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1-Year chronic periodontitis non-surgical treatment: comparison of upper and lower sites clinical attachment loss recovery

Introduction: Periodontitis presents complex bacterial biofilms and multifactorial mechanisms, being its management a major challenge [1–3]. Our recent observational study exposed smoking and aging as risk indicators for clinical attachment loss (CAL), but it would be significant to study how CAL levels variate after periodontal treatment. The aim of this study was to assess CAL variation at 3, 6 and 12 months’ follow-up in patients that underwent non-surgical periodontal treatment. Materials and methods: 24 patients, from the Periodontology Department of the Egas Moniz Dental Clinic, were retrospectively analyzed during the period of 2013-2017. The patients had moderate to severe periodontitis according to Page and Eke’s case definitions [4], and were treated by dentists at various levels in their specialist training. All patients received non-surgical periodontal treatments and follow-up visits at 3, 6 and 12 months. Six sites per tooth were measured (mesiobuccal, buccal, distobuccal, mesiolingual, lingual, distolingual) and recorded, excluding third molars. CAL was measured with a CP-12 SE (Hu-Friedy, Chicago, IL, USA). This study was approved by the Egas Moniz Ethics Committee (IRB approval number: 595). Results: The upper and lower teeth initial mean PD were 5.91 (±2.18) and 5.7 (±1.93), respectively, and they were not statistically different (p = 0.2501, independent t-test). Overall, upper teeth had significantly less recovery that lower teeth. Figure 1 presents CAL recovery levels at 3, 6 and 12 months’ follow-up of non-surgical periodontal treatment.Figure 1. CAL levels variation at 3, 6 and 12 months' follow-up of non-surgical periodontal treatment. *P < 0.05, **P < 0.01, ***P < 0.001. SD: Standard Deviation; 3M: 3 months; 6M: 6 months; 12M: 12 months. Discussion and conclusions: Overall, lower teeth presented increased CAL healing than upper teeth. Besides, lower teeth appear to present firm prospective healing levels after non-surgical periodontal therapy and, oppositely, upper teeth apparently present a slight recurrence. Future research is necessary to unveil the reasons for this difference.