**1.3. Physics of laser surface texturing**

aesthetics. This leads to ongoing expansion and discovery in the technology and science

This chapter describes a research opportunity for the investigation and improvement of the effects of laser surface texturing on enhancing the biocompatibility and bioactivity of titani‐ um. Titanium substrates are used to examine the effects of key laser process parameters, including power, scanning parameters, and frequency on their surface topography proper‐

Cell adhesion and biocompatibility are important parameters for implant fabrication and the production of biomedical devices. Improvements to an implant's performance in the implan‐ tation site could benefit the patient's quality of life. Low biocompatibility is often caused by poor integration of the implant with surrounding tissues. Cell behaviour on biomaterial surfaces depends upon implant‐cell interactions, which are correlated with surface proper‐ ties such as hydrophilicity, roughness, texture, chemical composition, charge, and topogra‐ phy properties [6–8]. Although there is a great range in the design and function of various implants, the one common factor for all of them is their biocompatibility, which affects overall implant performance. Biocompatibility enhancement of materials used in implants is current‐ ly an essential challenge in implant engineering [8]. This property is essential in order to avoid any infections and immune system rejection. It can also affect the healing process by reduc‐ ing the healing time. A reduced healing time is desirable in implant applications, since the sooner the body accepts the implant organ, the sooner the user can function normally [7, 9, 10].

The implant's surface is the main area in contact with the body at an implantation site. Therefore, to increase the biocompatibility of a material, various methods of surface treat‐

One method to affect the surface properties of a material is to alter the surface topography properties. There are multiple conventional methods used commercially for processing and surface texturing of materials for bone and tissue implant applications [9, 11]. The most common mechanical methods for altering surface topography properties include sandblast‐ ing and machining, while acid etching and oxidation are common chemical methods. Although these methods are effectively used in industry, there are major disadvantages associated with them. Slow production time, complex control processes, and chemical contaminations are only a small number of the challenges presented by these commonly used processing techniques [13]. The newly developing method of laser surface texturing of materials addresses these disadvantages in a simple and effective manner. Lasers are able to deliver very low to high energy with extreme precision in dimension, spatial distribution, and temporal distribution. Lasers offer better control and precision, offer more feasibility, and are environmentally friendly [14–16]. Decreased processing time makes lasers particularly suitable for mass production, rapid prototyping, and custom‐scale manufacturing for a wide variety of

associated with biomaterials and implant engineering [3–6].

ties and biocompatibility.

356 358High Energy and Short Pulse Lasers

**1.1. Main challenge in implant engineering**

ment are currently being used in industry [9, 11, 12].

**1.2. Fabrication methods of biocompatible materials**

Laser processing can be applied in two categories based on the energy requirements: first, applications requiring relatively low energy with limited structural and physical changes; second, applications calling for high‐energy transformations for significant structural changes over a large volume, such as welding. Energy transformation in applications involving lasers requires the coupling of the laser radiation with the electrons of the interacting surface, such as metals or semiconductors [17, 18]. In return, the speed of energy transformation from the laser beam to the surface becomes fully dependent on the nature of the interacting material and its chemical bonding. There have been significant improvements in energy transforma‐ tion of lasers through the development of ultrashort lasers [19–23].

Ultrashort lasers decrease the interaction time (pulse duration) between the laser and the material, which reduces the effects on the bulk material. Despite these improvements, ultrashort laser systems are relatively expensive and cannot be utilized in industries. Hence, depending on the nature of the application, less expensive yet advanced laser systems, with pulse durations in the range of nanoseconds, are more popular among manufacturers because they are more widely available in manufacturing sectors. An understanding of the laser irradiation mechanism is required to utilize the more common lasers to their fullest capabili‐ ty, therefore, choosing the laser parameters is essential to the final quality of a particular application [24–27].
