## 3 Results
### Description of Characteristics  
The methodological characteristics of the selected studies are presented in Table 1. The study characteristics relevant to the specific research question are described as follows:  
Population: Five of the studies included were performed in Turkey [27; 28; 29; 30; 31], one in Brazil [32], and one in the United States of America with mostly Caucasian followed by black subjects [33]. The study by [PERSON] et al. 2008 investigated patients with aggressive periodontitis [32]. All remaining studies included patients with chronic periodontitis [27; 28; 29; 30; 31; 33]. All participants included in the study were systemically healthy, did not have hypersensitivity to NSAIDsIDs, and were not pregnant or lactating. Four studies [27; 28; 30; 32] excluded smokers from the study, whereas three studies [29; 31; 33] included smokers. [PERSON] et al. not only included smokers but also divided smokers and non-smokers between the test and control group [29].  
Overall, a total of 276 subjects were assessed in the meta-analysis. In detail, 135 subjects were assigned in the control group and received a placebo during scaling and root planing and 141 participants in the test group received an NSAID.  
Intervention/Comparison: All studies except for [PERSON] et al. gave oral hygiene instruction before or after the treatment. All participants in the studies received scaling and root planing with either an NSAID (test group) or a placebo (control group) [27; 28; 29; 30; 31; 32; 33]. The dose and duration of NSAID application varied between the studies depending on the length of the follow-up period. Patients were instructed to take either one or two tablets a day for 7 [32] or 10 [28; 29; 30; 31] days. [PERSON] et al. prescribed a six-week NSAID intake of one tablet a day and [PERSON] et al. a six-month NSAID intake of one tablet a day. Study periods ranged from 4 weeks to 12 months and were categorized according to an early follow-up (7 days to 4 weeks) or a late follow-up (6 to 12 weeks) (Table 2).  
Figure 1: Prisma flow chart of the study selection process for this systematic review.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Study Study** & **Periodation Characteristics (\#Gability, Age, Inclusion Criteria)** & **Non- of Patients input** & **Study Design** & **Information (\#F Data, Context)** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** & **Dance** \\ \hline
**Hollow** & **Hollowollow** & **Hollowollow** & **Hollowollow** & **Hollowollow** & **Hollowollow** & **Hollowly** & **Hollowly** & **Hollowly** & **Hollowly** \\
**Hollow** & **Hollowollow** & **Hollowollow** & **Hollowollowollow** & **Hollowollowollow** & **Hollowollowollow** & **Hollowollowollowollow** & **Hollowollowollowollow** & **Hollowollowollowollow** \\
**Hollow** & **Hollowollowollow** & **Hollowollowollow** & **Hollowollowollowollow** & **Hollowollowollowollow** & **Hollowollowollowollowollow** & **Hollowollowollowollowollow** & **H  
Outcome: All studies recorded PD, PI, and some method of gingiva inflammation recording (BOP, PBI, GBI) at baseline, different follow-up intervals, and at the final examination. [PERSON] et al. took measurements at the beginning and 10 days after the intervention as a final recording of the study, so that it represented the shortest follow-up time [29]. [PERSON] et al. distinguished PD recordings between moderate and deep pockets. Six out of seven studies documented CAL [28; 29; 30; 31; 32; 33]. Some studies examined gingival crevicular fluid (GCF) [27; 29] and prostaglandin E\({}_{2}\) (PGE\({}_{2}\)) [28; 32]. [PERSON] et al. studied interleukin-1-beta (IL-1b) levels whereas [PERSON] et al. investigated levels of MMP-8 and TNF-\(\alpha\) in subjects with chronic periodontitis.  
Study design: All studies included a control group, which used a placebo. Five controlled clinical trials were double blinded [28; 30; 31; 32; 33].