Publications in May 2015

166 articles about chitosan were published in May 2015. In the rank of nations scientists from China gained with 39 publications the leading position, followed by India (16), the US (12) and Italy (11). The research priorities focused on nanoparticles, evaluation studies and pharmaceutical preparations.

Table: Top 5 journals dealing with chitosan-related articles in May 2015
Quelle: GoPubMed

This month the topic of our literature review is the application of chitosan in odontology. We present promising studies in the fields of periodontal guided tissue regeneration and coatings at implant surfaces.

Acidic pH restistance of grafted chitosan on dental implant

Campos, D. M. et al.; Odontology 103(2):210-7. doi: 10.1007/s10266-014-0162-5.

Titanium and titanium alloys are key dental implants. Despite their great biocompatibility, surrounded tissue integration and mechanical properties, bacterial infection could cause implant removal. Therefore, the authors of this investigation studied natural bioactive polymers as resistant antimicrobial coating. Surface functionalization was done by triethoxysilylpropyl succinic anhydride (TESPSA), as organic coupling agent, and chitosan.
Results:

• TESPSA strengthen the adhesivity of chitosan on titanium
• TESPSA/chitosan-coating is chemical resistant at pH 5 and pH3
• normal proliferative capacity of human gingival fibroblasts on TESPSA/chitosan coated surface --> nontoxic

Conclusion: After silanation of TESPSA on titanium chitosan was covalent bound via stable peptide bond on the titanium surface. The TESPSA/chitosan coated surface showed higher adhesivity and as well chemical resistibility at pH 5 and pH3 in artificial saliva. Cytocompatibility tests with human gingival fibroblasts demonstrated normal cell proliferation. Their cytocompatibility and as well their resistibility under drastic environments such as the acidic environment in the oral cavity makes TESPSA/chitosan-coatings to promising applications in implantology.

Source: http://www.ncbi.nlm.nih.gov/pubmed/24972881

Freeze gelated porous membranes for periodontal tissue regeneration

Qasim, S. B. et al.; Acta Biomaterialia. doi: 10.1016/j.actbio.2015.05.001. [Epub ahead of print] Mai 2015

Destructive forms of periodontal disease lead to damage of the supporting tissues of teeth. Treatment of these diseases includes the application of resorbable membranes for guided tissue regeneration. This study focuses on the development of a porous resorbable biocompatible membrane. For this purpose, the antimicrobial, wound healing and hemostatic potential of chitosan and the osteoinductive and osteoconductive properties of hydroxyapatite were combined. Membranes were produced by freeze gelation.
Membrane properties:

• interaction of chitosan and hydroxyapatite
• porosity: 85-77%
• swelling percentage: 60-80%
• support cell proliferation
• hydroxyapatite increases long term matrix deposition

Conclusion: Porous chitosan-hydroxyapatit membranes were successfully produced via freeze gelation. These membranes showed high potential in functionally guided tissue regeneration due to a porous microarchitecture, the flexibility and resilent nature during dry and wet conditions. Most tensile membranes were developed by solving chitosan in ascorbic acid. In histological studies human mesenchymal progenitor cells penetrated deep into the membranes; proving good biocompatibility.

Source: http://www.ncbi.nlm.nih.gov/pubmed/25968357