A combined frontal and maxillary sinus approach for repulsion of the third maxillary molar in a horse.
The 3rd maxillary molar is a difficult tooth to remove by extraction or repulsion. A combined frontal and maxillary approach provides good exposure for repulsion of this tooth, debridement of the sinuses, and placement of an alveolar seal. The improved exposure should minimize operative difficulties and postoperative complications. (+info)
Dental abnormalities in rats after a single large dose of cyclophosphamide.
Delayed drug-related mortality in rats treated with a single high dose (75 mg/kg) of cyclophosphamide complicated experiments using this drug treatment. We observed that this delayed mortality was due to dental abnormalities including broken teeth, absent teeth, extra long teeth, and/or supernumerary teeth. These dental abnormalities developed about 140 days after treatment and, if left untreated, interfered with eating. Eventually, the untreated rats starved. Clipping their long teeth and feeding the rats powdered chow eliminated the deaths. Researchers should be aware that high doses of cyclophosphamide may result in dental abnormalities several months after the treatment. (+info)
Good occlusal practice in children's dentistry.
The difference between paediatric dentistry and most other branches of dentistry is that in the child the occlusion is changing. Consequently 'Good Occlusal Practice' in children is a matter of making the right clinical decisions for the future occlusion. The clinician needs to be able to predict the influence that different treatment options will have on the occlusion when the child's development is complete. (+info)
Effect of tubule orientation and dentin location on the microtensile strength of bovine root dentin.
To investigate the mechanical properties of root dentin and to further clarify the cause of vertical root fracture (VRF), this study evaluated the effect of tubule orientation (parallel, perpendicular and oblique to the cross-section of dumbbell specimens in microtensile tests) and dentin location (cervical, middle, and apical location of the root) on the microtensile strength of bovine root dentin. Each specimen was stressed in tension at a crosshead speed of 1.0 mm/min. The results of the microtensile strength measurements were statistically analyzed with one-way ANOVA and the Fisher PLSD. The oblique group (95.18+/-23.80 MPa) was significantly (p<0.01) higher than the parallel group (38.93+/-5.28 MPa) or the perpendicular group (32.64+/-4.69 MPa). There were no significant differences among the different dentin locations within the parallel group (p>0.05). It was clarified that the VRF occurs frequently in practical situations due to the tubule orientation of root dentin. (+info)
A modified impression technique for accurate registration of peri-implant soft tissues.
Replacement of single missing teeth with an implant-supported restoration is recognized as a highly successful treatment. An impression technique for peri-implant soft-tissue replication in an anterior zone is described. The technique involves use of an interim restoration as an abutment for the final impression. This allows accurate duplication of the soft tissues and fabrication of a final restoration with the correct emergence profile. (+info)
Unusual migratory foreign body in the neck.
Reports of ingested foreign bodies penetrating the pharynx and migrating through the neck are rare, and mostly involved fish bones. We describe a 44-year-old man who was involved in a motor vehicle accident and accidentally swallowed his tooth. The swallowed tooth penetrated the pharynx and became lodged adjacent to his right thyroid gland. It was successfully removed via neck exploration and the patient recovered well. (+info)
Effect of the ferrule on fracture resistance of teeth restored with prefabricated posts and composite cores.
BACKGROUND: The ferrule effect in root treated teeth requiring cast posts and cores has been shown to greatly improve fracture resistance. Studies have also shown that in the case of a cast post and core, the longer the ferrule, the greater the fracture resistance. However few studies have considered the effect of different ferrule designs on prefabricated post and composite core systems. AIM: This study investigated the effect of different ferrule designs on the fracture resistance of teeth incorporating prefabricated posts and composite cores. It also assessed the necessity of a post in the restoration of endodontically treated teeth. METHODOLOGY: Sixty-two extracted maxillary incisors (centrals and laterals) and canines were randomly assigned into three groups and restored. Two groups had a prefabricated post and composite core with varying ferrule designs. A third group had a core with composite packed into the root canal but no post. An Instron universal testing machine was used to apply compressive loads until failure occurred. RESULTS: There was no significant difference amongst the three groups as regards fracture resistance. The two groups with prefabricated posts and composite core required a mean force of 931N, std +/-283 and 931N, Std +/-242 to fracture. The third with no post group required a mean force of 1036N, std +/-269 to fracture. CONCLUSION: In the restoration of an anterior endodontically treated tooth with a prefabricated post and composite core and where there is at least 2 mm or more of remaining coronal dentine, a ferrule may not be necessary. (+info)
Orthodontic extrusion: periodontal considerations and applications.
Human teeth erupt naturally to compensate for tooth wear and tear. When a subgingival lesion such as crown fracture occurs, the general practitioner must consider orthodontic extrusion of the tooth to allow for prosthetic rehabilitation. However, because this therapeutic approach is not appropriate in all cases, each tooth must be carefully analyzed before treatment. The amount of force applied depends on the desired effect. Orthodontic extrusion can also be used to augment bone and tissue in the course of preparing an implant site. In most cases, endodontic treatment must be completed first, with close attention being paid to the contour of the final restoration. The benefits of extrusion are clear, but patients must nonetheless be informed of the disadvantages. (+info)