At what age can I start applying Botox?Lip augmentation with fillers should not be a painful procedure as long as the injector uses the proper technique. The best way to avoid a painful application is to numb the lips with a dental nerve block before the injection. Inferior alveolar nerve blocks are used in dentistry to offer an acceptable level of anesthesia in dental implant surgery. The same technique may be used in lip augmentation. Without a nerve block, the procedure can be extremely painful.