中文摘要：

本病例为上颌侧切牙畸形舌侧沟致牙周牙髓联合病损病例，唇腭根面的凹陷、腭侧窄而深牙周袋、根管系统的峡部、破坏严重的唇腭骨板和迁延不愈的瘘道等，给控制根管内外感染保留该牙提出了严重挑战。本病例采用显微根管治疗技术、意向性牙再植术以及纳米生物活性材料，实现了对该患牙的感染控制、患牙保留以及牙周新附着的形成。

英文摘要：

Palatal radicular groove leads to severe endo-periodontal lesion in lateral incisors. The groove occurs on the labial and lingual root surfaces, while the localized periodontal pocket develops along the lingual groove length. The complicated root canal system, extensively destroyed bone lamella, and persistent fistula pose a challenge for root canal therapy, tooth retention, and thorough infection control inside and outside of the root canal. Combining microscopic root canal therapy with intentional replantation and nano-biomaterial application facilitates infection control, tooth retention, and formation of newly periodontal attachment.