ADVERTORIAL: NASHA (RESTYLANE)
Cheek and chin augmentation
Dr Bob Khanna describes his techniques for chin and cheek augmentation with non-animal stabilised hyaluronic acid
The chin and cheek play an important role in facial harmony. The chin has been associated historically with character definition, and high cheekbones confer a look of femininity and youthful vitality.
Patients are increasingly seeking less-invasive corrective procedures because they are nervous of surgery, cannot commit to the required down-time or choose temporary enhancement to see potential benefits before committing to surgery. Non-permanent dermal fillers enable us to offer patients highly effective, non-surgical contouring for the chin and cheek areas.
The non-animal stabilised hyaluronic acid (NASHA) product, Restylane SubQ, with its large particle size (1000 particles per ml) and greater thickness and viscosity, has proved invaluable as a subdermal, submuscular and supraperiostal filler. NASHA is supported by extensive safety and efficacy data, and published clinical experience of its use in the chin and cheek area demonstrate long-lasting efficacy, typically between 9-12 months.
Non-surgical chin augmentation is a large component of my aesthetic practice, representing about 25% of my cases. Patients' needs vary from mild sculpting to improve facial balance to more extensive treatment that would traditionally have prompted surgical resolution. In all cases, I use NASHA in a gradual, three-dimensional contouring and sculpting of the chin. When injecting into this facial area, important anatomical features include the lower lip depressors, notably, the mentalis and the depressor labii inferioris, and the mental neurovascular bundle.
As with all aesthetic treatments, I thoroughly cleanse the skin with topical antiseptic to avoid the risk of subsequent infection. I usually mark-up the area for augmentation before numbing, as I find that anaesthesia can create tissue distortion. I mark the centre line of the treatment area by drawing a vertical line from the lower lip to the inferior margin of the chin. I also mark the outer lateral boundaries, giving myself a safety margin of 1cm minimum from the mental foramen (usually found between the roots of the lower pre-molar teeth) to avoid potential problems with compression of the nerve or vascular supply.
For chin augmentation, I usually administer two intra-oral mental blocks and then deeply infiltrate the centre of the symphysis region so that a total of 2-3ml of lignocaine plus 2% adrenalin is used. Topical anaesthesia is an option, but local anaesthesia ensures a totally pain-free procedure. I usually inject with the patient sitting semi-upright, which allows me to consider gravitational effects at all times. My choice of needle size varies from 18G to 23G; I try to avoid the need to make multiple punctures but still achieve wide access to the treatment area by using a needle of at least 1.5 inches in length. In a mild augmentation, I access the area centrally just beneath the mandibular border. In moderate or extensive cases, where I am using larger volumes of the hyaluronic acid gel, I usually access the area laterally and inject towards the midline, as I find this a better approach.
Non-animal stabilised hyaluronic acid (1000 particles per ml) can be placed either supraperiostally, beneath the muscle layers and along the mandibular bone, or in the deep subdermal tissue, depending on the extent of augmentation required. In mild or moderate cases, I usually place the HA gel subdermally. However, in more extensive augmentations, I place it supraperiostally to avoid over-augmentation in the immediate subdermal plane and to provide a platform for the addition of further layers in the subdermis if required.
I inject between 0.5-1.0ml of Restylane SubQ at a time, evaluating and adjusting the procedure after each injection to ensure optimal aesthetic results. I re-enter the skin via the same injection point each time. When the procedure is complete, I apply careful directional massage to sculpt the area and ensure there are no step tissue deformities. I tend to use 1-2ml for a mild augmentation, 2-4ml for a moderate augmentation and more than 4ml for an extensive augmentation.
Cheek augmentation helps support the lower facial tissues and achieves a mid-face elevation. Important anatomical features in this area include branches of the facial nerve, in particular the zygomatic and buccal branches, the infraorbital nerve and vessels and the parotid duct. It is important to note the position of the zygomaticus major and minor and orbital aspect of the orbicularis oculi and the relationship of the superficial musculo-aponeurotic system (SMAS).
I have found that dividing the cheek into upper, middle and lower areas helps me plan a staged approach to treatment. A stage-one treatment is usually all that is required in younger patients; however, older patients often need stage-one, -two and -three treatments, sometimes with the addition of a tear trough augmentation.
For an upper cheek augmentation, I inject no closer than 1.5cm from the orbital margin. Therefore, after cleansing the lower face thoroughly with topical antiseptic, I mark the orbital rim as my outer limit. I then draw a line down the face, starting at the mid-pupillary line to define the anterior extent of the augmentation. I continue back posteriorly to create an anterior-posterior extent of about 6cm while the superior-inferior extent is between 2-3cm; although, dimensions vary according to the patient. When marking the mid-cheek area, I extend a further 2-3cm inferiorly from the upper cheek. I extend the lower cheek compartment inferiorly up to a further 4cm, as far as the level of the oral commissure and sometimes commensurate with the buccal fat.
As with the chin, it is possible to use topical anaesthesia, especially if only treating the upper cheek. For patients who are nervous or would prefer a totally pain-free procedure, I usually infiltrate the area with about 0.5ml of lignocaine plus 2% adrenalin, injecting the anaesthetic about 1cm posteriorly to the entry point. Anaesthesia of the mid- to lower-cheek region to block the infraorbital nerve is achieved with a deep infiltration of local anaesthetic, administered intra-orally.
Although some clinicians use a cannula to place the HA gel in the mid-face, I find that a rigid needle provides tactile feedback and helps achieve greater control and precision. I tend to use a needle size between 18 and 21G and, to ensure that I can access the whole treatment area, one of at least 1.5-2.5 inches in length. In the upper cheek, I place the NASHA just supraperiostally or in the suborbicularis oculi fat (SOOF) and follow the contour of the bone to accentuate the natural contour of the zygomatic arch and malar prominence. I insert the needle posteriorly, and inject between 0.5-3.0ml of NASHA depending on whether mild, moderate or extensive augmentation is required.
For the mid-cheek, I inject subdermally in the mid to deep subdermis to allow for the potential loss of fat and skin thinning. I use the same size needle (between 18 and 21G) and the same injection point for supraperiostal injection in the upper cheek and subdermal injection in the mid-cheek, but inject slightly smaller volumes, usually 0.5-2.0ml.
The entry point for augmentation in the lower cheek is about 3cm below the ala-tragal line. To avoid potential damage to the parotid duct, I inject 0.5-1.5ml into the mid-to-deep subdermis, ensuring the needle does not penetrate the oral mucosa by inserting a gloved finger into the mouth. This allows me to palpate the gel from inside the mouth. One problem with three-stage augmentations in older patients is thinner skin. In these cases, I tend to carefully manipulate the NASHA gel, before overlaying it with another, less-viscous NASHA product to create a smooth contour.
Managing patient expectations before, during and after the procedure is key to achieving success in facial aesthetics. I make an accurate and comprehensive assessment of the patient's face before discussing all aspects of the procedure. I discuss in detail what the treatment will involve and I emphasise the importance of following my after-care recommendations following treatment. Pre-treatment clinical photographs are an essential diagnostic tool and provide vital medico-legal records.
As part of my post-treatment recommendations to patients after chin and cheek treatment, I instruct the patient to avoid manipulation of the area and advise them to sleep lying flat on their back rather than on their side. I usually warn patients of potential post-procedural discomfort and recommend standard NSAIDs for a couple of days if required. Chin augmentation can sometimes cause temporary difficulty with lower lip mobility when smiling owing to a transient effect on lower lip depressor muscle function.
I usually review patients three weeks after treatment for a fine-tuning appointment and for post-procedure photographs. I check for patient satisfaction and assess the chin or cheek for any asymmetry, re-injecting with small volumes of NASHA to address small inaccuracies if necessary. As I adopt a careful and systematic approach to all my procedures, the need to do this is rare.
Dr Bob Khanna is a cosmetic and reconstructive dental surgeon with clinics in Ascot, Reading, Harley Street and Manchester. Dr Khanna is the president of the International Academy for Advanced Facial Aesthetics and is a clinical lecturer in facial aesthetics at the Royal College of Surgeons (London)