bluuebunny/crossref_metadata_2025 huggingface dataset:
Oral defense factors in the elderly
Authors: Tenovuo Jerma
Published: April 2006

Abstract Continuously increasing proportion of elderly people in the human population creates new challenges for the dental care. Because the microbial etiology of the most common oral diseases, dental caries, endodontal and periodontal diseases, is not substantially different in different age groups, the altered host response during aging may modify the progression of these deseases. Most prevalent and severe change in the oral defense is hyposalivation or xerostomia but aging as such does not seem to reduce neither parotid nor whole salivary flow rate. However, submandibular and minor salivary glands produce less saliva at old age which may be the reason for the frequently reported symptoms of oral dryness even if the stimulated flow rate is normal. Concomitantly to the changes in the flow rate the daily output of many saliva‐mediated defense factors declines but age‐related impairment has been described only for specific I gA response to external antigens, for salivary opsonic activity, and for T‐lymphocyte function The non‐immunoglobulin defense factors seem to act with full capacity over the entire life‐span. Therefore, elderly people with normal salivary flow rate possess no special risk group for the development of oral diseases.
Effectiveness of different endodontic files for preparing curved root canals: a scanning electron microscopic study
Authors: Zmener O. , Marrero G.
Published: April 2006

Abstract In this study, the effect of using four endodontic files from different manufacturers on the final shape of 80 prepared curved root canals of extracted single‐rooted teeth were comparatively analyzed with scanning electron microscopy. The instruments tested were Tri‐files, Flex‐R files, Flexofiles and conventional K‐type files. All files were used with in and out linear movements with a circumferential motion starting with a size 15 file. Final preparation of the apical thirds was performed with a size 30 file. Shaping effectiveness of the tested files was qualitatively evaluated in terms of respect for conservation of the apical constriction and the presence or absence of ledging, specially in the apical third of the root canals. A well‐centered and tapered preparation without apical transportation or ledging was detected when Tri‐file or Flex‐R files were used. Conversely, the use of Flexofile or conventional K‐type files resulted in frequent alteration of the initial pattern of the root canals, showing an hourglass preparation with alteration of the apical constriction and ledge formations.
Toxic effects of various retrograde root filling materials on gingival fibroblasts and rat sarcoma cells
Authors: Peltola Matti , Salo Tnula , Oikarinen Kyösti
Published: April 2006

Abstract The aim of this in vitro study was to evaluate the effect of amalgam, glass ionomer, composite and titanium on the growth of gingival fibroblasts (GF) and rat sarcoma cells (UMR) in vitro. The cells were either obtained from gingival biopsies taken during deliberation of unerupted canines (GF) or were of commercial origin (UMR). Equal numbers of cells were placed on culture dishes and incubated for a period of two weeks with the freshly prepared test materials. The cultures were photographed through a light microscope after 7 days incubation and finally counted after 14 days. It was shown that the proliferation of gingival fibroblasts was less disturbed by titanium, being approximately 96% of the control value (cell cultures without lest particles), followed by composite, amalgam and glass ionomer (61%, 49% and 35% of the control value respectively). The number of UMR cells after 14 days incubation with the various materials was 76% of the control value with titanium, 12% with composite and 5% with both amalgam and glass ionomer. Inhibition of cell growth (UMR) around the test particles was most prominent around amalgam and glass ionomer, followed by composite and titanium. These effects were noted only with freshly prepared components however, so that the toxic reaction was less pronounced or minimal in a second incubation using the same particles sterilized in between. The results demonstrated that potential retrograde root filling materials have a variable toxic effect on gingival fibroblasts and rat sarcoma cells. The fact that the influence on proliferation disappeared when the test was performed with materials already tested once may be of clinical importance when estimating the biocompatibility in vivo.
Apical closure of an immature root subsequent to apical curettage
Authors: Ohara P. K. , Torabinejad M.
Published: April 2006

Abstract A 7‐year‐old female presented with a history of trauma to the mandibular central incisor resulting in pulpal necrosis and soft tissue swelling. During apexification treatment, an ultrasonic file was separated and lodged in the periapical tissues. Surgical retrieval of the broken instrument resulted in complete curettage of the periapical tissues. Apical closure occurred following intracanal calcium hydroxide therapy. The findings suggested that hard tissue barrier formation occurred despite the absence of Hertwig's epithelial root sheath and local periapical tissues.
Antibacterial effects of various endodontic irrigants on selected anaerobic bacteria
Authors: Ohara P. , Torabinejad M. , Kettering J. D.
Published: April 2006

Abstract This study was undertaken to determine the antibacterial effects of various endodontic irrigants against six selected anaerobic bacteria. The organisms were mixed separately with dilutions of each of the irrigants in lubes containing fluid thioglycollate broth and allowed to remain in contact for specific time periods before being evaluated for growth. Of the six irrigants tested, chlorhexidine appeared to be the most effective antibacterial substance. Hydrogen peroxide, sodium hypochlorite and REDTA were less effective while the calcium hydroxide and saline solutions proved to be totally ineffective.
Evaluation of the dimensional stability of different thermoplasticized gutta‐percha fillings using simulated glass root canals
Authors: Capurro M. A. , Goldberg F. , Balbachan L. , Macchi R. L.
Published: April 2006

Abstract The dimensional stability of different thermoplasticized gutta‐percha fillings was analyzed using simulated glass canals. For comparison, gutta‐percha fillings obtained with the cold lateral condensation technique was used. The evaluation was done at 0 min, 2 min, 5 min, and 30 min after the tilling was completed. The general analysis showed statistically significant differences between 0 min and 5 min–30 min recordings. No significant differences were found between 0 min and 2 min, and between 2 min, 5 min, and 30 min. Although warm lateral condensation resulted in a poor obturation, it was the only thermoplasticized technique analyzed that did not produce significant volumetric changes between 0 min and 30 min. All the other thermoplasticized filling techniques showed important shrinkage during cooling.
Effects of intracanal medicaments on inflammatory resorption or occurrence of ankylosis in mature traumatized teeth: a review
Authors: Vanderas A. P.
Published: April 2006

Abstract A review of the literature of the effect of intracanal medicaments on inflammatory resorption or occurrence of ankylosis in mature traumatized teeth is presented. The results of the studies show that calcium hydroxide and Ledermix paste eliminate inflammatory resorption. Other medicaments such as gutta‐percha with sealer, antibiotics, and calcitonin reduce or almost eliminate this complication. Ankylosis or replacement resorption develops in the root surfaces of teeth with mature roots irrespective of medicaments used. However, the percentage of relative surface area of the root which develops ankylosis is significantly higher in mature teeth treated with calcium hydroxide than in teeth treated with permanent root filling. Ledermix paste targets the resorbing cells without damaging neighbouring tissue. Recommendations for the use of calcium hydroxide and Ledermix paste as intracanal dressings in traumatized mature teeth are made.
Excretion of 14C‐formaldehyde distributed systemically through root canal following pulpectomy
Authors: Araki Kouji , Isaka Hideki , Ishii Toyohiko , Suda Hideaki
Published: April 2006

Abstract The fate and excretion of 14C‐labeled formaldehyde, when applied as formocresol in the root canals of cat's canines, was examined using a chamber apparatus for the collection of the cat's respiratory CO2. Six cats divided into two groups of three were used. Four μl or 8 μl of formocresol was applied per root canal. Seventy‐two h after formocresol application, the accumulated recovery rate of UGCX represented 21.9% of total dose in the 4 μl group and 35.4% in the 8 μl group. Samples were collected after 72 h from blood and urine, and from lung, liver and kidney tissue, 14C‐radioactivity was selected in all samples. The percentage of the total dose in each organ was very low and there was no significant difference between the 4 μl and 8 μl groups. These results suggested that when formocresol was medicated into the cat's canine canals following pulpectomy, formaldehyde was distributed in the body and rapidly metabolized and excreted.
Atypical apical lesions detected during a study of short‐term tissue responses to three different endodontic instrumentation techniques
Authors: Watts Andrew , Paterson Robert
Published: April 2006

Abstract An investigation is in progress using the beagle dog to investigate the short‐term responses of the supporting tissues to different methods of root canal preparation. Atypical apical lesions have been observed in 4/27 teeth examined 7–14 days after instrumentation. These lesions were related to the apical foramina and were characterized by total cellular destruction. The centres of the lesions had densely staining material which appeared to be either damaged collagen or nuclear fragments. PMNLs were present at the periphery. The exact aetiology of these lesions is uncertain at present. The possibility of a previously unreported tissue reaction to sodium hypochlorite is being investigated further.
Periodontal destruction and tooth loss following pulp devitalization with Toxavit: report of a case
Authors: Hülsmann Michael , Hornecker Else , Redeker Marianne
Published: April 2006

Abstract In density, paraformaldehyde‐containing substances are still used for the devitalization of the vital pulp. A clinical case report is presented describing the sequelae of vital pulp devitalization with the paraformaldehyde‐containing agent Toxavit. Marginal leakage of the temporary filling and iatrogenic perforation of the pulp chamber floor resulted in diffusion of the agent into the surrounding tissues with subsequent bone sequestration and loss of two teeth.
Dental injuries in association with mandibular condyle fractures
Authors: Silvennoinen U. , Lindqvist C. , Oikarinen K.
Published: April 2006

Abstract A total of 356 patients with mandibular condyle fractures were studied regarding associated dental injuries. One third of the patients had injured teeth, on average, 3.7 teeth had been injured per accident. Dental traumas were distributed equally between the anterior (incisors and canines) and posterior teeth (premolars and molars) in both jaws. In unilateral condylar fracture cases maxillary dental injuries involved more often premolars and/or molars of the fracture side than those of the non‐fracture side. The mean number of dental traumas in the mandible was higher in cases of simultaneous mandibular body fracture than without, whereas the presence of mandibular body fracture did not affect number of associated dental injuries in the maxilla. The dental injuries were mostly to hard tissue (78%), which were commonest in men, 20 to 29 years of age, and in victims of violence or fall accidents. Severe dental injuries in association with mandibular condyle fractures were more common in accidents due to traffic and miscellaneous causes than in those due to violence. Severe dental injuries were more often encountered when simultaneous mandibular body fracture was present than when it was not and more so in bilateral than unilateral condylar fracture cases. The most important factor correlating with the severity of dental injuries was the presence of bilateral condylar fracture.
Biocompatibility of dentin bonding agents
Authors: Al‐Dawood Abdulrahman , Wennberg Alf
Published: April 2006

Abstract Dentin bonding agents were introduced to enhance the bonding of composite resins to dentin. Many commercial brands of bonding agents are now available for clinical use, and they are getting more and more popular. The third generation of dentin bonding agents seems to be more effective than earlier generations, although more complex to use. Dentin bonding agents have different chemical compositions, different mechanisms of actions, and different clinical application procedures and, conceivably, different biological effects on the pupal tissues are expected. The reported biological effects of dentin bonding agents ranged from none to severe, depending on several factors. Opinsion varied whether the inflammatory reactions associated with some bonding agents were due to the tooth restoration interface, or due to a combination of both factors.
Endodontic status of mandibular premolars and molars in an adult Swedish population. A longitudinal study 1974–1985
Authors: Petersson Kerstin
Published: April 2006

Abstract The purpose of the investigation was to study the incidence of end endodontic treatment and the progression of periapical disease in an adult Swedish population. A random sample was selected in 1974 and offered a clinical and radiographic examination. In 1985, 345 of the original 1302 persons received a follow‐up examination. The present study was based on information obtained from radiographs of the mandibular premolar and molar regions at the two examinations. The highest increase in people with endodontically treated teeth from 1974 to 1985 and the highest increase in people with periapical lesions were found in the youngest age‐group, horn between 1945 and 1954. New endodontic treatment, received between 1974 and 1985, was mostly found among those who already had endodontically treated teeth in 1974. New periapical lesions also appeared more often in persons with endodontic disorders in 1974.
Action of adrenaline on the effect of dental local anaesthetic Solutions
Authors: Pitt Ford T. R. , Seare M. A. , McDonald F.
Published: April 2006

Abstract This study investigated the effects of dental local anaesthetic solutions containing either 2% plain lignocaine or 2% lignocaine with 1:80,000 adrenaline. The duration of anaesthesia and the occurrence of a reduction in blood flow together with its duration were examined in the dental pulps of maxillary central incisor teeth in 10 human subjects. The local anaesthetic solution was injected into the soft tissues adjacent to the apex of the sound maxillary incisor tooth. The blood flow in the dental pulp was assessed by a laser Doppler flowmeter, and the effectiveness of pulpal anaesthesia was determined by an electric pulp tester, both at timed intervals. The injection of 1–2 ml of 2% plain lignocaine had no significant effect on blood flow in the pulp of the incisor tooth in eight of 10 subjects. In the other two, there was a small but significant increase. The duration of pulpal anaesthesia was 25.1 min (SD 6.23). Following injection of 1 ml of 2% lignocaine with 1:80,000 adrenaline, there was a significant reduction (31%) of pulpal blood flow in every subject (p<0.05). The duration of reduced blood flow was 68.5 min (SD 9.73). The duration of pulpal anaesthesia was 100 min (SD 15.09), four times the duration of anaesthesia induced by plain lignocaine. The anaesthetic solution with vasoconstrictor produced far longer anaesthesia more consistently at a lower dose than the plain solution.
Orthodontic closure and transplantation in the treatment of missing anterior teeth. An overview
Authors: Stenvik Arild , Zachrisson Bjørn U.
Published: April 2006

Abstract Orthodontic closure and autotransplantation of teeth are valid treatment alternatives for young individuals with missing anterior teeth. These alternatives have, however, different indications and the choice should be based upon a comprehensive evaluation and diagnosis of the individual. Problems and limitations should be emphasized before treatment in order for the patient to have realistic expectations. The treatment plan will ultimately result from an evaluation of short‐ and long‐term biologic and esthetic considerations. Indications, treatment principles and key factors in the treatment procedure are outlined in this overview. If transplantation is to be part of the treatment plan, the donor tooth which has the best prognosis should be selected.
Traumatic injuries to permanent incisors
Authors: Zerman Nicoletta , Cavalleri Giacomo
Published: April 2006

Abstract The prevalence of traumatic injuries to permanent incisors and their distribution according to type and some clinical factors, were analysed in a total population of 2798 patients, aged 6–21 years, examined over a 5‐year period in the Dental Clinic of the University of Verona, Italy. The material consisted of case histories and radiograms taken during the examination of injured teeth. The number of injured patients was 178 (131 males and 47 females), the number of injured incisors was 326. The prevalence of injuries was 7.3%. A very large number of dental injuries occured to children aged between 6 and 13 years. The ratio of boys to girls was 2.7:1. Most frequent causes of injuries were falls and traffic accidents. Most injuries involved two teeth. About 80% of the teeth were maxillary central incisors. The most common type of injury was non complicated crown fracture. In 87 cases (48%) there was an associated injury to soft tissue. Alveolar fractures occurred in 22 cases (12%). Traumas involving periodontal ligament constituted nearly 40% of the total. This study noted the following points: 1) preventive education programs should be instituted in the region, directed at parents and school teachers, to inform them about the problems of dental trauma and to obtain cooperative attitude to treatment and good motivation in controls; 2) the necessity to unify the diagnostic and therapeutic protocol to provide reliable information in clinical investigations, to permit valid comparison with other studies and to improve the long‐term prognosis of many cases.
Effect of root canal status on periodontal healing after surgical injury in dogs
Authors: Holland R. , Filho J. A. O. , Bernabé P. F. E. , Nery M. J. , de Souza V. , Berbert A.
Published: April 2006

Abstract This study was carried out to observe if the status of the root canal might influence the healing process of surgically prepared experimental periodontal lesions. Forty tooth roots from four dogs were divided into four different groups: a) root canals with vital pulps, b) root canals open to the oral environment, c) root canals infected and filled with zinc oxide eugenol cement, and d) root canals infected and filled with calcium hydroxide. By means of a surgical intervention, a cavity was prepared in the medium portion of the roots. Six months later, the specimens were removed and prepared for histological analysis. The results, which were submitted to statistical analysis, showed that the status of the root canals influenced the healing process of the experimental periodontal lesions. In the groups where the root canals were filled, calcium hydroxide gave the best results. In the group with root canals left open to the oral environment, resorption of the dentin of the experimental cavities, was the most obvious observation. However, it did not prevent the repair process, only slowed it down.
Treatment of intruded permanent incisors: a multidisciplinary approach
Authors: Mamber Evelyn K.
Published: April 2006

Abstract The case presented is a report of a healthy 11‐ year‐old boy, who fell down and traumatized his four maxillary incisors. Both central incisors were deeply intruded with concomitant uncomplicated crown fractures, and both lateral incisors suffered concussion. The intruded teeth were repositioned using a removable orthodontic appliance and were endodontically treated 3 weeks after trauma. Tooth 11 became ankylosed 3 months post trauma, and tooth 21 was extruded to its original position after 5 months. Five months post‐trauma, teeth 12 and 22 underwent necrosis and were endodontically treated. In addition, tooth 22 presented an external inflammatory root re‐sorption that was arrested by calcium hydroxide paste after 3 months. A crown‐lengthening procedure was performed on tooth 11 10 months post‐trauma, exposing the clinical crown to a better condition for restoration. All 4 incisors were restored with a composite material, and the incisal edges of the central incisors were shaped at the same level. Two months after the crown lengthening procedure, spontaneous eruption occurred on tooth 11, that had been ankylosed. The restored incisal edge of tooth 11 was reduced to the same level of tooth 21. The patient is under periodical examination till a definitive orthodontic treatment can be performed.
Testing of sealing ability of endodontic filling materials
Authors: AI‐Ghamdi A. , Wennberg A.
Published: April 2006

Abstract Incomplete obturation of the root canal system is the major cause of endodontic failure. Endodontic filling materials with ability to seal the root canal are, therefore, essential for successful endodontic therapy. However, assessment of scaling ability is not included in the requirements specified in the current international standard covering root canal sealers. A number of different in in vitro methods have been used to evaluate the sealing quality of endodontic filling materials. The tests have usually been leakage tests, i.e. based on assessment of penetration of a tracer along the obturated root canal. Leakage tests have poor reproducibility and are, therefore, not suited for standardized lest programs. By selecting the properties necessary for sealing ability and testing them separately, it might be possible to find a number of tests, which individually are suitable for a standardized test program, and which combined will give information on the sealing ability of the test material.
Effects of cooling and heating of the tooth on pulpal blood flow in man
Authors: Andersen E. , Aars H. , Brodin P.
Published: April 2006

Abstract Laser Doppler flowmetry (LDF) was used to study the changes in pulpal blood flow (PBF) evoked by application of cold or heat to the palatinal surfaces of teeth 11 or 21 in nine young subjects. Switching from a thermode temperature of 33° to 5° G on average induced a slow decrease of PBF to about 80% of control, and also warming to 39°C evoked a small reduction in most subjects. Inter individual differences were large, however, and both cooling and warming sometimes triggered a rise in PBF. In contrast, skin blood flow, as recorded with LDF in the forearm, invariably rose during warming and fell during local cooling. The results suggested a more complex interaction between local and nervously mediated effects of moderate changes in temperature in the tooth pulp than skin, and that the previous held view of cold and heat decreasing and increasing PBF, respectively, is wrong.
An in vitro investigation into the cutting ability of ultrasonic K files
Authors: Lumley P. J. , Walmsley A. D. , Thomas A.
Published: April 2006

Abstract Endosonic files vary in their oscillation when operated in air with the greatest displacement at the unconstrained tip. It was the aim of this study to investigate how files of different lengths and sizes varied in their ability to cut dentine. Single rooted teeth were sectioned to produce 1 mm dentine discs. These were positioned on a plastic block connected to a load transducer. Endosonic K‐files (#15 to 25) were used to cut the disc for 10 s using operator assisted movement. The files contacted the disc at the following points along their length; apical (3 mm from tip), middle 1.8 mm from tip) and coronal (13 mm from tip) under applied loads of 30 and 50 g. The depth of cut produced by each file was measured using light microscopy. The #15 and #25 were similar in their pattern of dentine removal. The #20 file produced a large variation in its cutting ability and was also susceptible to fracture. The lip of the files was prone to constraint at higher loading with the thicker pan of the file producing more cutting. It was concluded that the pattern of dentine removal of endosonic files was affected by the amount of load applied. The displacement amplitudes of endosonic files in air would not appear to be a good indicator of file cutting ability.
Accidental damage to incisors amongst Irish adults
Authors: Holland T. J. , O'Mullane D. M. , Whelton H. P.
Published: April 2006

Abstract Evidence of accidental damage to permanent incisor teeth was recorded as part of a national survey of adult dental health in Ireland. A total of 746 adults aged between 16 and 34 years were examined. The prevalence of injury was considerably higher in males and the majority of subjects in both sexes had just one tooth affected. There was a continuing increase in prevalence with age which appeared to level out after the age of 24. A high level of untreated injuries was noted in both age groups; of those injuries which were treated, composite restorations were more common in the younger age groups while extraction and replacement by a denture was more common in older subjects.
Effectiveness of nickel‐titanium files for preparing curved root canals
Authors: Zmener O. , Balbachan L.
Published: April 2006

Abstract In this study, the effect of 2 different endodontic files on the final shape of curved root canals of extracted single rooted teeth were examined in the scanning electron microscope. The instruments tested were a newly designed nickel‐titanium endodontic file and a conventional K‐type file. The files were used with in and out linear movements with a circumferential motion starting with a size 15 file. Final preparation of the apical thirds of the canals was performed with a size 35 file. Shaping effectiveness of the tested instruments was evaluated in terms of respect for conservation of the apical constriction and the presence or absence of ledging. Our observations revealed that more centered and tapered preparations were obtained with the use of the nickel‐titanium files than with the conventional K‐type files.
An in vitro investigation into the shear bond strengths of two dentine‐bonding agents used in the reattachment of incisal edge fragments
Authors: Badami A. A. , Dunne S. M. , Scheer B.
Published: April 2006

Abstract This in vitro study investigated the shear bond strengths of sectioned bovine incisal edge fragments reattached using Gluma 2000 and Scotchbond 2. Teeth were sectioned 3 mm from the incisal edge using an Acutome with a 0.5 mm diamond wheel running at 90° to the mesial or distal surface of the tooth. Twenty four incisal fragments were rebonded with each of the dentine bonding agents; a further 24 intact incisors were used as a control group. The control group required a mean fracture force of 940(±144) N which was significantly greater (p < 0.01) than that required to fracture fragments rebonded using GLUMA 2000 (609±116) N and Scotchbond 2 (393±97) N. The mean force required to fracture incisal fragments rebonded with GLUMA 2000 was significantly greater (p < 0.01) than that required to fracture incisal fragments rebonded with Scotchbond 2.
Bacteremia in conjunction with endodontic therapy
Authors: Debelian G. J. , Olsen I. , Tronstad L.
Published: April 2006

Abstract This study characterizes oral microorganisms believed to have spread from the root canal into the blood stream during and after endodontic therapy of teeth with Asymptomatic apical periodontitis. Microbiological samples were taken under aseptic conditions from the root canal of 26 single‐rooted teeth in 26 patients. In the endodontic treatment of 13 of the patients (Group 1), the first 3 reamers, sizes 15, 20 and 25, were used to a level 2 mm beyond the apical foramen. In the other 13 patients (Group 2), the instrumentation ended inside the root canal 1 mm short of the apical foramen. Blood samples were taken from the patients during the instrumentation and 10 min after the treatment was completed. Anaerobic microorganisms were isolated from all root canals. In 7 patients of Group 1, Propionibacterium acnes, Peptostreptococcus prevotii, Fusobacterium nucleatum, Prevotella intermedia and Saccharomyces cerevisiae were recovered from the blood. In 4 patients of Group 2, P. intermedia, Actinomyces israelii, Streptococcus intermedius and Streptococcus sanguis were isolated from the blood. Biochemical tests and antibiograms revealed that the isolates from the root canal and blood had identical profiles within the patients, strongly suggesting that the microorganisms isolated from the blood had the root canal as their source.
Maxillary permanent central incisor with abnormal crown size and dens invaginatus: case report
Authors: Duckmanton P. M.
Published: April 2006

Abstract An otherwise healthy young Caucasian Australian was referred because of the unusual radiographic appearance of a maxillary permanent incisor. The tooth was found to have an enlarged crown with palatal cusp and dens invaginatus. Over five years' follow‐up the tooth showed no signs of pulp necrosis. The major problem was the correction of the patient's esthetics as he approached adulthood.
Computerized reconstruction of TEM examined pulpal blood vessels and nerves
Authors: Lyroudia K. , Palakidis K. , Manthos A. , Nikolaidis N. , Pitas I. , Foroglou C.
Published: April 2006

Abstract Five healthy premolars were used for transmission electron microscopy examination and three‐dimensional (3D) reconstruction of pulpal blood vessels and their surrounding nerves. Serial Epon thin sections were taken from specimens. After a series of preprocessing steps that included digitization, contrast enhancement, slice alignment, segmentation and interpolation, three dimensional surface representation was performed using the triangulation method. The findings showed that vessels were usually accompanied by a number of myelinated and unmyelinated nerves. The nerves shared a more or less common course with the vessels. Small arteries presented greater number of nerves in their vicinity, compared to small veins. In the sections examined, no direct contact between the nerve trunks and the wall of the vessels was found; the closest distance measured was approximately 67 μm. The common course of vessels and nerves suggested autonomic innervation on part of the myelinated axons.
Endodontic management of mandibular lateral incisor fused with supernumerary tooth
Authors: Peyrano A. , Zmener O.
Published: April 2006

Abstract In this article we report a case of a mandibular lateral incisor in which 3 separate root canals were located. Clinical and radiographic examinations suggested that fusion had occurred between the mandibular incisor and a supernumerary tooth. The endodontic management of the tooth is described, and repair of an apical periodontitis had occurred after 9 months.
Importance of anatomic variables in endodontic treatment outcomes: case report
Authors: Ida R. D. , Gutmann J. L.
Published: April 2006

Abstract Surgical endodontic treatment was performed after a large periradicular lesion failed to resolve following nonsurgical intervention. The subsequent periradicular surgery resulted in healing with scar formation. Assessment of the resected root apex revealed a complex anatomy. The ramifications of these anatomical findings and the periradicular tissue response in healing are discussed relative to prognosis and ultimate treatment outcomes.
Urinary catecholamine levels in children with and without a history of dentofacial injuries
Authors: Vanderas A. P. , Papagiannoulis L.
Published: April 2006

Abstract This study was conducted to investigate the existence of any differences in the urinary cathecholamine levels in children with and without a history of dentofacial injuries. Three hundred fourteen children, boys and girls, aged 6 to 8 years were included in this study. A questionnaire was distributed to the parents to collect information about the child's history of dentofacial injuries. A 24‐h urine sample was collected for each subject and a representative sample (25 ml) was analyzed by the HPLC technique to assay the catecholamine content. Of the examined children 68 (43 boys and 25 girls) had a history of dentofacial injury and constituted the experimental group. A control group of 68 children (43 boys and 25 girls) without a history of dentofacial injury w as matched by age and sex. The Student t‐test was used to identify any differences in urinary catecholamine levels between the two groups. The 95% probability was used. The results showed statistically significant differences in the mean values of epinephrine, while the differences in norepinephrine and dopamine were not significant. This study suggested that children with emotionally stressful states run a greater risk of having dentofacial injuries.
Effect of carbamide peroxide and hydrogen peroxide on the surface morphology and zinc oxide levels of IBM® fillings
Authors: Rostein I. , Cohenca N. , Mor C. , Moshonov J. , Stabholz A.
Published: April 2006

Abstract – The effect of 10% carbamide peroxide or 10% hydrogen peroxide on the surface morphology and zinc oxide levels of IRM fillings was tested. Ninety IRM samples were treated with either 10% carbamide peroxide, 10% hydrogen peroxide or phosphate buffer which served as control. Treatment consisted of placing the samples in a dry incubator at 37°C for 1, 3 or 7 days. At each time point, the samples were removed from the test solutions, dried and prepared for surface scanning electron microscopy and energy dispersive spectrometric analysis. After 3 days, 10% carbamide peroxide significantly reduced the zinc oxide levels as compared to the 10% hydrogen peroxide group (p < 0.01) and the controls (p < 0.01). 10% hydrogen peroxide reduced the zinc oxide levels similarily to the control. No significant changes in the zinc oxide levels were found between 3 and 7 days in any of the groups tested. Microscopic examination of the carbamide peroxide group revealed granular surface with well defined crystalline areas. In the hydrogen peroxide group, numerous cracks with multiple sun burst‐like areas were found. At the macroscopic level, the samples of this group appeared cracked and more swollen, as compared to controls and samples treated with carbamide peroxide. In conclusion, both 10% carbamide peroxide and 10% hydrogen peroxide altered the surface morphology and the zinc oxide levels of IRM fillings, but their modes of action differed.
Microbial flora of sinus tracts and root canals of non‐vital teeth
Authors: Weiger R. , Manncke B. , Werner H. , Löst C.
Published: April 2006

Abstract The occurrence of bacteria in 12 endodontically induced periodontal lesions associated with sinus tracts was examined. The microbial flora encountered in the sinus tract was compared with that of the root canal of the involved teeth which had not experienced any prior endodontic therapy. All microbiological samples taken from the sinus tract and from the root canal system contained bacteria. Seventy‐one strains were detected in the extraradicular lesions. Of the anaerobic species, Fusobacterium nucleatum (7 strains), Prevotella intermedia (4 strains) and P. oralis (4 strains) were most frequently found. In the group of the facultative anaerobes Streptococcus spp. were predominant. Ninety‐four strains were isolated from the root canal system of the 12 teeth. P. intermedia (6 strains), P. buccae (5 strains), F. nucleatum (5 strains) and Lactobacillus plantarum (5 strains) were most common. In 9 cases, species present in the root canal could be revealed in the extraradicular lesions. It was concluded that a variety of microorganisms were capable of colonizing endodontically induced, extraradicular lesions clinically characterized by sinus tracts.
Risk of endodontic treatment after insertion of conical crown retained dentures: a longitudinal study
Authors: Walther W.
Published: April 2006

Abstract A longitudinal study was performed to assess the frequency of endodontic treatment after incorporation of conical crown retained dentures. The study population consisted of all patients being treated with conical crowns at the Academy of Advanced Dental Studies Karlsruhe during the years 1983–1989. The material comprised 655 patients with 1983 vital abutment teeth. The cases were included in a computer based documentation system for recording clinical relevant events. Event analysis by use of the Kaplan‐Meier method revealed, that the probability of not being involved in endodontic treatment decreased to 0.67 within an observation period of five years. Patients in the oldest age‐group (above 65 years) showed a significantly higher risk of endodontic complications than younger patients. Molars exhibited a less pronounced risk than premolars and anterior teeth. The results confirmed the necessity of regular follow‐up examinations after prosthetic procedures.
Traumatic dental injuries at the Accident and Emergency Department of Singapore General Hospital
Authors: Sae‐Lim Varawan , Hon Tan Hee , Wing Yuen Kwong
Published: April 2006

Abstract The purpose of this retrospective study was to determine the occurrence and the type of after office‐hours traumatic dental injuries managed by the Dental Unit of the Accident and Emergency Department at the Singapore General Hospital. During a 2‐year period (from August 1990 to July 1992), 461 trauma patients (314 males, 147 females) sustained injuries to 968 teeth. The distribution in different races of Chinese: Malay: Indian: others was 7.3: 1.3: 0.9: 0.5. The predominant age groups were 2–3 years, 3–4 years and 17–18 years; 71.3% of the teeth sustained luxation type injuries, the remaining 28.7% had fractures, 45.3% of the cohort had concomitant soft tissues injuries, while 13.7% had associated facial bone fractures. Teenager traumas were more common during school vacations. It is concluded that thorough standardized documentation is imperative to obtain baseline information on dental trauma. This could facilitate future preventive measures, education and research.
Transient apical breakdown following subluxation injury: a case report
Authors: Boyd K. S.
Published: April 2006

Abstract Transient apical breakdown has been reported to occur in cases in which a periapical radiolucency develops and resolves without treatment following luxation injury. Diagnostic errors are inevitable if periapical breakdown is used as the sole criterion or as an overriding criterion in the decision to initiate root canal treatment. A clinical case report is presented in which transient apical breakdown occurred after a subluxation injury. The threshold to sensitivity tests increased yet sensitivity remained positive with the appearance of the periapical radiolucency. The decision was made not to initiate root canal treatment in spite of the radiographic appearance periapically. At the 10‐month recall the tooth remained responsive to sensitivity tests and the apical radiolucency had disappeared.
Surface morphology changes in human enamel, dentin and cementum following bleaching: a scanning electron microscopy study
Authors: Zalkind M. , Arwaz J. R. , Goldman A. , Rotstein I.
Published: April 2006

Abstract Extracted human premolars were cut, cleaned and divided into 6 experimental groups. Each group was treated with one of the following bleaching materials: 30% hydrogen peroxide, 10% carbamide peroxide, sodium perborate, Nu‐Smile, Opalescence and DentlBright. Morphological changes in tooth surface occurred following treatment with most bleaching agents. Hydrogen peroxide and DentlBright were associated with surface changes in all dental tissues. Hydrogen peroxide, DentlBright, Nu‐Smile and Opalesceilce were mainly associated will) surface changes in the cementum, which exhibited more changes than the other tissues.
Effects of Prilocaine local anaesthetic solutions on pulpal blood flow in maxillary canines
Authors: Chng H. S. , Pitt Ford T. R. , McDonald F.
Published: April 2006

Abstract The effects of prilocaine local anaesthetic solutions on pulpal blood flow (PBF) in maxillary canines were investigated in nine adult subjects. Buccal infiltration of 2 ml of the following solutions were carried out: 3% prilocaine; 3% prilocaine with 0.03 IU/ml felyprcssin; and 3% prilocaine with 1:100,000 adrenaline. Blood (low in the anaesthetized tooth was monitored by a laser Doppler flowmeter and data stored in a computer. An electric pulp tester was used to assess pulpal anaesthesia. The duration of anaesthesia was recorded. After administration of plain prilocaine, PBF changed little throughout the experiment in all nine subjects. When prilocaine with felypressin was injected, PBF fluctuated greatly, but there was no sustained increase or decrease. In comparison, prilocaine with adrenaline caused a significant decline in PBF in every subject (p<0.05), but then gradually started lo return to the pre‐injection level; there was no such change in PBF of the contralateral tooth. Injection of 3% plain prilocaine achieved a short duration of pulpal anaesthesia (median 7 min) in only three subjects. When prilocaine with felypressin was injected, eight out of nine subjects experienced pulpal anaesthesia (median duration 10.5 min). Injection of prilocaine with adrenaline caused pulpal anaesthesia in six of nine subjects (median duration 10.5 min). The use of vasoconstrictors with prilocaine anaesthetics had less pronounced effects on blood How and shorter periods of anaesthesia than those reported previously for lignocaine with adrenaline.
Effect of retrograde cavity preparations on root apexes
Authors: Frank R. J. , Antrim D. D. , Bakland L. K.
Published: April 2006

Abstract Ultrasonic cavity preparations in endodontic surgery has become a popular procedure with several advantages noted: Smaller cavities, deeper and cleaner preparations, less removal of surrounding bone needed for instrumentation and less removal of root apex dentin. Concern has been raised that lines of infraction have appeared in some instances when the ultrasonic instruments have been used. We wished to examine the result of cavity preparations in root apexes using five different methods: high and slow speed handpieces, sonic instruments, and ultrasonic instruments at two power settings, medium and high levels, respectively. The results showed that all the methods produced some infractions; the high power ultrasonics produced the most infractions while the fewest numbers were associated with the slow speed handpiece and ultrasonic instruments at the medium power setting.
Measurement of tooth mobility in children using the periotest
Authors: Mackie I. , Ghrebi S. , Worthington H.
Published: April 2006

Abstract This study investigated the use of the periotest for measuring tooth mobility of upper permanent incisor teeth in children. A total of 160 children, with equal numbers of boys and girls aged between 9 and 16 years had two periotest readings made on their Four upper incisor teeth. In all 1,280 measurements were collected and analysed. The results showed that the‐ second periotest readings were statistically significantly higher than the first. Periotest readings were lower for girls than boys of the1 same ages. The periotest may have a place as a diagnostic tool in paediatric dentistry and dental traumatology, however, further re‐search is necessary before die periotest can be used to assist in (he diagnosis and assessment of healing of traumatised teeth.
Torsional and bending properties of stainless steel and nickel titanium Canal Master U and Flexogate instruments
Authors: Canalda‐Sahli C. , Brau‐Aguadé E. , Berástegui‐Jimeno E.
Published: April 2006

Abstract The purpose of this Study was to assess and to compare the torsional and bending properties of the Canal Master U (CMU) and Flexogate instruments made of stainless steel and nickel titanium. The bending moment, the torsional moment and angular deflection were measured according to ANSI/ADA specification number 28 and ISO reference number 3630. Ten instruments of each size, sizes 25 to 40 were used for each test. Nickel titanium instruments were significantly more flexible than stainless steel files. With regard to the torsional moment, values obtained were below the standards in all sizes except stainless steel CMU sizes 25, 35 and 10, and nickel titanium CMU size 25. Nickel titanium instrument also showed the highest angular deflection values. There were statistically significant differences between nickel titanium files and stainless steel Flexogates and between stainless steel Flexogates and stainless steel CMU. Based on these findings, the use of nickel titanium CMU and Flexogates is encouraged. Given the perceived advantages of both CMU and Flexogate instruments over conventional files for canal preparation, it would appear desirable to have the torque resistance of these instruments improved.
Periapical actinomycosis: report of a case and review of the literature
Authors: Sakellariou P. L.
Published: April 2006

Abstract This case of periapical actinomycosis presented the clinical picture of chronic periapical inflammation. The diagnosis was based on the histological examination of the periapical lesions suggesting the necessity for routine histological examination. Although root canals provide a primary port of entry the Actinomyces organisms into the periapical tissue, periapical actinomycosis, is considered extremely rare. This may be due to the omission of routine histological examination of periapical lesions and the clinical behavior of the disease. The large number of cases reported during the last decade indicates that periapical actinomycosis is more frequent than what it is believed and this is important in the daily dental practice.
Root end filling materials: a review
Authors: Torabinejad M. , Ford T.R. Pitt
Published: April 2006

Abstract When non‐surgical attempts prove unsuccessful or are contraindicated, surgical endodontic therapy is needed to save the tooth. The procedure usually consists of exposure of the involved area, root end resection, root end preparation and insertion of a root end filling material. Numerous materials have been suggested as root end filling materials. This article is a review of the literature on the suitability of various root end filling materials based on their leakage assessment, marginal adaptation, cytotoxicity, and usage test in experimental animals and humans.
Factors affecting the wear of sonic files
Authors: Lumley P. J.
Published: April 2006

Abstract The aim of this study was to investigate (actors affecting; the wear and culling ability of sonic files. A model system was used and the following variables evaluated, file type; Heliosonic, Rispisonic or Shaper, load; 25. 50 or 100 grams and length of time in use; new, 30 or 60 seconds. A 33 full factorial analysis with two replications into the effect of the above variables on the culling ability of the Heliosonic, Rispisonic and Shaper files powered by the MM 1500 sonic instrument was performed. A new file size 25 (Heliosonic and Shaper) or No 3 (Rispisonic) was used for each cut together with water irrigation and the substrate used was 1 mm thick sections of bovine bone. All variables bad a significant effect on culling (ANOVA, p<0.001). However examination of the F values showed that the most significant variable was load, followed by file type, and time. The most significant interaction was between file type and load followed by lime and file type. The interaction between time and load was not significant (p>0.05). The Rispisonic file was most susceptible to wear during use especially at higher loads and the Heliosonic file cut least. It is suggested that the Shaper file is the better design of the three with respect to cutting ability and wear with use.