Effective applications of botulinum toxin in dentistry and in head and neck surgery
Figure 6. Points for application in treatment of Gummy smile.
application requires a small amount of botulinum toxin. Based on the author’ s experience, it is a very effective and efficient procedure. However, it is one of the most interesting indications in the whole of dentistry. 4.2.2. Application into the Orbicularis oris muscle Although an application to the lower face is demanding and still not approved by regulators, it is frequently used in many cases even by beginners or physicians, not specifically trained in the botulinum toxin. The application of a small amount of botulinum toxin into the orbicularis oris muscle smooths very unpopular transverse wrinkles. Nevertheless, it is extremely demanding to catch a fine muscle without control by an imaging technique. It is always necessary to count with the weakening of the Orbicularis oris muscle function, which leads to the limited capability of the mouth to retain drinks and food. Surprisingly, this complication is well tolerated by patients, in particular by women, but they should be informed about this frequent side effect in advance. Other consequences of weakening the Orbicularis oris muscle are asymmetries of the face which are not so well tolerated. They could be corrected only by the further deepening of the muscle paresis, or by fading which could take a few weeks or months. Typically we use four points for the application regularly distributed over the circumference of the muscle with half the amount of the drug compared to the amount applied in another area of the face. 4.2.3. Elevation of the mouth corners Application of botulinum toxin into the Depressor anguli oris muscle, or to the Platysma muscle is the most popular solution for " slack " corners of the mouth that can escalate from simple visual problem to the inflammatory disease. It is, however, important to note that the most common cause of this problem is the reduction of the intermaxillary position or teeth abrasion. The primary treatment for slack corners should be made by a dentist because it prevents some serious complications, such as the damage of the temporomandibular joint. The solution with
botulinum toxin 25 should be effective only for patients where dental treatment cannot resolve the problem completely or if the patient refuses the dental solution due to associated risks. We can use the botulinum toxin as an adjuvant treatment to escalate the effect of the dental treatment. From many possible schemes, we use in our clinical praxis the application in two points at the edge of the mandible affecting not only the Depressor anguli oris but also the Platysma muscle. The muscle insertion is easy to find and palpate in this location. 4.2.4. Applications to the mimic facial muscles of the lower facial third Bone borders allow us to intervene relatively safely into the group of lip depressors and elevators, which can correct the smile line of the patient, a key parameter of aesthetic dentistry. It is relatively easy to determine the position of the jaw muscles. However, it is always vague to hit the orbicularis oris muscle, and it is nearly impossible to target the precise orientation of the Risorius. The future approval of the applications in this area( lower facial third) is probably possible only with the ultrasound navigation which is safer, and it is also approved for some other applications of the botulinum toxin( e. g. sialorrhea). 26 Our clinical experience shows a decreased rate of complications with ultrasound guiding. 4.3. Guidelines We have no specific guidelines for dentistry and oral surgery yet but it is possible to find the latest recommendations in the field of Aesthetic Medicine in the guidelines of specialised societies, one of the most accepted being the American Society for Aesthetic Plastic Surgery( ASAPS), with frequent updates in their journal or online. The application of the botulinum toxin as a treatment possibility for pathologies in the head and neck area is, except for a few indications( a migraine), a new domain with few scientific papers, and we are waiting for treatment guidelines.
5. Conclusion The rapid development of the botulinum toxin application brings new possibilities for treatment by dentists alone or in cooperation with other specialists. Besides the above-verified evidencebased indications, there are new and new case studies quickly appearing that need to be monitored and possibly applied. But we have very few randomised studies to make final guidelines in many indications, so further scientific works are really needed. The botulinum toxin should be part of undergraduate and postgraduate teaching.
Author Contributions Equal contribution to the paper. Acknowledgments The author reports no conflict of interest and there was no external source of funding for the present study.
Review Articles
Stomatology Edu Journal
205