bluuebunny/crossref_metadata_2025 huggingface dataset:
A biometric comparison of face shape with denture tooth form
Authors: SELUK L. W. , BRODBELT R. H. W. , WALKER G. F.
Published: June 2007

Dentist and patient preferences are often used to select replacement teeth in prosthodontics. Face shape compared with inverted tooth form classifications based on Leon Williams's work are currently used. Shapes of teeth and faces have been referred to as square, ovoid or tapered, or some combination of these.

Six patients, three male and three female, were selected as being classically square, tapered or ovoid in facial form. Three sets of dentures had been made for each patient with tapering, ovoid and square denture teeth. Using a standardized photographic technique, full face views with profiles and close‐ups of the teeth were taken. Then from standardized enlarged tracings, key anatomic and derived points were marked, digitized and computer analysed. The face shapes and inverted tooth forms were digitized in the same manner.

A comparison of tooth moulds versus the actual denture teeth shows a highly significant difference (P<0.001) between set and unset denture teeth. There is also a significant difference (P<0.001) between facial form and denture teeth using temporal zygomatic and gonial widths for faces, compared with incisal, contact, and cervical widths for the teeth.
Denture stomatitis: a review
Authors: ARENDORF T. M. , WALKER D. M.
Published: June 2007

Denture stomatitis has been reported in 11–67% of complete denture wearers. It is more common on the palatal mucosa and in female patients. In Newton's type I denture stomatitis, where the inflammation remains focal, trauma seems to be responsible. In Newton's types II and III denture stomatitis, where the denture‐bearing mucosa is diffusely involved, most workers assert that the aetiology is multi‐factorial. Evidence is presented incriminating Candida albicans colonization of the fitting surface of the prosthesis in many cases of denture stomatitis promoted by continuous denture wearing. Allergic and primary irritant reactions to the denture base material, systemic predisposing factors including dietary deficiency and haematological disorders, also play a part. In most cases of denture stomatitis, elimination of denture faults, control of denture plaque and discontinuous denture wearing are sufficient treatment. The routine use of antiseptic or antimycotic drugs seems unnecessary.
The influence of enamel prism orientation on leakage of resin‐bonded restorations
Authors: CRAWFORD P. J. M. , WHITTAKER D. K. , OWEN G. M.
Published: June 2007

A new method is described for the quantification of leakage between etched enamel and restorative resin. A significant correlation was demonstrated between the plane of enamel section prior to etching and subsequent leakage. It is suggested that these findings will be of value in the design of cavities for use with the acid‐etch technique; when possible, enamel should be prepared to expose prisms transversely prior to etching and bonding.
Stability of ceramic pigments for maxillofacial applications
Authors: SELUK L. W. , YU R. , KORAN A.
Published: June 2007

In this study samples made from pigmented porcelain and Silastic 44210 were evaluated for colour stability after accelerated ageing in order to determine the potential of coloured ceramic powders as maxillofacial pigments. These pigments demonstrated good clear colour stability compared with the same pigments which were not incorporated into a porcelain matrix.
Subjective need of removable denture treatment in Finnish adults
Authors: NYYSSÖNEN V. , LAPPALAINEN R. , HONKALA E. , MARKKANEN H. , PAUNIO I.
Published: June 2007

The aim of this study was to analyse the clinical dental health, use of dental services and socio‐economic factors correlating with the subjective need for removable dentures in Finnish adults aged 30 years and older. A total of 2528 persons who had lost one or more natural teeth (wisdom teeth excluded) and who had not been provided with any dentures, were selected for this study. Subjects who had subjective need for prosthetic treatment had statistically significantly fewer teeth and fewer fillings, and more decayed teeth than others. Irregular users of dental services felt the need for a prosthesis more often than did regular users of those services. Irregular brushing of teeth was also associated with a greater need for prosthetic treatment. Men, older individuals and persons with less education and a smaller family income felt the need for prosthetic treatment more often than women, younger individuals and better educated persons.

The factors differentiating between the two groups with and without a subjective prosthetic treatment need were analysed by discriminant analysis. The best differentiating factors were frequency of dental visits, caries score, frequency of brushing teeth, family income, number of fillings and sex.
Occlusal interferences related to dental panoramic radiographic changes in subjects treated with fixed prosthesis
Authors: ETTALA‐YLITALO U.‐M. , SYRJÄNEN S. , MARKKANEN H.
Published: June 2007

Because of contradictory reports between clinical and radiographic findings, occlusal analysis correlated to dental panoramic findings was completed in 147 patients treated with fixed prosthesis. Both occlusal interferences and radiographic changes in the TMJ area and/or in dentition were frequently discovered. Dysfunction and occlusal indices gave statistically significant correlations to radiographic changes (P<0.01 and P<0.05, respectively) in the TMJ area. Periodontal changes with vertical bone pocket formation and sclerotic lamina dura seem to be early radiographic findings and occlusal interferences were the only means to give a clear‐cut correlation to the radiographic changes (P<0.001). However, if periodontal tissues with supporting bone structure fail to respond to occlusal trauma, changes in the TMJ area will probably appear. From the clinical changes the deviation on mouth opening, tenderness to palpation of TMJ, and slide from retrusion to intercuspidation (RP–IP) explained most of the radiological TMJ changes when tested by the discriminant analysis. The value of radiographic follow‐up of subjects following prosthetic treatment is emphasized.
Anatomical and electromyographic studies of the lateral pterygoid muscle
Authors: WIDMALM S. E. , LILLIE J. H. , ASH M. M.
Published: June 2007

The relationships of the lateral pterygoid muscle within the infratemporal fossa were observed by conventional dissections and by examination of specimens sectioned in the horizontal and frontal planes. The following less well‐known features were noted. At the origins of the superior and inferior heads there are regions in which the fibres are interlaced or closely overlapped by fibres of either the temporalis muscle or the medial pterygoid muscle. Fibres of the superior head insert not only into the meniscus of the temporomandibular joint, but also into the pterygoid fovea at the neck of the mandibular condyle. Specimens sectioned through the origin of the inferior head of the muscle show internal tendon lamellae consistent with a pennate structure.

Electromyographic (EMG) activity was recorded in five healthy subjects using concentric needle and fine‐wire electrodes. Strong to very strong activity was consistently observed in the superior head during clenching and tooth gnashing. The inferior heads were silent or had negligible to slight activity most of the time during ipsilateral movements or clenching, but were co‐activated bilaterally, with strong to very strong activity during jaw opening, protrusion, swallowing, tooth gnashing and during passive retrusion. They showed marked activity unilaterally during contra‐lateral movements.
An evaluation of a lathe‐cut high‐copper amalgam alloy
Authors: KNIBBS P. J. , PLANT C. G. , SHOVELTON D. S. , JONES P. A.
Published: June 2007

Modification of an amalgam alloy may give rise to improved physical properties. The physical properties of a newly formulated, single‐composition lathe‐cut amalgam alloy were studied and found to be superior to those of a conventional lathe‐cut amalgam alloy. However, such modification in formulation may result in changes in the clinical handling properties of the material. The high‐copper amalgam alloy was assessed by a panel of general practitioners who found that the general handling properties of the material were similar to those of conventional lathe‐cut amalgam alloys.

The longer term performance of the high‐copper alloy was assessed by means of a blind, controlled clinical trial carried out by two operators. A 1‐year assessment of the resulting restorations and tooth replicas could not distinguish between the high‐copper alloy and a conventional alloy. The two alloys had both given good clinical results.
Mandibular dysfunction in an institutionalized and predominantly elderly population
Authors: MacENTEE M. I. , WEISS R. , MORRISON B. J. , WAXLER‐MORRISON N. E.
Published: June 2007

Oral health problems were identified among 653 residents of 40 long‐term care institutions in Vancouver, using a personal interview and a dental examination. Information on jaw function was analysed as part of this investigation to identify associations between the clinical signs of mandibular dysfunction and the complaints of the subjects, their occlusal instability, and the quality of their dentures. The sample population were predominantly female and over 75 years of age, and 42% had some natural teeth. Complaints of jaw dysfunction, usually sore muscles, were heard from 13% of the 488 subjects interviewed. The examination was performed on all of the subjects and revealed that 43% had unstable occlusal contacts, 37% were using loose or unstable dentures, and 20% had one or more clinical signs of jaw dysfunction. Joint noise was the most frequent sign detected and it was heard in a greater percentage of the women than men, while deviation of the mandible during mouth opening was observed with great frequency in the younger age groups. There was no apparent association found between the clinical signs of jaw dysfunction and the complaints of the subjects or the condition of their teeth or dentures. The study demonstrated that complaints and clinical signs of jaw dysfunction, with the exception of joint noises, were uncommon in this population.
The plastic cap—an improved technique for impression taking
Authors: FITZIG S. , ELI I.
Published: June 2007

An improved impression technique is described using a plastic, transparent, flexible cap in combination with silicone impression materials. The technique can easily be applied at the chairside by the clinician and provides a solution to some of the present problems in impression with minimal trauma to the surrounding tissues.
Follow‐up study of patients with bridge constructions performed by private dental surgeons and at a university clinic, 8 years following insertion*
Authors: ÖDMAN P. A. , KARLSSON S.
Published: June 2007

Patients treated in private practice and patients treated at the Department of Prosthetic Dentistry of the Faculty of Odontology in Gothenburg with fixed bridgework were questioned about their experience of their bridges. The interview was carried out with questionnaires and in some cases by telephone. The results were similar in both groups, and the patients were satisfied with the treatment.
Tissue response to implanted ceramic‐coated titanium alloys in rats
Authors: SATOMI K. , AKAGAWA Y. , NIKAI H. , TSURU H.
Published: June 2007

In order to assess the tissue compatibility of the hybrid materials for the dental implant (hydroxyapatite, titanium oxide and titanium nitride coated titanium alloys), tissue response to these materials implanted in the rat subcutaneous tissue was histologically examined. Initial inflammatory response was less evident in titanium oxide coated and non‐coated titanium alloys. All materials were encapsulated by thin fibrous connective tissues. The membrane thickness of hydroxyapatite coated titanium alloy was significantly higher than that of titanium nitride coated one. These results suggest that all materials possess favourable tissue compatibility and may encourage clinical use as the dental implant.
The effects of mixing capsule geometry on the early compressive strength of dental amalgam
Authors: PEARSON G. J. , ATKINSON A. S.
Published: June 2007

Three dental amalgams were mixed in a number of different mixing capsules. Compressive strength specimens were prepared using a clinically relevant technique and tested at 1 h and 7 days. The results showed that the early compressive strength of an alloy was influenced by the mixing capsule, and suggested that internal capsule geometry may be an important contributary factor in capsule performance. With one exception, there was a marked difference between the compressive strengths produced under the present method and those reported by manufacturers under test conditions laid down in standards specifications.
In vitro temperature rises during visible‐light curing of a lining material and a posterior composite
Authors: SMAIL S. R. J. , PATTERSON C. J. W. , MCLUNDIE A. C. , STRANG R.
Published: June 2007

The aim of this study was to measure the rise in temperature during: (i) a single cycle of a curing light unit, (ii) the polymerization of a layer of light‐cured lining material, and (iii) the polymerization of a light‐cured posterior composite material, and also during combinations of these individual procedures. Experimental work was undertaken in vitro and measurements were made using a thermocouple placed centrally in an insulated PTFE well. Large temperature rises occurred with the use of the curing light alone. The lining material itself did not contribute significantly to the rise in temperature during curing, nor did it provide thermal insulation from the output temperature emitted by the light guide. The presence of a layer of posterior composite reduced the temperature transmitted from the light but the residual temperature rise transmitted was still of such a magnitude as to cause concern regarding possible thermal injury to the pulp.
The value of the Gothic arch tracing in the positioning of denture teeth
Authors: EL‐GHERIANI A. S. , WINSTANLEY R. B.
Published: June 2007

Twenty‐five subjects of three nationalities carried out Gothic arch tracings. Measurements between the side arms were compared with the upper intercuspid distances measured in the same subjects. A relationship was found which may be of value in the setting up of anterior maxillary denture teeth.
The effect of variation of residual ridge angle on partial denture abutment tooth movement
Authors: FEINGOLD G. M. , GRANT A. A. , JOHNSON W.
Published: June 2007

Using a laboratory model simulating a free‐end saddle partial denture situation, the effect of variation of the angulation of the crest of the residual alveolar ridge to the horizontal on movement of the abutment tooth and saddle was observed. It was found that the inclination of the residual ridge affected the direction and magnitude of abutment tooth movement. The direction of abutment tooth movement was not related to the position of the occlusal rest. However, the magnitude of saddle and abutment tooth movement is affected by the design of the clasp used.
Determination of vertical dimension by hydraulic intraoral jack
Authors: LoSCHIAVO M. , MADHAV S. , WHYMAN R.
Published: June 2007

This paper describes the application of a hydraulic intraoral jig to the establishment of the vertical dimension of occlusion for full denture construction. The device enables the patient to establish an occlusion height which is most comfortable without the intervention or guidance of the dentist. Six patients for whom new dentures were to be constructed in the University of Otago School of Dentistry were invited to participate in the study. A conventional technique of denture construction was employed, but an additional stage was introduced after the jaw records had been taken and the casts mounted. Each patient was instructed in the use of the hydraulic jig and was asked to find a comfortable bite height in his own time. The results were compared with occlusal heights determined by conventional subjective methods. The former results proved to be more repeatable than those utilizing rest position and an average free‐way space. The results are discussed and the implications outlined. Suggestions for further research using the hydraulic jig are made and the authors conclude that the hydraulic jig may be used to determine vertical dimension for full denture construction.
Inhibition of bacterial colonization by antimicrobial agents incorporated into dental resins
Authors: BAPNA M. S. , MURPHY R. , MUKHERJEE S.
Published: June 2007

The antimicrobial activity of several chemical agents was determined by incorporating these agents into dentine adhesive resin and following the colonization of Streptococcus mutans on the surfaces of the resin and culture vessel, as well as in the surrounding medium, by optical density measurements. It was found that sodium fluoride and dodecylamine, an organic amine, exhibited excellent antimicrobial properties. These chemicals not only inhibited bacterial growth completely but also seemed to reduce the adhesion of the bacteria to the resin surface. A silver compound, protargin, was mildly effective in inhibiting growth ofS. mutans. Copper oxide and chelating acids such as vanillic acid, syringic acid, and ethylenediamine‐n, n'diacetic acid (EDDA) were not effective as antimicrobial agents againstS. mutans.
Signs and symptoms of mandibular dysfunction in shortened dental arches*
Authors: WITTER D. J. , VAN ELTEREN P. , KÄYSER A. F.
Published: June 2007

In this study subjects with shortened dental arches (SDA, n=60), characterized by the absence of molar support, are compared with subjects with a complete dentition (n=72) with respect to signs and symptoms of mandibular dysfunction.

The subjective examination consisted of questions related to pain, noises within the joints and mobility of the lower jaw. The objective examination consisted of the registration of clicking of the temporomandibular joint (TMJ) by bilateral palpation and measuring the maximal mouth opening.

In spite of the finding that significantly more subjects of the SDA group under 40 years of age reported pain in or around the TMJ, it is concluded that in the population studied no convincing evidence was found that a SDA provokes signs and symptoms of mandibular dysfunction.
Histological and histomorphometrical analysis of bioactive glass and fibre reinforced bioactive glass dental root implants
Authors: SCHEPERS E. , DE CLERCQ M. , DUCHEYNE P.
Published: June 2007

Bioactive glass has the ability to bond with bone, but it cannot be used as a load bearing device due to its limited mechanical properties. By reinforcing bioactive glass with a ductile second phase, a structurally reliable material is obtained.

The aim of the present study was to evaluate histologically and morphometrically the interfacial behaviour of submerged composite dental root implants. Therefore, bulk and composite implants were subgingivally installed in the partially edentulous jaws of Beagle dogs and harvested after 4 and 16 months.

Histologically, the connection between the implants and bone tissue could be clearly demonstrated. This bone connection is mainly located at the cortical bone level. In the vicinity of the infraalveolar nerve a fibrous tissue contact was found.

It is shown that surgical trauma, motion at the glass to tissue interface, and gross ion dissolution from the material adversely affect the interfacial osteogenesis. If these factors are controlled, bone bonding is found over a larger area than the initial area of contact between the implant and bone tissue. This means that bone grows out along the implant surface, starting from the initial contact area.

No difference was observed between the interfacial behaviour of bulk bioactive glass and intact fibre reinforced bioactive glass implants.
Condition of prosthetic constructions and subjective needs for replacing missing teeth in a Finnish adult population
Authors: TERVONEN T.
Published: June 2007

Prosthetic treatment needs were studied in a sample of 1600 adults distributed equally into cohorts aged 25,35,50 and 65 years. A total of 1275 subjects (80%) were clinically examined with respect to the condition and age of existing prosthetic constructions, subjective needs for replacing missing teeth and the frequency of oral mucosal lesions associated with the wearing of dentures. Approximately half of the removable dentures (56%) were objectively non‐acceptable and one‐third (36%) subjectively so. One in four of those subjects with missing anterior teeth and premolars, or with 0–2 remaining mandibular molars and one in five of those with 0–2 remaining maxillary molars expressed a need to have one or more of the missing teeth replaced. The replacement needs were slightly greater for missing anterior teeth and premolars than for molars. Subjective needs for replacing missing teeth were greatest at the age of 50 years. The condition of removable dentures according to objective assessment was poorest among those aged 65 years. A high frequency of mucosal lesions associated with old and non‐acceptable removable dentures was observed.
Wearing of removable partial dentures in relation to dental caries
Authors: TUOMINEN P. , RANTA K. , PAUNIO I.
Published: June 2007

Using a representative sample of 5028 dentulous Finnish adults the occurrence of dental caries was studied among removable partial denture (RPD) wearers and non‐wearers. Of the subjects wearing no RPD(s) 61·4% had one or more carious teeth, among those wearing a single RPD the figure was 60·5% and among those wearing RPDs in both jaws 62·7%, respectively. When sociodemographic background, other oral status measures than caries and oral health care habits were simultaneously controlled, subjects wearing RPDs in both jaws had slightly increased (P≥0·05) probability of having one or more carious teeth compared to those with no RPD(s). Subjects with a single RPD did not have a statistically significantly increased probability of having carious teeth. Among those 3075 subjects who had one or more carious teeth the wearing of one or two RPDs did not significantly increase the number of carious teeth. Because the subjects wearing RPDs in both jaws were seen to have a slightly increased risk of having caries, this confirms the view that dentists should emphasize good oral hygiene habits and regular dental attendance among RPD wearers.
Bulk fracture of amalgam restorations—a 5‐year controlled clinical trial*
Authors: LEMMENS P. L. M. , LETZEL H. , PETERS M. C. R. B. , VAN'T HOF M. A. T.
Published: June 2007

A controlled clinical study, containing 720 posterior amalgam restorations placed in a group of 103 adult patients by three dentists, was used for examination of the influences on the incidence of occlusal and approximal bulk fractures. These fractures were evaluated from black and white photographs, taken annually, of the occlusal surface of the restorations over a 5‐year period, using a three point photorating scale for both fracture sites.

The influence of the dentist as well as the influence of the alloy and tooth type were statistically analysed. The results of these analyses demonstrated that the dentist, as well as the alloy and tooth type, have a statistically significant influence on the incidence of bulk fracture of amalgam restorations.
Tooth wear measurements using a reflex microscope
Authors: ADAMS L. P. , WILDING R. J. C.
Published: June 2007

The resistance to wear of composite resins is an important feature of their suitability for use as posterior restorative materials. The in vivo clinical evaluation of new materials requires an accurate and reliable method of assessing tooth wear. The purpose of this study was too investigate the possibility of using a new stereometric measuring instrument for this purpose. Tooth wear was experimentally produced on a lead cast. The volume and average depth lost was measured using a reflex microscope. A gravimetric method of wear measurement was used as a control. When the results of both methods were compared it was found that the mean difference in depth of wear measured between the two methods was 10 μm. The reflex microscope appears to be ideally suited to making objective comparisons between the wear characteristics of composite resins.
Finite element analysis of a mandibular model
Authors: FARAH J. W. , CRAIG R. G. , MEROUEH K. A.
Published: June 2007

A two‐dimensional finite element model of a mandibular quadrant was used to examine the stresses and displacements resulting from a 100 N load placed as follows: (i) distributed on the second molar, (ii) concentrated at 30° to the vertical on the second molar, and (iii) distributed on the second premolar and second molar. Each tooth was supported by periodontal ligaments, cortical and cancellous bone. The modulus and Poisson's ratios for each material were selected from accepted values. The principal stresses were determined throughout the model, with special emphasis being placed for elements in the immediate vicinity of the teeth mentioned above.

It was found that for the case where the load was uniformly distributed on the second molar the stresses σmain were mostly compressive (–) in nature while σmax were mostly tensile (+). In the case where the load was concentrated and at 30° to the vertical, the magnitude of the stresses were three to five times greater and the pattern less uniform than those resulting from the distributed load.

The concentrated load at 30° to the vertical resulted in higher bending stresses than the distributed load and hence higher σmax stresses.
Physical properties of addition silicones as a function of composition
Authors: WILLIAMS J. R. , CRAIG R. G.
Published: June 2007

The effects of molecular weight of the base silicone, filler and copolymer concentrations on compression set, strain, creep and dynamic elastic modulus were determined. The molecular weight of the base silicone had the least effect on these properties although low molecular weights showed better properties. Chain extenders were detrimental to physical properties of creep, compression set and dynamic elastic modulus. Increased copolymer concentrations decreased compression set, strain and creep and increased the dynamic elastic modulus. The useful copolymer/base functional group ratio was from 1:1 to 3:1. Filler affected properties to a lesser extent than copolymer ratio. Compression set, strain, and creep decreased and the dynamic elastic modulus increased with increasing filler with the properties being directly proportional to the weight fraction. All properties were interrelated with In strain linearly related to In compression set, creep proportional to set, and the dynamic elastic modulus was inversely correlated with strain and creep.
History factors associated with symptoms of temporomandibular disorders
Authors: PULLINGER A. G. , MONTEIRO A. A.
Published: June 2007

Differences in prevalence of head or neck trauma, orthodontic treatment and molar oral surgery procedures reported by individuals were compared among patients with temporomandibular disorders (TMD) and with two comparison groups (a sample of asymptomatic individuals, and a sample with mild or early signs). Association to specific TMD symptoms was tested amongst the comparison groups.

Trauma was the most significant factor characterizing TMD patients. History of trauma was also more common among those otherwise normal but symptomatic individuals in the non‐patient comparison group. Specific TMD symptoms were significantly associated with history of trauma in the comparison group. Significantly more women TMD patients had a history of orthodontic and molar oral surgery treatment than the asymptomatic comparison group. History of orthodontics was also associated with the symptomatic sample of the comparison group in women, but it was not significantly related to any specific TMD symptoms. Symptomatic members of the comparison group could not be differentiated based upon history of molar oral surgery.

Certain risk factors may have been delineated, but causal relationship of treatment requires study of co‐existing and predisposing behavioural and structural factors.
Relationship of first primary palatine rugae to the maxillary canines in man
Authors: GROVE H. F. , CHRISTENSEN L. V.
Published: June 2007

Fifty dentate maxillary casts, obtained from thirty‐four males and sixteen females, were mounted in the three‐dimensional co‐ordinate system of a contour meter. A transverse line of reference (x‐axis) was drawn through the distal contact points of the maxillary canines, at a right angle to the y‐axis which passed through the contact points of the maxillary central incisors. Relative to the canine‐to‐canine baseline, the locations of the lateral borders of the right and left first primary rugae were determined. The rugae were distributed on both the anterior and posterior sides of the baseline, and the anterior and posterior distances from the baseline were on the average about 1 mm. The age of the subjects, ranging from 12 to 52 years, appeared to be unrelated to the frequencies of anteriorly and posteriorly positioned rugae. Right and left first primary rugae, located on the anterior side of the baseline, showed a minute asymmetry in their topography. By contrast, there was topographical symmetry when the rugae were located on the posterior side of the baseline.
Colour effect of denture base on denture tooth materials
Authors: MILLSTEIN P. L. , HARLAN J. , NATHANSON D.
Published: June 2007

A study using a HunterLab colorimeter was conducted to determine the colour effect of denture base materials on denture tooth acrylics.

The results show that denture base materials create a measurable change in the chroma of denture tooth acrylics and suggest that optimal shade selection of teeth should include a determination of the background effects of denture base materials.
Electromyographic studies of craniomandibular disorders: a review of the literature
Authors: DAHLSTRÖM L.
Published: June 2007

Craniomandibular disorders have been investigated from many points of view, structurally and functionally. To evaluate the behaviour of the masticatory muscles, electromyography (EMG) has been widely used and the studies have emanated from many different paradigms. The purpose of this paper is to review articles in which EMG has been used to study symptomatic subjects.

Findings from sleep studies and basic laboratory studies seem to support the hypothesis of a correlation between masticatory muscle hyperactivity and symptoms. Experimentally induced stress studies consistently show an increased activity in symptomatic subjects.

Investigations of motor pauses, the often lengthened silent period, are summarized and discussed. Several different treatment strategies, particularly splints and biofeedback, have been evaluated using EMG, indicating a normalization, but controlled outcome studies are sparse. The use of EMG has thus substantially increased our knowledge of dysfunction of the masticatory system.
Real‐time signal acquisition and analysis for clinical dental electromyography using a microcomputer‐based system
Authors: YUEN S. W. H. , MA R. Y. P. , CHUNG Y. C. , HWANG J. C. C.
Published: June 2007

The Electromyographic (EMG) Signal Acquisition and Analysis System is an integrated hardware and software system that digitizes multichannels of amplified EMG signals and stores them in user defined disc files before analysis. The software runs on all IBM PC and its compatibles with the appropriate analogue‐to‐digital (A/D) conversion board. Both time and frequency domain analyses can be computed on‐line. This system provides a low cost method of digitizing and analysing EMG signals on real‐time for clinical dental electromyography.
Oral pathology and prostheses—are they related? Investigations in an elderly population
Authors: HOAD‐REDDICK G.
Published: June 2007

A survey of 233 elderly subjects living in the district served by the Halton Health Authority (Cheshire, England) investigated the relationship between the age of dentures, their need for replacement and the presence of any oral pathological lesions. The retention, stability, occlusion and cleanliness of the dentures were all found to be worse in the older appliances; perceived need for denture replacement was found to increase from 40% in 5‐year‐old dentures to 84% in dentures over 31 years old. While 41% of the sample had an oral pathological lesion, no significant relationship was found between denture age and pathology or place of residence. People resident in the community with no assistance had the highest incidence of oral pathology and those living in long‐stay hospitals the least. The absence of a relationship between denture age and oral pathology is considered to be a powerful indicator of the need for regular oral examination of the edentulous population.
The effects of cusp and jaw morphology on the forces on teeth and the temporomandibular joint
Authors: KATONA T. R.
Published: June 2007

Basic principles of engineering mechanics are used to solve for force vectors in the masticatory system. It was found that incisor guidance/cusp angulation, crown heights and the anterior‐posterior location of contact can significantly affect the magnitudes and/or directions of forces acting on contacting teeth and the temporomandibular joint. The results provide insight into the function of the jaws and the diagnosis and treatment of occlusion‐related trauma.
Preliminary studies of some masticatory characteristics of bruxism
Authors: FAULKNER K. D. B.
Published: June 2007

The masticatory cycles of bruxist subjects were studied using a closed‐circuit television movement detector. These cycles were compared with those of non‐bruxist subjects.

Early results indicate a shorter stationary period between masticatory cycles in all components of movement in bruxist subjects than in non‐bruxist subjects. Also, in some bruxists, the envelopes of motion showed quite irregularly shaped patterns, with sudden changes in direction, while others showed a loss of the classical teardrop pattern.
Spectral analysis of the masseter and anterior temporalis: an assessment of reliability for use in the clinical situation
Authors: BARKER G. R. , WASTELL D. G. , DUXBURY A. J.
Published: June 2007

The electromyogram (EMG) of contracting muscles can be analysed in the frequency domain by spectral analysis. However, there is a need to establish the reproducibility of spectral parameters such as mean power frequency (MPF) This study examined the variation of MPF (masseter and anterior temporalis) between and within recording sessions.

The MPF was found to be significantly reliable for both muscles, but considerable within‐subject variation was found despite comprehensive measures to standardize recording methods and conditions. It is concluded that MPF may have clinical application in the diagnosis and treatment of patients with facial pain arising from muscle dysfunctions, but caution should be exercised in interpreting small changes in frequency, given the inherent variability of MPF.
Dietary pattern, energy and nutrient intake in patients with oro‐facial discomfort complaints
Authors: YONTCHEV E. , SANDSTROM B. , CARLSSON G. E.
Published: June 2007

In ninety‐six patients with oro‐facial and general complaints, which the patients assumed were caused by galvanic currents and/or metallic restorations, the recording and analysis of dietary pattern, energy and nutrient intake were performed. The records, in household measures, of the intake of food and beverages during 7 consecutive days according to a written instruction were collected. Sixty‐eight out of the ninety‐six records were sufficiently complete for calculation of nutrient intake. The remaining twenty‐eight could only be used partially in the analyses.

Most of the patients had a varied food intake of all the food groups during the 7‐day period. The range was wide, however, and a few patients had relatively low intake of essential nutrients. It was not possible to find any correlation between oro‐facial discomfort complaints and intake of any single nutrient that could indicate a cause‐effect relationship. No correlation between diet pattern, energy and essential nutrients, and the measured electrode potentials of the fillings and constructions could be proved. Nor could the hypothesis that beverage intake might influence the electrode potentials and increase or aggravate the oro‐facial complaints be verified.
A new, simple and accurate method for evaluating masticatory ability
Authors: NAKASIMA A. , HIGASHI K. , ICHINOSE M.
Published: June 2007

A new method has been devised to measure masticatory ability. Pigment‐coated granules were prepared, and 730 mg (730–740 granules) were sealed in a rubber capsule. This capsule was used as a test material and was chewed by the subject under standardized conditions. The masticatory ability, defined as the joules of work performed, was calculated based on the concentration of pigment leaked from the crushed granules during the process of mastication. The procedure is rapid, simple and reliable, and can be used for a large number of clinical samples and studies. The measurement error, defined as the coefficient of variation, was 2.1%. The intraindividual variation of measurements of twenty volunteers ranged from 3.6 to 16.9%. A series of tests in each subject was necessary to obtain a reliable value of masticatory ability.
The OPG: an aid in TMJ diagnostics. III. A comparison between lateral tomography and dental rotational panoramic radiography (Orthopantomography®)*
Authors: HABETS L. L. M. H. , BEZUUR J. N. , LOPEZ V. JIMENEZ , HANSSON T. L.
Published: June 2007

In the comparison of radiographical findings (flattening, irregular surface and osteophyte formation) between lateral tomography and Orthopantomography(r) in thirty‐one female patients with craniomandibular disorders, a 76% similarity was found. A trend in the findings was seen: with an increase in radiographical findings visible in the tomograms there is a decrease in the amount of condylar asymmetry visible in the Orthopantomograms(r) and a decrease in the age of the patients.
The mandibular condyles in the submentovertex projection—their morphology and topographical relationship to the foramina spinosa
Authors: KRENKEL C. , GRUNERT I.
Published: June 2007

On conventional radiographs, the morphology and position of the condyles in an axial view are best seen in the submentovertex projection. The foramina spinosa, which are used by the middle meningeal arteries as passages and are clearly outlined in this view, serve as landmarks for a co‐ordinate system that permits precise measurements of various angles and distances.

One hundred and twenty‐six submentovertex views were used for measuring the condyles. Results presented as means and standard deviations suggest condylar variables to be related to the function of the stomatognathic system. Practical applications include surgical, orthodontic or prosthetic manipulations of the mandible resulting in transverse or sagittal displacement of the condyles.
Myodynamic and conventional construction of complete dentures: a comparative study of comfort and function
Authors: BARRENÄS L. , ÖDMAN P.
Published: June 2007

Function and comfort during wearing of myodynamically and conventionally constructed dentures were evaluated in 30 patients. All patients were fitted with one set of myodynamic and one set of conventional dentures. The neutral zone was recorded with a Xantopren® blue impression. Twenty‐three of the patients preferred the myodynamic dentures, two preferred the conventional dentures, two experienced no difference and three patients used a combination of the conventional and the myodynamic sets. There were also less post‐insertion problems with the myodynamic dentures compared to the conventional ones.
Human bite force discrimination using specific maxillary and mandibular teeth
Authors: COFFEY J. P. , WILLIAMS W. N. , TURNER G. E. , MAHAN P. E. , LAPOINTE L. L. , CORNELL C. E.
Published: June 2007

The purpose of this study was to determine whether performance differences existed in subjects'self‐generated bite force discrimination ability using maxillary and mandibular central incisors, canines, premolars and first molars. Two separate studies were conducted: (i) to assess whether performance differences existed in subjects'bite force discrimination ability using central incisors and premolars; (ii) to compare subjects'performance on bite force discrimination using central incisors, canines and first molars. Assessment of bite force was measured using a specially designed strain gauge scale allowing subjects to visually monitor when their biting force equalled a preset resistance. Resistance forces of 500, 1000 and 3000 g were selected as standards. Subjects were presented with a series of paired resistance settings, one at a time, the first of each pair being the standard and the second being the comparator setting of a predetermined amount. This paired‐comparisons procedure was continued until the subjects'difference limen (DL) value (the threshold of discrimination between two forces) could be established. The first study revealed no significant (P>0.05) overall difference in subjects'bite force discrimination ability relative to specific teeth. In contrast, in the second study a significant difference (P<0.05) was identified in subjects'performance relative to specific teeth; subjects performed better using central incisors compared to first molars. In both studies, subjects' performance was significantly better (P<0.05) using the 500g standard compared to the 3000 g standard in the first study, and compared to the 1000g standard in the second study. No significant differences (P<0.05) were observed between the performance of males and females in either study.
Diagnosis of caries and treatment decisions in approximal surfaces of posterior teeth in vitro
Authors: NOAR S.J. , SMITH B.G.N.
Published: June 2007

The diagnosis of caries and treatment planning decisions have been reported to vary widely between individual dentists. However, opinions differ as to whether, in general, this results in too much or too little treatment.

Eighty‐six dentists, mainly attending post‐graduate meetings, participated in this study. They were asked to make diagnostic and treatment planning decisions on a selection of extracted teeth set in realistic contact with each other. These decisions were compared with the appearance of the proximal surfaces before setting the teeth in contact, and the histological appearance of the teeth that were sectioned after the dentists had made their decisions.

Opinions as to whether caries was present and whether it required treatment showed a wide distribution. However, had the decisions been acted upon, between 1‐6% of the sound surfaces would have been filled, but 20–68% of teeth with clearly cavitated surfaces or histological evidence of dentine involvement would not have been filled.
Clinical evaluation of two posterior composite resins: two‐year results
Authors: STANGEL I. , BAROLET R.Y.
Published: June 2007

Two composite resins were evaluated for clinical acceptability as restorative materials in Class I and II cavities over a 2‐year period. In addition, dispersed phase alloy was evaluated for comparison. All restorations were assessed for anatomical form, marginal integrity and marginal leakage using modified United States Public Health Service (USPHS) criteria. At the 2‐year recall, 96% of the composites and 100% of the amalgams were rated ‘alpha’ or ‘bravo’, using the parameters of assessment defined in this study. However, a significant number of shifts from the baseline, within the level of acceptability, had occurred. The two composites showed the greatest number of shifts for anatomical form and marginal leakage, while there were no differences between the composites and the amalgam for shifts in marginal integrity. Although a very high level of acceptability was determined for all of the materials, the frequency of rating change within categories for the composites was a cause of concern with regard to their long‐term clinical use.
An evaluation of a rapid setting glass ionomer cement used by general dental practitioners to restore deciduous teeth
Authors: KNIBBS P. J. , PLANT C. G.
Published: June 2007

Twenty‐one general dental practitioners evaluated the clinical handling properties and performance of a newly formulated glass ionomer cement of the powder/water type. One hundred and eighteen restorations were placed. Sixty‐nine restorations were reviewed, on average, after 6 months by 17 practitioners who completed the trial. This formulation set rapidly. Approximately 90% of the restorations that were reviewed performed well over the period of assessment. The results of the trial were compared with those of trials on earlier glass ionomer cements used to restore deciduous teeth. The main advantage of the new formulation was the improvement in handling properties.
Finishing composite restorative materials
Authors: WILSON F. , HEATH J. R. , WATTS D. C.
Published: June 2007

A clinically realistic in vitro study was performed to determine the best method for smoothing trimmed surfaces of seven composite restorative materials. Soflex discs produced the smoothest surface, and little advantage appeared to be gained by prior smoothing of the surface with stones or points. A polishing paste, even when used with intermediate finishing agents, produced a rougher surface than that left by the discs.
Oral comfort in shortened dental arches*
Authors: WITTER D.J. , VAN ELTEREN P. , KÄYSER A.F. , VAN ROSSUM G.M.J.M.
Published: June 2007

In this study, the oral comfort was compared between subjects with shortened dental arches (SDA, n= 74), subjects with SDA and free‐end removable partial dentures (SDA + RPD, n= 25) and subjects with complete dental arches (CDA, n= 72).

Oral comfort was measured by (i) absence of pain or distress; (ii) chewing ability; (iii) appreciation of the appearance of the dentition. Additionally, the history of free‐end RPD over a period of nearly 7 years was taken into consideration.

On the whole, the results did not reveal any significant differences between the three groups with respect to pain or distress. Only 8% of the subjects with SDA reported impairment of chewing ability, and 11% had aesthetic complaints, due to missing posterior teeth in the upper jaw. Of the subjects with SDA * RPD, 20% had complaints about the RPD. In addition, the repeated necessity for repair or replacement of free‐end RPD and the fact that some subjects (20%) stopped wearing the RPD during the observation period, confirm the poor performance of this dental provision. It is concluded that the oral comfort of subjects with SDA in this study is compromised to a small extent but remains on an acceptable level. Free‐end RPDs do not appear to help oral comfort in these cases.
Further studies of mandibular movement at initial tooth contact
Authors: FAULKNER K.D.B.
Published: June 2007

By measurement of movement of the mandible immediately after tooth contact during tooth tapping tasks, it has been shown that patterns of direction are less regular in bruxist subjects than in non‐bruxist individuals. The qualitative differences in these patterns are more apparent than the quantitative ones in both cessation and commencement of movement.
Other dental treatment needs in patients who requested removable partial dentures
Authors: ISA Z. , YUSOF Z.
Published: June 2007

The aims of this study were to determine the dental and periodontal status and the associated treatment needs, other than that for prosthetic care, in patients who requested removable partial dentures. Forty‐six patients who had never worn removable partial dentures before were examined for plaque index, tooth status, gingival index, loss of periodontal attachment and tooth mobility. Prior to prosthetic treatment, 15% of the teeth needed conservative treatment and 1% needed extractions. From the periodontal point of view, 65% of the teeth needed some form of related therapy, and 2% of the teeth were at risk of extraction due to advanced mobility.