Periodontal healing in horizontal and vertical defects following surgical or non-surgical therapy

The aim of the present study was to investigate any relationship between the level of oral hygiene and probing pocket depth reduction over time after periodontal treatment in sites with either vertical or horizontal destructions. The investigation was conducted as a retrospective study on a 3-year consecutive referral population of periodontitis-prone patients based on full-mouth oral radiographic examinations, probing pocket depth registrations and plaque scores. The analyses were performed on a final sample of 3064 sites in 107 patients with regression analysis after adjusting for dependence within the patient. Probing pocket depth was significantly less reduced over time in sites with vertical destructions compared to sites with horizontal destructions following non-surgical treatment. Furthermore, the difference in probing pocket depth reduction between vertical and horizontal defects following non-surgical treatment increased over time in sites with plaque compared to sites without plaque, thus reflecting the importance of the patient's plaque control, especially in sites with vertical destructions. However, the difference in probing pocket depth reduction between vertical and horizontal defects did not increase over time for surgically treated teeth, a finding which probably can be attributed to a more thorough debridement of vertical defects during surgery and/or osteoplasty/osteoectomy limiting the surface area upon which a long junctional epithelium can form, which may facilitate recurrence of a periodontal pocket.