bluuebunny/crossref_metadata_2025 huggingface dataset:
Fear for the family has negative consequences: indirect effects of nest predators on chick growth in a farmland bird
Authors: Dunn Jenny C. , Hamer Keith C. , Benton Tim G.
Published: August 2010

1. The management of habitat structure can limit access to food and can also alter perceived predation risk. Minimising the risk of predation, by changing behaviour, may have negative impacts similar to predation itself across a wide range of species. Predation risk influences the behaviour of adults foraging for altricial young, so that they avoid disclosing the location of their offspring to predators. The consequences of these behavioural changes for offspring are unknown.

2. We investigate whether predator‐induced changes in provisioning rates can have impacts upon avian nestlings through reductions in growth and condition, and whether this is influenced by resource availability, using the declining yellowhammer Emberiza citrinella as a model species.

3. We show a sizeable negative impact of nest predator activity upon brood provisioning rate, indicating that parents can assess nest predation risk and adjust their behaviour accordingly.

4. Chick condition and growth were both negatively influenced by corvid nest predator abundance and positively influenced by food abundance in large broods, suggesting that parents raising large broods in unfavourable conditions were unable to compensate fully for the effect of corvid activity on provisioning rate.

5. In areas of low food availability, corvid abundance was associated with reduced chick growth and condition; in areas of higher food availability no association was found indicating that where food resources are abundant, parents can compensate for reductions in provisioning rate when corvids are active, with no long‐term implications for chicks.

6. Synthesis and applications. We propose a mechanism by which two distinct trends linked with the intensification of agriculture, namely increasing corvid abundance combined with a decreasing food supply, may have indirectly precipitated population declines in farmland passerines through delayed life‐history effects across generations. As the impacts of corvids are reduced where invertebrates are abundant, we suggest that management should concentrate on improving the quality of foraging habitat by creating mosaics of long and short vegetation, rather than on the control of corvids. This will allow adult birds to compensate for the indirect effects of high corvid abundance by increasing their provisioning effort when nest predation risk is low and thus buffer any long‐term consequences for nestlings.
The Attitudes to Disability Scale (ADS): development and psychometric properties
Authors: Power M. J. , Green A. M. ,   THE WHOQOL‐DIS Group
Published: August 2010

Background  This paper describes the development of an Attitudes to Disability Scale for use with adults with physical or intellectual disabilities (ID). The aim of the research was to design a scale that could be used to assess the personal attitudes of individuals with either physical or ID.

Method  The measure was derived following standard WHOQOL methodology as part of an international trial. In the pilot phase of the study, 12 centres from around the world carried out focus groups with people with physical disabilities, people with ID, with their carers, and with relevant professionals in order to identify themes relevant for attitudes to disability. Items generated from the focus groups were then tested in a pilot study with 1400 respondents from 15 different centres worldwide, with items being tested and reduced using both classical and modern psychometric methods. A field trial study was then carried out with 3772 respondents, again with the use of both classical and modern psychometric methods.

Results  The outcome of the second round of data collection and analysis is a 16‐item scale that can be used for assessment of attitudes to disability in physically or intellectually disabled people and in healthy respondents.

Conclusions  The Attitudes to Disability Scale is a new psychometrically sound scale that can be used to assess attitudes in both physically and intellectually disabled groups. The scale is also available in both personal and general forms and in a number of different language versions.
Involvement of Brain‐Derived Neurotrophic Factor and Neurogenesis in Oestradiol Neuroprotection of the Hippocampus of Hypertensive Rats
Authors: Pietranera L. , Lima A. , Roig P. , De Nicola A. F.
Published: August 2010

The hippocampus of spontaneously hypertensive rats (SHR) and deoxycorticosterone (DOCA)‐salt hypertensive rats shows decreased cell proliferation and astrogliosis as well as a reduced number of hilar cells. These defects are corrected after administration of 17β‐oestradiol (E2) for 2 weeks. The present work investigated whether E2 treatment of SHR and of hypertensive DOCA‐salt male rats modulated the expression of brain‐derived neurotrophic factor (BDNF), a neurotrophin involved in hippocampal neurogenesis. The neurogenic response to E2 was simultaneously determined by counting the number of doublecortin‐immunopositive immature neurones in the subgranular zone of the dentate gyrus. Both hypertensive models showed decreased expression of BDNF mRNA in the granular zone of the dentate gyrus, without changes in CA1 or CA3 pyramidal cell layers, decreased BDNF protein levels in whole hippocampal tissue, low density of doublecortin (DCX)‐positive immature neurones in the subgranule zone and decreased length of DCX+ neurites in the dentate gyrus. After s.c. implantation of a single E2 pellet for 2 weeks, BDNF mRNA in the dentate gyrus, BDNF protein in whole hippocampus, DCX immunopositive cells and the length of DCX+ neurites were significantly raised in both SHR and DOCA‐salt‐treated rats. These results indicate that: (i) low BDNF expression and deficient neurogenesis distinguished the hippocampus of SHR and DOCA‐salt hypertensive rats and (ii) E2 was able to normalise these biologically important functions in the hippocampus of hypertensive animals.
Streptococcal adherence to uncoated and saliva‐coated restoratives
Authors: SATOU J. , FUKUNAGA A. , MORIKAWA A. , MATSUMAE I. , SATOU N. , SHINTANI H.
Published: August 2010

The adherence of Streptococcus sanguis and S. mutans to seven restoratives in the presence and absence of an artificial salivary pellicle has been investigated. The physicochemical surface characteristics of the bacteria and of the restoratives were also measured, together with the effect of salivary coating of restoratives. Zeta potential of uncoated restoratives showed a positive correlation with the number of adherent S. mutans cells and S. sanguis cells. S. sanguis showed a positive correlation with the hydrophobicity of uncoated restoratives. The surface hydrophobicity was decreased upon saliva coating, whereas the zeta potential was slightly increased. The contact angles or zeta potentials of saliva‐coated restoratives were positively correlated with those of uncoated restoratives. The number of adherent cells of both S. sanguis and S. mutans to saliva‐coated restoratives were decreased after the coating. Zeta potential of saliva‐coated restoratives showed a positive correlation with the numbers of adherent S. mutans cells, suggesting that non‐specific electrostatic interactions have an important role in the adherence of this species.
Parapulpal pins and their effects on the fracture resistance of pin‐retained cores
Authors: HALLER B. , GÖTZE W. , WEISS G.
Published: August 2010

The bending characteristics of various parapulpal pins, the retention of a parapulpal pin in different core buildup materials, and the fracture resistance of pin‐retained cores were investigated in an in‐vitro study. In amalgam and composite cores, the use of parapulpal pins produced an increase in fracture resistance. The highest fracture resistance values were observed in amalgam cores, and the lowest fracture strength was exhibited by cores of glass ionomer cements (GICs) containing metallic particles. The different parapulpal pins and their flexural rigidity had little effect on the fracture resistance of the pin‐retained cores. For extensive pin‐retained cores it appears advisable to use GICs with restraint and, particularly in the case of large‐scale bridge reconstructions, only after critical examination of the loading conditions.
Craniomandibular dysfunction: patient characteristics related to treatment outcome
Authors: DE LEEUW J.R.J. , ROS W.J.G. , STEENKS M.H. , LOBBEZOO‐SCHOLTE A.M. , BOSMAN F. , WINNUBST J.A.M.
Published: August 2010

In a previous study it was concluded that only a few changes in symptoms related to craniomandibular dysfunction (CMD) could be attributed to therapy. It was suggested that psychosocial and socio‐demographic variables, as well as symptom characteristics, could be responsible for the unconvincing treatment outcome in patients treated with a splint. The present study was performed to investigate whether socio‐demographic characteristics, symptom characteristics and various psychosocial variables are associated with treatment outcome in patients with CMD treated with a splint. Treatment outcome was determined by using self‐reported follow‐up data. Results showed that patients with a negative treatment outcome were older, reported more and more severe symptoms and correlates of CMD, reported fewer stressors and more frequently considered health to be determined by external factors than patients who were treated successfully. The two groups could not be differentiated with regard to anxiety and depression. Results are interpreted with regard to the prediction of treatment outcome.
Canine tooth guidance and temporomandibular joint sounds in non‐patients and patients
Authors: DONEGAN S.J. , CHRISTENSEN L.V. , McKAY D.C.
Published: August 2010

summary
In 46 non‐patients and 46 patients, the authors examined the presence (+) and absence (‐) of canine tooth guidance (CG), i.e. dynamic dental articulation events in contrast to static dental occlusion events. During a right and a left laterotrusion of the mandible, the number of simple, mutually exclusive and exhaustive tooth guidance events (possibilities) was four. In addition, the authors examined the associations between temporomandibular joint (TMJ) sounds and canine guidance events. In non‐patients, CG+ was relatively infrequent (30%), and CG‐ was relatively frequent (70%). In patients, CG+ was relatively infrequent (22%), and CG‐ was relatively frequent (78%). In both non‐patients and patients, bilateral CG+ was rather infrequent (15%). In both nonpatients and patients with the presence of TMJ sounds, CG+ was relatively infrequent (38%) while CG‐ was relatively frequent (61%). In non‐patients as well as patients, no evidence was found that distal CG+ (putative lateral retrusive guidance) was associated with ipsilateral TMJ sounds (relative risk = 0%), nor that the association between mesial CG+ (putative lateral protrusive guidance) and ipsilateral TMJ sounds was beyond that of mere chance (relative risk = 50%).
The influence of alloy composition and casting procedure upon the corrosion behaviour of dental alloys: an in vitro study
Authors: MÜLDERS C. , DARWISH M. , HOLZE R.
Published: August 2010

summary
The influence of the composition and the casting process upon the electrochemical corrosion of a selection of palladium‐based alloys and nonprecious metal alloys has been investigated in vitro using an electrochemical method. No influence of the casting process upon the corrosion resistance was observed with palladium‐based alloys. Changes in the crystallographic structure effected by the different composition of the alloys were found, the casting process did not cause significant effects. With nickel‐chromium alloys rather low corrosion stabilities were observed.
Effect of alloy surface composition on release of elements from dental casting alloys
Authors: WATAHA J.C. , MALCOLM C.T.
Published: August 2010

SUMMARY
The release of elements from dental casting alloys is a continuing concern because of the potentially harmful biological effects the elements may have on local tissues. The surfaces of the alloys appear to be most important in controlling the release of these elements. In the current study, the surfaces of high‐, reduced‐, and no‐gold dental alloys were analysed by X‐ray photoelectron spectroscopy before and after they were exposed to a biological medium for up to 96 h. The goal was to relate the release of elements from these alloys to their surface composition, and to determine the depth of the effect of the medium. The depth of the effect of the exposure was determined by argon milling of the alloy surface after exposure to the medium. Elements that were released into the medium were measured by means of atomic absorption spectroscopy. The release of elements from alloys was greater when the atomic ratio of noble to non‐noble elements at the surface was less than 1. The depth of the effect of the medium varied with the alloy, but was always less than 100 Å. The surface composition was significantly different from layers only 5 Å below. It was concluded that the surface concentration of noble elements is important in controlling the release of non‐noble elements from these alloys, and the surface composition appeared to be only one or two atomic layers thick. of the three types of alloys, the high‐gold alloy appeared to develop the most stable surface composition which released the lowest levels of elements.
Occlusal contacts in maximum intercuspation in normal dentitions
Authors: MCDEVITT W.E. , WARRETH A.A.
Published: August 2010

summary
A cross‐sectional study of the contacts in maximum intercuspation was undertaken using a method to identify occlusal contacts, which is indicated as satisfactory by modern research. The aims were to describe in subjects with normal dentitions and normally functioning masticatory systems: (a) the general distribution of contacts; (b) the numbers in the various classes and types of occlusal contacts; (c) the numbers of teeth without contact. A randomized sample of 18 women and 20 men was used. Classical theoretical proposals for the numbers, distribution and nature of occlusal contacts were not supported. Wide variability was evident and asymmetry of distribution on the right and left sides of individual subjects was common. Contacts with stabilizing tendencies involved the mandibular supporting cusps in 79% of occurrences. Overall, the difference in the number of contacts with stabilizing effects was not significantly different from the number with unstabilizing tendencies. Contacts with mechanically unstabilizing effects did not produce clinically discernible, unfavourable sequelae in the dentitions. Because of the sparse number of stabilizing contacts, interventions involving the occlusal surfaces should maintain or improve on the number of such contacts in maximum intercuspation.
Bilateral coronoid hyperplasia–a report with a view on its management
Authors: LOH H.S. , LING S.Y. , LIAN C.B. , SHANMUHASUNTHARAM P.
Published: August 2010

summary
Bilateral coronoid hyperplasia requires surgery (coronoidectomy) to improve mouth opening. An intra‐oral approach is preferred with direct fibre‐optic anaesthetic intubation. Myotomy of the masseter muscle is recommended in cases where fibrotic and calcifying effects have occurred. Pre‐operative physiotherapy counselling and post‐operative jaw exercises are important to the final success of the management.
Splinting osseointegrated implants and natural teeth in rehabilitation of partially edentulous patients. Part I: Laboratory and clinical studies
Authors: GROSS M. , LAUFER B.‐Z.
Published: August 2010

summary
A significant clinical consideration in the restoration of partial edentulism with implant and tooth‐supported prostheses is whether implants and natural teeth abutments should be splinted, and if so, in what manner. This article presents a review of laboratory and clinical studies related to splinting. Stress analysis studies reveal high stress concentration around the implant neck when rigidly connected to teeth. This was not borne out in in vivo studies in short‐span bridges. While stress absorbing elements have been advocated to redistribute and reduce stress concentration away from the implant neck where bone resorption is often seen, finite element analysis and photo‐elastic studies demonstrate that such stress absorbing elements may be effective only when their resiliency is in the same order of magnitude as the periodontal ligament. Clinical studies reporting life table statistics in combined implant and tooth restorations do not show adverse effects of splinting teeth to implants. These studies, however, are mostly short‐term reports oh survival with results that are as yet inconclusive. The issue of connecting with rigid or non‐rigid connectors remains unresolved with a growing body of information favouring retrievable short‐span rigid connection to non‐mobile teeth. Root intrusion is a potential clinical hazard of non‐rigid connection.
Remaining mandibular third molars in an adult population
Authors: YAMAOKA M. , FURUSAWA K. , TAMBO A. , IMAI S.
Published: August 2010

summary
Although tooth loss with age has been extensively investigated, there appears to be no literature on the relationship of age to remaining mandibular third molars. The study showed that as age increases so does the frequency of absent vertically erupted mandibular third molars. However, no correlation was found between age and loss of mandibular impacted third molars in men of 71 years of age or older. The evidence presented here suggests that impacted mandibular third molars, which have not been infected, may be more likely to remain compared with other teeth at potential risk.
A comparative study of flexible (Polyactive®) versus rigid (hydroxylapatite) permucosal dental implants. II. Histological aspects
Authors: MEIJER G.J. , DALMEIJER R.A. , DE PUTTER C. , VAN BLITTERS WIJK C.A.
Published: August 2010

summary
Of the many materials that are applied in dental implantology, most have a high Young's modulus. In the concept of osseointegration, which is generally preferred, chewing forces are therefore directly transmitted from rigid implant materials to the relatively flexible surrounding bone. Polyactive® is an elastomeric polyethylene‐oxide polybutylene‐terephthalate (PEO:PBT) copolymer, with a low modulus of elasticity, that exhibits bone‐bonding characteristics. Previous finite‐element analysis emphasized the benefit of the application of flexible implant materials. To assess the validity of this finite element model, one dense and two porous types of flexible Polyactive® permucosal dental implants and one rigid hydroxylapatite (HA) implant were clinically tested in a beagle dog study and were compared during 30 weeks of loading. In an earlier report, it was concluded that dense Polyactive® implants function clinically adequately and resemble the mobility of natural teeth. In the current study, the amount of bone contact was quantitatively assessed. Polyactive® implants showed a statistically significantly higher bone contact, as compared to the HA implants, probably due to a significant water uptake and a subsequent increase in the volume of the denser Polyactive®. Morphological analysis, based on back‐scatter electron microscopy and light microscopy, revealed little remodelling activity of the bone surrounding the Polyactive® implants. Few remodelling lacunae were seen and de novo bone formation was rarely observed. At some locations, a continuity between calcification zones with the polymer surface and the surrounding interfacial bone was observed, indicating the occurrence of bone‐bonding. Also, the bone surrounding the HA implants showed little remodelling activity, although large resorption lacunae were observed, in which HA particles were present. Based on the observations of this study, flexible bone bonding implants might be more capable of transferring stresses to the surrounding bone and are therefore promising alternatives to ‘routine’ rigid implants.
Cephalometric evaluation of maxillary complete, mandibular fixed‐removable partial prosthesis:a 5‐year longitudinal study
Authors: ÜÇTAŞLI S. , HASANREİSOğLU U. , İŞERi̇ H.
Published: August 2010

summary
Lateral cephalometric films were obtained from 10 subjects treated with maxillary complete dentures opposed to bar‐supported mandibular removable partial dentures. The amount of bone resorption was determined following a 5‐year period of denture use. In the maxilla, slight resorption was observed; a considerable amount had taken place in the mandible. Comparing the results of previous studies with the present one, it is suggested that bar‐supported mandibular free‐end saddle partial denture design has beneficial effects in terms of reduced bone resorption.
Effect of fluoride treatment on remineralization of bleached enamel
Authors: ATTIN T. , KIELBASSA A.M. , SCHWANENBERG M. , HELLWIG E.
Published: August 2010

summary
The objective of the study was to evaluate the remineralizing capacity of different fluoride treatments on dental enamel bleached with carbamide peroxide (Opalescence®). Sixty bovine enamel slabs were subjected to four cycles comprising bleaching (12 h) and remineralization in artificial saliva (8 h). The samples were evenly distributed among four groups (A‐D). During the first hour of the remineralization period the specimens in group A were covered with a fluoride varnish (Duraphat®; 2.23% F−). In group B the enamel slabs were stored in a fluoride solution (0.2% F− as NaF) for 1 min prior to remineralization. Group C did not receive a fluoride treatment, and group D (control) was stored in distilled water instead of bleaching. Microhardness (VHN) was evaluated before the experimerits and after the second and fourth cycle, respectively. Final hardness was calculated as percentage of the initial hardness. Analysis of variance was applied to the data followed by pairwise comparisons with corrected level of significance (P < 0.01). Hardness decreased significantly in groups A‐C compared to the control group (D). The bleached and unfluoridated specimens (group C) showed a significantly higher hardness loss compared to the fluoridated specimens, whereas no significant difference was observed between the two fluoridated groups. It is concluded that remineralization of bleached enamel is improved by application of highly concentrated fluorides.
Water sorption and solubility of resin‐modified polyalkenoate cements
Authors: YAP A. , LEE C. M.
Published: August 2010

summary
The purpose of this study was to compare the water sorption and solubility of several resin‐modified polyalkenoate cements. The materials evaluated included Variglass used as a restoration, base and liner; Fuji II LC® Fuji Liner® Vitrebond® Vitremer® and Photac‐Bond®. Z100, a composite resin, was used as control. All specimens were manipulated according to the manufacturers' instructions and then subjected to water sorption and solubility tests based on the ISO 4049 requirements. Data were subjected to one‐way anova and Duncan's test at a 0.05 significance level. Results show that the composite resin control had significantly less water sorption than any of the resin‐modified polyalkenoate cements evaluated. The degree of water sorption was product dependent and appeared to be influenced by the resin (HEMA) content. There was no apparent correlation between water sorption and solubility. Some of the resin‐modified polyalkenoate cements retained water in their set structure and hence solubility could not be assessed.
Release of cariostatic agents from a new buffering fluoride‐ and xylitol‐containing lozenge to human whole saliva in vivo
Authors: TENOVUO J. , HURME T. , AHOLA A. , SVEDBERG C. , OSTELA I. , LENANDER‐LUMIKARI M. , NEVA M.
Published: August 2010

summary
A new buffering lozenge (sucking tablet) was developed for patients susceptible to dental caries and erosion, in particular for those with reduced salivary secretion. As active ingredients this lozenge comprises of a combination of xylitol, fluoride, calcium, phosphate, zinc and buffering compounds. To test the lozenge's activity in vivo, the release of ingredients was monitored in 19 healthy subjects for 22 min after sucking the lozenge was completed. In subjects with a normal salivary secretion rate the lozenge caused only a slight stimulation of saliva flow, but a significant elevation both in salivary pH and buffer effect was observed. Furthermore, fluoride, calcium and phosphate were effectively released into whole saliva with peak values 2–4 min after use. The same salivary parameters were also quantitated after 1 month's regular use (3 lozenges/day) but no consistent long‐term changes were found. Salivary mutans streptococci and total anaerobic microflora did not change significantly during the long‐term use. The results show that the buffering fluoride‐ and xylitol‐containing lozenge, which also releases calcium and phosphate, is active in vivo but its serviceability as a remineralizing agent, in particular for elderly patients with reduced salivary flow rate, has to be analysed separately.
Oral mucosal lesions and oral hygiene habits in the home‐living elderly
Authors: NEVALAINEN M.J. , NÄRHI T.O. , AINAMO A.
Published: August 2010

summary
A large epidemiological health investigation, the Helsinki Ageing Study (HAS), was performed in 1989–1991 in Helsinki, Finland. We report here the prevalence of oral mucosal lesions in 338 76‐, 81‐ and 86‐year‐old home‐living elderly people, who completed the oral health investigation at the Institute of Dentistry, University of Helsinki. One or more lesions were found in 128 subjects (38%). Fifty‐one per cent of the edentulous complete‐denture wearers and 31% of the elderly with some natural teeth had mucosal lesions. The most common finding was inflammation under the denture, which occurred alone or combined with other lesions in 25% of the denture wearers. The three most common mucosal changes not related to denture wearing were coated changes of the tongue (7%), angular cheilitis (6%) and varicose veins under the tongue (4%). No differences were found in the number of mucosal lesions among the three age groups. Angular cheilitis and inflammation under removable dentures were more frequent in women than in men. However, no other differences were found in the presence of mucosal lesions between sexes. The total number of mucosal lesions correlated positively with the number of medications used daily. Ninety‐six per cent of the subjects with complete dentures, and 98% of those with some natural teeth reported cleaning their dentures at least once a day. Of the denture wearers, 88% reported cleaning their oral mucosa also, as part of their oral hygiene routine. The presence of mucosal lesions was related to self‐reported cleaning of the denture‐bearing mucosa. However, no association was observed between cleaning frequency and presence of mucosal changes.
Effects of surface properties on bond strength between layers of newly cured dental composites
Authors: LI J.
Published: August 2010

summary
The shear strength was measured of a polymerizing increment to a newly cured composite increment of the same material with various surface properties. The results showed that the materials with the original surface which had been cured against a cover glass resulted in a significantly higher bond strength than any of the other preparations. It was concluded that the unreacted double bonds (due to the oxygen inhibition) functioned as a bonding medium between two increments of dental composites. The process which impaired the original cured surface decreased the bonding between increments.
Changes of surface texture of enamel in vivo
Authors: WHITEHEAD S.A. , LO L.Y. , WATTS D.C. , WILSON N.H.F.
Published: August 2010

summary
There are various methods of measuring tooth wear, including that which could be considered to be associated with acid erosion. However, the present systems are limited in that they require an extended period of study to detect wear and also they do not give any insight as to the underlying mechanism of the tooth tissue loss. The aim of this study was to use a profilometric measuring system analysing novel surface texture parameters normally associated with the automobile industry to describe the wear and run‐in behaviour of machined sliding engine parts. The texture parameters selected were the traditional Ra parameter and also parameters derived from the bearing ratio. Analyses of the surface texture of the labial surface of upper central incisors at an interval of three months indicated that the enamel surface was smoother but there were subtle changes occurring to the enamel. There was a statistically significant increase in the depth of pits/pores of the enamel surface, which could be identified as sites of retention of exogenous acid or chelating agent. The effects of acid erosion are not uniform but are dependent upon several factors; the configuration of the enamel surface may play an important part in the mediation of acid erosion type lesions.
Oral awareness and ability to detect dental plaque*
Authors: WRIGHT S. M.
Published: August 2010

summary
Individuals exist who are unaware of the plaque on their teeth and unable to feel with their tongue any difference between tooth surfaces that are smooth and plaque free and those that are irregular or rougher because of a plaque coating. Oral form recognition (OFR), oral roughness discrimination (ORD) and plaque detection ability were examined in 46 undergraduate dental students. Forty‐five of the students also completed Form C of Cattell's 16 PF Questionnaire. No relationship was found between the subjects'ability to detect dental plaque and tbeir skills at either distinguishing between different surface roughnesses or recognizing forms orally. The association between personality and oral awareness Was unclear.
Comparison between the sequential and simultaneous approaches for the restoration of adjacent proximal cavities
Authors: GEIGER S.B.
Published: August 2010

summary
The clinical situation in which several proximal carious lesions have to be treated is frequently encountered. The need to provide a cost‐effective and time‐effective treatment often compels the clinician to perform multiple adjacent proximal restorations simultaneously, at the same treatment session. Alternatively, such treatments may be performed sequentially in successive sessions. The different possible treatment modalities and their clinical sequel are described. Examination of the clinical results suggests that the preferred restorative procedure is the sequential one, enabling an optimal restoration of the original anatomical form, which is important for the proper health and function of the teeth and the surrounding periodontal tissues.
Experimental wax mixtures for dental use
Authors: KOTSIOMITI E. , McCABE J.F.
Published: August 2010

summary
Improvements in the properties of dental waxes were sought by alterations in their composition. Twenty‐six blends of paraffin wax, beeswax and inorganic filler were subjected to the following tests: plastic deformation (flow), linear thermal expansion, elastic modulus and flexural strength. Flow tests were conducted in accordance with the corresponding ISO specification, Thermal expansion coefficients were estimated using thermomechanical analysis. Mechanical properties were tested using a universal testing machine. Pure paraffin and beeswax were used as controls. The results were subjected to analysis using correlation and regression. Regression coefficients in the range of 0.90–0.99 were obtained in most cases, flow tests exhibiting the highest coefficients and flexural strength the lowest. The incorporated filler particles reduced the flow of the natural waxes, especially of the ester‐containing beeswax, and improved the elastic modulus and strength. Good correlation was found between the ingredient proportions and measured properties, suggesting a relationship between them, although this is quite complicated in the case of tertiary wax mixtures. The experimental blends exhibited properties that are potentially useful for a range of clinical applications.
Condylar asymmetry and handedness in patients with temporomandibular disorders
Authors: MILLER V. J.
Published: August 2010

summary
The relationship between condylar asymmetry and handedness of dentate patients with temporomandibular disorders was investigated. A group of 28 patients (22 females and 6 males) was studied. The mean age was 28.29 years, with a range from 10 to 54 years. The association between handedness and the sign of the condylar asymmetry index was examined using Fisher's exact test. No difference was found between sign and handedness (P>0.05). This suggests that handedness does not affect the asymmetry index in this group of patients.
Comparative wear ranking of dental restorative materials utilizing different wear simulation modes
Authors: YAP A.U.J. , TEOH S.H. , HASTINGS G.W. , LU C.S.
Published: August 2010

summaryThe aim of this study was to compare the wear of seven different restorative materials using two different wear simulation modes. This included a non‐impact sliding wear test (rotary pin and disc) and an impact‐cum‐sliding wear test (masticatory simulator). The difference in wear ranking between the two wear tests was compared as well as the correlation of wear to the hardness of the materials. Hardness ranking in the order of decreasing hardness was as follows: Dispersalloy®(DA), P50®(P50), Hi‐Dense(r)(HD), TPH®(TPH), Fuji II LC®(FJ), Dyract®(DR) and Vitremer®(VM). For volumetric wear using the non‐impact sliding test, the following ranking in the order of decreasing wear resistance was obtained: DA, TPH, DR, HD, VM, FJ, P50. The results for volumetric wear with impact‐cum‐sliding wear testing in the order of decreasing wear resistance were: TPH, DR, P50, AR, FJ, VM, HD. Results showed that there is no correlation between hardness and wear resistance. There is also no correlation between impact‐cum‐sliding wear and non‐impact sliding wear. Impact wear should be considered in future two‐body wear assessment of materials.
Reported symptoms and clinical findings in a group of subjects with longstanding bruxing behaviour
Authors: KAMPE T. , TAGDAE T. , BADER G. , EDMAN G. , KARLSSON S.
Published: August 2010

summary
Signs and symptoms of craniomandibular dysfunction (CMD) and social medical history were reported in 29 subjects, aged 23–68 years, with longstanding (5 years or more) bruxing behaviour. The subjects were selected from answers to an advertisement in the local newspaper. The subjects presented many symptoms of a general character including somatic and psycho‐social problems, sleep disorders (72%), and pain (86%). More than half of the subjects (55%) had symptoms every day. Frequent aches in the neck, back, throat or shoulders were reported by 69% and frequent headache by 48% of the subjects. The most common symptoms of CMD were pain in the face or jaws (48%), stiffness in the jaws in the morning (44%), temporo‐mandibular joint (TMJ) sounds (34%) and fatigue in the jaws during chewing (38%) and the most common clinical signs were more than three muscles tender on palpation (76%), TMJ‐sounds (55%) and tenderness of TMJ on lateral palpation (66%). There was a statistically significant correlation between frequent tooth clenching and headache, pain in the neck, back, throat or shoulders, sleep disorders and high scores of the clinical dysfunction index (Di). The frequent clenchers had higher score values than the ‘non‐clenchers’ for pain in the face and the jaws; headache; pain in the neck, back, throat or shoulders and the clinical dysfunction index (Di). These findings indicate a causal relationship between frequent tooth clenching and signs and symptoms of CMD. including headache and pain in the neck, back, throat or shoulders and high pathogenicity for frequent clenching. However, the material in this study is small and some precaution must be taken prior to generalized conclusions. More studies are required, especially sleep laboratory investigations, which could perhaps give answers to some of the numerous questions in this unexplored field of odontology.
Sex difference of electromyogram of masticatory muscles and mandibular movement during chewing of food
Authors: NAGASAWA T. , YANBIN XU , TSUGA K. , ABE Y.
Published: August 2010

summary
The aim of this study was to investigate whether there were sex differences in the electro‐myograms (EMG) of the masticatory muscles and in the mandibular movement of young adults when chewing food. Twenty subjects with normal dentitions were selected. The II test foods selected were all easily available in Japan. The results showed firstly that although there were no significant differences of chewing frequency between males and females, females chew food more slowly with less masticatory force and narrower mouth opening width than males; and secondly it appears that the chewing function in females is lower than in males.
Study of jaw movement and masticatory muscle activity during unilateral chewing with and without balancing side molar contacts
Authors: NISHIGAWA K. , NAKANO M. , BANDO E.
Published: August 2010

summary
This research evaluated the relationship between balancing side molar contacts and chewing patterns measured with a jaw movement analyser and multi‐channel electromyography (EMG) of the masticatory muscles. Nine healthy subjects with relatively normal occlusions participated in the experiment and were divided into those with balancing side molar contacts and those without. The block gum chewing task was performed on each side of the mouth for 10 s. The results showed more asymmetrical levels of jaw closing muscle activity during unilateral chewing in the group with balancing side molar contacts when compared with the group without these contacts.
Amitriptyline treatment of chronic pain in patients with temporomandibular disorders
Authors: Plesh O. , Curtis D. , Levine J. , Mccall Jr W. D.
Published: August 2010

Randomized clinical trials of amitriptyline will require data from pilot studies to be used for sample size estimates, but such data are lacking. This study investigated the 6‐week and 1‐year effectiveness of low dose amitriptyline (10–30 mg) for the treatment of patients with chronic temporomandibular disorder (TMD) pain. Based on clinical examination, patients were divided into two groups: myofascial and mixed (myofascial and temporomandibular joint disorders). Baseline pain was assessed by a Visual Analogue Scale (VAS) for pain intensity and by the McGill Pain Questionnaire (MPQ). Depression was assessed by the Beck Depression Inventory (BDI) short form. Patient assessment of global treatment effectiveness was obtained after 6 weeks and 1 year of treatment by using a five‐point ordinal scale: (1) worse, (2) unchanged, (3) minimally improved, (4) moderately improved, (5) markedly improved. The results showed a significant reduction for all pain scores after 6 weeks and 1 year post‐treatment. The depression scores changed in depressed but not in non‐depressed patients. Global treatment effectiveness showed significant improvement 6 weeks and 1 year post‐treatment. However, pain and global treatment effectiveness were less improved at 1 year than at 6 weeks.
Relationship between oral function and occlusal support in denture wearers
Authors: Yamashita S. , Sakai S. , Hatch J. P. , Rugh J. D.
Published: August 2010

Patients with removable partial dentures or complete dentures do not demonstrate masticatory function to the same level as patients with a full set of natural teeth. The purpose of this study was to characterize the relationship between reduction of masticatory function, in terms of masticatory performance and bite force, and the existence of remaining natural occlusal supports as assessed by the Eichner index. One hundred and eighteen removable partial denture and complete denture wearers were selected for analyses. These subjects were divided into four groups depending upon the number of occlusal supports. Seventy dentate subjects with full occlusal support were designated as a comparison group. Bilateral bite force was measured at the first molar region in all subjects. Masticatory performance was assessed using the modified Masticatory Performance Index. Peanuts were used as the test food. Both bite force and masticatory performance were significantly associated with group classification. Moreover, both bite force and masticatory performance of the four denture groups were significantly reduced compared to the comparison group and this tendency was remarkable for the denture groups without occlusal support. These results suggest that the existence of functional tooth units may be a key factor in preservation of masticatory function.
Dynamic viscoelastic properties of photo‐activated composite resins containing short glass fibres
Authors: Kanayama H. , Kanie T. , Inoue K.
Published: August 2010

The dynamic shear modulus in torsion (G′), water absorption, thermal expansion and residual monomer of the reinforced materials produced by adding four short glass fibres (19 μm in mean diameter and 86·1–763 μm in mean length) and one spherical E glass (11·1 μm in mean diameter) were examined and discussed in comparison with those of the materials without filler. G′ of short fibre reinforced composites increased with fibre length and reached a maximum value near 382 μm for a dry specimen and near 156 μm for a wet one. In addition, the coefficient of thermal expansion of the fibre reinforced composites and the amount of residual monomer decreased considerably compared with those of composites containing spherical glass. There was no significant difference in water absorption between the fibre reinforced composites and the composites containing spherical glass. Therefore, it was concluded that the reinforcement method of adding short glass fibres is favourable for improving the viscoelastic properties of the materials.
Effect of temperature and flux concentration on soldering of base metal
Authors: Lee S.‐Y. , Lin C.‐T. , Wang M.‐H. , Tseng H. , Huang H.‐M. , Dong D.‐R. , Pan L.‐C. , Shih Y.‐H.
Published: August 2010

The present study used the acoustic emission (AE) technique to evaluate interactions among soldering temperature, flux treatment, and the resultant ultimate tensile strength (UTS). Scanning electron microscopy (SEM) was used to examine fracture surfaces of the solder joints. Specimens were cast from removable partial denture alloy and then placed in a jig with a gap distance of 1·0 mm. A high‐frequency soldering machine with an optical pyrometer was used for soldering at 1150°C and 1200°C, respectively. The flux concentrations were 67% and 75%. The soldered specimens were subjected to tensile test at a crosshead speed of 0·05 mm/min. During testing, acoustic emissions in the frequency range of 100–1200 kHz were collected, filtered, recorded, and processed by a sensing device. The results were analysed by anova and Tukey LSD test. UTS at different temperatures showed no significant difference according to either mechanical or acoustic results. But in the 1200°C group, the UTSs and AE counts showed significant differences (P<0·05) at both flux concentrations. SEM showed that the 1200C group had better dendritic crystal structure than did the 1150°C group. In the 1200°C group specimens with 67% flux had fewer flux inclusion bodies and dendritic crystals than did specimens with 75% flux. The 75% flux subgroup produced high‐amplitude (60–70 dB) acoustic signals within the elastic deformation zone, while the 67% flux subgroup produced similar signals within the plastic deformation zone, either beyond the 0·2% yield point or before fracture.
Adhesive bonding of stainless steels and their component metals
Authors: Matsumura H. , Tanoue N. , Atsuta M.
Published: August 2010

The purpose of the current study was to evaluate the bond strength of a metal adhesive system bonded to stainless steels and their component metals. Two sizes of disk specimens (10 and 8 mm in diameter×2·5 mm thickness) were machined from two stainless steels designed for magnetic attachment (AUM20 and SUS 316L), as well as from high‐purity chromium (Cr) and nickel (Ni) metals for reference. The specimens were air‐abraded with alumina, either primed with a metal conditioner (Cesead II Opaque Primer) or left unprimed, and bonded with an adhesive resin (Super‐Bond Opaque). Shear bond strengths were determined before and after thermocycling, and the results were analysed by analysis of variance (anova). Post‐thermocycling bond strengths of the unprimed groups were 16·3 MPa for the AUM20 alloy, 7·5 MPa for the SUS 316L alloy, 31·1 MPa for Cr and 3·1 MPa for Ni. Those of the conditioned groups were 30·3 MPa for the AUM20 alloy, 32·9 MPa for the SUS 316L alloy, 39·3 MPa for Cr and 13·1 MPa for Ni. Application of the conditioner elevated the bond strengths of all groups (P<0·05). It can be concluded that combined use of the conditioner and the Super‐Bond adhesive is effective for bonding the stainless steels examined, and that Cr is a suitable component for the bonding system in question.
Influence of protrusive tooth contact on tapping point distribution
Authors: Ueno T. , Baba K. , Fueki K. , Ai M. , Ohyama T.
Published: August 2010

This study investigated the influence of protrusive tooth contacts (tooth contacts during mandibular protrusion) on the tapping point distribution. Nine healthy subjects volunteered for this study and the protrusive tooth contact pattern, as well as the retrusive tooth contact pattern, was altered on four maxillary occlusal splints. The first splint was adjusted to make the sagittal incisal path of protrusion and retrusion equivalent to that of the natural dentition. The second and third splints had partial and complete elimination of the protrusive tooth contact, respectively. The fourth splint had complete elimination of both protrusive and retrusive tooth contacts. The subjects were asked to use each splint continuously for 1 week. The tapping point distribution was measured on the 7th day after insertion of each splint. The four experimental occlusal conditions were found to have a significant effect on the tapping point distribution. The complete elimination of the protrusive tooth contact caused an anterior tapping point location and an increase in the tapping point area. The former tendency was found to be independent of the presence of the retrusive tooth contact. In conclusion, it was suggested that the protrusive tooth contact plays a significant role in maintaining the consistency and stability of the tapping point.
Direct tensile strength of visible light‐cured restorative materials containing fluoride
Authors: Hotta M. , Kawano S. , Sekine I.
Published: August 2010

The purpose of this study was to compare the fluoride release and direct tensile strength at 24 h, 1 month, and 3 months of two conventional glass–ionomers, two visible light‐cured resin‐modified glass–ionomers, a polyacid resin composite and two resin composites. The results were statistically analysed using ANOVA and Fisher’s PLSD at α=0·05. The data on fluoride release indicated that the immersion period (24 h, 1 month, and 3 months) significantly influenced the cumulative amount of fluoride released (P < 0·001). The direct tensile strengths after 1 month of storage were significantly higher than those after 24 h or 3 months of storage (P < 0·001). Thus, the cements and resins were not weakened by the loss of fluoride. Conventional glass–ionomer cement showed the lowest direct tensile strength. Resin‐modified glass–ionomer behaved in between the resin composites and conventional glass–ionomers in terms of all three testing times, however, the polyacid resin composites most closely resembled the resin composites. The polyacid resin composites had greatly enhanced direct tensile strength, however, this material also reduced the fluoride availability.