bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulpal response to a new visible light‐cured composite restorative material: Fotofil®
Authors: Bloch W. W. , Austin J. C. , Cleaton‐Jones P. E. , Wilton‐Cox H. , Fatti L. P.
Published: April 2006

Abstract A new visible light‐cured composite resin, Fotofil®, has been developed for the esthetic restoration of anterior teeth. The pulpal responses elicited by this material in unlined cavities and cavities lined with Dycal® were compared with those elicited by a negative control consisting of modified zinc oxide‐eugenol cement Nobetec® and a silicate cement Syntrex®. The pulpal responses were evaluated in the permanent maxillary and mandibular incisors in vervet monkeys using labial Class V cavities prepared in a total of 240 teeth. Two teeth were filled with each material in each monkey. Groups of 10 monkeys were killed at intervals of 2 days, and 2 and 8 weeks after restoration of the teeth.

The most severe pulpal responses were elicited by the unlined Fotofil® and Syntrex® restorations at all three time intervals. The Dycal® lined Fotofil® restorations elicited a milder pulp response than the Nobetec ® at 2 days and 2 weeks. No pulpal response was elicited by the latter two materials at 8 weeks.

These results clearly showed that Fotofil® and Syntrex® are irritant to the dental pulp up to 8 weeks. The placement of a Dycal® liner beneath Fotofil® restorations reduced the pulpal irritation elicited by this material to levels which were lower than those elicited by the Nobetec® control at 2 days and 2 weeks.
Microprobe and microradiographic studies of hyalin bodies in odontogenic cysts
Authors: Allison R. T.
Published: April 2006

Microprobe analysis of Araldite embedded sections of hyalin bodies revealed the presence of sulphur, chlorine, calcium and in some cases iron. The results have been compared with those obtained from control tissue sections of human heel skin, a thrombus occluded vessel and mineralized spherules in a dental follicle. Microradiographic studies showed that the density of hyalin bodies increased progressively towards the core. Isodensitracing confirms the laminar configuration of hyalin bodies as seen electron microscopically. The findings conform with the hypothesis that hyalin bodies originate as an epithelial secretion.
A study of the mineral phase of cementifying fibroma
Authors: Aoba Takaaki , Yoshioka Chihiro , Ogawa Yuzo , Yagi Toshio
Published: April 2006

Abstract Physico‐chemical study of a case of cementifying fibroma in the mandible of 78‐year‐old woman was carried out by X‐ray diffraction analysis and thermogravimetric and differential‐thermal analyses (TGA‐DTA). The center of the tumor consisted of masses of acellular cementum‐like tissues, while the periphery consisted of cementicle‐like tissues. X‐ray powder diffraction patterns showed that the mineral phase of these tissues was apatitic in nature. X‐ray line broadening analysis revealed that the crystallinity of apatite of the cementum‐like tissue was higher than that of apatite of cementicle‐like tissue, and lower than that of bone apatite obtained from the same patient. Furthermore, TGA‐DTA studies showed that the mineral (ash) value of cementum‐like tissue was slightly higher than that of bone.
A fine structural comparison of the healing of incisional wounds of mucosa and skin
Authors: Sciubba James J. , Waterhouse John P. , Meyer Julia
Published: April 2006

Abstract Incisional wounds of the same length and depth were made on tongue and dorsal skin of rats and the fine structural aspects of the responses of these were compared. Comparisons were made between the timing and degree of phagocytosis, the timing and rate of epithelial cell migration, of overall rate of healing, and of reformation of basal lamina and attachment complex in these two tissues. Phagocytic activity in epithelium and connective tissue of mucosa reached higher levels than in skin and the peak of activity in the epithelium of the mucosa was earlier than in the epidermis. Mononuclear phagocytes were active in phagocytosis, neutrophils showed little phagocytic activity‐Epithelial migration was found to begin earlier in mucosa than in skin. Epithelialization of the wound and repair of supporting tissue were completed earlier. The same sequence in the renewal of ultrastructural components of the hemidesmosome‐attachment complex was found in skin and mucosa, but was completed earlier at the mucosal site.

Mechanical and physical as well as physiologic factors may play a role in determining the differing rates of repair in mucosa and skin.
Odontogenic keratocysts: a clinical and histological study with special reference to enzyme histochemistry
Authors: Magnusson B. C.
Published: April 2006

Abstract. Of a total of 1,420 odontogenic cysts, 52 (3.3%) were diagnosed as odontogenic keratocysts. Clinical and histological findings in these 52 cysts are reported. Frozen sections of 26 of the keratocysts were incubated to show the following enzyme activities: NADH2‐ and NADPH2‐diaphorase, glucose‐6‐phosphate dehydrogenase, glutamate dehydrogenase, acid phosphatase, leucine aminopeptidase and ATPase. Furthermore, keratinization was studied with the rhodamine B method and lipids with the oil red O, the OTAN and the acid hematein methods. Sections from epidermis, oral mucosa, radicular cysts, residual cysts and follicular cysts served as reference material. The oxidative enzymes showed strong activity in the keratocyst epithelium which contrasted with weak activity in the reference cysts. Acid phosphatase activity was weak in all epithelia except that in keratocysts, which displayed a marked activity. In the fibrous capsule of the keratocyst a high activity of leucine aminopeptidase was recorded. This high activity contrasted with a weak activity in the reference material. The significance of the histochemical results in relation to the aggressive behavior of the keratocyst is discussed.
Lingual carcinogenesis in an inbred strain of hamsters
Authors: Marefat M. P. , Shklar G.
Published: April 2006

Abstract. Epidermoid carcinoma of the lateral border of the tongue can be induced in a standard strain of hamsters, applying DMBA in acetone after traumatizing the area with a root canal broach. Employing the same technique in an inbred strain of hamsters resulted in the more rapid development of carcinomas. The inbred strain should be a useful model for experimental carcinogenesis of tongue.
Histopathologic and bacterial evaluation of conventional and new copper amalgams
Authors: Heys Donald R. , Cox Charles F. , Heys Ronald J. , Loesche Walter J. , Avery J. K.
Published: April 2006

Abstract In vivo pulpal responses in monkeys and in vitro bacterial inhibition studies were completed on new copper amalgams, Sybraloy, ® Dispersalloy, ® Tytin® and a conventional Spheraloy® amalgam. Amalgams were placed in cavities lined with ZOE and in unlined cavities. Silicate and ZOE were used as controls. A total of 165 adult monkey teeth were evaluated at 3 days, 5 and 8 weeks. At 3 days the pulpal responses elicited by the copper amalgams appeared similar to conventional Spheraloy, ® all showing a slight to moderate response. At 5 weeks the majority of amalgams exhibited a slight pulpal response with a tubular reparative dentin under each restoration. The 8 week pulpal response showed a reduction of the inflammatory response characterized by a tubular reparative dentin with a uniform zone of predentin. Lined ZOE controls exhibited a slight response while silicate showed a moderate response with some persistent chronic inflammation. In vitro bacterial tests revealed that the various amalgams had little to no inhibitory effect on the three serotypes of S. mutans that are most prominent in humans.
Electron microscopic investigation of hyaline bodies in odontogenic cysts
Authors: El‐Labban Nawal G.
Published: April 2006

Abstract With the light microscope, hyaline bodies of Rushton may appear lamellar or granular. In s investigation, the ultrastructures of both lamellar and granular forms were studied in formalin fixed material, and in specimens fixed in osmium tetroxide. The lamellar type was composed of alternating electron dense and electron lucent layers, the outermost layer always being electron dense. The granular type was composed of amorphous material in which fragments of red blood cells could be Seen. Some hyaline bodies were partly granular and partly lamellar. The surfaces of the epithelial s apposed to both types showed large numbers of hemidesmosomes, but no basal lamina was seen, ne amorphous material in the granular hyaline bodies appeared very similar to the substance of the generating red blood cells, and extravasated red cells were commonly found in the adjacent connective tissue. The results suggest that the granular type is formed from degenerating red blood cells, and that the lamellar pattern may result from segregation of components within the mass rather an by an incremental form of growth. No support was found for the hypotheses that hyaline bodies e keratinous or a secretory product of the epithelial cells.
Light and ultrastructural relationship between oxytalan fibers in the periodontal ligament of the guinea pig
Authors: Edmunds R. S. , Simmons T. A. , Cox C. F. , Avery J. K.
Published: April 2006

Abstract The interfaces and the relationships between collagen and oxytalan fibers were observed d light and electron microscopy. Guinea pig periodontal ligament was prepared for light and electron microscopy with perfusion using Peter's buffered formalin for light microscopy and GTA‐S‐collidine and OSO4 for electron microscopic studies. The tissue for light microscopy was stained with a modified Gomori's aldehyde fuchsin technique, in which pre‐oxidization with potassium monopersulfate was carried out before staining so as to demonstrate the oxytalan fibers. EM tissues were routinely stained with lead citrate and uranyl acetate.

Two different structural relationships were observed. First, the subcomponents of the collagen and oxytalan fiber types interweave with each other; and, second, some of these two‐fiber subcomponents appear attached to each other. These relationships and the known orientation of oxytalan fibers as seen in the periodontal ligament provide insight as to the function of oxytalan fibers. The oxytalan fibers may provide increased structural integrity and increased distribution of forces over a wider area of the periodontal ligament. Because of their close relationship to blood and lymph vessels in the periodontal ligament, they may also help to stabilize these elements by the same structural relationships to collagen fibers.
Immunologic manipulation of DMBA tumorigenesis in hamster cheek pouch by DNCB contact hypersensitivity
Authors: Mohammad Abdel Rahim
Published: April 2006

Abstract. Hamster cheek pouches were sensitized with the potent allergen DNCB either before the initiation of DMBA tumorigenesis or by direct application to already developed tumors. Among animals treated prior to tumorigenesis induction there was an apparent delay in onset of tumors and decreased rate of tumor growth. Direct application of DNCB to already established tumors seemed to temporarily arrest tumor growth; later, however, tumor growth rate resumed to approximately that in untreated control animals. It is concluded that DNCB contact hypersensitivity may exert some influence on the DMBA tumorigenesis process as manifested by delay in tumor onset or by temporarily retarding growth of established tumors. It appears that DNCB sensitization prior to tumorigenesis is generally more effective than DNCB applied after tumor development.
224Ra and 226Ra experimentally induced dental changes in rats
Authors: Reichart P. A. , Althoff J. , Eckhardt W. , Rippel W.
Published: April 2006

Abstract. Sprague‐Dawley rats received intragastrically a single dose of 226Ra or 224Ra once weekly for 21 weeks. During this period the animals of both groups were thus exposed to comparable doses. After 12 weeks, a shortening of the maxillary incisors was observed, and this progressed during the course of the 55–week experiment. Radiologically, a loss of pulpal transparency and an apical irregular opacity in the maxillary incisors were demonstrable. Histologically, dysplastic changes of the maxillary incisors and multiple resorptions at the cemento‐enamel junction of the molars were seen. The observed alterations were more pronounced in the 226Ra group than in the 224Ra treated group. The experimentally induced resorptions were comparable to those observed in patients who had incorporated 224Ra or 226Ra. Clinical, radiological, histological, γ‐spectrometrical, and autoradiographical findings, as well as dose‐estimations, are described.
Pigment in the lining of nasopalatine duct cysts: report of two cases
Authors: Stam F. C. , van der Waal I. , van der Kwast W. A. M.
Published: April 2006

Abstract. In a review of 20 nasopalatine duct cysts, two cases were encountered with a pigmented epithelial lining. In the literature we have found one similar case only. The pigment in our cases was shown to be melanin. The authors suggest that the melanin‐containing epithelial cells are derived from Jacobson's organs and, therefore, most likely should be considered olfactory epithelium.
The effect of DMBA on hamster cheek pouch mucosa in vitro
Authors: Mock D. , Main J. H. P.
Published: April 2006

Abstract Neonatal hamster cheek pouch mucosa was treated with DMBA for three h either before being explanted or after 7 days in vitro. The epithelium of the treated cultures exhibited dysplasic changes, most marked at 21 to 28 days in vitro. These changes were not seen in the explants maintained for 35 to 49 days in vitro indicating a return to an apparently normal morphology. Examination of the ultrastructure of DMBA treated and untreated explains showed changes consistent with those described in similar tissues in vivo. The epithelium of the carcinogen treated tissue exhibited widened intercellular spaces, tortuous cell membranes, an irregular and discontinuous basal lamina and pseudopodia of the basal cells extending into the underlying mesenchyme. Similar changes have been described in inflamed epithelium, in some other experimental preparations, and in premalignant lesions in vivo, both in animals and man.
Correlated microradiography, X‐ray microbeam diffraction and electron probe microanalysis of calcifications in an odontoma
Authors: Aoba Takaaki , Yoshioka Chihiro , Yagi Toshio
Published: April 2006

Abstract Using microradiography, X‐ray microbeam diffraction and electron probe microanalysis, a correlated morphologic and crystallographic study was performed on dysplastic enamel in a compound odontoma. The tumor was found in the lateral incisor‐canine region of the left mandible of a 36‐year‐old woman. A conspicuous feature was the presence of hypomineralized areas, which were situated in the proximity of enamel surface and distinctly demarcated from the adjacent enamel. X‐ray microbeam diffraction and electron probe microanalysis showed that these lesions have a lower crystallinity and a higher concentration of magnesium as compared with the adjacent enamel. In addition, the present study revealed the presence of two other types of calcifications: (1) calcified structures within the fissure or on the enamel surface, which include lacunae of varying size and which resemble a form of coronal cementum, and (2) spherical calcifications which may be an epithelial product.
Histochemical studies of obstructive adenitis in human submandibular salivary glands. II. Lectin binding and keratin distribution in the lesions
Authors: Nakai M. , Tsukitani K. , Tatemoto Y. , Hikosaka N. , Mori M.
Published: April 2006

Lectin‐binding profiles and keratin distribution in obstructive adenitis of human submandibular glands (SMGs) are reported and compared those of normal SMGs. Histologically, obstructive changes in the SMGs included acinar atrophy, duct‐like structure formation in the early stage, and disappearance of acinar cells and dilation of ductal segments in the later, chronic stage. The following lectins were used: Con A (Glc. Man), PNA(Gal, GalNAc). RCA1I(Gal), DBA(GalNAc). SBA(Gal, Gal‐NAc). UEA‐1(α‐L‐Fuc) and WGA((GlcNAC, NeuNAc). Lectin staining in atrophie acinar cells was usually reduced except for SUA binding and was irregularly distributed in altered acinar and ductal epithelia. Binding of DBA and UEA‐1 lectins were particularly intense along the luminar borders of ductal segments in the lesions. Immunohistochemically detectable keratins were characterized by intense staining in atrophie acinar cells and in all the ductal segments, whereas normal acinar cells, either serous or mucous, were negative.
Vital apicoectomy of the teeth: a 1–4 week histopathological study in Macaca mulatto
Authors: Ellis E. , Cox C. F. , Hitchcock R. , Baker J.
Published: April 2006

Several studies have reported devitalization of teeth following surgical procedures in the area of the root apices. The purpose of this investigation was to observe the 1–4‐week wound healing pattern in monkey dental tissues following intentional vital apicoectomy (IVA). Two adult Macaca mulatta were used in this study. All of the teeth were surgically transected within the apical one‐third with a bur. The soft tissues were then closed. At death, a maxillary and a mandibular quadrant for 1, 2, 1 and 4 weeks following surgery were obtained after vascular perfusion. Each quadrant was demineralized in HDTA, processed, serially sectioned at 7 μm and alternately stained with hematoxylin and eosin, Preece's modified trichome, and McKay's bacterial stains. Examination of sequential IVA cuts showed an initial disruption of the pulpal neurovascular supply resulting in pulpal necrosis. The pulpal tissue underwent a process of replacement with PDL‐like connective tissues and deposition of cementum on all cut dentin surfaces of the tooth roots as well as in some of the pulp chambers No abscesses, external resorption or ankylosis were found.
Lectin histochemistry of submandibular glands following duct‐ligation in mice and rats
Authors: Takai Y. , Asano K. , Clemente R. P. , Mori M.
Published: April 2006

Lectin binding patterns of Con A. PNA, SHA, DBA, WGA, RCA‐1 and UEA‐1 were tarried out in duct‐ligated submandibular glands (SMGs) of rats that diplayed acute degenerating changes Lectin staining was also related to histologic changes. Proliferating epithelial cells which were probably derived from intercalated duet cells showed a strong SBA and WGA staining on the 3rd day. Duct‐like and cystic structures appeared on the 7th day and staining by PNA, SBA. WGA. RCA‐1 and Con A was described In mice. lectin binding after duct ligation appeared similar to the rat In the long‐term observation of mice SMGs. acinar cell regeneration occurred between the 2lsl and 42nd days and they stained strongly for DBA.
The effect of chronic inflammation on gingival connective tissue proteoglycans and hyaluronic acid
Authors: Bartold P. M. , Page R. C.
Published: April 2006

Proteoglycans have been isolated and analysed from extracts of normal and chronically inflamed human gingiva in order to determine the effects of chronic inflammation on these important soft connective tissue extracellular macromolecules. The uronic acid content of glycosaminoglycans isolated by papain digestion of normal and inflamed gingiva did not differ significantly. Likewise, electrophoretic analysis revealed that the content of hyaluronic acid, heparan sulfate, dermatan sulfate and chondroitin sulfute was similar. The sulfated glycosaminoglycans from both sources eluted from a Sepharose C1‐6B column with a Kav of 0.45 (approximate Mr 25,000). However, hyaluronic acid from normal gingiva was predominantly of a large size eluting in the void volume of a Sepharose. CL‐6B column, while that isolated from inflamed tissue was mostly a small molecular weight species which elutccl in the included volume of a Sepharose CL‐6B column. Using dissociative conditions, intact proteoglycans could be more readily extracted from inflamed tissues (90% of the total tissue uronic acid) than from normal tissues where only 80% of the total tissue uronic acid was extractable. Even though DEAE‐Sephacel ion‐exchange chromatography revealed no differences in charge between normal and inflamed gingival proteoglycans, Sepharose CL‐4B chromatography revealed more molecular size polydispersity in samples from inflamed tissue than from normal tissue. Taken together, these results indicate that while hyaluronic acid is depolymerized in inflamed tissue, no evidence of sulfated glycosaminoglycan degradation was found. Therefore, the most likely cause for disruption to the molecular integrity of the proteoglycans is via proteolytic alteration to the proteoglycan core protein.
Challenges in clinical dental traumatology
Authors: Andreasen J. O.
Published: April 2006

Abstract Traumatic dental injuries are very frequent in both the primary and permanent dentition. As these often imply combined injury to both the pulp and periodontium, a variety of healing complications may arise, such as pulp necrosis, pulp canal obliteration, root resorption and loss of marginal attachment. Furthermore, trauma in the primary dentition can be transmitted to the permanent successors, leading to a variety of developmental disturbances. The analysis of the etiology of these complications has hitherto been seriously hampered by a lack of agreement on the registration of the extent of injury to the tooth and its supporting structures (i.e. trauma classification), lack of agreement on the definition of healing complications and shortcomings in the statistical analysis of follow‐up studies of traumatized primary and permanent teeth. The consequences of these shortcomings are described with respect to the evaluation of prognosis of various types of trauma. Suggestions are made for data collection and analysis of future trauma studies which should enable the identification of factors determining the outcome of traumatic dental injuries. Through a perusal of recent dental literature, various trauma entities and treatment procedures are evaluated. Furthermore, areas are outlined where present knowledge does not allow rational treatment selection or prognosis evaluation.
Clinical suitability of a sonic vibratory endodontic instrument
Authors: Barnett F. , Godick B. , Tronstad L.
Published: April 2006

Abstract A sonic vibratory device with the shape, size and weight of a dental handpiece has been developed for the instrumentation of root canals. Specially designed K‐type files are used with the handpiece, which is air‐driven and may be attached to the high‐speed air line of a dental unit. A clinical study was performed using conventional hand instruments and the sonic system in the instrumentation of root canals. Also studied was the use of continuous irrigation of the root canal with EDTA and filtered tap water with the sonic device. Instrumentation time, procedural and clinical complications, as well as overall suitability of the new device were evaluated. The results indicated that the sonic vibratory system was well‐suited for root canal instrumentation. The vibratory files appeared safe and complications were well within acceptable limits. Irrigation with a continuous flow of EDTA was not acceptable, mainly because of crystallization and clogging of tubes and handpieces. Filtered tap water was well‐tolerated and its cleaning effect was good. The sonic device could be used with ease and resulted in decreased operator fatigue when compared with hand instrumentation.
Hyaline bodies and giant cells associated with a radicular cyst
Authors: Yang Z‐P. , Barnett F.
Published: April 2006

Abstract This case report describes an unusual granulomatous lesion that was curetted from the apices of 2 endodontically treated teeth. Microscopic evaluation revealed a radicular cyst with irregularly shaped eosinophilic hyaline bodies in close association with giant cells. Sections were stained with periodic acid‐Schiff with and without diastase to evaluate the nature of the hyaline bodies. These stains revealed the presence of a carbohydrate material, possibly of plant origin. However, since starch cells could not be demonstrated morphologically, a definitive diagnosis of pulse granuloma was not made.
Early tissue reaction to endodontic filling materials
Authors: Olsson Berit , Wennberg Alf
Published: April 2006

Abstract The tissue compatibility of gutta‐percha or gutta‐percha coated with 6 different root canal sealers was evaluated. A modified implantation technique, permitting short‐term observations, was used. A total of 207 implants were placed in the muscle tissue of rabbits, and the tissue reactions were observed microscopically at. 1, 7, or 14 days after implantation. Gutta‐percha caused a slight tissue reaction at all observation periods. Three different reaction patterns were observed among the sealer implants. Grossman's sealer caused a rather slight initial tissue reaction which increased to a moderate level. Kloroperka N‐Ø and zinc oxide‐eugenol cement maintained a moderate/severe reaction throughout the 14‐d observation period. Diaket and AH26 caused a severe initial reaction which persisted at 7 d and had decreased slightly at 14 d. A similar reaction pattern was seen in the rosin chloroform series, but here the initial tissue reaction receded substantially, and only a slight reaction was observed at 14 d.
Biologic root‐end closure on a traumatized and surgically resected maxillary central incisor: An alternative method of treatment
Authors: West Nathaniel M. , Lieb Richard J.
Published: April 2006

Abstract A 23‐year‐old female presented with a history of trauma to the maxillary right central incisor at age 7 which had been treated using conventional endodontic techniques. At 12 years of age the root of the incisor was resected and the periapical area curetted. The maxillary right central incisor was successfully treated using Frank's apexification technique and subsequently obturated with gutta percha using lateral condensation. The results suggest that biologic root‐end closure (apexification) can be achieved on teeth that have been previously subjected to periapical surgery.
Divergent types of repair associated with root fractures in maxillary incisors
Authors: Mata Estuardo , Gross Marvin A. , Koren Larry Z.
Published: April 2006

Abstract Calcium hydroxide was successfully used as a temporary intracanal filling material in the treatment of 2 teeth with horizontal root fractures. Radiographic examination indicated that two different types of repair had occurred. The first was healing with calcified tissue and the second was healing with hone and connective tissue. The patient was seen at a 1‐year post‐treatment follow‐up and there was substantial evidence of repair around both roots.
Radiographic and clinical estimation of endodontic treatment need
Authors: Petersson Kerstin , Wennberg Alf , Olsson Berit
Published: April 2006

Abstract The purpose of this investigation was to examine the relationship between the need for endodontic treatment found by radiographic examination, and the actual treatment received by patients in an undergraduate endodontic clinic. The material consisted of 610 teeth in 387 patients. The need for endodontic treatment was detected in radiographs in 39% of the teeth, during operative procedures in 39%, and during the planning for prosthetic treatment in 22% of the cases. The relationship among these three means of detection was found to vary with age and tooth type. However, in all groups, less than half the actual need for endodontic treatment was revealed by radiographic examination alone.
Effect of irrigation solutions on the filling of lateral root canals
Authors: Goldberg Fernando , Massone Joaquin Enrique , Spielberg Carlos
Published: April 2006

Abstract An in vitro study involving 66 single–rooted human teeth was performed. The teeth were divided into 3 groups: control group, root canals instrumented and irrigated with distilled water; experimental group A, root canals instrumented and irrigated with 15% EDTA; and experimental group B, root canals instrumented and irrigated with 5% sodium hypochlorite. All canals were filled with laterally condensed gutta‐percha and Diaket® A. Radiographs were taken mesiodistally and buccolingually and the number of lateral canals filled in the various teeth was counted. The group treated with 15% EDTA showed a significantly larger number of filled lateral canals than the groups irrigated with distilled water or sodium hypochlorite.
Book Review
Authors: Riso Kenneth
Published: April 2006

Books reviewed in this articles:

John Ide Ingle & Jerry F. Taintor: Endodontics.
Microbial microleakage and pulpal inflammation: A review
Authors: Browne Roger M. , Tobias Rosalind S.
Published: April 2006

Abstract The evidence relating microbial microleakage and pulpal inflammation is reviewed. In vitro experiments show that all current dental materials permit fluid microleakage at the material/cavity wall interface. in vivo, this fluid microleakage is accompanied by bacterial growth, unless the material has lasting antibacterial properties. An association does exist between the presence of bacteria at the material/cavity wall interface and the presence of pulpal inflammation. The role of the smear layer m minimizing the harmful effects of microbial microleakage and of chemical toxicity of restorative material is reviewed. Further research should be aimed at eliminating microleakage by the development of more fully adhesive materials or by improving their antibacterial properties.
Effect of calcium hydroxide treatment on periodontal repair and root resorption
Authors: Hammarström Lars , Blomlöf Leif , Feiglin Barry , Lindskog Sven
Published: April 2006

Abstract Pulpal application of calcium hydroxide is a common treatment for external root resorption. Several mechanisms of action have been suggested. In the present investigation, the effect of pulpal calcium hydroxide on cells at the root surface and in the periodontal ligament was studied by means of scanning‐electron microscopy and light microscopy. Lateral incisors in monkeys were extracted, a groove was made‐ in the root surface and the teeth were then immediately replanted. The pulps of some teeth were infected by bacteria from the saliva. Application of calcium hydroxide in the root canal caused a limited necrosis of the cells resorbing dentin as well as the cells forming reparative cementum in the experimental groove. In the non‐infected teeth, a temporary ankylosis developed. The high pH having a bactericidal and necrotizing effect seemed to be sufficient to explain the therapeutic effect of calcium hydroxide on root resorption.
Root and pulpal dentin after surface demineralization
Authors: Hanes P. J. , Polson A. M. , Frederick G. T.
Published: April 2006

Abstract Previous studies have indicated that there may be a difference in connective tissue response to surface demineralized dentin from root and pulpal surface regions. Consequently, it was the purpose of the present investigation to examine the initial surface characteristics of the dentin from these regions to determine if there were differences which could enhance interactions with adjacent connective tissues. Rectangular dentin specimens with opposite faces of root and pulpal region dentin were immersed in a saturated solution of citric acid, pH 1, for 3 min, rinsed, and prepared for examination in an ISI‐40 SEM. Comparisons were made between root and pulpal surfaces of the specimens, and with non‐acid treated controls. Control specimens were characterized by the presence of a smear layer which obscured the openings of dentinal tubules on all surfaces. Citric acid treatment removed the smear layer, resulted in exposure of dentinal tubule orifices, and produced a mat‐like, fibrillar surface texture. The pulpal surface had a more coarse appearance than the root surface. Quantitation of the number and diameter of tubule orifices showed larger values for the pulpal surface. The percentage of die surface area occupied by tubule orifices was significantly greater on the pulpal aspect. It was concluded that surface demineralization of dentin from the pulpal region results in exposure of a greater amount of collagen substrate, and the latter may predestine an enhanced interaction with connective tissue components.
Periodontal factor in forced eruption of fractured human incisor
Authors: Peretz Benjamin , Wein‐berg Thomas W. , Kohavi David
Published: April 2006

Abstract A case is presented with both vertical and horizontal root fractures. Roentgenographic diagnosis revealed only the horizontal component of the fracture. On completion of the forced eruption it was evident that the sound tooth structure was still subgingival. Periodontal probing showed a deep vertical component of the fracture which was not diagnosed on previous examination. This misdiagnosed case emphasizes the need for complete periodontal examination in a subgingivally fractured tooth.
Book Review
Authors: Greenberg Martin S.
Published: April 2006

Harold Gelb (ed).: Clinical Management of Head Neck, and TMJ Pain and Dysfunction, a Multidisciplinary Approach to Diagnosis and Treatent.
Bonding of enamel‐dentin crown fractures with GLUMA® and resin
Authors: Andreasen Frances M. , Rindum Judith L. , Munksgaard E. Christian , Andreasen Jens O.
Published: April 2006

Abstract A procedure is described whereby enamel‐dentin fragments can be bonded to the remaining tooth substance. The tooth and tooth fragment are conditioned with EDTA and GLUMA® and then bonded together with a light‐cured composite resin. Results based on the restoration of 76 complicated and uncomplicated crown fractures of permanent incisors with up to 2 years' observation indicate that teeth bonded with GLUMA® can withstand normal chewing forces. Long‐term studies on the retention of bonded fragments, color stability and pulpal reaction to bonding are now in progress.
Effect of a tight seal on survival of bacteria in saliva‐contaminated cavities filled with composite resin
Authors: Mejàre Ingegerd , Mejàre Bertil , Edwardsson Stig
Published: April 2006

Abstract Buccal Class V‐cavities were prepared on homologous pairs of human premolars in vivo under aseptic, conditions. The cavities were then contaminated by rubbing them with a cotton pellet soaked in saliva. Chosen by lot, 1 tooth in each pair was thereafter washed either with water spray or with an antimicrobial cleanser (Tubulicid®). The cavity was filled with Adaptic®. The cured filling was removed to about, half of the depth and replaced by a zinc, sulphate cement. Finally, an orthodontic band was cemented over the filling. The teeth were extracted after 6–8 weeks. Both culturing and histological techniques were used to assess possible growth of bacteria. The results showed no growth of bacteria under the composite resin restorations, independent of whether the cavity was washed with water or with an antimicrobial cleanser before filling. Thus bacteria originating from saliva contamination do not seem to survive under tightly sealed composite resin restorations.
Obturation of root canals by the standardized and step back techniques
Authors: Santini Ario
Published: April 2006

Abstract The objective of this study was to assess undergraduate students' ability to obturate the apical third of the root canal of human maxillary incisors using the standardized technique and the step back technique as taught in the undergraduate curriculum. Twenty‐six students prepared and obturated the canals of 104 extracted teeth to a given working length. The teeth were coated with nail varnish to prevent leakage and incubated for 2 wk at 37°C in Procion Brilliant Red before being evaluated for linear leakage. Adaptation of root fillings was assessed at 0.5 mm intervals from the apex in every case. There was significantly more leakage with poor adaptation when students used the step back technique compared to the standardized technique. Overfilling frequently occurred with the former method and never with the latter.
Diminutive lateral incisor as replacement for an avulsed permanent central incisor tooth
Authors: Stokes Alastair N. , McClea C. Peter J.
Published: April 2006

Abstract Orthodontic space closure together with crowning to regain dental arch symmetry is a preferred therapy for unilateral anterior tooth loss. A case is reported in which a diminutive upper lateral incisor was moved laterally, stabilized and crowned to resemble an upper central incisor in circumstances where most authors would recommend the provision of a removable prosthesis.
Tissue response to dental caries
Authors: Langeland Kaare
Published: April 2006

Abstract Caries still represents the most widespread human disease. The pulp tissue sequelae of den tin caries are of utmost importance, because prevention of pulpal damage considerably reduces the need for extensive restorations and endodontic therapy. There is, however, considerable disagreement in the literature regarding how early the pulpal response to caries can be detected. The material in this article, gathered from the author's and his coauthors' earlier investigations, deals with pulp reactions from initial caries to increasingly extensive caries; caries in combination with attrition; the effect of carious den tin in experimental cavities of intact dentin; the effect of medicaments, restorative procedures and materials, and indirect pulp capping in the treatment of deep caries; microbiologic aspects of dentin caries; diagnosis criteria for treatment; light and electron microscopic study of teeth with carious exposure; periodontal disease and root caries in the geriatric population; pulp biopsies of teeth with periapical lesions, and the breakdown of the remaining pulp and its periapical sequelae. Pulpal reactions to initial caries detected as early as bacteria reach the dentinal tubules arc also discussed. As in medium and deep caries, this can be reversible following the removal of the infected dentin, except for irritation dentin and calcifications on the canal walls or free in the lumen. Bacteria remaining in dentinal tubules combined with iatrogenesis may be the reason for pulpal disintegration under deep restorations. Indirect pulp capping is not an acceptable procedure. Pain (or lack thereof) is not a predictable indicator of the inflammatory stage of the pulp. Root caries must be treated early to prevent pulpal destruction. Vital pulp tissue can be found in the roots of teeth with periapical radiolucencies that will ultimately show the presence of bacteria.
Influence of delayed coronal permanent restoration on endodontic prognosis
Authors: Safavi Kamran E. , Dowden William E. , Langeland Kaare
Published: April 2006

Abstract The results of periodic follow‐up examinations of root‐filled teeth with temporary and permanent restorations were compared. Successful results were observed more frequently in teeth with permanent restorations than in teeth with temporary fillings. The difference, however, was not statistically significant. A firm correlation between the type of coronal restoration and endodontic prognosis could not be established within the observation period.
Endodontic‐access adhesive bridges
Authors: Chandler Nicholas Paul , Stockdale Charles Robert
Published: April 2006

Abstract Acid‐etch retained appliances have a role in the management of dental trauma, both as splints and for the replacement of missing teeth. Two clinical cases are described. In the first, a tooth with a fractured root is used as an abutment for a bridge that replaces an avulsed tooth. The metalwork is modified with a “window” to facilitate endodontic therapy should this become necessary in the future. In the second case, an etched splint with a “window” supports a tooth of poor prognosis while an endodontic implant is placed and healing occurs. Further designs are considered for applications in similar circumstances.
Severe root resorption of fractured maxillary lateral incisor following endodontic treatment and orthodontic extrusion
Authors: Årtun Jon , Aamdal Hilde M. Aa.
Published: April 2006

Abstract A case with extensive root resorption following endodontic treatment, orthodontic extrusion, and prosthetic restoration of a maxillary lateral incisor that had fractured in the cervical area due to trauma is documented. The treatment procedures are described in detail and possible reasons for the resorption are discussed. It may be classified as a cervical root resorption initiated by injury to the cervical attachment apparatus and the cervical root surface.
A one‐year follow‐up of partial pulpotomy and calcium hydroxide capping in primary molars
Authors: Schröder Ulla , Szpringer‐Nodzak Maria , Janicha Jadwiga , Wacińska Maria , Budny Jerzy , Mlosek Krzysztof
Published: April 2006

Abstract Partial pulpotomy and capping with calcium hydroxide was performed in 93 lower primary molars. The pulpal diagnosis was chronic coronal pulpitis. The amputation was done with a gentle technique, using high speed and diamond burs. Calcium hydroxide was applied to the wound surface without any intermediate layer of blood clot. The cavity was sealed with slow‐setting zinc oxide‐eugenol cement, phosphate cement and silver amalgam.

The teeth were followed clinically and roentgenologically. After one year 67 successful endodontic treatments and 14 failures were registered. The remaining 12 teeth were lost for reasons unconnected with the endodontic treatment. The frequency of successful treatments, estimated with the aid of a modified life table method, was 83%.

Partial pulpotomy thus proved favorable compared to traditional coronal pulpotomy and should therefore be considered the treatment of choice in primary molars with chronic coronal pulpitis provided a gentle surgical technique is used and no blood clot is left between wound surface and calcium hydroxide.
A technique to reinforce weakened roots with post canals
Authors: Lui J. L.
Published: April 2006

Abstract A method to strengthen the weakened coronal portion of roots with post canals is described. The apical portion of the root canal is prepared using a Dormer twist drill to fit a matching Wiptam wire post. After removal of the Wiptam wire, the root canal of the weakened coronal portion of the root is prepared and acid‐etched. The Wiptam wire, lubricated with petroleum jelly, is repositioned into the root canal, and after painting the coronal root den tin with bonding agent, radiopaque composite resin is syringed around the wire into the coronal defect. Following polymerization of the composite material, the wire is removed, leaving a reinforced root with a patent post canal. Preparation of the root face is completed for restoration with a post crown.
Pulpal response to topical application of citric acid to root dentin
Authors: Lambrianidis Theodor , Tziafas Dimitrios , Kolokuris Ioannis
Published: April 2006

Abstract The purpose of the present study was to investigate the pulpal reactions to citric acid (pH 1.0) applied for 3 min to exposed root dentin. We used 48 roots of 24 maxillary and mandibular third and fourth permanent premolars from dogs divided equally into experimental (citric acid) and control (saline) roots. Following surgical exposure of the buccal root surface and the removal of the cementum with a Gracey curette, citric acid or saline was applied on the exposed dentin. The pulpal reactions were histologically evaluated 1, 7 and 15 days postoperatively using hematoxylineosin stained sections. Results obtained from 43 specimens showed no difference in the pulpal response at any of the observation intervals between citric acid and saline‐treated teeth.
An enzyme histochemical study of the influence of formocresol and calcium hydroxide on the dental pulp
Authors: Eronat N. , van Mallem P. J. , Wijnbergen M.
Published: April 2006

Abstract Sections of goat incisor pulps were studied after a 5‐min application of formocresol (FC) or after calcium hydroxide or saline/ZnOE treatment followed by freeze‐sectioning. After 3–7 days the incisal part of the pulp was necrotic, as shown by absence of lactate dehydrogenase (LDH) activity. The necrotic zone was much larger after FC than after saline/ZnOE or calcium hydroxide. The LDH negative area after application of FC appeared to consist of a layer showing nuclei that were well‐preserved by the formaldehyde from the FC, and an area of tissue breakdown, which showed no or a reduced structure according to hematoxylin and eosin. Well‐preserved nuclei were not found in the 2 other groups. After 14 days all necrotic tissue, except that subjacent to calcium hydroxide, had been replaced by vital (LDH‐positive) tissue. After saline/ZnOE or calcium hydroxide treatment, hard‐tissue formation was found in all teeth, and after FC treatment in the majority of teeth.
Evidence for direct inhibition of dentinoclasts by a corticosteroid/antibiotic endodontic paste
Authors: Pierce Angela , Heithersay Geoffrey , Lindskog Sven
Published: April 2006

Abstract A previous report demonstrated that intrapulpal application of an antibiotic/corticosteroid combination effectively eliminates experimentally induced external inflammatory resorption in monkey teeth. The aim of this study was to examine the direct effects of this medicament on dentinoclasts cultured in vitro. Isolated dentinoclasts were cultured in the presence of either the endodontic paste or antibiotics. Results showed that the steroid component of the paste directly inhibited the spreading of dentinoclasts, suggesting that this medicament acts by detaching resorbing dentinoclasts from the root surface.
Painful dysesthesia of the inferior alveolar nerve following use of a paraformaldehyde‐containing root canal sealer
Authors: Kleier Donald J. , Averbach Robert E.
Published: April 2006

Abstract This case report offers further documentation that paraformaldehyde‐containing pastes are capable of causing long‐term anesthesia and dysesthesia of the inferior alveolar nerve when accidental overfilling of mandibular posterior teeth occurs during endodontic obturation. Nerve damage occurred even though the paste was used in conjunction with a solid core filling material (gutta‐percha). Possible mechanisms of nerve damage are discussed and treatment recommendations are made.
Long‐term splinting of maxillary incisor with intra‐alveolar root fracture
Authors: Rabie Geoffrey , Barnett Frederic , Tronstad Leif
Published: April 2006

Abstract This case report describes the treatment of a maxillary right central incisor with an intra‐alveolar horizontal root fracture in the coronal one‐third of the root. Repositioning and immobilization of the coronal fragment were carried out. After 2 months the clinical examination revealed the pulp in the coronal fragment to be necrotic. Radiographically, a small periapical radiolucency was seen. Endodontic therapy was initiated and the pulp in the apical fragment proved to be necrotic as well. Instrumentation of the root canal through the fracture line and long‐term calcium hydroxide treatment were carried out. One year later the radiograph indicated repair of the fracture with hard tissue. The tooth was then obturated with guttapercha and Grossman's sealer and restored with an acid–etch resin technique. At the 12‐month follow‐up examination the tooth was functionally and esthetically normal. Radiographically, the fracture line was not discernible and repair of the apical periodontitis had taken place.
Healing of apical periodontitis after endodontic treatment using three different root canal sealers
Authors: Eriksen Harald M. , Brstavik Dag , Kerekes Kasmer
Published: April 2006

Abstract In this study 3 commonly used sealers were evaluated. The materials tested were Proco‐Sol, a zinc oxide‐eugenol‐based sealer, AH26, an epoxy resin, and Klorperka NØ, a resin‐gutta‐percha‐chloroform sealer. The healing of periapical lesions was followed for a period of 3 years. While the response to Kloroperka NØ seemed slightly inferior to the 2 others, no statistically significant differences among the groups could be demonstrated.