The barrier to bacterial ingress around implants is primarily provided by:

• A. Bone tissue
• B. Saliva
• C. Connective tissue
• D. Gingival epithelium

Answer: (C)

The soft-tissue seal around an implant relies mainly on the connective tissue that attaches to the implant surface. This dense, collagen-rich connective tissue forms a robust barrier around the implant, creating a stable biological width and a continuous seal that limits bacteria from reaching deeper tissues. The epithelium does contribute to the surface barrier, but around implants it is not as formidable as the connective tissue attachment, which is why connective tissue provides the primary defense. Bone lies deeper and isn’t the first line of defense at the implant interface, and saliva helps with cleansing but isn’t the direct barrier to ingress.