3D Bioplotter Research Papers
3D printing of multi-scale porous β-tricalcium phosphate scaffolds: Mechanical properties and degradation
Processing-structure-property relationships of 3D-printed multi-scale porous ceramics were investigated. Direct ink writing (DIW) of oil-templated colloidal pastes produced hierarchically porous beta-tricalcium phosphate (TCP) scaffolds. Print architecture and microporosity within filaments were varied, mimicking bone structure. The scaffolds exhibited 60–70 % porosity with interconnected macropores 300–700 μm and microporosity within the filaments at the 10 micron-scale. Varying surfactant and oil concentrations created two micro-pore morphologies – bubble-like pores (emulsion) and channel-like pores (capillary suspension). Emulsion scaffolds were stronger, stiffer and more reliable than capillary suspension scaffolds under both compression and bending. Reducing nozzle diameter and inter-filament distance improved strength and stiffness,…
Switch-on mode of bioenergetic channels regulated by curcumin-loaded 3D composite scaffold to steer bone regeneration
Metabolic energy to steer osteoblastic differentiation of bone marrow mesenchymal stem cells (BMSCs) could be a promising therapeutic target for bone tissue engineering (BTE), but prior knowledge of this issue is limited. To address bone defects with BTE, we customized a three-dimensional (3D)-printed composite scaffold (Cur@MS) to allow the controlled release of curcumin, which could facilitate the “switch-on” mode of Glucose transporter 1 (GLUT1) in BMSCs. Consequently, bioenergetic channels, i.e. glucose uptake, were “switched on” to activate GLUT1-RUNX2 crosstalk, which was closely orchestrated with bone regeneration. Furthermore, curcumin-induced cholesterol/lipid raft (Cho/LR) was a “sensor” to trigger the “switch” (GLUT1) by…
The addition of zinc ions to polymer-ceramic composites accelerated osteogenic differentiation of human mesenchymal stromal cells
Critical-sized bone defects, caused by congenital disorders or trauma, are defects that will not heal spontaneously and require surgical intervention. Recent advances in biomaterial design for the treatment of such defects focus on improving their osteoinductive properties. Here, we propose a bioactive composite with high ceramic content composed of poly(ethyleneoxide terephthalate)/poly(butylene terephthalate) (1000PEOT70PBT30, PolyActive, PA) and 50 % beta-tricalcium phosphate (β-TCP) with the addition of zinc in a form of a coating on the TCP particles. Due to its essential role in bone homeostasis, we hypothesised that the addition of zinc to the polymer-ceramic composite will further enhance its osteogenic…
Enhanced bone regeneration by low-intensity pulsed ultrasound and lipid microbubbles on PLGA/TCP 3D-printed scaffolds
Background To investigate the effect of low-intensity pulsed ultrasound (LIPUS) combined with lipid microbubbles on the proliferation and bone regeneration of bone marrow mesenchymal stem cells (BMSCs) in poly (lactic-glycolic acid copolymer) (PLGA)/α-tricalcium phosphate (TCP) 3D-printed scaffolds. Methods BMSCs were irradiated with different LIPUS parameters and microbubble concentrations, and the best acoustic excitation parameters were selected. The expression of type I collagen and the activity of alkaline phosphatase were detected. Alizarin red staining was used to evaluate the calcium salt production during osteogenic differentiation. Results BMSCs proliferation was the most significant under the condition of 0.5% (v/v) lipid microbubble concentration,…
Crystal Growth of 3D Poly(ε-caprolactone) Based Bone Scaffolds and Its Effects on the Physical Properties and Cellular Interactions
Extrusion additive manufacturing is widely used to fabricate polymer-based 3D bone scaffolds. However, the insight views of crystal growths, scaffold features and eventually cell-scaffold interactions are still unknown. In this work, melt and solvent extrusion additive manufacturing techniques are used to produce scaffolds considering highly analogous printing conditions. Results show that the scaffolds produced by these two techniques present distinct physiochemical properties, with melt-printed scaffolds showing stronger mechanical properties and solvent-printed scaffolds showing rougher surface, higher degradation rate, and faster stress relaxation. These differences are attributed to the two different crystal growth kinetics, temperature-induced crystallization (TIC) and strain-induced crystallization (SIC),…
About the Mechanical Strength of Calcium Phosphate Cement Scaffolds
For the treatment of bone defects, biodegradable, compressive biomaterials are needed as replacements that degrade as the bone regenerates. The problem with existing materials has either been their insufficient mechanical strength or the excessive differences in their elastic modulus, leading to stress shielding and eventual failure. In this study, the compressive strength of CPC ceramics (with a layer thickness of more than 12 layers) was compared with sintered β-TCP ceramics. It was assumed that as the number of layers increased, the mechanical strength of 3D-printed scaffolds would increase toward the value of sintered ceramics. In addition, the influence of the…
Coating of 3D printed PCL/TCP scaffolds using homogenized-fibrillated collagen
Background Poly(3-caprolactone) (PCL)/β-tricalcium phosphate (β-TCP) composite scaffolds fabricated by three-dimensional (3D) printing are one of the common scaffolds for bone tissue regeneration. However, the main challenge of these 3D printed PCL/β-TCP scaffolds is the fact that many cells pass from porosities during in vitro cell seeding, leading to poor initial cell attachment. This study aimed to demonstrate the fabrication of a new collagen coating process for optimizing the hydrophilic property and cell-substrate interactions. This method may be used for coating collagen on any relevant biomedical constructs made of synthetic polymers to increase their biocompatibility and cell attachment. Materials and methods…
3D Bio-Printed Bone Scaffolds Incorporated with Natural Antibacterial Compounds
3D Bioprinting plays an irreplaceable role in bone tissue engineering. Shellac and curcumin are two natural compounds that are widely used in the food and pharmaceutical sectors. In this study, a new composite scaffold with good biocompatibility and antibacterial ability was manufactured by adding shellac and curcumin into the traditional bone scaffold through low-temperature three-dimensional printing (LT-3DP), and its impact on the osteoimmune microenvironment was evaluated.
Development of a modular reinforced bone tissue engineering scaffold with enhanced mechanical properties
A modular design composed of 3D-printed polycaprolactone (PCL) as the load-bearing module, and dual porosity gelatin foam as the bio-reactive module, was developed and characterized in this study. Surface treatment of the PCL module through aminolysis-aldehyde process was found to yield a stronger interface bonding compared to NaOH hydrolysis, and therefore was used in the fabrication procedure. The modular scaffold was shown to significantly improve the mechanical properties of the gelatin foam. Both compressive modulus and ultimate strength was found to increase over 10 times when the modular design was employed. The bio-reactive module i.e., gelatin foam, presented a dual…
Alternative Geometries for 3D Bioprinting of Calcium Phosphate Cement as Bone Substitute
In the literature, many studies have described the 3D printing of ceramic-based scaffolds (e.g., printing with calcium phosphate cement) in the form of linear structures with layer rotations of 90°, although no right angles can be found in the human body. Therefore, this work focuses on the adaptation of biological shapes, including a layer rotation of only 1°. Sample shapes were printed with calcium phosphate cement using a 3D Bioplotter from EnvisionTec. Both straight and wavy spokes were printed in a round structure with 12 layers. Depending on the strand diameter (200 and 250 µm needle inner diameter) and strand…
The evaluation of a multiphasic 3D-bioplotted scaffold seeded with adipose derived stem cells to repair osteochondral defects in a porcine model
There is a need for the development of effective treatments for focal articular cartilage injuries. We previously developed a multiphasic 3D-bioplotted osteochondral scaffold design that can drive site-specific tissue formation when seeded with adipose-derived stem cells (ASC). The objective of this study was to evaluate this scaffold in a large animal model. Osteochondral defects were generated in the trochlear groove of Yucatan minipigs and repaired with scaffolds that either contained or lacked an electrospun tidemark and were either unseeded or seeded with ASC. Implants were monitored via computed tomography (CT) over the course of 4 months of in vivo implantation and…
Three-dimensional printing of clinical scale and personalized calcium phosphate scaffolds for alveolar bone reconstruction
Objective Alveolar bone defects can be highly variable in their morphology and, as the defect size increases, they become more challenging to treat with currently available therapeutics and biomaterials. This investigation sought to devise a protocol for fabricating customized clinical scale and patient-specific, bioceramic scaffolds for reconstruction of large alveolar bone defects. Methods Two types of calcium phosphate (CaP)-based bioceramic scaffolds (alginate/β-TCP and hydroxyapatite/α-TCP, hereafter referred to as hybrid CaP and Osteoink™, respectively) were designed, 3D printed, and their biocompatibility with alveolar bone marrow stem cells and mechanical properties were determined. Following scaffold optimization, a workflow was developed to use…
Three-Dimensional Extrusion Printing of Porous Scaffolds Using Storable Ceramic Inks
In this study, we describe the additive manufacturing of porous three-dimensionally (3D) printed ceramic scaffolds prepared with hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), or the combination of both with an extrusion-based process. The scaffolds were printed using a novel ceramic-based ink with reproducible printability and storability properties. After sintering at 1200°C, the scaffolds were characterized in terms of structure, mechanical properties, and dissolution in aqueous medium. Microcomputed tomography and scanning electron microscopy analyses revealed that the structure of the scaffolds, and more specifically, pore size, porosity, and isotropic dimensions were not significantly affected by the sintering process, resulting in scaffolds that…
Development of bioinks for 3D printing microporous, sintered calcium phosphate scaffolds
Beta-tricalcium phosphate (β-TCP)-based bioinks were developed to support direct-ink 3D printing-based manufacturing of macroporous scaffolds. Binding of the gelatin:β-TCP ink compositions was optimized by adding carboxymethylcellulose (CMC) to maximize the β-TCP content while maintaining printability. Post-sintering, the gelatin:β-TCP:CMC inks resulted in uniform grain size, uniform shrinkage of the printed structure, and included microporosity within the ceramic. The mechanical properties of the inks improved with increasing β-TCP content. The gelatin:β-TCP:CMC ink (25:75 gelatin:β-TCP and 3% CMC) optimized for mechanical strength was used to 3D print several architectures of macroporous scaffolds by varying the print nozzle tip diameter and pore spacing during…
3D porous Ti6Al4V-beta-tricalcium phosphate scaffolds directly fabricated by additive manufacturing
3D Ti6Al4V-beta-tricalcium phosphate (TCP) hybrid scaffolds with interconnected porous network and controllable porosity and pore size were successfully produced by three-dimensional fiber deposition (3DF). The macrostructure of scaffolds was determined by the 3D design, whereas the micro- and submicron structure were derived from the Ti6Al4V powder sintering and the crystalline TCP powder, respectively. Ti6Al4V-TCP slurry was developed for 3DF by optimizing the TCP powder size, Ti6Al4V-to-TCP powder ratio and Ti6Al4V-TCP powder content. Moreover, the air pressure and fiber deposition rate were optimized. A maximum achievable ceramic content in the Ti6Al4V-TCP slurry that enables 3DF manufacturing was 10 wt%. The chemical…
Osteogenic differentiation of adipose-derived mesenchymal stem cells using 3D-Printed PDLLA/ β-TCP nanocomposite scaffolds
Designing bone scaffolds containing both organic and inorganic composites simulating the architecture of the bone is the most important principle in bone tissue engineering. The objective of this study was to fabricate a composite scaffold containing poly (D, l)-lactide (PDLLA) and β-tricalcium phosphate (β-TCP) as a platform for osteogenic differentiation of adipose-derived mesenchymal stem cells. In this study, PDLLA/β-TCP scaffolds were fabricated using three-dimensional printing (3D) technology through melt excursion technique. The physicomechanical characteristics, including microstructure, mechanical properties, of the customized scaffolds were investigated. Further, the in vitro biological characteristics of manufactured scaffolds were evaluated in conjugation with buccal fat…
A tri-component knee plug for the 3rd generation of autologous chondrocyte implantation
Here, we report a newly designed knee plug to be used in the 3rd generation of Autologous Chondrocyte Implantation (ACI) in order to heal the damaged knee cartilage. It is composed of three components: The first component (Bone Portion) is a 3D printed hard scaffold with large pores (~ 850 µm), made by hydroxyapatite and β-tricalcium phosphate to accommodate the bony parts underneath the knee cartilage. It is a cylinder with a diameter of 20 mm and height of 7.5 mm, with a slight dome shape on top. The plug also comprises a Cartilage Portion (component 2) which is a 3D…
Mechanical properties of hybrid triphasic scaffolds for osteochondral tissue engineering
Reproducing the advanced complexity of native tissue by means of the 3D multi-functional construct is a promising tissue engineering approach to osteochondral tissue regeneration. In this study, we present a porous 3D construct composed of three zones responsible for the regeneration of non-calcified cartilage, calcified cartilage and subchondral bone. These three zones of the hybrid were composed of modified biopolymers: (i) alginate (Alg) reinforced by short polylactide (PLA) fibres, (ii) alginate and gelatine methacrylate (GelMA) combined with ß-tricalcium phosphate particles (TCP), (iii) 3D printed polycaprolactone scaffold subsequently modified with the use of an innovative solvent treatment method based on acetone…
Incorporation of functionalized reduced graphene oxide/magnesium nanohybrid to enhance the osteoinductivity capability of 3D printed calcium phosphate-based scaffolds
Improving bone regeneration is one of the most pressing problems facing bone tissue engineering (BTE) which can be tackled by incorporating different biomaterials into the fabrication of the scaffolds. The present study aims to apply the 3D-printing and freeze-drying methods to design an ideal scaffold for improving the osteogenic capacity of Dental pulp stem cells (DPSCs). To achieve this purpose, hybrid constructs consisted of 3D-printed Beta-tricalcium phosphate (β-TCP)-based scaffolds filled with freeze-dried gelatin/reduced graphene oxide-Magnesium-Arginine (GRMA) matrix were fabricated through a novel green method. The effect of different concentrations of Reduced graphene oxide-Magnesium-Arginine (RMA) (0, 0.25% and 0.75%wt) on the…
Multimaterial Dual Gradient Three-Dimensional Printing for Osteogenic Differentiation and Spatial Segregation
In this study of three-dimensional (3D) printed composite β-tricalcium phosphate (β-TCP)-/hydroxyapatite/poly(ɛ-caprolactone)-based constructs, the effects of vertical compositional ceramic gradients and architectural porosity gradients on the osteogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (MSCs) were investigated. Specifically, three different concentrations of β-TCP (0, 10, and 20 wt%) and three different porosities (33% ± 4%, 50% ± 4%, and 65% ± 3%) were examined to elucidate the contributions of chemical and physical gradients on the biochemical behavior of MSCs and the mineralized matrix production within a 3D culture system. By delaminating the constructs at the gradient transition point, the spatial separation of cellular phenotypes could be specifically…
Three-dimensional printed multiphasic scaffolds with stratified cell-laden gelatin methacrylate hydrogels for biomimetic tendon-to-bone interface engineering
Background The anatomical properties of the enthesis of the rotator cuff are hardly regained during the process of healing. The tendon-to-bone interface is normally replaced by fibrovascular tissue instead of interposition fibrocartilage, which impairs biomechanics in the shoulder and causes dysfunction. Tissue engineering offers a promising strategy to regenerate a biomimetic interface. Here, we report heterogeneous tendon-to-bone interface engineering based on a 3D-printed multiphasic scaffold. Methods A multiphasic poly(ε-caprolactone) (PCL)–PCL/tricalcium phosphate–PCL/tricalcium phosphate porous scaffold was manufactured using 3D printing technology. The three phases of the scaffold were designed to mimic the graded tissue regions in the tendon-to-bone interface—tendon, fibrocartilage, and…
Investigation of multiphasic 3D-bioplotted scaffolds for sitespecific chondrogenic and osteogenic differentiation of human adipose-derived stem cells for osteochondral tissue engineering applications
Osteoarthritis is a degenerative joint disease that limits mobility of the affected joint due to the degradation of articular cartilage and subchondral bone. The limited regenerative capacity of cartilage presents significant challenges when attempting to repair or reverse the effects of cartilage degradation. Tissue engineered medical products are a promising alternative to treat osteochondral degeneration due to their potential to integrate into the patient’s existing tissue. The goal of this study was to create a scaffold that would induce site‐specific osteogenic and chondrogenic differentiation of human adipose‐derived stem cells (hASC) to generate a full osteochondral implant. Scaffolds were fabricated using…
3D printing of silk fibroin-based hybrid scaffold treated with platelet rich plasma for bone tissue engineering
3D printing/bioprinting are promising techniques to fabricate scaffolds with well controlled and patient-specific structures and architectures for bone tissue engineering. In this study, we developed a composite bioink consisting of silk fibroin (SF), gelatin (GEL), hyaluronic acid (HA), and tricalcium phosphate (TCP) and 3D bioprinted the silk fibroin-based hybrid scaffolds. The 3D bioprinted scaffolds with dual crosslinking were further treated with human platelet-rich plasma (PRP) to generate PRP coated scaffolds. Live/Dead and MTT assays demonstrated that PRP treatment could obviously promote the cell growth and proliferation of human adipose derived mesenchymal stem cells (HADMSC). In addition, the treatment of PRP…
Design of a new 3D‐printed joint plug
This paper introduces a kit of parts as a novel three‐dimensional (3D)–printed joint plug, in which each of the parts function cooperatively to treat cartilage damage in joints of the human body (e.g., hips, wrists, elbow, knee, and ankle). Three required and one optional parts are involved in this plug. The first part is a 3D‐printed hard scaffold (bone portion) to accommodate bone cells, and the second is a 3D‐printed soft scaffold (cartilage portion) overlying the bone portion to accommodate chondrocytes. The third part of joint plug is a permeable membrane, termed film, to cover the entire plug to provide…
3D printed β-TCP scaffold with sphingosine 1-phosphate coating promotes osteogenesis and inhibits inflammation
Traditional treatments for bone repair with allografts and autografts are limited by the source of bone substitutes. Bone tissue engineering via a cell-based bone tissue scaffold is a new strategy for treatment against large bone defects with many advantages, such as the accessibility of biomaterials, good biocompatibility and osteoconductivity; however, the inflammatory immune response is still an issue that impacts osteogenesis. Sphingosine 1-phosphate (S1P) is a cell-derived sphingolipid that can mediate cell proliferation, immunoregulation and bone regeneration. We hypothesised that coating S1P on a β-Tricalcium phosphate (β-TCP) scaffold could regulate the immune response and increase osteogenesis. We tested the immunoregulation…
Multimaterial Segmented Fiber Printing for Gradient Tissue Engineering
In this work, we present a printing method to fabricate scaffolds consisting of multimaterial segmented fibers. Particularly, we developed a reproducible printing process to create single fibers with multiple discrete compositions and control over the distribution of particulate ceramics—namely hydroxyapatite (HA) and β-tricalcium phosphate (TCP)—within poly(ɛ-caprolactone)-based composite scaffolds. Tensile testing revealed that the mechanical integrity of individual segmented fibers was preserved compared with nonsegmented fibers, and microcomputed tomography and thermal analysis confirmed the homogeneous distribution of ceramics incorporated in the fiber compositions. Moreover, we printed and characterized composite scaffolds containing model inverse radial gradients of HA and TCP that could…
Three-dimensional printing of β-tricalcium phosphate/calcium silicate composite scaffolds for bone tissue engineering
Bioactive scaffolds with interconnected porous structures are essential for guiding cell growth and new bone formation. In this work, we successfully fabricated three-dimensional (3D) porous β-tricalcium phosphate (β-TCP)/calcium silicate (CS) composite scaffolds with different ratios by 3D printing technique and further investigated the physiochemical properties, in vitro apatite mineralization properties and degradability of porous β-TCP/CS scaffolds. Moreover, a series of in vitro cell experiments including the attachment, proliferation and osteogenic differentiation of mouse bone marrow stromal cells were conducted to testify their biological performances. The results showed that 3D printed β-TCP/CS scaffolds possessed of controllable internal porous structures and external…
3D-printed IFN-γ-loading calcium silicate-β-tricalcium phosphate scaffold sequentially activates M1 and M2 polarization of macrophages to promote vascularization of tissue engineering bone
To promote vascularization of tissue-engineered bone, IFN-γ polarizing macrophages to M1 was loaded on 5% calcium silicate/β-tricalcium phosphate (CaSiO3-β-TCP) scaffolds. IFN-γ and Si released from the scaffold were designed to polarize M1 and M2 macrophages, respectively. β-TCP, CaSiO3-β-TCP, and IFN-γ@CaSiO3-β-TCP were fabricated and biocompatibilities were evaluated. Polarizations of macrophages were detected by flow cytometry. Human umbilical vein endothelial cells with GFP were cultured and induced on Matrigel with conditioned culture medium extracted from culture of macrophages loaded on scaffolds for evaluating angiogenesis. Four weeks after the scaffolds were subcutaneously implanted into C57B1/6, vascularization was evaluated by visual observation, hematoxylin and…
3D Bio-Plotted Tricalcium Phosphate/Zirconia Composite Scaffolds to Heal Large Size Bone Defects
β-TCP-Zirconia scaffolds with different architectures were fabricated by means of 3D-Bioplotting in order to enhance the mechanical and in-vitro ability of the scaffold to heal large size bone defects. In the present study scaffold architecture with different strand orientations (0o-90o, 0o-45o-135o-180o, 0o-108o-216o and 0o-72o-144o-36o-108o) were fabricated, characterized and evaluated for mechanical strength and cell proliferation ability. β-TCP powder (25µm) and PVA (Polyvinyl Alcohol) was acquired from Fisher Scientific, India. Zirconia (18 to 32 µm) was procured from Lobachemie, India. In brief 7.5%, PVA in distilled water was used as a binder and was mixed with 10 grams of (70/30) TCP-Zirconia…
The preliminary performance study of the 3D printing of a tricalcium phosphate scaffold for the loading of sustained release anti-tuberculosis drugs
In the surgical treatment of tuberculosis of the bones, excision of the lesion site leaves defects in the bone structure. Recent research has shown benefits for bone tissue support, such as tricalcium phosphate, as regrowth materials. These biocompatible engineering materials have good bone inductivity and biologic mechanical performance. The goal of this study was to evaluate the use of 3D printing, a new technology, to design and build 3-dimensional support structures for use in grafting at lesion sites and for use in embedding the sustained release anti-tuberculosis drugs Rifampin and Isoniazid and determine the in vivo performance of these structures.…
Comparison of bacterial adhesion and cellular proliferation on newly developed three-dimensional scaffolds manufactured by rapid prototyping technology
Scaffolds used in the field of tissue engineering should facilitate the adherence, spreading, and ingrowth of cells as well as prevent microbial adherence. For the first time, this study simultaneously deals with microbial and tissue cell adhesion to rapid prototyping-produced 3D-scaffolds. The cell growth of human osteosarcoma cells (CAL-72) over a time period of 3-11 days were examined on three scaffolds (PLGA, PLLA, PLLA-TCP) and compared to the adhesion of salivary microorganisms and representative germs of the oral flora (Porphyromonas gingivalis, Prevotella nigrescens, Candida albicans, Enterococcus faecalis, Streptococcus mutans, and Streptococcus sanguinis). Scanning electron microscopy (SEM), cell proliferation measurements, and…
Bone repair by cell-seeded 3D-bioplotted composite scaffolds made of collagen treated tricalciumphosphate or tricalciumphosphate-chitosan-collagen hydrogel or PLGA in ovine critical-sized calvarial defects
The aim of this study was to investigate the osteogenic effect of three different cell-seeded 3D-bioplotted scaffolds in a ovine calvarial critical-size defect model. The choice of scaffold-materials was based on their applicability for 3D-bioplotting and respective possibility to produce tailor-made scaffolds for the use in cranio-facial surgery for the replacement of complex shaped boneparts. Scaffold raw-materials are known to be osteoinductive when being cell-seeded [poly(L-lactide-co-glycolide) (PLGA)] or having components with osteoinductive properties as tricalciumphosphate (TCP) or collagen (Col) or chitosan. The scaffold-materials PLGA, TCP/Col, and HYDR (TCP/Col/chitosan) were cell-seeded with osteoblast-like cells whether gained from bone (OLB) or from…
Bacterial and Candida albicans adhesion on rapid prototyping-produced 3D-scaffolds manufactured as bone replacement materials
Rapid prototyping (RP)-produced scaffolds aregaining increasing importance in scaffold-guided tissueengineering. Microbial adhesion on the surface of replacement materials has a strong influence on healing and long-term outcome. Consequently, it is important to examine the adherence of microorganisms on RP-produced scaffolds. This research focussed on manufacturing of scaffolds by 3D-bioplotting and examination of their microbial adhesion characteristics. Tricalciumphosphate (TCP), calcium/sodium alginate, and poly(lactide-co-glycolic acid) (PLGA) constructs were produced and used to study the adhesion of dental pathogens. Six oral bacterial strains, one Candida strain and human saliva were used for the adhesion studies. The number of colony forming units (CFU) were…