Cemental tear is a rare but probably underdiagnosed condition that may be a factor in rapid periodontal breakdown. The present case report describes the regenerative treatment of a periodontal lesion around a mandibular canine in a 50-year-old woman. The preoperative radiograph revealed a small cemental tear within an intrabony lesion. The three-wall bony lesion was treated with a barrier membrane and followed for 3 years. Periodontal pocket reduction was 5.5 mm, and attachment gain amounted to 3.5 to 4.5 mm. Standardized radiographs showed remarkable, 1.6-mm bone fill of the intrabony lesion. Also, a band of keratinized tissue had formed.