Primary bone

About: Primary bone is a research topic. Over the lifetime, 1335 publications have been published within this topic receiving 29421 citations.

De novo alveolar bone formation adjacent to endosseous implants

Abstract: Objective: To describe a model for the investigation of different phases of wound healing that are involved in the process resulting in osseointegration. Material and methods: The implants used for the study of early healing had a geometry that corresponded to that of a solid screw implant with an SLA surface configuration. A circumferential trough had been prepared within the thread region (intra-osseous portion) that established a geometrically well-defined wound compartment. Twenty Labrador dogs received 160 experimental devices totally to allow the evaluation of healing between 2 h and 12 weeks. Both ground sections and decalcified sections were prepared from different implant sites. Results: The experimental chamber used appeared to be conducive for the study of early phases of bone formation. The ground sections provided an overview of the various phases of soft and hard tissue formation, while the decalcified, thin sections enabled a more detailed study of events involved in bone tissue modeling and remodeling. The initially empty wound chamber became occupied with a coagulum and a granulation tissue that was replaced by a provisional matrix. The process of bone formation started already during the first week. The newly formed bone present at the lateral border of the cut bony bed appeared to be continuous with the parent bone, but woven bone was also found on the SLA surface at a distance from the parent bone. This primary bone that included trabeculae of woven bone was replaced by parallel-fibered and/or lamellar bone and marrow. Between 1 and 2 weeks, the bone tissue immediately lateral to the pitch region, responsible for primary mechanical stability of the device, became resorbed and replaced with newly formed viable bone. Despite this temporary loss of hard tissue contact, the implants remained clinically stable at all times. Conclusion: Osseointegration represents a dynamic process both during its establishment and its maintenance. In the establishment phase, there is a delicate interplay between bone resorption in contact regions (between the titanium body and mineralized bone) and bone formation in ‘contact- free’ areas. During the maintenance phase, osseointegration is secured through continuous remodeling and adaptation to function.

The hazards of biopsy in patients with malignant primary bone and soft-tissue tumors.

Abstract: This study was performed by the Musculoskeletal Tumour Society using questionnaires to assess the following: • The accuracy of biopsy in making a diagnosis • The incidence of complications associated with the biopsy procedure • The effects of errors in diagnosis and of complications on the treatment of patients • Whether these problems occurred with greater frequency when the initial biopsy was performed in a referring institution or in a specialist treating centre Each member of the Society submitted data on 20 sequential, unselected, newly diagnosed patients with malignant primary tumours of bone or soft tissue who underwent a biopsy and then a defi nitive procedure. The study received data from 20 orthopedic surgeons in 16 treating centres. Information on 329 patients included a wide range of diagnoses (but generally conforming to the distribution of these tumours in the general population). The mean age of the patients was 36.5 years (range, 2 weeks to 83 years). Two hundred and twenty two lesions were bone primaries and 107 were derived from soft tissue. One hundred and forty three tumours were biopsied in the referring institution and 171 in the treating centre. The authors demonstrated 60 (18.2 %) major errors in diagnosis and 34 (10.3 %) non-representative or technically poor biopsies. Fifty-seven patients (17.3 %) encountered problems in the skin, soft tissue, or bone following biopsy and the optimum treatment plan had to be altered as a result of problems related to the biopsy in 60 patients (18.2 %). In 15 patients (4.5 %) an unnecessary amputation was performed as a result of problems with the biopsy, and in 28 patients (8.5 %) the prognosis and outcome were considered to have been adversely affected. Patients undergoing a biopsy at the referring institution experienced biopsy-related problems three to fi ve times more frequently than those undergoing biopsy at a treating centre. Given these fi ndings, the authors recommend that the biopsy should be planned as carefully as defi nitive surgery. In particular, careful attention should be paid to the following: • Asepsis, skin-handling, haemostasis, and wound closure • Precise skin incision placement, which will not compromise subsequent surgery. • The tissue obtained should be suffi cient in volume and suffi ciently representative of the lesion that the pathologist can provide a defi nitive diagnosis. If the surgeon or the institution is not prepared to perform accurate diagnostic studies or proceed with defi nitive treatment for these patients, patients should be referred to a treating centre prior to biopsy. The Hazards of Biopsy in Patients with Malignant Primary Bone and SoftTissue Tumors

Bone metastases: an overview

Abstract: Bone is a frequent site of metastases and typically indicates a short-term prognosis in cancer patients. Once cancer has spread to the bones it can rarely be cured, but often it can still be treated to slow its growth. The majority of skeletal metastases are due to breast and prostate cancer. Bone metastasis is actually much more common than primary bone cancers, especially in adults. The diagnosis is based on signs, symptoms and imaging. New classes of drugs and new interventions are given a better quality of life to these patients and improved the expectancy of life. It is necessary a multidisciplinary approach to treat patients with bone metastasis. In this paper we review the types, clinical approach and treatment of bone metastases.

Physical and biological aspects of fracture healing with special reference to internal fixation.

Abstract: Fracture healing is a repair process of a mechanical discontinuity loss of force transmission, and pathological mobility of bone. Through a sequence of changes of tissue development and geometry, the original structural integrity is restored. The recovery of rigidity and strength is related to tissue differentiation. In unified theory of non-operative and operative stabilized fractures, the mechanics of primary bone healing involves a complex interplay of physical and biological factors. The different patterns of bone repair respond to physical influences including strain tolerance.