Specific to Envista, we posted 9.5% core growth in Q1, and for the 4th straight quarter now, all of our major businesses delivered positive growth. As we did across 2025, we reinvested a meaningful portion of our gains into continued future growth as sales and marketing and R&D investment were both up double digits. We also completed an accretive tuck-in acquisition in our Implants platform, of which I'll say more in just a moment. Our improved execution and operating discipline continued in Q1, helping to convert good top-line growth into even better adjusted EBITDA and EPS growth, up 25% and 50% respectively.
Our continued momentum and strong start to the year give us confidence in reaffirming the 2026 guidance that we issued on our Q4 2025 call. Let's now turn to progress we made in the quarter in support of our three core priorities of growth, operations, and people. In terms of segment performance, Specialty Products & Technologies grew core revenue by more than 8%, while Equipment & Consumables was up nearly 12%. Developing markets grew high single digits, with some specific exceptions like China due to VBP and the Middle East due to the conflict.
Rounding out growth, volume contributed over seven points in Q1, with price accounting for the remaining 2+%. Improving manufacturing productivity helped drive 100 basis points of gross margin expansion, and when combined with sustained G&A productivity, adjusted EBITDA margin expanded by 120 basis points. With that loan now resolved, our Q1 effective tax rate declined, contributing to the 50% year-on-year EPS growth that I mentioned earlier. In addition to this, we launched an enterprise-wide talent development program last quarter with structured opportunities for career advancement and personal growth.