bluuebunny/crossref_metadata_2025 huggingface dataset:
Histochemistry of the keratohyalin granules in human oral leukoplakia
Authors: Singh Baldev , McKinney Ralph V. , Kolas Steve
Published: April 2006

Abstract: The keratohyalin granules from 25 human oral leukoplakias, showing benign hyperorthokeratosis histologically, were examined employing a series of histochemical techniques. The tissues were fixed in 10% neutral buffered formalin, 80% methanol, or Carnoy's fluid. The keratohyalin granules stained intensely with Pauly's reagent, Congo red and Harris hematoxylin, indicating the presence of proteins. This was confirmed by abolishing the staining reaction by pretreatment with proteolytic enzymes. The keratohyalin granules also reacted with methyl green‐pyronin by staining pink at their peripheries; this staining was abolished by pretreatment with ribonuclease, indicating the presence of ribo‐nucleotides. The keratohyalin granules partially stained with toluidine blue and colloidal iron, indicating the presence of acidic polysaccharides. The keratohyalin granules did not react with the Feulgen reagent, suggesting the absence of DNA. Our studies indicate that the keratohyalin granules in human oral leukoplakia are primarily protein(s) complexed with polyribonucleotides. The presence of a carbohydrate moiety suggests the possibility of a protein‐polysaccharide component in the granules.
Torulopsis glabrata infection in the oral cavity
Authors: Hase M. P. , Radden B. G. , Reade P. C.
Published: April 2006

The first case report of an oral infection due to Torulopsis glabrata is presented. This microorganism is a yeast‐like fungus grouped in a similar family to the Candida species. It has been isolated with increasing frequency from the oral cavity but, surprisingly, has not been reported as a pathogen in this site. In other anatomical sites, including the urinary tract, lung and gastrointestinal tract, Torulopsis glabrata has been reported as a pathogen, at times resulting in a fatal outcome. However, there has usually been some modifying factor, e. g. malignancy, cytotoxic drug therapy, diabetes or broad spectrum antibiotics, which caused this marginal pathogen to assume a pathogenic role. No such modifying factors could be elicited in this case.

The history of the case including the management is presented. A brief outline of the microbiologic grouping of Torulopsis glabrata is given, as well as the diagnostic test used in its identification. The histopathology is described and the necessity for combining special tests in establishing a positive diagnosis is exemplified, as the histology alone is not pathognomonic of the infection.
Ultrastructural features of the verruciform xanthoma
Authors: Cobb Charles M. , Holt Robert , Denys Francis R.
Published: April 2006

The verruciform xanthoma, a rare lesion of the oral cavity, was studied by light and electron microscopy. The major cell type associated with the lesion was shown to contain appreciable amounts of lipid and was characterized as a macrophage. It was characteristic of the endothelial cells associated with subepithelial capillaries to exhibit multiple basal laminae. A rather unusual observation was the migration of lipid‐filled cells into the stratum germinativum of the overlying epithelium.
Tooth eruption and bone resorption: experimental investigation of the ia (osteopetrotic) rat as a model for studying their relationships
Authors: Marks Sandy C.
Published: April 2006

The osteopetrotic (ia) rat was examined as an experimental model for studying the dependence of tooth eruption on bone resorption. In ia rats eruption of incisors and first molars was rare and eruption of second and third molars was reduced and delayed. Autoradiographic studies of 3H‐proline incorporation showed that delayed eruption was not due to reduced tooth formation. Microscopic study revealed distortion and failure of posterior growth of the apical ends of incisors, unresorbed bone blocking the eruption pathway for molars, and ankylosis of incisors and first molars to alveolar bone. A reduction in bone resorption, known to be the primary cause of the disease in ia rats, is presumed to be the cause of the delayed or unerupted dentition. The effectiveness of attempts to increase bone resorption in ia rats at an early age by injection of vitamin A and/or parathyroid extract or by parabiotic union with a normal littermate was determined by measuring their effect on the relative size of the tibial marrow cavity. Only parabiosis had a beneficial effect on bone resorption but surgical union could not be performed in animals young enough to affect eruption of incisors and first molars in ia parabionts. These results suggest that parabiotic union of neonatal rats should allow resorption to begin early enough to test the presumed dependence of tooth eruption on bone resorption.
Dinitrochlorobenzene contact hypersensitivity in the hamster cheek pouch
Authors: Mohammad AbdelRahim , Mincer Harry H.
Published: April 2006

Stimulation of cell mediated immunity has been reported to be effective in bringing about clinical regression of carcinomas. The purpose of this pilot study was to investigate the possibility of introducing cell mediated immunity into an experimental animal‐chemical carcinogenesis system (dimethylbenzanthracene‐hamster cheek pouch) to serve as a model for the study of immunotherapy of oral cancer in humans. Contact hypersensitivity to dinitrochlorobenzene (DNCB) was induced in 17 Syrian hamsters via the abdominal skin. After secondary application of the allergen to the cheek pouch, local gross and histologic characteristics indicative of delayed hypersensitivity were observed. Control animals that had received only a primary or a secondary challenge with DNCB essentially showed no change. This study demonstrates that the buccal pouch of the Syrian hamster is capable of manifesting contact hypersensitivity to DNCB.
The effect of long standing chronic mechanical irritation on the tongue of rats
Authors: Shteyer A. , Greenman S. , Lewin‐Epstein J.
Published: April 2006

The effect of long standing mechanical irritation of the tongue was studied in 100 young rats. This was effected by the protruding end of a twisted wire, ligated around the lower first molar and directed toward the latero‐ventral aspect of the tongue on one side, while the other side served as control. Groups of rats were killed after 3, 6, 9 and 12 months and the tongues were examined grossly and microscopically. Fibrous hyperplasia was observed in 48 % of tongues in the 3‐month group and increased to 79 % in the 12‐month group. Microscopically, epithelial changes were noted which included ulceration, acanthosis and hyperkeratosis. In no instance was dyskeratosis or any other malignant change noted.
An investigation concerning tumor cell antigenicity of hamster malignant melanoma utilizing heterologous antiserum
Authors: Gulmen Suleyman
Published: April 2006

Abstract. The antigenic potential of spontaneous malignant melanoma of the Syrian hamster was investigated. Antisera to the tumor were prepared in two groups of rabbits; one group was immunized with tumor homogenate material and the other with tissue cultured tumor cells. The antiserum was absorbed with normal hamster tissue extracts and serum to remove cross‐reacting antibodies. The presence of tumor specific antibodies was demonstrated using immunodiffusion and fluorescent antibody staining techniques. Tumor specific antiserum prepared in this manner gave a single precipitin line against tumor tissue in. gel‐diffusion tests, and showed specific staining of tumor cells in the fluorescent antibody test.
Hyalin Material Bounding Dystrophic Calcification in the Epithelial Lining of Odontogenic Cysts
Authors: Allison R. T.
Published: April 2006

Abstract Areas of dystrophic calcification present in the epithelial lining of two apical periodontal cysts have been shown to exhibit an outer layer of hyalin material. Similar calcific areas in the connective tissue walls do not show hyalin boundaries. Hyalin material has been found around muscle fibers present in the epithelial lining of a residual dental cyst. It is believed that the hyalin material is secreted by the epithelial cells and these observations are considered to be supporting evidence that hyalin bodies arise as an epithelial secretion.
Fine structural studies of radiation‐resistant human squamous cell carcinomas1
Authors: Penney D. P. , Johansen E. , Rubin P. , Averill K. , Walker S.
Published: April 2006

Abstract Squamous cell carcinomas of the oral cavity are relatively common lesions, and often can be controlled by radiation therapy. Recently, a series of these tumors has been encountered which did not respond positively to irradiation, necessitating subsequent extensive surgery. This report describes some fine structural changes which were observed in squamous cell carcinomas following exposure to x‐irradiation. In addition to the common, keratin‐forming differentiated cell, others which were observed were secretory‐like, undifferentiated and phagocytic cells. Undifferentiated tumor cells occasionally became incorporated, at least temporarily, as a component of the blood vessel wall, perhaps reflecting metastatic potentiality. It is proposed that irradiation may either increase potential avenues of tumor cell differentiation or inactivate inhibitors thereof.
Scanning electron microscopic examination of root after apicoectomy
Authors: ŠVejda J. , Brázda O.
Published: April 2006

Abstract The scanning electron microscope was used to examine resected areas of eight roots of human teeth extracted after long intervals following surgical procedures. Some resorption lacunae were observed in the areas with protuberances of newly formed cementum. In the lacunae, honeycomb‐like structures were found. On the resected surface, residues of ligaments and periodontal fibers, and in one of the specimens dentinal tubules with odontoblastic processes protruding above the surface were present.
Microscopic changes in rat tongue following experimental cryosurgery
Authors: Buch B. , Papert A. I. , Shear M.
Published: April 2006

Abstract Histological changes were studied in the rat tongue for varying periods of time up to 14 days following the application of a cryoprobe to the dorsal surface of rat tongue. Within minutes of the application, focal subepithelial vesiculation and hyperemia occurred. At 3 h there was evidence of damage to capillary walls, resulting in hemorrhage. Arterioles and venules were thrombosed and there were degenerative changes in the muscle layer of their walls. At 6 h ventral epithelium showed evidence of damage. At this stage vessel walls were pavemented with neutrophilic polymorphonucleat leukocytes (PMN) and some of the latter were seen in the vessel walls. At 24 h abundant PMN, many of them necrotic, were present in the vessel walls, apparently unable to pass through them. At 48 h numerous PMN were seen adhering to degenerating muscle fibers. By 4 days necrotic changes extended through the full thickness of the tongue, but concurrently it was observed that the larger thrombosed vessels were becoming recanalized. At 5 days repair by granulation tissue was taking place and at 6 days the vasculature was virtually reconstituted. By 14 days healing was complete.
Angiolymphoid hyperplasia with eosinophilia
Authors: Eveson J. W. , Lucas R. B.
Published: April 2006

Abstract Angiolymphoid hyperplasia with eosinophilia is a recently recognized lesion of skin consisting of atypical vascular proliferation and variable inflammatory cell infiltration. A case is described here of a similar lesion presenting as an intraoral swelling. In addition to showing the histological features generally associated with angiolymphoid hyperplasia with eosinophilia, the present case exhibited striking smooth muscle proliferation.
Lipofuscin in human tongue muscle
Authors: Dayan Dan , David Raffaele , Buchner Amos
Published: April 2006

Abstract In a study of 107 tongue specimens lipofuscin granules were found to be present in the Muscle fibers of 93 % of the cases. The pigment was not found in young individuals under the age of 18 years. The pigmented granules, which were stored in clusters of different sizes at the nuclear poles, were PAS‐positive, stained black or brown with the Masson‐Fontana procedure, black with Sudan black, and strong purple‐pink with Ziehl‐Neelson staining; yellow autofluorescene was emitted in ultraviolet light. The morphology, histochemical reactions and autofluorescence of the pigmented granules were characteristics of the endogenous lipid pigment described as lipofuscin. Statistical analyses indicated a direct correlation between increase in quantity and distribution of the pigment and increase in age (P=0.001), in both males and females. Accumulation of the pigment in the tongue with aging was found to be similar to that in the myocardium.
Fluoride action on acid resistance of unaltered human surface enamel
Authors: Jeansonne B. G. , Feagin F.
Published: April 2006

Abstract. Unaltered surface enamel of extracted human teeth was subjected to tests of resistance to dissolution in 10 mM acetic acid at pH 4.0 and 10 mM EDTA at pH 7.4 in a miniature continuous flow system. Fluoride in EDTA had no effect on enamel dissolution. Inclusion of 0.25, 0.50 and 5.0 mM NaF in the acid at pH 4.0 greatly increased the resistance of the enamel to dissolution. The 0.5 mM NaF in the acid almost instantly reduced enamel dissolution and the effect persisted through the 1 h experiments. These results suggested that the acid labile fluoride in plaque and tooth minerals may provide the primary beneficial effect of all types of enamel fluoridation.
Cryosurgery of major and minor salivary gland: A light microscopic evaluation in the Rhesus monkey
Authors: Natiella Joseph R. , Meenaghan Michael A. , Rosa Roberta A. , Bessette Russell W. , Gage Andrew W.
Published: April 2006

Abstract. The minor salivary glands in the hard palate and the submandibular gland of the Rhesus monkey were subjected to a liquid nitrogen, direct‐spray, one‐cycle freeze. A 4‐min freeze in the temperature range of –40°C to –60°C was used. The extent of tissue destruction was determined at intervals up to 1 year. Clinically relevant findings resulted and form the basis for subsequent studies by this group of investigators.
Pathologic study of periapical lesions 1. Periapical granulomas: clinical, histopathologic and immunohistopathologic studies
Authors: Yanagisawa S.
Published: April 2006

Abstract Seventy periapical granulomas were histopathologically examined. They were divided into four types: exudative, granulomatous, granule‐fibrous, and fibrous types. Clinicopathologically, those having marked lymphocytic infiltration were found more frequently in cases having had endodontic treatment; further, the size of a radiolucent area did not exceed that of the involved tooth crown. In contrast, a predominant plasma cell infiltrate was more frequent in cases with open pulp chambers (no treatment). In those cases, the radiolucent area was larger than the crown. Foci with very large radiolucent areas were often of the exudative type. Epithelial proliferation was more frequent in cases without treatment. These findings indicate that endodontic treatment not only stops invasion of injurious factors but also proliferation of epithelium. Furthermore, in frozen sections of 26 granulomas, IgE‐containing cells and IgG and C3 fluorescence in the connective tissue were often observed. It appears that IgE‐mediated reaction and antigen‐antibody complexes may play a role in periapical pathosis.
Comparison of fluorescent antibody technique and conventional staining methods in diagnosis of cervico‐facial actinomycosis
Authors: Happonen R.‐P. , Viander M.
Published: April 2006

Eight formalin‐fixed and paraffin‐embedded biopsies with a histopathology suggestive of actinomycosis, were tested with fluorescent antibody technique using antiserum specific against Actinomyces israelii. The method was found effective even in decalcified tissue material. Positive fluorescent staining resulted, not only in the colonies but also in the surrounding cells, suggesting the presence of intracellular Actinomyces antigens. The possibility of retrospective biopsy study is very helpful in cases of prolonged infections. Grocott's stain was found to be most effective conventional method for screening suspected actinomycosis.
Histological study on the origin of dentinal immunoglobulins and the change in their localization during caries
Authors: Okamura K.
Published: April 2006

At the incipient stage of the caries process prior to destruction, immunoglobulins were first localized in the odontoblast layer in spite of absence of plasma cells in the pulp, and secondly located in the dentinal tubules of the pulpal side of dentin. When the tooth became involved, caries immunoglobulins were localzed under the lesion Bovine serum albumin, which was administered on tooth surfaces, was not observed in the non‐decayed area of dentin. When injected into blood vessels, the protein was found in both decayed and unaffected dentin. It is suggested that, at the incipient stage of the caries process, dentinal immunoglobulins come from the pulp, although the possibility of salivary origin at a later stage is not excluded; and that immunoglobulin localization changes during the caries process.
Immunohistochemical localization of amylase in sialoadenitis and salivary gland tumors
Authors: Sumitomo S. , Kumasa S. , Tatemoto Y. , Ookusa Y. , Mori M.
Published: April 2006

Immunohistochemical demonstration of α‐amylase has been made in sialoadenitis‐involved tissue and salivary gland tumors, as well as in normal salivary glands. Immunoreactive α‐amylase with trypsin pretreatment was confined to irregularly staining serous acinar cells in the parotid and submandibular glands, and to demilunes in subligual glands. In obstructivce adenitis, staining was irregular from high to negative in acini in early or intermediate stages. Dilated ductal segments contained cells positive for α‐amylase in the early stage following obstruction. Pleomorphic adenomas were usually negative for α‐amylase but in rare cases tumor epithelia stained variably positive; i.e., staining occurred throughout the cytoplasm or at the periphery or apical part of the tumor cells. Luminal cavities of tubular and duct‐like structures contained α‐amylase‐positive material. Epithelia in Warthin's tumor were also negative in general; however, scattered single or grouped tumor cells containing α‐amylase were found. Mucoepidermoid tumors were also negative, though slightly positive cells were found intermingled among the negative squamous and mucous tumor cells. Cystic lesions in mucoepidermoid tumor were sometimes positive in the wall cells together with material secreted into the lumen.
Effectiveness and safety of a sonic vibratory endodontic instrument
Authors: Tronstad L. , Barnett F. , Schwartzben L. , Frasca P.
Published: April 2006

Abstract An air‐driven sonic vibratory handpiece to which specially designed K‐type files are attached has been developed. When activated, the root canal instruments will vibrate in a whirling motion, and when moved up and down, will abrade the root canal wall. The sonic system was tested in simulated root canals in plastic blocks and in usage tests in dogs' teeth. Forty‐nine roots in 3 dogs were divided into 3 groups. Two of the groups were instrumented with the sonic device under continuous irrigation with 2.5% NaOCl or 15% EDTA. The 3rd group was treated with conventional chemomechanical instrumentation and 2.5% NaOGl. The teeth were then extracted, fixed and split in a longitudinal direction and the root canals examined in the scanning electron microscope. After hand instrumentation and sonic instrumentation using NaOCl for irrigation, the canal wall was covered by a smear layer and dentin chips and occasional tissue remnants were seen. An extraoral fine mist of NaOCl was seen during continuous irrigation with this medicament, causing eye soreness in the operator. Continuous irrigation with EDTA during sonic instrumentation removed the smear layer and gave clean canal walls. The vibratory files appeared safe and size 20 followed curved canals well. The effectiveness of the sonic device was similar to hand instrumentation. It considerably improved the ease and, to some extent, the speed of root canal instrumentation.
Controlled release of medicaments in endodontic therapy
Authors: Tronstad Leif , Yang Zu‐Pyn , Trope Martin , Barnett Frederic , Hammond Benjamin
Published: April 2006

Abstract It was the purpose of this investigation to study the suitability of a controlled release delivery system for endodontic medicaments, making it possible to maintain a constant concentration of a medicament in the root canal for an extended period of time. The delivery system comprised an inner core matrix containing the medicament surrounded by a polymeric membrane allowing a controlled release of the active ingredient. Controlled release preparations containing formocresol, camphorated paramonochlorphenol, Creation, and a quaternary ammonium compound (dodecyl‐dimethyl‐benzylammonium chloride) were manufactured and applied to root canals of dogs' teeth. In control experiments the same medicaments were applied to root canals by means of cotton pellets. After 1, 3, 7 and 45 clays the pieces of polymeric materials and the cotton pellets were removed from the root canals and tested for antibacterial effect. After 1 d in the root canal none of the medicaments on cotton pellets had an effect. Of the controlled release preparations, the quaternary ammonium compound had a fairly constant effect on bacterial growth for the duration of the experiment (45 d). The results suggested that the idea of improving the effect of endodontic medicaments by means of controlled release delivery systems is valid, and may gain clinical importance in the future.
Accuracy of an electronic apex locator under controlled clinical conditions
Authors: Trope Martin , Rabie Geoffrey , Tronstad Leif
Published: April 2006

Abstract Clinical guidelines essential for accurate use of the electronic apex locator were developed. Common causes for inaccurate readings are described as well as ways to minimize inaccuracies. While strictly adhering to the developed clinical routines, the apex locator was used in a controlled experiment. The lengths of 127 root canals in human teeth, irrespective of diagnosis, were measured. With the instrument placed at the apical foramen, as assessed by the apex locator, a radiograph was taken with a parallelling technique. In 90.6% of the canals the tip of the instrument was assessed to be within 0.5 mm of the radio‐graphic outline of the tooth. In 7% of the canals the instrument was 1 to 2 mm short. Only 2.4% of the instruments were up to 1 mm long. Under the strict clinical guidelines used, the apex locator was (bund to be a valuable aid both in routine endodontic treatment and in special clinical situations where the use of radiographs was not feasible.
Surgical access for endodontic treatment of intruded teeth
Authors: Tronstad Leif , Trope Martin , Bank Malcolm , Barnett Frederic
Published: April 2006

Abstract This case report describes the first phase in the treatment of an 11‐year‐old patient with completely intruded maxillary central incisors. The intruded teeth were left to spontaneously re‐erupt. After 10 days, the crowns of the teeth were exposed surgically for the initiation of endodontic therapy and an aqueous paste of calcium hydroxide was placed in the root canals. Eight wk after the injury and 6 wk after the endodontic treatment was initiated, the intruded incisors had re‐erupted to about their original position before the displacement occurred.
Effect of transcutaneous electrical nerve stimulation on pain perception threshold and pain tolerance level of human teeth subjected to electrical stimulation
Authors: Rooney Jane , Tronstad Leif
Published: April 2006

Abstract The effect of low current, sub‐sensation transcutaneous electrical nerve stimulation on pain threshold and pain tolerance level of human teeth subjected to stimulation with an electrical pulp tester was studied. Electrodes were attached to the patients via a patch between the thumb and first finger and a damp cotton roll in the vestibule over the apex of the tooth to be tested. No significant differences between the values for the baseline, experimental and placebo pain perception thresholds were found. Nor were significant differences found between the average experimental and placebo values concerning pain tolerance level. However, in 1 individual the pain tolerance level was not reached at the highest level of stimulation from the electrical pulp tester.
Book Review
Authors: Pliskin Michael
Published: April 2006

J. J. Pindborg: Atlas of Diseases of the Oral Mucosa. Philadelphia: W. B. Saunders Company, 1985.
Interobserver variation in radiographic examination of endodontic variables
Authors: Eckerbom Mats , Andersson Jan‐Erik , Magnusson Tomas
Published: April 2006

Abstract A study was made of the interobserver variation between 2 observers surveying a) the frequency and b) the technical standard of endodontic treatment. The material consisted of 20 sets of full‐mouth radiographs. Before the examination the observers were calibrated and strict criteria were defined. The agreement between the 2 observers was high for most of the variables studied and superior to that found in several previous investigations. While interobserver errors may be impossible to avoid in interpretation of endodontic treatment from dental radiographs, it is concluded that they may be reduced by calibration of observers and by establishing strict criteria for evaluation.
The effect of ultrasonic root canal preparation on inflammatory root resorption
Authors: Lindskog Sven , Berg Jan‐Olov , Pierce Angela
Published: April 2006

Abstract In recent years, ultrasonic endodontic instruments have been used for the cleansing and disinfecting of root canals. In the present study, inflammatory root resorption, itself an indication of the presence of bacteria in the dental root, was experimentally induced in monkey teeth. Root canals were subjected to ultrasonic endodontic preparation in order to investigate the antibacterial effects of this treatment method on the pulpal and periodontal tissues in vivo. Results were histologically evaluated using a morphometric technique, and revealed that ultra‐sonication eliminated bacteria and inflammatory root resorption. Furthermore, it had no damaging effects on a healthy periodontal membrane. It is suggested that this mode of treatment may be of value in the elimination of bacteria inside those dentinal tubules otherwise inaccessible to conventional therapy.
Periodontal ligament anesthesia — A clinical evaluation
Authors: Eriksen Harald M. , Aamdal Hilde , Kerekes Kasmer
Published: April 2006

Abstract Periodontal ligament (PDL) injection was used either as an alternative or as a supplement to conventional anesthesia techniques (CA) in connection with endodontic treatment of 339 teeth. Adequate analgesia was obtained more frequently with CA than with PDL. However, total lack of effect was registered only in a few cases for both techniques. PDL was found to be of particular value in the mandibular posterior segments where conventional techniques most frequently failed.
Endodontic decision‐making under uncertainty: A decision analytic approach to management of periapical lesions in endodontically treated teeth
Authors: Reit Claes , Gröndahl Hans‐Göran
Published: April 2006

Abstract Management of periapical lesions in endodontically treated teeth is subject 10 considerable interexaminer variation. This uncertainty can be approached by using formal decision analysis. Temporal and logical display of decision alternatives, values of probabilities and utilities of various outcomes arc tin‐features of such an analysis. The present study deals with two endodontic cases in which probability values were provided by two groups of examiners (general practitioners and endodontists) through the Delphi group opinion technique. Utility values were determined by the authors. For each decision alternative, a so‐called expected value could be calculated by multiplying values of probability and utility. The expected values are proposed to act as guidelines for the selection of optimal decision strategy.
Coronal fracture of an unerupted incisor
Authors: Mackie Iain Campbell
Published: April 2006

Abstract A case is reported of a girl who fell when she was 5 yr old and, as a result of the fall, her unerupted upper right permanent incisor suffered a coronal fracture due to a penetrating injury of the alveolus. The tooth subsequently failed to erupt and had to be surgically removed.
Effect of pulpal inflammation on bacterial penetration of acid‐etched and non‐etched dentin
Authors: Tziafas Dimitrios , Kolokuris Ioannis
Published: April 2006

Abstract Bacterial invasion of acid‐etched and non‐acid‐etched dentin was compared in teeth with intact pulps and in teeth with experimentally induced pulpal inflammation. In 37 pairs of teeth from 3 dogs, class V cavities were prepared. In 1 tooth from each pair, pulpal inflammation was induced by the application of a strong thermal irritant to the floor of the cavity. In 18 pairs of teeth the cavity floor was treated with orthophosphoric acid, and in 19 pairs with normal saline. The cavities remained open to oral microflora for a period of either 3 or 7 d. All the teeth with acid‐etched dentin and only 9 teeth with non‐acid‐etched dentin exhibited slight invasion of the dentinal tubules by gram‐positive or gram‐negative bacteria. This invasion had no relationship to the histopathological findings in the pulp
Partial pulpotomy as a treatment alternative for exposed pulps in crown‐fractured permanent incisors
Authors: Fuks Anna B. , Chosack Aubrey , Klein Hortense , Eidelman Eliecer
Published: April 2006

Abstract Sixty‐three vital permanent incisors with complicated crown fractures were treated by partial pulpotomy and assessed clinically and radiographically for healing. Healing of the pulp was considered to have taken place when the following criteria were fulfilled: absence of clinical symptoms, radiographic evidence of dentin bridge formation, no intrapulpal or periapical pathosis, continued root development in immature teeth, and a positive response to electrical pulp testing. The treatment was successful in 59 teeth (94%). In the remaining 4 teeth, necrosis of the pulp was diagnosed clinically and radiographically 3 weeks to 6 months after treatment. The high frequency of healing in both the present and previous studies seems to justify recommending partial pulpotomy as the treatment of choice in crown‐fractured teeth with pulp exposure.
Occurrence of pulp canal obliteration after luxation injuries in the permanent dentition
Authors: Andreasen Frances M. , Zhjie Yu , Thomsen Birthe Lyhke , Andersen Per Kragh
Published: April 2006

Abstract A material of 637 concussed, subluxated, extruded, laterally luxated and intruded permanent incisors was analyzed with respect to factors influencing the development of pulp canal obliteration (PCO) after injury. A total of 96 (15%) developed partial PCO; 9 of these (1% of the total material) went on to develop total PCO. Only 2 teeth exhibited yellow discoloration of the clinical crown and 1 showed grey discoloration. Sensibility to electrometric pulp testing of the teeth with PCO was not significantly different from sensibility of contralateral homologues at the final examination (except for after lateral luxation, where the teeth with PCO had a significantly lower perception threshold). PCO was significantly more frequent among teeth with incomplete root formation than in teeth where root formation was completed. Extrusion, lateral luxation and intrusion showed more frequent occurrence of PCO than did concussion and subluxation. Moreover, the use of orthodontic band/resin splints significantly increased the occurrence of PCO, presumably due to the additional trauma of forceful placement and cementation of orthodontic bands in contrast to the relatively passive placement of an acid‐etch/resin splint. Based on previous and present clinical and radiographic findings concerning pulp response to luxation injuries, it is suggested that PCO is a sequel to revascularization and/or reinnervation of a damaged pulp after injury.
Lateral root dilaceration: a multi‐disciplinary approach to treatment
Authors: Mattison Gordon D. , Bernstein Mark L. , Fischer John W.
Published: April 2006

Abstract This Case report illustrates the importance of coordinating various dental specialties in the successful treatment of the traumatized patient. The patient sustained multiple traumatic injuries to the anterior maxilla in the primary and permanent dentition stages of development. Orthodontic considerations involved in this case included an unerupted maxillary right central incisor with dilaceration of its root, severe malocclusion, and compromised esthetics. Endodontic concerns were directed toward the traumatized primary and permanent maxillary incisors with subsequent devitalization of the maxillary right permanent central incisor and calcification of the maxillary left permanent incisor. Oral surgery, oral pathology and general dentistry were also involved throughout the course of treatment.
Causes and types of traumatic tooth injuries treated in a public dental health clinic
Authors: Oikarinen Kyösti , Kassila Dili
Published: April 2006

Abstract A total of 1152 patients under 20 yr of age with 1611 accidentally traumatized teeth treated at the Helsinki Health Center oral surgery clinic in 1979 and 1980 were studied with respect to the etiology, type, extent and severity of their injuries. The mean age of the patients was 11 yr and the male: female ratio was 2.7:1. The prevalence was highest in the age group 7‐10 yr for girls and in the age group 11–15 yr for boys. More injuries were recorded as having taken place outside school or kindergarten and in the fall and winter months. Most of the injuries were exclusively hard tissue traumas; 81% were estimated as mild, 15% as moderate, and only 4% as serious and needing specialized treatment. Typical causes were accidents at school (28%) or at home (27%), while only 11% were traffic accidents, 21% were due to sports and 11 % due to acts of violence. These last three etiologies were more common among the boys (p< 0.001). Violence was the main etiology for tooth injuries among patients aged 16–20 yr (p<0.001), resembling the findings regarding causes of facial bone injuries. The proportion of home or school accidents seemed to be decreasing in relation to traffic and sports accidents, which were more numerous in 1980 than in 1979. Most accidents were single‐tooth injuries, but the youngest and oldest age groups involved more cases of 3 or more simultaneous tooth traumas than did the other age groups.
Pathogenesis and mechanism of traumatic injuries to teeth
Authors: Oikarinen Kyösti
Published: April 2006

Abstract Type of tooth injury is determined by the energy and direction of impact, as well as by the resilience and shape of the offending object. A total of 1611 traumatized teeth in 1152 patients were examined to investigate differences in injury patterns in relation to the etiology and mechanism of injury. The injuries were divided into mild, moderate and serious, and into hard tissue injuries, periodontal tissue injuries, or injuries involving both types of tissue. The mechanisms were divided into four categories describing the energy, shape and resilience of the offending object. Seven etiological categories were recognized. The numbers of teeth injured simultaneously differed between accidents (p< 0.01), with violence and traffic accidents causing multiple injuries more frequently than sports or undefined accidents at home or at school, which were more often single‐tooth traumas. Injuries due to traffic accidents were estimated as serious more often than those of other etiologies. Individual sports accidents resulted in more hard tissue injuries, while violence caused more periodontally injured teeth. Numbers of teeth injured simultaneously and types of injuries differed according to the mechanism of the trauma (p< 0.05 and p< 0.001 respectively). A resilient surface or resilient object resulted less often in single tooth injuries than a hard surface or hard object, but more often in periodontally injured teeth.
Endodontic treatment of experimentally induced apical periodontitis in dogs
Authors: Allard Urban , Strömberg Ulla , Strömberg Torsten
Published: April 2006

Abstract A total of 44 roots with periradicular inflammation, induced by inoculation of Streptococcus faecalis, were treated endodontically. All root canals were prepared with K‐reamers using 0.5% solution of sodium hypochlorite for irrigation. Bacteriological specimens demonstrated growth in all teeth when the root‐canal fillings were made. In all, 22 roots were filled with gutta‐percha, 11 roots with a calcium hydroxide preparation (Cala‐sept®) and 11 roots with Calasept®+ Dionosil®, an iodinized radio‐graphic contrast medium. The addition of Dionosil® improved the possibility of evaluating the placement of the calcium hydroxide paste. Dressings with calcium hydroxide are recommended in the treatment of teeth with apical periodontitis.
Frequency and technical standard of endodontic treatment in a Swedish population
Authors: Eckerbom Mats , Andersson Jan‐Erik , Magnusson Tomas
Published: April 2006

Abstract The purpose of this investigation was to study the frequency and technical standard of endodontic treatment in a Swedish population. The material consisted of full‐mouth radio‐graphic surveys from 200 patients treated by general practice dentists, and the radiographs were analyzed by two observers. Thirteen percent of the teeth had been endodontically treated. Periradicular radiolucencies were found in 5.2% of the teeth and 26.4% of the endodontically treated teeth had such periradicular radiolucencies. In nearly half of the root‐filled teeth, the root filling ended more than 2 mm from the apex, and only 56.3% were judged to have a proper seal. It is concluded that the need for endodontic treatment is great and the technical standard of the root fillings is poor. This strongly indicates that there is a need for standardized endodontic treatment methods and for more specialists in endodontics in Sweden.
Neurotoxic and analgesic effects of root canal cements and pulp‐protecting dental materials
Authors: Brodin Pål
Published: April 2006

Abstract Root canal cements have been associated with paraesthesia of the inferior alveolar nerve after contact between the nerve and the sealer. A survey of the literature shows that more than 40 such cases have been reported in the past 2 decades. Most of these patients have been treated with materials that either contain (para) formaldehyde or develop formaldehyde during setting. It seems likely that neurotoxic effects of the sealers may cause the paraesthesia. Irreversible destruction of nerve excitability has been found in vitro after nerve contact with sealers based on zinc oxide‐eugenol (ZEO) cement containing formaldehyde, and with calcium hydroxide (Ca(OH)2). Moreover, some nerves may also be permanently damaged after contact with Kloroperka N‐O or regular ZOE cement. A neurotoxic potential has also been found for Diaket, AH26, ProcoSol, and Dycal. Ca(OH)2‐containing preparations are probably toxic due to their high pH and an excess of Ca++ ions, whereas neurotoxicity of Kloroperka N‐O is related to its chloroform content. In more detailed studies of its effects on nerve and muscle membranes, eugenol showed similar characteristics as local anaesthetic drugs, explaining the analgesic effect of eugenol. At concentrations above 2.4 mM, eugenol irreversibly inhibited the nerve conduction. In similar studies on formaldehyde, multiple action sites on nerve and muscle membranes could be demonstrated, and at concentrations above 8.9 mM nerve excitability became permanently impaired. Such high concentrations may be reached in patients due to the high solubility of paraformaldehyde in water. Thus, of the reported cases of paraesthesia following root canal treatment, one case caused by ZOE was reversible, but those caused by ZOE‐based sealers containing formaldehyde were irreversible unless surgical treatment was performed (22 out of 25 cases).
Incidence of external root resorption and esthetic results in 58 bleached pulpless teeth
Authors: Friedman Shimon , Rotstein Ilan , Libfeld Harry , Stabholz Adam , Heling Ilana
Published: April 2006

Abstract Fifty‐eight bleached pulpless teeth were re‐examined after periods of 1–8 years. Recall examination included recording of the esthetic results, clinical findings and radiographs. External root resorption was found in 4 of the cases (6.9%), and was progressive in 2 cases and arrested in 2 cases. There had not been any pre‐ or postoperative trauma in any of the 4 cases. The occurrence of resorption was not related to the bleaching technique used. Resorptive lesions were found to have been initiated apical to and not at the cemento‐enamel junction. Esthetically, the bleaching was considered successful in only 50% of the cases, acceptable in 29% and failed in 21%. These results caution against indiscriminate use of bleaching with hydrogen peroxide, and emphasize the importance of preventive measures and postoperative follow‐up of bleached pulpless teeth.
Pulpal reactions following experimental acute trauma of concussion type on immature dog teeth
Authors: Tziafas Dimitrios
Published: April 2006

Abstract The pulpal reactions of 14 immature incisors of two dogs were histopathologically evaluated 45 days after experimental mechanical blows that did not, as shown by post‐traumatic clinical examination, cause fracture, displacement or loosening of the teeth. The more significant pulpal reactions in all specimens were the coagulation necrosis of the coronal pulp and the hyalinization of the central region of the radicular pulp. Dystrophic calcifications within coronal or radicular necrotic tissue, and absence of inflammatory infiltration were also observed in all traumatized teeth.
Periodontally derived pulpal lesions
Authors: Dongari Anna , Lambrianidis Theodor
Published: April 2006

Abstract Concurrent pulpal and periodontal disease has been described as the outcome of the pathogenetic interactions between the pulp and the periodontium. Although the existence of primary endodontic lesions with secondary periodontal involvement, as well as that of “true” combined ones has been undoubtedly justified, some controversy and confusion still exist over primary periodontal lesions with secondary endodontic involvement. In this article, theoretical communicable pathways between pulp and periodontal ligament, which can be responsible for the extension of the primary periodontal inflammatory lesion in the pulp, are described. Furthermore, a re‐evaluation of the pulpal invasion phenomenon is presented, based on recent research and clinical findings that demonstrate that no constant relationship between the depth of the periodontal pocket and the status of the pulp has ever been found.
A comparison of the effects of cresol and eugenol on bovine pulp
Authors: Ranly Don M. , Garcia‐Godoy Franklin , Horn Diane
Published: April 2006

Abstract Bovine pulp was treated in vitro with saline, cresol, or eugenol and analyzed morphologically, histologically, and biochemically. Cresol caused considerable shrinkage and disruption of tissue compared to saline and eugenol‐treated samples. Cresol also extracted more phospholipids, as determined chemically, and more phospholipids and neutral lipids as visualized by chromatography. The extraction of phospholipids by saline and eugenol was very similar. Neutral lipid extraction by eugenol was limited. It was concluded that cresol caused more dehydration of pulp tissue and considerably more dissolution of cell membranes than eugenol.
Local injection of Benadryl® for the prevention of iatrogenic endodontic flare‐ups
Authors: Nevins Alan , Friedman Lee , DeVita Richard , Schacter William
Published: April 2006

Abstract Endodontic flare‐ups often occur within 24 h of root canal debridement, during which time a small amount of antigen in the form of necrotic pulp tissue and bacteria within the root canal, may be inadvertently extruded through the apical foramen. Subsequently, preformed mediators such as histamine are released into the tissue, causing symptoms of pain and swelling. The IgE‐mast cell mechanism conceivably plays an important role in this development. A rationale for using local injection of Benadryl® prior to canal debridement of infected teeth is given, along with an indication of a lack of adverse reactions and side effects following such treatment.
Dens evaginatus in the Hong Kong Chinese population
Authors: Bedi Raman , Pitts Nigel B.
Published: April 2006

Abstract A survey was conducted to determine the prevalence and treatment need of permanent teeth with an evaginated odontome in a random sample of 12‐year‐old Chinese schoolchildren living in Hong Kong. A total of 442 12‐year‐old Hong Kong Chinese schoolchildren were examined (215 males and 227 females); 15 children (3%) had teeth with evaginated odontomes present. Males were more commonly affected than females (9:6) and no left‐to‐right difference was detected. In 8 children there was bilateral involvement of collateral teeth. Over twice as many mandibular premolars were affected compared to those in the maxilla (27:11). Guidelines for future epidemiological surveys of this anomaly are discussed. The management of dens evaginatus is based upon empirical evidence and there has, to date, been no controlled clinical trial conducted to evaluate the effectiveness of any particular type of treatment for this anomaly. In the absence of objective evaluation, results are reported of a survey of the approaches of managing dens evaginatus used by general dental practitioners working in Hong Kong.
Prevalence and quality of endodontic treatment in an urban adult population in Norway
Authors: Eriksen Harald M. , Bjertness Espen , Brstavik Dag
Published: April 2006

Abstract There are few studies on the prevalence of chronic apical periodontitis and endodontic treatment in society. In this study, the periapical status of a representative sample of 35‐year‐olds in Oslo, Norway was studied by analyses of orthopantomograms and intraoral radiographs. The study also included quality assessment of root fillings and a correlation between quality and periapical status. Of the 3917 teeth evaluated, 133 (3.4%) were endodontically treated and 54 (1.4%) presented a periapical pathosis. More than half of these were associated with root‐filled teeth. Endodontic treatment was considered successful with normal periapical structures in 64% of the cases. However, only 41% of the root fillings were of optimal quality, terminating 1–2 mm from the radiographic apex. Based on a survey of orthopantomograms, it was estimated that 30% of the subjects investigated presented an endodontic treatment need. The prevalence of endodontic treatment among 35‐year‐olds was unchanged from 1973 to 1984.