Methods for the measurement and characterization of erosion in enamel and dentine

The advantages, limitations and potential applications of available methods for studying erosion of enamel and dentine are reviewed. Special emphasis is placed on the influence of histological differences between the dental hard tissue and the stage of the erosive lesion. No method is suitable for all stages of the lesion. Factors determining the applicability of the methods are: surface condition of the specimen, type of the experimental model, nature of the lesion, need for longitudinal measurements and type of outcome. The most suitable and most widely used methods are: chemical analyses of mineral release and enamel surface hardness for early erosion, and surface profilometry and microradiography for advanced erosion. Morphological changes in eroded dental tissue have usually been characterised by scanning electron microscopy. Novel methods have also been used, but little is known of their potential and limitations. Therefore, there is a need for their further development, evaluation, consolidation and, in particular, validation.

Quality and quantity of bone following alveolar distraction osteogenesis in the human mandible

PURPOSE: The purpose of this prospective study on humans were to evaluate (a) the clinical outcome of alveolar distraction osteogenesis for the correction of vertically deficient edentulous mandibular ridges, (b) the clinical outcome of dental implants placed in the distracted areas, and (c) the quality and quantity of the bone that had formed in the distraction gap. MATERIAL AND METHODS: Seven patients presenting vertically deficient edentulous ridges were treated by means of distraction osteogenesis with an intraoral alveolar distractor. Approximately 3 months after consolidation of the distracted segments, 20 ITI solid screw SLA implants were placed in the distracted areas. Three to 4 months later, abutments were connected and prosthetic loading of the implants started. During implant site preparation, bone biopsies were taken at the implant sites with trephine burrs for histologic and histometric analyses. RESULTS: The mean follow-up after the initial prosthetic loading was 18 months (range 12-24 months). The mean bone gain obtained at the end of distraction was 7 mm (range 5-9 mm). The cumulative success rate of implants 2 years after the onset of prosthetic loading was 95%, whereas the survival rate of implants was 100%. The newly formed bone consisted of woven bone reinforced by parallel-fibered bone with bone marrow spaces between the bone trabeculae. The bone area fraction in the distraction region ranged from 21.6% to 57.8% (38.5+/-11.7%). DISCUSSION AND CONCLUSIONS: Results from this study showed that (a) distraction osteogenesis is a reliable technique for the correction of vertically deficient edentulous ridges, (b) the regenerated bone withstood the functional demands of implant loading, (c) survival and success rates of implants placed in the distracted areas were consistent with those of implants placed in native bone, and (d) there is sufficient bone volume and maturity in the distracted region for primary stability of the implant.

Multiple myeloma-associated amyloidoma of the sacrum: case report and review of the literature.

Study Design Case report. Objectives With only two previously reported cases, localized amyloidosis of the sacrum is extremely rare. Here we report a 64-year-old woman with a large osteolytic lesion accompanied by weakness and paresthesia of the right leg and difficulties in bladder control. Methods Fine needle biopsy and standard staging procedures revealed a primary solitary amyloidoma that was treated with intralesional resection, lumbopelvic stabilization, and consolidation radiotherapy. Results Clinical follow-up revealed the diagnosis of multiple myeloma 9 months after initial treatment. At 12 months, no local recurrence has occurred, the neurologic symptoms have resolved, and the systemic disease is in remission. Conclusions Intralesional resection with adjuvant radiotherapy of the amyloidoma achieved good local tumor control with limited morbidity.