Oral health status for primary dentition – A pilot study : Journal of Indian Society of Pedodontics and Preventive Dentistry (2025)

Introduction

Oral hygiene index (OHI) found in 1960 by Greene and Vermillion[¹] is a sensitive, simple method for assessing group or individual oral hygiene quantitatively. Simplified OHI (OHI-S) was introduced in 1964[²] to reduce the number of decisions required on the part of the examiner and the time required for the inspection. OHI-S differs from OHI in the number of tooth surfaces involved (6 rather than 12), method of selecting the surfaces to be scored and the scores which can be obtained. OHI-S, similar to OHI, has two components such as Simplified Debris Index (DI-S) and the Simplified Calculus Index (CI-S). Neither of these indices (OHI or OHI-S) mention the index teeth to be recorded in primary dentition; hence, it is essential to formulate an OHI-S for the primary dentition (OHI-S). Formulating an oral health status which will include the OHI exclusively for children will make it easier for the examiner to assess the current oral hygiene status of the child and help in planning preventive strategies. This index will provide a comprehensive yet quick way to assess the oral hygiene status of children.

Suomi et al. 1971[³] found that younger children have lesser calculus than older children and adults. There is a gradual increase in amounts of calculus with advancing age. Hence, CI need not be necessarily included for OHI-S in the primary dentition.

Considering the difference in clinical features of gingiva and periodontal tissue in primary teeth and permanent teeth, OHI-S exclusively for primary dentition is necessary. The need for OHI-S in primary dentition is indicated to determine the children's level of oral cleanliness and to determine the appropriate age at which preventive procedures for periodontal disease can be started. This oral hygiene status also includes the defs index given by Gruebbel A. O (1944) to give us the past caries experience of the child and the incidence of white spot lesions (WSL) classified by Gorelick et al. (1982), which gives us the prediction of a future caries experience, as WSLs are a clinical manifestation of early enamel caries. This cumulative index giving the oral health status of children can be widely used in studies of epidemiology and evaluation of dental health education programs in public school systems. Hence, the aim of this study is to introduce a new and simplified oral health status exclusively for primary teeth.

Materials and Methods

Study design and setting

The study setting is a university-based single-centered study and was conducted in a private dental college in Chennai, India. Ethical approval was obtained from the Institutional Review Board, Saveetha Institute of Medical and Technical Sciences. This study has internal and external validity.

Data collection

Two hundred children aged 3–5 years (primary dentition) were included in this study. Oral hygiene index tooth wise and sextant wise, deft index and the presence of white spot lesions were recorded for each patient [Figure 1].

Deft/defs index - Past caries experience

Deft index given by Gruebbel A. O in 1944 is equivalent to the dimethylformamide index in adults. It was recorded in each subject for all the 20 teeth. This gives us the past caries experience.

• d = decayed teeth
• e = extracted teeth (extracted or lost due to caries only; exfoliated teeth not included)
• f = filled teeth.

Missing primary incisors should not be scored as missing because of the difficulty in differentiating between normally exfoliated primary incisors and those lost because of caries or trauma. If it can be accurately established that a missing deciduous tooth has been lost due to caries only, then it is included in the “e” component for primary teeth; the maximum deft score for an individual would be 20.

Simplified oral hygiene index for primary teeth – Present status

In this study, OHI was assessed segment wise as developed by Greene and Vermillion in 1960 by dividing the primary dentition into six segments and scoring only the tooth with the greatest area covered by debris from each segment. The calculus score was not recorded.

It was also assessed index tooth wise; DI was recorded for the following index teeth.

• Labial surface of 54 and 64
• Labial surface of 61
• Lingual surface of 82
• Lingual surface of 75 and 85.

If any of the above index teeth were missing or exfoliated, the adjacent tooth of the same segment was considered.

Scoring and interpretation

The score for each tooth recorded was calculated based on the DI, which is a part of the OHI (OHI; 1960).

• Score varies from 0 to 3
• Score 0 – No debris present
• Score 1 – Soft debris covering not more than one-third of the tooth surface
• Score 2 – Soft debris covering more than one-third but not more than two-third of the exposed tooth surface
• Score 3 – Soft debris covering more than two-third of the exposed tooth surface.

Buccal total score + lingual total score/number of segments scored.

Interpretation

• Good – 0–1.2
• Fair – 1.3–3.0
• Poor – 3.1–6.0.

White spot lesions: Future prediction

WSLs were recorded for all the 20 teeth [Figure 1] based on the classification given by Gorelick et al. (1982).[⁴]

• Class 1 – No WSL formation
• Class 2 – Mild WSL present
• Class 3 – Severe WSL present
• Class 4 – Cavitation is present in addition to WSL.

Statistical analysis

All the statistical analyses were carried out using IBM SPSS version 23.0 IBM Corporation, NY, USA.

The receiver operating characteristics (ROC) curve was used to evaluate the accuracy of recording OHI in children index tooth wise and segment wise [Figure 2].

Results

All the three indices were recorded for the 200 subjects, and based on the area under the curve of the ROC, it was found that the OHI for primary dentition can be recorded tooth wise or segment wise.

Simplified oral hygiene index for primary teeth

Index teeth chosen for primary dentition were labial surfaces of 54, 61, and 64 and lingual surfaces of 82, 75, and 85.

Alternate teeth if index teeth missing:

• 54–55
• 61–51
• 64–65
• 82–72
• 75–74
• 85–84.

To make this a cumulative index, the deft index was recorded in all 20 primary teeth, and WSLs classified by Gorelick et al. were noted for all the 20 teeth as well. A final score cannot be given as all the above-mentioned indices and classification record completely different data which cannot be added or calculated together.

A model similar to the cardiogram pie chart is proposed in this study [Figure 3] to evaluate all the above mentioned criteria in an easier way.[⁵]

Discussion

This pilot study, including 200 children (100 male, 100 female) aged 3–5 years, was conducted to evaluate the oral health status of children in a simple yet effective way. OHI-S exclusively for primary dentition is necessary. The need for OHI-S in the primary dentition (OHI-s) is indicated to determine the children's level of oral cleanliness and to determine the appropriate age at which preventive procedures for periodontal disease can be started. This study also includes the defs index given by Gruebbel A. O (1944) to give us the past caries experience of the children and the incidence of WSLs classified by Gorelick et al. (1982)[⁴] which gives us the prediction of a future caries experience as WSLs are a clinical manifestation of early enamel caries.

The original OHI was depicted as “a sensitive, simple method for assessing group or individual oral hygiene quantitatively.”[¹] After considerable trial and error, to overcome the drawbacks, as it took the user to make more decisions and to spend more time in arriving at his/her evaluation, another index was developed, named OHI-S.[¹²] Nevertheless, both these indices did not include index teeth or teeth that need to be recorded in the primary dentition.

Deft index was recorded in all 20 teeth in this study to assess the past caries experience. The use of a deft index has been an accepted practice for assessing the prevalence and severity of caries in a population.

WSLs were also recorded in this study to predict future caries experience. WSL is a clinical manifestation of early enamel caries.[⁶] The initial stage of demineralization results in white chalky appearance on the teeth; these are called whitespot lesions (or) incipient lesions (or) surface softened defect.[⁷] WSL implies that there is a subsurface area with mineral loss beneath a relatively intact enamel surface. The appearance of WSL is an optical phenomenon caused by a subsurface tissue loss which exaggerates on drying.[⁸] In this study, assessment of WSLs was carried out through direct assessment and photographic analysis. Early detection and intervention of WSLs can minimize the symptoms associated with Early childhood caries (ECC), thereby halting its progression and other psychological outcomes associated with it.[⁹]

The strengths of this study are that it will help us formulate an OHI exclusively for the primary dentition, and it proposes an oral health status model exclusively for primary dentition. The drawback is the geographic location as the study was conducted only in one educational institute, and the sample size was less.

Further research with a larger sample size is being done as this was just the pilot study. There is the abundant future scope for this topic, as the OHI and OHI-S indices do not mention the index teeth to be recorded for primary dentition.

Conclusion

Within the limitations of this study, it can be concluded that this cumulative index can be widely used in studies of epidemiology and helps in quicker evaluation during dental health programs in public school systems as it includes past caries experience, present hygiene status, and the future prediction of caries making it a wholesome index, as the existing OHI-S index does not mention the index teeth for primary dentition.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References