Dental Caries and Risk Factors in Swedish Adolescents about to Start Orthodontic Treatment with Fixed Appliances

The aim of this study is to investigate the caries situation in a group of Swedish adolescents, who were scheduled for orthodontic treatment with fixed appliances.

An age- and gender-matched control group was selected from the same city (Malmö, Sweden). Caries and fillings on smooth surfaces and fillings on occlusal surfaces were diagnosed clinically and caries and fillings on approximal surfaces by bitewings. Numbers of mutans streptococci (MS) and lactobacilli (LB) were analyzed in saliva.

There were no significant differences regarding manifest caries lesions and fillings on smooth surfaces. Numbers of occlusal-filled surfaces (FS) and approximal decayed and filled surfaces were around 10%, but did not differ between the groups. However, 53% had approximal enamel caries lesions in the test group and 46% in the control group. The prevalence of approximal decayed surfaces (DS) and FS was low in both groups, 0.57 ± 1.41 in the test group and 0.65 ± 1.38 in the control group (p > 0.05), i.e., somewhat more DS in the control group (p < 0.05). Most individuals had low/medium counts of cariogenic bacteria in their saliva and less than 10% high counts in both groups.

Most Swedish adolescents who have been scheduled for treatment with fixed appliances appear to have a low-to-medium caries risk nowadays. However, around 10% of all approximal tooth surfaces of premolars/molars had enamel caries and one-third of the individuals had medium/high counts of cariogenic bacteria in their saliva, which may be risk factors for future caries during orthodontic treatment.

Bitewing radiographs are important before starting orthodontic treatment and approximal caries and many cariogenic bacteria may be risk factors for orthodontic treatment.