bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prosthodontic failures in patients with systemic disorders
Authors: LANGER A. 
Published: June 2007

SummaryWhen a patient wishes to be treated for dentures, a careful examination and anamnesis have to be made. In the course of the anamnesis a detailed medical and dental history has to be taken, to diagnose any systemic disease the patient might suffer from, such as metabolic, hormonal, autoimmune, neurological, mental or emotional disorders. It is necessary to assess their possible effects and relationship to complaints about previous dentures. The dentures may of course be the main offending factor or contribute to the patient's oral problems, but only when this is confirmed beyond doubt should the dentures be replaced without referring the patient for supportive treatment. In cases of transition from natural or partly natural dentition to complete dentures, these disorders must be given careful attention, since in this critical situation any present systemic instability may trigger clinical symptoms that thus far were sub‐clinical and unfelt by the patient.No improvement in patients ability to use his dentures properly can be expected unless the primary causative systemic factors have been relieved by specific therapy.It is noteworthy that the majority of problem cases are women in the postmenopausal period, because of their special susceptibility to disturbances of the systemic homeostatic equilibrium.
Treatment planning for the management of selected dento‐facial abnormalities
Authors: MURRAY C. G. 
Published: June 2007

SummaryExisting treatment planning aids for the management of dento‐facial abnormalities do not adequately assess the neuromuscular status of the oro‐facial soft tissues. Where an element of mandibular overclosure exists the patient assessment technique provides a reproducible and clinically acceptable occlusal vertical dimension of occlusion. In the three cases treated a functional impression technique for establishing the upper lip support produced a reproducible profile which was both aesthetically and functionally satisfactory.
Biological testing of dental restorative materials in vitro—a review
Authors: BROWNE R. M. , TYAS MARTIN J. 
Published: June 2007

Summary In vitro methods for the biological evaluation of dental restorative materials are discussed, with particular reference to the type of cells used, the physical state of the test material, the method of establishing cell‐material contact, and the criteria of cytotoxicity. It is postulated that in vitro methods should provide a reliable assessment of the toxicity of dental restorative materials, but since the current in vitro methods do not mimic in vivo conditions sufficiently closely, the correlation between in vitro and in vivo results is at present poor. The development of in vitro methods more closely simulating in vivo circumstances is advocated.
Limits of perceptibility of condyle displacements on temporomandibular joint radiographs
Authors: KUNDERT MARTIN 
Published: June 2007

SummaryThe present study investigated to what extent condyle positions have to be different from each other in order to be clearly detectable under clinical conditions on serial radiographs of the temporomandibular joints in identical projection. For that purpose of ten test subjects serial radiographs in optimal lateral oblique and identical projection were made with various positions of the joint. The joint was brought to these positions by displacement of the mandible to an exactly known extent with a special device. Evaluation showed that mean differences between condyle positions of 0.61 ± 0.16 mm can be recognized clearly. It was statistically proved that this value did not depend upon the experience of an examiner in reading radiographs but upon the technical quality and the interpretability of the radiographs as well as upon the radiographic dimension of the posterior joint space.
The effect of time on the marginal fracture behaviour of amalgam
Authors: MAHLER DAVID B. , MARANTZ RICHARD L. 
Published: June 2007

SummaryIn this study the effect of time on the marginal fracture behaviour of amalgam was determined. Six alloys in clinical service for up to 6 years were used as a data base and occlusal photographs were categorized according to a standard set of photographs depicting varying degrees of marginal fracture. The standard set of photographs was assigned a linear numerical scale, and the index of extent of fracture was considered to be an arithmetic mean based on this linear scale. An observed patient effect and unequal sample sizes were considered in the determination of both the mean and variance. The results of applying these procedures to the data of this study showed that marginal fracture increased with time for all alloys; that the relative ranking of alloys did not change with time; and that, with certain limitations, early time evaluations can predict long‐term behaviour.
The prosthodontic rehabilitation of selected adults class III malocclusions
Authors: MURRAY C. G. 
Published: June 2007

SummaryIn a previous paper (Murray, 1978) some of the problems associated with currently employed preoperative assessment aids were discussed. Techniques were described for establishing the occlusal vertical dimension of occlusion, and support for the upper lip. The incorporation of these treatment planning aids in the prosthodontic rehabilitation of two adult cases, with class III malocclusions, is reported.
Change in the gonial angle
Authors: FISH S. FRANCIS 
Published: June 2007

SummaryCross‐sectional studies have promoted the view that the gonial angle is increased by age and by the edentulous state. Longitudinal studies do not support this view. It is proposed that the data support the concept that the gonial angle may show enlargement or reduction, as may be expected of any bony angular relationship, and that ageing and loss of teeth are not, and should not be expected to be, the sole determinants of such change.
Crevicular temperature rises stimulated by plaque formation
Authors: MAEDA T. , EL GHAMRAWY E. , KROONE H. , RUNOV J. , STOLTZE K. , BRILL N. , Tryde G. 
Published: June 2007

SummaryIn nineteen subjects, temperatures were recorded thermo‐electrically in the vestibular and proximal crevices of fifty‐nine teeth. It was found that the formation of a new plaque was followed by a rise in crevicular temperature. In addition, it was found that the normal as well as the abnormal crevicular temperatures were higher in the mandible than in the maxillae.
Oral recognition of forms and oral muscular coordination ability. A longitudinal study in young adults
Authors: LANDT HORST , FRANSSON BO , ALIN LARS 
Published: June 2007

SummaryA study has been carried out to investigate the constancy of results in oral recognition of forms (RF‐test) and in tests which demand a fine coordination of the oral muscular apparatus (MA‐test). Twenty examinees with a mean age of 22–5 years were tested with both test forms in 1972 and retested 4 years later in 1976. The performances in the RF as well as in the MA‐test improved considerably.As to the learning (training) effect in both test forms, the test results acquired by training during the previous period have largely been preserved until the next test period 4 years later.Individuals with a given capacity to perform either the RF‐ or MA‐test, showed about the same grade of ability 4 years later. The RF‐ as well as the MA‐test seem to reflect a given ability, which, at least in this age‐group, remained constant during a period of 4 years.These results may be explained by reference to the notion of schema in which some motor‐sensory feed‐back will be stored. The specificity of the perceptual and motor patterns used, may have produced schemata with good resistance against forgetting.
Evaluation of alternative alloys to precious ceramic alloys
Authors: MEYER J.‐M. , PAYAN J. , NALLY J.‐N. 
Published: June 2007

SummaryIn the first part of this study, the microstructures and the mechanical properties of precious, semi‐precious, and nonprecious dental casting alloys for the porcelainbaked‐ to‐metal technique have been determined. The semi‐precious alloys contained only 50 % gold, and palladium, silver, and some base metals. The nonprecious alloys were of the nickel‐chromium type. Discs and miniaturized tensile bars have been cast and tested either in the as cast condition, or after a simulation of the various porcelain bakes. Proof stress, ultimate tensile strength, elongation, and plastic stiffness have been measured and results compared by use of analyses of variance. The microstructure examination shows that the simulation of the porcelain bakes improves the homogeneity of the precious and semi‐precious alloys. Simultaneously, the mechanical properties of the same alloys are also improved. One semi‐precious alloy, still under development at the time of these tests, has its mechanical characteristics markedly dovv'ngraded by the thermal treatments. The nickel‐chromium alloys exhibit the best range of mechanical properties for the porcelain‐baked‐to‐metal technique, when considering the three most relevant properties: proof stress, plastic stiffness, and modulus of elasticity.
Some electromyographic parameters of experimental tooth clenching in adult human subjects
Authors: CHRISTENSEN L. V. 
Published: June 2007

SummaryEight adult human subjects exercised maximal voluntary tooth clenching until fatigue and pains were experienced, and could no longer be endured, in the right masseter muscle. The integrated electrical activity in the right masseter muscle was determined as a ratio of the different isometric exercises, and it showed a consistent decrease from onset of fatigue, via onset of pains, to the endurance of pains, possibly because of progressive muscle fatigue. The relative muscle activity might have determined the perception of the moment of onset of fatigue in the masseter muscle, and the perception of the moment of muscle exhaustion, but not the perception of the moment of onset of muscle pains.
Prevalence of symptoms of functional disturbances of the masticatory system in Swedish men
Authors: INGERVALL BENGT , MOHLIN BENGT , THILANDER BIRGIT 
Published: June 2007

SummarySubjective and clinical symptoms of mandibular dysfunction and cuspal interferences were studied in 389 Swedish men (median age 32 years).Impaired chewing function was noted in about 10%, different types of parafunction in 26%, frequent headaches in 5 %, TMJ or muscle pain in 3 % and difficulties in mouth opening in 10% of the men.Locking or luxation of the mandible was the most prevalent clinical symptom (24%), followed by reduced movement capacity and deviation on opening of the mandible, TMJ‐sounds and muscle tenderness. Sixty per cent of the men had one or more clinical symptoms of dysfunction.Subjective symptoms of dysfunction were positively correlated with reduced movement capacity of the mandible and tenderness of the masticatory muscles and temporomandibular joints upon palpation.Positive correlations were found between subjective symptoms of dysfunction and non‐working side interference as well as single tooth contact on the working side. Locking or luxation of the mandible and TMJ‐sounds were positively correlated with single tooth contact on the working side and TMJ‐sounds and muscle tenderness with interferences in the retruded position of the mandible.
A theoretical and clinical investigation into the taper achieved on crown and inlay preparations
Authors: MACK PETER J. 
Published: June 2007

SummaryThe minimum angles of taper that can in theory be formed to various preparations were established for representative dental preparations and operating distances.These values were compared with the taper of dental preparations formed both under laboratory conditions and in clinical practice, the latter by measurement of taper on the dies of clinically successful crowns and inlays.A possible explanation for the discrepancy noted between recommended degrees of taper and the tapers produced under clinical conditions was considered to be due to the requirement by a dental surgeon to avoid forming undercuts to the line of withdrawal of a cast intracoronal or extracoronal retainer.
The distribution of nickel in mice.
Authors: BERGMAN B. , BERGMAN M. , MAGNUSSON B. , SöREMARK R. , TODA Y. 
Published: June 2007

SummaryMetallic restorations are corroded in the oral environment. Corrosion products penetrate into the tissues and are distributed thssroughout the body seeking certain organs and tissues as targets.The distribution patterns of nickel in albino mice were studied autoradiographically at various periods after an intravenous injection of 63Ni in order to locate the target organs and tissues of nickel.Wth short survival periods the highest uptake of 63Ni was found in the blood, kidney, urinary bladder, lung, eye and hair follicles. With long survival periods, 3 weeks, the distribution pattern was dominated by high uptake in the lung tissues, central nervous system, kidneys, hard tissues and skin.The distribution pattern in brown mice was similar to that in albino mice. However, the concentration in the eye and the skin was more pronounced. The importance of release of nickel from nickel containing dental alloys in nickel allergic patients is discussed.
The prevalence of temporomandibular joint disturbances in complete denture patients
Authors: CHOY EUGENE , SMITH DALE E. 
Published: June 2007

Summary‘Complete denture patients do not suffer from TMJ disturbances’ is a statement commonly accepted by many dentists and clinicians. This statement is not valid since few dentists include a TMJ examination among routine clinical procedures for complete denture patients. Identification of an edentulous patient with TMJ disturbances is not possible with just a visual examination or the use of a TMJ questionnaire.The purpose of this investigation was to examine a group of 160 complete denture patients and determine the prevalence of TMJ disturbances among this sample of former and current patients at the University of Washington. The study included a TMJ questionnaire of eighteen questions to test its usefulness in identifying TMJ patients among the sample. All data from the clinical examination were programmed, punched, and processed on a CDC 6400 computer and correlated to selected dependent variables of the questionnaire.The conclusions from this investigation revealed:(1) Approximately 15% of the complete denture patients in this sample had TMJ disturbances.(2) The use of this questionnaire was not very reliable as a primary method of identifying TMJ patients, but it could be useful in screening potential TMJ patients.(3) Routine examination of complete denture patients should include palpation of the head and neck, and TMJ.(4) Complete denture patients have TMJ disturbances characterized by muscle tenderness, joint sounds, or restricted movements. They may not necessarily be associated with pain.(5) The lateral pterygoid muscle is the most common muscle involved with TMJ disturbances in complete denture patients.
On the regulation of interincisor bite force in man
Authors: HELLSING GUSTAF 
Published: June 2007

SummaryThe maximum bite force and the ability to perform a requested interincisor bite force was tested on eight healthy subjects with normal dentition and on five full denture wearers under various conditions.Anaesthesia of temporomandibular joint (TMJ) capsular and/or periodontal receptors, with or without simultaneous vibration‐induced increase of muscle receptor discharge, did not lead to noticeable changes in these capacities.It is concluded that in maximal voluntary efforts, as well as in trained and pre‐patterned motor acts, the motor activity may function without significant involvement of peripheral feedback mechanisms. However, all subjects significantly underestimated their bite force in the test series.Another conclusion from the present study is that neither jaw open nor jaw elevator vibration is of any influence upon the maximum bite force. On the other hand, the maximum bite force significantly increased after the performance of the test series.
The effect of some components on the rigidity of mandibular bilateral free end saddle dentures
Authors: GLANTZ P.‐O. , STAFFORD G. D. 
Published: June 2007

SummaryOne partially dentate person, his remaining teeth being 44, 43, 42, 41, 31, 32 and 33, was simultaneously provided with one maxillary complete denture and three mandibular free end saddle dentures having cobalt chromium alloy skeletons of different design. One denture was constructed with a lingual plate, another with a sublingual and a secondary bar, while on a third denture the major connector consisted of an enlarged secondary bar. On all the dentures occlusal rests were placed on teeth nos 44 and 33.Rosette strain gauges were placed in the midlines of all the major connectors. The gauges were calibrated on the master cast placed in a universal testing machine.The clinical recordings were taken from the gauges during one session under repeated loading conditions. Readings were repeated on one denture after removal of (1) the secondary bar and (2) the secondary bar and the occlusal rests. The recordings were used to calculate (I) the principal maximum and minimum strains and (2) the direction of the strains at the points of the bases beneath the centre of the gauges.The results show that studies of relevant functional deformation patterns of dentures can only be made in clinical experiments. Further, they show that the base with an enlarged secondary bar exhibits more deformation than the other two types of base. Removal of the secondary bar did not significantly increase the deformation of the denture also equipped with a sublingual bar, neither did the removal of the occlusal rests. Both these changes, however, caused changes of the deformation patterns.
Flow rate, sodium and potassium concentration in mixed saliva of complete denture‐wearers
Authors: GABAY EVA LANTZMAN 
Published: June 2007

SummaryFlow rate, sodium and potassium concentrations in stimulated mixed saliva obtained from eleven elderly (mean age 63) inexperienced denture‐wearers, were determined. Salivary samples were collected at four different dental stages:1. Before tooth extraction. 2. After tooth extraction.3. Three weeks after wearing newly constructed complete dentures.4. Following one year of denture wearing.Plasma electrolytes were included for comparison. The salivary sodium and potassium concentrations varied from stage to stage without showing corresponding variations in sodium and potassium in the blood. This points to selective action and an active transport system in the salivary cells. The mean flow rate and salivary electrolyte concentration showed a definite significant rise following the wearing of new complete dentures as compared with the previous dentulous and edentulous stages (Period A, non‐denture‐wearers). The mean flow rate was 2 ml/min after denture‐wearing compared to 0‐75 ml/min at the dentulous and edentulous stage (Period A). The stimulant effect represented by the dentures was found to be even more pronounced after one year. Mean sodium and potassium concentration at Period A were at levels of 5.50 and 13.67 mequiv /I respectively, as compared to levels of 23.72 and 19.40 mquiv./l respectively, after insertion of dentures. The difference was significant at a level of P<0.005. Although sodium concentration correlated well with flow rate, potassium concentration did not show any correlation with variations during secretion, following the wearing of dentures.
Capillary rheology of two composite resin systems
Authors: WATTS D. C. , COMBE E. C. , GREENER E. H. 
Published: June 2007

SummaryThe rheological properties of two commercial resin systems, Isopast and Cosmic, were studied in the shear rate range 0.65‐65 s−1 by capillary techniques. Isopast represents a low inorganic filled composite, whereas Cosmic is a conventionally filled system whose resin matrix resembles that of Isopast. All components of both systems obeyed power law dependence of shear stress as a function of shear rate according to the relation In τ= In K + n In γ; values of n for Cosmic catalyst and paste and Isopast paste were of the order of 0.6 whereas Isopast catalyst was of the order of 0.3. Setting systems obeyed a power law relationship during the working time with an exponent n≃0.7‐1.0. Accordingly the systems appear pseudoplastic in component form and slightly pseudoplastic to near Newtonian after mixing.
A simplified technique for determining the occlusal plane in full denture construction
Authors: SPRATLEY MARTYN H. 
Published: June 2007

SummaryBecause of difficulties encountered by students in determining the occlusal plane at the registration stage of full denture treatment, a simple technique which can be easily taught has been devised. Review of literature revealed a wide variety of landmarks and techniques advocated by various authorities and these are discussed. A technique using direct vision is described and a review of a series of patients showed it to be valid for the majority of cases.
The in vitro effect of a glass ionomer cement on dentine and enamel walls
Authors: WESENBERG GRO , HALS EINAR 
Published: June 2007

SummaryGlass ionomer cement (ASPA®) was inserted in unconditioned class V cavities or in contact with polished ground surfaces of enamel and dentine in twelve teeth. Ground sections of all teeth were examined by microradiography, and four of the sections submitted to electron probe microanalysis. A narrow outer zone of increased radiopacity in the dentine walls was explained by a 5−10% increase of Ca and P. In some sections this zone covered a partly demineralized subsurface zone. The concentrations of F and Al in enamel and dentine were ∼0.3% and 1.5%, respectively, decreasing to <0.1 % at a distance of 16–80 μm (F) and 8–24 μm (A) from the surface. Both F and Al penetrated deeper into the dentine than into the enamel. Decreased Zn values, sometimes concomitant with increased Ca, P and Mg values, were in some instances observed in an outer narrow zone of the dentine walls. It is assumed that like silicate cement, glass ionomer cement must have anticariogenic properties, due to uptake of F and Al in cavity walls.
The energy requirement of the dental cutting process
Authors: WESTLAND IR A. N. 
Published: June 2007

SummaryThe results are presented of research into the efficiency of various forms of dental burs. This research was carried out at the Delft University of Technology in collaboration with the Subfaculty of Dentistry of the Free University of Amsterdam. The process efficiency was measured during burring of both human teeth and amalgam plugs, with diamond burs and tungsten carbide burs at different speeds and diameters of the bur. Only the efficiency of the cutting process was evaluated, disregarding a number of other essential aspects of the burring process, such as the remaining surface quality after burring and the vibrations generated during burring.
The effect of salivary contamination on fissure sealant—enamel bond strength
Authors: THOMSON J. L. , MAIN C. , GILLESPIE F. C. , STEPHEN K. W. 
Published: June 2007

SummaryThe effect of accidental salivary contamination on the retention of fissure sealants is investigated via in Vitro bond tests and scanning electron microscopy. The strength of the bond between sealant and saliva contaminated and washed enamel (168 ± 14 kg cm−2) is not found to be significantly different from the bond strength to uncontaminated enamel (174 ± 17 kg cm−2). Unwashed contaminated enamel gives significantly reduced bond strength (68 ± 11 kg cm−2).