Five year clinical outcomes and evaluation following implantation of the Oticon™ wide bone anchored hearing system in 47 children

Provision of bone conduction hearing implants in England in adults and children: a review of Hospital Episode Statistics data 2012-2021

OBJECTIVE

Bone conduction hearing implants are a well-established method of hearing rehabilitation in children and adults. This study aimed to review any changes in provision in England.

METHODS

The total number of bone conduction hearing implantations performed was analysed from 2012 to 2021 utilising Hospital Episode Statistics data for England.

RESULTS

The total number of procedures has increased by 58 per cent. One-stage bone conduction hearing implantations in adults accounts for the largest proportion of this increase (93 per cent of the total). The number performed in children has remained stable and accounts for 73 per cent (n = 433) of all two-stage procedures.

CONCLUSION

The data show that bone conduction hearing implant surgery is becoming increasingly popular, particularly in adults. This has correlated with the increase in availability, national recommendations and choice of devices.

Paediatric percutaneous bone anchored hearing aid implant failures: Comparing the experience of a tertiary centre with a systematic review of the literature and meta-analysis

BACKGROUND

Despite the proven audiological benefits of Percutaneous Bone Anchored Hearing Aids (BAHAs) in paediatric patients with conductive or mixed hearing loss, their adoption has been limited due to concerns over implant failure and associated complications. This paper conducts a systematic review and meta-analysis to assess the prevalence of implant failure in paediatric populations, combined with a case series from our tertiary referral centre.

METHODS

A comprehensive literature search identified 562 articles, from which 34 were included in the review, covering 1599 implants in 1285 patients. Our retrospective case series included consecutive patients from our tertiary referral centre who underwent percutaneous BAHA implantation from 2003-2019.

RESULTS

Meta-analysis revealed an overall implant failure rate of 11%, predominantly attributed to traumatic extrusion. Our retrospective case series comprised 104 implantations in 76 patients, with a 4.8% failure rate.

DISCUSSION

Factors contributing to the lower-than-expected failure rates in the case series likely included consistent use of 4 mm fixtures from a single manufacturer and older age at implantation. The study underscores the need for standardised reporting formats in bone conduction implants research, given the systematic review's limitations in study design heterogeneity, especially with the expected rise in the adoption of novel active devices.

Long-term osseointegration of laser-ablated hearing implants in sheep cranial bone

Osseointegration, the ability for an implant to be anchored in bone tissue with direct bone-implant contact and allowing for continuous adaptive remodelling, is clinically used in different reconstructive fields, such as dentistry, orthopedics and otology. The latter uses a bone conducting sound processor connected to a skin-penetrating abutment that is mounted on a titanium implant placed in the temporal bone, thereby acting as a path for transmission of the vibrations generated by the sound processor. The success of the treatment relies on bone healing and osseointegration, which could be improved by surface modifications. The aim of this study was to evaluate the long-term osseointegration in a sheep skull model and compare a laser-ablated implant surface with a machined implant. Commercially available 4 mm titanium implants, either with a machined (Wide Ponto) or a laser-ablated surface (Ponto BHX, Oticon Medical, Sweden), were used in the current study. The surfaces were evaluated by scanning electron microscopy. The implantation was performed with a full soft tissue flap and the osteotomy was prepared using the MIPS drill kit (Oticon Medical, Sweden) prior to installation of the implants in the frontal bone of eight female sheep. After five months, biopsies including the implant and surrounding bone tissue obtained, processed and analysed using histology, histomorphometry, scanning electron microscopy and Raman spectroscopy. The animals healed well, without signs of adverse events. Histomorphometry showed a large amount of bone tissue around both implant types, with 75% of the threaded area occupied by bone for both implant types. A large amount of bone-implant contact was observed for both implant types, with 67%–71% of the surface covered by bone. Both implant types were surrounded by mature remodelled lamellar bone with high mineral content, corroborating the histological observations. The current results show that the laser-ablated surface induces healing similar to the well-known clinically used machined surface in ovine cranial bone. In conclusion, the present long-term experimental results indicate that a laser-ablated implant performs equally well as a clinically used implant with a machined surface. This, together with previously reported, improved early biomechanical anchorage, suggests future, safe and efficient clinical potential.

Clinical Evaluation of a Novel Laser-Ablated Titanium Implant System for Bone Anchored Hearing Systems in a Pediatric Population and the Relationship of Resonance Frequency Analysis With Implant Survival

OBJECTIVE

To evaluate the clinical outcomes of pediatric patients implanted a novel 4.5 mm wide laser ablated titanium bone anchored implant system and to evaluate the implant stability over the first 12-month period.

STUDY DESIGN

A prospective, single-subject, repeated measure, cohort study. Participants served as their own controls.

SETTING

Community and tertiary referral hospital pediatric assessment center.

PATIENTS

A total of 115 consecutive pediatric patients aged 4 to 15 years were implanted with 176 laser ablated titanium bone anchored implants from January 2016 to January 2019.

MAIN OUTCOME MEASURE

Clinical outcomes, implant failure rates, and post implantation implant stability quotient (ISQ) scores were studied over the first 12-month period. Data were analyzed for statistical significance through mixed effect modeling, with the significance level p = 0.01.

RESULTS

A median 12-month survival of 96.6% was observed. Six implants (3.5%) were lost in total, one of these (0.6%) was lost due to trauma. Adverse skin reactions (Holgers grade 2-4) were observed in 4.4% of all postoperative visits, occurring in 22 individuals (19.1%). Neither the ISQ high (ISQH) nor ISQ low (ISQL) values increased significantly between the stage 1 and 2 surgeries. In contrast, the ISQ results, irrespective of abutment size, demonstrated an increasing trend from 49.1 to 57 over the 12 months review period. A statistically significant change was only demonstrated from the 3 months follow up onwards.

CONCLUSION

The use of 4.5 mm wide laser-ablated titanium bone anchored hearing implants resulted in superior survival rates and excellent clinical outcomes compared with previous implant systems.

Clinical evaluation and resonance frequency analysis of laser-ablated titanium bone-anchored hearing implant system in children with Down Syndrome

OBJECTIVES

To evaluate complication rates and resonance frequency analysis (RFA) of the stability of a new laser-ablated titanium Bone Anchored hearing Implant system in children with Down syndrome.

METHODS

A prospective, single-subject, repeat measure, cohort study in which each participant served as their own control. Consecutive paediatric patients 4yrs- 15 years old, with a primary diagnosis of Down syndrome (trisomy 21) were implanted between January 2015-January 2020 with BHX Oticon wide implants. Evaluation of soft tissue reactions, fixture failure rates and post implantation Implant stability Quotient (ISQ) at both fixtures and abutment levels were studied over a 12-month period. Data was analysed for statistical significance through mixed effect modelling with significance set at p = 0.01.

RESULTS

31 consecutive paediatric patients with a diagnosis of Down syndrome were implanted with 43 Ponto BHX Oticon™ implant system. Twelve children had bilateral implants and nineteen were unilateral. Over the 12 month follow up 2 fixtures (4.6%) were lost, and adverse skin reactions (Holgers >2) were recorded in 3.2% of all clinical reviews. Implant level stability quotient showed no statically significant change between first and second stage 71.1-71.7. Abutment level ISQ increased from 46.2 to 56.7 p = 0.0001 at the 12-month review point as compared to that recorded at loading.

CONCLUSION

Implant survival and adverse skin reactions were found to be in keeping with those in published literature and much improved compared to previous implant systems placed at this centre. Although abutment level ISQ showed an increase over the review period no correlation between this and implant loss can be concluded.