylate) (PMMA) enamel pair, and the greatest did with porcelain (Po)-enamel pair. The lowest compound Ra value was measured in high-strength resin (HR)-enamel pair, and the highest in Po-enamel pair. These findings suggest that the best combination is PMMA-enamel, and the poorest combination is Po-enamel.
Acrylates↗
[A comparative study of masticatory efficiency between partial denture wearers having one remaining tooth and complete denture wears]
Masticatory efficiency is one of the important indexes of judging masticatory function after dentures restored.The aim of this study was to measure and analyze masticatory efficiency of partial dentur wearers having one tooth left and complete denture wearers,by using a method of measuring msticatory crushed granules.The results showed that the crushed granules for partial denture wearers with one remaining tooth were smaller than that for complete ones.Therefore,partial dentures with a few remaining teeth were better than complete ones on effects.
Journal Article↗
[Study on micro-hardness and wear resistance of human tooth at different depth].
Micro-hardness of human teeth was measured by micro hardnessmentry at different depths i.e. enamal, enamelo-dentinal junction and dentin. A simulated dental friction test was conducted of respectively in these three areas, opposing pure titanium ball under a modified fretting machine. The results showed that micro-hardness is 320.40 +/- 22.77 HV of enamal, 232.26 +/- 32.31 HV of enamelo-dentinal junction, and 61.17 +/- 9.42 HV of dentin (P < 0.05). Wear depth is 17.33 +/- 0.58 microns of enamal, 49.44 +/- 16.47 microns of enamelo-dentinal junction and 95.20 +/- 15.07 microns of dentin(P < 0.05). Wear resistance of enamal is much better than that of dentin's. This preliminary investigation should be very useful in clinical applications.
Adult↗
A silent period in the masseter electromyogram following tooth contact in subjects wearing full dentures.
Explore the source record for details and available documents.
Adult↗
Three-year follow-up of five posterior composites: SEM study of differential wear.
Assessing the wear of both enamel and composite at a shared occlusal contact area offers the opportunity to determine the differential wear between enamel and composite on the same tooth. Differential wear measurements were carried out on five posterior composite materials with an accurate 3D-measuring technique. The distinct wear step between enamel and composite was visualized by means of scanning electron photomicrographs. Both investigated ultrafine midway-filled and fine compact-filled composites (Willems et al., 1992a) have a considerably higher differential wear value and are, therefore, less suitable for rehabilitation of posterior teeth than are the ultrafine compact-filled composites, which have, in this study, a very satisfactory differential wear rate and appear to be highly wear resistant materials suitable for use in stress-bearing areas.
Adult↗
Posterior restorations--a clinical view.
This paper examines the state-of-the-art in the direct restoration of posterior teeth. The existing paradigms for the management of caries are questioned and some existing methods of cavity preparation are reviewed. Dental restorations need to be durable but able to adapt to a changing environment brought about by wear of the adjacent tooth substance and by fatigue processes within the tooth itself. The wear of restorative materials needs to be matched to that of the tooth, otherwise differential loss of either the restorative material or the enamel may destabilize the occlusion. Esthetic instability due to natural darkening of the tooth with age, punctuated by clinical intervention with bleaching procedures, adds a further dimension to the concept of a permanent restoration. Clinical methods that minimize the disruptive effects of dental restorations upon the remaining tooth structure are a continuing challenge.
Bicuspid↗
The impact of tooth loss in a denture wearing population: an assessment using the Oral Health Impact Profile.
OBJECTIVES: To assess the impact of tooth loss in complete denture wearers using the Oral Health Impact Profile (OHIP), and to compare the validity of 49 and 14 item versions of OHIP in a denture wearing population. DESIGN: In this cross sectional study, data were collected at Newcastle Dental Hospital, UK. Two groups were involved: (1) subjects edentulous in one or both jaws seeking dental implants to retain their intra-oral prostheses (n = 48); (2) an edentulous control group of the same age and gender distribution requesting conventional, complete dentures (n = 35). All participants in the study completed a 49 item OHIP (OHIP-49) and a validated denture satisfaction questionnaire prior to active treatment. OHIP data were computed using the weighted standardised and simple count methods. Non-parametric statistical tests were used to compare the responses of implant and control subjects. RESULTS: Both groups were dissatisfied with their conventional dentures and had relatively similar levels of dissatisfaction. There were statistically significant differences between the groups for all seven OHIP-49 sub-scale scores. Differences between OHIP-14 sub-scale scores were also significant, with presence of teeth influencing the impact on psychological discomfort. CONCLUSION: Subjects in the implant group were significantly more impaired, disabled and handicapped by tooth loss than subjects seeking conventional dentures. The results suggested that OHIP-49 and OHIP-14 had a similar ability to discriminate between the groups. This indicates that OHIP-14 may be a useful aid in a clinical setting.
Adult↗
Mechanical defenses in leaves eaten by Costa Rican howling monkeys (Alouatta palliata).
Primate species often eat foods of different physical properties. This may have implications for tooth structure and wear in those species. The purpose of this study was to examine the mechanical defenses of leaves eaten by Alouatta palliata from different social groups at Hacienda La Pacifica in Costa Rica. Leaves were sampled from the home-ranges of groups living in different microhabitats. Specimens were collected during the wet and dry seasons from the same tree, same plant part, and same degree of development as those eaten by the monkeys. The toughness of over 300 leaves was estimated using a scissors test on a Darvell mechanical tester. Toughness values were compared between social groups, seasons, and locations on the leaves using ANOVA. Representative samples of leaves were also sun-dried for subsequent scanning electron microscopy and energy dispersive x-ray (EDX) analyses in an attempt to locate silica on the leaves. Both forms of mechanical defense (toughness and silica) were found to be at work in the plants at La Pacifica. Fracture toughness varied significantly by location within single leaves, indicating that measures of fracture toughness must be standardized by location on food items. Monkeys made some food choices based on fracture toughness by avoiding the toughest parts of leaves and consuming the least tough portions. Intergroup and seasonal differences in the toughness of foods suggest that subtle differences in resource availability can have a significant impact on diet and feeding in Alouatta palliata. Intergroup differences in the incidence of silica on leaves raise the possibility of matching differences in the rates and patterns of tooth wear.
Alouatta↗
Wear of CAD/CAM ceramic inlays: restorations, opposing cusps, and luting cements.
Six standard mesio-occlusodistal restorations in extracted mandibular human molars and six opposing palatal cusps from maxillary human first molars were prepared per group. The occlusal contact areas of the restorations and of the opposing enamel cusps were digitized with a three-dimensional scanner. The specimens were exposed to a clinically correlated long-term in vitro wear test. Dicor MGC, Cerec Vita Mk I porcelain, Cerec Vita Mk II V7R porcelain, and Cerec Mk II Vita V7K porcelain were tested. The mean wear of these ceramic materials at the end of the long-term test ranged from 24.3 +/- 10.3 microns (Cerec Vita Mk II V7R) to 88.0 +/- 37.3 microns (Dicor MGC). The mean wear of the opposing human enamel cusps ranged from 93.5 +/- 30.8 microns (Cerec Vita Mk II V7R) to 224.3 +/- 117.4 microns (Cerec Vita Mk I). All ceramic materials except Dicor MGC wore less than did previously measured standards, such as natural human enamel and amalgam. However, because the wear of opposing enamel cusps was high with Dicor MGC and with Cerec Vita Mk I the total wear of these two materials--the sum of the restoration's and the opposing tooth's wear--was higher than that of the standards. Only the new fine porcelain Cerec Vita Mk II V7R showed a total wear comparable to that of enamel, because of its moderate abrasivity against opposing enamel. The wear of the two luting composite resins was measured at the end of the test. Both luting composite resins wore more than did the ceramic inlays and surrounding enamel, leaving a shallow ditch around the restorations.
Ceramics↗
Wear of dental tissues and materials.
Wear may result from physiological or pathological conditions and may be desirable, as in the reduction of an overcontoured restoration, or undesirable as in the production of cervical abrasion cavities. A variety of methods, including clinical testing, the use of wear machines and the measurement of related properties such as hardness or coefficient of friction have been used to investigate wear of tooth tissue and of dental materials. Because these methods may not reveal the nature of the wear process recent work has been directed to the study of surface failure resulting from a single sliding contact. Many clinical studies have been conducted but they are time consuming and difficult to quantify, nor do they allow of evaluation of different parameters contributing to the wear. Laboratory simulation of wear has been shown to be valuable in comparing materials of the same group but between-group comparisons may give anomalous results. The most rewarding studies have been those using a single or small number of passes of a suitable abrading point over the material since these permit determination of the actual process by which wear is produced.
Acrylic Resins↗
Spatial and functional modeling of carnivore and insectivore molariform teeth.
The interaction between the two main competing geometric determinants of teeth (the geometry of function and the geometry of occlusion) were investigated through the construction of three-dimensional spatial models of several mammalian tooth forms (carnassial, insectivore premolar, zalambdodont, dilambdodont, and tribosphenic). These models aim to emulate the shape and function of mammalian teeth. The geometric principles of occlusion relating to single- and double-crested teeth are reviewed. Function was considered using engineering principles that relate tooth shape to function. Substantial similarity between the models and mammalian teeth were achieved. Differences between the two indicate the influence of tooth strength, geometric relations between upper and lower teeth (including the presence of the protocone), and wear on tooth morphology. The concept of "autocclusion" is expanded to include any morphological features that ensure proper alignment of cusps on the same tooth and other teeth in the tooth row. It is concluded that the tooth forms examined are auto-aligning, and do not require additional morphological guides for correct alignment. The model of therian molars constructed by Crompton and Sita-Lumsden ([1970] Nature 227:197-199) is reconstructed in 3D space to show that their hypothesis of crest geometry is erroneous, and that their model is a special case of a more general class of models.
Animals↗
Wear rates of artificial denture teeth opposed by natural dentition.
The wear rate of polymeric or composite-based artificial denture teeth on fixed, removable and implant prostheses is important in the maintenance of cuspal form, masticatory efficiency and occlusal stability. A servo-hydraulic based artificial mouth in which an occlusion was established between artificial denture teeth, and the palatal cusp of a human maxillary third molar was established and used to assess the wear resistance of 5 artificial denture tooth materials. Volumetric wear was determined for Dentsply Trublend SLM, Dentsply IPN, Vita Vitapan, Ivoclar Orthotyp and Ivoclar Orthosit denture teeth. Scanning electron microscopy was also done to assess the textural character of the wear facets of each denture tooth sample. The lowest volume loss was observed for Trublend SLM followed by IPN, Orthotyp, Vitapan and Orthosit. Textural assessment of the materials was consistent with the objective wear data.
Acrylic Resins↗
Wear rates of various artificial tooth materials: a literature review.
Current artificial tooth materials include acrylic resin, improved resin, filled polyurethane dimethacrylate, and porcelain. The improved materials have been popularized by their ability to resist abrasion. A wide variety of abrasives, measuring instruments, and methods of wear testing make it difficult to assess study results that compare these materials. Clinical trials are needed to help establish a standard laboratory test.
Dental Materials↗
A semiquantitative method of recording experimental tooth erosion and estimating occlusal wear in the rat.
As the erosive agent, a sport-drink mixture with pH 3.2 was given to Osborne-Mendel rats for 6 weeks. Lingual surfaces of the right first mandibular molar crowns were chosen for the recording. With the aid of a drawing tube mounted on a stereomicroscope, enlarged drawings of the surfaces were made encircling the intact and eroded areas. A computer-coupled analyser was used to measure the areas of the total surface, intact surface, eroded enamel and exposed dentine in square millimetres. The data was evaluated statistically and used to calculate erosion changes and to estimate occlusal wear.
Animals↗