Is the Caries Assessment Spectrum and Treatment (CAST) index useful for evaluating a large group of children? Moreover, are the results linked to familial factors, such as parental oral health knowledge, education, or socioeconomic status? To learn more, researchers administered the CAST index to hundreds of 6- and 7-year-olds and asked their parents to complete questionnaires.
The investigators found that this index effectively provided information about caries development over a wide range of lesion types. They reported their findings in BMC Oral Health (January 17, 2019).
"The CAST index is suitable for identification of the need for preventive and curative care at the same time," wrote the authors, led by Azadeh Babaei of the community oral health department at Tehran University of Medical Sciences in Iran.
Casting about
The CAST index is based on visual-tactile examination and accounts for caries status ranging from noncavitated to advanced lesions and tooth loss. According to the authors of the current study, other indexes have various limitations. The decayed, missing, and filled permanent teeth (DMFT) and decayed, missing, and filled primary teeth (dmf) indexes do not take into account the consequences of untreated caries, such as pain and infection. The International Caries Detection and Assessment System (ICDAS) index only notes caries before pulp involvement. The PUFA index does not account for noncavitated status.
Reporting on caries with more detail in high-risk communities and on noncavitated lesions is important in the early stages, with ages 6 to 7 years considered ideal since permanent molars erupt then and can be vulnerable to caries, the authors noted. With mean dmft of 5.16 and DMFT of 0.38 reported in 6-year-old Iranian children in a previous study in 2012, the researchers conducted the current study to examine oral health in 6- to 7-year-olds in Tehran using the CAST index and how this related to various familial factors.
The study included 739 children who underwent an oral exam at school performed by clinicians using a disposable dental mirror and probe under artificial light and scored using the CAST index. The index ranges from 0 to 9 (see chart below).
| CAST index codes | ||
| Code | Characteristics | Description |
| 0 | Sound | No visible evidence of a distinct carious lesion is present. |
| 1 | Sealant | Pits and/or fissures are at least partially covered with a sealant material. |
| 2 | Restored | A cavity is restored with an (in)direct restorative material. |
| 3 | Enamel | Distinct visual change in enamel only; a clear caries-related discoloration is visible, with or without localized enamel breakdown. |
| 4 | Dentine | Internal caries-related discoloration in dentine; the discolored dentine is visible through enamel, which may or may not exhibit a visible localized breakdown of enamel. |
| 5 | Dentine | Distinct cavitation into dentine; the pulp chamber is intact. |
| 6 | Pulp | Involvement of pulp chamber, distinct cavitation reaching the pulp chamber, or only root fragments are present. |
| 7 | Abscess/fistula | A pus-containing swelling or pus-releasing sinus tract is related to a tooth with pulpal involvement. |
| 8 | Lost | The tooth has been removed because of dental caries. |
| 9 | Other | Does not correspond to any of the other descriptions. |
For permanent molars, the investigators noted healthy status (codes 0 through 2) in 89.3% to 93.7%. In primary molars, they found dentinal lesions (codes 4 to 5) in 25.3% to 31.2%, pulp involvement (code 6) in 2.9% to 10.5%, and abscess/fistula (code 7) in less than 1%. Primary molars more commonly had serious morbidity (codes 6 and 7) than second ones.
"The consequences of dental caries, including abscess and fistula, were more prevalent in the first and second primary teeth," the authors wrote.
At the same time, they noted the sound condition of the majority of permanent molars and that few had enamel or dentine lesions, but the use of fissure sealant also was not frequent.
Parents of participants also completed a self-administered questionnaire that included the father's and mother's education and nine statements about oral health knowledge, which the researchers later recorded as true or false.
The only familial factor significantly related to CAST score was father's education. Children whose fathers were illiterate or had completed no more than middle school were almost 2.5 times more likely to have a score of 3 or higher than those whose fathers had an academic degree.
It's complicated
Disadvantages of using the CAST index include that it's more complicated than the dmft and DMFT indexes and the process of calibration between two examiners was time-consuming, although using a visual guide with information on the index and coding was helpful, the authors noted.
"The advantage of using the CAST index is that it reports a full spectrum of dental caries from sound to pulp involvement, abscess/fistula, and tooth loss as severe consequences of caries," they concluded.
