Guidelines for the evaluation and management of traumatic dental injuries.
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Child↗
Biomedical subjects
T R Ford
Publications and source records attributed to T R Ford.
Guidelines for the evaluation and management of traumatic dental injuries.
Explore the source record for details and available documents.
Alveolar Process↗
The efficacy of gutta-percha removal using ProFiles.
AIM: The purpose of this study was to compare the efficacy in vitro of gutta-percha removal from obturated root canals using ProFiles. METHODOLOGY: Forty-eight human root canals with curvatures ranging between 25 and 45 degrees were instrumented by a standardized method to an apical ISO size 30 and 0.04 taper. They were obturated with vertically condensed gutta-percha. Retreatment was performed with the following techniques: K-Flexofiles with chloroform; Hedstrom files with chloroform; ProFiles 0.04 taper with chloroform; ProFiles 0.04 taper alone. The time for each method was measured. A microfocal macroradiographic technique was used to evaluate the amount of debris remaining within the root canals after the retreatment procedure. Roots were divided into apical, middle and coronal parts and scored on a scale of 0 (no debris) to 3 (> 50% of walls covered with debris) by trained observers on two separate occasions. RESULTS: The scores for debris remaining within root canals for K-Flexofiles with chloroform and ProFiles with chloroform were the lowest and not significantly different at all three levels of the roots examined (P > 0.05), and Hedstrom files with chloroform and ProFiles with chloroform were not significantly different in the apical part. In general, coronal parts were cleaner than apical parts. The difference in scores at the three levels between ProFiles with chloroform and ProFiles alone were each significant (P < 0.01). Instrumentation using ProFiles with chloroform (mean 6.42 min) was significantly faster than using hand files (mean 11.67 min) (P < 0.01). CONCLUSION: The results indicated that ProFiles or hand files with chloroform produced similarly clean canals, but that ProFiles were faster.
Chloroform↗
Prophylactic treatment of dens evaginatus using mineral trioxide aggregate.
Two case reports with dens evaginatus are presented. Each patient had one tooth affected. There was a prominent tubercle on the occlusal surface of the mandibular second premolar. Under local anesthesia and rubber dam isolation a partial pulpotomy was conducted and mineral trioxide aggregate was placed. After 6 months the teeth were removed as part of planned orthodontic treatment. Histological examination of these teeth showed an apparent continuous dentin bridge formation in both teeth, and the pulps were free of inflammation. These cases show that mineral trioxide aggregate can be used as an alternative to existing materials in the proplylactic treatment of dens evaginatus.
Aluminum Compounds↗
Dentine chips produced by nickel-titanium rotary instruments.
This study aimed to compare the cross-sectional shape of two nickel-titanium rotary instruments, namely ProFile and Quantec files, both ISO 25, 0.06 taper, and sought to relate this to the chips produced by cutting dentine. A limited comparison was made with stainless steel engine reamers. First, five files of each type were sectioned transversely at 12 mm, 8 mm and 4 mm from the tip and examined by scanning electron microscopy. The cutting angles were assessed by a direct measurement technique which allowed for the inclination of a cutting edge to the root canal. Second, eight samples of cutting debris were collected from instrumentation by each type of nickel-titanium file and four samples from the engine reamers. The major and minor axis, area and roundness of the dentine chips in each sample were measured using computerized particle analysis. The results demonstrated that all files had a negative cutting angle which varied at the different levels (ProFiles range 69.4 degrees to 58.4 degrees and Quantec range 74.8 degrees to 56.8 degrees). The consistency within files of the same type was good as demonstrated by low standard deviations, except for Quantec files at the 4 mm level where higher standard deviations of 4.1 degrees and 5.5 degrees for the two blades were found. The chip analysis showed significant differences between chips produced by ProFile and Quantec files (P < 0.05). The latter were larger and rounder. The chips from the ProFile and the engine reamer chips were similar in dimension (P > 0.05). No simple relationship existed between file geometry and the dentine chips produced during instrumentation.
Dental Alloys↗
A comparison of two nickel-titanium instrumentation techniques in teeth using microcomputed tomography.
AIM: The aim of the study was to compare the shaping of root canals by two nickel-titanium instrumentation techniques using microcomputed tomography (MCT). METHODOLOGY: Ten mandibular first molar teeth (30 canals) that had intact crowns and fully formed roots were scanned using MCT. Fifteen canals were instrumented using NiTiFlex hand files (Maillefer) using balanced force. The remainder were instrumented using prototype ProFile 0.04 Taper instruments (Dentsply) in a crown-down manner to an apical size ISO 25. The teeth were scanned again following instrumentation. The two instrumentation techniques were compared in a total of 27 canals. The area of dentine removed at predetermined levels (2.0, 3.0, 4.5, 6.0, 7.5 mm) from the apex was measured. Transportation and centring were recorded. Images constructed at these levels were compared with video images of equivalent physical sections created after the second scan. The volume of dentine removed in the apical 7.5 mm of the root canals of each tooth was calculated and the different techniques compared. Rendered three-dimensional images were used to assess the preparations qualitatively. The time taken for preparation was recorded. RESULTS: There was no significant difference between hand instrumentation with NitiFlex files and machine instrumentation with prototype ProFile 0.04 Taper instruments for any of the variables tested. CONCLUSIONS: Both techniques produced well centred and tapered preparations.
Dental High-Speed Technique↗
Micro-computed tomography: a new tool for experimental endodontology.
AIM: Micro-computed tomography (MCT) using conebeam geometry is a method of producing true 3D images of the structure of small samples. A prototype MCT unit was adapted for imaging teeth to examine whether it could be used to quantify the instrumentation of root canals. METHODOLOGY: Ten mandibular first molar teeth that had intact crowns and fully formed roots were scanned using MCT at a resolution of 0.081 mm and 3D-rendered images created; root canals were segmented from this. Reproducibility of MCT was verified for root canal shape and size. Access cavities were prepared into the pulp space and root canals enlarged to a continously tapering preparation using a crowndown technique. Each tooth was scanned again to allow comparison of pre- and post-instrumentation images. The roots were then sectioned at five predetermined horizontal levels for video-digitized measurement of dimensions of roots and root canals. The video images had a resolution of 0.025 mm. Video-digitized images of the physical cut surfaces were compared with equivalent MCT reconstructed images. The total area of the root canals (internal) and root (external) at each level were calculated from both MCT reconstructions and video-digitized images, and compared. RESULTS: There was a highly significant correlation between MCT and video images for both external and internal areas (r = 0.94). Rendered 3D images were constructed to show the root canal systems of teeth. The total volumes of the apical 7.5 mm of root canals were calculated from rendered images of nine teeth before and after instrumentation. The mean amount of dentine removed by instrumentation was 3.725 mm3, which was 28% of the original canal volume. CONCLUSIONS: Micro-computed tomography was shown to be accurate for experimental endodontology.
Anatomy, Cross-Sectional↗
Laser light transmission in teeth: a study of the patterns in different species.
AIM: The aim of this study was to investigate the pattern of light transmission through teeth of different species and to examine laser light propagation within enamel from various animal sources. METHODOLOGY: Sectioned teeth from five species--pig, horse, sheep, cat and rat--were evaluated. Samples were illuminated individually by a helium-neon laser light from the buccal surface using a probe 0.5 mm in diameter placed at varying angles between 60 and 120 degrees C. The pattern of light transmission was observed macroscopically. Further evaluation of laser light transmission in enamel was achieved using confocal microscopy. RESULTS: In each species, light was transmitted through the tooth to the pulp, but in the cat and the rat, light was also transmitted to the far side of the tooth. Despite the different patterns of enamel in the species, light was transmitted through enamel to dentine. CONCLUSION: Light from a laser Doppler probe appeared to reach the dental pulp in all the species: however, in the mammals with smaller teeth, light may also have been able to reach the periodontium and thus the reflected signal may not be entirely of pulpal origin.
Animals↗
Tissue reaction to implanted root-end filling materials in the tibia and mandible of guinea pigs.
The purpose of this study was to examine the tissue reaction to implanted mineral trioxide aggregate (MTA), amalgam, Intermediate Restorative Material, and Super-EBA in the tibias and mandibles of guinea pigs. After anesthetizing 20 guinea pigs, raising tissue flaps, and preparing bony cavities, the test materials were placed in Teflon cups and implanted in the tibias and 10 days later in the mandibles. The animals were euthanized 80 days later and the tissues prepared for histological examination. The presence of inflammation, predominant cell type, and thickness of fibrous connective tissue adjacent to each implant were recorded. The tissue reaction to MTA implantation was the most favorable observed at both sites; as in every specimen, it was free of inflammation (p < 0.01). In the tibia, MTA was the material most often observed with direct bone apposition. Based on these results, MTA seems to be a biocompatible material.
Aluminum Compounds↗
Radiopacity of resin-modified glass ionomer liners and bases.
STATEMENT OF PROBLEM: Lining and base materials for restorations have traditionally been autopolymerized and include conventional glass ionomer cements. Light-cured resin-modified glass ionomer cements have recently become available, but a lack of information exists regarding their radiopacity. PURPOSE OF STUDY: In this study the radiopacity of glass ionomer cements was assessed with a standard method that related densitometric measurements to an equivalent thickness of aluminum. MATERIAL AND METHODS: Radiographs were made of specimens with seven materials commonly used as liners and bases: two reinforced zinc oxide-eugenol cements (Kalzinol and Intermediate Restorative Material, De Trey Dentsply), a zinc phosphate cement (SS White, S.S. White Manufacturing), three resin-modified glass ionomer liners (Vitrebond [3M Dental Products], Fuji Lining LC [GC Dental], and Photac-Bond [ESPE Dental Medizin GmbH]), and a conventional glass ionomer liner/base (Ketac-Bond, ESPE Dental-Medizin GmbH), with dentin as a control. The radiopacity of all materials was compared with dentin. RESULTS: Kalzinol had the greatest radiopacity of the materials tested. The glass ionomer cements were substantially less radiopaque than other materials. The conventional glass ionomer cement, Ketac-Bond, was more radiopaque than the three resin-modified glass ionomer cements. Of the three resin-modified glass ionomer materials, Vitrebond was the most radiopaque and Fuji Lining LC was the least radiopaque. CONCLUSION: Future resin-modified glass ionomer materials are recommended to be formulated to increase radiopacity for improved clinical detection.
Absorptiometry, Photon↗
Radiological assessment of the effects of potential root-end filling materials on healing after endodontic surgery.
The effects of three root-end filling materials on healing following endodontic surgery were assessed radiologically and correlated with histological findings reported elsewhere. The materials compared were a light-cured glass ionomer cement (Vitrebond), a reinforced zinc oxide-eugenol cement (Kalzinol) and amalgam. The root canals of 27 two-rooted mandibular premolar teeth of six beagle dogs were inoculated with endodontic pathogenic bacteria to induce periradicular lesions. The roots were apicected and root-end cavities filled with the tested filling materials. The teeth and surrounding jaw were removed after 4 weeks (30 roots) or 8 weeks (24 roots). Radiographs were taken of each jaw section and subjected to image analysis. Healing was evaluated based on measurements of the size of the periradicular radiolucent areas. ANOVA disclosed no statistically significant differences in the size of the periradicular areas either between time periods or between materials. These results did not correlate with the tissue responses in the same material as assessed histologically and previously reported. The use of radiographs alone to assess healing after endodontic surgery in the dog mandible is unsatisfactory, and should not be regarded as a substitute for histological examination for the determination of healing.
Analysis of Variance↗
Tissue response to potential root-end filling materials in infected root canals.
The tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol) were compared with that to amalgam. In 27 premolar teeth of beagle dogs (54 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periapical lesions. On each root, an apicectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 8 weeks (24 roots) and 4 weeks (30 roots); and they were prepared for histological examination. The tissue response to amalgam fillings after 4 and 8 weeks was marked by moderate or severe inflammation on all roots, and extended > 0.5 mm in 10 out of 18 roots. In contrast, after 8 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation while the tissue response to Vitrebond was the best of the three materials, and was also less extensive. After 4 weeks, the overall best tissue response was with Kalzinol, followed closely by Vitrebond. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were statistically significant (P < 0.01). Similarly, the differences between materials for both time periods with no inflammation or inflammation extending < 0.2 mm when compared with that with inflammation extending > 0.2 mm (< or = 0.5 mm or > 0.5 mm) were statistically significant (P < 0.01). Both Vitrebond and Kalzinol have potential as root-end filling materials as the tissue response was considerably more favourable than that to amalgam.
Animals↗
Effect of probe design and bandwidth on laser Doppler readings from vital and root-filled teeth.
Laser Doppler flowmetry has been shown to be useful in assessing blood flow in teeth. This study investigated the effect of probe design and bandwidth on laser Doppler readings from vital and root-filled teeth using an 810 nm light source, and established the sensitivity and specificity of each probe/bandwidth combination. Readings were taken from 20 human subjects with a root-filled tooth and a vital contralateral tooth using each of the probes with 0.125 mm, 0.375 mm and 0.5 mm fibre separations and three bandwidths (3.1 kHz, 14.9 kHz and 20 kHz). Ten pairs of traces from each group were examined by 10 trained observers who indicated whether the traces had come from a vital or root-filled tooth. The sensitivity and specificity of each combination were calculated from the accuracy of their replies. This was repeated for five observers but with additional information from Fourier analysis. Median readings from vital teeth were higher than those from root-filled teeth for all combinations. This difference was only significant at the 95% confidence level for the 0.5 mm probe with the two lower bandwidths. The 0.125 mm fibre separation probe showed good specificity. The other two probes had better sensitivity but poor specificity. The best specificity and sensitivity was shown by the 0.5 mm probe/3.1 kHz bandwidth combination. All sensitivities and specificities increased when additional information from Fourier analysis was available, but the 0.5 mm probe/3.1 kHz combination still had the best sensitivity and specificity.
Blood Flow Velocity↗
Radiopacity of potential root-end filling materials.
OBJECTIVES: In recent years various root-end filling materials have been suggested for clinical use. The purpose of this study was to assess the radiopacity of some potential materials according to ISO specification 6876. STUDY DESIGN: Radiographs were taken of 1-mm thick specimens of eight materials (amalgam, Kalzinol, IRM, Super EBA, Vitrebond, Fuji II LC, Chemfil, gutta-percha); light transmission was assessed densitometrically and related to equivalent thickness of aluminum. RESULTS: Commercial glass ionomer cements (Vitrebond, Fuji II LC, Chemfil) had radiopacities below the international standard for root canal sealers (< 3-mm aluminum); three zinc oxide-eugenol cements (Kalzinol, Super EBA, IRM) had radiopacities equivalent to 5 to 8 mm aluminum; and gutta-percha had a radiopacity equivalent to 6.1-mm aluminum. CONCLUSIONS: We recommend that root-end filling materials should have a radiopacity greater than that for root canal sealers.
Absorptiometry, Photon↗
Orthodontic management of root-filled teeth.
Orthodontists are often concerned about the prognosis of root-filled teeth, particularly when extractions are required for orthodontic treatment. This review provides guidance on assessing the quality of root fillings, as well as the factors which affect the prognosis of root-filled teeth. The implications of previous traumatic injuries and the likelihood of root resorption during orthodontic tooth movement are discussed.
Humans↗
Using mineral trioxide aggregate as a pulp-capping material.
This study examined the dental pulp responses in monkeys to mineral trioxide aggregate, or MTA, and a calcium hydroxide preparation when used as pulp-capping materials. After the pulps of 12 mandibular incisors were exposed with a No. 1 round bur, they were capped with either MTA or the calcium hydroxide preparation. After five months, the authors noted no pulpal inflammation in five of six samples capped with MTA, and all six pulps in this group had a complete dentin bridge. In contrast, all of the pulps capped with the calcium hydroxide preparation showed pulpal inflammation, and bridge formation occurred in only two samples. Based on these results, it appears that MTA has the potential to be used as a pulp-capping material during vital pulp therapy.
Aluminum Compounds↗
Use of mineral trioxide aggregate for repair of furcal perforations.
The histologic response to intentional perforation in the furcations of 28 mandibular premolars in seven dogs was investigated. In half the teeth, the perforations were repaired immediately with either amalgam or mineral trioxide aggregate; in the rest the perforations were left open to salivary contamination before repair. All repaired perforations were left for 4 months before histologic examination of vertical sections through the site. In the immediately repaired group, all the amalgam specimens were associated with inflammation, whereas only one of six with mineral trioxide aggregate was; further, the five noninflamed mineral trioxide aggregate specimens had some cementum over the repair material. In the delayed group, all the amalgam specimens were associated with inflammation; in contrast only four of seven filled with the aggregate were inflamed. On the basis of these results, it appears that mineral trioxide aggregate is a far more suitable material than amalgam for perforation repair, particularly when used immediately after perforation.
Aluminum Compounds↗