The effect of fixed appliances on oral malodor from beginning of treatment till 1 year
Springer Science and Business Media LLC -- BMC Oral Health
DOI 10.1186/s12903-016-0174-3
  1. Fixed orthodontic treatment
  2. Halitosis
  3. Oral malodor
  4. Halimeter
  5. Volatile sulfide compounds


Orthodontic appliances can enhance plaque accumulation, and this can cause gingival inflammation. Halitosis of oral origin is associated with microbial metabolism on the tongue and in the saliva, dental plaque, and the amount of volatile sulfide-containing compounds. This study used a Halimeter to investigate fixed orthodontic therapy-associated increases in the oral malodor over a year.


Thirteen orthodontic patients with Angle Class I malocclusions receiving fixed orthodontic therapy formed the study group, and 12 dental students without any dental treatment formed the control group. The Halimeter was used to examine oral malodor by detecting volatile sulfur compounds (VSC). Plaque index (PI), gingival index (GI), and probing pocket depth (PPD) were also measured in both groups. The subjects in the study group had one visit before the orthodontic treatment started and seven visits during orthodontic therapy (1, 3, 5, 7, 9, 11, and 13 months after bonding), while the subjects in the control group had three visits, once per subsequent month.


Oral malodor was significantly increased in the fixed orthodontic treatment group during treatment (p < .05). Increases were also observed in the PI, GI, and PPD measures (p < .05). The results of the control group were stable (p > .05).


Oral malodor increased during fixed orthodontic treatments and reached a critical level 7 months later.