Mechanisms of Bone Resorption in Periodontitis.

Alveolar bone loss is a hallmark of periodontitis progression and its prevention is a key clinical challenge in periodontal disease treatment. Bone destruction is mediated by the host immune and inflammatory response to the microbial challenge. However, the mechanisms by which the local immune response against periodontopathic bacteria disturbs the homeostatic balance of bone formation and resorption in favour of bone loss remain to be established. The osteoclast, the principal bone resorptive cell, differentiates from monocyte/macrophage precursors under the regulation of the critical cytokines macrophage colony-stimulating factor, RANK ligand, and osteoprotegerin. TNF-α, IL-1, and PGE2 also promote osteoclast activity, particularly in states of inflammatory osteolysis such as those found in periodontitis. The pathogenic processes of destructive inflammatory periodontal diseases are instigated by subgingival plaque microflora and factors such as lipopolysaccharides derived from specific pathogens. These are propagated by host inflammatory and immune cell influences, and the activation of T and B cells initiates the adaptive immune response via regulation of the Th1-Th2-Th17 regulatory axis. In summary, Th1-type T lymphocytes, B cell macrophages, and neutrophils promote bone loss through upregulated production of proinflammatory mediators and activation of the RANK-L expression pathways.

Prevalence of clinically relevant oral mucositis in outpatients receiving myelosuppressive chemotherapy for solid tumors.

PURPOSE: Chemotherapy-induced oral mucositis (CIOM) is a common side effect of cancer therapy that may lead to significant morbidity and interfere with the treatment plan. The present prospective, cross-sectional study intended to describe the prevalence of clinically relevant CIOM (CRCIOM) in outpatients receiving chemotherapy for solid tumors. METHODS: Intra-oral assessments were performed on 298 consecutively recruited patients, who had undergone at least 14 days of chemotherapy for solid tumors in our outpatient oncology department. The presence of CIOM was evaluated using the Oral Mucositis Assessment Scale. CRCIOM was defined as the presence of ulcers (≥ 1 cm(2)), severe erythema, and/or inability to eat solid foods (WHO grades 2-4). Furthermore, the current levels of oral hygiene and oral health were measured. RESULTS: A low prevalence (18 patients, 6%) of CRCIOM was found in the investigated patient collective, including 1% of patients with severe (WHO grade 3/4) CIOM. In the CRCIOM group, 16 patients were male, and two were female; 8 patients with CRCIOM had received head and neck radiotherapy. A higher prevalence of CRCIOM was found in smoking patients (12.7% vs. 4.5%, p < 0.05) and in the patients who have not had a dental checkup within the preceding 12 months (11.2% vs. 3.0%, p < 0.01). Diabetes mellitus and low WBC appeared not to be associated with higher CRCIOM rates. The plaque and gingival indexes were significantly increased (p < 0.01) in the CRCIOM group. CONCLUSIONS: Although CRCIOM was a rare event in the investigated patient population, our results emphasize that pre-treatment dental therapy and primary preventive measures (including oral hygiene instructions) can be improved. Before starting chemotherapy, increased awareness of individual risk factors, such as male sex, tobacco smoking, low dental checkup frequency, poor oral hygiene, and a reduced oral health status, could help to prevent CRCIOM.

Labial piercing and localized periodontal destruction - partial periodontal regeneration following periodontal debridement and free gingival graft.

Localized periodontal destruction has been reported as a rare complication of intraoral piercings. The purpose of this case report was to illustrate the destructive nature of a lip stud and to describe the successful treatment of this case. The lip stud was removed and supra- and subgingival debridement was performed. Because of a shallow vestibule, the absence of keratinized gingiva, and the strong frenulum insertion at the gingival margins, a free gingival graft was placed. Subsequently the patient demonstrated a significant amount of osseous regeneration and partial coverage of the recession, which has been clinically and radiographically (computed tomography) documented.

Quantification of bone resorption in the interforaminal region of the atrophic mandible.

PURPOSE: This anatomic study was undertaken to examine the effects of atrophy on bone quantity and quality in the mandibular interforaminal region. MATERIALS AND METHODS: Three sections were made from each jaw studied, and each section was measured by means of a morphometric software program (Artma-Biomed, Vienna, Austria). The mandibular specimens were grouped according to the classification of Cawood and Howell and also according to that of Lekholm and Zarb. RESULTS: The macromorphometric measurements revealed that mandibular atrophy may cause the loss of up to 60% of the original bone mass. As the maximum width remained relatively consistent in all jaw sections, it can be assumed that the reduction in total area of each jaw section results from a reduction in mandibular height. The compact and cancellous bone portions were equally affected by resorption. The assessment of bone quality showed that most mandibles displayed a thick cortical compartment, especially inferiorly and lingually, with variations in the amount of cancellous bone. There was a clear predominance of bone types 2 and 3. DISCUSSION AND CONCLUSION: The interforaminal region of the mandible appears to be the site of choice for implantation, since it can be expected that the bone structure is well suited to provide the necessary stability even in severely atrophic mandibles. As the degree of alveolar ridge resorption does not depend on the patient's age but on the time elapsing postextraction, implants should be placed as soon as possible after tooth loss in order to avoid excessive resorption.