Cell transplantation in wounded mixed connective tissues.
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Direct transplantation of multipotent precursor cells into the periodontium could provide a therapeutic approach for restoring periodontal tissues destroyed by periodontitis or trauma. To improve the understanding of cell migration, proliferation, and differentiation, we used a rodent model combining orthodontic tooth movement and transplantation of Lac-Z-positive murine-cultured periodontal ligament (PL) or femur-derived bone marrow precursor cells into a defined mandibular wound site, thus promoting tissue regeneration in wounded periodontium. Our results show that in orthodontically traumatized tissues, transplanted PL and bone marrow cells migrated systemically, contributing to the repopulation of sites with reduced cell/matrix density. The transplanted PL cells proliferated in adjacent alveolar bone marrow spaces, thus migrating to vascular tissues in the PL. The capillary walls in the PL serve as delivery sites for these cells and other marrow-derived hematopoietic cells, including monocytes. The transplanted marrow cells, extracted from femur of transgenic (TgR) mice exhibited similar behavior to those of transplanted PL cells, showing high proliferative activity in alveolar marrow as well as intensive repopulating capacity in wounded periodontium. On the other hand, the buccal skin fibroblasts failed to migrate and home effectively and thus the transplantation of these cells had no effect on periodontium regeneration. Based on these results, we conclude that the transplanted PL and bone marrow cells migrate systemically and following a cyclical process of growth and development and differentiate into PL fibroblasts, osteoblasts, and cementoblasts, thereby contributing to periodontal regeneration. (+info)
Bone grafting simultaneous to implant placement. Presentation of a case.
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Bone defects at mandibular alveolar crest level complicate the placement of dental implants in the ideal location. Surgical reconstruction using autologous bone grafts allows implant fixation in an esthetic and functional manner. We describe a patient with large mandibular bone loss secondary to periodontal inflammatory processes. Reconstruction of the mandibular alveolar process was carried out using onlay block bone grafts harvested from the mandible. The grafts were stabilized by positioning the dental implants through them--a procedure that moreover afforded good primary implant fixation. After two years of follow-up the clinical and radiological outcome is good. In the lower jaw, where bone regeneration is complicated, we were able to achieve good results in this patient--minimizing the corresponding waiting time by grafting and placing the implants in the same surgical step. (+info)
How predictable are periodontal regenerative procedures?
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Periodontal regeneration has become one of the primary objectives of periodontal therapy. The resulting scientific endeavours have elucidated modes of periodontal wound healing, the growth of periodontal cells and their association with the surrounding matrix, and growth-promoting factors. The periodontal regeneration industry is producing better and more expensive devices, but the criteria for evaluating their success have not progressed to the same extent. Although clinical measurements of attachment level and probing depths, along with radiography, are good methods of evaluating tooth survival and prognosis, they do not indicate true biological regeneration. In addition, the regeneration industry may encourage the overuse of allografts and alloplasts which may serve as an impediment to simple wound healing. This review is a critical assessment of the clinical use of various regenerative tools, specifically bone replacements and membranes. The future of the regeneration industry may depend on the merging of various technologies and biological concepts, including the possible use of biological barriers, various bone and periodontal growth inducers, and artificial matrices that will attract or carry the cells necessary for regeneration. (+info)
The association between periodontal disease and joint destruction in rheumatoid arthritis extends the link between the HLA-DR shared epitope and severity of bone destruction.
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OBJECTIVE: To evaluate a possible association between wrist and periodontal destruction in rheumatoid arthritis, and between periodontal destruction, dry mouth, and labial salivary gland biopsy and the contribution of genetic factors (the shared epitope (SE) and IL1B (+3954) or TNFA (-238 or -308) gene polymorphisms). METHODS: 147 patients with rheumatoid arthritis were enrolled. Periodontal damage was defined according to the Hugoson and Jordan criteria on panoramic dental x rays. Typing for the SE and cytokine polymorphisms was undertaken by enzyme linked oligosorbent assay. Odds ratios (OR), relative risk (RR), and chi2 values were calculated to quantify associations. RESULTS: An association was observed between wrist and periodontal bone destruction (chi2=11.82; p<0.001): 63 patients had both wrist and periodontal destruction, 31 had wrist destruction alone, 20 had periodontal destruction alone, and 33 had no destruction at either site. An association was seen between a positive labial salivary gland biopsy and periodontal bone destruction (RR=2.73 (95% CI, 1.35 to 5.51), p<0.01, n=41) or wrist bone destruction (RR=4.52 (1.96 to 10.45), p<0.001, n=41). The SE was associated with wrist bone destruction (OR=2.5 (1.16 to 5.42), p<0.05) and periodontal bone destruction (OR=2.2 (1.04 to 4.84), p<0.05). No association was found between the selected cytokine polymorphisms and bone destruction. CONCLUSIONS: A strong association was found between wrist and periodontal bone destruction. The destruction risk was further increased in patients with sicca syndrome. The SE appears to be a severity genetic marker for both wrist and periodontal bone destruction. (+info)
Resolution of furcation bone loss after non-surgical root canal treatment: application of a peptidase-detection kit for treatment of type I endoperiodontal lesion.
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Here, we report the management of a type I endoperiodontal lesion with furcation bone loss. A 59-year-old female attended our hospital with the chief complaint of mobility of tooth 46 and recurrent gingival swelling around the tooth. She previously received dental treatment from two dentists, but her condition did not improve. The tooth manifested the symptoms of typical periodontitis, such as gingival swelling, tooth mobility, pus discharge from the periodontal pocket and furcation bone loss. The tooth had no caries and the pulp reacted to an electric pulp test. Careful examination of the gingiva revealed traces of dental fistula. X-ray examination via a gutta percha inserted into the fistula revealed that furcation bone loss was associated with the periapical lesion. We diagnosed a type I endoperiodontal lesion, and applied Periocheck, a detection kit for peptidase-producing bacteria, to check for decreases in bacteria in the furcation and root canals. Soon after non-surgical root canal treatment, the condition of tooth 46 improved without periodontal treatment. After confirming a negative score with Periocheck, the root canal was filled. After 3 months, the furcation bone loss was on the way to recovery. These results indicate that proper diagnosis and confirmation of a decrease in root canal bacteria are important for treating endoperiodontal lesions. (+info)
Bacterial-responsive B lymphocytes induce periodontal bone resorption.
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Host immune responses play a key role in periodontal diseases. We have found that B lymphocytes in human periodontal lesions bear abundant receptor activator of NF-kappaB ligand (RANKL), a major factor in the regulation of osteoclast differentiation. The purpose of this study was to evaluate Actinobacillus actinomycetemcomitans-responsive B lymphocytes in their level of RANKL expression and their effects on periodontal bone resorption. Congenitally athymic Rowett rats received injections of formalin-fixed A. actinomycetemcomitans into the gingival papillae, and donor B cells from normal rats immunized with A. actinomycetemcomitans were transferred via tail vein injection. We demonstrated that B cells from A. actinomycetemcomitans-immunized animals had greater levels of RANKL expression and induced a significantly higher level of osteoclast differentiation from RAW 264.7 cells than did nonimmune B cells that were not Ag specific. This activity was eliminated by incubation with the RANKL decoy receptor osteoprotegerin fusion protein. A. actinomycetemcomitans-binding B cell (ABB) and RANKL-expressing B cells were recovered from the gingival tissues of recipient rats transferred with ABB, but not from recipients of PBS nonimmune B cells or A. actinomycetemcomitans nonbinding B cells. Also, recipients of ABB exhibited increased osteoclast formation on the alveolar bone surface and significant periodontal bone resorption. This effect was antagonized by injection of osteoprotegerin fusion protein into the local gingival tissues. In summary, this study suggests that B lymphocytes can contribute to increased periodontal bone resorption in the absence of T lymphocytes. This effect is associated with the up-regulation of RANKL expression. (+info)
RvE1 protects from local inflammation and osteoclast- mediated bone destruction in periodontitis.
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Periodontitis is a well-appreciated example of leukocyte-mediated bone loss and inflammation that has pathogenic features similar to those observed in other inflammatory diseases such as arthritis. Resolvins are a new family of bioactive products of omega-3 fatty acid transformation circuits initiated by aspirin treatment that counter proinflammatory signals. Because it is now increasingly apparent that local inflammation plays a critical role in many diseases, including cardiovascular disease, atherosclerosis, and asthma, experiments were undertaken to evaluate the actions of the newly described EPA-derived Resolvin E1 (RvE1) in regulation of neutrophil tissue destruction and resolution of inflammation. The actions of an aspirin-triggered lipoxin (LX) analog and RvE1 in a human disease, localized aggressive periodontitis (LAP), were determined. Results indicate that neutrophils from LAP are refractory to anti-inflammatory molecules of the LX series, whereas LAP neutrophils respond to RvE1. In addition, RvE1 specifically binds to human neutrophils at a site that is functionally distinct from the LX receptor. Consistent with these potent actions, topical application of RvE1 in rabbit periodontitis conferred dramatic protection against inflammation induced tissue and bone loss associated with periodontitis. (+info)
Compressive osteotomes for expansion and maxilla sinus floor lifting.
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AIM: The aim of this article is to assess the efficiency of the technique for the posterior alveolar expansion and elevation of the upper maxillary alveolar ridge through the use of compressive osteotomes (Quirurgical Bontempi, Espana) which have been specifically designed for Osseotite NT and Osseotite NT Certain of 3i implants (Implants Innovations, USA). MATERIALS AND METHODS: 24 adult patients (16 female and 12 male), who were selected according to Albrektsson's inclusion and exclusion criteria, took part in the study. All the patients presented bone deficiency in the width and height of the upper maxilla. 48 Osseotite implants were performed (four Osseotite Standard; six Osseotite NT; 38 NT Certain (3i, Implants Innovations, CA, USA)). Implant diameters were 4 mm in 44 cases and 5 mm in 4 cases with lengths varying between 11.5 (n = 4) and 13 mm (n = 44). The alveolar ridges of the 24 patients had initial widths from 1.5 mm to 5 mm and heights between 5 and 13 mm. RESULTS: The data obtained were analysed using the SPSS 11.0 program. In the 48 areas treated with immediate implants, an increase in bone height of 6.75 mm -/+ 1.25 mm was achieved. In the case of the alveolar expansion for the 48 implants, the average was 3.2 mm -/+ 0.15 mm. CONCLUSIONS: The technique for alveolar expansion and elevation of the upper maxilla with compressive osseotomes can lead to a 100% success rate after a 9-month follow-up of the implants and insertion of prostheses. It is a highly predictable surgical procedure which allows implants to be performed at the same time as surgery, thus reducing the number of such interventions while recovering aesthetic and functional losses in the patient. (+info)