Periodontal progression based on radiographic records: An observational study in chronic and aggressive periodontitis

The current classification assumes that aggressive periodontitis (AgP) has a faster rate of progression than chronic periodontitis (CP). However, this has not been clearly proven and difficulties exist in establishing progression. This study aimed to assess the feasibility of retrospectively utilising previous records for clinical diagnosis of periodontal diseases and to assess if two different patterns of disease progression exist between AgP and CP.

Previous radiographic records of a cohort of 235 patients clinically diagnosed with AgP or CP were requested from the referring general dental practitioners (GDPs). Comparable radiographic records were analysed in order to assess progression patterns and associate these with clinical diagnosis, by multilevel analysis.

43 patients out of the initial 235 had comparable radiographs retrieved from the GDPs. 858 sites were followed for an average 6.6 years. Radiographically, AgP showed a faster linear pattern of progression than CP (0.31mm/year vs. 0.20mm/year, p<0.001).

This study provides evidence for a faster disease progression in untreated AgP compared to CP as assessed by radiographic bone levels. Furthermore, it shows that retrievability of previous radiographs from GDPs is unpredictable and GDPs should be encouraged to send them along with their referral.

The importance of differentially diagnosing AgP and CP might be useful in establishing a clinically relevant definition for periodontal disease progression and may have an impact on the clinical management of aggressive periodontitis, since our findings show that there is continuous destruction in patients with aggressive periodontitis if left untreated.