Full-mouth treatment modalities (within 24 hours) for periodontitis in adults

Periodontitis is a highly prevalent, chronic inflammation that causes damage to the soft tissues and bones supporting the teeth. Conventional treatment is quadrant scaling and root planing (the second step of periodontal therapy), which comprises scaling and root planing of teeth in one quadrant of the mouth at a time, with the four different sessions separated by at least one week. Alternative protocols for anti-infective periodontal therapy have been introduced to help enhance treatment outcomes: full-mouth scaling (subgingival instrumentation of all quadrants within 24 hours), or full-mouth disinfection (subgingival instrumentation of all quadrants in 24 hours plus adjunctive antiseptic). We use the older term 'scaling and root planing' (SRP) interchangeably with the newer term 'subgingival instrumentation' in this iteration of the review, which updates one originally published in 2008 and first updated in 2015.

To evaluate the clinical effects of full-mouth scaling or full-mouth disinfection (within 24 hours) for the treatment of periodontitis compared to conventional quadrant subgingival instrumentation (over a series of visits at least one week apart) and to evaluate whether there was a difference in clinical effects between full-mouth disinfection and full-mouth scaling.

An information specialist searched five databases up to 17 June 2021 and used additional search methods to identify published, unpublished and ongoing studies.

We included randomised controlled trials (RCTs) lasting at least three months that evaluated full-mouth scaling and root planing within 24 hours, with or without adjunctive use of an antiseptic, compared to conventional quadrant SRP (control). Participants had a clinical diagnosis of (chronic) periodontitis according to the International Classification of Periodontal Diseases from 1999. A new periodontitis classification was launched in 2018; however, we used the 1999 classification for inclusion or exclusion of studies, as most studies used it. We excluded studies of people with systemic disorders, taking antibiotics or with the older diagnosis of 'aggressive periodontitis'.

Several review authors independently conducted data extraction and risk of bias assessment (based on randomisation method, allocation concealment, examiner blinding and completeness of follow-up). Our primary outcomes were tooth loss and change in probing pocket depth (PPD); secondary outcomes were change in probing attachment (i.e. clinical attachment level (CAL)), bleeding on probing (BOP), adverse events and pocket closure (the number/proportion of sites with PPD of 4 mm or less after treatment). We followed Cochrane's methodological guidelines for data extraction and analysis.

We included 20 RCTs, with 944 participants, in this updated review. No studies assessed the primary outcome tooth loss. Thirteen trials compared full-mouth scaling and root planing within 24 hours without the use of antiseptic (FMS) versus control, 13 trials compared full-mouth scaling and root planing within 24 hours with adjunctive use of an antiseptic (FMD) versus control, and six trials compared FMS with FMD. Of the 13 trials comparing FMS versus control, we assessed three at high risk of bias, six at low risk of bias and four at unclear risk of bias. We assessed our certainty about the evidence as low or very low for the outcomes in this comparison. There was no evidence for a benefit for FMS over control for change in PPD, gain in CAL or reduction in BOP at six to eight months (PPD: mean difference (MD) 0.03 mm, 95% confidence interval (CI) -0.14 to 0.20; 5 trials, 148 participants; CAL: MD 0.10 mm, 95% CI -0.05 to 0.26; 5 trials, 148 participants; BOP: MD 2.64%, 95% CI -8.81 to 14.09; 3 trials, 80 participants). There was evidence of heterogeneity for BOP (I² = 50%), but none for PPD and CAL. Of the 13 trials comparing FMD versus control, we judged four at high risk of bias, one at low risk of bias and eight at unclear risk of bias. At six to eight months, there was no evidence for a benefit for FMD over control for change in PPD or CAL (PPD: MD 0.11 mm, 95% CI -0.04 to 0.27; 6 trials, 224 participants; low-certainty evidence; CAL: 0.07 mm, 95% CI -0.11 to 0.24; 6 trials, 224 participants; low-certainty evidence). The analyses found no evidence of a benefit for FMD over control for BOP (very low-certainty evidence). There was no evidence of heterogeneity for PPD or CAL, but considerable evidence of heterogeneity for BOP, attributed to one study. There were no consistent differences in these outcomes between intervention and control (low- to very low-certainty evidence). Of the six trials comparing FMS and FMD, we judged two trials at high risk of bias, one at low risk of bias and three as unclear. At six to eight months, there was no evidence of a benefit of FMD over FMS for change in PPD or gain in CAL (PPD: MD -0.11 mm, 95% CI -0.30 to 0.07; P = 0.22; 4 trials, 112 participants; low-certainty evidence; CAL: MD -0.05 mm, 95% CI -0.23 to -0.13; P = 0.58; 4 trials, 112 participants; low-certainty evidence). There was no evidence of a difference between FMS and FMD for BOP at any time point (P = 0.98; 2 trials, 22 participants; low- to very low-certainty evidence). There was evidence of heterogeneity for BOP (I² = 52%), but not for PPD or CAL. Thirteen studies predefined adverse events as an outcome; three reported an event after FMD or FMS. The most important harm identified was an increase in body temperature. We assessed the certainty of the evidence for most comparisons and outcomes as low because of design limitations leading to risk of bias, and the small number of trials and participants, leading to imprecision in the effect estimates.

The inclusion of nine new RCTs in this updated review has not changed the conclusions of the previous version of the review. There is still no clear evidence that FMS or FMD approaches provide additional clinical benefit compared to conventional mechanical treatment for adult periodontitis. In practice, the decision to select one approach to non-surgical periodontal therapy over another should include patient preference and the convenience of the treatment schedule.