Guided Bone Regeneration Using Barrier Membrane in Dental Applications.

Guided bone regeneration (GBR) is a widely used technique in preclinical and clinical studies due to its predictability. Its main purpose is to prevent the migration of soft tissue into the osseous wound space, while allowing osseous cells to migrate to the site. GBR is classified into two main categories: resorbable and non-resorbable membranes. Resorbable membranes do not require a second surgery but tend to have a short resorption period. Conversely, non-resorbable membranes maintain their mechanical strength and prevent collapse. However, they require removal and are susceptible to membrane exposure. GBR is often used with bone substitute graft materials to fill the defect space and protect the bone graft. The membrane can also undergo various modifications, such as surface modification and biological factor loading, to improve barrier functions and bone regeneration. In addition, bone regeneration is largely related to osteoimmunology, a new field that focuses on the interactions between bone and the immune system. Understanding these interactions can help in developing new treatments for bone diseases and injuries. Overall, GBR has the potential to be a powerful tool in promoting bone regeneration. Further research in this area could lead to advancements in the field of bone healing. This review will highlight resorbable and non-resorbable membranes with cellular responses during bone regeneration, provide insights into immunological response during bone remodeling, and discuss antibacterial features.

A Novel Modified-Curcumin Promotes Resolvin-Like Activity and Reduces Bone Loss in Diabetes-Induced Experimental Periodontitis.

PURPOSE: Clinically, it is challenging to manage diabetic patients with periodontitis. Biochemically, both involve a wide range of inflammatory/collagenolytic conditions which exacerbate each other in a "bi-directional manner." However, standard treatments for this type of periodontitis rely on reducing the bacterial burden and less on controlling hyper-inflammation/excessive-collagenolysis. Thus, there is a crucial need for new therapeutic strategies to modulate this excessive host response and to promote enhanced resolution of inflammation. The aim of the current study is to evaluate the impact of a novel chemically-modified curcumin 2.24 (CMC2.24) on host inflammatory response in diabetic rats. METHODS: Type I diabetes was induced by streptozotocin injection; periodontal breakdown then results as a complication of uncontrolled hyperglycemia. Non-diabetic rats served as controls. CMC2.24, or the vehicle-alone, was administered by oral gavage daily for 3 weeks to the diabetics. Micro-CT was used to analyze morphometric changes and quantify bone loss. MMPs were analyzed by gelatin zymography. Cell function was examined by cell migration assay, and cytokines and resolvins were measured by ELISA. RESULTS: In this severe inflammatory disease model, administration of the pleiotropic CMC2.24 was found to normalize the excessive accumulation and impaired chemotactic activity of macrophages in peritoneal exudates, significantly decrease MMP-9 and pro-inflammatory cytokines to near normal levels, and markedly increase resolvin D1 (RvD1) levels in the thioglycolate-elicited peritoneal exudates (tPE). Similar effects on MMPs and RvD1 were observed in the non-elicited resident peritoneal washes (rPW). Regarding clinical relevance, CMC2.24 significantly inhibited the loss of alveolar bone height, volume and mineral density (ie, diabetes-induced periodontitis and osteoporosis). CONCLUSION: In conclusion, treating hyperglycemic diabetic rats with CMC2.24 (a tri-ketonic phenylaminocarbonyl curcumin) promotes the resolution of local and systemic inflammation, reduces bone loss, in addition to suppressing collagenolytic MMPs and pro-inflammatory cytokines, suggesting a novel therapeutic strategy for treating periodontitis complicated by other chronic diseases.

Multistepped Drill Design for Single-Stage Implant Site Preparation: Experimental Study in Type 2 Bone.

PURPOSE: To evaluate an experimental multistepped drill for single-stage implant site preparation by means of real-time analysis of thermal variations during and postdrilling, and by implant stability evaluation. MATERIALS AND METHODS: Temperature and time were recorded in real time by paired microprobe thermocouples during simulated osteotomy in type 2 bone similes at the cortical and cancellous zones. Three different drilling groups with a new multistepped drill design were compared: Control (2-mm diameter pilot drill + 3.3-mm three-stepped drill + 4.1-mm three-stepped drill); Test A (3.3-mm three-stepped drill); and Test B (4.1-mm three-stepped drill). Implants were inserted, and implant stability was evaluated with the Perio Test Value (PTV). Two-way anova was used to test the independent effects of osteotomy and implant diameter on temperature and stability. RESULTS: All the drills induced thermal changes without significant differences between groups (p > .05). Drilling in cortical bone produced significant increase of the temperatures in a range of 1.8 ± 0.9°C compared with drilling in cancellous bone (p < .05). ΔT temperatures were significantly higher for test groups in cortical and cancellous bone (p < .05); ΔT10 for all groups showed a reduction of the temperature in a range of 1.7 ± 0.3°C without significant differences between groups (p > .05); the mean time to accomplish drilling was significantly longer in the control group (p < .05); test groups took 10 ± 0.3 seconds less to reach the required drilling depth. PTV values were higher in test groups compared with controls (p < .05). CONCLUSIONS: The multistepped drills used for single-stage implant site preparation Increase temperature as in comparison with a conventional incremental protocol; Induce the temperature increment in cortical bone compared with the cancellous bone; Reduce drilling time when a multistepped drill is used alone; and Increase implant stability twofold compared with a conventional incremental protocol.

Evolution of a humanitarian dental mission to Madagascar from 1999 to 2008.

In this article, we report on the evolution of a series of dental outreach missions sponsored by Stony Brook University to remote areas of Madagascar over a nine-year period. The project evolved from one dental resident performing only dental extractions in 1999 to a team comprised of two dentists, six third-year dental students, and two dental assistants performing dental restorations, extractions, and endodontic procedures using digital radiographic equipment in 2008. The ability during the latest mission to utilize digital radiography in remote areas lacking running water, electricity, and dental facilities significantly enhanced the range and efficacy of dental procedures. This long-term project offered senior dental students and residents from Stony Brook University's School of Dental Medicine an educationally valuable opportunity to engage in international dental outreach and to make a significant contribution to the improvement of oral health in the underserved rural communities of Madagascar.

Long-term management of a child with regional odontodysplasia: a case report.

Regional odontodysplasia, or "ghost teeth," is a dental abnormality derived from both epithelial and mesenchymal components of the tooth bud. Teeth within a particular quadrant are affected. Affected teeth usually have thin enamel and dentin of poor quality with shortened roots, open apices, or enlarged pulp chambers. The permanent teeth and maxillary arch are observed to be more severely affected than primary teeth and the mandibular arch (ratio=1.6:1), respectively. Eruption of the affected teeth is delayed or may not happen. The cause of the phenomenon is unknown. Since this problem affects both dentitions and can involve multiple care disciplines, patients often require oral care over a long period of time. The purpose of this report was to present the management of a case from initial presentation at the age of 20 months to a final prosthesis completion at the age of 22 years. The long-term treatment may involve a pediatric dentist, orthodontist, oral surgeon, and prosthodontist.

Update on the distribution of oral and maxillofacial surgeons 1995 to 2006.

A review of the 2006 and past American Dental Association (ADA) studies on the distribution of dentists provides updated information on the evolving number and distribution of oral and maxillofacial surgeons. Despite an overall increase in the number of oral surgeons, differences continue in practitioner-to-population ratios in the various geographic areas.

Chemically modified tetracycline (CMT-8) and estrogen promote wound healing in ovariectomized rats: effects on matrix metalloproteinase-2, membrane type 1 matrix metalloproteinase, and laminin-5 gamma2-chain.

Estrogen deficiency is associated with impaired cutaneous wound healing. Remodeling of the extracellular matrix in wound healing involves the action of matrix metalloproteinases on basement membrane zone components, especially laminin-5. We studied the effects of estrogen and a potent matrix metalloproteinase inhibitor, chemically modified non-antimicrobial tetracycline, CMT-8, on wound healing in ovariectomized rats. At the tissue level, laminin-5 gamma2-chain expression was decreased and the migration-inductive 80 kDa form of laminin-5 gamma2-chain was absent in ovariectomized rats when compared with sham and CMT-8- or estrogen-treated ovariectomized animals as detected by Western blotting. The highest levels of gelatinolytic activity (matrix metalloproteinase-2 and -9) were found in sham animals. Levels were reduced in ovariectomized rats and were lowest after treating ovariectomized rats with CMT-8 or estrogen as analyzed by functional activity assay and zymography. The total amount of membrane type 1-matrix metalloproteinase was unchanged in all groups. We conclude that CMT-8 and estrogen can promote wound healing in ovariectomized rats, not only by normalizing wound bed total collagen content and structure, but also by recovering the expression and processing of key molecules in wound healing, i.e., laminin-5 gamma2-chain. This study shows, for the first time, the role of estrogen and CMT-8 in laminin-5 gamma2-chain modulation in vivo.