LinguaGraph

Yes. LinguaGraph is widely used with children, including in school-based programmes, university clinics, and cleft palate services. The biofeedback games, regional colour coding, and the 3D tongue model make it particularly engaging and intuitive for younger speakers. However, several factors should be considered when using EPG with children:

Minimum age — The EPG palate clips to the upper teeth and requires a stable dentition for accurate fitting and reliable retention. Deciduous dentition is generally established by around 3.5 years and stable until approximately 6 years, making 6 years a practical minimum age for most speakers. Children in the mixed dentition stage (6–13 years) may require palate alteration or replacement as their dentition changes.

Cognitive ability — EPG requires the speaker to understand the relationship between tongue placement and the visual display. A certain level of cognitive ability is a prerequisite for effective use, as noted in the Cochrane review of EPG therapy (Lee et al., 2009).

Acclimatisation — A practice palate, which contains no electrodes or lead out wires, can be used to help speakers adjust to wearing the EPG palate before sessions begin. Increased saliva production is common initially and usually settles with acclimatisation.

A practice palate is a custom-made palate that contains no electrodes or lead-out wires. It is used to help speakers acclimatise to wearing an EPG palate before sessions begin.

Wearing a practice palate allows the speaker to adjust to the sensation of the palate in the mouth, including the increased saliva production that is common initially. Acclimatisation with a practice palate can reduce the time needed to settle into EPG sessions and reduces the incidence of false contacts caused by excess saliva.

Contact us for further information on practice palates.

Yes — each speaker requires their own custom-made artificial palate. The palate is moulded to fit the individual speaker's hard palate and clips to their upper teeth. Because palate shape varies significantly between individuals, a standard or universal palate is not available.

EPG palates are manufactured from a plaster model of the speaker's upper palate and teeth. A qualified dentist takes an impression using high quality alginate — note that the requirements differ from a general dental impression, as the impression must extend to include the gum area immediately behind the posterior molars to accommodate the lead-out wires. The plaster model is then sent to the laboratory for palate manufacture. Alternatively, an intraoral 3D scan can be used to produce a 3D printed model, which is sent to the laboratory in place of a traditional plaster impression.

EPG palates typically take 2–3 weeks to manufacture from receipt of the plaster model at the laboratory. It is recommended that a photograph of the plaster model is emailed to enquiries@rose-medical.com before sending, to confirm the model is suitable for palate manufacture.

Contact us for further guidance on the impression and plaster model requirements.

Yes. An intraoral 3D scanner can be used to capture a digital record of the speaker's upper palate and teeth, removing the need for a traditional alginate impression. The digital file is used to produce a 3D printed model, which is then sent to the laboratory in place of a traditional plaster cast.

Note that the dental laboratory cannot currently accept digital files directly — a physical model is still required. However, a 3D printed model produced from an intraoral scan is a suitable alternative to a plaster cast and may be more convenient in settings where access to a dentist for impression-taking is limited.

Contact us to discuss this workflow before proceeding.

The EPG palate kit enables an orthodontic technologist to manufacture an EPG palate locally. Each kit contains:

• 62 silver electrodes with attached leads (spare electrodes included)
• EPG connector board
• EPG connector board cover
• Heat shrink tubing
• Instruction manual

The palate kit is particularly useful for institutions with access to an in-house orthodontic technologist, or in countries where shipping time and costs make overseas palate manufacture impractical.

EPG palate kits are available to order from icSpeech. Contact us for further information.

To clean the EPG palate after use, rinse in warm water. If necessary, clean gently with a soft toothbrush and mild detergent, then wipe dry with a soft tissue. Avoid getting the palate connector wet. Always place the palate back on the plaster cast when not in use, and avoid subjecting the wires to undue tension or excessive coiling.

Note that eating salty or sugary foods immediately before wearing the palate can cause false contacts. In these circumstances the speaker should rinse their mouth with water before fitting the palate.

For specific decontamination guidance relevant to your clinical or institutional setting, please contact us.

False contacts are electrodes that appear to register tongue contact even though the tongue is not actually touching that part of the palate. They occur in two main forms:

• Flickering contacts — individual electrodes that randomly activate and deactivate, often rapidly. Most common during the initial acclimatisation period or when the speaker has eaten salty or sugary foods before fitting the palate.
• Sticky contacts — a cluster of adjacent electrodes that remain persistently active regardless of tongue position. Caused by excess saliva bridging a group of electrodes rather than activating them intermittently.

How to minimise false contacts

• Allow at least 15 minutes acclimatisation time before a session
• Ask the speaker to rinse their mouth with water before fitting the palate
• Use a practice palate to aid acclimatisation
• Frequently remove the palate and wipe with a paper tissue
• Avoid eating salty or sugary foods immediately before fitting the palate
• Ensure the sensitivity is correctly adjusted using the sensitivity control on the LinguaGraph unit
• Increase the position of the Remove false contacts slider in the software settings

Electropalatography and ultrasound tongue imaging (UTI) are complementary rather than competing techniques — each captures articulatory information that the other cannot.

EPG measures exactly where and when the tongue contacts the hard palate across 62 electrode positions. It provides precise, quantifiable data on tongue-palate contact patterns, but cannot show tongue shape or movement in areas away from the palate.

Ultrasound shows the shape and movement of the tongue body in real time, including regions that do not contact the palate. However, ultrasound cannot directly measure tongue-palate contact.

A key advantage of EPG is its ability to reveal tongue–palate contact patterns that cannot be directly observed or reliably identified through perceptual analysis alone. Research has shown that lateral fricatives, for example, are easily visualised by EPG but not by midsagittal ultrasound (Cleland et al., 2025).

icSpeech Professional Edition and LinguaGraph can be used simultaneously with ultrasound tongue imaging, allowing both contact patterns and tongue shape to be recorded in a single session.

Yes. LinguaGraph has been used in peer-reviewed research published in international journals, including studies in phonetics, cleft palate speech, verbal dyspraxia, cerebral palsy, and cochlear implant research. When citing LinguaGraph in publications, please reference it as:

LinguaGraph EPG System, icSpeech, Rose Medical Solutions Ltd., Canterbury, UK.

A list of publications featuring icSpeech technology is available on our publications page.

LinguaView, LinguaView 3D, and icSpeech Professional Edition currently support Windows 10 and Windows 11 only. The LinguaGraph hardware uses a standard USB connection and is not platform-restricted, but the software requires Windows. Users working in Mac environments may wish to run Windows via Boot Camp or a virtual machine. Please contact us to discuss your setup.

Yes. LinguaGraph uses the Reading EPG palate design, which is the same design used by WinEPG (Articulate Instruments). Palates manufactured for WinEPG are therefore compatible with LinguaGraph.

Note that Articulate Instruments ceased EPG production in 2013. Existing WinEPG users looking to replace or upgrade their system may wish to consider LinguaGraph as a compatible alternative. Contact us to discuss compatibility with your existing palates.

LinguaGraph connects to a local Windows computer and captures EPG data locally. A speech professional, trained assistant, or researcher can operate the system with the speaker present, while a remote clinician or researcher observes via video call. The EPG display can be shared in real time using screen sharing on any standard videoconferencing platform such as Zoom or Microsoft Teams, allowing a remote clinician or researcher to observe the session live. Recorded EPG data can also be exported and shared for offline review.

Contact us to discuss remote working.

Yes. icSpeech supplies universities, hospitals, and research institutions globally. We provide formal quotations suitable for institutional procurement processes and grant applications. Please use the Get quote form and indicate your institution type. We will respond promptly with appropriate pricing and documentation.

LinguaGraph is compatible with three software options:

• LinguaView — entry-level software for real-time EPG display and recording
• LinguaView 3D — adds a 3D animated tongue-palate model with 360° rotation
• icSpeech Professional Edition — full multiparameter speech analysis platform with EPG displays, biofeedback games, lingual parameters, and simultaneous recording of ultrasound, EGG, nasometry, airflow and video

Developers can also access the LinguaGraph SDK to build custom applications. Contact us for guidance on choosing the right software for your requirements.

Raw EPG data can be exported to CSV (comma-separated values) format using icSpeech Professional Edition. Each row in the CSV file represents an EPG frame, stored as a 64-bit hexadecimal value. A bitmap lookup table is used to extract the individual electrode contact states from each frame.

CSV files can be opened in standard data analysis applications including Microsoft Excel, MATLAB, R, and Python, making the data readily accessible for offline analysis and research.

Contact us for further information on EPG data export, including documentation on the CSV file format.