bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pathologic attrition and maximal bite force
Authors: DAHL B. L. , FLØYSTRAND F. , KARLSEN K. 
Published: June 2007

SummaryThe maximal bite force was recorded between antagonizing anterior teeth in a group (n= 10) of patients with pathologic attrition and in a control group. No statistically significant difference between the maximal bite forces was recorded. Also, the effect on the maximal bite force of the continuous wearing of a partial bite raising splint for 4 months was recorded.The great individuality in reaction patterns prohibited simple generalizations.However, in some individuals the maximal bite force was larger when biting on the splint than without, both at base line and after 4 months. Also, the maximal bite force showed a tendency to increase with time.The findings indicate that pathologic attrition is not necessarily associated with a high maximal bite force. Also, the maximal bite force recorded under various conditions is seemingly not an absolute value but rather the result of a number of factors of varying importance for different individuals.
Papillarity of the palatal mucosa
Authors: THOMAS C. J. , KOTZE T. J. V. W. , NASH J. M. 
Published: June 2007

SummaryA sample of 575 palatal casts was studied and found to possess varying degrees of papillary convolutions between and around the palatal rugae. No palatal appliances were worn and no irritative influence was present. A classification of 1–4 was established and the peak incidence was Class II at 48.4% (Class I, being an absence of papillarity, was 7.3%). It is postulated that the presence of a denture may well cause an inflammatory papillary hyperplasia to arise not by a progression through the various stages of denture stomatitis but directly, in an individual with a papillary palate.
The effect of acrylic bite plane splints and their vertical dimension on jaw muscle silent period in healthy young adults
Authors: FINGER M. , STOHLER C. S. , ASH M. M. 
Published: June 2007

SummaryA significant question relative to treatment and disappearance of symptoms is raising the bite in combination with a maxillary bite plane splint in patients with TMJ muscle dysfunction. The objective of this research was to investigate the effect, if any, occlusal bite plane splints have on the latency and duration of the menton tap silent period and particularly whether the degree to which the bite is raised is of significance. Recordings were made in healthy young adults from both anterior temporal and masseteric muscles while subjects were clenching at their 70% maximum clenching effort. Placement of a splint significantly (P>0·05) prolonged the silent period duration (SPD). However, mean SPD values taken at two different vertical raised bites did not differ significantly (P>0·05). The anterior temporal muscle SPD was less sensitive to a smaller change of vertical dimension than the masseteric SPD. Silent period latencies remained unchanged in all experimental conditions.
Is food particle size a criterion for the initiation of swallowing?
Authors: LUCAS P. W. , LUKE D. A. 
Published: June 2007

SummaryA small study on fifteen subjects found that brazil nut particles always broke down much more rapidly per chew than raw carrot particles. Both foods were swallowed, on average, after similar numbers of chews. However, a relationship was found which suggested that subjects that swallowed after few chews took less for carrots than brazils and vice versa for those that took more chews. An extended study with carrot showed a significant correlation between the rate of size breakdown and the number of chews required for swallowing in dentate subjects (r=0.69) but not in full denture wearers. The whole sample (n=79 including six wearers of partial dentures) gave a significant correlation of r=0.65. It is concluded that some consideration of the physical properties (texture) of foods is necessary before results from this type of study can be interpreted as relevant or not for dentistry.
The use of bilateral EMG equalization training in the treatment of temporomandibular joint dysfunction—A case report
Authors: KLONOFF E. A. , JANATA J. W. 
Published: June 2007

SummaryThis paper describes a single‐subject experiment testing two methods of using EMG biofeedback in the treatment of TMJ dysfunction. Following a baseline period, electrodes were placed on the left and right masseter muscles, and the subject was taught general relaxation of this area using visual biofeedback. Although data supported the conclusion that the subject had indeed learned to relax, this was not associated with any change in the report of pain or dysfunction. Equalization training, the goal being to equalize the levels of EMG in the right and left masseter muscles, was then begun. Once the patient had learned to maintain equal levels of EMG, relaxation was then re‐introduced. This produced substantial decreases in her reported pain, both within the session and averaged across days for the time between sessions. These treatment gains were maintained at 2‐month follow‐up.
Clinical and radiographic observations after 6 years on bridge abutment teeth carrying pinledge retainers
Authors: GUSTAVSEN F. , SILNESS J. 
Published: June 2007

SummaryA group consisting of 108 bridge recipients (71 female, 37 male) with a total of 114 bridges retained solely (n=40) by pinledges or retained by a combination (n=74) of pinledges and complete crowns was examined clinically and radio‐graphically 6 years after completion. The study was to review evidence of any displacement of bridges as well as the incidence of periapical changes and carious‐lesions of those abutment teeth fitted with pinledges (n=210). The results showed that bridges retained solely by pinledges had become displaced more frequently than bridges retained by a combination of crowns. The failure rates (%/year) for bridges retained solely by pinledges was 2.5% and for bridges with a combination of retainers 0.25%. Three teeth (1.4%) experienced pulp exposure during the preparatory work and 6 teeth (2.8%) had been or had to be rootfilled after 6 years. Carious lesions had developed in 6 abutments (1.9%).
Changes in jaw relations and activity of masticatory muscles in patients with immediate complete upper dentures
Authors: TALLGREN A. , TRYDE G. , MIZUTANI H. 
Published: June 2007

SummaryA longitudinal radiographic cephalometric and electromyographic investigation was performed on eighteen subjects provided with an immediate complete upper and a partial lower denture. The observation stages were: before final extractions and 7 weeks, 6 months and 1 year after denture insertion. The cephalometric analysis was based on measurements from lateral head films taken in centric occlusion. The EMG activity of the anterior temporal and masseter muscles was studied in postural position, light tapping and in maximal clench.The changes in jaw and occlusal relationships due to resorption of the edentulous maxillary ridge were slight, the mean decrease in occlusal vertical dimension during one year being 0.7 mm. The EMG clench activity at the pre‐extraction stage, when the patients occluded on a residual anterior dentition, showed low mean values round 100 μV, and a further decrease was observed at the post‐insertion stage. At the 1‐year stage all muscles displayed significant increases to above the post‐insertion level. The jaw muscle activity in light tapping and in postural position generally showed no significant mean changes during the observation period.The results indicate that preservation of a residual dentition in the lower jaw prevents marked changes in jaw and occlusal relationships and resulting changes in muscle activity.
A modified technique to determine the tear energy of impression materials
Authors: VRIJHOEF M. M. A. , LOURENS F. L. , LEYDEKKERS‐GOVERS G. F. M. 
Published: June 2007

SummaryA modified method to determine tear energy of impression materials is described. Trousers‐shaped specimens were prepared between two platens. They are different from those used before in that (1) a V‐shaped line is created so as to guide tear growth, and (2) the thickness gradually increases, then remains constant and, ultimately, decreases instantaneously. The specimens were tested at ten different rates between 0.2 and 50cm/min. λ can be computed from the force–time diagram. Six different materials were tested: two condensation silicones, Xantopren regular (Bayer, FRG) and Xantopren light; a polyvinylsiloxane, Reprosil regular (DeTrey, Switzerland); a polysulphide Coeflex regular (Coe, USA); a polyether, Impregum (Espe, FRG); and an alginate, Cavex, Fast Set, Dust Free (Keur & Sneltjes, The Netherlands). Tear strength (in kJ/m2) variations at rates between 0.2 and 50cm/min are as follows: Xantopren regular, 0.37–0.64; Xantopren light, 0.29–0.46; Coeflex, 1.10–5–29; Reprosil, 0.66–1.07; Impregum, 0.62–1.04; Cavex, 0.22–0.37. These values are consistent with those reported before. It might be concluded that the new test method gives reliable tear energy values.
Changes in physical and chemical properties of a dental palladium—silver alloy during metal—porcelain bonding
Authors: PAYAN J. , MOYA G. E. , MEYER J. M. , MOYA F. 
Published: June 2007

SummaryThe hardening ability of a dental palladium–silver (Pd–Ag–Sn–In) bonding alloy has been investigated, and the distribution of the elements along the metal–ceramic interface have been studied by microprobe analysis. The alloy was found to be highly heterogeneous in its ‘as‐cast’ condition, but homogenized alloy was obtained after heating the alloy at 1000°C for 2h. Hardening occurred after annealing at 650°C for 1 h. A longer thermal treatment caused the hardness to decrease (over‐ageing). The change in hardness could be attributed to an internal oxidation phenomenon. The additional elements tin and indium segregated towards the ceramic–metal interface, with a diffusion of indium only into the porcelain. Diffusion of silver in the ceramics, supposed to be the cause of the ‘greening’ of dental porcelains baked on silver‐rich alloys, has not been detected by the microprobe across the interface.
An examination of the surface corrosion state of dental fillings and constructions
Authors: YONTCHEV E. , HÅKANSSON B. , HEDEGÅRD B. , VANNERBERG N.‐G. 
Published: June 2007

SummaryA group of 115 patients with orofacial complaints has been examined. A new method for intraoral measurement of electrode potentials on the surface of the amalgam fillings and prosthetic constructions has been developed and applied. The possible connections between the measured electrode potentials and patients' saliva properties and their complaints have been discussed. No correlations between measured electrode potentials of the metallic fillings and constructions and important saliva properties could be found. No connections between the measured electrode potentials and the patients' complaints could be proved.
The instantaneous centre of rotation of a fixed unilateral distal extension partial denture
Authors: FEINGOLD G. M. , GRANT A. A. , JOHNSON W. 
Published: June 2007

SummaryA photographic technique was used to determine the instantaneous centre of rotation of a fixed unilateral distal extension partial denture and the teeth to which it was attached. The teeth involved were the lower canine and first premolar. When the two crowns were splinted together to provide support, both vertical and lateral saddle movement was reduced. Saddle support using only the first premolar produced a centre of rotation in the sagittal plane below the canine crown—which became located anterior to the canine when the two supporting teeth were splinted together. In the coronal plane, canine support produced an axis of rotation buccal to, and outside the confines of, the model; splinting of the canine and first premolar caused the centre of rotation in this plane to be located buccally and superior to the abutment tooth roots. The more posteriorly the saddle was loaded, the greater was the magnitude of the resultant movement.
Physical properties of periodontal dressing materials
Authors: RUBINOFF C. H. , GREENER E. H. , ROBINSON P. J. 
Published: June 2007

SummaryThe purpose of this study was to develop standardized reproducible testing methods for evaluating physical properties of periodontal dressing materials. Three commercial compositions (Coe‐Pak, Coe‐Pak Hard & Fast Set and WondrPak) were studied.Working and setting times were determined by observing the continuous changes in viscosity via the oscillating rheometer. The 24‐h and 1‐week tensile and shear adhesive bonds to enamel were studied by luting orthodontic lingual cleats with a standard film thickness to the orientated labial surfaces of extracted incisors and pulling them to failure. Dimensional change was studied over a period of 24h using a linear variable differential transformer (LVDT).The developed testing modalities have greater precision than those previously reported. The concept of ‘bench time’ was developed during which certain materials cannot be handled immediately after mixing.
The fracture toughness of repaired composite
Authors: DHURU V. B. , LLOYD C. H. 
Published: June 2007

SummaryThe fracture toughness (K′IC) at the interface formed between a composite substrate and more recently placed composite has been measured to determine the strength of the repair. The substrate material was 24 h old at the time of the repair and the fracture toughness of the repair was measured 24 h later. Five composite products were selected for repair by using either that particular product or one of the others. Repairs were made to clean fractured surfaces, and these after contamination with artificial saliva. The fracture toughness factor of any repair was significantly less than that for the respective control. The effect of surface contamination proved highly significant and reduced the fracture toughness. An interaction existed between adherend (substrate) and adhesive (addition) materials. Compatibility between these for matrix and initiation chemistries did not appear to be significant.
Safety and antibacterial properties of controlled release SnF2
Authors: TINANOFF N. , SIEGRIST B. , LANG N. P. 
Published: June 2007

SummaryTwo clinical studies were performed to evaluate the safety and efficacy of an intracoronal device for the controlled release of SnF2. SnF2‐polycarboxylate cement, containing approximately 72mgF−, was placed in subjects' molars requiring two‐surface restorations.In the trial for safety, eight subjects had the restoration in place for 34 days. The salivary fluoride levels were elevated to a mean of 0.3/106. over the experimental period. Urinary fluoride levels were only above baseline levels during the first few days. The restoration's physical properties were adequate; however, subjects experienced gingival irritation in areas where the restoration was contacted with gingiva.In the trial for efficacy, fourteen subjects had either a SnF2‐polycarboxylate or a placebo restoration placed in a molar tooth during a 2 week period of no oral hygiene. During the experimental period, the control subjects had higher levels of salivary total CFU, Streptococcus sanguis and Streptococcus mutans: while the subjects with the SnF2 restoration had increased S. sanguis and decreased S. mutans levels. No differences in G.I. or PL 1 scores were noted between groups.Further development of this controlled release system should include using the SnF2‐polycarboxylate restoration in more than one tooth per subject to increase the fluoride reservoir, and not allowing the restoration to contact gingival tissues.
An investigation into the compatibility of some irreversible hydrocolloid impression materials and dental gypsum products
Authors: OWEN C. P. 
Published: June 2007

SummarySome alginate impression materials produce rough, chalky, soft surfaces on gypsum casts. This is recognized by various standards, which include tests for an alginate's compatibility with gypsum, and its capacity to record details and impart these to a gypsum cast. These qualities were looked at in this study.The method used closely followed that laid down by International Standard ISO 1563–1978(E) for alginate impression materials. Ten alginates and seven gypsum products were tested. Using the criteria specified by this Standard, it was found that none of the materials tested was able to record the finest (0.020 mm) line on the test block. However, two elastomeric impression materials tested in the same manner also failed to reproduce this line, as did all the gypsum products when tested directly against the block. These findings cast some doubt on the efficacy of utilising such a fine line in the classification of these materials.Only thirty‐four of the seventy possible combinations were able to reproduce the 0.050 mm line. Eight combinations reproduced the 0.075 mm line as the finest line, and the remainder (thirty‐eight) failed to record any of the lines.Some of the alginate materials were treated with fixing solutions of varying concentrations of potassium sulphate and alum. The results obtained varied, sometimes producing marked improvement, sometimes deterioration in the surface quality of the subsequent gypsum casts, despite the fact that none of the manufacturers of the alginates recommended the use of fixing solutions.
A clinical report on the use of glass ionomer cement to restore cervical margin lesions
Authors: KNIBBS P. J. 
Published: June 2007

SummaryA glass ionomer cement of the powder/water type was used to restore cervical margin lesions. One hundred and fortv‐two restorations were reviewed over a period of 2.5 years.The material performed well clinically. The appearance of the restorations was good. Surface wear was noticed as time progressed. Nine restorations failed during the study. Failure of restorations was probably due to faults in clinical technique.
Cantilever bridges or removable partial dentures in geriatric patients: a two‐year study
Authors: BUDTZ‐JØRGENSEN E. , ISIDOR F. 
Published: June 2007

SummaryThe purpose of this study was to compare prosthetic, functional and occlusal conditions in twenty‐seven patients treated with distally extending cantilever bridges and twenty‐six patients treated with removable partial dentures (RPD) in the mandible. All patients had a complete upper denture. Mean age of the patients in both groups was about 69 years. The patients were under a supervised oral hygiene care throughout the 2‐year study period. There were 6.9±l.7 mandibular teeth left in the bridge group and 7.5±l.7 in the RPD group and the mean number of posterior teeth (natural teeth/denture teeth/pontics) in occlusion was 4.l±l.l and 7.3±l.4, respectively. During the study period signs and symptoms of mandibular dysfunction became significantly aggravated in the RPD group, P<0.05. A balanced occlusion in the muscular contact position was observed in 90% of the patients in the bridge group and in 76% of the RPD wearers. During the study period the need for dental or prosthetic treatment was negligible in the patients treated with bridges. In the RPD group, twenty‐two teeth were restored with fillings due to caries and in eight patients major adjustments of the sublingual bar were necessary due to irritation of the oral mucosa. This study has shown that treatment with distally extending cantilever bridges in the mandible is a favourable alternative to treatment with removable partial dentures in elderly patients with a reduced dentition.
The effect of function and rest on the amplitude of the TMJ click
Authors: MESSENGER K. L. , BARGHI N. 
Published: June 2007

SummaryIt has been suggested that simple resting and therapeutic exercises may be beneficial in reducing or eliminating clicking on the TMJ during mandibular movements. In the reported experiments the effects of short periods of exercise and rest on the amplitude of the TMJ clicking in non‐dysfunction subjects was recorded and compared. This preliminary study suggests that the TMJ clicking sound is affected unpredictably under different imposed conditions.
Masticatory muscle activity as a function of parafunctional, active and passive oral behavioural patterns
Authors: MOSS R. A. , VILLAROSA G. A. , COOLEY J. E. , LOMBARDO T. W. 
Published: June 2007

SummaryOral behavioural patterns have received limited empirical support for their causal role in the development of head and facial pain. The present study was designed to assess electromyographic (EMG) variations in six muscle groups (i.e., bilateral masseter, temporalis and orbicularis oris) as a function of various oral behavioural patterns. A second purpose was to determine whether mandibular movement patterns and specific oral behaviours could be predicted by EMG patterns. Eleven non‐pain subjects followed each of twenty oral behavioural patterns while EMG was recorded. Electromyographic change scores were computed for each behaviour relative to baseline measures. Initial analyses were performed using factorial repeated measures ANOVAS. Using post hoc analyses as general guides, specific EMG criteria were developed for classifying mandibular movements. For most subjects, EMG patterns accurately classified teeth clenching, protrusive/retrusive movements, right movements, left movements and lip movement patterns. Wide individual variations were found among muscle groups for identical behaviours. The association between particular oral behaviours and EMG patterns may explain ‘sinus’ headaches and certain types of facial pain.
Treatment times for adhesive bridges
Authors: CREUGERS N. H. J. , van't HOF M. A. 
Published: June 2007

SummaryThe aim of this study was to collect information about the mean working time needed to accomplish the clinical procedures in applying an adhesive bridge, and to gain an insight into the factors that influence the working time. The study was carried out as part of a clinical trial. One hundred and fifty‐one patients needing one adhesive bridge were selected for this study and divided between five operators. Clinical procedures were carried out following a written protocol. The statistical method consisted of an ANOVA after log‐transformation of the working times. The total mean working time needed to accomplish the clinical procedures for adhesive bridges was 60·7 min (s.d.±16·5 min). The mean working time increased by 30% where the abutment teeth were restored with class II or class III restorations. No influence was found related to: (1) type of bridge (i.e. macromechanical versus micromechanical), (2) type of luting resin and (3) location of the bridge. A significant effect on the working times was found for: (1) operator, (2) tooth preparation and (3) occlusal adjustments. With increasing experience of the operator the median working time decreased by up to 35%. The data from this study are considered as useful basic information for efficient planning in the dental practice and for a further cost‐benefit analysis.
Stress as a factor in muscle and temporomandibular joint pain
Authors: LUNDEEN T. F. , STURDEVANT J. R. , GEORGE J. M. 
Published: June 2007

SummaryStress‐induced muscle hyperactivity has been proposed as a major aetiological factor in the production of pain in the muscles of mastication and the temporomandibular joints. In the present study, a total of fifty‐two patients with joint or muscle pain were evaluated for stress with the Derogatis Stress Profile (DSP). The muscle pain group (n=24) had higher clinician ratings of psychological factors, stress and chronicity. The muscle‐pain group also had higher Environmental Stress scores on the DSP, more intense pain, and more activity impairment than the joint‐pain group (n=28). The results of multiple regression analysis suggest an association between pain, depression, and impairment of activity in the muscle‐pain group but not in the joint‐pain group. The overall results further suggest that muscle pain develops at ‘normal’ levels of stress.