Medical implants have emerged as indispensable tools in modern healthcare, which offers innovative solutions for a diverse array of medical conditions and improve patient outcomes. The phrase "medical implant" embraces a wide range of devices that are surgically inserted within the body to replace, support, or augment organic structures or functions¹. These devices are carefully crafted within the body tissues to blend in an effortless manner, guaranteeing maximum compatibility and functionality. Medical implants have developed over time due to discoveries in materials science, manufacturing processes, and surgical methods, which have made it possible to achieve previously unheard-of levels of precision, durability, and therapeutic efficacy². They are known for their adaptability, which allows them to be used for a broad range of clinical applications and medical specializations such as orthopedic implants for spinal and joint replacements, dental implants, cardiac implants like pacemakers and defibrillators or neural implants etc.³ They play an important role in restoring function, relieving symptoms, and improving the quality of life for millions of patients worldwide⁴. To design the medical implants includes careful selection of materials includes biocompatibility, mechanical strength, and corrosion resistance⁵. Titanium and its alloys, cobalt-chrome, and biocompatible polymers are the most commonly used materials in implant construction due to their ability to withstand physiological stressors with the least degree of negative body reaction^6-8.

Furthermore, innovations in implant design and manufacturing have permitted the fabrication of patient-specific implants that are fitted to each patient's unique anatomical variations in order to improve surgical outcomes and reduce problems⁷. Apart from technological advancements, the widespread use of minimally invasive surgical approaches has altered the implantation procedure, allowing patients to heal faster, with less trauma and smaller incisions⁸.

The potential for implanted devices grows as medical knowledge advances. Emerging technology, such as smart implants equipped with sensing capacities and therapeutic functionalities, pave the way for individualized and proactive healthcare interventions⁹. Furthermore, there is a chance to create bioengineered implants that can blend in with the body and encourage tissue regeneration thanks to continuing research in tissue engineering and regenerative medicine^10,11. Medical implants represent a cornerstone of modern medicine, offering patients a lifeline to improved health, function, and well-being¹. The field of implanted devices continues to push the frontier of what is possible via innovation, teamwork, and a commitment to patient-centered care, ushering in a new era of tailored and innovative healthcare¹².

1. FDA Classification of Medical Devices:

The Food and Drug Administration (FDA) in the US controls the use of medical implants. An implant may only be used if it is intended for the diagnosis, treatment, or prevention of disease in humans or animals and has been registered in the United States Pharmacopoeia or National Formulary. The most important need, however, is that the medical implant affects the body's structure or function rather than relying merely on chemical action as is the case with drugs to achieve its goals¹³. Medical devices are categorized by the US-FDA into three classes according to the degree of control required to ensure the device's efficacy and safety. Title 21 of the Code of Federal Regulations (CFR) Part 800-1299, which contains the FDA's implementing regulations, and the Federal Food, Drug, and Cosmetic Act define these classes¹⁴. The FDA classifications are as follows and summarized in Table 1.

2.1 Class I Medical Devices: These devices are low-risk considered as least regulatory control. They are simple in design and has very less potential harm to the user. The general regulations required to apply for these devices include correct FDA notification, registration, manufacturing, branding, and labeling. Class 1 devices mostly used in orthopedics includes tongue depressors, examination gloves, arthroscope and elastic bandages. They do not require any type of specific scientific evaluation unless they are intended for a specific purpose or pose higher risks^15,16.

2.2 Class II Medical Devices: These devices require some restrictions and controls as they pose a moderate to high risk to user safety and efficacy. They can be used to support or sustain human life, prevent health impairment, or offer a possible risk of disease or harm. They are more complex than Class I devices. It is necessary to implement special controls that include labeling specifications, performance benchmarks, and sufficient surveillance on this class devices. Some examples of Class II devices include powered wheelchairs, infusion pumps, imaging devices such as X-ray machines, PACS, Fluoroscopes and surgical drapes, surgical needles, sutures etc. They do not require any scientific evaluation^13,16.

2.3 Class III Medical Devices: These devices are subject to the highest level of regulatory control and considered as high-risk. Class III devices generally require premarket approval (PMA) from the FDA, which involves comprehensive scientific and clinical data to demonstrate safety and effectiveness. They are typically life-supporting or life-sustaining devices, are implanted into the body, or pose significant risks to health. This is the most rigorous and scientific classification of medical devices. Some examples of Class III devices include implantable pacemakers, heart valves, and silicone breast implants etc.^13,16.

2. Types of Implants:

Medical implants are a broad category of devices intended to supplement, replace, or support biological structures or bodily processes. These implants meet a range of clinical needs and are useful for different medical specializations¹. The following are a common type of medical implants and materials used in different types of implants are summarized in Table 2.

3.1 Orthopedic implants:

These devices used in orthopedic surgery to replace or stabilize damaged or diseased bones, joints, or other skeletal structures. They are meant to improve patients' quality of life, alleviate discomfort, and restore function in musculoskeletal problems. Here are some common types of orthopedic implants.

3.1.1 Joint Replacements:

These implants are used to repair injured joints, including elbows, hips, ankels, knees, and shoulders. Typically, they are constructed with a mixture of ceramic, plastic, and metal components. Some examples of replacements include total hip replacements, total knee replacements, and shoulder arthroplasties^18,19.

3.1.2 Spinal implants:

They are used to stabilize and support the spine in cases of spinal deformities, degenerative disc disease, or spinal trauma. They consist of artificial discs and spinal fusion devices such rods, screws, plates, and cages. Usually composed of metals like titanium or alloys and may incorporate biocompatible polymers^18-20.

3.1.3 Ortho biologics:

They are biological materials used to augment or facilitate bone healing. They include bone grafts, bone morphogenetic proteins (BMPs), demineralized bone matrix (DBM), and platelet-rich plasma (PRP). They are used in conjunction with implants to enhance bone fusion and promote tissue regeneration¹⁹.

3.1.4 Fracture fixation devices: These implants are meant to aid in the stabilization and healing of broken bones. They include plates, screws, rods, and pins made of metals like stainless steel, titanium, or cobalt-chromium alloys. Some orthopedic procedures where fracture fixation devices are used such as open reduction internal fixation (ORIF) of long bone fractures^18,19.

3.1.5 Orthopedic prosthetics: These implants are used to replace missing or amputated limbs or joints. They consist of prosthetic joints, like knee or ankle prostheses, as well as prosthetic limbs, like artificial arms or legs. These implants are made to order to match the individual patient's anatomy and restore function and mobility²⁰.

3.1.6 Orthopedic Trauma Implants: These implants are used to treat traumatic musculoskeletal injuries, including soft tissue injuries, fractures, and dislocations. Some examples of these implants include specialized plates, screws, nails, and external fixation devices designed to provide stability and support during the healing process^19,20.

3.2 Dental Implants:They are used to replace lost teeth and improve oral health and appearance. They are surgically implanted into the jawbone and are designed to mimic the anatomy and function of natural teeth. They provide improved stability, durability, and functionality, enabling patients to chew, speak, and smile with confidently²¹. Here are some common types of dental implants:

3.2.1 Implant Fixture: The implant fixture is a small titanium post that is surgically implanted into the jawbone. It serves as an artificial root for the tooth, giving the dental prosthetic stability and support. This device is biocompatible and fuses with the surrounding bone using a process known as osseointegration ²¹.

3.2.2 Dental Prosthesis: It is the visible part of the dental implant that resembles a natural tooth or teeth. It can be a denture that replaces some or all of the teeth in a dental arch, a single crown, or a bridge that spans numerous teeth. The dental prosthesis is made to order to precisely match the patient's original teeth in terms of size, color, and shape for optimal aesthetics and function ^{22, 23}.

3.2.3 Dental Prosthesis: It is the visible part of the dental implant that resembles a natural tooth or teeth. It can be a denture that replaces some or all of the teeth in a dental arch, a single crown, or a bridge that spans numerous teeth. The dental prosthesis is made to order to precisely match the patient's original teeth in terms of size, color, and shape for optimal aesthetics and function ^{22, 23}.

3.2.4 Abutment: It is a connecting element that fix to the implant fixture and protrudes above the gum line. It acts as a framework for the dental prosthesis, such as a denture, bridge, or crown. They are usually made of titanium, zirconia, or other biocompatible materials^21,22.

3.3 Cardiac Implants:

These implants are used to treat various heart conditions and disorders by regulating heart rhythm, supporting cardiac function, or managing cardiovascular diseases. They are intended to improve patients' overall quality of life, avoid potentially fatal arrhythmias, and restore normal cardiac function ²⁴. Here are some common types of cardiac implants:

3.3.1 Implantable Cardioverter- Defibrillators (ICDs): ICDs are sophisticated cardiac devices that monitor cardiac rhythm and administer therapeutic measures, such as pacing or shocks, to restore normal cardiac rhythm in case of dangerous arrhythmias or sudden cardiac arrest. ICDs are designed to detect and treat potentially fatal arrhythmias such ventricular tachycardia or ventricular fibrillation. They are implanted into the heart and come with sensing electrodes and defibrillation leads^24,25.

3.3.2 Pacemakers: These devices are used to regulate the heart's electrical activity and maintain a normal heart rate. They are made up of a one or more leads (wires) and pulse generator that are inserted into the heart muscle. Pacemakers provide electrical impulses to the heart to stimulate contractions when the heart’s natural pacemaker, the sinoatrial node, fails to do so properly. They are used to treat bradycardia and certain types of heart’s blockage²⁴.

3.3.3 Cardiac Resynchronization Therapy (CRT) Pacemakers: CRT pacemakers, are used to improve the coordination and efficiency of heart contractions in patients with heart failure and conduction problems. These gadgets optimize cardiac performance and lessen heart failure symptoms like exhaustion and dyspnea by delivering synchronized electrical impulses to the the heart chambers. Components of CRT devices include a pacemaker generator and leads implanted into the right atrium, right ventricle, and left ventricle of the heart^24-26.

3.3.4 Left Ventricular Assist Devices (LVADs): LVADs are mechanical pumps that are implanted into the heart to sustain circulation and increase cardiac output in patients with advanced heart failure. LVADs are generally used as destination therapy for patients deemed ineligible for heart transplantation, or as a bridge to heart transplantation. Patients with severe heart failure can experience improved symptoms and quality of life because to these surgically implanted devices that help the weaker left ventricle pump blood to the body^24-26.

3.3.5 Implantable Loop Recorders (ILRs): ILRs are used to continuously monitor a patient's cardiac rhythm in cases of suspected arrhythmias or unexplained syncope (fainting). ILRs capture and retain electrocardiogram (ECG) data continuously, enabling doctors to diagnose arrhythmias and examine cardiac rhythm trends over time. ILRs are especially helpful in detecting asymptomatic or intermittent arrhythmias that may not be captured by conventional ECG monitoring methods^24-26.

3.4 Neural Implants:

Neural implants, or brain implants or neuroprosthetics, work with the neural system to treat neurological diseases, enhance cognitive ability, or restore lost sensory or motor function. By electrically stimulating neurons or by monitoring neural activity, these implants establish a direct connection with neural tissue^27-28. Here are some common types of neural implants:

3.4.1 Retinal Implants: These implants, also called as visual prostheses, are used to restore eyesight in individuals with severe vision loss or blindness due to retinal degenerative disorders such as retinitis pigmentosa or age-related macular degeneration. These devices are made up of a variety of microelectrodes that are inserted into the retina. When these electrodes are stimulated by visual stimuli, the remaining retinal ganglion cells respond, allowing vision to be perceived ^27,28.

3.4.2 Cochlear Implants: These implants are also called as Neural prosthesis are used to help people who are deaf or have severe to profound hearing loss hear again. These implants are made up of an internal electrode array that is surgically placed into the cochlea and an external microphone and speech processor that record and process sound data. By stimulating the auditory nerve fibers instead of the injured inner ear hair cells, the electrode array enables the brain to sense sound^27,28.

3.4.3 Neurostimulators for Pain Management: Neurostimulation implants are used to manage Chronic pain disorders such as neuropathic pain, pain associated with spinal cord injuries, and failed back surgery syndrome. By regulating pain signals and delivering electrical impulses to the spinal cord or peripheral nerves, these implants reduce pain. These implants used for pain management include peripheral nerve stimulators (PNS) and spinal cord stimulators (SCS)^27,28.

3.4.4 Deep Brain Stimulation (DBS) Implants: DBS implants are used to treat a variety of mental conditions, including treatment-resistant depression and obsessive-compulsive disorder (OCD), as well as movement disorders like dystonia, essential tremor, and Parkinson's disease. Through surgically inserted electrodes, these implants distribute electrical impulses to precise brain locations, regulating aberrant neural activity and reducing symptoms^27,28.

3.4.5 Brain-Computer Interfaces (BCIs): BCIs enable direct connection between the brain and external devices, allowing individuals to control computers, prosthetic limbs, or other assistive technologies using their thoughts. With implanted electrodes, brain activity is normally recorded by BCIs, which then decode the signals to provide orders for external devices. BCIs have the potential to help people with severe motor disorders regain their ability to communicate and move about^27,28.

3.4.6 Neuroprosthetic Limbs: They are also called as brain-controlled prosthetics or bionic limbs, are devices that help people with limb loss or deficit regain function in their limbs. These implants communicate with the motor cortex or peripheral nervous system to interpret brain signals pertaining to the goal of movement and regulate artificial or robotic limbs. The goal of neuroprosthetic limbs is to improve amputees' mobility and independence by restoring naturalistic and intuitive limb movements^27,28.

3.5 Breast implants:

These implants are used for breast reconstruction after a mastectomy, which involves the surgical removal of one or both breasts, or breast augmentation, which is cosmetic breast enlargement. Usually, these implants consist of an exterior silicone shell filled with silicone gel (silicone implants) or saline solution (saline implants)^29,30.

3.6 Ocular Implants:

Ocular implants, also known as intraocular implants, are used to cure a variety of eye diseases and disorders, improve ocular function, or restore eyesight. These implants are intended to replace or enhance particular components within the eye, and they are usually placed into the eye surgically^31,32. Here are some common types of ocular implants:

3.6.1 Keratoprostheses: Keratoprostheses are also called artificial corneas, when traditional corneal transplantation is neither practical or successful, injured or opaque corneas are replaced with artificial corneas. Biocompatible materials like polymethyl methacrylate (PMMA) or synthetic hydrogels are commonly used to create keratoprostheses. To enhance visual function and restore clarity, they are implanted into the corneal tissue ^31,32.

3.6.2 Glaucoma Drainage Implants: These implants, also called aqueous shunts, are used to lower intraocular pressure (IOP) in patients with glaucoma by facilitating the drainage of aqueous humor from the eye. These implants entail the insertion of a tiny tube or shunt into the anterior chamber of the eye to redirect extra fluid to a reservoir or drainage site. The tube or shunt is composed of biocompatible materials like silicone or polyethylene ^31,32.

3.6.3 Intraocular Lenses (IOLs): These implants are used in cataract surgery to replace the natural lens of the eye or to treat refractive defects such astigmatism, myopia, and hyperopia. Typically, biocompatible materials like silicone or acrylic are used to make IOLs. To meet diverse needs for vision correction, they can be designed in a variety of ways and be either stiff or flexible^31,32.

3.6.4 Corneal Implants: Corneal implants, such as corneal inlays or rings, are used to treat Corneal irregularities like keratoconus or corneal ectasia, to rectify refractive defects in the cornea. They are placed into the corneal stroma to strengthen or restructure the cornea and enhance visual acuity. They can be composed of biocompatible synthetic materials like hydrogel or polymethylmethacrylate (PMMA) ^{31, 32}.

3.7 Vascular Implants:

These implants are used to treat various vascular disorders or conditions involving blood vessels (arteries, or veins). These implants are intended to repair damaged or weakening vessels, restore blood flow, or avoid problems from vascular diseases ^33-34. Here are some common types of vascular implants:

3.7.1 Stents: Stents are tubular devices that help increase blood flow by supporting weak or constricted blood arteries. Peripheral artery disease, coronary artery disease, and other vascular disorders are frequently treated with them. Stents come in two varieties: drug-eluting and bare metal. Drug-eluting stents release pharmaceuticals (such as anti-inflammatory or anti-proliferative agents) to prevent restenosis (re-narrowing) of the treated artery, whereas bare-metal stents sustain the arterial wall structurally ^33-34.

3.7.2 Vascular Grafts: These are synthetic or biological conduits used to repair or bypass damaged blood vessels. They are frequently used in vascular surgery to repair aneurysms, restore blood flow in cases of vascular damage, or blockage of an artery. Vascular grafts fall into two categories: biological (derived from human or animal tissues) and synthetic (made up of polymers). They can be utilized as bypass grafts for peripheral bypass surgery, coronary artery bypass surgery, or hemodialysis vascular access³⁵.

3.8 Cosmetic Implants:

These implants are used to reconstruct or enhance the appearance, symmetry, or proportion of certain body parts. These implants can be utilized for reconstructive or cosmetic procedures, and they are made to enhance or remodel particular anatomical traits ³⁶. Here are some common types of cosmetic implants:

3.8.1 Facial Implants: Facial implants are used to augment or improve chin, cheekbones, and jawline are just a few of the facial characteristics. They can repair congenital defects, restore volume lost due to aging, and improve facial symmetry. Mandibular angle or body implants are examples of facial implants, as are cheek implants (malar or submalar), chin implants (mentoplasty), and jaw implants. Usually constructed of solid silicone or other biocompatible materials, these implants are tailored to the specific facial architecture of each patient^36,37.

3.8.2 Buttock Implants: Buttock implants also called as gluteal implants, are used to enhance the size and shape of the buttocks. To give the buttock area a more rounded or elevated appearance, they provide volume and projection. Usually constructed of solid silicone, buttock implants are surgically inserted into the subcutaneous tissue or gluteal muscles. To obtain the appropriate aesthetic result, they are available in a variety of sizes and shapes^36-38.

3.8.3 Calf Implants: Calf implants are used to augment the size and definition of the calves for individuals with underdeveloped or asymmetrical calf muscles. They give the lower leg more defined and contoured muscles. Typically composed of solid silicone, calf implants are inserted through tiny incisions made behind the knees behind the calf muscle tissue. They come in various sizes and shapes to fit the patient's natural body^36-38.

3.8.4 Penile Implants: Penile implants, also called penile prostheses, are used to treat men with erectile dysfunction (impotence) who have not responded to conventional treatments like medication or vacuum erection devices. They give erections that are strong enough for sexual activity both hardness and support. Penile implants come in malleable or inflatable varieties. Whereas malleable implants are made of flexible rods surgically positioned along the length of the penis, inflatable implants are made of inflatable cylinders inserted within the penis^36-38.

Table: 2 Materials commonly used in different types of medical implants

Types of Implants	Metals	Polymers	Ceramics	Examples	Refrences
Orthopedic Implants	Titanium alloys (e.g., Ti-6Al-4V), stainless steel, cobalt-chromium alloys	UHMWPE	Alumina, zirconia and calcium phosphate ceramics (hydroxyapatite, tricalcium phosphate)	Joint replacements (e.g., hip, knee), Plates, screws, and rods for fracture fixation, Spinal implants	[39, 40]
Dental Implants	Titanium and titanium alloys (e.g., Ti-6Al-4V), Stainless Steel	PEEK, PMMA, PTFE, PVC	Alumina, zirconia, glass ceramics	crowns, bridges, dentures	[39, 41, 42]
Cardiac Implants	Titanium alloys, Stainless Steel, Cobalt-Chromium Alloys	PU, silicone elastomers, PET, PTFE	Alumina, zirconia	Pacemakers, Cardiac stents	[39, 43, 44]
Neural Implants	Platinum, iridium, Titanium and Titanium Alloys, Stainless Steel	Silicone elastomers, polyimides, PEG, PTFE	Alumina, silicon nitride, Glass for insulation in neural probes	Cochlear implants, Retinal implants	[39, 45]
Breast Implants	Titanium and Titanium Alloys, Stainless Steel, Platinum-Cured Silicone	Silicone elastomers, PU foam, hydrogel	N/A	Silicone or saline-filled implants for breast reconstruction or augmentation	[46, 47]
Ocular Implants	Titanium and Titanium Alloys, Stainless Steel, Platinum, Iridium	Silicone elastomers, PMMA, hydrogel, PTFE	Alumina, zirconia	Intraocular lenses (IOLs), Glaucoma drainage implants,	[39, 48]
Vascular Implants	Titanium and Titanium Alloys, Stainless Steel, Cobalt-Chromium Alloys	PU, PET, PTFE, expanded PTFE	N/A	Stents, Vascular grafts,	[39, 49]
Cosmetic Implants	Titanium and Titanium Alloys, Stainless Steel, Platinum-Cured Silicone	Solid silicone, silicone elastomers, PU foam, hydrogel	N/A	Facial implants (e.g., chin, cheek, jaw), Buttock implants, Calf implants, Penile implants	[36, 39]

Abbrevation: PU: Polyurethane; PMMA: Polymethyl methacrylate; PTFE: Polytetrafluoroethylene; PEG: Polyethylene Glycol; PET: Polyethylene terephthalate; PEEK: Polyetheretherketone; PVC: Polyvinyl chloride; UHMWPE: Ultra-high molecular weight polyethylene

3. Future trends and innovation of medical implants:

Emerging trends in materials science, bioengineering, and healthcare delivery, along with technological improvements, are expected to produce major advancements in medical implants in the future. There are some expected developments and trends in the field of medical implants in the future are as follows:

4.1 Biodegradable Implants: The development of biodegradable implants is a viable way to overcome the drawbacks of permanent implants, including the possibility of long-term issues and the requirement for surgical removal. Biodegradable implants have the ability to break down over time, progressively blending in with the surrounding tissues and removing the need for follow-up procedures⁵⁰.

4.2 3D Printing and Additive Manufacturing: With the use of 3D printing technologies, implants with intricate geometries and unique features can be made for each patient. This method enables quick prototyping, customized implant designs based on the anatomy of each patient, and the integration of medication delivery systems or bioactive materials right into the implant's structure⁵¹.

4.3 Smart Implants and Biosensors: Medical implants with integrated sensors and wireless communication capabilities allow for remote patient monitoring, biomarker identification, and real-time physiological parameter monitoring. Because they offer actionable data into a patient's health status, smart implants have the potential to transform the management of disease, aid in early diagnosis, and enhance patient outcomes^52,53.

4.4 Nanotechnology: Nanomaterials show significant promise as materials for future medical implants due to their unique properties such as increased biocompatibility, the ability to deliver medications, and the possibility for tissue regeneration. Implants with nanotechnology capabilities can reduce the risk of infection, limit inflammation, and accelerate healing, improving patient outcomes and minimizing medical expenses⁵⁴.

4.5 Regenerative Medicine and Tissue Engineering: Tissue engineering and regenerative medicine are making progress toward developing bioengineered implants that may heal or regenerate damaged organs and tissues rather than simply replacing or supporting them. Potential solutions for tissue regeneration, wound healing, and organ transplantation are provided by biomimetic scaffolds, stem cell therapies, and tissue-engineered constructions^55,56.

4.6 Implantable Microdevices and Bioelectronics: Bioelectronic implants and implantable microdevices have the potential to revolutionize neuromodulation therapy, medicines, and diagnostics. Patients with neurological traumas or disorder, these devices can stimulate brain circuits, interact with the nervous system, and restore lost motor or sensory function^57,58.

4.7 Remote Monitoring and Telemedicine Integration:

The integration of medical implants with remote monitoring platforms and telemedicine systems enables improved patient care and reductions in healthcare inequities, particularly among those with limited resources. This enables healthcare personnel to remotely monitor patient health status, alter therapy parameters, and offer timely interventions^59,60.

4.8 Bioresorbable Electronics: Bioresorbable electronics are a novel solution to implantable medical devices that can break down naturally within the body over time, eliminating the need for invasive treatments. These devices allow for transitory sensing, diagnostic, and therapeutic interventions in areas like drug delivery, wound healing, and neurological interfaces⁶¹.

4.9 Personalized Medicine and Genomic Implants: Advancements in genomic medicine and personalized healthcare are accelerating the development of genetically modified implants that are tailored to each patient's distinct genetics, immunological sensitivities, and metabolic profile. Precision medicine approaches may boost treatment efficacy, reduce side effects, and improve patient outcomes^62,63.

4.10 Ethical and Regulatory Considerations: As medical implants become more complex and linked with digital health ecosystems, ethical considerations about patient privacy, data security, informed consent, and equal access to healthcare services become increasingly important. To guarantee patient safety, data integrity, and ethical standards are maintained, regulatory frameworks must change to reflect the rapidly changing medical implant industry^64,65.

5. CONCLUSION:

In conclusion, the review of medical implants highlights the critical role these devices play in modern healthcare, providing relief from a wide range of ailments, including orthopedic injuries, cardiac, breast, face, penile, and neurological diseases and beyond. Materials that are carefully selected for their particular qualities and appropriateness for design the medical implants. Every material, including silicone elastomers, titanium alloys, and stainless steel, has special benefits including strength, biocompatibility, and resistance to corrosion that make them appropriate for a range of implant designs and clinical situations. Additionally, emerging trends and innovations in biodegradable implant such as 3D printing, smart implants, nanotechnology, and regenerative medicine hold the potential to influence the direction of medical implant technology and open the door to individualized, minimally invasive, and extremely successful treatment modalities.

6. CONFLICT OF INTEREST:

The authors declare no conflict of interest, financial or otherwise.

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Received on 30.12.2024 Revised on 20.02.2025

Accepted on 10.04.2025 Published on 23.04.2025

Available online from April 26, 2025

Asian J. Pharm. Tech. 2025; 15(2):157-165.

DOI: 10.52711/2231-5713.2025.00025

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Creative Commons License.

FDA Classification	Examples	Description	References
Class I	Tongue depressors, Bandages, Elastic bandages	Low-risk devices with general controls	[13, 17]
Class II	Powered wheelchairs, Infusion pumps, Surgical drapes, Pregnancy test kits	Moderate to high-risk devices with special controls	[13, 17]
Class III	Implantable pacemakers, Heart valves, Silicone breast implants, Automated external defibrillators Intraocular lenses, Deep brain stimulation (DBS)	High-risk devices requiring PMA	[13, 17]