The Safety of S53P4 Bioactive Glass for Mastoid Obliteration

Study Overview
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Brief Summary
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In recent years, mastoid obliteration (MO) after mastoidectomy has gained popularity. However, the choice for obliteration material has been a point of discussion. Autologous materials have the advantage of being freely available without cost.Synthetic materials on the other hand have unlimited supply, hold volume over time and have no risk of donor site morbidity. Comparative studies between materials are rare and the few available were unable to ascertain superiority. Our hospital has been utilizing the same material for obliteration since 2011: S53P4 bioactive glass (BAG). It since has become our main operating procedure to obliterate the mastoid cavity with BAG granules following both canal wall up (CWU) and canal wall down (CWD) mastoidectomy. This bioactive glass has several important characteristics, such as the retaining of volume over time and antibacterial properties. An important factor when selecting obliteration material is safety. Data on this was reported in several studies, but unfortunately these studies only investigated short-term safety in small and selected cohorts of patients, often without comparison. Additionally, large studies with extensive follow-up are necessary to detect rare complications and long-term pitfalls. Therefore, the aim of this study is to determine the safety of BAG in a cohort that encompasses all cases that underwent CWU+MO and CWD+MO in our institute and compare these results to a non-obliteration cohort. The main outcomes are short- and long-term safety, as indicated by surgical complications in the first year following surgery and revision surgeries during follow-up, respectively. We compare the obliteration cohort to the non-obliteration cohort, hypothesizing that obliteration results in a comparable or lower rate of complications and revision surgeries

Official Title
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The Short- and Long-Term Safety of S53P4 Bioactive Glass for Mastoid Obliteration: a Retrospective Comparative Study

Conditions
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Mastoid Cavity

Intervention / Treatment
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* Device: S53P4 Bioactive glass


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Canal wall up or canal wall down mastoidectomy Operated between 2010 and 2022 All indications are included Exclusion Criteria: Other surgical techniques, such as subtotal petrosectomy
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients that underwent mastoidectomy + mastoid obliteration using bioactive glass<br>This is the intervention group, consisting of patients that have underwent either canal wall up or canal wall down mastoidectomy followed by obliteration of the mastoid cavity using S53P4 bioactive glass for any indication | Device: S53P4 Bioactive glass<br>* Following mastoidectomy, the mastoid cavity, and if the ossicular chain has been removed the epitympanum as well, are obliterated using S53P4 bioactive glass. The bioactive glass is mixed with saline and administered to the cavity, ensuring a tight fit.<br>|
| Patients that underwent mastoidectomy alone<br>This is the control group, consisting of patients that have underwent either canal wall up or canal wall down mastoidectomy without mastoid obliteration for any indication | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of patients with postoperative surgical complications in the first year following surgery | Complications that occured within the first year following surgery We compare the obliteration cohort to the non-obliterative cohort | First year following surgery | 
| The number of patients which require revision surgery during follow-up | Revision surgeries performed during follow-up due to problems with the obliteration | At 3-, 5- and 8-years postoperatively |