Severe Erosive Lesions Research Articles

Questionnaire Survey on the Management of Erosive Tooth Wear.

This questionnaire survey aimed to analyse management strategies for erosive tooth wear and to identify factors influencing dentists' decision-making. A questionnaire presenting clinical cases with erosive tooth wear on anterior and posterior teeth (BEWE scores 1 to 3) was sent electronically to German dentists (n = 13.683). Statistical analysis was performed by Wilcoxon signed-rank tests, Kruskal-Wallis-tests and Fisher's exact tests (p <0.05). Only 455 dentists (3.3%, mean age: 52.3 ± 9.6) participated. Suggested therapeutic measures were statistically significantly different between BEWE 1, 2 and 3 (p <0.001) and between anterior and posterior teeth with BEWE scores 1 or 2 (p ≤0.025). Initial erosive lesions (BEWE 1) were mainly treated by information about the main causes and/or preventive measures (posterior teeth: 75.6%, anterior teeth: 64.4%), only 20.0% and 31.3% considered restorative treatment for posterior and anterior teeth, respectively. For teeth presenting score 2, a very high proportion of dentists considered restorative treatment (posterior teeth: 60.6%) additionally to prevention, especially when anterior teeth (91.0%) were affected. In case of severe erosive lesions (BEWE 3), the vast majority of dentists considered restorative treatment (posterior teeth: 98.3%, anterior teeth: 99.8%). The decision-making was mainly dependent on the lesion depth, size of affected surfaces and the presence of pain. Fluoride agents and agents containing tin chloride or tin fluoride were most frequently recommended as preventive measures. If distinct defects (BEWE 2) were treated restoratively, mainly composite restorations were performed (posterior teeth: 72.0%, anterior teeth: 90.5%). Severe defects (BEWE 3) were mostly restored with ceramic restorations (posterior teeth: 66.1%, anterior teeth: 66.6%). Stepwise management of erosive tooth wear was observed. Dentists' decision-making was related to severity and localisation of erosive tooth wear and to various patient-related factors (e.g. depth of lesion and size of affected surface per tooth).

Modeling of ultrathin occlusal veneers

ObjectiveThe purpose of this investigation was to compare stresses within bonded porcelain and composite resin ultra-thin occlusal veneers to restore advanced erosive lesions. Materials and methodsA sound maxillary molar was digitized with a micro-CT scanner. The 2D image data were converted in a 3D model using an interactive medical image processing software (Mimics). Standard triangle language files (STL files) of enamel and dentin surfaces were then exported to the software 3-matic to execute design and meshing operations. Solid 3-dimensional (3-D) models acquired in a finite element software (Marc/Mentat) were subjected to nonlinear contact analysis to simulate occlusal loading at 200N and 800N. Values of maximum principal stress and ultimate tensile strength were used to calculate the risk of fracture and for validation with existing experimental data. ResultsThere were marked differences in stress distributions both at 200N (maximum peak values of 21.59, 28.63, 31.04MPa) and 800N (96.16, 115.73, 134.90MPa) for all restorative materials (MZ100, Empress CAD and e.max CAD, respectively). High tensile stresses (measured in the central groove) were found at 800N with the ceramic occlusal veneers showing occlusal stress peaks 17–29% higher than composite resin. The estimated risk of fracture was decreased for ultrathin composite resin occlusal veneers, which correlated with the existing validation data. SignificanceUltra-thin composite resin (MZ100) and lithium disilicate (e.max CAD) occlusal veneers represent a conservative alternative to traditional onlays and complete coverage crowns for the treatment of severe erosive lesions in the posterior dentition.

Novel-design ultra-thin CAD/CAM composite resin and ceramic occlusal veneers for the treatment of severe dental erosion

Ultra-thin bonded posterior occlusal veneers represent a conservative alternative to traditional inlays and complete coverage crowns for the treatment of severe erosive lesions. There is a lack of data regarding selection of the most appropriate material and its influence on fatigue resistance, which may affect restoration longevity. The purpose of this study was to assess the influence of CAD/CAM restorative material (ceramic vs. composite resin) on fatigue resistance of ultra-thin occlusal veneers. A standardized nonretentive tooth preparation (simulating advanced occlusal erosion) was applied to 40 extracted molars including removal of occlusal enamel, and immediate dentin sealing (Optibond FL). All teeth were restored with a 0.6 mm-thick occlusal veneer (Cerec3 chairside CAD/CAM system). Reinforced ceramics (Empress CAD and e.max CAD) and composite resins (Paradigm MZ100 and XR (experimental blocks)) were used to mill the restorations (n=10). The intaglio surfaces were HF-etched and silanated (reinforced ceramics) or airborne-particle abraded and silanated (composite resins). Preparations were airborne-particle abraded and etched before restoration insertion. All restorations were adhesively luted with preheated Filtek Z100. Cyclic isometric loading was applied at 5 Hz, beginning with a load of 200N (x5,000), followed by stages of 400, 600, 800, 1000, 1200 and 1,400N at a maximum of 30,000 cycles each. The number of cycles at initial failure (first cracks) was recorded. Specimens were loaded until catastrophic failure (lost restoration fragment) or to a maximum of 185,000 cycles. Groups were compared using the life table survival analysis (α=.008, Bonferroni-method). Empress CAD and e.max CAD initially failed at an average load of 500N and 800N, respectively with no specimen withstanding all 185,000 load cycles (survival 0%); with MZ100 and XR the survival rate was 60% and 100%, respectively. Both composite resins (MZ100 and XR) increased the fatigue resistance of ultra-thin occlusal veneers (P<.001) when compared to the ceramics evaluated (Empress CAD and e.max CAD).

Skeletal pathology of a high-ranking official from Thrace (Turkey, last quarter of the 4th century BC)

A male human skeleton from Thrace dated at around 320 BC was found in a wealthy tomb 12 km from what is now Tekirdağ, Turkey. The occupant of the tomb died at the age of 40–45 years and has a pathologic left humerus caused most probably by traumatic injury. It is 9 cm shorter than the right humerus. A drainage fistula penetrating into the medullary cavity occurs at its proximal end. Due to severe arthritic destruction, the left humeral head has completely lost normal articulation, with the glenoid cavity of the left scapula displaying, in turn, severe erosive lesions and important reduction in its articular surface. A marked abscess is discernible bilaterally on the chondro-costal sternal end. The individual also has a hip with a total sacroiliac joint fusion and shows slight or moderately developed exostoses on different parts of his skeleton. These joint destructions most likely indicate that he suffered from chronic osteomyelitis and septic arthritis. Copyright © 2005 John Wiley & Sons, Ltd.

バルーンカテーテルによる食道拡張術が奏効したはん痕性食道狭窄の１例

Swallowing a corrosive, especially an alkali agent often cause a severe esophageal stricture which is usually very difficult to be treated. In this paper, a case of esophageal stricture treated by a balloon dilator was reported.The patient was 46-year-old female complaining of swallowing difficulty. She had an episode of drinking sodium hydroxide in childhood by mistake. She had been diagnosed as esophageal stricture by a previous doctor. She underwent surgical treatments twice without any satisfactory result. She was referred to our clinic. Esophagography and endoscopy revealed two stenotic lesions in her lower esophagus. Under hospitalization, she was treated by a balloon dilator inflated at 2 atmospheric pressure. The dilator was inserted through her mouth and inflated four times a day. Each trial was fifteen minutes. Although the treatment was continued for a week, there was little improvement. Besides, severe erosive lesions around the stenosis were detected. Considering the risk of an esophageal perforation by frequent trial of insertion, the balloon dilator was inserted through the nose and kept in the esophagus. Inflation of the balloon for sixty minutes a day was performed for consecutive twenty days. After two courses of this treatment, the stenosis appeared to be dilated adequately.The method using a balloon dilator may require a long period to improve an esophageal stricture, compared with other methods such as, laser resection or surgical removal. This method, however, is still useful because its safety and repeatability.