Correlation between Dental Age and Chronological Age

Coord: Bud Eugen, DMD, PhDAuthors: Todirica Dmitrii Majeri Andrei

U.M.F. TG. MURES FACULTY OF DENTISTRY

Introduction

• What is Age ?

Definition: the length of time during which a being or thing has existed

• How many types of ages do we have?

-Chronological : The length of time a person has been alive

-Dental-Skeletal (Bone Age)-Biological (physiological)-Psychological

IntroductionDetermination of age:In some cases the chronological age is unknown. Trying to

determine the Chronological age using the Physiological age or the Psychological age as an indicator will often lead to erroneous results.

Age determination is used in:-Orthodontics (treatment starting time, preventive measures-eruption of M2 ahead of M1)-Forensic Medicine (cadaver age)-Pediatrics endocrinopathies-Police ( suspect age-minor or adult / customs police)

IntroductionTypes of ages:• Chronological :The length of time a person has been alive.

• Dental - eruption: - temporary teeth - permanent teeth

- mineralization: -calcium salts are deposited into tooth structures such as enamel, dentin and cementum

Dental eruption as an age indicatorFor many decades tooth

eruption was the only criterion available for estimating the chronological age. It was used as an age indicator even in the 19th century:

• In 1836, English law – suspect 7 years of age or younger – could not be accused of crime.

– if proof of age was not available, the medical practitioner was instructed to determine if the first permanent molar had not protruded, there could be no hesitation in affirming the culprit had not passed his 7th year”. (Thomson 1836)

• The Factories Regulation Act of 1833: -no child could be employed before the age

of 9 years. Age was certified by physical appearance and the eruption of the permanent teeth. (Saunders 1837)

Eruption times of permanent teeth

Upper YearsCentral incisor Lateral incisor Canine First premolar Seond premolar First molar Second molar Third molar

7 - 8 yrs8 - 911-1210 – 1110 - 12 6 - 7 12 - 13 17 - 21

Lower YearsCentral incisorLateral incisor Canine First premolar Second premolarFirst molarSecond molar Third molar

6 - 7 7 - 8 9 - 1010 - 12 11 - 12 6 - 7 12 - 13 17 - 21

Dental eruption as an age indicator

• Advantages:-quick procedure-noninvasive-can be done by anyone with minimal knowledge about teeth eruption

• Disadvantages:-considerable discrepancy regarding the eruption seequence-long intervals between eruption of the primary and permanent teeth-can only be used during short periods: -up to 30 months for primary teeth

-from 6 years to 12-13 for permanent teeth

Dental eruption is influenced directly by:- available space- ankylosis - early or delayed extraction of primary teeth - insufficient root development

Dental mineralization as an age indicator

• Other methods for estimating the chronological age, are based on the degree of mineralization of the teeth

• Dental mineralization = the quantity of calcium salts deposited into the enamel, dentin and cement

• Advantages:-accurate and reliable results-have a scientific value

• Disadvantages:-results influenced by many factors -the need for radiographs (patient iradiation)

The OBJECTIVE of this study was to determine if Dental maturity can be used as an reliable indicator for the

chronological age

• Dental maturity:

- is given by the degree of mineralization of the teeth

- determined with the Demirjian Method

Materials and Method Materials – Panoramic radiographs

- 120 radiographs were analyzed from boys and girls within the age group 6-16- -58 OPG from girls- -62 OPG from boys

The patients were part of the romanian and hungarian population.

The radiographs were analyzed by 2 examiners,disagreement between examiners occurred in no more 12% of films and was no more than 1 development stage.

A compass was used to measure the relative length (crown/root).

Materials and Method

Inclusion criteria for the radiographs:-healthy patients, free from health problems-good radiographic quality-the presence of the 7 permanent mandibular left teeth, or if missing the equivalent right mandibular teeth (erupted or not)

Exclusion criteria for the radiographs :-health,endocrine or nutritional disorders-genetic problems-same tooth was missing on both mandibular sides

Materials and Method• The Demirjian Method- Established by Demirjian in 1973- Rates the radiological appearance of the 7 permanentmandibular left teeth- M3 is excluded- In case of a missing tooth, the contralateral equivalent tooth can be used- Necessary spreadsheet data:

1. Illustrations of the development stages of the permanent teeth

2. Written description of each stage

3. Stage score table for each dental development stage

4. Conversion table of the total dental score to a dental age (French-Canadian population as standard)

Method -Demirjian method :

- the development of each of the 7 teeth is divided into 8 stages (A to H)

- the development stage of each tooth must be found out from the radiologic appearance of the tooth on the OPG using illustrations and detailed written criteria

IC – H IL – G C – F PM1 – E PM2 – E M1 – H M2 – D

Method• Demirjian:

-each development stage of each tooth has a particular score

-after the development stage of the 7 mandibular left teeth is established, the score for each stage is added up.

Girl, 8 years, 9 months old

TOOTH STAGE DENTAL STAGE SCORE

IC H 12.9

IL G 12.2

C F 10.3

PM1 E 11.8

PM2 E 12.7

M1 H 16.2

M2 D 11.1

ADDED DENTAL STAGE SCORE 87.2

The added dental score (87.2) must be converted to a Dental Age, using Conversion Tables.

The patient was 8 years and 9 months old, her Dental Age is 9 years.

Results - BoysGroup year Number of

OPG’sAverage ChronologicalAge (CA)

Average Dental age (DA)

Difference in days + ( DA > CA )- ( DA < CA )

5.5 - 6 -> 7 12 6.44 6.6 +58 days

7 – 8 5 7.53 7.6 +26

8 – 9 5 8.41 8.3 -40

9 – 10 4 9.37 9.2 -62

10 – 11 6 10.38 10.2 -66

11 – 12 7 11.53 11.4 -47

12 – 13 6 12.36 12.4 +15

13 – 14 7 13.46 13.6 +51

14 – 15 4 14.62 14.7 +29

15 – 16 6 15.64 15.5 -51

TOTAL 62 10.974 10.95 -87

CA was ahead of DA in the age groups, except 5.5-7 year group when eruption began and 12-15 year group,when growth spurt occurred.DA was behind CA with an average of 87 days.

Results - GirlsGroup year Number of

OPG’sAverage ChronologicalAge (CA)

Average Dental age (DA)

Difference in days + ( DA > CA )- ( DA < CA )

5.5 - 6 -> 7 7 6.4 6.7 +110

7 – 8 5 7.55 7.6 +18

8 – 9 6 8.52 8.6 +29

9 – 10 4 9.61 9.6 -4

10 – 11 5 10.44 10.5 +22

11 – 12 5 11.49 11.6 +40

12 – 13 8 12.55 12.7 +54

13 – 14 7 13.42 13.6 +68

14 – 15 6 14.56 14.7 +51

15 – 16 5 15.6 15.7 +37

TOTAL 58 +42

DA was ahead of CA in all age groups except 9-10 year group.DA was ahead of CA with an average of 42 days.

Results

• The results are directly influenced by:-the precise information given by the patient-the health,nutritional and genetic disorders of the patient-the quality of the radiographs-the subjectivity of the examiners and their experience-the Demirjian standards

– the Demirjian standars include the development criteria (diagrams, written text, scoring system and conversion tables)

– for a more accurate result it is recommended to use the conversion table ( converts the dental score to the dental ag) specifically created for the ethnic population from which the patient is part of

Conclusions• Dental age determination is required in various clinical and scientific disciplines, the

present study assessed the tooth development in the 7 permanent mandibular left teeth,belonging to healthy children aged 6-16, and found that dental age can be used to assess the chronological age.

• Using the Demirjian method, although there was an average overestimation of age in girls of +42 days and an average underestimation of age in boys of -87 days, a significant correlation has been found between the chronological age and the dental age.

• Using the Demirjian standards (conversion table) of another ethnic group, French – Canadian, will also lead to a reliable age estimation when applied to Romanian and Hungarian patients, aged 6-16.

• The use of this method is restricted by the inability to handle missing teeth (the same tooth from both sides of the mandible) or third permanent molars. Over-estimation and under-estimation of age is common when using foreign conversion tables, a fact which can limit the use of this technique if very accurate results are desired.

Bibliography• Dental Maturity- a biologic indicator of chronological age: Digital radiographic study to assess Dental age in

Romanian children - Ana Emilia Ogodescu, Alexandru Ogodescu, Kinga Szabo, Anca Tudor, Elisabeta Bratu • • Estimation of dental age and its comparison with chronological age: accuracy of two radiographic methods -

Shekhar Grover, Charu Mohan Marya, J Avinash and Nidhi Pruthi

• Dental Age Assessment – Developing Standards for UK Subjects. Thesis - Susan Parekh

• Correlation of Radiographic and Chronological Age in Human by using Demirjian’s Method: A Radiographic Study

• Dental Maturity as an indicator of chronological age : Radiographic evaluation of Dental age in 6 to 13 years children of Belgaum using Demirjian Methods.

• Dental age in Dutch children - I. H. Leurs*, E. Wattel**, I. H. A. Aartman***, E. Etty* and B. Prahl-Andersen****

• http://www.sciencedirect.com/science/article/pii/S0379073809005520

• http://link.springer.com/chapter/10.1007%2F978-3-642-28994-1_3#page-1

• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2948737/