This study is performed to collect safety and performance data supporting the use of the Sentio system in children below 12 years of age. The system is currently available on the market for patients 12 years and above. It is a prospective study conducted at eight European hospitals, aiming to treat 50 patients with a hearing loss than would benefit from treatment with a bone-anchored hearing system (BAHS). The primary objective of the study is to demonstrate that the Sentio system improves the hearing on the implanted ear, compared with the unaided situation.

This study is performed to collect safety and performance data supporting the use of the Sentio system in children below 12 years of age. The system is currently available on the market for patients 12 years and above. It is a prospective, multicentre study sponsored by Oticon Medical AB, which will be conducted at eight hospitals across Europe (UK, Spain and the Netherlands). A total of 50 patients with a hearing loss than would benefit from treatment with a bone-anchored hearing system (BAHS) will be included. Participation is voluntary and the decision to participate must be well-founded and well informed.

The Sentio system is a transcutaneous bone conduction hearing system (an implant and an external sound processor) for individuals with certain types of hearing losses. The implant is implanted into the bone behind the ear (mastoid and temporal bone area). After a period of skin healing, a sound processor which transmits sound waves to the implant can be magnetically attached. The implant transforms the sound waves to vibrations, which are then transmitted to the inner ear via the bone. The primary objective of the study is to demonstrate that the Sentio system improves the hearing on the implanted ear, compared with the unaided situation.

The study includes eight study visits; one before surgery, the surgery visit, and six follow-up visits, with the last visit taking place 12 months after surgery.

Inclusion Criteria:

1. Signed Informed Consent Form (depending on age of child, signed by parent or legal guardian and child)

2. Subject aged 3 to 11 years

3. Subject with:

   3.1 conductive or mixed hearing losses with pure tone average (PTA) bone conduction (BC) threshold (measured at 0.5, 1, 2 and 3 kHz) of the indicated ear better than or equal to 45 dB HL.

   3.2 OR subject who has a profound sensorineural hearing loss in one ear and normal hearing in the opposite ear (i.e. SSD). The pure tone average (PTA) air conduction (AC) threshold of the hearing ear should then be better than or equal to 20 dB HL (measured at 0.5, 1, 2 and 3 kHz) 3.3 OR subject indicated for an air-conduction contralateral routing of signals (AC CROS) hearing aid, but who for some reason cannot or will not use an AC CROS.

4. Subject and parent or legal guardian have the ability and willingness to comply with investigational procedures/ requirements, as determined by the investigator.

5. Subject with prior experience of amplified sound through a properly fitted hearing aid, a CROS device, or a non-surgical bone anchored solution (e.g. softband).

6. For subject with conductive or mixed hearing losses, ensure sufficient air bone gap (ABG) at the ear to be implanted.

7. Sufficient bone quality/quantity/depth or skull size for implantation of a Sentio Ti implant as assessed according to clinical practice.

Exclusion Criteria:

1. Medical condition that contraindicates implant surgery or anesthesia as judged by the investigator.
2. Untreated ongoing middle ear infection at the time of surgery.
3. Known or suspected contact allergy to silicone or other material used in the Sentio system.
4. Known condition that could jeopardize wound healing and skin condition, e.g. uncontrolled diabetes over time, as judged by the investigator.
5. Known skin or scalp conditions that may preclude attachment or interfere with the usage of the sound processor.
6. Evidence of conditions that would prevent good speech recognition potential as determined by good clinical judgment.
7. Any other known condition that the investigator determines could interfere with compliance or investigation assessments.
8. Use of ototoxic drugs that could be harmful to the hearing, as judged by the investigator.
9. Subject that has received radiotherapy in the area of implantation or is planned for such radiotherapy or similar during the investigation period.
10. For bilateral asymmetric candidates, subject already treated with a bone-anchored hearing solution on the side with the best bone conduction thresholds.
11. Known chronic or non-revisable vestibular or balance disorder.
12. Known abnormally progressive hearing loss.
13. Currently participating, or participated within the last 30 days, in another clinical investigation involving an investigational drug or device that could impact the safety or effectiveness of the Sentio system as determined by the investigator.
14. Use of active implantable or body worn device that for medical reasons cannot be removed or discontinued, such as CSF shunts, implantable cardiac pacemakers, defibrillators, or neurostimulators.
15. Known need for frequent MRI investigations for follow-up of other diseases.
16. Any subject that according to the Declaration of Helsinki is deemed unsuitable for investigation enrolment.