Comparing Surgical CO₂ Laser Technologies

According to American Dental Association (ADA) Guide on Dental Lasers, “for erbium laser wavelengths, optical absorption and coagulation depths are significantly smaller than gingival blood vessel diameters. Coagulation takes place on a relatively small spatial scale and in general – based on these particular factors – does not prevent bleeding from the blood vessels severed during tissue ablation.” Furthermore, “the optical absorption and coagulation depths for the CO₂ laser wavelengths are effective within the diameters of surface gingival blood vessels. Coagulation extends just deep enough into a severed blood vessel to stop the bleeding.” Examples of Erbium laser wavelengths include Waterlase by Biolase at 2,780 nm and LightWalker by Fotona at 2,940 nm. Examples of CO₂ laser wavelengths include LightScalpel at 10,600 nm and Solea by Convergent Dental at 9,300 nm.

When exploring surgical CO₂ lasers, it is important to understand the technology behind various beam delivery systems (for example, see Figure 1, which compares glass tube articulated arm (left) to flexible fiber waveguide (right) CO₂ lasers). An educated decision will allow clinicians to purchase the most durable, efficient, and profitable laser for their practice.

The LightScalpel laser’s design includes the following critical components (see Figure 2):

all-metal laser tube;
low voltage 32 volts DC and RF power supplies;
heat exchanger;
beam delivery system;
laser power meter;
beam attenuator – shutter;
devices monitoring the performance of all critical components 1 through 6;
user control panel;
fiber calibration port;
software program controlling all the hardware items 1 through 9; and
safety ‘watch-dog’ software program monitoring items 1 through 10.

Figure 1. The difference between old and new technologies is vast

Figure 2. LightScalpel surgical and dental CO₂ laser.

The latest generation of flexible fiber surgical CO₂ lasers – the LightScalpel LS-1005 and LS-2010 lasers – features the best in flexible fiber waveguide technology to enable the highest laser beam quality delivered to the surgical site.

Flexible Fiber Waveguide

Flexible fiber waveguide surgical CO₂ medical and dental lasers shown in Figures 2 and 3 have been the dominant technology since the mid-1990s. Resilient, long-lasting flexible fibers enable compact, ergonomic handpieces to have a scalpel-like feel, featuring pinpoint accuracy, as well as enhanced flexibility and accessibility for surgeons. On the contrary, the articulated arm shown in Figure 3 is an old technology (developed in the 1970s – 1980s).

All Metal Laser Tube

Durable and reliable all-metal RF excited CO₂ laser technology (seen in Figures 2 and 3) is dominant in medical applications (tens of thousands of installations), industrial applications (hundreds of thousands of installations), and military laser applications in the power range of 10 – 10,000 watts. This is the ONLY proven and reliable technology that allows for fast, inexpensive service in very demanding industrial settings for cutting, welding, engraving, printing, marking and coding, etc.

In contrast to all-metal surgical CO₂ lasers, antiquated fragile glass tubes (1970s technology) seen in Figure 3 are difficult to service. Flowing liquid is needed to prevent the glass from cracking, which is caused by the intense heat generated by electric discharge plasma inside the laser tube. A very high voltage, over 10,000 volts, is required to operate plasma in such glass tubes. Neither eroded electrodes nor metal sputtered glass tube walls are serviceable, which often calls for laser tube replacement rather than repair. These reasons, among others, (including difficulties with glass tube plasma pulsing and turning on, severe limitations on laser pulse width, laser power stability, laser beam quality, etc.) have allowed all-metal lasers to replace glass tubes in virtually all industrial and most medical applications since the mid-1990s.

Fiber / Laser Beam Power Calibration

LightScalpel is the only surgical CO₂ laser on the market with the ability to verify (daily or however frequently) that laser power at the distal end of the beam delivery (handpiece) matches the laser power value selected on the control panel. Verification is achieved through the calibration port on the side of the laser as shown in Figure 2.

When using a competitor’s foreign-made CO₂ laser without distal calibration capabilities, the clinician does not have a way to determine how much laser power is applied to the patient.