Elsevier

Archives of Oral Biology

Volume 57, Issue 2, February 2012, Pages 122-130
Archives of Oral Biology

Timing and sequence of emergence of permanent teeth in the Jordanian population

https://doi.org/10.1016/j.archoralbio.2011.08.014Get rights and content

Abstract

Objectives

Population-specific standards of tooth emergence are essential resources for various fields of clinical and forensic dentistry. To date, such standards have not been provided for the Jordanian population. This study aimed at providing the timing and sequence of emergence of the permanent dentition in the Jordanian population.

Methods and results

Using multistage clustered sampling, 1240 males and 1432 females aged 4–16 years from kindergartens and primary schools in the northern, middle and southern regions of Jordan were examined for emergence of permanent teeth. The subjects were classified into 1-year age groups. For a given tooth, “present” teeth were counted and expressed as a frequency relative to the total of subjects within a given age group. Using Probit regression (SPSS version 16), the median emergence age per tooth was calculated for the total sample and for both genders. No statistically significant differences were detected between sides. In addition, mandibular teeth were generally found to emerge earlier than the corresponding maxillary teeth. However, the difference in mandibular precedence was not statistically significant in all corresponding inter-maxillary tooth pairs. Furthermore, permanent teeth were found to emerge sooner in females than in males although the inter-gender differences were non-statistically significant for first molars and central incisors.

Conclusions

The first standards of timing and sequence of permanent tooth emergence specific to the Jordanian population were provided and found to be consistent with those of Caucasian populations. These standards aid managing patients in paediatric dentistry, planning orthodontic therapy and forensic age estimation.

Introduction

Updated population-specific standards on the timing and sequence of permanent tooth emergence are crucial resources for dentists and auxiliaries working in different fields of clinical dentistry such as paediatrics, orthodontics, oral pathology and surgery as well as forensic odontology. Such standards, which provide the normal age range and sequence of emergence of the permanent dentition, help diagnose untimely developmental odontogenic anomalies and make the decision upon whether to treat or extract badly carious deciduous teeth and whether to provide space maintenance following their extraction. In addition, orthodontists frequently rely on the timing and sequence of permanent tooth emergence to decide when to begin and how to design orthodontic treatment. Furthermore, paediatric dentists, auxiliaries and investigators can refer to these standards, which represent the norms of temporal variation, in diagnosing and studying deviations and problems of tooth emergence in children with craniofacial developmental abnormalities and syndromes. Finally, such standards can find application in dental age estimation in the fields of forensic dental science and police investigations.

A number of biological and environmental factors have been recognised to affect the time and sequence of emergence of the permanent teeth. Biological factors are non-acquired and related to the genetically determined biological variation between individuals such as gender difference,1, 2, 3, 4, 5 ethnic derivation,6, 7, 8, 9, 10 craniofacial growth and craniofacial morphology.11 On the other hand, environmental factors are acquired and non-genetically determined. Examples of some environmental factors that may affect the time and sequence of tooth emergence include fluoride intake,12 caries,12, 13, 14, 15, 16 premature extraction of predecessors,13, 17, 18, 19 physique,20, 21, 22 nutrition,20, 23 socio-economic class24, 25 and secular trends.1, 26, 27

The significance of chronological variation in permanent tooth emergence from one population or ethnic group to another cannot be over-emphasised.6, 7, 8, 9, 10 For example, it has been ascertained that Negros have earlier emergence of permanent teeth than Caucasians.8 Therefore, for valid clinical assessment of the timing and sequence of tooth emergence in a child, it is always recommended that dental practitioners refer to the standards of tooth emergence derived from the population to which that child belongs to. Accordingly, dental investigators all over the world have enriched the literature with studies providing population-specific standards of tooth emergence.1, 2, 3, 4, 5, 6, 7, 9, 28, 29, 30, 31, 32, 33, 34, 35 Whilst a limited number of studies on tooth emergence have been conducted on the Middle Eastern or Arab populations,3, 5, 34 none have reported data for the Jordanian population specifically. For that reason, dentists working in Jordan have still been referring to the standards available in the textbooks of oral anatomy36, 37 (derived from papers reporting old studies conducted on American or British populations) in management of their patients.

The aim of this study was to provide the first standards specific to the Jordanian population on the timing and sequence of emergence of the permanent dentition to act as valid resources for dental clinicians working in Jordan and treating Jordanian children and adolescents. Such standards will be the basis for future studies investigating the timing and sequence of emergence of the permanent dentition in children with various craniofacial developmental abnormalities and syndromes. In addition, the same methodology followed in this study is intended to be re-used for providing the first Jordanian standards on deciduous tooth emergence.

Section snippets

Materials and methods

For this cross-sectional study, data were collected from 2672 school children and adolescents: 1432 females and 1240 males aged 4–16 years. All participants were Jordanian citizens of Arab ancestry. Ethnically, 95–97%a of Jordanians are Caucasoid Arabs who have been living in the region for several generations. Therefore, the subjects of this study are assumed to have common ancestry with minimal ethnical divergence. All the selected participants

Results

Table 1 presents the age groups and the number of subjects per group for the total sample and for both genders.

Testing the differences between sides showed that at the significance level of 0.05 the differences between the median ages at emergence of contra-lateral tooth pairs were non-statistically significant. Therefore, the data were given for the right side only. Table 2 provides the median ages for emergence of the maxillary and mandibular right teeth and the corresponding 5th and 95th

Discussion

In the present study, the selection of subjects did not consider the potential influence of the varying school type or socio-economic class of children on the timing of permanent tooth emergence. The varying school type is believed to be correlated with the socio-economic class of subjects. Private school children are usually expected to belong to a higher socio-economic class than that of governmental or UNRWA school children. Although such influence of the two correlated factors is intended

Acknowledgements

I would like to thank the research assistants: Dr. Mohammed M. Algharram, Dr. Mohammad A. Attieh and Dr. Melanie F. Alazzam, who made the data collection possible in less than 4 months. Also, I would like to acknowledge the financial support of the Deanship of Research/JUST through their grant that covered all the costs of conducting this study.

Funding: This study was supported by Deanship of Scientific Research, Jordan University of Science and technology.

Competing interests: No conflict of

References (41)

  • P. Boesen et al.

    Timing of permanent tooth emergence in two Greenland Eskimo populations

    Community Dent Oral Epidemiol

    (1976)
  • J.S. Friedlaender et al.

    Eruption times of the deciduous and permanent teeth of natives on Bougainville Island, Territory of New Guinea: a study of racial variation

    Hum Biol

    (1969)
  • S.M. Garn et al.

    Advanced tooth emergence in Negro individuals

    J Dent Res

    (1972)
  • E. Koyoumdjisky-Kaye et al.

    Emergence of the permanent dentition: ethnic variability among Israeli children

    Z Morphol Anthropol

    (1981)
  • Lavelle CL

    Study of tooth emergence in British blacks and whites

    J Dent Res

    (1976)
  • R. Leroy et al.

    The effect of fluorides and caries in primary teeth on permanent tooth emergence

    Community Dent Oral Epidemiol

    (2003)
  • P. Adler

    Effect of some environmental factors on sequence of permanent tooth eruption

    J Dent Res

    (1963)
  • R. Leroy et al.

    The emergence of permanent teeth in Flemish children

    Community Dent Oral Epidemiol

    (2003)
  • R. Leroy et al.

    What is the relation between the presence of caries in the deciduous dentition and the chronology of the eruption of the permanent teeth?

    Rev Belge Med Dent

    (2004)
  • J.A. Czecholinski et al.

    Early deciduous tooth loss: the mature or immature eruption of their permanent successors

    Fortschr Kieferorthop

    (1994)
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