bluuebunny/crossref_metadata_2025 huggingface dataset:
Permeability of dentine after Nd:YAG laser treatment: an in vitro study
Authors: SCHALLER H.‐G. , WEIHING T. , STRUB J.R.
Published: August 2010

summary
The purpose of this investigation was to determine the effects of Nd:YAG laser treatment on the permeability of dentine. Forty dentine discs were prepared by horizontal sectioning through the middle coronal third of freshly extracted non‐carious third molars. After the removal of the pulp the discs were finished with 600 grit and divided into three test groups and one control group (n = 10). For the test groups three different laser power settings were chosen: test group A: 3 × 60 sec, 60 mJ; test group B: 3 × 60 sec, 90 mJ; test group C: 3 × 60 sec, 120 mJ. No laser treatment was performed on the control group. In a two‐chamber system the filtration rate of dentine tubules from an exactly defined area of the specimens was measured using a radioactive Ringer solution under a pressure of 30 cm H2O. Permeability measurements were carried out three times prior to lasing, three times immediately following laser treatment and six times after the application of phosphoric acid. Analysis of variance showed a significant influence of the Nd:YAG laser treatment on the permeability of dentine (P < 0.001). The mean quotient of non‐treated control vs. lased dentine was 2.19 ± 0.86 for the 60 mJ beam, 1.49 ± 0.88 for the 90 mJ beam, and 204 ± 2.17 for the 120 mJ beam. Etching the lased surfaces had a statistically significant influence on the permeability of the dentine only in the 60 mJ group (P < 0.001). The data show that the Nd:YAG laser treatment often increases the permeability of smear layer covered dentine but moderates the increase of permeability after etching the surface with phosphoric acid.
The optimum curing cycle for a light‐ and heat‐cured composite inlay material
Authors: RAZAK A.A.A. , HARRISON A.
Published: August 2010

summary
The transverse bend test and surface microhardness test were used to determine the optimum curing cycle for a light‐ and heat‐cured composite inlay material. Specimens were light‐cured (control) and light‐ and heat‐cured using the following temperatures: 50°C for 5 min; 50°C for 10 min; 100°C for 1 min; 100°C for 5 min; 100°C for 10 min; and l00°C for 15 min. Heat‐curing in boiling water at 100°C for at least 1 min significantly improved the transverse strength, modulus of elasticity and surface microhardness compared to light‐curing only or at 50°C. The curing cycle of 100°C for 5 min is considered the most appropriate.
Analysis of two methods for occlusal contact registration with the T‐Scan system
Authors: CARTAGENA A. GARCIA , SEQUEROS O.GONZALEZ , GARCIA V. C. GARRIDO
Published: August 2010

summary
Various authors have studied the reprodcibility of occlusal contact by means of the T‐Scan computerized system and obtained contradictory results. In the present work the valve of the T‐Scan system as a method for exploring occlusion has been analysed. For this purpose, the same variable, i.e. the number of contacts, was recorded in 31 subjects using the two operation modes enabled by the T‐Scan and the respective results were then compared. After an analysis of variance was performed to test the equality of averages of the number of tooth contacts for each patient in the four positions studied (maximum intercuspation, edge to edge protrusion, right laterality and left laterality) in the time and force analysis modes, the results obtained showed that the number of occlusal contacts is significantly different for each patient both in the various mandibular positions and in the force and time analysis modes, being proportionally greater in the latter case.
Trial of duplication procedure for complete dentures by CAD/CAM
Authors: KAWAHATA N. , ONO H. , NISHI Y. , HAMANO T. , NAGAOKA E.
Published: August 2010

summary
The purpose of this study was to duplicate the shapes of complete dentures by using a computer‐aided design/manufacturing (CAD/CAM) system. The shapes of the complete dentures of an edentulous patient were measured using a non‐contact type shape measurement system and morphological data at the interval of 0.25 mm were obtained in the X‐axis and Y‐axis directions. Measurement was performed from the occlusal surface and mucosal surface sides. Based on the three‐dimensional morphological data, cutter paths for cutting were generated. For cutting, the three‐step method consisting of rough cutting, finish cutting, and partial finish cutting was used and for duplicating the dentures the modelling wax was cut using a computerized numerical control (CNC) processor and ball‐end mills with diameters of 6 mm and I mm. The method for the controlling of three axes (X, Y, and Z) of CNC machine was used, and cutting was performed only from two directions. Although further improvements are needed in the measurement and cutting in acute slope areas, the duplication of complete dentures appears to be possible using the CAD/CAM system.
A multiparametric analysis of occlusal and periodontal jaw reflex characteristics in young adults with normal occlusion
Authors: SUDA S. , MATSUGISHI K. , SEKI Y. , SAKURAI K. , SUZUKI T. , MORITA S. , HANADA K. , HARA K.
Published: August 2010

summary
Periodontal jaw reflex, duration of percussion sounds, tooth mobility, and time‐moment analysis of occlusal contacts by the T‐scan system was recorded in nine periodontally healthy volunteers. The results showed that (i) reflex responses to the pressure applied to the uppercentageral incisors in the lingolabial direction varied, depending on the background jaw‐clenching force (BCF) of the same‐sided first molars. The BCF levels to elicit excitatory reflexes were 6–8Kgf, and inhibitory reflexes were clearly elicited with a BCF of l0Kgf and beyond. (ii) Duration of percussion sounds via an occlusal sound analyser (4.73–4.84mS: upper first molars. 4.89–5.00mS: uppercentageral incisors) and tooth mobility using a ‘Periotest’ (3.3–3.5: upper first molars, 5.5–5.6: uppercentageral incisors) showed a normal value. (iii) The time moments of occlusal contacts were symmetrical toward the midsagittal axis of the occlusal plane. The centre of the anterioposteriol occlusal contacts was located in the first molar regions.
Clinical evaluation of cervical dentine sensitivity in a population of patients referred to a specialist periodontology department: a pilot study
Authors: CHABANSKI M.B. , GILLAM D.G. , BULMAN J.S. , NEWMAN H.N.
Published: August 2010

summary
The prevalence of tooth sensitivity [Cervical Dentine Sensitivity (CDS)] in adult populations indicates that 8–35% of subjects reported CDS depending on the population studied and the methodology used. Few studies, however, have reported on the prevalence of CDS in periodontal patients. The aim of the study was to determine the prevalence, severity and distribution of CDS in patients referred for specialist periodontal diagnosis. Fifty‐one patients [27 male, 24 female; mean age 48.5 years (standard deviation 11.63)] who gave their informed written consent were clinically evaluated for CDS using recognized methods of assessment, namely Yeaple® probe, cold air blast and subjective evaluation. Other clinical variables (e.g. plaque and recession scores) were also recorded at this visit. Regression analysis and correlation coefficients were used to determine the relationship between the clinical variables. The results demonstrated a prevalence of CDS ranging between 72.5 and 98% of patients, with no significant gender difference. Results for the distribution of tooth types showed that molar teeth were mainly affected, followed by left canines and premolars. No correlation was noted between plaque, recession, response to tactile or thermal stimulation. Pain response from tactile and thermal stimulation showed no significant difference between tooth surfaces. Cold stimulation was perceived to be the dominant pain‐producing stimulus as had been previously reported. The results of this investigation support those from another study, which found the prevalence of CDS to be higher in periodontal patients than has been reported elsewhere. This finding would suggest that previous periodontal treatment and/or periodontal disease may play a role in the aetiology of CDS.
An optical system for measuring inclination and area of occlusal facets
Authors: HIBI H. , AI M.
Published: August 2010

summary
Occlusal facets are regarded as an individual record of occlusal contacts that result from various mandibular movements. Analysing characteristics of the facets is important for the functional assessment of the stomatognathic system. A new system which quantifies such characteristics optically has been developed. This system is composed of optical devices, a graphic image‐processor, a set of stages for mounting and positioning the model and laser indicators of the measuring point. The system enables the inclination and area of each facet and its location to be measured and its processed image displayed on the graphic monitor.
Electromyographic activity in patients with temporomandibular disorders
Authors: Pinho J. C. , Caldas F. M. , Mora M. J. , Santana‐PenÍn U.
Published: August 2010

Evaluation of masticatory muscle activity by surface electromyography (EMG) is a valuable tool for diagnosing dysfunction of the masticatory apparatus. However, controversy exists with regard to the usefulness of the EMG for patients with temporomandibular disorders (TMD). Forty patients with TMD were subjected to surface EMG of the masticatory muscles. These patients had consulted because of temporomandibular pain and clicks. In most cases (75%), the symptoms affected the patient's left side. Overall mean resting activity was 2·52 μV±1·25 μV (s.d.), which is slightly higher than in comparable healthy subjects (1·92±1·20 μV). Mean resting activity was highest in the anterior digastric muscle (3·49 μV) on the left side. Overall mean activity during clenching was 66·77±35·22 μV, which is about half that observed in healthy subjects (110·30±82·97 μV). During leftward movement of the jaw, activity was on average highest in the left digastric, while during rightward movement, activity was on average highest in the right anterior temporal (AT). Our results thus indicate that patients with temporomandibular joint (TMJ) disorder show: (1) a slight increase in basal tone; (2) a significantly reduced capacity for clenching; and (3) an apparently paradoxical inhibition of the dysfunctional‐side AT during movement of the mandible towards that side.
Influence of silanization and filler fraction on aged dental composites
Authors: Lin C.‐T. , Lee S.‐Y. , Keh E.‐S. , Dong D.‐R. , Huang H.‐M. , Shih Y.‐H.
Published: August 2010

The effect of silanization and filler fraction on the mechnical properties of aged dental composites was investigated. Experimental composites (75/25 Bis‐GMA/TEGDMA resin reinforced with 0, 12·6, 30·0, and 56·5 vol% 8 μm silanized/unsilanized BaSiO6) were fabricated into 4·7 mm diameter×2·2 mm thick discs and 3·5 mm diameter×7·3 mm thick discs for diametral tensile and compressive tests, respectively. The effect of immersion in 75% ethanol at 37 °C for 0–30 days on the diametral tensile strength (DTS) and compressive strength (CS) of the samples was evaluated and analysed by anova and Tukey LSD test. The fracture interface between filler and resin matrix was then examined by scanning electron microscope. Results and subsequent statistical evidence from DTS (18·6±7·6 MPa, silanized versus 11·7±2·6 MPa, unsilanized) and CS (85·1±29·7 MPa, silanized versus 56·0±11·3 MPa, unsilanized) strongly implies that silanization may greatly enhance the mechanical properties of the resin composites. Furthermore, it also shows that both DTS and CS increased proportionally as the filler fraction of the composites increased. However, in the unsilanized groups, DTS decreased (up to 40%) as the filler fraction increased, and CS showed no relevance to the filler fraction at all. As for the influence of aging, it was found that both DTS and CS showed a significant decrease after immersion in 75% ethanol, and silanization heavily correlated with the filler fraction of aged‐resin composites. Microscopic examination of the fractured samples showed that failure primarily occurred within the resin matrix per se for silanized composites and adjacent to the filler particles for unsilanized composites. All the evidence points to the conclusion that mechanical properties of aged‐resin composites can be greatly influenced by silanization and the filler fraction.
An in vitro assessment of the strength of porcelain veneers dependent on tooth preparation
Authors: Hahn P. , Gustav M. , Hellwig E.
Published: August 2010

The treatment of teeth using veneer restorations combines aesthetic and functional improvements with a low destructive technique. Different kinds of tooth preparation techniques are described in the literature for this kind of restoration. This in vitro study aimed to examine the influence of the incisal preparation on the loadability of teeth restored with porcelain laminate veneers. Thirty‐six selected mandibular incisors were randomly assigned to three groups with 12 teeth per group. In the first group, only the facial surface was prepared. In the second group, the preparation included a rounded incisal edge and a distinct chamfer lingually. The third group served as an unprepared control. Empress® veneers were then fabricated and cemented with a low viscous luting composite material. After 120 days storage in Ringer's solution, the specimens were loaded incisally to the point of failure. Statistical analysis of the results showed significant differences between the series (P=0·0103). Group 2 (with preparation of the incisal edge) exhibited the lowest fracture resistance (466±99 N) (N, mean forces). When prepared only facially, the teeth restored with Empress® veneers reached the strength of unprepared teeth. Compared with the biting force described for incisors in the literature, the in vitro loadability reached in this investigation seems to jusitify the clinical use of both preparation designs tested.
Propagation of the impact on the tooth caused by jaw tapping movement
Authors: Kanaoka R. , Suenaga H. , Fujii H.
Published: August 2010

The influence of mechanical stimulation on the human body is extremely important. We hypothesized that if tooth impact is propagated to other sites of the body, this impact will have some effect on those sites as well. The purpose of this study was to investigate the extent to which tooth impact was propagated in the head and neck. It was found that the waves recorded on the upper canine are divided into a high frequency component and a low frequency component at a border of approximately 7 kHz. The amplitude of the impulse wave was 80·813 g for the low frequency component, and 177·839 g for the high frequency component. In terms of propagated vibration from the canine, the amplitude of the low frequency component was larger than that of the high frequency component, and greatest at the chin, followed in descending order by the zygomatic bone, forehead and vertebra prominens. For both frequency components, the amplitude of the propagated vibrations was small compared with the impulse waves. These results provide a basis for future analysis of the influence of such impact on cell response.
Adaptation of acrylic dentures reinforced with metal wire
Authors: Teraoka F. , Nakagawa M. , Takahashi J.
Published: August 2010

The aim of this study was to reveal the effect of metal wire on the adaptation of the denture reinforced with it. Forty maxillary dentures were made with two polymerization systems (DS system and SR‐Ivocap system). The dentures were divided into two groups: (1) the unreinforced dentures (control) and (2) the dentures reinforced with metal wire 1·0 mm in diameter. Discrepancies between the denture base and the stone cast were measured at five points immediately after polymerization and after a 30‐day immersion in water. The data were analysed using a two‐way or one‐way ANOVA test. Dentures reinforced with metal wire exhibited significantly lower adaptation to the stone cast than the unreinforced ones for each polymerization system. Immersion in water did not affect the adaptation of dentures reinforced with metal wire for each polymerization. Unreinforced dentures made by the DS system had significantly smaller discrepancies compared with the dentures processed with the SR‐Ivocap system. The adaptation of the dentures reinforced with metal wire decreased in comparison with the unreinforced ones regardless of the polymerization method. This should be considered when metal wire is used clinically as reinforcement.
Chemical degradation of composite restoratives
Authors: Yap A. U. J. , Tan S. H. L. , Wee S. S. C. , Lee C. W. , Lim E. L. C. , Zeng K. Y.
Published: August 2010

The chemical environment is one aspect of the oral environment, which could have an appreciable influence on the in vivo degradation of composite restoratives. The effects of chemical media on surface hardness of four composite restoratives (Silux [SX], Z100 [ZO], Ariston [AR] and Surefil [SF]) were investigated. The relationship between hardness and the thickness of the degradation layer was also studied. Thirty six specimens (3 × 4 × 2 mm) were made for each material. Following polymerization, the specimens were stored in artificial saliva at 37 °C for 24 h. The specimens were then randomly divided into six groups of six, subjected to microhardness testing (load = 500 gf, dwell time = 15 s) and stored in the following chemicals for 1 week at 37 °C: artificial saliva (S), distilled water (W), 0˙02 N citric acid (C), 0˙02 N lactic acid (L), heptane (H) and 75–25% ethanol–water solution (E). After conditioning, the specimens were again subjected to hardness testing and sectioned. Change in hardness (DH) was computed and the thickness of the degradation layer (DL) was measured using a computerized image analysis system at 600× magnification. Results of statistical analysis (ANOVA/Scheffe’s [P < 0˙05]) of DH based on materials were as follows: SX – E > all other mediums; ZO – W > C; and AR – S, W, E > H (> indicates significantly greater hardness change). No significant difference in DH was observed between the different chemicals for SF. The effects of chemical media on DH were found to be material dependent. A significant but weak positive correlation (Pearson’s correlation [P < 0˙05]) exists between change in hardness and thickness of the degradation layer.
Diagnostic targeting of temporomandibular disorders
Authors: Shifman A. , Gross M.D.
Published: August 2010

This article describes a diagnostic chart that is organized for a versatile representation of various conditions of temporomandibular disorders (TMD). It facilitates the grading of disorder severity and visualization of probable mutual effects between groups of disorders. It also enhances the clinician’s awareness of potential systemic involvement in TMD by incorporating it into the chart. Comparison of charts completed at consecutive examinations is helpful for the assessment of disorder progression, regression or for the refining of diagnoses.
Handling characteristics of a palladium‐free gallium‐based alloy compared with a high copper dental amalgam in a simulated clinical trial
Authors: Shaini F. J. , Shortall A. C. C. , Ellakwa A. E. , Marquis P. M.
Published: August 2010

The aim of the current study was to compare the handling characteristics of a palladium‐free gallium‐based alloys (Galloy®) with those of a high‐copper amalgam (Permite C®). The study had a particular interest in the evaluation of the direct placement delivery system used with both alloys. Ten dentists participated in the current study. Each placed two amalgam and two gallium‐based alloy restorations in conventional class II cavities prepared in acrylic typodont teeth. None of the participating dentists had used the direct placement delivery system or had any previous experience with gallium‐based alloy and no practice was allowed beforehand. The restorations were evaluated according to the following criteria: ease of loading the cavity (delivery system), ease of condensation, capacity to produce and sustain contact area, ease of carving, resistance to damage during removal of the matrix band, overall quality of the restoration and the available working time. Each criterion was given a score on a scale of 1–5 (1: very poor, 2: poor, 3: fair, 4: good, 5: very good). The results showed no statistically significant difference in the evaluated criteria between the two alloys (P > 0˙05) except for criterion number 2 (ease of condensation, P=0˙0005).
Comparison of photo‐activation versus chemical or dual‐curing of resin‐based luting cements regarding flexural strength, modulus and surface hardness
Authors: Hofmann N. , Papsthart G. , Hugo B. , Klaiber B.
Published: August 2010

This study investigated the efficiency of chemical activation of dual‐cure resin‐based luting cements as compared with light‐ and dual‐curing. Curing was performed by (i) mixing base and catalyst without subsequent irradiation (chemical curing=CC), (ii) mixing base and catalyst with direct irradiation (dual‐cure=DC) or with (iii) irradiation through 2·5 mm of leucite‐reinforced glass–ceramics (IPS Empress, Ivoclar) (dual‐cure through porcelain=DCtP), (iv) using only the base paste with direct irradiation (light‐curing=LC) or with (v) irradiation through porcelain (light‐curing through porcelain=LCtP). Specimens of four fine‐hybrid DC resin composites and one self‐cure hybrid resin composite (only CC) were prepared and tested after 24 h for flexural strength, modulus of elasticity (ISO 4049) and surface hardness (Vickers). For all materials and parameters, dual‐curing produced higher values than LC, even when irradiation was performed through porcelain. Following self‐curing without photo‐activation, flexural strength was 68˙9–85˙9%, the modulus 59˙2–94˙5% and Vickers hardness 86˙1–101˙4% of the corresponding values obtained by dual‐curing with direct irradiation. Light‐curing through porcelain as compared with direct irradiation reduced the values for most parameters and materials. In contrast, dual‐curing maintained flexural strength for all, the modulus for three and the hardness for one of the materials. The mechanical properties of the self‐curing resin cement ranged between those of the DC materials.
The effect of the gonial angle, ramus length, age and gender on the temporomandibular opening index
Authors: Moipolai P. , Karic V. V. , Miller V. J.
Published: August 2010

summary  Linear mouth opening is often used to assess the limitation of mandibular movement. However, this has a number of limitations. It is dependent on variables such as age, gender and ramus length. A new measure of movement has been developed previously, called the temporomandibular opening index (TOI). Forty‐two subjects who did not exhibit signs and symptoms of temporomandibular disorder (TMD) were recruited to this study. The relationship of age, gender, gonial angle, ramus length and the TOI was studied. Linear regression analysis showed that the TOI was not dependent on gender (P > 0·644), gonial angle (P > 0·327), ramus length (P > 0·248) and age (P > 0·690). The index may therefore be a better measure of mandibular movement.
Clinical evaluation of the marginal fit of cast crowns – validation of the silicone replica method
Authors: LAURENT M. , SCHEER P. , DEJOU J. , LABORDE G.
Published: August 2010

Summary  Replication of the space between a tooth and its cast crown, using a light‐body silicone supported by a heavy‐body silicone, is a recognized technique to evaluate the quality of a restoration. This study validates a similar method that is of great clinical and experimental interest. Whatever the type of silicone used, comparison is possible between different technical procedures of crown elaboration (type of impression, type of material, method of spacing, etc.). If an appropriate silicone is used, the cement space may be reproduced and its thickness measured, whatever the localization (cervical, axial, occlusal).
Passive fit of frameworks in titanium and palladium–silver alloy submitted the laser welding
Authors: DE SOUSA S. A. , DE ARRUDA NOBILO M. A. , HENRIQUES G. E. P. , MESQUITA M. F.
Published: August 2010

Summary  This study evaluated the precision of fit of implant frameworks cast in titanium (cp Ti) and palladium–silver alloy (Pd‐Ag), made by the one‐piece cast and laser welding techniques. From a metal matrix with five implants, 20 master casts were obtained, to which replicas of implants were incorporated. On these masters 10 frameworks were made for each type of material (cp Ti and Pd‐Ag alloy). Half of these were made by the one‐piece cast technique and the other half by the laser welding technique. The implant/prosthesis interface was analysed and measured in the vestibular and lingual regions of the central and distal implants with the help of a measuring microscope. The results indicated that in the central cylinders, the Tukey test (P < 0·0005) showed a significant difference in the passive fit between the laser‐welded frameworks (34·73 μm) and those one‐piece cast frameworks (151·39 μm), and as regards materials, the palladium–silver alloy (66·30 μm) showed better results than the titanium (119·83 μm). In the distal cylinders there was no significant difference between the frameworks cast in titanium and palladium–silver by the one‐piece technique. However, after laser welding, there was a significant difference for the frameworks cast in titanium (31·37 μm) and palladium–silver (106·59 μm).
In vitro comparison of the efficacy of CarisolvTM and conventional rotary instrument in caries removal
Authors: Yazici A. R. , Atílla P. , Özgünaltay G. , Müftüoglu S.
Published: August 2010

summary  The purpose of this in vitro study was to compare the efficacy of a new chemomechanical caries removal agent, CarisolvTM (MediTeam AB, Sävedalen, Sweden), with conventional slow‐speed rotary instrument (bur). Fourteen extracted human molar teeth with deep dentine caries and no enamel coverage were selected for the study. Their laser fluorescence values were over 30 (DIAGNOdent®; KaVo, Biberach, Germany). After the teeth were sectioned through the centre of the carious lesion, one half was removed with conventional drilling (bur); the other half was removed with Carisolv gel. Removal of carious dentine was continued until the lesion was deemed caries‐free by visual and tactile criteria. The preparation time for each caries removal technique was also noted. The two halves of each tooth were fixed in 10% buffered‐formaldehyde for 1 week. They were then decalcified, dehydrated and embedded in paraffin blocks for histological studies. After taking serial sections of 5 μm thickness, sections were mounted on glass slides, deparaffinized, dehydrated and stained with toluidine blue for observation under a light microscope. Each section was examined for the presence of bacteria. Complete removal of caries was achieved in 13 (93%) of 14 conventionally prepared teeth, and 5 (36%) of 14 chemomechanically prepared teeth (P < 0·05). Mean (±SD) time for caries removal was 272 s (±53·3) with Carisolv, and 116 s (±49·4) with drilling. The results of this study suggest that conventional rotary instrument (bur) was more effective than Carisolv in removal of carious tissue and also takes shorter time.
Comparison of clinical and magnetic resonance imaging diagnoses in patients with TMD history
Authors: Üşümez S. , Öz F. , Güray E.
Published: August 2010

summary  The aim of this study was to evaluate the diagnostic accuracy of a well‐defined clinical examination for diagnosing anterior disc displacement with and without reduction. A series of 40 patients with temporomandibular disorder (TMD) history were examined according to well‐defined routine criteria. This examination included detailed history‐taking, standardized clinical head and neck examination that included measurements of the range of motion, palpation of the temporomandibular joints and muscles of mastication for pain and auscultation of joint sounds. Magnetic resonance images of the joints were used as ‘gold standard’. Diagnostic accuracy of the clinical examination was 83% for determining normal disc–condyle relationship, 72% for diagnosing anterior disc displacement with reduction, and 81% for diagnosing anterior disc displacement without reduction. Our results suggest that anterior displacement of the disc can be diagnosed with considerable accuracy using a well‐defined clinical examination only. Therefore, we conclude that not all patients with TMD symptoms require magnetic resonance imaging examination before treatment.
Denture‐related oral mucosal lesions in a Brazilian school of dentistry
Authors: Coelho C. M. P. , Sousa Y. T. C. S. , Daré A. M. Z.
Published: August 2010

summary  The purpose of this study was to survey the frequency of denture‐related lesions of the oral mucosa in patients treated at a Brazilian dental school and to determine if the oral lesions were related to age, sex, denture type, length of denture use and denture cleaning methods. The denture‐related lesions observed in this study were chronic atrophic candidiasis, chronic hyperplastic candidiasis, denture‐induced fibrous inflammatory hyperplasia (FIH), traumatic ulcer, angular cheilitis and flabby ridge. The most frequent lesion, chronic atrophic candidiasis, occurred more frequently in females, in complete maxillary denture wearers, with denture use for 16–20 years. The most common method of cleaning dentures was a toothbrush and toothpaste. These results suggest that dentures can cause a wide range of lesions of the oral mucosa, that could be prevented with follow‐up to evaluate dentures and provide instructions on how to maintain oral tissues healthy.
Time series analysis of jaw muscle contraction and tissue deformation during mastication in miniature pigs
Authors: Liu Z. J. , Green J. R. , Moore C. A. , Herring S. W.
Published: August 2010

summary Masticatory muscle contraction causes both jaw movement and tissue deformation during function. Natural chewing data from 25 adult miniature pigs were studied by means of time series analysis. The data set included simultaneous recordings of electromyography (EMG) from bilateral masseter (MA), zygomaticomandibularis (ZM) and lateral pterygoid muscles, bone surface strains from the left squamosal bone (SQ), condylar neck (CD) and mandibular corpus (MD), and linear deformation of the capsule of the jaw joint measured bilaterally using differential variable reluctance transducers. Pairwise comparisons were examined by calculating the cross‐correlation functions. Jaw‐adductor muscle activity of MA and ZM was found to be highly cross‐correlated with CD and SQ strains and weakly with MD strain. No muscle's activity was strongly linked to capsular deformation of the jaw joint, nor were bone strains and capsular deformation tightly linked. Homologous muscle pairs showed the greatest synchronization of signals, but the signals themselves were not significantly more correlated than those of non‐homologous muscle pairs. These results suggested that bone strains and capsular deformation are driven by different mechanical regimes. Muscle contraction and ensuing reaction forces are probably responsible for bone strains, whereas capsular deformation is more likely a product of movement.
IL‐17 and Regulatory Cytokines (IL‐10 and IL‐27) in L. braziliensis Infection
Authors: NOVOA R. , BACELLAR O. , NASCIMENTO M. , CARDOSO T. M. , RAMASAWMY R. , OLIVEIRA W. N. , SCHRIEFER A. , CARVALHO E. M.
Published: August 2010

Cutaneous leishmaniasis (CL) is characterized by high production of pro‐inflammatory cytokines and development of pathology. Individuals with subclinical L. braziliensis infection (SC) have a positive skin test to leishmania, but do not develop disease. We evaluated whether the downregulation of inflammatory response in SC is mediated by IL‐10 and IL‐27 and whether IL‐17 is associated with control of infection. Participants include SC individuals, patients with CL and healthy subjects. Cytokines protein and mRNA were detected by ELISA and real‐time PCR. IFN‐γ and TNF‐α levels were higher in CL than in SC group. The IL‐10 levels and mRNA for IL‐10 were similar in both SC and CL. mRNA for IL‐27 was increased in cells from SC after stimulation with L. braziliensis antigen. There was a tendency for increased levels of IL‐17 in SC compared to CL. The weak type 1 immune response observed in SC L. braziliensis infection is not because of the regulatory effects of IL‐10 and IL‐27. The control of Leishmania infection may be mediated by innate immune response with participation of IL‐17. The results from this pilot study warrant further larger studies to investigate the potential contributions of IL‐17 and IL‐27 to the control of L. braziliensis infection.
Binding of IgA to Protein‐A‐Containing Staphylococci: Relationship to Subclasses
Authors: SALTVEDT E. , HARBOE M.
Published: August 2010

Among 54 human monoclonal IgA proteins, 5 inhibited the binding of labeled human monoclonal IgM (IgM Se and IgM Ba) to protein‐A‐containing staphylococci, whereas 48 did not have this ability. One protein (IpA Ha) showed discordant findings in the IgM Se and IgM Ba inhibition assays. Among the 54 IgA proteins, 49 were of the IgA1 and 5 of the IgA2 subclass All of the 5 IgA2 proteins inhibited the binding of IgM Se and IgM Ba to staphylococci, whereas the 48 proteins that reacted negatively in the two inhibition belonged to the IgA1 subclass. These findings show that the ability to react with staphylococci is a properly of the IgA2 subclass. IgM proteins may also be divided into two groups based on different reactivities with protein A. It is proposed to call the two IgM subclasses IgM1 and IgM2, where the latter is defined by ability to react with protein A.
Estimation of Lymphocyte Subpopulations in the Peripheral Blood of Patients with Sarcoidosis
Authors: SØRENSEN S. F. , HARDT F. , VEIEN N. K.
Published: August 2010

Lymphocyte subpopulations in the peripheral blood of 36 sarcoidosis patients and 36 age‐ and sex‐matched controls were determined, using the sheep erythrocyte rosette (SRBC‐R) technique and immunofluorescence staining with whole rabbit anti‐human immunoglobulin antisera. In the patient group the total number of lymphocytes, SRBC‐R lymphocytes, and IgM‐positive lymphocytes was reduced in comparison to in the control group. In the patient group no correlation could be found between any of the lymphocyte subpopulations and disease stage, cutaneous involvement of the disease, or cutaneous reactivity to purified protein derivative and dinitrochlorobenzene.
A Simple Stained Protein Assay (SPA) for Rapid Total Protein Determination Applied to Spinal Fluids
Authors: WADSWORTH C.
Published: August 2010

A rapid, simple technique measures small amounts of total protein applied on an agarose gel slab. Alternating current through the gel may reduce diffusion of the protein, which is chemically fixed. The intensity of the Coomassie‐Blue‐stained spots is a function of the amount of protein determined by comparison with simultaneously run standards. Densitometric and visual estimates of protein in spinal fluids by the stained protein assay correlated with Lowry values highly significantly (n= 28; P < 0.001, Spearman test of rank correlation). As little as 0.2 μg protein was measured; this figure should be compared with 10 μg for the Lowry method. The reproducibility of the method was ± 5%.
Suppressor Cell Activity in a Male Infant with T‐ and B‐Lymphocyte Dysfunction Treated with Thymosin
Authors: HANSON L. Å. , LINDHOLM L. , CARLSSON B. , FASTH A. , FÄLLSTRØM S. P. , WADSWORTH C. , VÄRENDH G.
Published: August 2010

A male infant with bilateral iris coloboma who had had repeated infections and malabsorption was studied. The levels of total lymphocytes and of T Rod B cells were normal or high, but IgA became undetectable and IgG low, whereat IgM was normal. His lymphocytes did not respond to phytohemaggtutinin (PHA), concanavalin A. pokeweed mitogen (PWM) or in mixed lymphocyte reactions (MLR). nor did they respond in vitro when thymosin was included in the test systems, He was skin‐test‐negative, even to dinitrochlorobenzene. His crudely isolated T lymphocytes and the, supernatant of his PHA stimulated lymphocytes inhibited the response of normal lymphocytes to PHA, PWM, and in MLR. During thymosin treatment skin tests and lymphocyte reactivity tit mitogen remained negative. He became faintly positive in MLR, and the suppressor activity in the supernatant of his PUA‐stimulated lymphocytes DO longer inhibited the response of normal lymphocytes to PHA, PWM or in MLR In parallel with thymosin treatment he showed quite marked clinical improvement
Anti‐Parental Lymphocyte Reactions in Neonatal FlHybrid Rats
Authors: McCULLAGH P.
Published: August 2010

The subpopulation of parental‐strain lymphocytes responsible for the recognition of a particular F1hybrid strain as foreign has been shown to be subject to specific, reversible inactivation after its injection into neonatal rats of that F1hybrid strain. Neonates born to mothers that were syngeneic with the parental‐strain lymphocytes under test acquired the capacity to inactivate these lymphocytes at an earlier age than did the genotypically identical reciprocal F1hybrids. Neonates had little capacity to inactivate completely allogeneic lymphocytes. It is inferred from the difference in behavior between reciprocal F1hybrids that the augmented ability to inactivate anti‐F1hybrid maternal‐strain lymphocytes follows exposure to such cells in utero and to antibodies with anti‐F1hybrid activity in colostrum. Specific inactivation of those marauding maternal lymphocytes with anti‐fetal activity is envisaged as an important means of protection of the fetus from immunological attack by the mother. On the basis of the results presented in this and the preceding paper, it has been proposed that many of the sequelae of the transfer of immunocompetent parental‐strain cells to F1hybrid animals result not from graft anti‐host activity but from an F1hybrid anti‐parental lymphocyte response that has eluded normal regulatory mechanisms. These experiments also raise the possibility that regulation of auto‐immune responses may be achieved by the inactivation of lymphocytes with anti‐self reactivity by other lymphocytes that respond to the recognition structure required for such reactivity.
In Vivo Responses of Alloreactive Lymphocytes Stimulated In Vitro
Authors: CORLEY R. B. , KINDRED B.
Published: August 2010

Mouse lymphocytes that have been primed in vitro against alloantigens show a specific increase in cells reactive to the priming antigens in mixed lymphocyte response (MLR) and include cells that are specifically cytotoxic in vitro. The primed population also contains cells capable of causing rejection of skin grafts when injected into nude mice. Functional enrichment of cells capable of rejecting skin grafts bearing specific alloantigens and depletion of cells capable of rejecting a third‐party graft have been shown. Priming the cells a second time in vitro may result in a moderate enrichment of cells capable of rejecting the specific graft and depletion of cells reactive to third‐party skin compared with once‐primed cells. These findings support the prediction that the MLR is an in vitro model of allograft response in vivo.
Cross‐Idiotypic Reactions Among Anti‐Rh (D) Antibodies
Authors: FøRRE Ø. , NATVIG J. B. , MICHAELSEN T. E.
Published: August 2010

In a series of experiments several idiotype‐specific rabbit antisera produced against different IgG anti‐Rh (D) antibodies reacted with other anti‐Rh (D) antibodies and thus showed cross‐idiotypic reactions. Some of the antisera agglutinated almost all types of anti‐D‐sensitized erythrocytes, whereas other idiotype‐specific antisera agglutinated only a few anti‐D‐sensitized erythrocytes. Anti‐D antibodies showed several different cross‐idiotypic reaction patterns. The cross‐idiotypic antigens were, in most instances, localized to the heavy chains only. In a few cases, however, the cross‐idiotypic antigens were dependent on the interaction between heavy and light chains.
Removal and Refixation of Surface Ig from Isolated Rat Mast Cells
Authors: SKOV P. STAHL
Published: August 2010

This study showed that under well‐defined conditions all immunoglobulins could be removed from the rat mast cell surface. Surface immunoglobulins were examined by immunofluorescence technique, and cell function by the allergic reaction to antigen as judged by histamine release. Refixation of eluted surface Ig to the mast cell was easily accomplished. Furthermore, fixation of specific surface Ig to already sensitized cells resulted in inreased cell sensitivity to antigen, whereas fixation of nonspecific surface Ig resulted in decreased sensitivity. The results indicate that removed immunoglobulins are intact, have affinity for mast cells, and are able to compete with cell‐bound Ig.
Quantitative and Qualitative Estimations of IgE Bound to Basophil Leukocytes from Hay Fever Patients
Authors: SKOV P. STAHL , PERMIN H. , MALLING H.‐J.
Published: August 2010

IgE was removed from human basophils of 4 nonatopic persons and 10 hay fever patients allergic to timothy grass pollen by treating the cells with buffer to adjusted pH 4. IgE could be removed and refixed to the same cells. Refixation was demonstrated by immunofluorescence and by the ability of basophils to release histamine on exposure to timothy pollen. Removed total IgE and specific IgE directed against timothy pollen were estimated, and a linear correlation to the level of total IgE and specific IgE in serum was found. The total number of IgE molecules per basophil was calculated to be in the range of 30,000 to 300,000, and timothy‐specific IgE constituted 4%‐15% of the total IgE molecules on the cells. It was furthermore established that specific cell‐bound IgE was linearly correlated to the pollen concentration releasing 20% of the histamine contents of the basophils. Separated IgE from sensitized and nonsensitized basophils could be bound to basophils from other patients, resulting in a change in cell sensitivity. This could be ascribed to additional binding to free cell receptors as well as to a partial replacement of bound IgE. Basophils from nonatopic persons could not be sensitized by incubation with surface IgE from atopic persons. The results indicate that acid treatment is a simple method suitable for removing IgE from basophils. This IgE is intact and can be quantitated.
Poly A:U‐Induced Secretion of T‐Lymphocyte Helper Factors
Authors: BICK P. H. , JOHNSON A. G.
Published: August 2010

In vitro exposure of mouse thymocytes to complexes of polyadenylic:polyuridylic acid (poly A:U) effected, within 6 h, the release of soluble factor(s) capable of nonspecifically enhancing IgM and IgG plaque‐forming cells (PFCs) in in vitro primary and secondary spleen cell responses to burro erythrocytes. Poly A:U stimulation was, most likely, polyclonal, since production of soluble factor(s) occurred in the absence of antigen and in serum‐free culture media. Poly A:U‐induced soluble factor(s) were not capable of substituting for T cells but were dependent on T cells for the expression of PFC enhancement. These data support the hypothesis that the mechanism of poly A:U's adjuvant action is polyclonal stimulation of T cells, causing early induction and release of nonspecific, soluble PFC‐enhancing factor(s).
Migration Inhibition Produced by Sodium Periodate Oxidation of the Macrophage Membrane, and Reversal by Sodium Borohydride
Authors: FOX R. A. , FERNANDEZ L. A. , RAJARAMAN R.
Published: August 2010

Guinea pig peritoneal exudate cells were harvested 3 to 4 days after the intra‐peritoneal injection of Marcol oil. The washed cells were exposed to various concentrations of sodium periodate in phosphate‐buffered saline (PBS) at pH 7.4 for 10 min at +4°C. The cells were then used in the in vitro migration assay, and migration was consistently inhibited at concentrations from 10−3 to 10−5M. The viability of the macrophages was not affected by this treatment. Sodium borohydride (10−3 to 10−5M) in PBS for 10 min at pH 7.4 reversed the periodate effect. Experiments with purified macrophages showed that sodium periodate has a direct effect on macrophage function rather than an indirect effect via the potentiation of migration inhibition factor. In support of this, the in vitro spreading of macrophages on glass substrate foe 1 h has been shown to be inhibited. This spreading inhibition can also be reversed by treatment with sodium borohydride. These results provide a new approach to understanding the biological significance and role of macrophage migration inhibition.
Polyclonal Antibody Secretion in Human Lymphocytes Induced by Killed Staphylococcal Bacteria and by Lipopolysaccharide
Authors: RINGDEN O. , RYNNEL‐DAGÖÖ B. , WATERFIELD E. M. , MÖLLER E. , MÖLLER G.
Published: August 2010

Preparations of Staphylococus aureus strains Cowan 1 and Wood 46 and of lipopolysaccharide (LPS) were found to act as polyclonal B‐cell‐activating substances for human splenic and blood lymphocytes. All three substances induced polyclonal antibody secretion in blood and spleen cell cultures, as tested against fluorescein isothiocyanate‐coupled sheep erythrocytes by a modification of the local hemolysis‐in‐gel assay. Antibodies were of IgM class, as shown by inhibition of plaque formation by anti‐IgM but not by anti‐IgG or anti‐IgA antisera. All these substances also consistently induced the formation of intracellular immunoglobulin and Increased DNA synthesis in stimulated spleen cells. In blood lymphocytes Staph. aureus Cowan 1 induced a consistent increase in DNA synthesis, whereas Staph. aureus Wood and LPS often gave low or no increase in DNA synthesis. Peak antibody formation was observed on day 3 in spleen cells and on day 6 in blood lymphocyte cultures. Stimulation into high‐rate immunoglobulin secretion occurred with all PBAs also in B‐cell‐enriched cell suspensions but not in T‐cell‐enriched cells. Optimal responses were, however, always noted in unseparated cell suspensions. It is concluded that preparations of killed bacteria can be useful tools for the clinical evaluation of both specific and nonspecific antibody‐forming ability in cells from different groups of patients.
Boosting of Secretory IgA Antibody Responses in Man by Parenteral Cholera Vaccination
Authors: SVENNERHOLM A.‐M. , HOLMGREN J. , HANSON L. Å. , LINDBLAD B. S. , QUERESHI F. , RAHIMTOOLA R. J.
Published: August 2010

The occurrence of specific antibodies to Vibrio cholerae lipopolysaccharide in serum, milk, and saliva of Pakistani women from a very low socioeconomic group was studied before and after a single subcutaneous cholera vaccination. Before immunization all women had low levels of specific antibodies in serum, primarily of IgM class, and in many cases cholera IgA antibodies were found in milk and saliva as well, indicating earlier natural exposure. The vaccination consistently induced a marked rise in serum antibody titer, and notably also produced significant titer increases in 70% of the milk and in 45% of the saliva samples. Whereas the serum antibodies induced were predominantly of the IgG class, secretory IgA was responsible for most of the titer increase in the secretions. The results indicate that parenteral cholera vaccination can boost local secretory IgA antibody responses in intestinally primed individuals.
Thymic Microenvironment: Selective Activities of Soluble and Insoluble Components
Authors: ZOLLINGER L. , POTWOROWSKI E. F.
Published: August 2010

Two components of the thymic microenvironment have been separated, and their r biological properties have been studied. The first component, soluble thymic factor (STF), after injection into syngeneic recipients, provoked a temporary decrease in thymic weight on day 7, concomitant with an increase in the level of T cells in lymph nodes (but not in the spleen), followed by a general hyper‐trophy of lymph nodes peaking on day 21, In contrast, after the injection of the second component, insoluble thymic fraction (ITF), there was an increase in the number of prothymocytes in the thymic subcapsulary cortex, followed by general thymic hypertrophy on days 14 and 21. STF is believed to trigger a selective migration of lymph‐node‐seeking T cells from the thymus, whereas ITF seems to play a role in the differentiation step preceding that imparted by STT.