US 11,737,955 B2
Multi-functional micro and nanoparticles for use in root canal therapies
Anil Kishen, Mississauga (CA); and Annie Shrestha, Toronto (CA)
Assigned to Anil Kishen, North York (CA)
Filed by THE GOVERNING COUNCIL OF THE UNIVERSITY OF TORONTO, Toronto (CA)
Filed on Feb. 16, 2018, as Appl. No. 15/932,180.
Application 15/932,180 is a division of application No. 15/264,364, filed on Sep. 13, 2016, abandoned.
Application 15/264,364 is a continuation of application No. 14/385,596, abandoned, previously published as PCT/CA2013/000275, filed on Mar. 21, 2013.
Claims priority of provisional application 61/614,235, filed on Mar. 22, 2012.
Prior Publication US 2018/0185249 A1, Jul. 5, 2018
Int. Cl. A61K 6/00 (2020.01); A61K 6/62 (2020.01); A61C 5/40 (2017.01); A61C 5/55 (2017.01); A61K 41/00 (2020.01); A61K 9/51 (2006.01); A61K 6/17 (2020.01); A61K 6/52 (2020.01); A61K 6/54 (2020.01); A61K 6/65 (2020.01); A61N 5/06 (2006.01)
CPC A61K 6/62 (2020.01) [A61C 5/40 (2017.02); A61C 5/55 (2017.02); A61K 6/17 (2020.01); A61K 6/52 (2020.01); A61K 6/54 (2020.01); A61K 6/65 (2020.01); A61K 9/5161 (2013.01); A61K 41/0057 (2013.01); A61N 5/062 (2013.01)] 12 Claims
 
1. A method of dental treatment during a root canal treatment of a tooth within an oral cavity of a patient, comprising:
contacting a dentin within the root canal with a therapeutic composition for 15 minutes or less, the therapeutic composition comprising a nonaggregating slurry of functionalized chitosan nanoparticles the contacting allowing the nanoparticles to incorporate into a collagen matrix of the dentin within the root canal, the nanoparticles having a first portion of the nanoparticles comprising deacetylated chitosan covalently bound to photosensitizer moieties and a second portion of the nanoparticles comprising chitosan covalently bound to phosphoryl moieties; and
exposing the nanoparticles incorporated in the collagen matrix of the dentin within the root canal to a light having a wavelength selected to activate the photosensitizer moieties from about 2 minutes to about 10 minutes to (a) crosslink collagen of the collagen matrix within the dentin to the nanoparticles incorporated into the collagen matrix to improve tensile strength and fracture toughness of the dentin and (b) disrupt an existing biofilm in the root canal without cytotoxicity to a patient tissue of the oral cavity.