August 11, 2022

3d lip anatomy

Vertical or horizontal injections? Which do you favour when it comes to lip augmentation and enhancement treatments? It is a much-debated topic, and it is no wonder that many aesthetic clinicians find it a real dilemma.

In this blog, Dr Tim Pearce explores whether there is a greater risk of vascular occlusion with vertical or horizontal injections in the lips, and how you should approach your technique to avoid the labial arteries. He will help you to understand the true depth and position of the arteries using 3D imaging, a new resource available as part of Dr Tim’s Ultimate Lip training course that is launching soon.

Do you feel anxious about causing complications? Many clinicians feel so overwhelmed with the thought of causing a vascular occlusion that it stops them growing their aesthetics business. Dr Tim is currently hosting a webinar series to help you overcome your fear of complications so that you can uplevel your knowledge and increase your CPD-certified learning to build a successful aesthetics business. Sign up here >>

Why 2D anatomy drawings and textbook descriptions cannot give you a true 3D picture of the lips

Treating lips is tricky. Dr Tim recalls a discussion he had with another very well-known aesthetic clinician where they disagreed on some fundamental anatomy surrounding the location of the labial artery, in relationship to how we inject the lips, and whether a vertical or horizontal injection approach is better.

During this discussion, the conclusion in a particular clinical paper was raised as it highlighted that a vertical injection might be riskier than a horizontal approach. This made Dr Tim stop and think, and he realised that it all came down to the wording – the claim was made that the labial artery runs in the wet-dry border of the lip, not a location where Dr Tim had been picturing the artery, and this made him feel a little uncertain about his established thinking. Of course, this often happens to newer injectors – you think you have finally understood something, and then along comes someone notable or well-respected and they say something different; your clinical mind is blown, or you suddenly worry that maybe there are all sorts of things that you believed to be true, that may not be, and you question your practice.

So, what did Dr Tim do to help him understand this difference in understanding? He started diving into the detail of the quoted clinical papers and even began looking at other published studies on facial and lip anatomy and the position of the arteries.

He soon discovered something very interesting, and that is what he wants to share in this blog…it became apparent that a lot of the ways these very complex, three-dimensional anatomical structures are described – when you put them into words in a textbook or published in a journal – makes them seem different from different perspectives and interpretations.

A good example for illustration is this idea of the wet-dry border or vermilion border, and the question, where is the artery? Some studies will categorically state that the labial artery is at the level of the wet-dry border, meanwhile others will state, with just as much certainty, that the labial artery is in the vermilion border – and it was this clash of descriptions that got Dr Tim thinking. It can be so difficult for aesthetic clinicians to be certain about the location of the artery when things are described, in the literature, so differently, but it all boils down to reference points, scale, and precision.

Reference points, scale, and precision in lip anatomy

Let’s consider scale. The thickness of a needle is 0.4mm. When a text describes something (in this case an artery) as being at the wet-dry border or in the vermillion border, it will sound, when you first read it, as if it is at the exact point where you are inserting your needle, but this is not the case. This area encompasses 4-5mms so is likely nowhere near the location of your needle – the problem here is scale and the lack of precision in the words used to describe the exact location of the artery. The vermilion border or wet-dry border are very vague terms, and we need to realise that there is a likely imprecision when it comes to the width of a needle versus the position of the artery.

Of course, when you hear different descriptions of the same thing it creates this uncertainty. Dr Tim believes that a three-dimensional or 3D understanding of the lip anatomy will give you much more confidence that you are in the right place when injecting.

Introducing 3D lip anatomy tools

Things will become clearer if we look at them from a three-dimensional point of view. The following 3D images are taken from a tool used in Dr Tim’s upcoming Ultimate Lips training course.

labial artery position front view
If you look at the image above straight on, you can see that the labial artery is very neatly at the level of the vermilion border.
labial artery position angled view
However, as soon as you start to rotate the view and look at it inferiorly, it looks like it is moving down and deeper because those arteries are about 5mm deep.
labial artery position top view
If you look at it from the most inferior aspect, it is at the level of the wet-dry border, thus, both these different ways of describing the lip anatomy and artery location are correct.

However, what you really want is a combination of both views, then you will have a much clearer idea of the actual position of the artery relative to your injections, which are usually running in the anterior third of the lip and are therefore in a relatively safe place with respect to those arteries no matter which angle you choose to inject.

Which are safer, vertical or horizontal injections into the lip?

Whether you are vertical or horizontal does not seem to matter, so long as you are anterior enough, you should be missing the vessel. Now, of course you are still going to ask – which angle of entry is safer?

Dr Tim would rather that we did not get fixated on this one aspect of the injection procedure and instead considered other crucial factors relative to your overall injection technique.

Both vertical and horizontal approaches can be safe, so long as your depth is correct. This is a much more important consideration than your angle of entry. The depth of the labial artery is on average 5mm in a young lip, but this might change slightly depending on the fullness of the lip and will change with the age of the lip.

In a very old person, you will notice the lip has elongated and some of the pink has rotated back within the lip. When you perform a vertical injection, you are necessarily at a different angle than when that same person was in their youth because then they had the pink part of the lip rotated upwards and your angle of entry would have been roughly 45 degrees. As they get older, you end up pointing your needle behind the muscle where the artery lies. Thus, it is a cautionary tale, as, in theory smaller lips and older lips require a steeper angle of entry and end up with the tip of your needle being closer to the posterior section of the lip where the artery tends to reside.

There is a small difference in risk whether you are vertical or horizontal. Because the artery runs horizontally, you are going to spend more time parallel with it using a horizontal injection. Dr Tim performs horizontal injections all the time and believes they are safe if performed correctly. He prefers using horizontal injections due to the goal of creating a shape than tends to involve enhancing the vermillion border and the area close to it, using very superficial injections.

The debate between horizontal or vertical injections is somewhat a two-dimensional debate but Dr Tim believes the solution lies in three dimensions, as shown in the images above and his fantastic new 3D imaging tool.

Learn more on avoiding vascular occlusions by understanding 3D lip anatomy.

Got any burning questions about treating lips? Why not post your question on social, you can find Dr Tim Pearce on Instagram.

Aesthetics Mastery Show

For more insight, watch the latest episode of the Aesthetics Mastery Show, where Dr Tim shares how to inject the lips to avoid the labial arteries and explains whether there  is greater risk with a vertical injection vs a horizontal injection. He also shares a look at the anatomy of the lip in 3D, so that you can understand the true depth and position of the arteries when injecting.

The show has thousands of views already, plus comments and feedback from other practitioners:

“This was the best information (for me) because I’ve some how manage to hit an artery-vessel…while injecting my lips. Without fail I either hit one either on my upper lip or my philtrum. Maybe I should use PDO threads in these areas? Could you or would you give me your opinion? Thank you for ever single piece of content that you selflessly give. I’ve learned so much from you Dr. Pearce. Again I want to thank you and Miranda.”

Jennifer Morris

As well as appreciation:

“I love watching your videos and find them so helpful to improve my practice. Thank you!”

Laura Henderson

Is your worst nightmare causing a VO?

If you want to be a great injector then you need to get over your fear of complications. Register here for the next webinar to help you overcome your complications anxiety >>

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Lip Filler Treatment & Complications

With all the conflicting advice out there about lip filler treatments – vertical or horizontal? needle or cannula? – it can be difficult to know how to inject to create the lips your patient desires.

If you are suffering from technique overwhelm, worrying about causing a vascular occlusion (VO), or panicking about injecting thin lips, then Dr Tim Pearce’s brand-new ultimate lip course is going to teach you the different techniques, anatomy, and skills you need to create medically beautiful lips.


Dr Tim Pearce eLearning

Dr Tim Pearce MBChB BSc (Hons) MRCGP founded his eLearning concept in 2016 in order to provide readily accessible BOTOX® and dermal filler online courses for fellow Medical Aesthetics practitioners. His objective was to raise standards within the industry – a principle which remains just as relevant today.

Our exclusive video-led courses are designed to build confidence, knowledge and technique at every stage, working from foundation level to advanced treatments and management of complications.

Thousands of delegates have benefited from the courses and we’re highly rated on Trustpilot. For more information or to discuss which course is right for you, please get in touch with our friendly team.

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