Earmould Selection

1. Earmould Selection Sue Falkingham Audiologist/Hearing Therapist/RHAD

2. Outline • Available choices • Top 10 earmould selections • Evidence based decision making • Improvements • Cases

3. Material Selections

4. Wide variety of materials available • Biopor • Moloplast • Microflex • Non Cadium • Acrylon • Gold • Platinum • Silver • PVC • Hard Acrylic • Soft Acrylic • Audiflex • Thermotec • Silastic • Micropor • Vinyl • Bioplast • COE

5. 88% of production 13 moulds

6. Making Choices

8. Evidence • Limited research into earmould technology • Late 70s and early 80s papers in Scandinavian audiology on hard vs soft materials • Research into manufacturing techniques in 1990s • Small research studies in later years but less interest since RIC and open fit technology took over the world!

9. Evidence and experience

10. Hard vs. soft • Hard materials are not suitable for paediatrics • Softer the better for power products • Softer moulds are more comfortable • If someone is allergic to a mould we swap to a soft material • Soft is soft so we just use a 2108 B • Hard with a soft tip is a great option for all

12. Hard materials are not suitable for paediatrics • If a patient is prone to bumps or falls then there is an argument that hard materials will shatter if struck hard and in the right (wrong) way. • Hard materials are less forgiving in a rapidly growing ear as they are prone to slit leaks if the ear shape changes • Cosmetically hard materials are superior • Less maintenance • More ability to drill and sculpt Maybe

13. Softer the better for power products • The impression is key in fit not the material • Excellent feedback managers in hearing aids effectively reduce issues • Soft acrylic is porous and shrinks in as little as 12 months requiring regular replacement to keep it tight fitting • No evidence that soft gives a better fit Myth

14. Summary of the evidence • In general, all studies indicate that earmould fit and acoustic seal are not enhanced by the use of soft materials. • Rather, the accuracy of the earmould fitting is determined by the impression-taking technique. • The viscosity of the impression material. • The parameters of the molding process. Earmolds: Are soft materials superior? Pirzanski, Chester Hearing Jounal July 2001

15. Softer Moulds are more comfortable • No evidence for soft being more comfortable • Comfort is determined by flexibility at the interface between the mould and the ear. If the ear is flexible the hard material will still be comfortable. • We don’t tend to place earmoulds in to the bony portion of the canal where there is little flexibility • If you are doing a deep mould you might want a soft material as the ear will not be flexible. Myth

16. If someone has an allergic reaction to a mould we swap to a soft mould • True contact dermatitis is rare • Mainly sweat reactions from having ears full shell moulds • Open up the earpiece to make it fill less of the ear • Make the earmould easier to clean • Use a laser printed mould Myth

17. Soft is soft Myth

18. Soft is soft • Soft materials come in a range of shore values • Routinely 25, 40 and 60 • Affects texture and ease of insertion • Use the right shore value for your patient • Permanently elastic • Does not harden or discolour

19. 25 shore rating - soft • Good for very fragile ears • Needs thick tubing • Tubing easily dislodged when pulled • Venting difficult to keep open • Very hard to adjust in clinics • Forgiving around ear abnormalities lumps and bumps

20. 40 shore rating - mid • Easier to vent and shape than soft • Maybe similar to older materials • Default build in most places • Soft but not squishy • Takes different tubing thicknesses

21. 60 shore rating - firm • Hardest of the soft materials • Good for those with dexterity issues • Easier to adjust, vent and carve makes good skeletons • Tubing more easily retained • Biopor in 60 Shore is a direct replacement for soft acrylic moulds

22. Hard with a soft tip is a great option for all • Cosmetics are better when in the ear as hard acrylic is permanently clear • Tube retention is good • Cleaning not as easy as all hard • No low allergy properties • Unnecessary joining of two materials – leaving a potential break point/weakness • Tip discolours • Shrinks over 12 months Myth

24. My Favourite Earmould Modification • Power Vent • Long thin vent that allows ventilation but no feedback path • Hard printed moulds only • Runs all the way round the concha bowl

25. Style

26. Consider the customer • What can they see? • What can they feel? • How closed does the mould have to be to prevent feedback • Any ear abnormalities to account for • Ease of maintenance • Way they remove the mould

27. Skeleton • Great choice • Not as sweaty • Easy to hold and orientate for insertion • Could be a but fragile for some • Retains in most ears • Don’t forget semi-skeleton

28. Canal and half shell • If the customer can’t get a mould under helix • Needs a good canal depth or can slip out • Cosmetically good • Could use a canal lock for retention • Can be helpful for dexterity issues

29. Shell • Good sealing properties • Blocks the whole ear • Often easy to get a grip of if dexterity issues • Can cause sweat reactions • Available in all material types

30. Thanks for listening