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An Official Publication of the Indian Association of Oral and Maxillofacial Pathologists

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Year : 2021  |  Volume : 25  |  Issue : 3  |  Page : 515-516

Tooth eruption clock: A novel learning aid

1 Department of Oral Pathology, Faculty of Dentistry, Meenakshi Ammal Dental College, Meenakshi Academy of Higher Education and Research, Chennai, Tamil Nadu, India
2 GRM Dental Clinic, Chennai, Tamil Nadu, India

Date of Submission06-Sep-2021
Date of Acceptance19-Oct-2021
Date of Web Publication11-Jan-2022

Correspondence Address:
Manoj Prabhakar
Department of Oral Pathology, Faculty of Dentistry, Meenakshi Ammal Dental College, Meenakshi Academy of Higher Education and Research, Chennai, Tamil Nadu
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jomfp.jomfp_318_21

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Chronology of tooth eruption is the most preliminary and crucial topic which is covered in the undergraduate syllabus of the dental curriculum. Eruption of permanent and primary teeth follows a particular time sequence. Both maxillary and mandibular arch has similar number of teeth, beginning from central incisors to molars. The pattern of eruption differs slightly between maxillary and mandibular arch. Remembering the years or months in a numerical manner is the usual way by which a student learns the eruption chronology. Eruption clock is a specially designed learning aid, which makes this teaching–learning process a lot easier, effective and practical.

Keywords: Chronology, eruption clock, eruption sequence, eruption time, permanent teeth

How to cite this article:
Prabhakar M, Sivapathasundharam B. Tooth eruption clock: A novel learning aid. J Oral Maxillofac Pathol 2021;25:515-6

How to cite this URL:
Prabhakar M, Sivapathasundharam B. Tooth eruption clock: A novel learning aid. J Oral Maxillofac Pathol [serial online] 2021 [cited 2022 Jan 17];25:515-6. Available from: https://www.jomfp.in/text.asp?2021/25/3/515/335527

   Introduction Top

Chronology of eruption is the sequence by which the tooth erupts into the oral cavity. Eruption sequence for teeth is often studied by the dental formulae and tables representing the eruption period.[1],[2] This traditional method of learning is being followed in the curriculum for years and no simplified version has evolved till now to break the barrier set in the minds of students. However, there are few studies in the literature, which mention about the variation in eruption chronology among different population, but there seems to be a lacunae in application of this knowledge practically.[3],[4],[5],[6] Moreover, queries related to eruption period of teeth has now become a curious issue among parents who visits the dentist regarding their child's oral health status. Questions like 'When does the first tooth erupt?' and “Which tooth is permanent?” are commonly encountered in a clinical setup.[7] Dentists are in a position to address these queries raised by the parents and to make them understand the sequence of eruption in a way, which they can easily accept and implement. To overcome these hurdles, an uncomplicated and an efficacious tool is required, which benefits the academic, clinical and common audience.

Tooth Eruption Clock is especially designed for effective learning of chronology of permanent teeth eruption in a visual, easier, effective and a convenient way. The conventional method of learning of chronology of permanent teeth eruption is by simply memorizing the years or months in numbers, as given in the textbooks. The often-followed method of teaching chronology of tooth eruption is by preparing a table or chart with figures and names of all teeth along with their corresponding eruption period. This existing method makes the learning a cumbersome process, creating resentment and reluctance toward the subject. The monotonous method of memorizing the numbers with the help of tables and charts is not retained in the minds of students for a long time. Therefore, an attempt is made to develop a novel tool for effective learning of chronology of permanent teeth eruption in a simplified and practical way that will be retained in the minds of the students.

   Description Top

The tooth eruption clock comprises an analog type wall clock with hands to indicate hour and minute. It comprises numbering from 6 to 17 with the numbers positioned exactly in the same place of 1–12 of a normal clock and adapted to represent the year of eruption of permanent teeth. The images of permanent tooth along with its name are positioned between the numbers corresponding to eruption period of the permanent tooth. For example, maxillary central incisor erupts at the age of 7–8 years, and the respective image is included in between the numbers 7 and 8 in the eruption clock. The name of each tooth is mentioned adjacent to every tooth image (e.g., CI – central incisor, PM – Premolar). Both the maxillary and mandibular teeth are differentiated with a bar line in which maxillary teeth is positioned above the bar line and mandibular teeth is positioned below the bar line. A combination of both maxillary and mandibular teeth are represented in a few places on the clock, based on their chronology of eruption [Figure 1].
Figure 1: Tooth eruption clock representing chronology of eruption

Click here to view

   Significance and Merits Top

This learning aid carries the novelty of portraying the images of the tooth in a uniquely designed clock, which represents the numbers located in the same position as it is in the normal clock. Tooth eruption clock will be an effectual and potential learning tool for the students to overcome the traditional learning method of memorizing the eruption period. It simplifies the conventional method of learning the eruption sequence to a visual method, by looking at the specially designed tool, time and again. It serves both the faculties and students in mutual learning and understanding of the subject, thereby resulting in higher knowledge retention. Moreover, this tool can even be beneficial for parents who consults the dentist regarding their child's tooth eruption status. This particular type of eruption clock can be showcased in lecture halls, tooth morphology laboratories, dental museum, dental clinics, paediatric departments and even at homes, thereby promoting oral health education not only to the students undergoing graduation but also to the public.

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Conflicts of interest

There are no conflicts of interest.

   References Top

Nelson SJ. Development and eruption of the teeth. In: Wheeler's Dental Anatomy, Physiology and Occlusion. 1st South Asia ed. India: Reed Elsevier India Pvt. Ltd.; 2015. p. 30-1.  Back to cited text no. 1
Berkovitz BK, Holland GR, Moxham BJ. Dento-osseous structures. In: Oral Anatomy, Histology and Embryology. 4th ed. china: Elsevier; 2009. p. 12-3.  Back to cited text no. 2
Kochhar R, Richardson A. The chronology and sequence of eruption of human permanent teeth in Northern Ireland. Int J Paediatr Dent 1998;8:243-52.  Back to cited text no. 3
Hernández M, Espasa E, Boj JR. Eruption chronology of the permanent dentition in Spanish children. J Clin Pediatr Dent 2008;32:347-50.  Back to cited text no. 4
Chaitanya P, Reddy JS, Suhasini K, Chandrika IH, Praveen D. Time and eruption sequence of permanent teeth in Hyderabad children: A descriptive cross-sectional study. Int J Clin Pediatr Dent 2018;11:330-7.  Back to cited text no. 5
Lakshmappa A, Guledgud MV, Patil K. Eruption times and patterns of permanent teeth in school children of India. Indian J Dent Res 2011;22:755-63.  Back to cited text no. 6
  [Full text]  
Rathore K, Tandon S, Sharma M, Kalia G. Queries of parents related to their children's oral health in rural and urban area of Jaipur: A clinical study. Int J Clin Pediatr Dent 2019;12:88-91.  Back to cited text no. 7


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