bluuebunny/crossref_metadata_2025 huggingface dataset:
Electronmicroscopic study of mineralization in induced heterotopic bone formation in guinea pigs
Authors: NILSEN RUNE
Published: October 2007

Abstract –

Mineralization of heterotopic bone was studied in a bone induction model using allogenic demineralized dentin implanted in the abdominal wall of guinea pigs. There was a high yield of newly formed osteoid and bone as well as some cartilage together with areas of resorption of the dentin, and fibroblast proliferation. The osteoid contained many matrix vesicles II and less of lysosome‐like type I vesicles. Early cartilage formation had more type I vesicles. The implanted dentin contained no matrix vesicles. The first signs of mineralization occurred mainly as irregular clusters of mineral crystals in the matrix close to the surface of collagen fibrils, Crystal‐like figures were also found inside some type II matrix vesicles, although most of these vesicles in the mineralization zone had no crystals. The type I vesicles of both bone and cartilage exhibited often crystals near the outer membrane. The mineralizing bone showed a reduction in the size and number of proteoglycan particles. Remineralization of the implanted dentin was also often found and the mineralization pattern resembled the mineralization of bone except for the absence of matrix vesicles. Electron diffraction of selected areas showed that the crystals in the new bone and the mineralized dentin were hydroxyapatite.
Correlation between tensile and bond strength of composite resins
Authors: ZIDAN OMAR , ASMUSSEN ERIK , JØRGENSEN KNUD DREYER
Published: October 2007

Abstract –

The purpose of the present work was to measure the bond strength of five composite resins (two microfilled and three conventional) to human etched enamel and to correlate the findings with previously published results on the tensile strength of the same resins. The two microfilled composites showed a significantly lower bond strength than the three conventional products. The coefficient of correlation between tensile and bond strength was 0.74.
Dentition on Umm an‐Nar (Trucial Oman), 2500 B.C.
Authors: HØJGAARD KAREN
Published: October 2007

Abstract –

Teeth and jaws excavated from three burial cairns on the island of Umm an‐Nar outside Abu Dhabi were examined. Dating: 2500 B.C. The number of individuals buried was estimated from the dentitions. In spite of the bad condition of the sparse material an attempt was made to give an impression of non‐metric and metric traits of the teeth. The teeth showed Caucasoid but no Mongoloid traits. They were small, worn at an early age, with abundant calculus, multiple fractures but no carious lesions, The percentages of agenesis of third molars in the three graves were equal. Alveoloclasia appeared frequently. The population would seem to be hunters and fishermen rather than agriculturists.
Hypodontia of permanent teeth in Danish schoolchildren
Authors: RØLLING STEEN
Published: October 2007

Abstract –

Hypodontia, congenitally missing teeth, is one of the conditions recorded during systematic orthodontic screening of groups of children attending a community child dental health service. The present investigation reports the prevalence of hypodontia in 3325 9–10‐year‐old children in the 3rd schoolgrade examined with an orthopantornographic radiograph. The prevalence of children with hypodontia was found to be 7.8%. Fifty percent of these children were missing only one tooth while 85% were missing either one or two teeth. More teeth were missing in the mandible than in the maxilla. The teeth most frequently missing were the second premolars, representing 67% of the congenitally missing teeth. Symmetrical hypodontia of second premolars occurred approximately twice as often in girls as in boys. Though more teeth were congenitally missing in girls than in boys, no difference could be seen in the prevalence of hypodontia in boys (7.7%) and girls (7.8%).
Appearance of chemically treated root canal walls in the scanning electron microscope
Authors: KOSKINEN KARI P. , MEURMAN JUKKA H. , STENVALL HANNELE
Published: October 2007

Abstract –

The dissolving effects of seven endodontic solutions on unprepared root canal walls of young intact human premolars were evaluated with the scanning electron microscope. After incubation at 37°C in distilled water or isotonic saline for 10 min the predentinal surfaces showed no changes as compared with untreated controls. The demineralizers Decal® and Largal Ultra® had little effect on the organic tissues but caused some decalcification where mineralized dentin was exposed. Nelex® caused concentration‐dependent coagulation of the residual pulp tissue, making typical ring structures on the surfaces. Sodium hypochlorite at 2.5% and 5.0% dissolved most of the predentin, exposing the globular appearance of the mineralizing front. Salvizol® produced small globules on otherwise intact surfaces. Dissolution of both the organic and inorganic tissue of the root canal wall would require the combined use of two of the solutions studied.
A model for experimental endodontics by transplanting human dental roots subcutaneously to rats
Authors: HØRSTED P. , FEJERSKOV O. , JOHANNESEN G.
Published: October 2007

Abstract –

In 35 roots from extracted human teeth the pulp tissue was removed and the specimens autoclaved. before being transplanted subcutaneously to rats. The animals were sacrificed 7, 14, 21, 90 and 140 d after transplantation and the skin and subcutaneous tissue containing the transplants were prepared for histologic examination. The human roots were well tolerated by the rats with a fibrillar connective tissue capsule surrounding the specimens. In the 90‐d and 140‐d groups a few root surfaces exhibited small resorption lacunae. The empty root canals became slowly occupied by a maturing granulation tissue occasionally containing foci of lymphocytes. After 140 d the canal tissue was still highly vascular with multinuclear giant cells occasionally located along the dentin walls but no internal resorption was recorded. It is concluded that this model may be useful for systematic testing of root filling materials concomitant with human studies.
Effect of nystatin in the treatment of denture stomatitis
Authors: BERGENDAL TOM , ISACSSON GÖRAN
Published: October 2007

Abstract –

The effect of nystatin treatment on denture stomatitis subclassified as generalized simple inflammation and inflammatory papillary hyperplasia has been studied. Twenty‐four patients were carefully instructed to apply a thin layer of nystatin dusting powder on the fitting surface of the maxillary denture three times a day for 14 d. Different parameters were studied on three occasions; at the beginning of experiment and after 14 and 28 d. An untreated group of 24 patients with the same types of denture stomatitis served as control. The effect of treatment was. evaluated by changes in the clinical erythema, the yeast colonization obtained by mycologic sampling on the palatal mucosa and on the denture base, and changes in the histologic picture of the mucosa obtained by biopsy. Subepithelial inflammation, leukocyte penetration, edema and thickness of the epithelium were histologic parameters. After 14 d of treatment the experimental group compared with the control group showed a statistically significant decrease in palatal erythema and in the amount of yeast colonies. No significant changes were found microscopically. Twenty‐eight days after start, i.e. 14 d after withdrawal of the nystatin, there still was a statistically significant improvement of the palatal erythema in the experimental group compared with the controls. However, no patient was totally cured. There were no significant changes in the number of yeast colonies and the histologic parameters.
Variable experession of familial hypodontia in monozygotic triplets
Authors: MÖLLER PÅL , RUUD ARNE FREDRIK , KVIEN TORE KRISTAN
Published: October 2007

Abstract— Hypodontia was demonstrated in a mother and her monozygotic triplets. The triplets and their mother exhibited considerable variation in the expression of the trait. The variation within the Triplets must be due to non‐genetic factors.
In vivo recalcification of dentin demineralized by citric acid
Authors: TVEIT ANNE BJÖRG , SELVIG KNUT A.
Published: October 2007

Abstract— Acid‐treatment of root surfaces as an adjunct to pcriodontal reconstructive may have deleterioujs effects on that part of the root which remains in a supragingival location after healing. The peresent experiment aimed to examine whether recalcification of such root surfaces may occur. Cylindrical blocks of root dentin were prepared from 10 premolar, treated with citric acid and mounted in acrylic specimen holders which worn in the mouth continuoulsy for 14 d by two test subjects. The specimens were then sectioned and microradiographs produced. The citric acid had produced a completely demineralized surface zone in the root dentin and the subject hard tissue showed a zone of partially reduced mineral content. Following exposure to the oral cavity, the demineralized surface layer appeared unchanged in width. The subjacent zone, however, had been reduced in width in all instances when compared with control specimens from the same teeth.
Effect of cyclophosphamide on dentinogenesis in the rat incisor: fluorescence microscopic and microradiographic investigations
Authors: KOPPANG HABBA STRÖMME
Published: October 2007

Abstract— Previousy described dentin reactions to cyclophosphamide (CPhA) were studied by means of fluorescent labeling and microradiography. Ten adult rats received 20mg/kg calcein i.p. on days 0, 4,7 and 10, and 40mg/kg CPhA 30 min after the first calcein injection. Two animals served as controls. the observation time was 14 d. Fluorescence microscopy and microradiograsphy of the maxillary incisors revealed 1) Neche‐like defects in dentin starting tomineralize 1‐4 d after the CPhA administration labially, while lingually the niches developed later and were completed earlier,2) localized reduced and increased growth lingually,3) continuous but reduced apposition of a hyponmineralized dentin in the niches, and 4) niche osteodentin produced by pulp cells.
Human Buccal mucosa transplants in nude mice
Authors: HOLMSTRUP P. , STOLTZE K. , BRETLAU P. , DABELSTEEN E.
Published: October 2007

Abstract— The development of a model to study tissue interactions in human oral mucosa in vivo utilizing transplantation of human tissue to nude mice is described. Ninety‐Six Samples of normal human Buccal mucosa were transplanted to subcutaneous sites in the flank region of nuke and were Protected from overlying cutaneous and subcutaneous tissue by polyethylene capsules or by millipore filters. Transplant recovery rates were 47% and 69%, respectively. The histologic features of the epithelium of transplanted specimens were compared to 20 biopsies of normal buccal mucosa. The epithlium of transplants maintained for 3 weeks or longer with either type of protection, maintained features essentially similar to the normal controls but was somewhat thinner.
Influence of spatulation time upon the radio‐graphic homogeneity of Adaptic Radiopaque® fillings
Authors: SEWERIN IB
Published: October 2007

Abstract— Twelve test cavities were filled with Adaptic Radiopaque by die author, varying the spatulation times from 5 s to 60 s at 5‐s intervals but using the same mixing technique. Fillings spatulated for less than 20 s appeared inhornogeneous on radiographs. 2) Twenty‐eight dentists produced 84 test fillings determining themselves their spatulation time and applying their own mixing technique. Spatulation times varied! froira 10 to 35 s. The fillings were radiographed under standardized conditions. Twenty‐five were classified as radio graphically homogeneous, 35 as partly iniiomogeneous, and 24 as inhomogeneous. Short spatulation times were correlated with a high frequency ofinhomogeiieous fillings. Only 15% of fillings spatula ted for less than 30 s were radiographically homogeneous. The observed inhomogeneities imply a risk of false positive diagnoses of secondary carious lesions.
Sensitivity of different human cell lines in the biologic evaluation of dental resin‐based restorative materials
Authors: HENSTEN‐PETTERSEN ARNE , HELGELAN KRISTEN
Published: October 2007

Abstract— Three different cell lines of human origin, i.c. human epithelica cells (NCTC 2544), and epithelial and fibroblast like cells from human gingiva, were tested for their sensitivity fo three different dental resin‐based restorative materials using four different assay techniques. The techniques applied were cell growth measurements by cell number, 53Cr‐release, Agar overlay with neutral red staining and colony formation. The ranking of teh cells according to their sensitivity ot the materials varied with the assay technique applied, with no cell line being consistently more sensitive than the others. It is also suggested that the type of medium applied could be important for the result obtained.
Levels of methylmethacrylate, formaldehyde, and asbestos in dental workroom air
Authors: BRUNE DAG , BELTESBREKKE HANS
Published: October 2007

Abstract— The levels of methymethacrylate and fromaldehyde in workroom air of a dental laboratory following finishing and polishing a pour type denture base resin have been measured. The levels of these compounds did not exceed the repective hyginic threshold limit values in the general workroom air or in breathing air close to workpice. The centent of asbestos fibers in breathing iair reliased during dismantling molds from gold casting was measured. Durtin the dismanting procedure the fiber content in the air could exceed thresholdlimit values by up to about 12 times. However, About 10 min after terminating this process the fiber content had declined to a level below the esablished requirements.
Absence of enamel kmatrix on root‐analogue surfaces of rabbit permanent incisors
Authors: GREVSTAD HANS JACOBB , SELVIG KNUT A.
Published: October 2007

Abstract – Permanent incisors from fetal New Zealand white rabbits aged 27–29 d in utero and fromoffspring of New Zealand white rabbits until the 4t d after parturition were processed for scanning electron microscopy. Macroscopic examination and measurements on standardized scanning electron micrographs revealed that the lingual surface of unerupted teeth was covered with developing enamel extending about 2.1 mm from the incisal end as evidenced by the presence of typical Tomes' pits. Such structures were not observed more apically where the lingual tooth surface appeared to be covered by cementum. The permanent incisors erupted into the oral cavity at birth and attrition was initiated within a few hours after parturition, jleading to an inverse correlation between attritional loss of tooth substance and extension of lingual enamel. The findings indicate that the enamel‐covered, linguoincisal part of the rabbit permanent incisors is not a root‐analogue surface. The results are discussed in te light of recent studies on rabbits and rodents.
Comparison of there anaerobic culture techniques and media for viable recovery of subgingival plaque bacteria
Authors: OLSEN INGAR , SOCRANSKY SIGMUND S.
Published: October 2007

Abstract – Various methods are available for viable recovery of bacteria from subgingival plaque, but theire relative efficicency is not clear. In the first experiment, with 10 patients, three anaerobic techniques (Brewer jars, chamber and roll tubes) and three agar media (trypicase soy with 5% sheep blood (TS), brucella agar with 5% blood and 0.5 ug/ml of menadione (B), and modified medium 10 with 3% blood (MM 10)), were compared. In the second experiment, with anaother 10 patients, Brewer jars were compared with a glove box, using TS. Subgingival plaque was sampled with a gas flushed broach passed through a syringe. Significance of differences in viale recoveries was determined by ANOVA. Brewer jars and chamber (aerobic plating) were comparable in efficiency, but excelled roll tubes (anaerobic inoculation). TS was better than B, but equivalent to MM 10. TS in Brewer jars (aerobic plating) matched TS in the glove box (anaerobic plating), but perforemed better than all the other procedures tested. Recoveries did not differ on pre‐and non‐prereduced plates and on commercial and laboratory, freshly made platels. Non‐evacuated jars sealed inside the box (anaerobic plating) provided lower recoveries than jars evacuated, filled and sealed outside (aerobic plating). Roll tubes benefited most by extending incubation from 7 to 14d. Commercial, non‐prereduced TS agar plates incubated in Brewer jars or a glove box are highly recommendable methods for processing of subgingival plaque.
Effect of storage in media with different ion strengths and osmolalities on human periodontal ligament cells
Authors: BLOMLÖF LEIF , OTTESKOG PER , HAMMARSTRÖM LARS
Published: October 2007

Abstract – The viability of the periodontal ligament (PDL) cells is critical for a successful healing of replanted exarticulated teeth. It is mainly dependent on the duration of the extra‐alveolar time and the storage medium. Saliva has usually been recommended as the most suitable storage medium, but recent experimental studies indicate that milk is preferable. In the present study the effect on cultured PDL cell of saliva and milk has been compared with some reference media such as tap water or saline by means of a 3H‐uridine leakage test. Storage in milk or saline was found to cause much less 3H‐uridine leakage that storage in saliva or tap water. Cells stored in milk for 60–180min showed about the same leakage as cellsstored in saline or Hanks' balanced salt solucion. Osmolality measurements showed that saliva was hypotonic, while the osmolality of milk ranged with physiological limits. When the osmolality of saliva was increased by addition of NaC1 the leakage of the stored cells decreased to the level of cells stored in 0.9% Nac1 or milk.
Distribution of blood group antigen H in hunan buccal epithelium of secretors and non‐secretors
Authors: VEDTOFTE P. , HANSEN H. E. , DABELSTEEN E.
Published: October 2007

Abstract – The distribution of blood group antigen H in human buccal epithelim was examine in 22 individuals, 16 secretors and six non‐secretors of blood group antigens in the saliva. An extract of Ulex individuals, 16 secretors and six non‐secretors of blood group antiens in the saliva. An extract of Ulex europeus was used as marker of blood group antigen H in a triple laer immunofluorsecence technique. The cell membranes of the spinous cell layer stained positively in all individuals, whereas the basal cells reacted negatively. Secretors and non‐secretors had similar distributions of blood group antigen H in the buccal epithelium. However, a significantly higher amont of blood group antigen H was found in secretors than in non‐secretors. The study indicates that an extract of Ulex europeus is a valuable marker for blood group antigen H in studying the distribution of this antigen in oral epithelium.
Description of population and progress of symptoms in a longitudinal study of temporomandibular arthropathy
Authors: RASMUSSEN OLE COLLIN
Published: October 2007

Abstract – The progress of symptoms in‐termporomandibular arthropathy can be divided into six phases. Phases 1 and 2 make up an initial stage of clicking and locking, Phase 3 and 4 an intermediare stage of temporomandibular joint pain and constriction, and Phases 5 and 6 make up a terminal stage of crepitation and constriction followed by freedom from symptoms. The abrupt replacement of clicking and locking by pain and constriction is highly characteristic and may be considered the true debut of arthropathy. During the course of arthropathy all temporomandibular joint symptoms but crepitation improve, resulting practically always in freedom from pain and most often in freedom from symptoms. Gomplere recovery is most favorable in the case of full dentures or intact natural dentition. Subject to some variation, the three stages endure 4, 1, and 1/2 year, respectively; unafleeted by age, dentition or eliciting factors. Replases of arthropathy seem unlikely whereas muscular symptoms or contralateral clicking may develop.
Follow‐up study of permanent incisors with enamel fractures as a result of an acute trauma
Authors: RAVN J.J.
Published: October 2007

Abstract – The present investigation evaluated the prognosis for vitality after and acute trauma in 2891 permanent incisors with enamel fracture as the only damage, and in 476 incisors with enamel fracture combined with other symptoms on the damaged tooth. Pulpalnecrosis developed in 57 teeth (1.7%). Acute treatment in connection with enamel fracture was only performed in half of the cases and had no importance on vitality. The combination of enamel fracture and concussion or mobility resulted in pulpal necrosis in 8.5% of cases, and cases involving both mobility and concussion meant pulpal necrosis in 14% of teeth. The findings clearly illustrated that an enamenamel fractures is an injury with an extremely favorable prognosis, and that the risk group can be narrowed to cases of combined injuries involving the supportive tissue.
Elastic (pseudoelastic) tissue in arterioles of the human and dog dental pulp
Authors: HALSM EINAR , TÖNDER KARIN J.H.
Published: October 2007

Abstract – Formalin‐fixed pulps from seven human and five dog teeth were investigated for the occurrence of vascular elastic tissue with special reference to the difference between elastin and pseudoelasuca. The latter term denotes structures which show the histochemical and fluorescence microscopic. properties of collage, but also bind the so‐called elastica stains. Hanuman aorta, and aorta, lips, tongues and gingiva from dogs served as control material. Whereas conventional elastica stains, in this stydy represented by orcinol‐new fuchsin, only differentiate elastic tissue and cikkage; a thiazine red R fluorescence method also permits differentiation between elastin memberances and pseudoelastica. Other methods for light and fluorescence microscopy verified this conclusion. Pseudoelastic fibers/memberances occurred in arterioles of both human and dog pulps, but were more frequent in the latter. The distribution of these elements in the arteiolar walls was different in the human and dog pulp. No elastin elements were observed.
Effect of chlorhexidine gel treatment on Streptococcus mutans population in human saliva and dental plaque
Authors: EMILSoN CLASES GÖURAN
Published: October 2007

Abstract – The effect of topical application of a 1% chlorhexidine gel on the population of S.mutains in dental plaque and saliva was studied in five subjects highly infected with the organism. After treatment for 5 min daily for 14 d, S. mutans was not detected in three of the subjects and counts of 700 colony‐forming units or less per ml of saliva were found in the other subjects. Reappearanceof S. mutans was slow and did not reach pretreatment level until 14 weeks or more after therapy. The proportion of S. saguis in plaque increased temporatrily after chlorhexidine treatment, whereas the population of lactobacilli was unaffected. These observations indicate that short‐term use of chlorhexidine is of value in controlling oral infection of bumans by S. mutans.
Radiographic and clinical examination of periodontal status of first molars in 15–16‐year‐old Danish schoolchildren
Authors: HOOVER JEYARAJ NESAKUMAR , ELLEGAARD BIRGIT , ATTSTRÖM ROLF
Published: October 2007

Abstract – The prevalence of alveolar bone loss was investigated in 2813, 15‐ and 16‐year‐old Danish schoolchildren using bitewing radiographs. The interproximal spaces of the mesial and distal aspects of the first molar tech were examined. Inly defects with depths of more than 2 mm were considered periodontal bone loss. Radiographic evidence of bone resorption was found in 48 children. When evaluated clinically, 42 out of the 48 children with radiographic sings of bone loss demonstrated clinical loss of attachment. Only four children (0.1%) had the characteristic radiographic features of juvenile periodontitis. Loss of attachment of more than 2 mm was oberved in these children.
Systemic effects of oral use of chlorhexidine gel in multihandicapped epileptic children
Authors: RUSSELL BJÖRN G. , BAY LENA M.
Published: October 2007

Abstract— The purpose of this double‐blind study was to evaluate the effect on medical parameters after the daily use of chlorhexidine gel on multihandicapped epileptic children over a 2‐month period. Although certain abnormalities in hematologic and biochemical blood tests were recorded both prior to and after treatment, the prevalence of abnormalities was similar in the chlorhexidine and control groups, even though the patients in the study constituted a high risk group.
Ultrasonic dispersion of pure cultures of plaque bacteria and plaque
Authors: OLSEN INGAR , SOCRANSKY SIGMUND S.
Published: October 2007

Abstract – This study compared th somic sensitivity of 12 Gram‐negative and two Gram‐positive bacteria commonly encountered in plaque associated with periontal diseases. Pure bacterial cultures were groun to standard turbidity, diluted in 1/4 strength jprereduced anaerobically sterilized Ringer's solution, and aliquots dispersed for 0–180s, using and MSE sonic oscillator at 6 μm under 80% N2 10% H2 and 10% CO2. CO2. Viable recoveries were determined on anaerobically cultured trypticase soy 5% blood agar plates. Breakage of T. denticola was assessed by electron microscopy. Gram‐positive organisms tolerated sonication better than Gram‐negative. A. viscosus was more resitant than Strep. sanguis. Gram‐negative bacteria could be divided into groups according to their sensitivity. Eikenella corrodens was most resistant, followed by F. nucleatum. B. asaccharolyticus, Capnocytophaga gingivalis, A. actinomycetemcomitans, a strain (2097) of Group IV Racteroides, and B. melaninogenicus ss. intermedius ressted sonication better than “corroding” Bacteroides and oral Campylobacter. T. denticola, Selenomonas sputigena and Wolinella were most sensitive with viable counts which declined after sonication for 5–10s. Recoveries from plaque taken from five patients with periodontal diseases increased with sonication time, reaching higher values for supragingival than for subgingival samples.
Bacteriologic evaluation of the efficacy of mechanical root canal instrumentation in endodontic therapy
Authors: BYSTRÖM ANDERS , SUNDQVIST GÖRAN
Published: October 2007

Abstract – The presence of bacteria in 15 single‐rooted teeth, with periapical lesions, was studied throughout a whole period of treatment. The root canals were irrigated with physiologic saline solution during instrumentation. No antibacterial solutions or dressigs were used. Bacteria were found in all irnitial specimens form the teeth (median numver of bacterial cell 4x105; range 102‐107) and the number of strains in the specimens ranged from 1 to 10.88% of the strains were anaerobic. The most commonly isolated species were: Peptostreptococcus micros, Peptostrcptococcus anacrobius, Fusobacterium nucleatum, Bacteroides oralis, Bacteroides melaninogenicus subsp. intermedius and Eubacterium alactolyticum. Mechanical instrumentation reduced the number of bacteria considerably. Specimens taken at the beginning of each appointment usually contained 104‐106 bacterial cells and at the end 102‐103fewer. Bacteria were eliminated from the root canals of eight teeth during the treatment. In seven root canals bacteria presisted despite treatment on five successive occasions. There was no evidence that specific microorganisms were implicated in these persistent infections. Teeth where the infection persisted despite being treated five times were those with a hig number of bacteria in the initial sample.
Effect of the antibacterial agents octenidine and chlorhexidine on the plaque flora in primates
Authors: EMILSON C. G. , BOWEN W. H. , ROBRISH S. A. , KEMP C. W.
Published: October 2007

Abstract— The effect of the antibacterial substance octenidine on plaque formation and on oral microflora in eight monkeys fed a sucrose diet was studied. Plaque was obtained from buccal tooth surfaces of premolars and first molars in two quadrants using a swab and a dental carver and examined using culture and fluorescent antibody procedures. A significant reduction in plaque score was observed on the buccal tooth surfaces after daily topical application of 1% solutions of octenidine and chlorhexidine for 7 d; octenidine was more effective man chlorhexidine. Placebo treatment with water was without significant effect. Octenidine and chlorhexidine affected the plaque flora in a similar manner; the proportion of S. sanguis increased in relation to baseline levels while the population of Actinomyces, especially the group A. viscosus and A. naeslundii, was markedly reduced. S. sanguis showed an inverse relationship to members of Actinomyces in response to the action of the antimicrobial agents. Both plaque sampling methods revealed similar changes in bacterial composition as a result of treatment. The data show that octenidine is an effective inhibitor of dental plaque and its antimicrobial and antiplaque properties make it worthy of further studies.
Comparative effects of xylitol‐ and sucrose‐sweetened chew tablets and chewing gums on plaque quantity
Authors: REKOLA MAARIT
Published: October 2007

Abstract – The effects of chewing gums and chew tablets sweetened with sucrose or xylitoi on the quantity and adhesivity of dental plaque were studied with 14 volunteer dental students (mean age 23.2). The subjects participated in a four‐phase study in wliicfa one of four different test products was used! during each period. Tke 3‐d periods were interspaced with 4‐d normalization phases. The following four experimental products were tested : chewinggums (CG) and chew tablets (GT), sweetened withsucrose (&) orxylitol (×). The amount of plaque was determined through an automatic planimetric procedure on teeth treated with Dentotest°. The total plaque areas before brushing were significantly larger in the CTs group compared with the CTx group. After brushing, the plaque areas remained larger in the CTs group. In the determination of the thick plaque areas, the use of CTx was associated with significantly smaller plaque scores than the use of GTs. In the adhesivity studies CGx consistently yielded the lowest plaque scores, but the differences between x and s were not significant. The comparison between CT and CG suggested that CTx produced significantly smaller plaque scores than CGx before brushing, but not after. This finding was considered to result from the differences involved in the texture and chemical composition between tablets and chewing gums. The present study showed that the use of CGx and CTx was associated with clinically more advantageous plaque effects than the use of corresponding products sweetened with sucrose.
Zn concentration of human subgingival calculus related to F, Mg and Cu contents
Authors: KNUUTTILA MATTI , LAPPALAINEN ROLF , LAMMI SEPPO
Published: October 2007

Abstract – F and Zn content of human subgingival calculus was studied with respect to its Ca, Mg, Cu, Fe and Pb contents. The material consisted of 60 subgingival calculus samples from 60 persons. The element concentrations were determined with an atomic absorption spectrophotometer except for the F content, which was measured with an ion‐selective electrode. The data were analyzed using the multiple linear regression analysis. 24% of F content was explained by Zn and none of the other elements were significantly related to F content. Altogether 55.4% of Zn content was accounted for‐in all variables. The selected variables after the removal of nonsignificant ones explained 54.8%. The most important variable was F (24.0%) and the explanation power of Cu was 18.3% and of Mg 12.5%. The regression coefficients of these variables were positive. The mean ±s.d. concentration of Fin the samples was 221.2±174.1 μ/g and of Zn 498.6±499.1 μ/g, respectively.
ATP‐ase positive cells in human oral mucosa transplanted to nude mice
Authors: DABELSTEEN ERIK , KIRKEBY SVEND
Published: October 2007

Abstract – A model to study the differentiation of human oral epithelium in vivo utilizing transplantation of human tissue to nude mice has been described. Previous studies have described the epithelia cells in this kmodel. In this study we demonstrate that 8 d after transplantation, Langerhans cells, identified as ATP‐ase positive dendritic cells, have almost disappeared from the transplanted epithelium whereas at day 21 after transplantation such cells were abundant. It is suggested that the ATP‐ase positive cells which reappear in the transplanted epithelium are of mouse origin.
Effect ofintensive treatmetn with chlorhexidine on number of Streptococcus mutans in saliva
Authors: MALTZ M. , ZICKERT I. , KRASSE B.
Published: October 2007

Abstract – The effect of intensive treatment with chlorhexidine on the number of S. Mutans in saliva was studied in 24 schoolchildren highly infected with this organism. Chlorhexidine gel in individula dental trays was applied under supervision on two concecutive days, four times the first day an dthree times the second day. The number of S.mutans in saliva was monitored for 6 months. Immediately after treatment, the number was rreatlyreduced in all of the children. Thirty days after treatment only three children had more than 2×105 S.mutansmi saliva, and after 4 months, 11 children still had less than 2×105 S.Mutans/ml saliva. After 6 months the effect of the treatmetn was obvisous in 20% of the children. The results indicate that intensive treatment with chlorhexidine can be used to reduce the S.mutans infection. The antimicrobial treatment, however, should be individully controlled because of variations in the response of the subjects.
Enzyme histochemical studies of acid phosphatase isoenzymes in induced heterotopic bone formation in guinea pigs
Authors: NILSEN R. , MAGNUSSON B. C.
Published: October 2007

Abstract – A bone induction model was unsed to study the effect of different pretreatments and inhibitors added to the substrate media used for the histochemical demonstration of acid phosphatase activity. Two different acid phosphatases (AcP) were demonstrated. Tje AcP of matrix‐phosphatate activity. Two differet acid phosphatases (AcP) Were demonstrated. The AcP of matrix‐producing cells exhibited resistance to pretreatment with EDTA while it was sensitive to tartrate added to the incubation medium. The AcP in dentin resorbing cells was EDTA sensitive but resistant to tartrate. The AcP activities in both resorbing and matrix‐producing cells were generally sensitive to fluoride, copper and molybdate. In some of the dentinoclasts, Fluoride resistant AcP wsa observed. The results support previous investigations on normal bone formation, suggesting that at least two different isoenzymes of AcP exist. Once of these seemed to be related to matrix production and mineralization of the new heteotopic bone.
Laboratory study of fluoride impregnated toothpicks
Authors: MÖRCH TORMOD , BJORVATN KJELL
Published: October 2007

Abstract – The uptake of NaF in wooden toothpicks as well as the release of F from toothpicks impregnated with either sodium fluoride or amine fluoride was studied. The initial rate of fluoride uptake was found to be high, and an amount of NaF suitable for clinical use was obtained after immersing toothpicks in a 4% NaF solution for about 5 min. When immersed water or saliva, fluoride was rapidly released from the impregnated toothpick. The F− Concentration registered is saliva collected during use of fluoride impregnated toothpicks varied from about 0.1 part/106 F (amine fluoride impregnated toothpicks) to more than 50 parts/106 F (extended impregnation with NaF). The results indicate that teh clinical potential of fluoride impregnated toothpicks should be explored.
Presence of enamel on the lingual surface of rabbit permanent incisors
Authors: GREVSTAD HANS JACOB , SELVIG KNUT A.
Published: October 2007

Abstract – Permanent incisors from fetal New Zealand white rabbits aged 25–30 d in utero were processed for light microscopy. Examination of transverse and longitudinal sections of demineralized specimens revealed the development of a complete enamel covering of the incisal tip and an enamel extension on the linguoincisal surface of unerupted teeth, as evidenced by the presence and distribution of ameloblasts, enamel matrix and an enamel space. Formation of lingual enamel appeared to be completed within a few days before eruption of the incisor. The transition from the enamel‐covered to enamel‐free areas coincided with a gradual disintegration of the orderly ameloblast layer. The findings indicate that, histologically, the linguoincisal part of the rabbit permanent incisor is characterized by amelogenesis.
Effect of chlorhexidine mouthrinses on concentration of IgA in expectorates
Authors: ÖYDNA JOHN , GJERMO PER
Published: October 2007

Abstract – Secretary IgA is usually found in high concentrations in the mucin layer of the oral mucosa. Chlorhexidine (CH) has been shown to precipitate mucin and may thus, reduce the amount of IgA available in the oral cavity. Two human experiments were performed using single radial immunodiffusion (SRID) for quantitation of IgA in expectorates after mouth rinses. CH rnouthrinses eluted significantly more IgA from the oral cavity than did water. However, regular CH rinses for I week did not seem to reduce significantly the amount of IgA that could be extracted by water or CH. The present study did not support the suggestion that CH mouthrirases may reduce the IgA dependent defence mechanisms in the oral cavity.
Corrosion products of dental amalgam
Authors: JENSEN STIG JORGO
Published: October 2007

Abstract – Corrosion products from five amalgams with different Cu‐ and Zn‐contents were investigated by X‐ray diffraction technique. Powdered amalgam samples were treated with 1 % NaCl‐solution for up to 1 month. SnO2, ZnSn(OH)6 and CuSn(OH)6 were detected.
A modified phosphate‐bonded casting investment
Authors: FINGER WERNER , KOTA KOHICHI
Published: October 2007

Abstract – An experimental phosphate‐bonded casting investment with negligible setting‘expansion and a thermal expansion of 1.6%, sufficient to compensate for the solid thermal shrinkage of conventional dental gold alloys and high‐precious alloys for die porcelain fused to metal technique, is described. When used in a ringless casting technique the investment makes it possible to produce cast restorations with a consistent slidefit. In combination with a die spacer technique the new investment makes it possible routinely to produce cast restorations with a consistent and known, degree of loosefu.
Multiple forms of acid phosphatase in rat secretory enamel organ
Authors: MÖRNSTAD HÅKAN
Published: October 2007

Abstract – Acid phosphatase activity was studied biochemically in homogenates of secretory enamel organs from the rat. Incubations with crude homogenate failed to show distinct pH optima or kinetics characteristic for single enzymes. Crude homogenate activity was strongly inhibited by concentrations higher than 1 mM of NaF and Na‐tartrate, and higher than 10 mM of ZnSO4 and p‐bromotetramisole oxalate. lOmM MgCl2 gave a slight stimulation. CaCl2, KCl and EDTA were uneffective. Electrophoretic separation of the crude homogenate acid phosphatase on Triton X‐100 containing polyacrylamide gel demonstrated the presence of atleast three multiple forms of the enzyme. Two of them showed distinct pH optima at pH 4.4. The third one showed a broad pH plateau in the acid pH range. Kinetic studies of the three forms indicated single enzyme reactions. Two forms had electrophoretic mobilities similar to alkaline phosphatase. One form could be solubilized only after Triton X‐100 treatment. All forms were strongly sensitive to 10 mM NaF when added to the reaction mixture. The sensibility to 10 mM ZnSO4, CuSO4, Na‐tartrate and p‐bromotetramisole oxalate differed between the different forms.
Heat treatment of glass ionomer, silicate, zinc phosphate and zinc polycarboxylate cements
Authors: BRUNE DAG
Published: October 2007

Abstract – The compressive strength and erosion resistance of glass ionomer, silicate, zinc phosphate or zinc polycarboxylate cements, submitted to heat treatments at 50° or 70°C after mixing, have been assessed. Zinc phosphate cement specimens showed a marked reduction in compressive strength properties and erosion resistance, while minor improvements in compressive strength were observed for various brands of the other types of cements. For silicate cement a considerable improvement in erosion resistance was noted. One brand showed a reduction in the release of phosphate amounting to approximately a factor of 20. The various improvements observed may be clinically exploited by exposing the restoration after insertion to radiation from an external heat source which deposits radiation energy in the surface or bulk of the restoration.
Effect on plaque formation and acidogenicity of stored aqueous solutions of stannous fluoride
Authors: ELLINGSEN JAN EIRIK , RÖLLA GUNNAR , SVATUN BJARNE
Published: October 2007

Abstract – Stored aqueous solutions of SnF2 showed a reduced effect on plaque acidogenicity after 24 weeks, this being paralleled by reduced concentrations of Sn2+ and lowered pH. The plaque inhibiting effect was, however, maintained unchanged, indicating a different mechanism for this activity. Stored solutions caused a yellow dental stain probably consisting of SnS2.
Restorative resins: hardness and strength vs. quantity of remaining double bonds
Authors: ASMUSSEN ERIK
Published: October 2007

Abstract – It has been hypothesized that the Wallace indentation hardness of smooth surface resins is a factor of prime importance for the abrasion by food of Glass 1 restorations. In the present work factors affecting the hardness of polymers were investigated. In addition the tensile strength of composite resins was measured and related to the catalytic system of the polymer. It was found that for a given composition of the monomer the Wallace hardness number increased with increasing content of inhibitor, decreased with increasing content of peroxide, and was unaffected by changes in the content of amine. The hardness was well correlated with the quantity of double bonds remaining in the polymer. BISGMA‐based polymers showed no variation in hardness when the originating monomer varied with respect to content of a bi‐ or a trifunctional diluting monomer. Light‐polymerized polymers were relatively hard as compared to chemically cured materials of adequate setting time. The tensile strength of composite resins was predominandy determined by the monomer content of peroxide and increased herewith. The tensile strength was well correlated with the quantity of remaining double bonds in the constituting polymer.
Factors affecting the quantity of remaining double bonds in restorative resin polymers
Authors: ASMUSSEN ERIK
Published: October 2007

Abstract – The quantity of remaining unreacted double bonds may be a significant factor pertaining to the mechanical, physical and chemical properties of restorative resins. The said quantity was determined from the transmission IR‐spectrum of the materials before and after polymerization. For proprietary resins the quantity of remaining double bonds was found to vary between 23 and 43%. For experimental, chemically cured resins die quantity in question was found to decrease with increasing resin content of amine and peroxide, and to increase with the content ofinhibitor. The content of peroxide was the more influential of the three factors. For constant content of amine, peroxide, and inhibitor the number of remaining double bonds decreased with increasing content of diluting monomer in BISGMA‐based monomer mixtures. The use of a trifunctional monomer as diluting monomer did not give rise to a higher degree of conversion of the double bonds in comparison to a bifunctional diluting monomer. The quantity of remaining double bonds of a light curing material was relatively smaM when compared to the quantity present in chemically cured materials of adequate setting time.
Histochemical and biochemical study of here‐ditary fibrous hyperplasia of the gingiva
Authors: COLLAN YRJÖ , RANTA HELENA , VARTIO TAPIO , PERHEENTUPA JAAKKO , RAESTE ANNA‐MAIJA
Published: October 2007

Abstract – Four patients with herediatry hyperplasia of the gingiva were studies. Bipsy samples of gingival tissue contained subepithelial loose connective tissue with thick rounded fibroblasts or dense collagen‐rich connective tissue with thin fibroblasts, which appeared to be inactive These two types of fibroblasts differed in electron microscopy. alcian blue‐staining of intercellular material in various. MgCL2 concentrations was similar in hyperplastic and control samples. Collagen from the hyperplatic gngiva appeared to be more mature than normal, based onthe presence of stable, nonreducible cross lines. an investigation of growth harmone secretion and treatment trial suggested that the growth retardation observed in earlier studies was due to normal variation in growth rates (in one patient) to hypopituitarism associated with birth in breeth presentation.
Effect of caries preventive measures on Streptococcus mutans and lactobacilli in selected mothers
Authors: KÖHLER BIRGITTA , ANDRÉEN INGRID , JONSSON BERIT , HULTQVIST ELNA
Published: October 2007

Abstract – Mothers of first‐born babies were selected on the basis of high salivary counts of Streptococcus mutans. All experimental subjects were given a basic caries preventive program in order to decrease the level of S. Mutans in saliva. the program included dietary counseling, which stressed the role of sucrose in the accumulation of S. Mutans. The treatment was carried out in a public dental office. The effect of the treatment was assessed by microbiological examination of salivary levels of S. mutars and lactobacilli. a stratistically significant reducation in both S. mutans and lactobacilli was found. The basic preventive program was effective in reducing the nuber of S. mutans below a selected threshold value of 3000000 CFU per mlsaliva in 60% of the mothers. In the remaining subjects chlorhexidine treatment was required to suppress the salivary levels of S. mutans below this value.
Comparison between plaque inhibiting effect of chlorhexidine and aqueous solutions of copper‐and silverions
Authors: WALER SONNI METTE , RÖLLA GUNNAR
Published: October 2007

Abstract – Rinsing experiments with chlorhexidine, copper and silver solutions were performed in a group of volunteers. The plaque score ws measured after rinsing with the test solutions for 4 d and no mechanical oral hygiene allowed. Chlorhexidine and copper, both 1.1 mM solutions, gave reduced plaque scores, chlorhexidine being slightly more effective than copper, but the difference was difference was not statistically significant. A 1.1 mM solution of silver mitrate also showed a plaque inhibiting effect, statistically significant from the placcbo, but the effect was also significantly less than when chlorhexidine or copper were used. Copper ions may be of dimical interest because this is an essential metal in human nutrition with low loxicity