bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new experimental restoration model in man for studying enamel reactions
Authors: GANGLER P. , HOYER I. 
Published: June 2007

SummaryA new model of experimental restoration is suggested for testing the marginal imperfections of composite resin, for examining the surface morphology of composite restorations and of sound, etched and remineralized enamel. Enamel‐ dentine samples with standardized cavities and composite restorations were placed on lower removable partial dentures using the etching technique. After 12 and 28 days the specimens were examined in a scanning electron microscope (SEM), operated at 15 kV.After 12 days the examination of the conventional composite resin by SEM showed extremely rough structures. The use of the enamel etch techniques produces acceptable marginal conditions with tags and some minor gaps. Etching the enamel emphasizes its prismatic structure and reveals the typical pattern of demineralization, involving prism cores and the preferential dissolution of prism peripheries.After 12 days the SEM appearance of uncovered etched enamel suggested that incomplete remineralization had occurred. After 28 days the mineral recoating, which had progressed further, predominantly involved prism‐orientated repair. The experimental model described here is more accurate, highly standardizable and easily accessible, compared with conventional clinical and replica techniques.
Tooth loss and remaining occlusion in a Dutch population
Authors: BATTISTUZZI P. , KÁYSER A. , PEER P. 
Published: June 2007

SummaryThe aim of this study was to gain a better insight into the tooth‐loss pattern in terms of frequency, location and impaired occlusion. The sample, stratified according to socio‐economic class and age, condisted of 750 subjects. The investigation was done by questionnaire and clinical examination. The non‐response was small (15%). With increasing age, more teeth were missing. In the lower socio‐economic group more teeth were missing than in the higher socio‐economic group. The percentage of totally edentulous persons as well as the percentage of persons with one edentulous jas increased with age. Also, the percentage of antagonistic tooth contacts: first premolar, second premolar, second molar and first molar. In all strata the percentage of antagonistic contacts in the premolar area was larger than in the molar area.
Rehabilitation with removable dentures among the dentate population in Finland
Authors: RANTA K. 
Published: June 2007

SummaryThe information available on the rehabilitation with removable dentures among dentate subjects is contradictory. In the present study, the most common type of rehabilitation was a complete maxillary denture with or without a partial one. Nineteen per cent of men and 27% of women belonged to this category. Partial denture(s) without a complete one were worn by 11% of men and 15% of women.The odds ratio of having partial denture(s) was significantly higher among women, among people with a medium level of income, with a regular dental attendance pattern, and with a shorter distance to the nearest dental clinic. The presence of a complete denture significantly decreased the odds ratio of having a partial denture. The effect of age was non‐significant in the two youngest age categories.The odds ratio of having a single complete denture was significantly higher among women, among people with a medium level of income and with a shorter distance to the nearest dental clinic. The presence of a partial denture and belonging to the oldest age bracket decreased the odds ratio significantly. Regularity of use of dental services had a non‐significant effect.
Types of patients with crowns in general dental practices
Authors: LEEMPOEL P. J. B. , van ROSSUM G. M. J. M. , de HAAN A. F. J. , REINTJES A. G. M. 
Published: June 2007

SummaryBased on data from patient records of 9996 crowns constructed in forty general practices, it is discussed what crown types have been constructed in different patient categories. It was found that female ‘crown patients’ received on average more crowns than male patients. Hardly any difference was found between the average number of crowns the patients with or without reimbursement had received. In the younger patients (< 21 years) more jacket crowns were constructed. The 21–30 year group received more full metal crowns, whereas the oldest group (> 51 years) had more metal‐porcelain crowns.Sick‐fund patients received more jacket crowns and metal‐porcelain crowns on front teeth, while private patients received more full‐metal crowns.
A method for standardization of silent period measurements in human masseter muscle
Authors: TÜRKER K. S. 
Published: June 2007

SummaryThe effect of bite force and stimulus intensity on the electrically induced SP has been studied. The results from the present study and earlier investigations suggest that the following guidelines should be used in future SP studies.

The electrical rather than mechanical way of stimulation should be preferred since the stimulus parameters and the receptors stimulated can easily be determined.
The sensory perception threshold (T) of subjects should be used when studying and comparing the SP between individuals rather than the actual values of the electrical stimulation since the value of the sensory perception threshold varies from subject to subject.
Rectified and averaged EMG records should be used rather than single raw traces since it is not possible to measure the duration of SPs from single traces.
The subject should be asked to perform 25% of his/her MBF and the BF should be given as a feedback.
A stimulus intensity of about 6T should be used so that small changes in the BF would not affect the SPD.
A jaw separation of about 10 mm should be selected in the subjects with normal overjet (2–3 mm), this being slightly thicker than the average isometric force transducer. The transducer can be brought to this thickness using acrylic resin.
A head rest should be used to keep the head position constant (and hence constant jaw position with respect to the transducer) since the head position alone may change the reflexes elicited in the jaws region.
The recognition of craniomandibular disorders—a comparison between clinical and radiographic findings in eighty‐nine subjects
Authors: BEZUUR J. N. , HABETS L. L. M. H. , LOPEZ V. JIMENEZ , NAEIJE M. , HANSSON T. L. 
Published: June 2007

SummaryA comparison has been made between clinical and radiographical findings in a study of eighty‐nine patients suffering from craniomandibular disorders. In general it was found that condylar changes were more common in these patients than in earlier studies concerning the severe problems of craniomandibular disorders. A statistically significant correlation between clinical and radiographical findings was found for crepitation with osteophyte formation of the condyle (P<0.01). After clinical separation of the patients into two groups based upon the origin of pain, myogenous versus arthrogenous, no radiographical correlation could be made except for condylar osteophytes. With the clinical method used for separation of patients it was found that the clicking of the temporomandibular joint (TMJ) was more common among myogenous patients (P<0.05); crepitation was more common among arthrogenous patients (P<0.01), as was limited mouth opening (P<0.05) and deviation on opening (P<0.05). Radiographically, the only statistical difference between the two groups was found for osteophyte formation of the condyle, this was more common among arthrogenous patients (P<0.05). As the clinical method has been tested earlier, the results of this study lends support to the idea that conventional radiographical examination is of limited use in the initial diagnostics of craniomandibular disorders. Therefore new alternatives have to be developed.
Medical science and the patient
Authors: RIPPIN J. W. 
Published: June 2007

SummaryClassification is necessary to most forms of thought, and the scientific method requires particular refinement of this process in order to formulate its laws. But there is nothing fundamental about any classification; its categories are chosen for a particular purpose only, and often at least some of the subjects do not fall readily into any class. Furthermore, since only few of an individual's characteristics are used as classifying attributes, individuals themselves become submerged in the classes, and their individuality lost in the scientific laws that arise therefrom. Desiderata of science and uniqueness are therefore opposed—and they are irreconcilable because absolute knowledge is either non‐existent or unattainable. Thus, the decision as to whether an individual patient is healthy or diseased must be made on the basis of diagnostic laws which, as far as the individual is concerned, are inaccurate and may turn out to be spurious or even meaningless. These laws are therefore only guide‐lines which must be ‘re‐individuated’ in clinical practice. In essence, the individual's health depends on the individual's biology.
The effect of retention grooves on gingival marginal leakage in class II posterior composite resin restorations
Authors: BEN‐AMAR A. , LIBERMAN R. , NORDENBERG D. , METZGER Z. 
Published: June 2007

SummaryIn this laboratory study, the effect of retention grooves in the proximal portion of class II cavities on the marginal microleakage using light‐cured composite resin was examined. The retention grooves were placed at the axio‐facial and axio‐lingual line angles and in the gingival floor of the cavities.The teeth were restored with Herculite composite resin with etching and dentine bonding and polymerized in two different ways: (i) a single mass of restorative material was polymerized all at once; and (ii) incrementally placed amounts of restorative material were each polymerized separately until the cavity was completely filled.Marginal microleakage was evaluated by the degree of dye penetration at the gingival margin of the restorations after suitable thermocycling procedures.It was concluded that marginal microleakage was significantly reduced when the composite resin was placed and polymerized incrementally, and that no advantage was gained from retention grooves with this incremental technique. However, when polymerizing in one single mass of material, retention grooves were found to be necessary in order to reduce marginal microleakage at the gingival wall.
The effect of seating pressure and powder/liquid ratio of zinc phosphate cement on the retention of crowns
Authors: KARIPIDIS A. , PEARSON G. J. 
Published: June 2007

SummaryThe effect of three different powder/liquid ratios of one zinc phosphate cement on the early retention of a standard crown on metal and tooth dies was investigated. Two different seating pressures were evaluated. The results indicate that the effect of variation in the powder/liquid was not significant. The part played by the seating force was significant, the higher seating force resulting in a greater force being required for displacement after 1h. Greater forces of removal were required when tooth dies were used.
A criterion for the selection of artificial posterior teeth
Authors: YOSHIDA K. , OKANE H. , NAGASAWA T. , TSURU H. 
Published: June 2007

SummaryMandibular movement and masticatory performance were evaluated in the edentulous patients with an experimental denture using posterior artificial teeth of different occlusal schemes in order to determine the criterion for the selection of posterior artificial teeth.Lower masticatory performance was observed with non‐anatomic posterior teeth than with semi‐anatomic or anatomic ones regardless of the condition of residual ridge and inclination of the horizontal condylar guidance. The value of the lateral component of the masticatory cycle was closely related to the inclination of the cusp and the value of masticatory performance. This suggested strongly that the component could be a criteria for the selection of the type of the artificial posterior teeth.
The Orthopantomogram®, an aid in diagnosis of temporomandibular joint problems.
Authors: HABETS L. L. M. H. , BEZUUR J. N. , NAEIJI M. , HANSSON T. L. 
Published: June 2007

SummaryVertical measurements of the Orthopantomogram® of 152 patients were made for condylar and rami heights. The symmetry between the right (R) and the left (L) side was calculated with the formula: |(R−L)/(R+L)|. A statistically significant difference between the patients of a routine dental group and the patients treated for craniomandibular disorders was found regarding condylar height symmetry.
The recognition of craniomandibular disorders—a comparison between clinical, tomographical, and dental panoramic radiographical findings in thirty‐one subjects
Authors: BEZUUR J. N. , HABETS L. L. M. H. , HANSSON T. L. 
Published: June 2007

SummaryA comparison between clinical, tomographical, and dental panoramic radiographical findings was made in thirty‐one female patients suffering from craniomandibular disorders (CMD). In general it was found that condylar sclerosis was more common in these patients than in earlier studies. After clinical separation of the material into two groups based upon the origin of pain, myogenous versus arthrogenous, no radiographical confirmation of the differential diagnostics could be made. Regarding vertical condylar asymmetry measured on the Orthopantomogram®, it was found that 74% of the patients with CMD had more than the 3% of asymmetry regarded as within normal limits. It seems that with an increasing severity of the disorder the level of condylar asymmetry appears less. If the interpretation of the findings is correct its conclusion might lead to the recognition of a morphological factor which could contribute to the development of a craniomandibular disorder.
Stress in patients with pain in the muscles of mastication and the temporomandibular joints
Authors: LUNDEEN T. F. , GEORGE J. M. , STURDEVANT J. R. 
Published: June 2007

SummaryThis study examined the role of stress in subjects having combined muscle and temporomandibular joint pain compared to subjects having only muscle pain or only joint pain. It was found that the combined pain (n=39) and muscle pain (n=24) groups had comparable levels of pain intensity and activity impairment. The combined pain group, however, had the lowest level of stress and was rated lower than the muscle group in clinicians ratings of psychological factors, stress and chronicity. The combined pain group and joint pain group (n=28) were found to be comparable in terms of the clinician's ratings. This data does not support the concept of a progression of symptoms from muscle pain to combined muscle and joint pain that would be expected from a stress‐induced muscle hyperactivity model of temporomandibular disorders.
Effect of exposure time on the depth of polymerization of a visible light‐cured composite resin
Authors: BAHARAV H. , ABRAHAM D. , CARDASH H. S. , HELFT M. 
Published: June 2007

SummaryThe effect of exposure time of a visible light source on the depth of polymerization and degree of hardness of a sample of Occlusin posterior composite resin was investigated. The border between cured and non‐cured composite resin was identified by a change in colour and by applying pressure with a scalpel. Knoop hardness tests were performed perpendicular to the long axis of illumination.The composite resin nearer to the light source underwent more complete polymerization. Increased exposure time resulted in greater depth of cure. The rate of polymerization was greatest in the first 10 s. Maximum hardness measured up to a depth of 1 mm obtained after 80 s of exposure time. At greater depth, a decrease in Knoop hardness was observed. At exposures under 80 s, maximum hardness was not achieved even at a depth of only 1 mm.
The determination of elastic recovery of impression materials at the setting time
Authors: JAMANI K. D. , HARRINGTON E. , WILSON H. J. 
Published: June 2007

SummaryOne of the prime requisites of an elastomeric impression material is that it should possess adequate elastic recovery on removal from undercut areas. Most standard methods of measuring elastic recovery rely on the preparation of specimens in moulds. The specimens are subsequently removed and subjected to compressive or tensile stresses several minutes after the setting time.The equipment described in this paper has been developed to enable elastic recovery values to be determined at times in the vicinity of the setting time. A shear strain is induced in the material for a short time and the resulting recovery recorded graphically. Results indicate that there is a significant improvement in elastic recovery from just prior to until just after the setting time.
Rigidity of elastomeric impression materials
Authors: JAMANI K. D. , HARRINGTON E. , WILSON H. J. 
Published: June 2007

SummaryThe rigidity of an impression material should be less than a certain value in order that excessive forces are not required when taking impressions of undercut areas. Conversely, the impression should be sufficiently rigid to withstand the weight of stone whilst pouring the cast without distortion.This paper describes a method of determining elastic modulus values at times as early as the setting time of the material. Results indicate that the elastic modulus values increase from the setting time to 30 min after the start of mix. Values are presented for a representative range of elastomeric impression materials.
The recognition of craniomandibular disorders; condylar symmetry in relation to myogenous and arthrogenous origin of pain
Authors: BEZUUR J. N. , HABETS L. L. M. H. , HANSSON T. L. 
Published: June 2007

SummarySixty‐seven per cent of the forty‐three patients suffering from craniomandibular disorders (CMD) had a vertical condylar asymmetry greater than 3%. After division into two different groups, myogenous and arthrogenous origin of pain, it was found that myogenous patients were younger and showed significantly bigger asymmetry between the vertical heights of the left and right condyles, evaluated on an Orthopantomogram®, than the patients with arthrogenous origin of pain (P<0.05). The mean vertical condylar asymmetry was 9.10% and 4.83%, respectively. It is suggested that the possible triggering morphological condylar asymmetry on the pathogenesis of a CMD should be recognized at an early stage of the disorders development. The use of a screening protocol and an Orthopantomogram® could be of preventive importance in daily practice.
Clinical performance of resin‐bonded bridges: a 5‐year prospective study. I. Design of the study and influence of experimental variables
Authors: CREUGERS N. H. J. , SNOEK P. A. , VAN'T HOF M. A. , KÄYSER A.F. 
Published: June 2007

SummaryA total of 203 resin‐bonded bridges were inserted under controlled clinical conditions and evaluated over a period of 5 years. The study included two experiments to test the influences of retainer type, cementation material and operator on the success rate of resin‐bonded bridges. The overall survival at 5 years was 75%. Micromechanical retainers were better than macromechanical retainers. For inserting micromechanical retainers, the cementation materials Clearfil F and Panavia Ex were better than Conclude. An operator effect was not found in this study.
Solubility of zinc oxide‐eugenol and calcium hydroxide cements in simulated dentinal fluid
Authors: DRISCOLL C. F. , WOOLSEY G. D. , REDDY T. G. , CRAIG R. G. 
Published: June 2007

SummaryThe solubility of four dental cement bases was measured in simulated dentinal fluid and distilled water to evaluate the relevancy of the American Dental Association solubility test for cement bases in contact with vital dentine. A simulated dentinal fluid was formulated utilizing glucose, distilled water, and sterile human plasma. Cement‐base samples were immersed in either distilled water or simulated dentinal fluid at 37°C in a shaker water‐bath for 1, 2, or 3 months. Weight loss values were compared utilizing a three‐way analysis of variance. Zinc oxide‐eugenol cements were significantly more soluble in simulated dentinal fluid than distilled water, while the calcium hydroxide cement bases were significantly more soluble in distilled water than simulated dentinal fluid.
Effect of chewing training on mandibular postural position
Authors: TZAKIS M. , CARLSSON G. E. , KILIARIDIS S. 
Published: June 2007

SummaryThe inter‐occlusal rest space (free‐way space) was studied before and after short and long periods of chewing of a hard resin in 15 healthy subjects. During a month of daily training for one hour of chewing no significant changes in the interocclusal rest space were seen. After 30 min of intense chewing the mean interocclusal distance increased to about twice its original size. This occurred both before and after the training period. In a control group of eight subjects without any chewing exercise no significant changes in the interocclusal rest space were noticed during the observation period.
Relative influence of plaque control, scaling and root planing on occlusal sounds
Authors: MURAMOTO T. , TAGUCHI S. , ASAZUMA Y. , KIFUNE R. , HONMA S. , TSUCHIDA K. , HARA K. 
Published: June 2007

SummaryNine periodontally affected subjects and eight healthy subjects were selected in order to examine the effect of initial periodontal treatment on occlusal sounds. Gingival Index, probing depth, tooth mobility and occlusal sound duration via an occlusal sound analyser were recorded at the baseline. The nine periodontal patients were then treated by plaque control, root planing with general scaling and were re‐examined at 1 month and 3 months post‐operatively.The following results were obtained:(i) The normal duration of an occlusal sound is less than 10 ms.(ii) Occlusal sounds of periodontal patients were of longer duration compared with the values in healthy subjects, but decreased and approached the normal value after treatment.
Comparison of the dimensional stability of two waxes and two acrylic resin processing techniques in the production of complete dentures
Authors: SYKORA O. , SUTOW E. J. 
Published: June 2007

SummaryTwo base plate waxes and two denture processing techniques were independently compared for dimensional stability. Occlusion rims were constructed from extra hard and medium soft base plate waxes and teeth were set. Acrylic resin bases were processed by a trial packing technique, and a continuous injection system. Tooth movement was measured in the horizontal and vertical planes to assess wax and denture base dimensional changes at various steps in the process, and after 1, 3, and 8 weeks of denture base immersion in water at room temperature. Posterior palatal border adaptation, incisal pin opening and loss of centric occlusion contacts, were also measured. Results showed there were no significant differences between the two waxes as determined by tooth movement in the horizontal and vertical planes. In comparison to the trial packing technique, the continuous injection system showed significantly smaller changes for incisal pin opening and loss of centric occlusion, and better adaptation of the posterior palatal border to the cast. Measurement of tooth movement in the horizontal and vertical planes showed no significant differences between the two processing techniques for times prior to immersion in water, whereas after 8 weeks immersion the continuous injection technique showed smaller dimensional changes, relative to the original dimensions at the time of investing.