Dr Zohaib Ullah provides an introduction to lower facial aesthetics and explores the use of injectable treatments in the area.
Facial aesthetic treatments with the use of botulinum toxin and hyaluronic acid (HA) soft tissue fillers have come a long way since they were first introduced. Main indications related to facial aesthetics continue to be localised to the use on the upper face.1,2 However, treating the lower face with botulinum toxin and dermal fillers is now common practice among medical aesthetic professionals. To undergo safe and successful treatment, practitioners must consider the structure and function of the lower face, and understand how to approach each anatomical region.
When assessing the patient, practitioners can use a three-zone approach to the face, which comprises three main areas – the upper, the mid and the lower face (Figure 1).3 Any changes to the mid-face (ie: cheek volume) subsequently also influence changes to the lower part of the face. As we age, not only our skin, but the underlying muscles/fat pads and bone structure alters. As with the effect of gravity, any loss of volume or laxity to the mid-face will produce a pronounced loss of lower face structure and aesthetic appeal. For purposes of this article, we will be focusing on the lower face; however, it is still key to assess the patient using the three-zone approach to achieve a truly satisfactory aesthetic outcome. The lower face can be broken up into the perioral, the jawline and the chin, which each have their own subsection, as demonstrated in Figure 2.3
Botulinum toxin and HA fillers can be used to treat the lower face for a variety of indications. Botulinum toxin treatment is performed for the relaxation and restriction of movement of the underlying muscles, and dermal fillers are used for restoring volume and support for deeper soft tissues. For each area and subsection, we will try to evaluate the safety and efficacy of both botulinum injections and dermal fillers with the objective of providing a complete aesthetic outcome. In general, both botulinum toxin and dermal fillers, in experienced and knowledgeable hands, are very safe. Procedural awareness, injection technique and skill is key, as well as a sound understanding of the patient’s anatomy and a good, careful, medical and treatment history will help to ensure good patient selection.
Given the perioral area is the region used for speaking, eating and breathing, amongst other things, it is an area which should always be considered when assessing the lower face for rejuvenation. The lips are the main feature of this region and are more commonly associated with purely dermal filler treatment. This is because, as we age, we lose both shape and volume. Latest fashion trends have suggested that plumper, fuller lips with good definition are popular and deemed to be more aesthetically pleasing, as evidenced on social media by popular celebrities and ‘influencers’. The lips are a truly delicate area and when using dermal fillers, the margins for error are comparatively small. This is because the plane in which the product is placed is, at best, only 1-2mm in width,4 so it can be very easy to inject into the underlying musculature rather than the correct plane.
Given the properties of dermal fillers, and the added tendancy to involve anaesthesia, they have a hydroscopic e ecy and draw in fluid, which will almost always result in a more swollen appearance, so good counselling on post-procedure visual outcomes is a must to manage expectations. Inadequate experience, as well as injecting into the lips, can also lead to extensive bruising, and can present ‘lumps’ of the product forming if not carefully administered. Long-term reactions, including granulomas, are rare but not unheard of, with many level 4 evidence case series documenting this.5
There is also a role for toxin to be used in the surrounding radial/lips lines. By applying toxin to the perioral lines superficially, practitioners can smooth out, soften and often remove lines, providing a much more complete perioral aesthetic outcome. Large amounts, or incorrectly placed toxin, can result in lip paralysis and so care needs to be taken. Level 2 evidence has suggested that injections are therefore best done using small amounts with regular top ups in the first instance.6 The increase in depth of the oral commissure with age can result in the typical ‘sad’ smile. Again, affected by surrounding tissue droop and skin laxity, it is an area also directly controlled by the depressor anguli oris.8 By injecting the depressor anguli oris with botulinum toxin, we can help improve the commissure’s shape, giving a lift, also improving marionette lines. Adding dermal filler into this region will help to not only stabilise the oral commissure, but also to add volume to the marionette lines that so readily form in this area, due to the ageing process.9
A combination of mid-facial changes, including skin laxity, soft tissue volume loss and structural bone changes, can make the jowl area difficult to treat. This is especially if the practitioner is only focusing on the lower face. A combined approach should always be used with the mid-face to help improve this area. Dermal fillers can be used in the volumisation of the cheeks to try to raise this region.8 I have found that using dermal fillers just anterior to the jowls can help to reshape and define the jowl borders in isolation. More commonly however, it is at this point where radiofrequency/PDO threads, and ultimately surgical lifts are required if all above methods to stabilise the mid-face fail, but as we are focusing on toxin and fillers, these will not be discussed in detail.
Masseter hypertrophy is an aesthetic concern for many as it gives the look of a widened mandible. This is not only an aesthetic but also a medical concern, given that some patients complain of troubles with mastication, as well as subsequently painful jaws due to teeth grinding (which theoretically causes the hypertrophy in the first place). The use of toxin in the masseter allows for relaxation of the muscle and, over time, reduction of the masseter muscle itself.9 Many case studies have shown the beneficial effect of toxin use in this area, with statistically significant mean masseteric volume reduction, including when performed in comparison trials with photographic confirmation.10,11,12 One level 4 study comprising 22 participants reported up to 30% reduction in mean masseteric volume.13 Complications, however, do include possible damage to the mandibular branch of the facial nerve, change in mastication forces, speech disturbance due to overdosing and occasionally muscle pain, facial asymmetry, and prominent zygoma, demonstrated in a study with level 4 evidence.14
When assessing the patient, practitioners can use a three-zone approach to the face, which comprises three main areas – the upper, the mid and the lower face
It is generally accepted that there are two main issues when it comes to the chin. One is the dimpling effect caused by the mentalis muscle, and the other is no chin volume secondary to hereditary bone definition. The chin is a good example of where toxin and fillers can both work hand in hand. Chin rhytides are caused by the dermal atrophy of the mentalis. This can cause an unsightly dimpling effect when facial expressions are made.15 Toxin injected into the rhytides superficially is of great use as it helps to not only smooth out wrinkles, but also to improve facial expression, thus resulting in a more uniform and levelled chin.16 When it comes to adding volume and prominence to the chin, the use of a dermal filler will always help to contour the chin and provide a great aesthetic outcome.17 The injection sites need to be accurate; product should be placed between tissue and bone, to avoid the neurovascular bundle that runs close by.15 This not only limits complications, but also provides a firm base by which to stabilise the mentalis and provide good lift and definition.18
Both botulinum toxin and HA fillers have potential side effects, some of which have been discussed in the relevant sections above. Although infrequent, attention to detail in injecting safely and correctly, added with good clinical knowledge, are key to minimising risks involved. Botulinum toxin side effects can range from simple headaches, which are more common,19 to more serious side effects such as eyelid disorders and the absolute worst case scenario, eyelid ptosis.20 Vascular compromise is known to be the major adverse event to look for when injecting HA fillers, although others can include local inflammatory reactions, inappropriate placement and technique-related issues. Although these side effects are possible, they are relatively rare, especially the most catastrophic – blindness due to vascular occlusion.21,22
The lower face is frequently treated with varying techniques, doses and outcomes. Both HA fillers and botulinum toxin have a relatively safe profile and, in experienced and knowledgeable hands, can provide fantastic results. However, it is always good to be aware of complications as when they do occur as they can be life changing. Combining treatments, of course, helps to provide much more superior aesthetic outcomes rather than if treated in isolation.23
Upgrade to become a Full Member to read all of this article.