Updated: May 10, 2020
*May 10, 2020 Update: We appreciate the positive feedback from those reading our blog. We are also honored that Convergent Dental, including CEO Mike Cataldo, reads our blog as well. He reached out to us to clarify a few points we originally commented on – specifically the intended benefits of the 4.2 update as well as the necessary minimum air-sheath air pressure. According to their studies, the minimum air-sheath air pressure needed to properly clean the gold turning mirror is 2 PSI. All three user controlled air settings are higher than this in the 4.2 update. It is our personal preference that this air-sheath air pressure be kept higher to all-together avoid even the remotest possibility of decreased cutting efficiency. We do acknowledge that this preference is our own opinion, is largely based on anecdote and that it’s hard to prove EXACTLY what is decreasing cutting efficiency due to the multi-variable nature of laser cutting efficiency. We’ve edited our post to reflect the new information and this line of reasoning.
The 4.2 update brought with it some real improvements, especially for Model 3 users. However, ever since the update to software version 4.2, there has been a lot of misunderstanding on what is actually happening when we use the new feature to “turn the air down” on our Solea handpieces. I’ve expressed to a few people that I did not like the cutting I was experiencing after the 4.2 update except in a few instances where the low air setting really does decrease patient sensitivity. As it turns out – and after talking with Mike Cataldo, CEO of Convergent Dental, those few instances where the laser performs better represent the intended improvements of the 4.2 update; we will get to those instances in a moment. Before that, however, I’d like to address exactly how the air system in Solea works, which is often misunderstood.
After digging deeper into the update and having an in-depth conversation with a very knowledgeable Solea technician, I’ve learned a few interesting things that I’d like to share that will help improve clinical outcomes. What you need to know about Solea is that there are 2 different air pressures coming out of the handpiece. The input air is 45 PSI and is split into two different air pressures: there is something called ‘air-sheath’ air and then there is mist air (coolant air). The air-sheath air is what you hear and feel blowing out of the handpiece when the laser foot pedal is not activated. Air-sheath air is air designed to blow across the gold turning mirror and keep it clean of debris during your procedure. Air-sheath air has traditionally been 25 PSI, or what would now be classified as “high air” with the 4.2 update. The 4.2 update now provides the user the option to change the air-sheath air to 17.5 PSI or as low as 10 PSI – though the touch screen does NOT clarify that you are changing air-sheath air specifically.
The other air coming out of the Solea handpiece is the misting air and THIS is the air that mixes with the water to create a mist. It is 20 PSI and has not changed since the latest 4.2 update. To be clear, the misting air is mixing with the 13mL/min of water to create the mist . Also, the user currently does NOT have the option to change the misting air pressure.
So when you’re changing the new air setting on your Solea unit to either high, medium or low, you are changing the air-sheath air pressure specifically. It’s not affecting the misting at all.
Let’s get back to those rare instances where the “low air” setting has helped. What are those instances? They are primarily (1) class 5 dentin hypersensitivity and (2) recurrent caries around composites where no significant enamel is present to establish analgesia. Why is that? My theory is that these patients are often complaining of the air-sheath air blowing on their tooth PRIOR to activating the laser. It’s when we “hover” over the area and are desiccating the tooth with air-sheath air that patients feel the sensitivity. This is exactly the same result you’d get if you dried the tooth with the air-water syringe and the patient feels that zing! Once the procedure starts and the laser is actively pulsing and the water is misting, we know that patients are more comfortable and teeth are less sensitive.
Accordingly, it may make sense to have the air sheath air controlled by the foot pedal. When the laser is not engaged and the gold turning mirror does not require air-sheath air, maybe it should be off or at the minimum flow of 2 PSI. However, when the laser is activated by the foot pedal, automatically switch the air-sheath air to whatever flow has been selected on the touchscreen. This way we might be even less likely to “zing” the patient.