Table 5 Definition of periodontitis, periodontal assessment and definition of smoking

Al – Zahrani et al. 2012 [8]

≥ 20 teeth,

CAL ≥ 3 mm at ≥ 30 of the sites

(generalized moderate/severe chronic periodontits)

Full-mouth periodontal examination on all teeth excluding 3rd molars and partially erupted teeth

Smokers excluded

Bouaziz et al. 2015 [28]

≥ 12 teeth,

≥ 30 % of sites with CAL ≥ 3 mm

(moderate-to-severe generalized chronic periodontitis)

Full-mouth clinical measurements included the following:

1) PI,

2) BOP,

3) PD (mm),

4) CAL (mm),

PI, BOP, PD, and CAL measurements were performed using a manual periodontal probe at 6 sites per tooth,

PD was defined as the distance from the free gingival margin to the bottom of the pocket/sulcus, and CAL was defined as the distance from the cemento-enamel junction to the bottom of the pocket/sulcus

Non-smoker or former smoker since ≥ 5 years

Duzagac et al. 2015 [29]

≥ 20 teeth,

PD ≥ 4 mm in ≥ 30 % of periodontal sites,

BOP in ≥ 50 % of periodontal sites,

interproximal CAL > 2 mm in ≥ 20 % of periodontal sites,

radiographic evidence of bone loss, as described

by Armitage [177]

A Williams-type periodontal probe (UNC15, Hu-Friedy, Chicago, IL, USA) was used for the measurements of periodontal parameters, including PI (Silness–Löe) [178], GI (Löe–Silness) [179], BOP, PD and CAL,

all clinical periodontal measurements were performed at 6 sites per tooth (mesiobuccal, mid-buccal, distobuccal, mesiolingual, mid-lingual and distolingual),

excluding third molars

Smokers excluded

Eldin et al. 2013 [30]

n.r.

(chronic periodontitis)

Full-mouth,

4 sites per tooth (mesio-buccal, mid-buccal, disto-buccal, mid-lingual) around each tooth

n.r.

Gonçalves et al. 2015 [31]

≥ 15 teeth excluding 3rd molars and teeth with advanced decay indicated for exodontia,

>30 % of the sites with concomitant PD and

CAL ≥4 mm and a minimum of 6 teeth distributed in the different quadrants presenting at least one site with PD and CAL ≥ 5 mm and BOP at baseline

(generalized chronic periodontitis)

6 sites per tooth on all teeth excluding 3rd molars (distance between the gingival margin and the bottom of the sulcus/pocket [mm])

Smokers excluded

Gonçalves et al. 2015 [32]

≥ 15 teeth excluding 3rd molars and teeth with advanced decay indicated for exodontia,

>30 % of the sites with concomitant PD and

CAL ≥ 4 mm and a minimum of 6 teeth distributed in the different quadrants presenting at least one site with PD and CAL ≥ 5 mm and BOP at baseline

(generalized chronic periodontitis)

6 sites per tooth (mesio-buccal, mid-buccal, disto-buccal, mesio-lingual, mid-lingual, disto-lingual) excluding third molars, with a manual periodontal probe (UNC15, Hu-Friedy, Chicago, IL, USA)

Current smokers excluded, smoking within the past 10 years excluded

Lakkis et al. 2011 [33]

≥ 20 teeth,

mean CAL ≥ 2 mm

(chronic periodontitis)

6 sites per tooth

n.r.

Suvan et al. 2014 [34]

PD > 5 mm and marginal alveolar bone loss > 30 % with > 50 % of the teeth affected

(generalized severe periodontitis)

6 sites per tooth on all teeth present

Normal-group = 47 % smokers

Overweight-group = 25 % smokers

Obese-group = 15 % smokers

p - value = 0.045 (sig. on p ≤ 0.05)