As a periodontist who knows about the numerous barriers we face when talking about possibilities of smoking cessation as part of periodontal treatment I have always expressed empathy even when mentioning serious consequences of Smoking, certainly not discrimination. Currently, dentists are not really educated for that task. It is hoped that this might change in future curricula but I’m not sure.
In a previous post, I had questioned how reliable Global Burden of Disease (GBD) estimates of severe periodontitis actually are. The reason was a recent editorial by Kocher and Holtreter (2017) who had asked, “Is the prevalence of periodontitis declining or not?” In a paper by Kassebaum et al. (2014), severe periodontitis had been identified as the 6th most prevalent disease worldwide with 11.2% (743 million) cases in 2010; while in a later paper by the same authors (Kassebaum et al. 2017) an estimate of 7.4% (538 million) in 2015 was published. Case definitions had not changed but maybe the data base has grown?
Prevalence (even incidence) data by Kassebaum et al. (2014, 2017) have been widely discussed, and a questionable measure, disability-adjusted life years (DALY), criticized, as it adopts disability weights which are, in case of severe periodontitis, very low as compared to serious diseases and conditions.
I had contacted Dr. Kassebaum at the University of Washington in Seattle and received meanwhile a kind response. He provided me with a link to the GBD database. Below is displayed the age-standardized prevalence of severe periodontitis in 2016.
Denmark and Kenya lead with more than 20% age-standardized prevalence.
In my previous post, I have emphasized that relative risks for certain steps of a complex dental procedure should be multiplied, not added, to get an idea of the overall relative risk for a, say, catastrophic outcome like tooth loss. There is probably no evidence, however, for the figures of my hypothetical example taken from restorative dentistry research.
In contrast, plenty of evidence for various risk factors for tooth loss in periodontally diseased patients during maintenance therapy has been published in recent cohort studies. The information provided (called internal evidence) may in fact be used for validation in unrelated patient populations (external evidence).
Let’s consider a popular example. In the study by Fardal et al. (2004), in a private specialist practice, 100 consecutive patients with periodontitis had been recalled, after proper treatment, for maintenance visits for 9 to 11 years. A few teeth, i.e. 36 out of 2436 teeth present at baseline, were subsequently lost during supportive periodontal therapy (1.5% of all teeth), all due to recurrent periodontal disease. The authors conducted a logistic regression analysis with the patient as statistical unit and identified male gender, older than 60 years of age, and smoking as significant covariates with an unfavorable effect on tooth loss. Participating in the offered maintenance program was not significantly associated with tooth loss, as were other covariates. These results were reported in Table 5 of the paper (here slightly edited).
As dental patients commonly present with numerous problems, predicting tooth loss when encountering a patient with destructive periodontal disease is important when making a comprehensive treatment plan. It does not come as a surprise that prediction models are becoming popular as evidence mounts.
There are also quite complicated procedures in restorative dentistry, and sometimes there is no evidence for a certain question raised, for example, by the patient herself.
The above picture was taken during explorative surgery as the radiograph was inconclusive as to the reason for the deep pocket at the buccal surface of tooth #14. There were no pockets at the mesial, distal, or palatal surfaces, and apart for some pockets of 4 mm, the patient did not suffer from periodontitis.