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Harder, Stronger, Clearer

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Harder, Stronger, Clearer Harder, stronger, clearer. Presenting new technologies and advancement in spectacle lens materials CET approved C-36183 For Trivex Lens Specialist Practices, UK A live webinar presented by the ABDO College in Canterbury, UK in association with PPG Optical Materials Course Outline Kevin Gutsell FBDO (Hons) SLD ABDO • Introduction • Timeline of lens material technology developments • Overview of lens materials technologies • Lens material properties and patient benefits Dora Plisic Trade Manager • Developments in lens design and coating PPG Optical Materials technologies • British consumer trends • Summary and Q&A Keith Cross (guest speaker) Director, Rx Technologies, R&D PPG Optical Materials How has technology overall evolved over the last 60 years? Technology Evolution: The Telephone 3G: 1st country to launch - UK 1937 1977 1983 1991 2001 2007 2G: 1st GSM network Technology Evolution: The distribution model New contract is signed 2 years contract with mobile phone network providers New mobile phone platform is provided How has technology in the ophthalmic lenses evolved over the last 60 years? Anatomy of an ophthalmic lens Patient comfort Technology Developments in Lens Materials 1950’s CR-39® lens development begins 1970’s FDA impact test regulation increases use of CR-39® lenses 1980’s Polycarbonate lenses become more popular in U.S. 2000’s Trivex® lenses introduced Prescription Distribution 85% of Rx’s in Western Countries are in the range of +/-3.00 D Technology Developments in Lens Materials 1980’s Mid Index (1.56, 1.60) lens development begings 1990’s Additional developments in high index lenses (1.60, 1.67) 2000’s Very high index lenses development (1.74) Prescription Distribution In the Pacific region, prescriptions are higher from +/-3.00 to +/-6.00 D What is a lens material made from? Lens material overview: CR-39® Chemistry Structure •Organic (Carbon-based) •Thermoset •Properties: •Highly cross-linked • Impact resistance better than glass • High resistance to heat • High Abbe number • Lighter than glass Lens material overview: Polycarbonate Chemistry: Structure: •Organic (Carbon-based) •Thermoplastic •Properties: •Long independent chains • High Impact resistance •Not cross-linked from 90° angle only • Low resistance to heat • Low Abbe value Lens material overview: High Index Chemistry: Structure: •Organic (Carbon-based) •Thermoset • Urethane backbone with added sulfur to •Highly cross-linked increase refractive index •1.60: approximately 30% sulphur •1.67: approximately 40% sulphur •1.74: approximately 60% sulphur •Properties: • Thinner lens • Lower optical performance • Higher density Lens material overview: Trivex® Chemistry: •Organic (Carbon-based) •Urethane backbone enriched with Urea (Nitrogen) •Properties: • High Impact resistance • High Resistance to heat • High Optical performance Structure: • Lightest prescription lens •“Quasi-Thermoset” material •Slightly cross-linked long chain structure How does this translate to the overall performance properties of the lens? Patient comfort Clear Vision: Abbe Number 60 CR-39 (58) 50 Trivex (45) 1.60 40 (40) 1.74 1.67 Polycarbonate (33) (31) 30 (30) Clearest 17 The Abbe Number (V-value) is a measure of the dispersion exhibited by the material. The higher the Abbe Number the more accurately a lens aligns the spectrum of light waves that pass through it. Lightweight: Density 1.10 Trivex 1.11 g/cm3 Polycarbonate 1.20 1.20 g/cm3 1.60 1.30 CR-39 1.30 g/cm3 1.31 g/cm3 1.67 1.36 g/cm3 1.40 1.74 1.47 g/cm3 1.50 Heaviest Lightest Density expresses the weight of the material. The lower the density, the lighter and more comfortable the lens will be for the patient. Thin: Refractive Index 1.75 High Index 1.74 1.70 High Index 1.67 1.65 1.60 Mid Index 1.60 Polycarbonate 1.59 1.55 Trivex 1.53 1.50 CR-39 1.50 Refractive index is the ratio of the velocity of light in vacuum to that in the material. It tells us how fast light travels through a material. Eye Health: UV Protection 400 High Index 1.74 Trivex High Index 1.53 1.67 390 Polycarbonate 1.59 380 Mid Index 1.60 CR-39 350 1.50 UV cut- off (nm) Ultra violet (UV) radiation is known to cause skin cancer and protection of the eyes from UVA and UVB is considered essential for every patient. Safety & Protection: Durability >700 Polycarbonate Trivex >700 in-lbf >700 in-lbf 300 200 100 1.60 1.67 53 in-lb 56 in-lb CR-39 f f 31 in-lbf 0 21 Brittle Resilient How do these features translate into patient benefits? Patient Comfort •80 percent of what children learn in their first 12 years comes through their eyes • 64.5% of adults are physically active • Seniors have aging and thinner skin on their nose • Rimless frames require durable lens that wont break or crack • UV levels are three times greater in summer than winter • 20% of cataract cases are due to UV rays • The most of UV damages to eye happen prior to the age of 12 as the eye is not mature and fully protected against UV Lens is not one feature it is the combination of the features to insure patient comfort Potential benefits to ECPs Lens materials positioning 1.74 High-Index Trivex® tribrid™ HIGH END Europe & US 1.67 High-Index 1.60 High-Index Europe Europe & US MID-RANGE Polycarbonate US BASE / ENTRY 1.56 Mid-Index ADC / CR-39® Global Asia DIOPTRES 0.00 +/-3.0 +/-7.00 Knowledge is power • Understanding the patient – Understanding patients needs – Understanding patients lifestyle – Understanding patients expectations • Educating patients about lenses • Repeating the benefits of recommended lens • Using regular mailings to keep in touch with the patient. Lens materials - market share UK HIGH END 0,58% 20,12% MID-RANGE 3,6% 1,80% ENTRY 73% Source: Strategy with Vision, market data for Y2011 Lens design - market share UK 21,32% 11,27% 67,41% 40% 60% Source: Strategy with Vision, market data for Y2011 Lens coatings - market share UK HIGH END 18,80% 20,30% MID-END 17,40% ENTRY 43,40% Source: Strategy with Vision, market data for Y2011 Have our dispensing trends evolved with the technology? To summarize - market share UK 18,80% HIGH END 40% 0,58% 20,30% MID-END 60% 23,72% 60,80% ENTRY 11,27% 73% Source: Strategy with Vision, market data for Y2011 Consumer trends UK is becoming one of the worlds most web and gadget obsessed countries according to the latest survey results from Ofcom's annual communications market report. • Britain has become a gadget-obsessed nation, watching more television online, spending more on internet shopping and using smartphones and tablets to access the web more heavily than any of the world's leading economies, according to new research. • The British love of the latest devices has even seen the UK overtake Japan in mobile internet use, according to the report from media regulator Ofcom, which compares data across 17 countries, including the US, China, India, Russia, Brazil, Ireland, Sweden, France and Germany. • Mark Sweney • The Guardian, Thursday 13 December 2012 • Britons are biggest online shoppers in developed world • Britain is the biggest online shopping nation in the developed world, with almost two-thirds of adults using the internet to buy goods or services. • By James Hall, Consumer Affairs Editor • 2:17PM GMT 01 Feb 2012 PATIENT COMFORT Questions and Answers from live Webinar ABDO College, 30th April 2014 Q: With regards to Tinting Trivex lenses I understand there can be concerns with A/R consistency, pinholes and bubbling. Has this now been resolved in 2014? Does tinting affect impact resistance? A: Trivex lenses tint best when combined with a tintable hard coating as the tint is more readily absorbed into the coating. Trivex material itself can be difficult to tint but again if combined with the proper tintable hard coating it may be able to be tinted. As far as compatibility with AR coating – Trivex is compatible with all AR coatings and no manufacturers have reported any issues or problems. Any “bubbling” or “pinhole” defect is most likely related to the tinting process and the lens not being tinted properly. When tinting Trivex and then applying an AR coating – labs generally have to over tint the lens as some of the color is removed during the AR process so in order to match the requested color labs often times have to add more color than needed and gauge the amount the will be released during the additional processing and sometimes because of this the lens may be tinted more than once and this could affect the tintable hard coating so any defects seen would be a result of the tinting process and note specifically related to the Trivex material. Tinting does not affect impact resistance. Q: I was surprised to hear that the UV blocker wears off. How would I explain to my patient that it wears off and cannot be replaced if lenses are still in good condition and prescription has not changed, and it cannot be replaced. Therefore not protecting the eye from UV. A: Whether or not the UV protection can be replaced is dependent on what other coatings are on the lens – if it is a lens with no other coatings than it may be able to be re-applied. I would mainly be concerned with CR-39 or plastic lenses with no other coatings except the UV absorber – In other lenses and coatings the UV protection is part of the lens and should not wear down. With CR-39 or plastic lenses in which a UV dye was used – this is the case where as it may wear off over time or reduce its efficiency.
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