Because both Senofilcon A (147 Fatt units) and Comfilcon A (160 Fatt units) clear the 125 Dk/t Harvitt-Bonanno stromal oxygen benchmark, neither causes open-eye hypoxia. Clinical selection hinges instead on sagittal bowl depth (BC 8.4/8.8 mm vs single 8.6 mm), UV exposure, and heavy protein/lipid depositors who benefit from discarding lenses at day 14 rather than day 30.
| Clinical Parameter | Acuvue Oasys (2-Week) | CooperVision Biofinity (Monthly) | Clinical Advantage |
|---|---|---|---|
| FDA Polymer & Generation | Senofilcon A (2nd-Gen SiHy) | Comfilcon A (3rd-Gen SiHy) | Biofinity (coatless macromer) |
| Oxygen Flux (Dk/t @ -3.00D) | 147 Fatt units | 160 Fatt units | Both clear >=125 HB benchmark |
| Water Content & Modulus | 38% water · 0.72 MPa modulus | 48% water · 0.75 MPa modulus | Virtually tied soft drape |
| Base Curve (BC) & Sagitta | 8.4 mm (3.76mm) & 8.8 mm (3.47mm) | 8.6 mm single fit (3.60mm) | Oasys fits steeper/flatter eyes |
| Wetting & UV Protection | Hydraclear Plus PVP · Class 1 UV | Aquaform H-bond · No UV blocker | Oasys (99% UVB / 96% UVA block) |
| Annual Supply & Est. TCO | 26 pairs (~$260 + $195 care = $455) | 12 pairs (~$200 + $195 care = $395) | Biofinity saves ~$60/yr |
Early silicone hydrogels suffered from stiff mechanical modulus and hydrophobic surface patches because raw siloxane repels water. Acuvue Oasys (Senofilcon A) solves this as a second-generation silicone hydrogel by cross-linking high-molecular-weight polyvinylpyrrolidone (PVP)—marketed as Hydraclear Plus—directly throughout the 38%-water bulk matrix to mimic mucin-layer lubricity.
CooperVision Biofinity (Comfilcon A) advances to third-generation Aquaform chemistry: long-chain siloxane macromers lock water molecules directly via natural hydrogen bonding without relying on internal wetting additives or plasma coatings. That molecular architecture achieves an unusual pairing of high 48% water content and 160 Dk/t oxygen transmissibility while keeping tensile modulus at a supple 0.75 MPa alongside Oasys at 0.72 MPa.
Sharing an identical 14.0 mm chord diameter (DIA) does not make Oasys and Biofinity interchangeable on the eye. Applying the sagittal vault equation s = r - sqrt(r^2 - (d/2)^2) at d = 14.0 mm shows that Acuvue Oasys 8.4 mm produces a 3.76 mm bowl depth, Biofinity 8.6 mm yields 3.60 mm, and Acuvue Oasys 8.8 mm drops to a shallow 3.47 mm vault.
Patients with steeper central keratometry readings often require the snugger 3.76 mm sagitta of Oasys 8.4 mm to prevent excessive blink decentration or lower-lid edge awareness. Conversely, wearers with flatter corneas who experience tight conjunctival blanching in 8.4 mm or 8.6 mm lenses rely on the flatter 8.8 mm Oasys curve.
Replacement cadence drives both ocular comfort and annual cost. Acuvue Oasys is FDA-cleared strictly for 14-day daily wear replacement, requiring 26 pairs (two 12-packs or four 6-packs plus two pairs) per eye annually at roughly $260/yr for lenses. Biofinity runs on a 30-day monthly clock requiring 12 pairs (two 6-packs per eye) at roughly $200/yr.
Because both modalities consume the exact same nightly multi-purpose solution ($180/yr) and four quarterly CDC storage cases ($15/yr), full annual TCO lands near $455/yr for Acuvue Oasys versus $395/yr for Biofinity before optional rewetting drops. Heavy tear-lipid secretors and allergy sufferers often find a fresh blister every 14 days well worth the extra $5 per month.
Under the FTC Contact Lens Rule (16 CFR Part 315), a valid contact lens prescription specifies the exact manufacturer polymer, brand name, base curve, and diameter—meaning an optical retailer cannot legally fill a Biofinity order using an Acuvue Oasys prescription or vice versa.
During a quick diagnostic refit, your optometrist places trial blisters on both eyes, lets tear equilibrium settle for ten to fifteen minutes, evaluates fluorescein edge alignment and push-up recovery under cobalt slit-lamp magnification, and confirms over-refraction acuity before finalizing a full year supply.
Direct manufacturer-verified OTC disinfecting solutions, 90-day replacement cases, and preservative-free dry-eye support.
Formulated with HydraGlyde Moisture Matrix that embeds into silicone hydrogel surfaces like Senofilcon A and Comfilcon A to block lipid buildup.
Matches healthy tear pH (7.5) with sulfobetaine surfactant conditioning for comfortable 14-day Oasys and 30-day Biofinity wear cycles.
Contact-safe carboxymethylcellulose and hyaluronate drop to refresh silicone hydrogel pre-lens tear films during late-afternoon work.
Load the Acuvue Oasys and Biofinity brand presets inside our interactive Prescription Decoder to inspect sagittal vault and oxygen benchmarks.
No. Senofilcon A is engineered and FDA-cleared for a 14-calendar-day replacement ceiling (or 6 nights if explicitly prescribed for extended wear). Pushing Oasys to 30 days accelerates oxidized tear-lipid cross-linking across the silicone matrix, reducing wettability and elevating corneal infiltrative events.
Both rank at the top of optometric toric prescribing, using distinct stabilization physics: Acuvue Oasys employs Blink Stabilized four-zone eyelid interaction (ideal for head-tilting sports or lying sideways), while Biofinity Toric uses Optimized Toric Lens Geometry horizontal iso-thickness ballast across a massive extended XR power range.
Unlike legacy HEMA hydrogels where higher water percentage caused faster evaporative dehydration, Comfilcon A binds water directly to hydrophilic siloxane chains via hydrogen bonds. Clinical trials show comparable end-of-day tear film stability between Biofinity and PVP-infused Acuvue Oasys.
Although both carry conditional FDA extended-wear clearances (up to 6 nights for Oasys and up to 6 nights/7 days for Biofinity), optometrists strongly advise nightly removal. Closed-lid overnight wear still raises ulcerative microbial keratitis incidence 6-fold to 8-fold regardless of high Dk/t scores.
Clinical Notice: Educational resource only. Not a substitute for examination by a licensed Optometrist or Ophthalmologist.
