Periodontal Disease in Down Syndrome: A Systematic Review and Meta-analysis

Objectives: The aim was to search for scientific evidence of the association between periodontal disease (PD) in individuals with down syndrome (DS), compared to normal individuals.
Methods: The clinical question was: (P: individuals at any age; E: DS; C: normal individuals; O: PD) (PROSPERO CRD42015025490). An electronic search was conducted in seven databases until March 2016 and a manual search was also conducted. Two independent reviewers selected studies, extracted data and assessed risk of bias by a modified Newcastle-Ottawa scale. Meta-analysis was performed; it was calculated odds ratio (OR) for dichotomous outcomes of periodontal parameters, and standard mean difference (SMD) for continuous ones; 95% CI was estimated. Statistical heterogeneity was performed by the I² test.
Results: Twenty one case-control studies were included in the systematic review (7 included in the meta-analysis). Studies’ quality ranged from 4 to 9 points (total 10 points), and several studies had high risk of bias. Several periodontal parameters were used for periodontal diagnosis, featuring a high clinical heterogeneity. The meta-analysis showed a significant association between PD and individuals with DS for the clinical parameters: probing depth> 5 mm (OR = 3.63, 95% CI 1.71 to 7.72, I² = 0.0%); Oral Hygiene index (SMD = 0.36, 95% CI -0.5 to 0.78, I² = 0.0%); bleeding on probing (SMD = 0.78, 95% CI 0.48 to 1.08, I² = 0.0%). However the probing depth>4mm (OR= 2.92, 95% CI 0.62 to 13.70, I² = 62.98) and plaque index (SMD = 4.10, 95% CI 3.06 to 5.14, I² = 62.97) had no significant difference.
Conclusions: The scientific evidence suggests that the occurrence of some parameters periodontal is higher in individuals with DS compared with normal individuals.