Journal of Dentistry Defence Section

: 2021  |  Volume : 15  |  Issue : 2  |  Page : 148--151

Ultra-low frequency-transcutaneous electric nerve stimulation for functional border molding and cameo surface recording for enhanced complete denture success: A novel approach

Vijaya Kumar Rajamani, Kirandeep Singh, Parag Dua, Poonam Prakash 
 Department of Dental Surgery and Oral Health Sciences, Armed Forces Medical College, Pune, Maharashtra, India

Correspondence Address:
Kirandeep Singh
Department of Dental Surgery and Oral Health Sciences, Armed Forces Medical College, Pune, Maharashtra


Ultra-low frequency transcutaneous electric nerve stimulation (ULF-TENS) is one of the therapeutic devices used for relaxation of orofacial musculature by the use of low frequency, low current stimulation of the certain branches of trigeminal and facial nerve. Complete denture fabrication is the most widely used modality for rehabilitation of completely edentulous maxillary and mandibular arches. Numerous efforts and techniques have been introduced to improve retention and stability of prosthesis, in order to improve form, function, esthetics, phonetics, and health of the patient. These include modifications in impression making and cameo surface recording to improve the adaptation of the prosthesis. Accurate tracing of functional borders during border molding and recording cameo surface of the prosthesis using ULF-TENS in patients with poor neuromuscular incoordination can play an important role in improving the stability and enhance the performance of the masticatory system. This clinical report describes recording of border molding and cameo surface using ULF-TENS in a completely edentulous patient, resulting in enhanced adaptation with adjacent stomatognathic system.

How to cite this article:
Rajamani VK, Singh K, Dua P, Prakash P. Ultra-low frequency-transcutaneous electric nerve stimulation for functional border molding and cameo surface recording for enhanced complete denture success: A novel approach.J Dent Def Sect. 2021;15:148-151

How to cite this URL:
Rajamani VK, Singh K, Dua P, Prakash P. Ultra-low frequency-transcutaneous electric nerve stimulation for functional border molding and cameo surface recording for enhanced complete denture success: A novel approach. J Dent Def Sect. [serial online] 2021 [cited 2022 Dec 4 ];15:148-151
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Complete dentures have been traditionally the mainstay for prosthodontic rehabilitation of completely edentulous maxillary and mandibular arches. Challenges arise from factors such as prolonged periods of edentulousness and severely resorbed residual alveolar ridges along with altered neuromuscular capabilities.[1] In such situations, it is ardent to accurately record intaglio surface of the prosthesis, which is harmonious with the adjacent stomatognathic system. Various authors have suggested modifications in functional impression techniques for better recording of extent of the prosthesis.[2] Cameo surface recording also plays an equally important role for providing stability to the prosthesis against the forces generated by muscles of the cheek and muscles of the tongue.[3] Accurate recording of cameo surface improves the stability, enhances the esthetics, and improves the phonetics. Different modalities such as neutral zone technique and peizography have been described for recording of cameo surface.[4] Bulbule et al. and Koli et al. have described transcutaneous electric nerve stimulation (TENS) for recording of cameo surface of the prosthesis.[5],[6] Ultra-low frequency (ULF)-TENS has evolved as a newer approach for recording of border molding and cameo surface.

This article presents a clinical report for recording of border molding and cameo surface recording of completely edentulous patient with poor neuromuscular coordination using ULF-TENS to accurately record the cameo surface.

 Case Report

A 65-year-old male reported to the Department of Prosthodontics and Crown and Bridge with a chief complaint of loose dentures for the past 2 years. On eliciting dental history, it was found that the patient had undergone extraction of all his teeth 2 years back, and subsequently the patient had been using two different sets of complete dentures but was not satisfied due to dentures being loose.

Extraoral examination revealed that the patient was having poor neuromuscular incoordination. The patient did not report any history of cardiovascular disease or any other comorbidity.

The clinical examination and radiographic evaluation diagnosed the patient as Prosthodontic Diagnostic Index Class I edentulous maxillary and mandibular residual ridges along with inflammatory myopathy.[7] A treatment plan was formulated to rehabilitate edentulous arches with conventional heat polymerized polymethylmethacrylate resin prosthesis, but considering the poor adaptation of the previous denture, we decided to use a novel approach for border molding and cameo surface recording technique using “ULF TENS.” Following a written consent, a United States Food and Drug Administration approved portable electrography pain-relieving device (BLD T250 Stimulator; Johari Digital Healthcare Ltd) was used for ULF-TENS. This apparatus consists of four electrodes, an amplitude controlling unit, a knob controlling the frequency of electric current, and a push button controlling the mode of delivery of electric current [Figure 1].{Figure 1}

Two electrodes of TENS apparatus were placed in preauricular region and two were placed in the posterior triangle region of the neck [Figure 2]. ULF-TENS application was carried out by gradually increasing amplitude of electric current from range of 0 to 4 mA, based on the subjective symptoms of the patients comfort. The patient was instructed not to touch any metallic items and to inform immediately in case of any discomfort. Initially, stimulation was done at continuous mode at a frequency of 4 Hz over a period of 40 min. Change in electrical activity of buccinator muscle was evaluated and monitored using electromyography (EMG) apparatus [Figure 3]. Border molding was done using low fusing green stick (pinnacle tracing sticks); Dental Products of India and the final impression was made using polyvinylsiloxane elastomeric impression material with ULF-TENS still in function at same frequency and amplitude of electric current [Figure 4]. Jaw relations were recorded and transferred to Hanau Wide Vue (Whipmix USA) semi-adjustable articulator. Teeth were arranged in bilateral balanced occlusion, and try-in was done [Figure 5]. Cameo surface on the buccal aspect was re-recorded using ULF TENS at the same amplitude, frequency, mode, and duration of stimulation as used for the definitive impression with due precautions. Tray adhesive was applied over the cameo surface, and polyvinylsiloxane elastomeric material (Virtual; Monophase) was applied over the labial and buccal surface of the maxillary denture with the ULF-TENS unit still in function. Maxillary denture base was left in position with no functional movements till the material sets. Similar procedure was performed for mandibular denture [Figure 6]. Cameo surfaces on the palatal side of the maxillary prosthesis and lingual side of the mandibular prosthesis were recorded with same material asking the patient to perform various functional movements such as swallowing and pronouncing linguo palatal and linguo velar sounds. The prosthesis was acrylized, and the finished prosthesis was delivered [Figure 7]. The precaution includes placing the electrodes on healthy skin under the supervision of the clinician. The ULF TENS application was done in the presence of neurologist for supervision of EMG recording during the ULF-TENS application.{Figure 2}{Figure 3}{Figure 4}{Figure 5}{Figure 6}{Figure 7}


TENS is a therapeutic modality, mainly used for the management of musculoskeletal pain, as it promotes analgesic effects. Conventional TENS works through gate control theory.[8] Neuromuscular TENS or ULF-TENS was proposed initially by Jankelson in 1969 and is used by various therapeutic strategies.[9] ULF-TENS has been opined to act through dromic and antidromic methods on the muscular component to cause contraction of VIIth and the Vth pair of cranial nerves, resulting in relaxation of the masticatory musculature.[10]

ULF-TENS has various advantages when compared to conventional TENS, its lesser noninvasive, negligible side effects, not technique sensitive (most often they are self-administered by the patient after due training) and are relatively easier to use.

Clinically, the application of TENS utilizes two levels of frequencies, i.e., low frequency and high frequency. In low-frequency TENS, frequency of stimulation is <10 Hz, whereas in high-frequency TENS, it is >50 Hz. The term “ULF” is used when frequency of <4 Hz is used for stimulation.[11]

The two terminals of each electrode could be placed on either side of the midline, one in preauricular region, and another in the posterior triangular region of the neck. The terminal in the preauricular region is responsible for the stimulation of facial nerve supplying motor neurons to the buccinators, orbicularis oris, levator labii superioris, and levator labii inferioris. The posterior triangle contains the cranial accessory nerve which supplies palatoglossus muscle through the vagus nerve. Stimulation of this muscle is responsible for raising the tongue against the posterior extent of the prosthesis. Frequency of delivery of current is to be adjusted to 2–4 Hz and amplitude and to be raised from 0 to 4 depending on subjective symptoms and tolerating capacity of the individual. TENS can be applied for a total 40 min, whereas muscle twitching begins at 10–12 min.[12] No functional or manual movements are to be performed, however, recording material, i.e., polyvinylsiloxane monophase, gets adapted to the cameo surface due to relaxation of the surrounding musculature. Disadvantages include that it can only be used for recording the labial and buccal aspect of cameo surface and cannot be used for palatal and lingual aspect of the maxillary and mandibular prosthesis, respectively.

Various neuromuscular diseases that affect the orofacial muscles and in turn affect the activity of TMJ include cerebrovascular accident, Parkinson's disease, multiple sclerosis, Huntington's disease, and Creutzfeldt–Jakob disease. ULF-TENS (<4 Hz) application results in muscle relaxation along with bilateral muscular balance and helped inaccurate recording of the cameo surface. Studies done by various authors prove that the application of ULF-TENS causes reduction in EMG activity of the masticatory muscles.[13]

However, some authors do advise caution in the use of ULF-TENS in the cases, in which effects of its administration could not be measured with electromyographic analysis. If terminals are placed on the carotid sinus, it can result in vagal bradycardia and can lead to a life-threatening situation. Furthermore, the application of TENS is contraindicated in patients having pacemakers, cardioverter-defibrillator, or pregnant women.


A successful complete denture prosthesis can be attained in patients with poor neuromuscular incoordination by accurately recording the cameo surface of complete denture that aids in improving retention and stability of the denture. Border molding and recording cameo surface using ULF TENS is an effective method that helps in the physiological adaptation of the prosthesis to orofacial musculature. Application of ULF-TENS in complete denture fabrication immensely improved patient satisfaction and acceptability due to the improved fit of the prosthesis.

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Conflicts of interest

There are no conflicts of interest.


1Devaki VN, Manonmani P, Balu K, Aravind RJ. Clinical management of highly resorbed mandibular ridge without fibrous tissue. J Pharm Bioallied Sci 2012;4:S149-52.
2Malachias A, Paranhos Hde F, da Silva CH, Muglia VA, Moreto C. Modified functional impression technique for complete dentures. Braz Dent J 2005;16:135-9.
3Ohkubo C, Shimpo H, Tokue A, Park EJ, Kim TH. Complete denture fabrication using piezography and CAD-CAM: A clinical report. J Prosthet Dent 2018;119:334-8.
4Bhattacharyya J, Goel P, Ghosh S, Das S. Piezography: An innovative technique in complete denture fabrication. J Contemp Dent 2012;2:109-13.
5Bulbule NS, Shah J, Kulkarni S, Kakade D. Rehabilitation of a completely edentulous patient using TENS to record functional borders and cheek plumpers for esthetics. Int J Prosthodont Rest Dent 2013; 3:78-82.
6Koli D, Nanda A, Kaur H, Verma M, Jain C. Cameo surface recording in complete denture fabrication using transcutaneous electrical nerve stimulation: A clinical report. J Prosthet Dent 2017;118:127-30.
7McGarry TJ, Nimmo A, Skiba JF, Ahlstrom RH, Smith CR, Koumjian JH. Classification system for complete edentulism. The American College of Prosthodontics. J Prosthodont 1999;8:27-39.
8Black RR. Use of transcutaneous electrical nerve stimulation in dentistry. J Am Dent Assoc 1986;113:649-52.
9Jankelson B, Sparks S, Crane PF, Radke JC. Neural conduction of the myo-monitor stimulus: A quantitative analysis. J Prosthet Dent 1975;34:245-53.
10Beresin VE, Schiesser FJ. The neutral zone in complete dentures. J Prosthet Dent 1976;36:356-67.
11Chipaila N, Sgolastra F, Spadaro A, Pietropaoli D, Masci C, Cattaneo R, et al. The effects of ULF-TENS stimulation on gnathology: The state of the art. Cranio 2014;32:118-30.
12Esclassan R, Rumerio A, Monsarrat P, Combadazou JC, Champion J, Destruhaut F, et al. Optimal duration of ultra low frequency-transcutaneous electrical nerve stimulation (ULF-TENS) therapy for muscular relaxation in neuromuscular occlusion: A preliminary clinical study. Cranio 2017;35:175-9.
13Kamyszek G, Ketcham R, Garcia R Jr, Radke J. Electromyographic evidence of reduced muscle activity when ULF-TENS is applied to the Vth and VIIth cranial nerves. Cranio 2001;19:162-8.