bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of monoclonal antibodies against murine dental papilla
Authors: VAINIO SEPPO , LEHTONEN EERO , KAARTINEN MATTI , THESLEFF IRMA
Published: October 2007

Abstract – The mesenchymal component of the embryonic tooth, the dental papilla, shows unique cellular behavior. Only the dental papilla cells are capable of differentiating into odontoblasts. The dental papilla also directs the morphogenesis of the tooth. Our aim is to develop suitable markers for further studies on the molecular mechanisms behind the determination and differentiation of the dental mesenchymal cells. We have produced monoclonal antibodies against this embryonal cell population. Altogether 1114 enzymatically separated mesenchymes from dissected molar tooth germs of 17‐day‐old mouse embryos were fixed in paraformaldehyde (PFA) and sonicated in saline. A rat was immunized and hybridomas were produced by standard methods. The supernatants were screened by immunohistology, using both frozen sections and sections of PFA‐fixed paraffin‐embedded mouse molar teeth. Altogether, 19 wells produced antibodies reacting with dental tissues. One monoclonal antibody recognizes a 67 000 dalton intracellular antigen enriched in secretory odontoblasts and ameloblasts. The antigen is also found in osteoblasts and chondrocytes in the developing jaw, and in some cultured murine cells. The method described here appears to be successful for generating and screening monoclonal antibodies against the dental papilla.
Distribution of Langerhans cells in clinically healthy human gingival epithelium with special emphasis on junctional epithelium
Authors: JUHL M. , STOLTZE K. , REIBEL J.
Published: October 2007

Abstract – Twenty‐one biopsies of clinically healthy marginal gingiva from children, who performed conventional oral hygiene but received no additional professional prophylaxis, were studied in order to obtain information on distribution and density of Langerhans cells (LC) in the oral gingival epithelium (OGE), the sulcular epithelium (SE) and the junctional epithelium (JE). A simple freeze‐separation technique was found to create acceptable histomorphology of JE in specimens obtained adherent to teeth, while partially and non‐adherent ones were rejected. The majority of LC in OGE, were highly dendritic and stained intensively with OKT6 monoclonal antibodies. The distribution was network‐like with a density of 21.0± 3.2 LC/0.1 mm2 crosssectional epithelial area. A similar although less dense distribution was found in SE (8.6 ± 3.0 LG/0.1 mm2). These observations, confirm previous findings. In JE 2 groups of LC were identified: 1) Weakly stained LC with very few and short dendrites distributed in a scattered way (2.8± 1.4 LC/0.1 mm2) in the apical three‐fourths of JE in most specimens. Present evidence suggests that these cells might be immature cells of Langerhans lineage. 2) Clusters of LC (9.4 ± 2.9 LC/0.1 mm2) with dendrites of moderate lengths and numbers and a varied fluorescence intensity; they were found in a few specimens in the coronal one‐fourth of JE and at the border zone to SE. Such clusters might represent genuine variation in the distribution of LC or reactions to initial/ early plaque formation.
Antiplaque effects and mode of action of a combination of zinc citrate and a nonionic antimicrobial agent
Authors: SAXTON CHARLES A. , SVATUN BJARNE , LLOYD ANN M.
Published: October 2007

Abstract – The effect upon plaque growth of adding a nonionic antimicrobial agent, triclosan, to a dentifrice containing zinc citrate was established in short‐term in vivo studies. Plaque regrowth was inhibited by brushing with dentifrices which contained either zinc citrate or triclosan. When both were combined in the same dentifrice, the inhibition of overnight plaque regrowth was significantly greater. In two 4‐day non‐brushing studies, the dentifrices containing both zinc citrate and triclosan were applied either undiluted by the use of a cap splint or as 23% suspensions in water. Both methods resulted in significant reductions in plaque accumulation, with the greater activity being observed for the undiluted application of the dentifrice. Analysis of results of the overnight plaque studies for individual teeth revealed that the two agents had a complementary inhibitory action on plaque regrowth, zinc citrate being more effective on existing plaque whereas triclosan inhibited plaque formation on clean surfaces. The dentifrice containing both agents was effective against both existing plaque and new plaque formation. It is concluded that the addition of triclosan to a dentifrice containing zinc citrate improves its antiplaque potential.
Adhesion of Streptococcus rattus and Streptococcus mutans to metal surfaces
Authors: BRANTING CHRISTINA , ODÉN AGNETA , WIATR‐ADAMCZAK EWA , LINDER LARS E. , SUND MARIE‐LOUISE
Published: October 2007

Abstract – The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6‐3H)thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria, Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26–45% of that observed in the presence of equimolar sucrose. Sucrose‐dependent stimulation of adhesion seemed to be due to increased cell‐to‐cell adhesion capacity. Isolated radiolabeled water‐insoluble and watersoluble polysaccharides produced from sucrose by S. rattus BHT were not adsorbed to the metal surfaces.
Desquamative gingivitis responding to treatment with tetracycline: a pilot study
Authors: LIND P. O. , HURLEN B.
Published: October 2007

Abstract – We experienced remarkable regression of clinical signs and symptoms in three patients suffering from desquamative gingivitis, after treatment with 100 mg doxycycline monohydrate daily for 8 wk. The possible role of plaque substances as etiologic factors in the development or maintenance of desquamative gingivitis is postulated.
Effect of postponed polishing on marginal adaptation of resin used with dentin‐bonding agent
Authors: HANSEN ERIK KEITH , ASMUSSEN ERIK
Published: October 2007

Abstract – Dentin cavities, prepared in extracted human teeth, were treated with two different dentin‐bonding agents and filled with a light‐activated microfilled resin. The maximum width of the contraction gap (MG) and the extent of the gap (GP) were then measured, using a light microscope, approximately 0.1 mm below the original free surface of the filling. The contraction gap was measured 30 s, 10 min or 60 min, and remeasured 65 min, after stop of irradiation. A positive correlation was found between the two variables, MG and GP. The product of MG and GP was chosen as basis for the statistical analyses. This “marginal index” was significantly reduced when polishing of the marginal area was postponed for 10 min with one of the dentinbonding agents and for 60 min with the other. Even though the improvement in marginal adaptation was statistically significant, this improvement was considered clinically irrelevant, It is concluded that polishing of the marginal area should not be done before the hygroscopic expansion of the resin restoration has closed the contraction gap.
Characterization of human salivary β‐N‐acetyl‐ D‐glucosaminidase (NAGase)
Authors: FOUDA NASSER EL‐TOUKHY , SÖDER PER‐ÖSTEN , OLSSON MARIE‐LOUISE
Published: October 2007

Abstract – NAGase activity was studied in mixed whole, parotid, and submandibular saliva. The maximum activity of NAGase was found to be at pH 5.0. NAGase activity varied considerably among the subjects. The data indicated that a large portion of NAGase activity originates from oral microorganisms. NAGase activity was greatly reduced after heating for 45 min at 50 °C. The residual activity after storage at – 20°C was higher than the original activity. The enzyme activity was markedly diminished after the addition of Sn++ and Ag+ ions, while no activity was detected after the addition of Hg+ ion.
Transmission electron microscopic study of giant tubules in bovine dentin
Authors: DYNGELAND TROND
Published: October 2007

Abstract – Giant tubules in the axiomesiodistally extended incisal dentin of unerupted permanent bovine incisors from 1/2‐11/2‐yr‐old calves were studied by TEM. The pulpal portion of each giant tubule contained two capillaries forming a loop incisally. The capillaries consisted of a delicate, continuous, or fenestrated endothelium and often had a pericyte coating. Cells with a rich RER, mitochondria, and Golgi apparatus dominated along and just incisal to the vessels. Extravasated erythrocytes and occasional macrophages were also seen in the latter location. It was suggested that the pulpal retraction of the giant tubule vessels during primary dentinogenesis might be the result of an intermittent sequestration of the most incisal portion of the loop, concomitant with endothelial proliferation in the pulpal portion of the capillaries. The major portion of the giant tubules, incisal to the vessels, contained a dense matrix of more or less axially oriented unmineralized 0.07–0.1‐um‐thick collagen fibrils and single cells showing gradually increasing degenerative and necrotic changes in an incisal direction. Longitudinal sections of the mineralized tubular walls revealed transversely cut collagen fibrils. The incisally located giant tubule origins were circumvented by dentinal tubules and contained 0.10–0.22‐um‐thick, densely packed collagen fibrils with an electron dense perifibrillar zone.
Effects of a sodium fluoride solution and a varnish with different fluoride concentrations on enamel remineralization in vitro
Authors: SEPPÄ LIISA
Published: October 2007

Abstract – To study the efficacy of sodium fluoride varnishes and a NaF solution in remineralization of enamel, 120 slabs of non‐carious human enamel enamel were presoftened for 6 h and randomly divided into six groups. The slabs were stored in synthetic saliva for 9 days, except for a daily 30‐min immersion in 0.1 M lactic acid‐NaOH buffer. During the 9‐day period, one group of the slabs received no treatment, and the rest were treated once or three times with 2.3% or 1.1% sodium fluoride varnish Duraphat, or nine times with a 0.1% NaF solution. Finally, the slabs were demineralized for 1 h, and the amount of dissolved Ca and F was determined. Microhardness of enamel was determined initially, after presoftening, after the 9‐ day period, and after the 1‐h demineralization. All fluoride treatments prevented enamel softening almost completely during the 9 days, but the control slabs softened markedly. Fluoride varnishes were more effective than NaF solution. Three applications of 2.3% Duraphat were slightly more effective than any of the other varnish treatments, but one treatment with 2.3% varnish was not more effective than treatments with 1.1% varnish. Enamel treated three times with 1.1% varnish showed the greatest acid resistance during the 1‐h demineralization. The results suggest that the efficacy of the varnish was not proportional to the fluoride concentration but rather to the number of applications. Fluoride uptake by enamel was greatest with the most concentrated varnish. Enamel solubility was not, however, directly proportional to the fluoride content of enamel.
In vitro study of the giant tubule collagen formation in bovine dentin by [3H]‐ proline incorporation
Authors: DYNGELAND TROND , KVINNSLAND STEINAR
Published: October 2007

Abstract – Unerupted permanent bovine incisors studied by routine autoradiography using radioactive proline incorporation revealed collagen formation within the giant tubules situated in the incisal dentin. A high [3H]‐proline labeling was seen within the pulpal vascularized portion of the giant tubules, as well as in association with groups of cells immediately incisal to the blood vessel loops. The incisal portion of the giant tubules showed no or insignificant [3H] ‐proline labeling.
In vitro erosion of bovine enamel caused by acidic drinks and other foodstuffs
Authors: RYTÖMAA I. , MEURMAN J. H. , KOSKINEN J. , LAAKSO T. , GHARAZI L. , TURUNEN R.
Published: October 2007

Abstract – The objective was to compare the erosive effect of some commonly used acidic drinks and milk products on a bovine tooth enamel model system. Conditions were selected to be sufficiently severe to cause erosion. Loss of material after erosion experiments was measured by recording the depth of the surface profile after repeated and prolonged exposure. Changes in the enamel surface were observed by scanning electron microscopy. The reparative mechanisms were studied by immersing test teeth in saliva, with or without (2 ppm) fluoride, after severe demineralization in the test products. According to the t‐test for paired means, cola beverages and orange beverages differed from beer, coffee with or without sugar, strawberry yoghurt, buttermilk, and carbonated mineral water at the level P0.01. Each of the last‐mentioned test products differed from sports drinks, diet cola beverages and orange juice less significantly. In addition, bathing of teeth in saliva between exposures to the test products did not influence the erosive depth. The results, based on in vitro conditions that ensured erosion, are useful for comparative purposes but cannot be directly extended to the oral cavity under normal use conditions.
Longitudinal study of electrometric sensitivity of young permanent incisors
Authors: BRANDT K. , KORTEGAARD U. , POULSEN S.
Published: October 2007

Abstract – Electrometric sensitivity of permanent maxillary central incisors was studied longitudinally in 34 children at 6‐month intervals over 2½ yr (mean age of the children at the beginning of the study: 94.6 months). Root development stages were determined from radiographs obtained at the beginning of the study, after 1 yr, and after 2½ yr. An increase in sensitivity was found over the study period, but large variations were found from child to child and even within the same child. Especially at the first examinations a few children showed very low sensitivity. Statistical analysis showed that examination number, root development and side of the mouth (right or left central incisor) all were statistically significantly related to sensitivity. Statistically significant differences were also found between the individuals.
Humoral leukocyte adherence inhibition response in patients with oral cancer
Authors: BECHER RUNE , KOTLAR HANS K. , SANNER TORE
Published: October 2007

Abstract – Antitumor immunity was assessed in a group of 10 patients suffering from squamous cell carcinoma of the oral cavity using the humoral leukocyte adherence inhibition assay (H‐LAI). A tumor extract from a person with cancer of the tongue was used as antigen. Sera from five patients with carcinoma of the tongue were all positive in the test. Of the other five patients, three had cancer of the lips while in two patients the type was unspecified. All patients except one with cancer of the lips gave a positive response in the test. Thus, of the 10 patients with carcinoma of the oral cavity, nine responded. Among nine controls, one person gave a positive response.
Recurrence of angular cheilitis
Authors: ÖHMAN SVEN‐CHRISTER , JONTELL MATS , DAHLEN GUNNAR
Published: October 2007

Abstract – The incidence of recurrence of angular cheilitis following a successful antimicrobial treatment was studied in 48 patients. Clinical assessments including a microbial examination were carried out 8 months and 5 yr after termination of treatment. Eighty percent of the patients reported recurrence of their angular cheilitis on one or more occasions during the observation period. Patients with cutaneous disorders associated with dry skin or intraoral leukoplakia had an increased incidence of recrudescence. Neither the presence of denture stomatitis nor the type of microorganisms isolated from the original lesions of angular cheilitis, i.e. Candida albicans and/or Staphylococcus aureus, were associated with the number of recurrences. The present observations indicate that treatment of the majority of patients with angular cheilitis should be considered in a longer perspective than previously supposed, due to the short lasting therapeutic effects of the antimicrobial therapy.
Familial study of fissured tongue
Authors: KULLAA‐MIKKONEN ARJA
Published: October 2007

Abstract – Clinical and genetic characteristics of histologically defined fissured tongue were examined in a familial study. Fifteen probands with fissured tongue and four probands with geographic tongue were selected from earlier studies. In addition, 12 probands. with tongue fissuring, but without changes of papillary structure, were included. The total sample consisted of 31 families; the number of family members examined was 185 (93 men, 92 women), and the mean age of the subjects was 20 yr (range 1–78). Diagnosis of tongue form was emphasized, and this study describes an in vivo method of stereomicroscopy for examining the dorsum of the tongue. According to genetic analysis, fissured tongue with smooth‐surfaced papillae was transmitted as a dominant characteristic with incomplete penetrance and was preceded by geographic tongue. The severity of fissured tongue changed with increasing age. Tongue fissuring with normal‐appearing filiform papillae was not familial and was not associated with geographic tongue. Fissuring with normal papillary structure should be considered as variations of normal anatomy, whereas fissured tongue and geographic tongue are a clinical and etiological disease entity.
Corrosion behavior and microhardness of three amalgams
Authors: PATSURAKOS AJIS , MOBERG LARS‐ERIK
Published: October 2007

Abstract – The marginal microhardness of three different types of amalgam was tested after 2 months' immersion in an aqueous solution of NaCl (85 mM) and phosphates (Na2HPO4 100 mM and NaH2PO4 100 mM). Amalgams immersed in distilled water were used as controls. The microhardness tests were conducted at a distance of 50 μm from the margins and at the bulk of each specimen. The solutions were analyzed for Sn, Cu, Zn, Ag, and Hg by means of atomic absorption spectrophotometry (AAS). A statistically significant reduction in the marginal microhardness after immersion in the test solution was found for the conventional and the high‐Cu single composition amalgam but not for the high‐Cu blended amalgam. SEM‐examination of cross‐sections of the amalgams revealed small areas of subsurface grain boundary corrosion, no deeper than 10 μm for all the amalgams. The SEM‐examination of the specimens and AAS analysis of the solutions indicated that the reduction in marginal microhardness was attributed mainly to corrosion of the Cu‐rich phases for the high‐Cu single composition amalgam and to corrosion of the γ2 phase for the conventional amalgam. The phosphates reduced the corrosion of the amalgams in the presence of NaCl. It is concluded that the marginal strength of dental amalgams in a corrosive environment is largely dependent upon their corrosion resistance.
Caries experience in urban Tanzanian children 1973–84
Authors: MOSHA HIASINTI JOSEPH , FEJERSKOV OLE , LANGEBAEK JÖRGEN , THYLSTRUP ANDERS , BAELUM VIBEKE , MANJI FIROZE
Published: October 2007

Abstract – In 1973 and 1984 the caries status of 624 and 394 children, respectively, was recorded in an urban area of northern Tanzania where the water fluoride content was 2.0–3.5 ppm. Although slightly different scoring criteria were used, the data showed very low levels of caries, and little evidence of increases in caries experience over the 10‐yr period. The distribution of caries lesions was markedly skewed, such that a minority of individuals accounted for most of the caries. The levels of caries were low by international standards and equivalent to those found in children from low fluoride areas of Tanzania.
Effect of copper fluoride and copper sulfate on dental plaque, Streptococcus mutans and caries in hamsters
Authors: MALTZ MARISA , EMILSON CLAES‐GÖRAN
Published: October 2007

Abstract – Topical applications of 10 mM CuF2, 10 mM CuSO4, or 20 mM NaF solutions were performed twice a day in hamsters infected with S. mutans and maintained on a high sucrose diet. Animals receiving the copper compounds exhibited lower plaque scores than control animals or animals treated with the NaF solution. The group receiving the CuF2 solution showed a lower number of S. mutans and a higher caries reduction than the groups treated with NaF or the non‐fluoride compound CuSO4.
Dental age and asymmetry in the formation of mandibular teeth in twins concordant or discordant for oral clefts
Authors: NYSTRÖM MARJATTA , RANTA REIJO
Published: October 2007

Abstract – The aims of this investigation were: 1) to study the effects of zygosity and the type of cleft on dental age in pairs of twins concordant or discordant for oral clefts, 2) to compare dental age in the twins with that in a population of normal Finnish children, and 3) to study asymmetry in the formation of mandibular teeth with regard to zygosity and the type of cleft. Twenty‐two pairs of twins (8 mono‐ and 14 dizygotic) and one set of monozygotic triplets concordant or discordant for cleft lip (CL), cleft palate (CP), or both (CLP) were investigated. Four of eight mono‐ and 12 of 14 dizygotic pairs were discordant for clefts. An orthopantomogram of both twins was taken on the same day. In 7 of the 8 monozygotic (88%) and in 4 of the 14 dizygotic (29%) pairs, the dental age was the same in both twins. Of the 12 pairs discordant for clefts, the dental age of the twin with cleft was delayed in 5, advanced in 3, and the same in 4 compared with that of the twin without a cleft. The means of chronologic age and dental age were counted separately for the cleft subgroups and the non‐cleft (NONC) group. The dental age was advanced in the CL twins and in the NONC twins, and was the same as chronologic age in the CP twins, but it was delayed in the CLP twins. Asymmetric formation of the 14 mandibular teeth (mostly the second premolars) was encountered in 3 of 8 CLP, in 3 of 18 CP, in 1 of 16 NONC, and in none of 5 CL children. The great similarity in tooth formation among the monozygotic twins indicates strong genetic control of dental maturation in twins concordant and also discordant for cleft.
Effect of fluoride addition on ionized calcium in salivary sediment and in saliva
Authors: LAGERLÖF FOLKE , EKSTRAND JAN , RÖLLA GUNNAR
Published: October 2007

Abstract – Fluoride was added in increments to pooled whole saliva. The ionized calcium concentration was determined in the saliva and the salivary sediment after centrifugation. The maxima of the ion product with respect to calcium fluoride were for salivary sediment and saliva found at 15 mmol/l and 2.5 mmol/l of fluoride, respectively. The study indicated that calcium fluoride may precipitate in the plaque matrix during and after topical application of fluoride.
Chemotactic response of neutrophil polymorphonuclear leukocytes in juvenile periodontitis measured by the Leading Front method
Authors: PEDERSEN MARIA MALLING
Published: October 2007

Abstract – Previous studies have implied that chemotaxis defects, of neutrophil polymorphonuclear leukocytes (PMNs) can be found in approximately 75% of patients with juvenile periodontitis (JP). In the present study, the Leading Front (LF) method was used to study whether the chemotactic response of PMNs from JP‐patients differed from that of adult periodontitis (AP) patients and periodontally healthy control individuals (C). Sixteen JP‐patients, 21 AP‐patients, and 13 C‐individuals were studied. PMNs from each individual, and from a daily reference person were tested against three chemoattractants (N‐f‐Met‐Leu‐Phe (FMLP), casein (CA), bacterial chemotactic factor (BCF)) and a neutral buffer (Gey's solution (GEY)). Regardless of the test solution a greater difference among individuals could be observed in the JP‐group than in the other groups. Apart from this, there were no differences among the groups as regards CA, BCF, and GEY. However, with FMLP, the PMNs of the JP‐group had a significantly greater migration distance as compared to the other groups. This finding can probably be ascribed to the fact that the LF method detects other aspects of the PMN response than do the methods used for earlier studies of JP. The finding, in this study, of an enhanced PMN response in JP as regards FMLP may be a reflection of the presence of a non‐uniform PMN population whose composition in JP differs from that of the other groups.
Tissue distribution of epimucosally applied 3H DNFB: an autoradiographic study
Authors: WARFVINGE GUNNAR , LARSSON ÅKE
Published: October 2007

Abstract – The distribution of 3H‐labeled 2,4‐dinitrofluorobenzene (DNFB) has been autoradiographically investigated in buccal mucosa after topical application to sensitized or nonsensitized rats. The rats were killed between 3 min and 24 h after challenge. No significant labeling pattern differences were found between plastic embedded and frozen sections. Surface epithelium was heavily labeled and labeled cells were observed in the lamina propria shortly (3–6 min) after application. These cells were clearly dendritic. Specific accumulation of hapten in epithelial Langerhans cells (LC) could not be clearly demonstrated. The connective tissue labeling gradually diminished and at 24 h post‐elicitation, remaining label could be detected only in the epithelial surface layers.
Influence of pontic material on alveolar mucosal conditions
Authors: TOLBOE HELLE , ISIDOR FLEMMING , BUDTZ‐JÖRGENSEN EJVIND , KAABER SVEND
Published: October 2007

Abstract – The purpose of the present study was to investigate plaque accumulation and inflammatory changes in the mucosa beneath fixed bridge pontics of various materials, in patients cleaning the infrapontic space daily. Fixed bridges with a tight but non‐compressive contact to the mucosa in the pontic area and with interchangeable test specimens placed in the pontic base were constructed for five patients. During 4‐wk periods the following materials were tested: alloys with a high or a low gold content, silver‐palladium, cobalt‐chromium, nickel‐chromium and also a dental porcelain or a composite restorative resin. Between the test periods a “sanitary pontic” was used to enable recovery of the alveolar mucosa. Clinical examinations including exudate measurements demonstrated that the alveolar mucosa remained healthy irrespective of the material used when the dental floss was used regularly. The amount of plaque on the test specimens of the seven dental materials showed no consistent differences. The composition of the bacterial deposits showed no regular pattern. This investigation has demonstrated that patients maintaining a high standard of oral hygiene are able to prevent the development of inflammatory changes in the alveolar mucosa in contact with fixed bridge pontics irrespective of the pontic material used.
HIV and hepatitis B infection in an international cohort of dental hygienists
Authors: DOBLOUG JAN H. , GERNER NINA WIENCKE , HURLEN BJÖRN , BRUUN JOHAN N. , SKAUG KJELL
Published: October 2007

Abstract – The risk for dental hygienists to contract HIV and hepatitis B infection at work was studied in an international cohort of 167 dental hygienists from 13 countries. A significant proportion of the hygienists had taken care of HIV‐positive patients or patients known to be at risk for contracting HIV infection. None of the hygienists had antibodies to HIV. Five hygienists who came from or worked in high‐endemic areas for hepatitis B infection had antibodies to hepatitis B core antigen, consistent with previous infection with hepatitis B virus. The study is in agreement with previous reports on blood‐borne infections among health care workers, concluding that the risk for dental hygienists of contracting HIV and hepatitis B infection is minimal.
Surface EMG frequency dependence on force in the masseter and the anterior temporal muscles
Authors: HAGBERG CATHARINA , HAGBERG MATS
Published: October 2007

Abstract – Myoelectric power spectrum analysis was used to study isometric contractions, 10–15 s long, of the masseter muscles and the anterior temporal muscles. Surface EMG activity was recorded from these muscles for nine females while biting on a bite force transducer up to maximal effort (100% maximal voluntary contraction; MVC). The mean frequency (MF) was calculated as a single estimate of the myoelectric power spectrum. Regression analyses were made of MF versus bite force (0–100% MVC). The mean MF values of all females' masseter muscles increased up to 55–60% MVC. For the anterior temporal muscles no increase in mean MF was found above 20–25% MVC The increase in MF was possibly dependent on recruitment of type I fibers and low‐pass tissue filtering effects. The slope of regression for the force level 0–60% MVC was intraindividually steeper for the masseter muscles than for the anterior temporal muscles. A similar decrease in mean MF was found for the masseter muscles and the anterior temporal muscles for the force level 60–100% MVC The possibility of muscular fatigue was discussed.
Prediction of behavior management problems in children
Authors: HOLST ANNALENA , SCHRÖDER ULLA , EK LARS , HALLONSTEN ANNA‐LENA , CROSSNER CLAES‐GÖRAN
Published: October 2007

Abstract – The aim of the present investigation was to study non‐dental and dental background variables with a view to estimating their influence on behavior management problems by means of a structured interview and analyzing their separate and combined predictive power. The material consisted of a case group, 101 children aged 3–16 yr, referred for management problems to clinics of specialized pedodontics, and a control group, individually matched with the cases as regards age, sex, residential area, number of tooth surfaces restored, and dentist. The children or their parents were interviewed concerning background variables. Logistic regression was used for the analyses. Three non‐dental variables turned out to be statistically significant as predictors (P<0.05): problems on visiting a medical doctor, dental fear in the mother or father, and anxiety when meeting unfamiliar people. Management problems might be expected if one of these attributes is found. Four dental variables had significant predictive power: earlier problems on seeing a dentist, dislike of the dentist, not enough time to adjust to the dental situation, and fear of injection. However, none of these dental variables was found to have predictive power in 3–6‐yr‐olds, and none of them improved the predictive power of the three main non‐dental variables.
Corrosion current and pH rise around titanium coupled to dental alloys
Authors: RAVNHOLT GERT
Published: October 2007

Abstract – Corrosion reactions around titanium, usually considered biologically inert, might be provoked by coupling it galvanically with more corrodible dental alloys. Experiments in vitro simulating the conditions of a titanium dental implant or root canal post coupled to an amalgam filling, demonstrated corrosion current densities up to 31 μA/cm2 anodic pH values around the amalgam down to 2, and cathodic pH values around the titanium up to 10. The amounts of tin released by the enhanced corrosion, of amalgam might contribute measurably to the daily intake of this element; the corrosion current generated reached values known to cause taste sensations. If the buffer systems of adjacent tissues in vivo are not able to cope with the high pH generated around the titanium, local tissue damage may ensue; this relationship is liable to be overlooked, as it leaves no evidence in the form of corrosion products.
Effect of preventive measures in 50–60‐year‐olds with a high risk of dental caries
Authors: RASK PER‐INGE , EMILSON CLAES‐GÖRAN , KRASSE BO , SUNDBERG HANS
Published: October 2007

Abstract – Salivary and microbial conditions were examined in 124 50–60‐yr‐old patients attending a dental clinic of the Public Dental Health Service. They were then randomly divided into a control and a test group. Patients with low salivary secretion rate and buffer capacity and high numbers of mutans streptococci and lactobacilli in the test group received special caries preventive measures during 1 yr. In the control group all patients were given prevention according to routine procedures. The incidence of dental caries between the groups was compared. The risk patients in the control group developed 1.67 new carious lesions as compared to 0.19 in the test group. The difference was statistically significant (P<0.05). Also the numbers of mutans streptococci and lactobacilli were significantly lower in the risk patients in the test group after 1 yr compared with baseline values. After the experimental year all patients were treated according to routine procedures. Five years after the start of the study a new examination showed increased caries activity in the risk patients in the test group and the gain which had been made during the experimental year was almost lost.
Amelogenesis imperfecta – clinical manifestations in 51 families in a northern Swedish county
Authors: BÄCKMAN BIRGITTA
Published: October 2007

Abstract – The clinical manifestations of amelogenesis imperfecta (AI) were described in 165 individuals from 51 families. The inheritance pattern for AI in these families had previously been investigated, and it was hypothesized that AI probably is solely an autosomal dominant (AD) or X‐linked trait. To test this hypothesis the connection between clinical manifestation and inheritance pattern was studied. Eight different variants of AI were seen. In 33/51 families all affected individuals could be assigned to the same clinical variant. In 8/51 families those affected were assigned to different clinical variants. In the two families where an X‐linked recessive (XR) inheritance pattern was found probable, the clinical manifestation differed between women and men. Except for one variant only seen as an AD trait, and the manifestation in women in families with an X‐linked recessive inheritance pattern, no connection was found between a specific inheritance pattern and a specific clinical manifestation. Accordingly it seems likely that AI is solely an AD or X‐linked trait. The different clinical variants observed should be regarded as a varying expressivity of the gene and in the families with X‐linked inheritance probably due to lyonization. In the remaining families the modifying mechanisms are not known.
Long‐term retention of TiF4 and SnF2 after topical application to dentin in dogs
Authors: TVEIT ANNE BJÖRG , KLINGE BJÖRN , TÖTDAL BAARD , SELVIG KNUT A.
Published: October 2007

Abstract – As part of an evaluation of the potential of topical application of TiF4 in the prevention or arrest of root caries, the longevity of the titanium‐rich glaze and the long‐term retention of titanium and fluoride in exposed dentin surfaces were examined in dogs. For comparison, the effect of fluoride in combination with another cation, tin, was studied as well. Facets of exposed dentin were prepared in two beagles and treated for 1 or 4 min with either a TiF4 or an SnF2 solution (1.1 M F, native pH). After 3, 7, or 21 wk, the experimental surfaces were analyzed for fluoride, titanium, tin, and calcium using an electron microprobe. Dentin surfaces treated with TiF4 for 1 min showed fluoride concentrations ranging from less than 0.15% to 1.03%, while those treated for 4 min with SnF2 showed values from 0.22% to 1.28%. The calcium analyses revealed partial surface demineralization in one half of the SnF2‐treated specimens, while this was a rare finding in the TiF4 group. The findings show that a brief application of TiF4 to exposed dentin results in approximately the same increase in fluoride content as a 4‐min application of SnF2, with, however, less surface demineralization. In addition, the presence of a surface glaze may impart an added benefit to the use of TiF4 as a topical agent in the prevention of root caries.
Inhibition of plaque formation and plaque acidogenicity by zinc and chlorhexidine combinations
Authors: GIERTSEN ELIN , SCHEIE ANNE AAMDAL , RÖLLA GUNNAR
Published: October 2007

Abstract – Zinc ions and chlorhexidine (CH) were found to exhibit a synergistic inhibitory effect on in vitro growth of S. sobrinus OMZ 176 and of S. sanguis 10556. A clinical mouthrinsing experiment was performed in a group of 10 volunteers to assess the plaque‐inhibiting capacity of this combination. Sucrose enhanced plaque accumulations were assessed (Plaque Index, Silness & Löe) after 4 days of twice daily mouthrinses with 10 ml aqueous solutions of either 10.0 mM zinc or 0.55 mM CH, or with a combination of zinc ions and CH, during which period no mechanical toothcleaning was performed. The Zn–CH combination showed improved inhibition properties compared to the individual agents. The effects on plaque acidogenicity of 8.0 mM zinc, 0.44 mM CH, and of zinc and CH in combination were also assessed in a test panel of five volunteers. The Zn–CH combination inhibited acid production by dental plaque significantly (P< 0.05) more than the individual agents 1 h 30 min after a single rinse.
Adhesion to dentin by means of Gluma resin
Authors: ASMUSSEN ERIK , ANTONUCCI JOSEPH M. , BOWEN RAFAEL L.
Published: October 2007

Abstract – In its present version, the Gluma system for bonding restorative resin to dentin involves the application of an enamel bonding agent prior to the composite resin. Conceivably, pretreating the dentin with solutions of amino acids, and incorporating camphorquinone and selected methacrylic monomers into the Gluma adhesive would nullify the need for the enamel bonding agent. A bond strength to dentin of 13.4 MPa was obtained in the control experiment. Using a solution of pyruvic acid and glycine as pretreatment, and an optimized adhesive mixture containing glutaraldehyde, HEMA, BIS‐GMA, camphorquinone, and water, bond strengths to dentin of 14.5 MPa and to enamel of 23.3 MPa were obtained. Thus, the new Gluma bonding system gave acceptable bond strengths without the prior application of enamel bonding agents.
Effect of tetracycline and SnF2 on root resorption in replanted incisors in dogs
Authors: BJORVATN KJELL , SELVIG KNUT A. , KLINGE BJÖRN
Published: October 2007

Abstract— The present study was made to assess the effect of applying SnF2, tetracycline, or both, to root surfaces of extracted teeth prior to replantation. In five young adult beagles, a total of 18 mandibular incisors were extracted, bench dried for 45 min, and reimplanted in their respective sockets either after no further treatment or following treatment with 1 % doxycycline HC1 for 5 min, 1% SnF2 for 5 min, or 1% SnF2 followed by 1% doxycycline HG1. After 4 wk of healing, the relative frequency of root resorption (surface resorption, inflammatory resorption and replacement resorption) was approximately 27% of the root surface in bench‐dried as well as in doxycycline‐treated specimens. By contrast, SnF2‐treated and SnF2+ doxycycline‐treated teeth showed less than 1% resorption. In the latter two specimen groups an inflammatory reaction in the periodontal ligament without resorption occurred with a frequency of 38.3% and 11.1%, respectively. The results indicate that application of SnF2 to the root surface prior to replantation effectively reduces resorptive processes during the first postoperative weeks. By subsequently treating the root surface with tetracycline, the adverse effect of SnF2 on periodontal connective tissue repair may be reduced.
Effect of a high dose of fluoride on resorbing osteoclasts in vivo
Authors: LINDSKOG SVEN , FLORES MYRA E. , LILJA EVA , HAMMARSTRÖM LARS
Published: October 2007

Abstract— Histomorphometric analysis of osteoclasts resorbing bone above the erupting first rat molar tooth germ was made at 1, 2, 6, 24, and 48 h following systemic administration of a single high dose of sodium fluoride. Compared to the number of osteoclasts in control rats, a significant reduction was observed in the number of actively resorbing osteoclasts in fluoride‐injected rats at 2 and 6 h after dose administration, after which a gradual increase to control levels was observed. A locally increased number of inactive osteoclasts, not attached to bone surfaces, accompanied the reduced number of active osteoclasts.
The human gingival indeterminate cell revisited
Authors: WARFVINGE KARIN
Published: October 2007

Abstract— Electron microscopic examination of over 100 dendritic cells in human keratinized gingiva has shown that the indeterminate cells are not a separate cell type. This approach disclosed the sources of error which have led to the commonly held, but erroneous, view that there exist numerous indeterminate cells in this epithelium. Two interesting differences were found between gingival and epidermal Langerhans cells. The number of Birbeck granules in the former cells can be extremely low while they occur frequently in the epidermal cells, and granules in their formative stage are commonplace in the gingival cells but rare in the epidermal cells.
Gingival fluid, beta2‐microglobulin and protein levels as indicators of periodontal disease
Authors: SYRJÄNEN STINA M. , ALAKUIJALA PEKKA , MARKKANEN SEPPO O. , MARKKANEN HELENA
Published: October 2007

Abstract— β2‐microglobulin (β2‐m), lysozyme and protein concentrations in gingival fluid were analyzed in 19 patients with severe periodontitis and in 19 controls devoid of any clinical signs of inflammation. A significant increase of the total protein and β2‐m levels was found in periodontal subjects. In contrast, lysozyme concentration did not reflect the inflammatory status of the periodontium. Statistical analyses showed significant correlations between β2‐m and protein concentrations in both groups. Furthermore, the values obtained by Periotron 600 closely correlated with the protein and β2‐m contents, indicating that this method is a reliable aid in assessment of the quantity and quality of crevicular exudate and thus the severity of periodontal disease.
Uptake and expulsion of 14C‐xylitol by xylitol‐cultured Streptococcus mutans ATCC 25175 in vitro
Authors: SÖDERLING EVA , PIHLANTO‐LEPPÄLÄ ANNE
Published: October 2007

Abstract— The effect of successive cultivations in the presence of 6% xylitol on the uptake and expulsion of 14C‐xylitol was studied using the cells of Streptococcus mutans 25175. Three sequential cultivations did not alter the growth inhibition percentage (approximately 50%) observed in the presence of 6% xylitol. The 14C‐xylitol uptake experiments performed with growing and resting cells showed that both the uptake and the expulsion of xylitol were enhanced by xylitol‐culturing. Both xylitol‐cultured and resting control cells contained only one major labeled compound which was identified as 14C‐xylitol 5‐phosphate. The label subsequently was expelled from the cells as 14C‐xylitol. These results indicate that S. mutans possesses an intracelluiar xylitol cycle and this cycle is regulated by adding xylitol to the growth medium.
Effects of the thiazide diuretic bendrofhimethiazide on salivary flow rate and composition
Authors: NEDERFORS TOMMY , TWETMAN SVANTE , DAHLÖF CARL
Published: October 2007

Abstract— Thiazide diuretics are among the first‐line alternatives in the treatment of primary hypertension. The effects of thiazide treatment on salivary production are, however, little studied and the results so far available are not decisive. The aim of the present study was to evaluate and compare salivary flow rate and composition during treatment with the thiazide diuretic bendroflumethiazide in a low dose (2.5 mg o.d.) and placebo. The study was performed with a randomized, double‐blind, cross‐over design (2 × 2 wk) in 34 healthy volunteers. The treatment periods were separated by a wash‐out period of 2 wk. Resting and stimulated whole saliva was sampled three times daily on scheduled days during the treatment periods. Flow rate was assessed for resting saliva, whereas flow rate, pH, buffer capacity, amount of total proteins and concentrations of sodium, potassium, calcium, phosphate and magnesium were measured for stimulated whole saliva. No effect of bendroflumethiazide on the resting salivary flow rate could be detected, while the stimulated flow rate was significantly reduced by about 10% during the thiazide treatment. The total sodium output was significantly decreased by approximately 30%, without any detectable change in total potassium output. All other variables of stimulated whole saliva studied were not different from placebo. It is concluded that treatment with bendroflumethiazide in a low dose significantly reduces the stimulated whole salivary flow rate and total sodium output in healthy volunteers.
Spray dispensing of antiseptics is effective for hand disinfection
Authors: MEURMAN J. H. , PENTTI P. , SUHONEN J. , KOSKELA M.
Published: October 2007

Abstract— The effectiveness of three hand antiseptics administered using a spray dispenser (Nebucid 840) was studied together with that of conventional hand disinfection. The tests were carried out by a group of 20 dental students. To obtain baseline samples, the subjects washed their hands with unmedicated Sterisol liquid soap under running water for 30s and dried them on sterile‐packed paper towels. Microbiologic samples were taken from fingerprints pressed gently onto blood agar plates, which were then incubated aerobically and analyzed. The hand disinfection efficacy of 3 ml Isosept solution rubbed onto the hands for 30 s, followed by air drying for 60 s, was studied as a conventional control method. Dermocol, HD 410, and Hibisol antiseptics were sprayed onto the subjects' hands for 3 s using the automatic dispenser, after which the hands were gently rubbed for 30 s and air‐dried for 60 s, before fingerprint contact sampling. All the tests were performed three times, with a minimum of 3 days between the series. The results showed Hibisol applied with the spray dispenser to be significantly more effective in reducing bacterial growth than the other methods. No growth was observed on 51 plates out of 60, while bacterial growth was observed in 29 cases out of 60 in the Isosept series. In most cases the spray‐dispensed antiseptics proved to be more efficient than the conventional hand antiseptic. All the antiseptics were significantly more effective than the liquid soap.
Immediate electromyographic response in masseter and temporal muscles to bite plates and stabilization splints
Authors: DAHLSTRÖM LARS , HARALDSON TORGNY
Published: October 2007

Abstract— The immediate influence on masticatory muscle activity of bite plates and stabilization splints was investigated in control subjects and patients with craniomandibular disorders. Electromyographic surface recordings were performed from the masseter and temporal muscles bilaterally with and without the appliances in situ. In the rest position, no significant change in average activity was registered in any muscle with either appliance. Activity during maximal biting on stabilization splints was not different from that without the appliance while bite plates caused a decrease in activity in both muscles in both groups. The reduced maximal activity was probably due to the smaller number and exclusively anterior positioned occlusal contacts on the bite plate.