NOVEL BI-LAYERED PCL/CHITOSAN DOPED WITH ZINC OXIDE SCAFFOLD FOR PERIODONTAL BONE REGENERATION

Abstract

ABSTRACT The loss of periodontal bony support during the progression of periodontal disease results in bone loss around the tooth and eventually loss the tooth structure. Thus, periodontal regeneration is the main aim in the treatment of periodontal bony defects so as to preserve the supporting periodontium and the tooth. Several bone regenerating grafts are available ranging from autografts, xenografts to alloplastic grafts. These grafts are often used with a barrier membrane as regeneration following periodontal regenerative therapy often results in the formation of epithelial and connective tissue attachment rather than the periodontal bony attachment which ultimately defeats the purpose of regenerative therapy. Hence grafts along with barrier membranes that prevent such healing by the formation of long junctional epithelium were developed. But this requires placement of two materials, costing more and requiring more time and efforts out of the clinician. Therefore, layered scaffolds are now taking precedence as they not only help in bone regeneration but also prevent the attachment and regeneration of epithelium at the defect site. Chitosan is a proven regenerative material. The product containing chitosan doped with Zinc oxide was developed which was combined with PCL to act as a barrier. The application of this product was to be used as a scaffold in periodontal intra bony defects due to its excellent osteogenic potential and barrier properties. The innovation of the material is that it’s a bi layered scaffold consisting of a unique combination of PCL/ Chitosan doped with Zinc oxide.

Specification

FORM - 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(see Section 10 & rule 13)

1. TITLE OF THE INVENTION: :
Novel Bi- Layered PCL/ Chitosan eloped with Zinc oxide scaffold for periodontal bone regeneration.

2.APPLICANT:
S.No NAME NATIONALITY ADDRESS
28-Oct-2024/130779/202441082183/Form 2(Title Page)
Saveetha Institute of Medical
and Technical Sciences
INDIAN
No: 162, Poonamallee High
Road, Velappanchavadi,
Chennai-600077

3. PREAMBLE TO THE DESCRIPTION:
The following specification describes the invention and how it is to be performed.

Bank : INDUSIND BANK
Branch : NUNGAMBAKKAM
( SAVEETHA UNIVERSITY )
DD No: 402482
DD Date: 19/10/2024
DD Amount: 8,900/-

TITLE OF THE INVENTION
Novel Bi- Layered PCL/ Chitosan doped with Zinc oxide scaffold for periodontal bone regeneration.

FIELD OF INVENTION
The invention relates to a suitable bi- layered scaffold for periodontal regenerative therapy.

BACKGROUND

Periodontitis is a chronic inflammatory condition characterized by bone loss and loss of the periodontal attachment apparatus resulting from the inflammation mediated by the host.

The main aim of periodontal therapy is to eliminate the cause of this inflammation and restore the periodontium to its normal functional
state. To achieve this, regenerative procedures are performed to restore the lost bone and periodontal support of the tooth/ teeth. These
regenerative procedures are shown to have added benefits in terms of clinical attachment gain and reduction in probing depth when compared to plain flap surgery.

Bone is a dynamic tissue which undergoes constant remodeling. The concept of bone tissue engineering has evolved to involve three basic components- cells, scaffold and growth factors, either alone or in combination with the aim of regenerating the lost bone.

The regeneration procedure that is most often employed is the placement of bone grafts in the defect site. The contemporary bone grafting materials include- allografts, autografts, xenografts and alloplastic materials. These can be used solely or in combination with each other. Whichever the way of application, these bone grafts require a definitive barrier membrane to prevent them from coming in contact with the epithelial and connective tissue surface of gingiva, potentially preventing the healing by formation of the tissues that arise from them. This barrier membrane placement allows selective
regeneration of the periodontal ligament and bone instead of the epithelium. But this entails for the surgeon to properly place the membrane and stabilize it in addition to other considerations like exposure of the membrane and restorability of the membrane, requiring a second stage surgery (in case of non- resorbable membranes).

The regeneration of periodontium requires both regeneration of hard and soft tissues, but these procedures only partially regenerate the
periodontium, they cannot be employed for the complete regeneration of the periodontium.

Foreseeing all the hassles faced during and after placement of such grafts along with a membrane the concept of layered scaffolds was brought into light wherein each layer is designated to perform a specific set of function. All these layers together are meant for complete regeneration of the periodontium.

Chitosan as a biomaterial for bone regeneration has gained much popularity in the field of regenerative periodontics in the last two
decades owing to properties like osteoconductive nature, biocompatibility and bio degradability. It is natural biopolymer derived from crustacean shells and is being used extensively in bone
tissue engineering. Chitosan provides the added advantage of having good porosity, mechanical strength and having a controlled deliverability.

Zinc plays a pivotal role in normal skeletal and bone homeostasis. The deficiency of the same is related to impaired skeletal development and
bone growth in individuals. The standard zinc distribution in the body is 57% in muscle, 29% in bone, 6% in skin, 5% in liver, 1.5% in the
brain, and 0.1% in blood plasma. Cognizant of the effects of zinc on bone metabolism considerable research has established that zinc promotes osteoblastic proliferation, and increases alkaline
phosphatase activity in-vitro and in-vivo. Therefore, the addition of zinc to a scaffold aimed at regenerating bone will help in further
proliferation of the osteoblasts and increase the overall osteogenic potential of the scaffold.

Considering the unique properties of all the three constituents PCL Chitosan doped with Zinc oxide was chosen to develop a layered scaffold for periodontal bone regeneration.

SUMMARYOFTHEINVENTION

The novel scaffold fabricated using chitosan and PCL was either not authenticated or the authentication details were not available in
majority of the studies. The void in literature on bi layered scaffolds for periodontal bone regeneration led to the development of this
product.

In vitro and in vivo studies evaluating PCL and chitosan separately and demonstrating the barrier function and osteogenic potential respectively of these substances and their use in guided tissue
regeneration/ guided bone regeneration stimulated the interest to study both the substances combined together hence combing the properties of both to synthesize a bi- layered scaffold.

Since all the three components are well established with their respective properties, synthesis of this scaffold is economically and
commercially feasible. The anticipated benefit of this scaffold is reduction in the procedural time and fewer complications associated with the post- surgical phase. Furthermore, the use of a single
substance for periodontal regeneration without the intervention of the epithelium will substantially reduce the cost of regeneration procedures and make it feasible to larger extent of the population.

The barrier properties of the scaffold are excellent compared to the commercially available membranes/ scaffold. The osteogenic potential of chitosan and zinc oxide combined with PCL resulted in exceptional hemocompatibility, proliferation, and hydrophobicity of the PCL layer contributing to its barrier function, the product has
outstanding bio- compatibility and stability in biologic environment.

CLAIMS OF THE INVENTION

1. The formulation of the product is from already available Chitosan and PCL and hence economic and feasible.
2. The bi- layered scaffold synthesized using PCL/Chitosan Zinc oxide can be used in periodontal bone regeneration, periodontal bony defects and ridge augmentation procedures.
3. Th product can also be used in socket preservation and around implants in Guided bone regeneration.
4. The product can be used as a barrier in regenerative procedures to prevent epithelial migration.
5. The product can be used in ridge split procedures for augmentation.

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