. 2021 Jan 22;12(5):1249–1278. doi: 10.1007/s13300-021-01000-6

Table 1.

Characteristics of included randomized controlled trials

First author/year/study reference	Basic characteristics of study	Baseline T2DM/PD information (mean ± SD)	Inclusion/exclusion criteria	Treatment on PD and T2DM treatment change
Bukleta 2018 [15]	Kosovo Mean age ± SD (years): 59.49 ± 10.82 Gender (male/female): 50/50 Follow-up: 3 months Jadad score: 2	HbA1c level (%): Int: 9.59 ± 2.5; Ctr: 8.82 ± 3.01 T2DM history (year): NA Mean PPD (mm): Int: 6.52 ± 0.82; Ctr: 6.60 ± 1.47	Inclusion: diagnosed with T2DM; had a baseline HbA1c ≥ 6.5%, had at least 10 teeth (excluding third molars); had a clinical diagnosis of periodontal disease with at least one site with a PPD ≥ 5 mm, two teeth with CAL ≥ 6 mm; no modification in the pharmacological treatment of T2DM during the study period. All the patients had at least one tooth needing extraction	Int: full-mouth SRP using an ultrasonic device and periodontal curettes for the mechanical debridement. Extraction of hopeless teeth. Using mouthwash for 3 weeks (n = 50) Ctr: Extraction of hopeless teeth. Using mouthwash for 3 weeks (n = 50) T2DM treatment change: patients with modification in the pharmacological treatment of T2DM during the study period were excluded
Chen 2012 [16]	China Mean age ± SD (years): Int: 59.86 ± 9.48; Ctr: 63.2 ± 8.51 Gender (male/female): Int: 23/19; Ctr: 17/24 Follow-up: 3 months; 6 months Jadad score: 6	HbA1c level (%): Int: 7.31 ± 1.23; Ctr: 7.25 ± 1.49 T2DM history (year): Int: 8.69 ± 5.25; Ctr: 9.56 ± 6.02 Mean PPD (mm): Int: 2.66 ± 0.68; Ctr: 2.47 ± 0.57	Inclusion: diagnosed with T2DM for > 1 year, with no change in their diabetic treatment plan in the previous 2 months and with no major diabetic complication. Diagnosed with chronic PD (with a ≥ 1 mm mean CAL with 16 teeth) Exclusion: (1) the presence of a systemic disease other than diabetes that could influence the course of the periodontal disease; (2) systemic antibiotic administration within the previous 3 months; (3) pregnancy or lactation; (4) refusal to provide written informed consent; (5) had an active infection other than PD; or (6) had received periodontal treatment in the previous 12 months	Int: SRP at baseline and additional subgingival debridement at the 3-month follow-up. SRP was completed within 24 h, using standard rigid periodontal curets and ultrasonic instrumentation (n = 42) Ctr: no treatment measure or formal OHI until the end of the study (n = 41) T2DM treatment change: participants were instructed to continue with their medication and lifestyle
D'Aiuto 2018 [11]	UK Mean age ± SD (years): Int: 58.2 ± 9.7; Ctr: 55.5 ± 10.0 Gender (male/female): Int: 82/51; Ctr: 83/48 Follow-up: 6 months; 12 months Jadad score: 6	HbA1c level (%): Int: 8.1 ± 1.7; Ctr: 8.1 ± 1.7 T2DM history (year): Int: 8.3 ± 7.4; Ctr: 8.7 ± 8.4 Mean PPD (mm): Int: 3.9 ± 0.7; Ctr: 3.9 ± 0.8	Inclusion: diagnosed with T2DM for > 6 months; with moderatetosevere PD (≥ 20 periodontal pockets with PPD of > 4 mm and marginal alveolar bone loss of > 30%), and at least 15 teeth Exclusion: with uncontrolled sy0stemic diseases other than diabetes (cardiovascular diseases [including hypertension], liver diseases, pulmonary diseases, end stage renal failure, or neoplasm); hepatitis B or HIV infection; chronic treatment (> 2 weeks) with drugs known to affect periodontal tissues (phenytoin or ciclosporin); chronic systemic antibiotic treatment; pregnancy or lactation	Int: OHI. Extraction of hopeless teeth. Initial single session of whole mouth SRP. After initial SRP, received root scaling every 3 months. Twp months after first SRP, received additional root scaling or periodontal surgery (n = 133) Ctr: OHI. Extraction of hopeless teeth. Initial single session of whole mouth SGS. After initial SGS, received SGS every 3 months. If SRP were needed, withdrew (n = 131) T2DM treatment change: mo significant lifestyles or diets changes during study. Medication change was similar between groups during the trail
Engebretson 2013 [9]	USA Mean age ± SD (years): Int: 56.7 ± 10.5; Ctr: 57.9 ± 9.6 Gender (male/female): Int: 143/114; Ctr: 134/123 Follow-up: 3 months; 6 months Jadad score: 6	HbA1c level (%): Int: 7.84 ± 0.65; Ctr: 7.78 ± 0.60 T2DM history (year): Int: 12.3 ± 8.2; Ctr: 11.3 ± 8.4 Mean PPD (mm): Int: 3.28; Ctr: 3.26	Inclusion: age > 35 years.; diagnosed with T2DM of > 3 months HbA1c between 7.0 to 9.0%; no changes in diabetes medications within the last 3 months; not pregnant; diagnosed with moderate to advanced PD (CAL and PPD > 5 mm in ≥ 2 quadrants); at least 16 natural teeth; n periodontal treatment in the prior 6 months Exclusion criteria: limited life expectancy; diabetes related emergency within 30 days; use of nonsteroidal anti-inflammatory drugs other than daily low-dose aspirin; use of immune-suppressive medications; antibiotic use (> 7 days within 30 days of enrollment); dialysis; risk of bleeding complications; or heavy alcohol consumption	Int: SRP for > 160 min using curettes and ultrasonic instruments during ≥ 2 sessions completed within 42 days of the baseline visit. OHI after treatment. Used mouthwash twice daily for 2 weeks. Three and 6 months after the baseline visit, SRP and OHI were given during a single session (n = 257) Ctr: OHI at the baseline and 3- and 6-month visits. Following their 6-month visit, SRP were given (n = 257) T2DM treatment change: participants agreed to not change diabetes medications during the trial unless medically indicated. Medication change was similar between groups during the trail
Fu 2014 [17]	China Mean age (years): 58.6 (range 40–67) Gender (male/female): 67/53 Follow-up: 6 months Jadad score: 1	HbA1c level (%): Int: 9.46 ± 1.21; Ctr: 9.53 ± 1.14 T2DM history (year): NA Mean PPD (mm): Int: 5.73 ± 0.39; Ctr: 5.77 ± 0.44	Inclusion: diagnosed with T2DM and PD Exclusion: with uncontrolled systemic diseases other than diabetes	Int: SRP. Used mouthwash and oral antibiotics pre- and post-SRP. Details of SRP were NA (n = 60) Ctr: None (n = 60) T2DM treatment change: both groups received standard T2DM treatment, including diet, exercise, and insulin (details NA)
Fu 2014 [18]	China Mean age ± SD (years): Int: 51.6 ± 3.8; Ctr: 50.3 ± 3.9 Gender (male/female): Int: 17/14; Ctr: 15/16 Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 9.88 ± 0.86; Ctr: 9.91 ± 0.78 T2DM history (year): Int: 3.35 ± 1.43; Ctr: 3.21 ± 1.32 Mean PPD (mm): Int: 5.76 ± 0.51; Ctr: 5.68 ± 0.47	Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 3 months; with PD (≥ 6 sites with PPD of > 4 mm and CAL of > 4 mm), and at least 15 teeth Exclusion: with uncontrolled systemic diseases other than diabetes; with sever diabetes complications; chronic systemic antibiotic treatment	Int: SRP. Used oral antibiotics pre- and post-SRP (roxithromycin, 0.2 g qid; metronidazole, 0.4 g tid). Details of SRP were NA (n = 31) Ctr: None (n = 31) T2DM treatment change: both groups received standard T2DM treatment, including oral repaglinide (1 mg tid) and metformin (0.5 g tid)
Gu 2011 [19]	China Age (year): 60–70 Gender (male/female): 38/22 Follow-up: 6 months Jadad score: 4	HbA1c level (%): Int: 9.46 ± 1.21; Ctr: 9.53 ± 1.14 T2DM history (year): NA Mean PPD (mm): Int: 5.94 ± 1.02; Ctr: 6.08 ± 0.92	Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication recently; baseline HbA1c level between 8 and 12%; without systemic diseases other than diabetes; with PD (≥ 6 sites with PPD of > 5 mm); radiograph showed multiple teeth showed alveolar bone loss of > 1/3 of root; at least 15 teeth; did not use antibiotics in the last 3 months; did not receive periodontal therapy in last 6 months	Int: OHI. Extraction of hopeless teeth. SRP. Used mouthwash for 2 weeks post SRP. Details of SRP were NA (n = 30) Ctr: None (n = 30) T2DM treatment change: participants did not change diabetes medications during the trial
Hao 2016 [20]	China Mean age ± SD (years): Int: 61.06 ± 10.26; Ctr: 63.59 ± 8.97 Gender (male/female): Int: 18/11; Ctr: 16/14 Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 9.07 ± 1.54; Ctr: 9.21 ± 1.59 T2DM history (year): Int: 7.65 ± 5.33; Ctr: 6.85 ± 4.67 Mean PPD (mm): Int: 4.12 ± 0.70; Ctr: 4.05 ± 0.63	Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 2 months; with PD (≥ 2 teeth with PPD of > 5 mm and CAL of > 2 mm), and at least 16 teeth Exclusion: with uncontrolled systemic diseases other than diabetes; with severe diabetes complications; antibiotic use (> 7 days within 30 days of enrollment); received periodontal therapy in last 6 months; pregnancy or lactation	Int: OHI and SRP. Details of SRP were NA (n = 30) Ctr: None (n = 30) T2DM treatment change: both groups received standard T2DM treatment, including diet, exercise, and medications (details NA)
Katagiri 2009 [21]	Japan Mean age ± SD (years): Int: 60.3 ± 9.9 Ctr: 59.0 ± 4.8 Gender (male/female): Int: 21/11; Ctr: 6/11 Follow-up: 3 months; 6 months Jadad score: 2	HbA1c level (%): Int: 7.2 ± 0.9; Ctr: 6.9 ± 0.9 T2DM history (year): Int: 11.3 ± 6.4; Ctr: 8.8 ± 7.5 Mean PPD (mm): Int: 3.0 ± 0.9; Ctr: 2.8 ± 0.9	Inclusion: age between 39–75 years, HbA1c between 6.5–10.0%; without severe diabetic complications; no evidence of systemic diseases; no systemic antibiotics during the preceding 3 months; no pregnancy or lactation; no allergy to tetracycline; no smoking; and no modifications in the treatment of diabetes in last 2 months; at least 11 teeth, with PD (≥ 2 teeth with PPD of > 4 mm); no periodontal treatment in last 6 months	Int: SRP was done using ultrasonic instrumentation. The SRP was completed over the course of four visits within 2 months. 10 mg of minocycline ointment was administered topically in every periodontal pocket at the end of each visit. OHI (n = 32) Ctr: OHI (n = 17) T2DM treatment change: the doses and kinds of anti-diabetic drugs, and methods of diet and exercise were not changed
Kaur 2015 [22]	India Mean age ± SD (years): Int: 51.82 ± 5.85; Ctr: 52.94 ± 6.03 Gender (male/female): Int: 22/28; Ctr: 26/24 Follow-up: 3 months; 6 months Jadad score: 2	HbA1c level (%): (a): Int: 6.03 ± 0.47 Ctr: 5.94 ± 0.75 (b): Int: 9.99 ± 2.02 Ctr: 9.81 ± 2.24 T2DM history (year): Int: 8.57 ± 6.39; Ctr: 7.05 ± 4.43 Mean PPD (mm): (a): Int: 2.82 ± 0.44 Ctr: 2.92 ± 0.58 (b): Int: 3.08 ± 0.45 Ctr: 3.23 ± 0.48	Inclusion: diagnosed with T2DM for > 12 months; no change in T2DM medication use during the 2 months before the study or during the study; age between 45 and 60 years; presence of ≥ 12 teeth (excluding third molars); diagnosed as moderate (> 2 sites with CAL > 4 mm and > 1 site with PPD > 4 mm) or severe (> 2 sites with CAL > 6 mm and > 1 site with PPD > 5 mm) generalized chronic PD Exclusion: had systemic disease that could influence the course of periodontal disease; pregnant or lactating; current or ex-smokers; major diabetic complications; a history of systemic antibiotic use within the previous 3 months or periodontal treatment during the previous 6 months	Int: OHI. Four SRP sessions over a maximum of 2 weeks, using Gracey curettes and an ultrasonic scaler. Additional supportive SRP was done when necessary (n = 50) Ctr: None (n = 50) T2DM treatment change: no change in T2DM medication use during the 2 months before the study or during the study
Kiran 2005 [23]	Turkey Age (year): Int: 55.95 ± 11.21; Ctr: 52.82 ± 12.27 Gender (male/female): Int: 10/12; Ctr: 8/14 Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 7.31 ± 0.74; Ctr: 7.00 ± 0.72 T2DM history (year): Int: 9.32 ± 8.36; Ctr: 8.05 ± 5.90 Mean PPD (mm): Int: 2.29 ± 0.49; Ctr: 2.24 ± 0.70	Inclusion: diagnosed with T2DM with HbA1c values between 6 and 8%; creatinine values < 1.4 mg/dl; liver function tests were not up to threefold the normal range; no major diabetic complications; no history of systemic antibiotic administration within the last 3 months; no periodontal treatment 6 months prior to the study	Int: OHI and SRP. 9 patients had 9 teeth with periapical lesions. 4 teeth were extracted and 5 had root canal treatment (n = 22) Ctr: OHI. 5 patients had 5 teeth with periapical lesions where they received root canal treatment (n = 22) T2DM treatment change: no change in the medication or diet was made for both groups during the study period. None of the groups received any additional guidance in managing their diabetic status
Li 2011 [24]	China Mean age ± SD (years): Int: 58.7 ± 10.73; Ctr: 62.4 ± 9.18 Gender (male/female): Int: 51/39; Ctr: 19/26 Follow-up: 3 months; 6 months Jadad score: 1	HbA1c level (%): Int: 7.33 ± 1.37; Ctr: 7.25 ± 1.54 T2DM history (year): NA Mean PPD (mm): Int: 2.48 ± 0.56; Ctr: 2.62 ± 0.68	Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 2 months; with PD and at least 15 teeth; no periodontal treatment in last 12 months; did not use antibiotics in the last 3 months Exclusion: with systemic diseases other than diabetes; with severe diabetes complications; with acute infection; pregnancy or lactation	Int: OHI. Extraction of hopeless teeth. SRP at baseline and additional SRP at the 3-month follow-up. First SRP was done within 24 h (n = 90) Ctr: OHI (n = 45) T2DM treatment change: NA
Makaky 2019 [25]	Egypt Mean age ± SD (years): Int: 52.95 ± 6.523; Ctr: 52.23 ± 7.028 Gender (male/female): Int: 18/26; Ctr: 20/24 Follow-up: 3 months Jadad score: 4	HbA1c level (%): Int: 8.12 ± 0.74; Ctr: 8.21 ± 0.71 T2DM history (year): NA Mean PPD (mm): Int: 4.99 ± 0.75; Ctr: 5.01 ± 0.83	Inclusion: diagnosed with T2DM for > 5 years with HbA1c level from 7 to 9%; no change in diabetes treatment over the previous 3 months; diagnosis with chronic PD (> 4 teeth with one site with a CAL > 3 mm and PPD > 4 mm); 30% sites with CAL and pocket depth PD > 4 mm; at least 6 teeth; age from 40 to 70 years Exclusion: pregnancy; alcoholism and smoking; presence of any systemic disorders other than hypertension and T2DM; with T2DM major complications; antimicrobial therapies in the last 6 months; periodontal therapies in the last 6 months; allergy to metronidazole and amoxicillin	Int: OHI. SRP using ultrasonic apparatus in a single 2-h session. After SRP, using systemic antibiotics for 2 weeks (metronidazole 400 mg tid and amoxicillin 500 mg tid) (n = 44) Ctr: None (n = 44) T2DM treatment change: NA
Mauri-Obradors 2018 [26]	Spain Mean age ± SD (years): Int: 61 ± 11; Ctr: 62 ± 10 Gender (male/female): Int: 17/25; Ctr: 20/28 Follow-up: 6 months Jadad score: 4	HbA1c level (%): Int: 7.65; Ctr: 7.75 T2DM history (year): Int: 10; Ctr: 11 Mean PPD (mm): Int: 3.5; Ctr: 3.0	Inclusion: diagnosed with T2DM for > 1.5 years; with generalized chronic PD (> 9 teeth present and > 30% of the sites with a PPD and CAL > 4 mm) Exclusion: antibiotic treatment during the previous 15 days or for periods > 10 days during the last 3 months; SRP within the past 6 months; pregnancy; significant changes in diabetes medication during the course of the study; with other serious systemic disease	Int: OHI and SRP. Additional SRP when needed (n = 36) Ctr: OHI and SGS. (n = 44) T2DM treatment change: patients had significant changes in diabetes medication during the course of the study were excluded
Mizuno 2017 [27]	Japan Mean age ± SD (years): Int: 61.2 ± 9.2; Ctr: 62.8 ± 12.1 Gender (male/female): Int: 13/7; Ctr: 15/2 Follow-up: 3 months; 6 months Jadad score: 5	HbA1c level (%): Int: 7.5 ± 1.7; Ctr: 7.7 ± 1.2 T2DM history (year): NA Mean PPD (mm): Int: 2.4 ± 0.5; Ctr: 2.4 ± 0.7	Inclusion: diagnosed with T2DM for > 2 months; diagnosed with mild to advanced chronic PD (> 2 sites with CAL > 3 mm and PPD > 4 mm or 1 site with PPD > 5 mm); age > 30 years Exclusion: pregnancy; inappropriate status for the trials, such as limited life expectancy and diabetes-related emergency; received periodontal treatment in the prior 6 months	Int: at the baseline visit, receive OHI and one session SGS. Within 42 days after the baseline visit, receive SRP (2–3 sessions, each time > 60 min) using curettes and an ultrasonic instrument (n = 20) Ctr: At the baseline visit, receive OHI and one session SGS (n = 17) T2DM treatment change: of the 30 participants with medication data available, both groups had no protocol defined changes during the study
Moeintaghavi 2012 [28]	Iran Mean age ± SD (years): 50.29 ± 3 Gender (male/female): Int: 9/13; Ctr: 11/7 Follow-up: 3 months Jadad score: 6	HbA1c level (%): Int: 8.15 ± 1.18; Ctr: 8.72 ± 2.22 T2DM history (year): NA Mean PPD (mm): Int: 2.31 ± 0.65; Ctr: 2.06 ± 0.24	Inclusion: diagnosed with T2DM with HbA1c over 7%, and no major diabetic complications; using glibenclamide and metformin, without insulin administration for T2DM; no systemic antibiotic administration or periodontal treatment within the last 6 months; diagnosed with mild to moderate PD Exclusion: presence of systemic diseases other than T2DM that could influence the course of PD; intake of immunosuppressive drugs, steroids, hydantoin or non-steroidal anti-inflammatory drugs; tobacco use; pregnancy or intention to become pregnant during the study period; fixed orthodontic appliances	Int: OHI and extraction of unsalvageable teeth. Then SRP by using an ultrasonic device and standard periodontal curettes with no time limitation. No additional periodontal therapy was given (n = 22) Ctr: OHI and extraction of unsalvageable teeth (n = 18) T2DM treatment change: all patients were under strict medical supervision and, as a prerequisite, no additional guidance in managing diabetic status or changes in diet, medication or physical therapy was given
Raman 2014 [29]	Malaysia Age (year): Int: 57.7 ± 9.9; Ctr: 54.6 ± 6.2 Gender (male/female): Int: 11/4; Ctr: 9/8 Follow-up: 3 months Jadad score: 5	HbA1c level (%): Int: 7.8 ± 1.5; Ctr: 7.6 ± 1.5 T2DM history (year): NA Mean PPD (mm): Int: 2.56 ± 0.57; Ctr: 2.29 ± 0.69	Inclusion: diagnosed with T2DM; diagnosed with moderate to advanced chronic PD, with at least 12 teeth present and with 5 or more sites of PPD > 5 mm and CAL > 4 mm in at least 2 different quadrants which bled on probing Exclusion: a history of systemic antibiotic usage over the previous 4 months; having received non-surgical periodontal treatment within the past 6 months or surgical periodontal treatment within the past 12 months; pregnancy; change of medication for diabetes during the course of the study; current smoker; or history of a cerebrovascular or cardiovascular event within the past 12 months	Int: OHI. SRP in a single visit using an ultrasonic scaler and Gracey curretes. 0.12% chlorhexidine mouthrinse (tid, 14 days) after SRP (n = 15) Ctr: OHI (n = 17) T2DM treatment change: participants who changed medication for diabetes during the course of the study were excluded
Singh 2008 [30]	India Age (years): NA Gender (male/female): NA Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 7.9 ± 0.7; Ctr: 8.08 ± 0.7 T2DM history (year): NA Mean PPD (mm): Int: 2.67 ± 0.35; Ctr: 2.44 ± 0.26	Inclusion: diagnosed with T2DM; no major diabetic complications; no systemic diseases other than T2DM that could influence the course of PD; with moderate to advanced PD (> 30% of the teeth with a PPD > 4 mm) Exclusion: with uncontrolled T2DM; less than 16 teeth; had systemic antibiotic administration in last 3 months; had periodontal treatment in last 6 months	Int: Extraction of hopeless teeth and SRP (n = 15) Ctr: Extraction of hopeless teeth (n = 15) T2DM treatment change: no change of medication and diet was modified for the participants
Telgi 2013 [31]	India Mean age ± SD (years): NA Gender (male/female): NA Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 7.68 ± 0.63; Ctr: 7.56 ± 0.59 T2DM history (year): NA Mean PPD (mm): Int: 5.05 ± 0.70; Ctr: 5.11 ± 0.57	Inclusion: diagnosed with T2DM; blood sugar controlled only with oral hypoglycemic agents; mild to moderate PD (PPD of 4–5 mm); presence of a minimum of 28 teeth; and no systemic antibiotic administration and no periodontal treatment in last 6 months Exclusion: patients with systemic diseases other than T2DM; tobacco and alcohol user; and suffering from oral disease that needed emergency treatment	Int: SRP. OHI and regularly used 0.12% chlorhexidine mouthwash (qd) (n = 15) Ctr: OHI and regularly used 0.12% chlorhexidine mouthwash (qd) (n = 15) T2DM treatment change: NA
Tsobgny-Tsague 2018 [32]	Cameroon Mean age ± SD (years): Int: 51.2 ± 7.8; Ctr: 51.7 ± 9.9 Gender (male/female): Int: 8/7; Ctr: 5/10 Follow-up: 3 months Jadad score: 5	HbA1c level (%): Int: 9.7 ± 1.6; Ctr: 8.9 ± 0.9 T2DM history (year): Int: 5.0 ± 3.86; Ctr: 4.26 ± 3.3 Mean PPD (mm): Int: 3.0 ± 0.4; Ctr: 3.1 ± 0.6	Inclusion: poorly controlled T2DM, with moderate to severe chronic PD, and having at least 11 teeth in the mouth Exclusion: periodontal treatment; alteration in diabetes treatment 6 months prior to the study; onset of systemic diseases or an acute condition; use of immunosuppressive medications or other drugs; or presence of conditions able to alter PD clinical features (pregnant women, alcohol users, smokers and acute anemia)	Int: OHI. A single SRP using ultrasonic device and Gracey’s curettes. Chlorhexidine gluconate 0.2% as mouth wash (10 ml bid for 5 days) (n = 15) Ctr: OHI (n = 15) T2DM treatment change: NA
Wang, J 2013 [33]	China Mean age ± SD (years): 35–74 Gender (male/female): 32/43 Follow-up: 3 months Jadad score: 1	HbA1c level (%): Int: 7.57 ± 1.62; Ctr: 7.73 ± 1.74 T2DM history (year): 7.68 ± 1.37 Mean PPD (mm): Int: 4.21 ± 0.65; Ctr: 4.01 ± 0.73	Inclusion: diagnosed with T2DM and PD Exclusion: received periodontal treatment in last 6 months; defective prosthesis; edentulous; with severe diseases other than diabetes; mental disorders; use of antibiotics or steroids in last 6 months	Int: OHI. Initial single session of whole mouth SGS using ultrasonic instrumentation. After 1 week received SRP and took oral antibiotics (amoxicillin and metronidazole) for 3 days (n = 37) Ctr: None (n = 38) T2DM treatment change: NA
Wang 2017 [34]	China Mean age ± SD (years): Int: 61.2 ± 9.2; Ctr: 61.90 ± 6.75 Gender (male/female): Int: 12/7; Ctr: 14/6 Follow-up: 3 months Jadad score: 3	HbA1c level (%): Int: 7.63 ± 0.89; Ctr: 7.67 ± 1.32 T2DM history (year): Int: 8.47 ± 3.08; Ctr: 7.70 ± 4.69 Mean PPD (mm): Int: 3.66 ± 0.60; Ctr: 3.85 ± 0.58	Inclusion: diagnosed of T2DM for > 12 months with HbA1c from 6.5–10.0%; with chronic PD (more than 30% of teeth with PPD ≥ 5 mm and CAL > 4 mm, or > 60% of teeth with PPD > 4 mm and CAL ≥ 3 mm); at least 15 remaining teeth; body mass index < 30; without periodontal treatment in the previous 6 months; without antibiotic or NSAIDs administration in the 3 months; without serious systemic diseases or complications	Int: OHI and SRP. Also received extraction of hopeless teeth, and the restoration of balanced occlusion (n = 19) Crt: None (n = 20) T2DM treatment change: to guard against the effects of the periodontal intervention on glycemic control and adipokines, no changes in medications or diet were made for any subject during the study period
Zhang 2013 [35]	China Mean age ± SD (years): Int: 60.4 ± 9.77; Ctr: 62.7 ± 10.7 Gender (male/female): Int: 21/28; Ctr: 10/12 Follow-up: 3 months Jadad score: 4	HbA1c level (%): Int: 7.68 ± 1.22; Ctr: 7.38 ± 1.30 T2DM history (year): Int: 8.63 ± 4.20; Ctr: 7.29 ± 5.61 Mean PPD (mm): Int: 2.50 ± 0.45; Ctr: 2.43 ± 0.47	Inclusion: diagnosed to have T2DM > 1 year with HbA1c > 5.5%; diagnosed with chronic PD (at least 4 teeth with PPD > 5 mm, CAL > 4 mm, and bleeding on probing distributed in n > 2 quadrants); at least 16 teeth; age 35–80 years Exclusion: accompanied with other systemic immune diseases; administered with antibiotics, immunomodulators, contraceptives, or any other form of hormone within the past 3 months; underwent modified T2DM treatment strategy within 3 months; had periodontal treatment within the past 12 months; needed extraction or endodontic treatment; smokers; pregnant or lactating women	Int: OHI and SRP (including manual curettage). SRP were completed within 2 weeks after the baseline evaluation (n = 49) Ctr: None (n = 22) T2DM treatment change: the recruited patients were instructed to maintain their previous diet and exercise habits and to inform the authors whenever their glucose control treatment was changed. Patients were dropped from the study if their diabetes treatment scheme was changed

First author/year/study reference

Basic characteristics of study

Baseline T2DM/PD information (mean ± SD)

Inclusion/exclusion criteria

Treatment on PD and T2DM treatment change

Bukleta 2018 [15]

Kosovo

Mean age ± SD (years): 59.49 ± 10.82

Gender (male/female): 50/50

Follow-up: 3 months

Jadad score: 2

HbA1c level (%): Int: 9.59 ± 2.5; Ctr: 8.82 ± 3.01

T2DM history (year): NA

Mean PPD (mm): Int: 6.52 ± 0.82; Ctr: 6.60 ± 1.47

Inclusion: diagnosed with T2DM; had a baseline HbA1c ≥ 6.5%, had at least 10 teeth (excluding third molars); had a clinical diagnosis of periodontal disease with at least one site with a PPD ≥ 5 mm, two teeth with CAL ≥ 6 mm; no modification in the pharmacological treatment of T2DM during the study period. All the patients had at least one tooth needing extraction

Int: full-mouth SRP using an ultrasonic device and periodontal curettes for the mechanical debridement. Extraction of hopeless teeth. Using mouthwash for 3 weeks (n = 50)

Ctr: Extraction of hopeless teeth. Using mouthwash for 3 weeks (n = 50)

T2DM treatment change: patients with modification in the pharmacological treatment of T2DM during the study period were excluded

Chen 2012 [16]

China

Mean age ± SD (years): Int: 59.86 ± 9.48; Ctr: 63.2 ± 8.51

Gender (male/female): Int: 23/19; Ctr: 17/24

Follow-up: 3 months; 6 months

Jadad score: 6

HbA1c level (%): Int: 7.31 ± 1.23; Ctr: 7.25 ± 1.49

T2DM history (year): Int: 8.69 ± 5.25; Ctr: 9.56 ± 6.02

Mean PPD (mm): Int: 2.66 ± 0.68; Ctr: 2.47 ± 0.57

Inclusion: diagnosed with T2DM for > 1 year, with no change in their diabetic treatment plan in the previous 2 months and with no major diabetic complication. Diagnosed with chronic PD (with a ≥ 1 mm mean CAL with 16 teeth)

Exclusion: (1) the presence of a systemic disease other than diabetes that could influence the course of the periodontal disease; (2) systemic antibiotic administration within the previous 3 months; (3) pregnancy or lactation; (4) refusal to provide written informed consent; (5) had an active infection other than PD; or (6) had received periodontal treatment in the previous 12 months

Int: SRP at baseline and additional subgingival debridement at the 3-month follow-up. SRP was completed within 24 h, using standard rigid periodontal curets and ultrasonic instrumentation (n = 42)

Ctr: no treatment measure or formal OHI until the end of the study (n = 41)

T2DM treatment change: participants were instructed to continue with their medication and lifestyle

D'Aiuto 2018 [11]

Mean age ± SD (years): Int: 58.2 ± 9.7; Ctr: 55.5 ± 10.0

Gender (male/female): Int: 82/51; Ctr: 83/48

Follow-up: 6 months; 12 months

Jadad score: 6

HbA1c level (%): Int: 8.1 ± 1.7; Ctr: 8.1 ± 1.7

T2DM history (year): Int: 8.3 ± 7.4; Ctr: 8.7 ± 8.4

Mean PPD (mm): Int: 3.9 ± 0.7; Ctr: 3.9 ± 0.8

Inclusion: diagnosed with T2DM for > 6 months; with moderatetosevere PD (≥ 20 periodontal pockets with PPD of > 4 mm and marginal alveolar bone loss of > 30%), and at least 15 teeth

Exclusion: with uncontrolled sy0stemic diseases other than diabetes (cardiovascular diseases [including hypertension], liver diseases, pulmonary diseases, end stage renal failure, or neoplasm); hepatitis B or HIV infection; chronic treatment (> 2 weeks) with drugs known to affect periodontal tissues (phenytoin or ciclosporin); chronic systemic antibiotic treatment; pregnancy or lactation

Int: OHI. Extraction of hopeless teeth. Initial single session of whole mouth SRP. After initial SRP, received root scaling every 3 months. Twp months after first SRP, received additional root scaling or periodontal surgery (n = 133)

Ctr: OHI. Extraction of hopeless teeth. Initial single session of whole mouth SGS. After initial SGS, received SGS every 3 months. If SRP were needed, withdrew (n = 131)

T2DM treatment change: mo significant lifestyles or diets changes during study. Medication change was similar between groups during the trail

Engebretson 2013 [9]

USA

Mean age ± SD (years): Int: 56.7 ± 10.5; Ctr: 57.9 ± 9.6

Gender (male/female): Int: 143/114; Ctr: 134/123

Follow-up: 3 months; 6 months

Jadad score: 6

HbA1c level (%): Int: 7.84 ± 0.65; Ctr: 7.78 ± 0.60

T2DM history (year): Int: 12.3 ± 8.2; Ctr: 11.3 ± 8.4

Mean PPD (mm): Int: 3.28; Ctr: 3.26

Inclusion: age > 35 years.; diagnosed with T2DM of > 3 months HbA1c between 7.0 to 9.0%; no changes in diabetes medications within the last 3 months; not pregnant; diagnosed with moderate to advanced PD (CAL and PPD > 5 mm in ≥ 2 quadrants); at least 16 natural teeth; n periodontal treatment in the prior 6 months

Exclusion criteria: limited life expectancy; diabetes related emergency within 30 days; use of nonsteroidal anti-inflammatory drugs other than daily low-dose aspirin; use of immune-suppressive medications; antibiotic use (> 7 days within 30 days of enrollment); dialysis; risk of bleeding complications; or heavy alcohol consumption

Int: SRP for > 160 min using curettes and ultrasonic instruments during ≥ 2 sessions completed within 42 days of the baseline visit. OHI after treatment. Used mouthwash twice daily for 2 weeks. Three and 6 months after the baseline visit, SRP and OHI were given during a single session (n = 257)

Ctr: OHI at the baseline and 3- and 6-month visits. Following their 6-month visit, SRP were given (n = 257)

T2DM treatment change: participants agreed to not change diabetes medications during the trial unless medically indicated. Medication change was similar between groups during the trail

Fu 2014 [17]

China

Mean age (years): 58.6 (range 40–67)

Gender (male/female): 67/53

Follow-up: 6 months

Jadad score: 1

HbA1c level (%):

Int: 9.46 ± 1.21; Ctr: 9.53 ± 1.14

T2DM history (year): NA

Mean PPD (mm): Int: 5.73 ± 0.39; Ctr: 5.77 ± 0.44

Inclusion: diagnosed with T2DM and PD

Exclusion: with uncontrolled systemic diseases other than diabetes

Int: SRP. Used mouthwash and oral antibiotics pre- and post-SRP. Details of SRP were NA (n = 60)

Ctr: None (n = 60)

T2DM treatment change: both groups received standard T2DM treatment, including diet, exercise, and insulin (details NA)

Fu 2014 [18]

China

Mean age ± SD (years): Int: 51.6 ± 3.8; Ctr: 50.3 ± 3.9

Gender (male/female): Int: 17/14; Ctr: 15/16

Follow-up: 3 months

Jadad score: 1

HbA1c level (%): Int: 9.88 ± 0.86; Ctr: 9.91 ± 0.78

T2DM history (year): Int: 3.35 ± 1.43; Ctr: 3.21 ± 1.32

Mean PPD (mm): Int: 5.76 ± 0.51; Ctr: 5.68 ± 0.47

Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 3 months; with PD (≥ 6 sites with PPD of > 4 mm and CAL of > 4 mm), and at least 15 teeth

Exclusion: with uncontrolled systemic diseases other than diabetes; with sever diabetes complications; chronic systemic antibiotic treatment

Int: SRP. Used oral antibiotics pre- and post-SRP (roxithromycin, 0.2 g qid; metronidazole, 0.4 g tid). Details of SRP were NA (n = 31)

Ctr: None (n = 31)

T2DM treatment change: both groups received standard T2DM treatment, including oral repaglinide (1 mg tid) and metformin (0.5 g tid)

Gu 2011 [19]

China

Age (year): 60–70

Gender (male/female): 38/22

Follow-up: 6 months

Jadad score: 4

HbA1c level (%): Int: 9.46 ± 1.21; Ctr: 9.53 ± 1.14

T2DM history (year): NA

Mean PPD (mm): Int: 5.94 ± 1.02; Ctr: 6.08 ± 0.92

Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication recently; baseline HbA1c level between 8 and 12%; without systemic diseases other than diabetes; with PD (≥ 6 sites with PPD of > 5 mm); radiograph showed multiple teeth showed alveolar bone loss of > 1/3 of root; at least 15 teeth; did not use antibiotics in the last 3 months; did not receive periodontal therapy in last 6 months

Int: OHI. Extraction of hopeless teeth. SRP. Used mouthwash for 2 weeks post SRP. Details of SRP were NA (n = 30)

Ctr: None (n = 30)

T2DM treatment change: participants did not change diabetes medications during the trial

Hao 2016 [20]

China

Mean age ± SD (years): Int: 61.06 ± 10.26; Ctr: 63.59 ± 8.97

Gender (male/female): Int: 18/11; Ctr: 16/14

Follow-up: 3 months

Jadad score: 1

HbA1c level (%): Int: 9.07 ± 1.54; Ctr: 9.21 ± 1.59

T2DM history (year): Int: 7.65 ± 5.33; Ctr: 6.85 ± 4.67

Mean PPD (mm): Int: 4.12 ± 0.70; Ctr: 4.05 ± 0.63

Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 2 months; with PD (≥ 2 teeth with PPD of > 5 mm and CAL of > 2 mm), and at least 16 teeth

Exclusion: with uncontrolled systemic diseases other than diabetes; with severe diabetes complications; antibiotic use (> 7 days within 30 days of enrollment); received periodontal therapy in last 6 months; pregnancy or lactation

Int: OHI and SRP. Details of SRP were NA (n = 30)

Ctr: None (n = 30)

T2DM treatment change: both groups received standard T2DM treatment, including diet, exercise, and medications (details NA)

Katagiri 2009 [21]

Japan

Mean age ± SD (years): Int: 60.3 ± 9.9 Ctr: 59.0 ± 4.8

Gender (male/female): Int: 21/11; Ctr: 6/11

Follow-up: 3 months; 6 months

Jadad score: 2

HbA1c level (%): Int: 7.2 ± 0.9; Ctr: 6.9 ± 0.9

T2DM history (year): Int: 11.3 ± 6.4; Ctr: 8.8 ± 7.5

Mean PPD (mm): Int: 3.0 ± 0.9; Ctr: 2.8 ± 0.9

Inclusion: age between 39–75 years, HbA1c between 6.5–10.0%; without severe diabetic complications; no evidence of systemic diseases; no systemic antibiotics during the preceding 3 months; no pregnancy or lactation; no allergy to tetracycline; no smoking; and no modifications in the treatment of diabetes in last 2 months; at least 11 teeth, with PD (≥ 2 teeth with PPD of > 4 mm); no periodontal treatment in last 6 months

Int: SRP was done using ultrasonic instrumentation. The SRP was completed over the course of four visits within 2 months. 10 mg of minocycline ointment was administered topically in every periodontal pocket at the end of each visit. OHI (n = 32)

Ctr: OHI (n = 17)

T2DM treatment change: the doses and kinds of anti-diabetic drugs, and methods of diet and exercise were not changed

Kaur 2015 [22]

India

Mean age ± SD (years): Int: 51.82 ± 5.85; Ctr: 52.94 ± 6.03

Gender (male/female): Int: 22/28; Ctr: 26/24

Follow-up: 3 months; 6 months

Jadad score: 2

HbA1c level (%): (a): Int: 6.03 ± 0.47 Ctr: 5.94 ± 0.75 (b): Int: 9.99 ± 2.02 Ctr: 9.81 ± 2.24

T2DM history (year): Int: 8.57 ± 6.39; Ctr: 7.05 ± 4.43

Mean PPD (mm): (a): Int: 2.82 ± 0.44 Ctr: 2.92 ± 0.58 (b): Int: 3.08 ± 0.45 Ctr: 3.23 ± 0.48

Inclusion: diagnosed with T2DM for > 12 months; no change in T2DM medication use during the 2 months before the study or during the study; age between 45 and 60 years; presence of ≥ 12 teeth (excluding third molars); diagnosed as moderate (> 2 sites with CAL > 4 mm and > 1 site with PPD > 4 mm) or severe (> 2 sites with CAL > 6 mm and > 1 site with PPD > 5 mm) generalized chronic PD

Exclusion: had systemic disease that could influence the course of periodontal disease; pregnant or lactating; current or ex-smokers; major diabetic complications; a history of systemic antibiotic use within the previous 3 months or periodontal treatment during the previous 6 months

Int: OHI. Four SRP sessions over a maximum of 2 weeks, using Gracey curettes and an ultrasonic scaler. Additional supportive SRP was done when necessary (n = 50)

Ctr: None (n = 50)

T2DM treatment change: no change in T2DM medication use during the 2 months before the study or during the study

Kiran 2005 [23]

Turkey

Age (year): Int: 55.95 ± 11.21; Ctr: 52.82 ± 12.27

Gender (male/female): Int: 10/12; Ctr: 8/14

Follow-up: 3 months

Jadad score: 1

HbA1c level (%): Int: 7.31 ± 0.74; Ctr: 7.00 ± 0.72

T2DM history (year): Int: 9.32 ± 8.36; Ctr: 8.05 ± 5.90

Mean PPD (mm): Int: 2.29 ± 0.49; Ctr: 2.24 ± 0.70

Inclusion: diagnosed with T2DM with HbA1c values between 6 and 8%; creatinine values < 1.4 mg/dl; liver function tests were not up to threefold the normal range; no major diabetic complications; no history of systemic antibiotic administration within the last 3 months; no periodontal treatment 6 months prior to the study

Int: OHI and SRP. 9 patients had 9 teeth with periapical lesions. 4 teeth were extracted and 5 had root canal treatment (n = 22)

Ctr: OHI. 5 patients had 5 teeth with periapical lesions where they received root canal treatment (n = 22)

T2DM treatment change: no change in the medication or diet was made for both groups during the study period. None of the groups received any additional guidance in managing their diabetic status

Li 2011 [24]

China

Mean age ± SD (years): Int: 58.7 ± 10.73; Ctr: 62.4 ± 9.18

Gender (male/female): Int: 51/39; Ctr: 19/26

Follow-up: 3 months; 6 months

Jadad score: 1

HbA1c level (%): Int: 7.33 ± 1.37; Ctr: 7.25 ± 1.54

T2DM history (year): NA

Mean PPD (mm): Int: 2.48 ± 0.56; Ctr: 2.62 ± 0.68

Inclusion: diagnosed with T2DM for > 12 months and did not change T2DM medication in last 2 months; with PD and at least 15 teeth; no periodontal treatment in last 12 months; did not use antibiotics in the last 3 months

Exclusion: with systemic diseases other than diabetes; with severe diabetes complications; with acute infection; pregnancy or lactation

Int: OHI. Extraction of hopeless teeth. SRP at baseline and additional SRP at the 3-month follow-up. First SRP was done within 24 h (n = 90)

Ctr: OHI (n = 45)

T2DM treatment change: NA

Makaky 2019 [25]

Egypt

Mean age ± SD (years): Int: 52.95 ± 6.523; Ctr: 52.23 ± 7.028

Gender (male/female): Int: 18/26; Ctr: 20/24

Follow-up: 3 months

Jadad score: 4

HbA1c level (%): Int: 8.12 ± 0.74; Ctr: 8.21 ± 0.71

T2DM history (year): NA

Mean PPD (mm): Int: 4.99 ± 0.75; Ctr: 5.01 ± 0.83

Inclusion: diagnosed with T2DM for > 5 years with HbA1c level from 7 to 9%; no change in diabetes treatment over the previous 3 months; diagnosis with chronic PD (> 4 teeth with one site with a CAL > 3 mm and PPD > 4 mm); 30% sites with CAL and pocket depth PD > 4 mm; at least 6 teeth; age from 40 to 70 years

Exclusion: pregnancy; alcoholism and smoking; presence of any systemic disorders other than hypertension and T2DM; with T2DM major complications; antimicrobial therapies in the last 6 months; periodontal therapies in the last 6 months; allergy to metronidazole and amoxicillin

Int: OHI. SRP using ultrasonic apparatus in a single 2-h session. After SRP, using systemic antibiotics for 2 weeks (metronidazole 400 mg tid and amoxicillin 500 mg tid) (n = 44)

Ctr: None (n = 44)

T2DM treatment change: NA

Mauri-Obradors 2018 [26]

Spain

Mean age ± SD (years): Int: 61 ± 11; Ctr: 62 ± 10

Gender (male/female): Int: 17/25; Ctr: 20/28

Follow-up: 6 months

Jadad score: 4

HbA1c level (%): Int: 7.65; Ctr: 7.75

T2DM history (year): Int: 10; Ctr: 11

Mean PPD (mm): Int: 3.5; Ctr: 3.0

Inclusion: diagnosed with T2DM for > 1.5 years; with generalized chronic PD (> 9 teeth present and > 30% of the sites with a PPD and CAL > 4 mm)

Exclusion: antibiotic treatment during the previous 15 days or for periods > 10 days during the last 3 months; SRP within the past 6 months; pregnancy; significant changes in diabetes medication during the course of the study; with other serious systemic disease

Int: OHI and SRP. Additional SRP when needed (n = 36)

Ctr: OHI and SGS. (n = 44)

T2DM treatment change: patients had significant changes in diabetes medication during the course of the study were excluded

Mizuno 2017 [27]

Japan

Mean age ± SD (years): Int: 61.2 ± 9.2; Ctr: 62.8 ± 12.1

Gender (male/female): Int: 13/7; Ctr: 15/2

Follow-up: 3 months; 6 months

Jadad score: 5

HbA1c level (%): Int: 7.5 ± 1.7; Ctr: 7.7 ± 1.2

T2DM history (year): NA

Mean PPD (mm): Int: 2.4 ± 0.5; Ctr: 2.4 ± 0.7

Inclusion: diagnosed with T2DM for > 2 months; diagnosed with mild to advanced chronic PD (> 2 sites with CAL > 3 mm and PPD > 4 mm or 1 site with PPD > 5 mm); age > 30 years

Exclusion: pregnancy; inappropriate status for the trials, such as limited life expectancy and diabetes-related emergency; received periodontal treatment in the prior 6 months

Int: at the baseline visit, receive OHI and one session SGS. Within 42 days after the baseline visit, receive SRP (2–3 sessions, each time > 60 min) using curettes and an ultrasonic instrument (n = 20)

Ctr: At the baseline visit, receive OHI and one session SGS (n = 17)

T2DM treatment change: of the 30 participants with medication data available, both groups had no protocol defined changes during the study

Moeintaghavi 2012 [28]

Iran

Mean age ± SD (years): 50.29 ± 3

Gender (male/female): Int: 9/13; Ctr: 11/7

Follow-up: 3 months

Jadad score: 6

HbA1c level (%): Int: 8.15 ± 1.18; Ctr: 8.72 ± 2.22

T2DM history (year): NA

Mean PPD (mm): Int: 2.31 ± 0.65; Ctr: 2.06 ± 0.24

Inclusion: diagnosed with T2DM with HbA1c over 7%, and no major diabetic complications; using glibenclamide and metformin, without insulin administration for T2DM; no systemic antibiotic administration or periodontal treatment within the last 6 months; diagnosed with mild to moderate PD

Exclusion: presence of systemic diseases other than T2DM that could influence the course of PD; intake of immunosuppressive drugs, steroids, hydantoin or non-steroidal anti-inflammatory drugs; tobacco use; pregnancy or intention to become pregnant during the study period; fixed orthodontic appliances

Int: OHI and extraction of unsalvageable teeth. Then SRP by using an ultrasonic device and standard periodontal curettes with no time limitation. No additional periodontal therapy was given (n = 22)

Ctr: OHI and extraction of unsalvageable teeth (n = 18)

T2DM treatment change: all patients were under strict medical supervision and, as a prerequisite, no additional guidance in managing diabetic status or changes in diet, medication or physical therapy was given

Raman 2014 [29]

Malaysia

Age (year):

Int: 57.7 ± 9.9; Ctr: 54.6 ± 6.2

Gender (male/female):

Int: 11/4; Ctr: 9/8

Follow-up: 3 months

Jadad score: 5

HbA1c level (%):

Int: 7.8 ± 1.5; Ctr: 7.6 ± 1.5

T2DM history (year):

Mean PPD (mm):

Int: 2.56 ± 0.57; Ctr: 2.29 ± 0.69

Inclusion: diagnosed with T2DM; diagnosed with moderate to advanced chronic PD, with at least 12 teeth present and with 5 or more sites of PPD > 5 mm and CAL > 4 mm in at least 2 different quadrants which bled on probing

Exclusion: a history of systemic antibiotic usage over the previous 4 months; having received non-surgical periodontal treatment within the past 6 months or surgical periodontal treatment within the past 12 months; pregnancy; change of medication for diabetes during the course of the study; current smoker; or history of a cerebrovascular or cardiovascular event within the past 12 months

Int: OHI. SRP in a single visit using an ultrasonic scaler and Gracey curretes. 0.12% chlorhexidine mouthrinse (tid, 14 days) after SRP (n = 15)

Ctr: OHI (n = 17)

T2DM treatment change: participants who changed medication for diabetes during the course of the study were excluded

Singh 2008 [30]

India

Age (years): NA

Gender (male/female): NA

Follow-up: 3 months

Jadad score: 1

HbA1c level (%):

Int: 7.9 ± 0.7; Ctr: 8.08 ± 0.7

T2DM history (year):

Mean PPD (mm):

Int: 2.67 ± 0.35; Ctr: 2.44 ± 0.26

Inclusion: diagnosed with T2DM; no major diabetic complications; no systemic diseases other than T2DM that could influence the course of PD; with moderate to advanced PD (> 30% of the teeth with a PPD > 4 mm)

Exclusion: with uncontrolled T2DM; less than 16 teeth; had systemic antibiotic administration in last 3 months; had periodontal treatment in last 6 months

Int: Extraction of hopeless teeth and SRP (n = 15)

Ctr: Extraction of hopeless teeth (n = 15)

T2DM treatment change: no change of medication and diet was modified for the participants

Telgi 2013 [31]

India

Mean age ± SD (years): NA

Gender (male/female): NA

Follow-up: 3 months

Jadad score: 1

HbA1c level (%): Int: 7.68 ± 0.63; Ctr: 7.56 ± 0.59

T2DM history (year): NA

Mean PPD (mm): Int: 5.05 ± 0.70; Ctr: 5.11 ± 0.57

Inclusion: diagnosed with T2DM; blood sugar controlled only with oral hypoglycemic agents; mild to moderate PD (PPD of 4–5 mm); presence of a minimum of 28 teeth; and no systemic antibiotic administration and no periodontal treatment in last 6 months

Exclusion: patients with systemic diseases other than T2DM; tobacco and alcohol user; and suffering from oral disease that needed emergency treatment

Int: SRP. OHI and regularly used 0.12% chlorhexidine mouthwash (qd) (n = 15)

Ctr: OHI and regularly used 0.12% chlorhexidine mouthwash (qd) (n = 15)

T2DM treatment change: NA

Tsobgny-Tsague 2018 [32]

Cameroon

Mean age ± SD (years): Int: 51.2 ± 7.8; Ctr: 51.7 ± 9.9

Gender (male/female): Int: 8/7; Ctr: 5/10

Follow-up: 3 months

Jadad score: 5

HbA1c level (%): Int: 9.7 ± 1.6; Ctr: 8.9 ± 0.9

T2DM history (year): Int: 5.0 ± 3.86; Ctr: 4.26 ± 3.3

Mean PPD (mm): Int: 3.0 ± 0.4; Ctr: 3.1 ± 0.6

Inclusion: poorly controlled T2DM, with moderate to severe chronic PD, and having at least 11 teeth in the mouth

Exclusion: periodontal treatment; alteration in diabetes treatment 6 months prior to the study; onset of systemic diseases or an acute condition; use of immunosuppressive medications or other drugs; or presence of conditions able to alter PD clinical features (pregnant women, alcohol users, smokers and acute anemia)

Int: OHI. A single SRP using ultrasonic device and Gracey’s curettes. Chlorhexidine gluconate 0.2% as mouth wash (10 ml bid for 5 days) (n = 15)

Ctr: OHI (n = 15)

T2DM treatment change: NA

Wang, J 2013 [33]

China

Mean age ± SD (years): 35–74

Gender (male/female): 32/43

Follow-up: 3 months

Jadad score: 1

HbA1c level (%): Int: 7.57 ± 1.62; Ctr: 7.73 ± 1.74

T2DM history (year): 7.68 ± 1.37

Mean PPD (mm): Int: 4.21 ± 0.65; Ctr: 4.01 ± 0.73

Inclusion: diagnosed with T2DM and PD

Exclusion: received periodontal treatment in last 6 months; defective prosthesis; edentulous; with severe diseases other than diabetes; mental disorders; use of antibiotics or steroids in last 6 months

Int: OHI. Initial single session of whole mouth SGS using ultrasonic instrumentation. After 1 week received SRP and took oral antibiotics (amoxicillin and metronidazole) for 3 days (n = 37)

Ctr: None (n = 38)

T2DM treatment change: NA

Wang 2017 [34]

China

Mean age ± SD (years): Int: 61.2 ± 9.2; Ctr: 61.90 ± 6.75

Gender (male/female): Int: 12/7; Ctr: 14/6

Follow-up: 3 months

Jadad score: 3

HbA1c level (%): Int: 7.63 ± 0.89; Ctr: 7.67 ± 1.32

T2DM history (year): Int: 8.47 ± 3.08; Ctr: 7.70 ± 4.69

Mean PPD (mm): Int: 3.66 ± 0.60; Ctr: 3.85 ± 0.58

Inclusion: diagnosed of T2DM for > 12 months with HbA1c from 6.5–10.0%; with chronic PD (more than 30% of teeth with PPD ≥ 5 mm and CAL > 4 mm, or > 60% of teeth with PPD > 4 mm and CAL ≥ 3 mm); at least 15 remaining teeth; body mass index < 30; without periodontal treatment in the previous 6 months; without antibiotic or NSAIDs administration in the 3 months; without serious systemic diseases or complications

Int: OHI and SRP. Also received extraction of hopeless teeth, and the restoration of balanced occlusion (n = 19)

Crt: None (n = 20)

T2DM treatment change: to guard against the effects of the periodontal intervention on glycemic control and adipokines, no changes in medications or diet were made for any subject during the study period

Zhang 2013 [35]

China

Mean age ± SD (years): Int: 60.4 ± 9.77; Ctr: 62.7 ± 10.7

Gender (male/female): Int: 21/28; Ctr: 10/12

Follow-up: 3 months

Jadad score: 4

HbA1c level (%): Int: 7.68 ± 1.22; Ctr: 7.38 ± 1.30

T2DM history (year): Int: 8.63 ± 4.20; Ctr: 7.29 ± 5.61

Mean PPD (mm): Int: 2.50 ± 0.45; Ctr: 2.43 ± 0.47

Inclusion: diagnosed to have T2DM > 1 year with HbA1c > 5.5%; diagnosed with chronic PD (at least 4 teeth with PPD > 5 mm, CAL > 4 mm, and bleeding on probing distributed in n > 2 quadrants); at least 16 teeth; age 35–80 years

Exclusion: accompanied with other systemic immune diseases; administered with antibiotics, immunomodulators, contraceptives, or any other form of hormone within the past 3 months; underwent modified T2DM treatment strategy within 3 months; had periodontal treatment within the past 12 months; needed extraction or endodontic treatment; smokers; pregnant or lactating women

Int: OHI and SRP (including manual curettage). SRP were completed within 2 weeks after the baseline evaluation (n = 49)

Ctr: None (n = 22)

T2DM treatment change: the recruited patients were instructed to maintain their previous diet and exercise habits and to inform the authors whenever their glucose control treatment was changed. Patients were dropped from the study if their diabetes treatment scheme was changed

CAL clinical attachment loss, Ctr: control group, Int: intervention group, HbA1c glycosylated hemoglobin, HIV human immunodeficiency virus, NA not available, NSAIDs nonsteroidal anti-inflammatory drugs, OHI oral hygiene instruction, PD periodontitis, PPD pocket probing depth, qid four time a day, SD standard deviation SGS supragingival scaling, SRP scaling and root planing,T2DM type 2 diabetes mellitus, tid three times a day