Short-term influence of lingual orthodontic therapy on microbial parameters and periodontal status. A preliminary study.

OBJECTIVE: To perform a preliminary study of the short-term effect of fixed, customized lingual orthodontic appliances on periodontal and microbial parameters. MATERIALS AND METHODS: The sample comprised 20 subjects (6 males and 14 females) with a mean age of 22.3 years +/- 8.6 years. Before (T(0)) and 4 weeks after placement (T(1)) of custom-made lingual appliances on the lower teeth only, plaque index (PI), probing pocket depth (PPD), and bleeding on probing (BOP) were measured. A 16S rRNA-based polymerase chain reaction (PCR) method was used to detect Aggregatibacter actinomycetemcomitans ( Aa ) and Porphyromonas gingivalis ( Pg ) in the crevicular fluid. To compare periodontal parameters on bonded lingual (testing) and unbonded palatal (control) and labial (control) sites between T(0) and T(1), the Wilcoxon test was applied. RESULTS: On the lingual aspects of bonded teeth, a significant increase of BOP (T(0): 23.4 +/- 22.5%; T(1): 46.2 +/- 23.5%; P = .001) and PI (T(0): 0.3 +/- 0.3; T(1): 1.0 +/- 0.7; P = .001) was observed, but no significant changes for PPD (T(0): 2.1 +/- 0.4 mm; T(1): 2.2 +/- 0.3 mm; P = .286) were found. On control sites, no significant changes were recorded for any periodontal parameter. Aa was found in 25% of the patients at baseline (5 subjects) and in 35% of the patients at T(1) (2 additional positive subjects), whereas Pg was found in 5% of the cohort at T(0) and at T(1) (same patient). CONCLUSIONS: Even in the short term, insertion of fixed lingual appliances induced a worsening of periodontal parameters restricted to bonded lingual sites.

Influence of lingual orthodontic therapy on microbial parameters and periodontal status in adults.

Insertion of fixed orthodontic appliances can induce an increase in oral biofilm and thereby cause inflammation of the periodontal tissues. The purpose of this study was to perform a longitudinal analysis of clinical and microbial parameters after insertion of lingual brackets. Bleeding on probing (BOP), plaque index (PI), and pocket probing depth (PPD) were measured in 10 adults (8 females and 2 males, aged 29.0 +/- 4.7 years) who received treatment with custom-made lingual appliances (Incognito/iBraces) before (T0) and 3 months after beginning of treatment (T1). No supportive dental prophylaxis was undertaken. In addition, a 16S rRNA-based polymerase chain reaction (PCR) method was used to detect Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) in the crevicular fluid. A Wilcoxon test was used to compare clinical parameters at the buccal (control) and lingual sites between T0 and T1. At T0, BOP was 12.4 +/- 8.2 per cent, PPD 2.1 +/- 0.3 mm, and PI 0.1 +/- 0.2 at the buccal sites and at T1 14.3 +/- 8.1 per cent, 2.1 +/- 0.2 mm and 0.1 +/- 0.2, respectively. At the lingual sites, BOP was 22.2 +/- 19.0 per cent, PPD 2.3 +/- 0.3 mm, and PI 0.1 +/- 0.2 at T0 and at T1 56.2 +/- 31.6 per cent, 2.9 +/- 0.3 mm, and 1.2 +/- 1.1, respectively. Differences between T0 and T1 were significant for clinical parameters only at the lingual sites. Aa was found in five patients at baseline and in four at T1, whereas Pg was found in one patient at T0 and in two at T1. Insertion of fixed lingual appliances without supportive dental prophylaxis induced a worsening of clinical parameters restricted to the lingual sites, whereas the relative prevalence of Aa and Pg remained unchanged.