bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of silicone oil on protein adsorption to hydroxyapatite in vitro and on pellicle formation in vivo
Authors: RYKKE MORTEN , RÖLLA GUNNAR
Published: October 2007

Abstract – Silicone oil has been introduced in a dentifrice for smokers because of its effect as a polishing agent. Silicone oils are hydrophobic in character and have low surface tensions and good wetting properties. Due to the low surface tension, silicone oils may spread readily on solid surfaces and cover them with a thin, water‐repellant film. Introduced via dentifrices silicone oil may thus well be able to adsorb to enamel surfaces and to interfere with surface characteristics such as protein adsorption. The aim of the present study was to examine the effect of silicone oil on protein adsorption to hydroxyapatite (HA) in vitro and on pellicle formation in vivo. The effect on protein adsorption to HA in vitro was studied by adsorption of albumin to either untreated or silicone oil treated HA powders. Ion exchange chromatography was also used with either untreated or silicone oil treated HA as bed materials. The effect on pellicle formation in vivo was studied using enamel fragments carried in the mouth to acquire pellicle material. The chemical composition of the acquired pellicle was studied by collection and chemical analysis of pellicle material formed on enamel surfaces in vivo. The study showed that silicone oil treated HA took up less protein and that the adsorbed protein was bound to hydroxyapatite by a different mechanism as compared to untreated controls. The results indicated that hydrophobic interactions could be involved in binding of proteins to silicone oil treated hydroxyapatite. Silicone oil treated enamal fragments carried in the mouth showed a slower rate of pellicle formation as compared to untreated fragments. The amino acid composition of the acquired pellicle collected in vivo from silicone oil treated enamel surfaces was also different from pellicle material collected from untreated enamel.
Xylitol 5‐P formation by dental plaque after 12 weeks' exposure to a xylitol/sorbitol containing chewing gum
Authors: Wåler Sonni Mette , Assev Synnöve , Rölla Gunnar
Published: October 2007

Five subjects used xylitol‐containing chewing gum for 12 wk. Dental plaque was collected before and after the exposure to xylitol. The plaque samples were examined for their capacity to form xylitol 5‐P by incubation with 14C labeled xylitol, extraction and separation on HPLC. It was found that the capacity of the plaque to form xylitol 5‐P was not reduced during the xylitol exposure in any of the subjects. No other xylitol‐derived metabolites were observed. The inhibitory capacity of xylitol thus appears to be maintained after 12 wk exposure to xylitol.
Sensitivity to a low calcium diet in different bones: an experimental study in the adult rat
Authors: Rosenquist J. B. , Lundgren S.
Published: October 2007

Adult male Sprague‐Dawley rats weighing an average of 550 g were age matched into one control group and one group given a low calcium diet. The animals were followed for 34 wk. There was a similar loss of cancellous bone tissue in the proximal tibia, the first tail vertebra and the mandible due to calcium deficiency. The bone loss was not related to the initial amount of cancellous bone or to the bone‐forming activity, which did not differ between experimental and control animals.
Effects of food preservatives on growth and metabolism of plaque bacteria in vitro and in vivo
Authors: Leikanger Synnøve , Bjertness Espen , Scheie Anne Aamdal
Published: October 2007

The aims of the present study were to assess the consumption of food preservatives during the last decades, and to study the effect of the preservatives, sorbic and benzoic acid, on growth and glycolysis of oral bacteria in vitro, and on acid formation by dental plaque in vivo. Five consumption reports from the Central Bureau of Statistics of Norway were used to estimate alterations in consumption of staple food containing the two preservatives. A modified broth dilution method was used to determine the MIC values of the preservatives against Streptococcus sobrinus and Streptococcus sanguis. Extracellular 14C‐glycolytic metabolites were studied by HPLC analyses. Plaque‐pH measurements were used to assess possible effects on acid production. The consumption reports indicated increased consumption of preservatives. The in vitro testing suggested that legal concentrations of preservatives may inhibit the growth of oral streptococci. However, the preservatives did not inhibit in vitro glycolysis at tested concentrations. In vivo testing with similar concentrations (0.4% w/v) showed a significant effect. A higher concentration (2% w/v potassium sorbate) had a tendency to inhibit acid‐formation by dental plaque even more.
Sizes of dental arches and general body growth up to 6 years of age in children with isolated cleft palate
Authors: Nyström Marjatta , Ranta Reijo , Kataja Matti
Published: October 2007

Development of the dental arches and height and weight at the ages of 3 yr and 6 yr were studied longitudinally in 60 children with isolated cleft palate (CP) and in 50 noncleft (NONC) children. Retrospective comparisons were also made in the CP group with arch size at the age of 0.2 yr and 1.8 yr. Anterior width at 0.2 yr of age was associated with canine width at the age of 3 yr (r = 0.70) and 6 yr (r = 0.60). Change in maxillary posterior width from 3 yr to 6 yr of age was related to the extension of the cleft, so that in the group with total cleft this dimension diminished. Measured in standard deviation scores (SDS), the means of maxillary width at canines and primary second molars in CP children varied from −1.0 to −2.0 and mandibular dimensions from ‐0.6 to ‐1.4. Discrepancy in arch depth diminished with age. Body size differed less from normal than the size of the dental arches. At 3 yr of age the height was −0.4 SDS in CP boys and −0.5 SDS in CP girls, but at 6 yr of age only −0.1 SDS in both boys and girls. Correlations between body size and the size of the dental arches were generally low (r < 0.20) both in CP and NONC children. The small size of the dental arches in CP children does not seem to be merely a reflection of the overall smaller size of CP children.
Amalgam – Fact and fiction
Authors: Molin Carl
Published: October 2007

A brief history of amalgam is given, stressing the role of G. V. Black. The background and the progress of the two Amalgam Wars are sketched. Aspects are presented of the drawbacks of amalgam with respect to toxic effects of, especially, mercury vapor and corrosion products. An account is given of some frequent fallacies concerning the health hazards of dental amalgam fillings and the role of psychosocial factors in the development of illness attributed to amalgam is emphasized.
Cortical bone mineral density in the mandible and osteoporosis status in postmenopausal women
Authors: Klemetti Esa , Vainio Pauli , Lassila Veijo , Alhava Esko
Published: October 2007

Mineral density of the cortical bone of the mandible was determined by single‐energy QCT (quantitative computed tomography) for 77 menopausal women. Bone mineral densities (BMD) were measured in the buccal and lingual layers of the cortex, distally from the foramen mentale, on both sides of the mandible. All the women were edentulous in that region, and the alveolar processes were far resorbed. These results were compared with the BMD values of the femoral neck, lumbar spine, and trabecular portion of the mandible between the detected layers of cortex. The BMD of the buccal cortex correlated remarkably well with all values, except those of the trabecular portion. Of the women tested, the correlations were lowest in the least osteoporotic group. The values for the lingual cortex did not correlate with other variables as well as did those for the buccal cortex, but in the most osteoporotic part of the sample the lingual cortex values correlated significantly with the BMD of the trabecular portion. The BMD values for the buccal cortex were significantly higher than those for the lingual cortex.
Hypodontia in 9‐year‐old Norwegians related to need of orthodontic treatment
Authors: Aasheim Borghild , Ögaard Björn
Published: October 2007

The present study reports on the prevalence of hypodontia in a Norwegian population and classifies children with hypodontia according to need of orthodontic treatment. Orthopantomograms of 1953 children (960 girls and 993 boys) at the age of 9 were available for examination. Of the boys registered with hypodontia of second premolars at the age of 9, 11.3% showed late mineralization between the ages of 9 and 12. Only 2.9% of the girls showed late mineralization. The corrected prevalence of hypodontia, excluding third molars, in the girls was 7.2%, in the boys 5.8%, and in both sexes combined 6.5%, the difference between sexes not being statistically significant. Of the children with hypodontia, 86.6% lacked only one or two permanent teeth. The most frequently missing teeth were the mandibular second premolars, the maxillary second premolars, and the maxillary lateral incisors, in that order. Classification of children with hypodontia according to need of orthodontic treatment showed that about two‐thirds had hypodontia only of single posterior teeth with a moderate need of treatment. About one‐third had hypodontia involving anterior teeth, and only 3.1% had hypodontia of two or more teeth in the same quadrant with a great need of treatment.
Reactivity of young and old human enamel to demineralization
Authors: Gängler Peter , Norén Jörgen G. , Hoyer Ingrid , Bjarnason Sibilla , Kraft Ulrike , Odelius Hans , Wucherpfennig Guido
Published: October 2007

The aim of this study was to determine the susceptibility of newly erupted and old permanent teeth to artificial, caries‐like attacks. Two groups of caries‐free teeth were used. Group 1 consisted of 38 teeth extracted for orthodontic reasons (9–12‐yr‐old children); group 2, of 40 teeth extracted for periodontal reasons (45–65‐yr‐old patients). After thorough cleaning, a test window was isolated on the incisal two‐thirds of the buccal surface. After demineralization with 6% HEC gel at pH 4.9 for 8 days, longitudinal ground sections were prepared for imbibition studies in polarized light and for secondary ion mass spectrometry (SIMS). In the young teeth, the lesions appeared to be uniform in their extension in the enamel, whereas the old teeth showed less marked and thinner surface zones and greater depth of the positively birefringent body of the lesion. Polarized light microscopy and SIMS data support the hypothesis that there are different enamel pathways in the initiation of the natural carious process.
An investigation of some factors associated with occlusal tooth wear in a selected high‐wear sample
Authors: Johansson Anders , Haraldson Torgny , Omar Ridwaan , Kiliaridis Stavros , Carlsson Gunnar E.
Published: October 2007

The aim of the present study was to investigate the influence of some factors associated with occlusal tooth wear in a selected high‐wear Swedish sample. The material comprised 59 persons having a mean age of 35 yr within the range 16–70 yr, the criteria for selection being a full or near‐full complement of natural teeth, and the presence of definite clinical signs of occlusal wear. A dentition wear index, in addition to anterior, posterior, and arch subindices, was derived from a tooth‐by‐tooth evaluation of casts. Factors which were found to correlate significantly with increased occlusal wear were age, sex, self‐perception of wear, number of teeth, and general health, as well as a number of variables from study‐cast analysis. On the basis of the findings, not only is the multifactorial etiology of occlusal tooth wear a reality, but so, too, is the complex interdependence of these factors in the severity of wear.
Three methods of oral health education in secondary schools
Authors: Laiho M. , Honkala E. , Nyyssönen V. , Milen A.
Published: October 2007

In 1990, three methods of oral health education (OHE) were implemented in three secondary schools in the city of Pori, Finland, one method in each school. The traditional OHE consisted of a lecture given by a dentist with the aid of transparencies and slides. The peer OHE consisted of a lecture given by six pupils from the upper grades. These pupils used transparencies and extracts of video films and had a classroom exhibition with pictures, slogans, and dental aids and instruments. The self‐teaching OHE was based on an exhibition from which the pupils searched for the information themselves. After the programs, the pupils' opinions about the method itself, its contents and implementation, knowledge about certain oral health issues, and the possible effect of the method were determined by a questionnaire. The attitudes and opinions were most positive in the peer OHE group. The traditional OHE was quite well accepted, but the self‐teaching method was not very successful. The participants in the traditional OHE more often felt that they had been encouraged to pursue good oral health habits. In all groups, the topic considered to be the most boring was tooth brushing. Peer OHE can be recommended for Finnish secondary schools. The issue of tooth brushing should be played down, however, as too frequent repetition of the topic may cause more negative attitudes towards oral health education and practices.
Dental plaque and caries on permanent first molar occlusal surfaces in relation to sagittal occlusion
Authors: Ekstrand Kim Rud , Nielsen Lis Aimer , Carvalho Joana Christina , Thylstrup Anders
Published: October 2007

This study examines the influence of sagittal occlusion on occlusal plaque formation in permanent first molars (PFM) in 72 7–10‐yr‐olds before loss of primary second molars. Of a total of 288 PFM, 140 (49%) were sealed and 23 (8%) filled. Occlusal plaque was recorded at two levels of examination: 1) visible plaque on the entire surface and 2) detailed macromorphologic mapping. Enamel caries was recorded after professional tooth cleaning. After 48 h without tooth brushing, plaque examinations were repeated. Stone models were used for 1) identification of interocclusal contact areas and 2) classification of sagittal molar occlusion. The detailed mapping of plaque on unfilled surfaces showed a clear pattern of preferential locations related to the macromorphology of the occlusal surfaces. Active caries was restricted to those anatomic structures where plaque accumulated. 48‐h median plaque values on mandibular molars in normal and with one cusp distal occlusion were significantly lower (P < 0.01) compared to surfaces in 1/4, 1/2 and 3/4 distal molar occlusion. Maxillary molars with normal and with 1 cusp distal occlusion had lower median plaque values than other sagittal occlusion categories. In general, however, plaque scores were higher in maxillary teeth because more than 2/3 of these teeth were without occlusal contact in the distal part. Mandibular occlusal surfaces in normal and with one cusp distal occlusion had significantly fewer active lesions than teeth with 1/4, 1/2 and 3/4 cusp distal occlusion. The significant influence of variations in sagittal molar relation on occlusal plaque formation and caries initiation occurring in fully erupted PFM before loss of primary second molars thus supports the view that physical forces operating during mastication are an important factor for colonization and growth of bacteria with cariogenic potential.
Variation in torus palatinus prevalence in Norway
Authors: Eggen Svein , Natvig Bent , Gåsemyr Jørund
Published: October 2007

The variation in lorus palatinus (TP) prevalence was investigated among a total of 2010 denial patients over 10 yr of age native to two different regions in Norway, the Lofoten Islands in northern Norway and the Gudbrandsdalen valley, an inland area in the southeastern part of the country. The two groups were presumed to belong to the same Caucasian stock, but were extremes with regard to the fish‐to‐meat ratio of the diet, which was 3:1 in Lofoten and 1:3 in Gudbrandsdalen, respectively representing a soft type of diet, and a tough type requiring greater muscular forces during mastication. The study revealed: 1) the prevalence of TP was higher among women than men; 2) TP seemed likely to arise from a multifactorial liability, with part of the genetic factors residing on the X chromosome; 3) the prevalence of TP appeared to be higher among natives of Lofoten, who consume the softer food, than among natives of Gudbrandsdalen, the higher prevalence being hypothesized to have some connection with nutrient substances present in saltwater fish, possibly Ω3 polyunsaturaled fatty acids and vitamin D; and 4) TP seemed to be a dynamic phenomenon capable of growth and subject to resorption remodeling.
Influence of pH and calcium on growth and attachment of human fibroblasts in vitro
Authors: Lengheden Annelie
Published: October 2007

Human embryonic diploid lung fibroblasts (HEDL fibroblasts) and periodontal ligament fibroblasts (PDL fibroblasts) were cultured in media at fixed pH levels ranging between 7.2 and 8.4 and fixed calcium concentrations ranging between ≤100 μM and 20 mM in an attempt to mimic the effects of calcium hydroxide on vital cell functions such as attachment and growth. PDL fibroblasts appeared to be more susceptible to changes in pH and calcium concentration than HEDL fibroblasts. At pH levels above 7.8, both attachment and growth decreased significantly. Growth was influenced more by changes in pH and calcium concentration than was attachment. The results help explain why intracanal application of calcium hydroxide through its high pH may impair periodontal healing in areas on the root surface where the cementum has been damaged by either trauma or periodontal treatment, thus allowing the medicament access to the root surface.
Systemically induced contact dermatitis from dental rosin
Authors: Bruze Magnus
Published: October 2007

Rosin is a ubiquitous contact sensitizer which may be present in dental materials such as periodontal dressings, impression materials, cements, and cavity varnishes. When a hypersensitive person is exposed to a sensitizer, allergic contact dermatitis/stomatitis may develop, most commonly after direct skin/mucosa contact with the sensitizer. However, widespread dermatitis may develop after systemic administration of the sensitizer, and this paper reports the case of a rosin‐hypersensitive man who developed widespread eczematous dermatitis after dental treatment with a rosin‐containing product.
A structural analysis of approximal enamel caries lesions and subjacent dentin reactions
Authors: Bjørndal Lars , Thylstrup Anders
Published: October 2007

The present study examines the correlation between caries lesions in enamel and the corresponding dentin reactions in proximal tooth surfaces with lesions ranging from enamel lesions to cavitations without dentin exposure. Using quantitative imbibition technique, the highest degree of tissue porosity, irrespective of lesion activity, was always noted along a Central‐Traverse (CT), which followed the direction of the rods from the deepest point of penetration to the surface. The conical shape of approximal enamel lesions can thus be seen as the result of systematic variations in porosity along the rods determined by the specific interproximal environment. The initial dentin reaction, related to the enamel lesion approaching the enamel–dentin junction (EDJ), was seen as a local dentin translucency where the CT crossed the EDJ. Results from histomorpho‐metric analyses revealed that, when the enamel lesions reached the EDJ, brownish discoloration in the dentin never exceeded the histologic contact area between the enamel lesion and the EDJ. In relation to the less advanced parts of the individual enamel lesion, the dentin responded with formation of translucent dentin. These reactions did not occur beyond an area determined by lines in the direction of the rods from the peripheral part of the enamel lesion towards the EDJ. The results did not support the view that dentin caries spreads along the enamel‐dentin junction. The peripheral dentin translucency is therefore generated by stimuli transmitted along the rods of the less advanced parts of the enamel lesions.
The toothpick method in relation to other plaque sampling techniques for evaluating mutans streptococci
Authors: Wennerholm Kerstin , Lindquist Birgitta , Emilson Claes‐Göran
Published: October 2007

The aim of the present study was to compare the use of toothpicks with other sampling methods for determination of mutans streptococci on different tooth surfaces. In nine persons with > 105 CPU per ml saliva of mutans streptococci, plaque samples were taken from 90 buccal and lingual surfaces. 108 occlusal surfaces and 90 approximal surfaces with toothpicks. The prevalence of mutans streptococci on these tooth surfaces was compared with samples taken at four 1‐week intervals on the same tooth surfaces with a carver (buccal/lingual surfaces), a needle (occlusal surfaces) or a dental floss (approximal surfaces). Each sample was plated on MSB agar and the presence of mutans streptococci was expressed on a scale varying from 0 to 4. On two of the sampling occasions the amount of plaque, mirrored by total viable counts on blood agar, was also determined. Only for buccal/lingual plaque samples was a difference in total counts between methods noted and then with higher total recoveries obtained after sampling with toothpicks. More surfaces were found to be positive for mutans streptococci when samples were taken with a toothpick than with a carver, needle or floss. On surfaces positive for mutans streptococci the colonization score was higher in samples taken with a toothpick than with a carver or a needle while samples taken with a floss showed a tendency to higher levels of mutans streptococci than samples collected with a toothpick. The data indicate that the results obtained by using toothpicks for evaluating the prevalence of mutans streptococci an individual tooth surfaces compare favorably with the other methods tested
Validity of the Children's Dental Fear Picture test (CDFP)
Authors: Klingberg Gunilla , Löfqvist Lena Vannas , Hwang C. Phillip
Published: October 2007

The validity of the Children's Dental Fear Picture test (CDFP) was investigated in 146 Swedish children aged 5–12 yr. The CDFP was compared with dental fear scores on Children's Fear Survey Schedule – Dental Subscale (CFSS‐DS), selection criteria for testings (dentally fearful/not dentally fearful), and with level of general fear measured by the Short Form of Children's Fear Survey Schedule (CFSS‐SF). Dental fear in the CDFP was closely related to high scores on CFSS‐DS and CFSS‐SF. The CDFP proved to be a valid instrument to diagnose dental fear in children with values of sensitivity up to 98.5%.
Characterization of interstitial collagenases in jaw cyst wall
Authors: Teronen O , Salo T. , Laitinen J. , Töwall J. , Ylipaavalniemi P. , Konttinen Y.T. , Hietanen J. , Sorsa T.
Published: October 2007

Neutral salt extracts of 14 specimens of jaw cysts were prepared. Histopathological analysis showed that the specimens consisted of 6 radicular cysts, 6 dentigerous cysts, 1 residual cyst, and 1 odontogenic keratocyst. One periapical granuloma, J dental follicle and a sample of clinically healthy oral mucosa were similarly processed and used as controls. Measurement of collagenase activity by monitoring the formation of specific degradation products of type I and II collagen in solution by SDS‐PAGE demonstrated that all the cyst extracts contained collagenase, some of which was endogenously activated. Cyst wall collagenase preferably degraded type 1 over type II collagen, which suggests that the degradation was due to MMP‐1 (matrix metalloproteinase‐1) rather than the MMP‐8 type. This was further supported by the doxyeycline‐inhibition profile of cyst collagenase, which was similar to that of MMP‐1. Part of the cyst wall collagenase was in latent proenzyme form and probably derived, at least in part, from the newly synthesized intracellular collagenase pool. Latent cyst collagenase was efficiently activated with phenylmercuric chloride and to a lesser extent by gold (I) thioglucose and NaOCl, Western‐blotting, using specific antibodies against collagenase from human polymorphonuclear neutrophilic leukocytes (MMP‐8) and from fibroblasts (MMP‐1), revealed a typical 55/45 kDa doublet: also MMP‐8 in the latent 80 kDa form and fragmented to 65 kDa active species were found. These results suggest the presence of MMP‐1 and, to a lesser extent. MMP‐8 type collagenase in the cyst wall. The presence of partially activated interstitial collagenases in the cyst wall may contribute to cyst wall remodeling and may thus, in part, regulate cyst growth.
PH effects on experimental wound healing of human fibroblasts in vitro
Authors: Lengheden Annelie , Jansson Leif
Published: October 2007

The aim of the present study was to examine to what extent pH affects human fibroblast repopulation of an experimental wound in vitro laying special emphasis on cell migration, DNA synthesis, and alterations in cell morphology. Wounds were simulated in vitro by partially scraping off monolayers of human embryonic diploid lung fibroblast and human periodontal ligament fibroblast‐like cells respectively. The wounded monolayers were cultured at pHs ranging from 7.2 to 8.4. The experiments were evaluated by autoradiography as well as light and scanning electron microscopic techniques. A significant, approximately linear, decrease was noted both in cell migration into and DNA synthesis in the experimental wounds as a result of pH increase. The surviving cells in the wounds showed cytoplasmatic vacuoles and blebbing at pH levels above 7.8. Clinical implications of these results for endodontic calcium hydroxide treatment are that hydroxyl ions, diffusing through root dentin, may interfere with vital cell functions necessary for healing on the root surface.
Tissue reaction to gutta‐percha particles of various sizes when implanted subcutaneously in guinea pigs
Authors: Sjögren Ulf , Sundqvist Göran , Nair P.M. Ramachandran
Published: October 2007

Tissue reaction to gutta‐percha was studied using subcutaneously implanted Teflon cages in guinea pigs. Gutta‐percha was tested in three forms: (i) as large particles prepared by dividing gutta‐percha cones into pieces, (ii) as fine particles prepared by ball‐milling of gutta‐percha, and (iii) as particles produced by dissolving gutta‐percha in rosin‐chloroform. Gutta‐percha evoked two distinct types of tissue response. The large pieces were well encapsulated and the surrounding tissue was free of inflammation. The fine particles evoked an intense. localized tissue response, characterized by the presence of macrophages and multinucleated giant cells. The rosin‐chloroform treated gutta‐percha induced a similar tissue reaction to that observed with the fine particles of gutta‐percha. In addition, cell remnants were present in association with the material, which indicates an initial toxicity to rosin‐chloroform treated gutta‐percha. These results show that the size and surface character of gutta‐percha can determine the type of tissue reaction to the material. The accumulation of macrophages around gutta‐percha may be an important factor in the impairment of healing of periapical lesions when teeth are root filled with excess material.
Influence of light intensity on polymerization shrinkage and integrity of restoration‐cavity interface
Authors: Feilzer A.J. , Dooren L.H. , de Gee A. J. , Davidson C. L.
Published: October 2007

The results of this study showed that the use of high intensity curing light units negatively affected the integrity of the restoration‐cavity interface in class V restorations, This is explained by the high reaction rates of light curing resin composites. The interfacial integrity was better preserved with low light intensity as it extends the visco‐elastic stage of the setting materials, thereby moderating the setting stress development. The ultimate polymerization shrinkages for both conditions were equal, which suggested equal degrees of conversion and thus equal material properties. The results may alleviate the trend in using higher intensity light curing units and in particular the development of units with laser beams in an attempt to further increase conversion rates.
Agenesis of permanent incisors in a mediaeval maxilla and mandible: aetiological aspects
Authors: Sejrsen Birgitte , Kjær Inger , Jakobsen Jan
Published: October 2007

A paleopathological maxilla and mandible with tooth agenesis were analyzed, focussing on the aetiology of the condition. The jaw material, derived from an adult mediaeval male, was examined by standard anthropological analyses, including radiography. In the maxilla there was agenesis of three permanent incisors and one premolar, and in the mandible of one permanent incisor and two permanent molars. Absence or marked reduction of the incisive foramen and the nasopalatine canal was found. The pattern of tooth agenesis was similar to the pattern observed in contemporary individuals, except for the agenesis of one permanent maxillary centreal insisor. It is suggested that the pronounced lack of the premaxillary area of the nasopalatine canals and the incisive foramen. As the condition can be ascribed to deviations in the prenatal developments, this investigation shows that embryological developmental patterns, which form the basis for the pattern of tooth agenesis, should be taken into account when evaluation dry bonde patholgy.
Effects of essential fatty acid deficiency on rat molar pulp cells
Authors: Vermelin Laurent , Ayanoglou Charles , Septier Dominique , Carreau Jean‐Paul , Bissila‐Mapahou Paul , Goldberg Michel
Published: October 2007

In rats fed an essential fatty acid deficient (EFAD) diet, either during pregnancy (DN) or for 4 wk postnatally (ND), the cell density in the central part of the pulp increased about two‐ and threefold, respectively, of that in rats who had received a conventional diet containing sunflower oil. Cells were especially numerous around capillaries. The cell density was also increased twofold in the subodontoblastic layer in the outer part of the pulp, cells being smaller in ND compared with DN. In contrast, the‐ odonloblasts were reduced in height, and the Hohl cells formed a thin layer in EFAD rats. This emphasizes some aspects of pulp specificity which reacted differently from odontoblasts. We suggest that the function of killer cells which normally destroy cells at the periphery of the pulp may be impaired by the diet, leading to cell accumulation.
Effects of the antihypertensive drug captopril on human salivary secretion rate and composition
Authors: Nederfors Tommy , Dahlöf Carl , Ericsson Thorild , Twetman Svante
Published: October 2007

The effects of the antihypertensive drug captopril on salivary secretion rate and composition was evaluated in 24 healthy adults (18–46 yr) according to a double‐blind, cross‐over design. Unstimulated and paraffin‐chewing stimulated whole saliva and 3% citric acid stimulated parotid and submandibtilar‐sublingual (SM‐SL) secretion were collected at 10.30 a.m. (about 2h after intake of breakfast) on day 0 (baseline values), day 1 (experimental acute values) and day 7 (experimental chronic values) in each treatment period. In 8 of the subjects, also morning samples were collected at 7.30 a.m., with the test subjects in a fasting condition. Whole saliva was assessed for flow rate and for concentrations of sodium, potassium, chloride, calcium and phosphate. In addition, parotid and SM‐SL secretion were assessed for concentrations of total protein, hexosamine. sialic acid, lactoferrin and salivary IgA and for activities of amylase. lysozyme and salivary peroxidase. During treatment with the angiotensin converting enzyme inhibitor captopril, the secretion rates tended to increase for unstimulated and paraffin‐chewing stimulated whole saliva and for parotid secretion. For salivary composition, no alterations were observed in any of the collected secretions.
Excavation of caries lesions induces transient decrease of total salivary immunoglobulin A concentration
Authors: Kugler Joachim , Breitfeld Iris , Tewes Uwe , Schedlowski Manfred
Published: October 2007

Salivary immunoglobulin A (IgA) secreted by salivary glands is the predominant humoral factor of the local immune system in the oral cavity. Epidemiological studies emphasize the importance of salivary IgA in the protection from infections and caries. This study investigated how excavation of caries lesions affects total salivary IgA concentration. Fifteen patients were assigned to two sessions: the first session consisted of the excavation of a caries lesion. Thirty min before, during, directly after, and 30 min after the excavation, patients were asked for saliva samples. One wk later, a control session was performed on the same patients at the same time of the day, consisting of a dental inspection without any drilling. Marked, transient decreases were observed in concentration and secretion rate of total salivary immunoglobulin A during and immediately after caries excavation. Thirty min after caries excavation, immunoglobulin A concentrations returned to baseline. No differences were found between sessions with regard to saliva flow and cortisol concentration. It was concluded that transient decreases of total salivary immunoglobulin A concentrations are induced by excavation of caries lesions.
Detection by physico‐chemical techniques of an amphiphilic surface component on Streptococcus mitis strains involved in non‐electrostatic binding to surfaces
Authors: van der Mei Henny C. , Busscher Henk J.
Published: October 2007

Indications for the presence of an amphiphilic molecule in Streptococcus mitis strains cultured on TY‐agar were obtained from infrared absorption spectra, especially from the shape of the CH2/CH3 absorption bands around 2900 cm−1, which were absent when strains were grown on blood agar. It was the aim of this study to determine for 5. mitis strains grown on different growth media whether the amphiphile is located intracellularly or on the cell surface by measuring zeta potentials, elemental surface compositions and adhesion to hexadecane of differently grown cells. There was no significant effect of the presence of the amphiphile on the zeta potentials of the S. mitis strains, but adhesion to hexadecane was increased by the presence of the amphiphile when the pH of the suspension was such that electrostatic interactions between the organisms and the hexadecane could be neglected. Furthermore, lower N/C surface concentration ratios were found for organisms possessing the amphiphilic molecule. Consequently, it was concluded that the amphiphilic molecule is located on the cell surface, and that it is involved in the non‐electrostatic binding of S. mitis cells to surfaces.
Four‐year evaluation of the effect of 10% polyacrylic acid or water rinsing pretreatment on retention of glass polyalkenoate cement
Authors: van Dijken J. W. V.
Published: October 2007

To optimize the bonding of glass polyalkenoate (ionomer) cement to dentin, different conditioning methods have been suggested. The effect of two easily applied conditioning methods, a 10‐15 seconds cleaning with a 10% polyacrylic acid or rinsing with copious amounts of water, was compared in class V abrasion/erosion lesions. The cervical lesions were restored, without any form of mechanical cavity preparation, with an anhydrous glass ionomer cement. During a 4‐yr period. 137 restorations were evaluated every 6 months. Cumulative loss rates after 4 yr were 15.6% for the polyacrylic acid group and 21.9% for the water rinsing group. The difference was not significant. No secondary caries was registered.
A fiber‐optic setup for quantification of root surface demineralization
Authors: van der Veen M. H. , ten Bosch J. J.
Published: October 2007

A fiber‐optic fluorescence observation (FOFO) technique has been developed for the quantification of demineralized root dentin. The method was tested on 40 specimens of in vitro demineralized parts of human root dentin. Fluorescein sodium salt was used as a penetrating dye. The fiuorescein sodium salt was excited using light around 465 nm. The fluorescence signal around 527 nm measured for demineralized dentin was corrected for lamp output and then divided by the corrected fluorescence signal for the sound control dentin on the same root, resulting in a FOFO‐value. FOFO‐values correlate linearly (r=0.91) with mineral loss measured by transverse microradiography. Therefore, it was concluded that the FOFO‐technique provides a good, non‐destructive measure of the severeness of in vitro demineralized human root dentin, and is applicable on bulk dentin. Future work on natural lesions in vivo will be needed to investigate the applicability of the technique in a clinical situation.
Comparison of two‐and three‐body wear of glass‐ionomers and composites
Authors: Pelka Matthias , Ebert Johannes , Schneider Harald , Kramer Norbert , Petschelt Anselm
Published: October 2007

The two‐body and three‐body wear of glass‐ionomers (GIC), visible light cured glass‐ionomers (VLC‐GIC), and composites were compared. The wear simulations were performed for the two‐body wear in an artificial mouth and for the three‐body wear with the so‐called ACTA machine. The tested materials were different conventional glass‐ionomers. light cured glass‐ionomers. composites, and amalgam. The wear rates of 8 specimens of each material for the two‐body and 16 for the three‐body wear test were compared. After 105 cycles with each testing device, the wear shapes were measured. All measurements were related to the wear rate of amalgam. For the two‐body wear method, the worn materials were qualitatively judged by scanning electron microscopy. The two different wear testing methods lead to similar results with slight differences in ranking. Amalgam showed the lowest wear rates with both methods. Photac® Fil, a newly developed VLC‐GIC. showed dramatically lower wear resistance than composites and conventional GIC with both methods. Further investigations are necessary to identify the material‐specific parameters influencing the wear behaviour of a material in relation to different wear testing methods.
Disaccharide analysis of chondroitin sulfate in peri‐implant sulcus fluid from dental implants
Authors: Okazaki Joji , Gonda Yoshimichi , Kamada Aiko , Sakaki Tetsuya , Kitayama Nobuhiro , Kawamura Tatsuya , Ueda Minoru
Published: October 2007

We collected peri‐implant sulcus fluid by capillary tubes from sites around titanium osseointegrated implants and determined the chondroitin sulfate released into the peri‐implant sulcus fluid by high‐performance liquid chromatography. Chondroitin sulfate was found in all peri‐implant sulcus fluid samples, and its content was similar to that in gingival crevicular fluid obtained around natural teeth. The predominant unsaturated disaccharide isomer was ΔDi‐OS, followed by ΔDi‐4S. ΔDi‐6S was present in trace amounts. The amount of ΔDi‐OS was greater in peri‐implant sulcus fluid than in gingival crevicular fluid. Assaying chondroitin sulfate disaccharides in peri‐implant sulcus fluid may be an effective method of monitoring the peri‐implant condition of dental implants.
Etiology of dental erosion – extrinsic factors
Authors: Zero Domenick Thomas
Published: October 2007

The extrinsic causes of dental erosion can be grouped under the headings of environmental, diet, medications and lifestyle. Environmental factors mainly involve exposure to acid fumes by workers in factories without proper safeguards. Swimming pools with low pH due to inadequate maintenance have also been implicated. Dietary factors have received the most attention and are likely to affect the broadest segment of the population. Most acidic foods and drinks have the potential to cause dental erosion in the human mouth. The total acid level (titratable acid) of dietary substances is considered more important than their pH, because it will determine the actual H+ available to interact with the tooth surface. Other constituents of foods and beverages will also have a modifying effect, including the calcium, phosphate and fluoride concentration, the acid type, and physical and chemical properties that influence the clearance rate from the mouth. It is not appropriate to assign relative degrees of risk to the different dietary substances except in general categories, because of the many human biological and behavioral factors that influence the clinical expression of dental erosion. The types of foods and beverages consumed, and the frequency and time of consumption are lifestyle factors that are considered most important regarding the clinical development of dental erosion. Low pH medications and oral hygiene products have also been suggested as potential causes of erosion. The combination of frequent consumption of acidic substances and overzealous oral hygiene practices may be another high risk lifestyle factor.
Dental erosion Clinical diagnosis and case history taking
Authors: Lussi Adrian
Published: October 2007

Dental erosion is not a very rare condition. Early correct diagnosis of this damage of dental hard tissue consequently is of clinical importance. The aim of this paper is to present an easy‐to‐learn rating scheme for the assessment of the severity of dental erosive lesions with high inter‐ and intra‐examiner agreement. It differentiates between facial, occlusal and oral surfaces of a tooth and has already been used successfully in epidemiological studies. Further, anamnestic risk factors are discussed with respect to their relevance for the development of dental erosion. Guidelines are given for the clinician on how to elicit information from the patient about relevant risk factors.
Methods of assessing erosion and erosive potential
Authors: Grenby Trevor H.
Published: October 2007

Methods for use in vitro are reviewed first, classified under the examination of extracted teeth, chemical and physical methods, digital image analysis, scanning electron microscopy and other potentially useful techniques. Methods for recording erosion in laboratory animals are dealt with next, including techniques that can also be used in vitro, Restarski's system and various modifications of it, and digital image analysis. Thirdly the main systems and indices that have been designed for clinical use are arranged under case histories and clinical examination, scales of severity and indices of diagnosis of varying complexity. Finally, some of the main advantages and limitations of the techniques are summarized.
Lessening dental erosive potential by product modification
Authors: Grenby Trevor H.
Published: October 2007

Current interest in dental erosion has led to increasing attention to ways in which potentially erosive products might be modified. Information on how this could be achieved has been hard to gather, and has focused chiefly on possibilities in reformulating soft drinks. The bulk of the work published on this relates to calcium and phosphate supplementation, ranging from early experimentation on saturation of a demineralising medium with tricalcium phosphate, through tests of more soluble phosphates and other calcium salts providing various levels of Ca2+ and PO43‐, to a calcium citrate malate additive specially formulated to curb erosion by soft drinks. Opinions on the effectiveness of citrate, the practicability of reducing the acidity levels of soft drinks, and the possible applications of fluoride, bicarbonates and certain constituents of milk products are also included. Finally, an attempt has been made to summarize some of the advantages and shortcomings of the different methods, but it is clear that much further work will be needed before firm guidelines on the best routes to product improvement can be laid down.
Emotional stress effects on immunity, gingivitis and periodontitis
Authors: Breivik Torbjørn , Thrane Per S. , Murison Robert , Gjermo Per
Published: October 2007

Gingivitis and periodontitis are thought to result from an imbalance between those oral microorganisms which normally colonize tooth surfaces in close contact with the gingival margin, and the nature and efficiency of the host response. The bacteria are the triggering agents, but host defence mechanisms within the gingival/periodontal tissues seem to be responsible for most of the tissue damage and for the outcome and progression of the diseases. It has recently been shown that emotional or psychological load (stress) may influence immune activities directly via neurvoendocrine (hormone) messenger substances (neurotransmitters and neuropeptides) and/or indirectly via neuroendocrine (hormone) substances. This review discusses how emotional stressors and nervous and neuroendocrine responses to psychological stressors may modulate the immune response to bacteria, and thus be expected to influence the progression and course of gingivitis and periodontitis.
Analysis of the concentration and output of whole salivary constituents in patients with Sjögren's syndrome
Authors: van der Reijden W. A. , van der Kwaak J. S. , Veerman E. C. I. , Amerongen A. V. Nieuw
Published: October 2007

In Sjögren's syndrome, salivary glands are affected, resulting in a diminished salivary flow. In the present study, the protein composition, sialic acid content and the amounts of calcium and phosphate of stimulated whole saliva from 43 patients with Sjögren's syndrome, were compared with those of control saliva samples from 17 healthy subjects. The absolute concentrations of albumin, cystatin C. cystatin S. total IgA and total protein, but not amylase, were increased significantly in both primary and secondary Sjögren's syndrome. The output/min of total protein, albumin, amylase, and IgA was, however, decreased in Sjögren patients. These results suggest that the diminished output of salivary defence factors, rather than their absolute concentrations, may be related to the oral health problems seen in Sjögren's syndrome patients.
Self‐reported occupational dermatological reactions among Danish dentists
Authors: Munksgaard Erik Christian , Hansen Erik Keith , Engen Trygve , Holm Ulla
Published: October 2007

The aims of the study were to investigate the causes and prevalences of occupational dermatological reactions among Danish dentists. Questionnaires and telephone interviews with Danish dentists revealed that 37.8% reported skin reactions. In 27.2% of the cases the reactions were related to occupation, occurring with a point prevalence of 9.6%, and with a 1‐yr period prevalence of 21.4%. The main causes were hand washing/soaps, latex gloves and (di)methacrylate‐containing materials occurring at point prevalences of 7.1%, 1.3% and 1.7%, respectively. In addition, several other causes were reported, each occurring at relatively low frequency. Diagnosed allergic latex eczema was reported by 0.6%. but the frequency might be more than 2%, estimated on basis of reported symptoms. Allergic eczema caused by (di)methacrylate‐containing materials was diagnosed among 0.7%, but estimated by the description of symptoms to be nearly 2%. The results urge for developing safer materials for dental use.