Age Estimation Using Secondary Dentin

Age Estimation Using Secondary DentinManjiri JoshiNeethu CParul Khare

OUTLINE titleOverviewWhat is secondary dentin?How is secondary dentin formation and age correlatedWhy is it important in age estimation?Quoting studies on age estimation using secondary dentin classified as - Destructive TechniqueIn-destructive TechniqueMANJARI JOSHI

OVERVIEWtitle

What is Secondary Dentin?

With the eruption of the teeth, and especially with occlusal contact, the pulp begins to receive the slight aggressive effects of normal biologic function (mastication, light thermal changes, chemical irritants, and slight traumas).It is less permeable and also has less dentinal tubules. It is somewhat darker in color than the primary dentine, and its tubules are more curved, sometimes angulated, less regular, and smaller in diameter.

How is Secondary Dentin and age correlated?With aging the pulp cavity gradually becomes smaller because of continuous secondary dentin deposition. As a consequence of this deposition there is a tendency toward eventual pulp obliteration.The pattern for the secondary dentin deposition varies among the different groups of teeth. In maxillary anterior teeth the greatest dentin deposition occurs on the palatal wall of the pulp chamber with subsequent deposition in the incisal tip and remaining walls of the pulp chamber. In molars the greatest dentin deposition is on the floor of the pulp chamber; lesser amounts are deposited on the occlusal (biting) and lateral walls. In advanced age the secondary denti becomes irregular and a gradual increasing loss of dentinal tubules occursDonald R. Morse, Age-related complex systemic changes of the dental pulp and their relationship to aging. ORAL SURG ORAL MED ORAL PATHOL December 1991. Volume 72 Number 6. 721-7455

SIDNEY BENZER. THE DEVELOPMENT AND MORPHOLOGY OF PHYSIOLOGICAL SECONDARY DENTIN. J. D. Res. October1948. VolIuine 27Number 5. 640-646142 total teeth Benzer S- JDR 194820 ue-MRT18 ue SRT51 e-MRT49 e-SRT3 or-SRT1 ovarian cyst1. Physiological secondary dentin is a definite topographical layer of dentinwhich is deposited circumpulpally and follows a definite growth pattern.2. Physiological secondary dentin is a tissue which is present whether thetooth is functional or nonfunctional, oral or extraoral, and should thus be differentiatedfrom primary dentin and adventitious secondary dentin. There isno evidence that this tissue is dependent in its formation on functional stimuli.3. There are several morphological varieties of physiological secondarydentin, ranging from a dense regular dentin to a clear irregular dentin.4. Deciduous teeth appear to have a development and morphology of thephysiological secondary dentin similar to that of permanent teeth.6(1) The study of the chronological development ofphysiological secondary dentin; (2) observations concerning the morphologyof physiological secondary dentin; (3) the correlation between the functionand appearance of the "functional" secondary dentin; and (4) the differentiationbetween physiological secondary dentin, primary dentin, and adventitioussecondary dentin.

GEORGE G. PHILIPPAS Influence of Occlusal Wear and Age on Formation of Dentin and Size of Pulp ChamberVrol. 40, No. 6J. D. Res. November-December 19617

There appeared to be no significant changein the dentin at the roof of the pulp chamber with increasing age over the entire spansof age and occlusal wear studied. (2) The dentin at the floor of the pulp chambershowed a definite increase in thickness with increasing age, this being chiefly responsiblefor the reduction in size of the pulp chamber occlusogingivally. (3) The mesialand distal walls of dentin increased in thickness with increasing age, causing the reductionin size of the pulp chamber mesiodistally. (4) Both the height and the widthof the pulp chamber showed a definite decrease with advancing age, regardless of thedegree of occlusal wear studied.It thus appears that, regardless of occlusal wear up to degree V, dentin formationgoes on uninterruptedly throughout the life of the sound tooth, faster in the earlyyears but more slowly later on. It is this continuous formation of dentin with age thatis responsible for the decrease in size of the pulp chamber.8The symbols adopted range from 1 to 10. Thus (1) signifies age, (2) occlusal wear,(3) thickness of dentin at the roof of the pulp chamber, (4) height of the pulpchamber, (5) thickness of dentin at the floor of the pulp chamber, (6) over-all distancefrom the dentino-enamel junction to the bifurcation of the roots, (7) thicknessof the mesial wall of dentin, (8) width of the pulp chamber, (9) thickness of thedistal wall of dentin, and (10) over-all mesiodistal diameter of the tooth at the cervix.Thus in our text and tables, correlations are denoted (for example) as follows: r13stands for total correlation (Table 6) between age and thickness of dentin at the roofof the pulp chamber. Similarly, r14.2 stands for partial correlation (Table 7) betweenage and height of pulp chamber, with occlusal wear held constant.

A newly erupted upper central incisor (Fig. 1), as seen in age group 6 to 10 years, showed incomplete formation of the primary dentin and no secondary dentinJ. dent. Res. May-June 19669

G. E. MOORE200 central incisors250 microns ( 3 cuts at CEJ and Mid root region)Diameter of Pulp/Diameter of Tooth0.333 young teeth, 0.125 adult teethThe correlation coefficient between age and pulpal size was -0.6210

U. Zilberman, P. Smith (Adv Dent Res 15:42-45, August, 2001)Bitewing radiographs of caries-free teeth without restorations from 247 girls and 271 boys, aged 4 to 16 yearsExact age was known for 160 of the boys and 153 girls.The study was carried out on bitewing radiographs of lower first permanent molars.All measurements were expressed as a ratio of mesio-distal crown width (CW), to minimize the effects of external tooth size and possible errors due to magnification.11CLASSIFICATION DESTRUCTIVE METHODS Sectioning of teeth is necessary. Hence can be used only in dead individuals.

NON DESTRUCTIVE METHODSAge estimation using radiography (opg, CT, CBCT etc)Can be used in dead as well as living individuals. NEETU. C DESTRUCTIVE METHODSMost important :gustafsons methodAll other studies are variations focusing on use of one or more of the modified criteria.13GUSTAFSONS METHODSample size - 41 TEETH6 PARAMETERS ATTRITION SECONDARY DENTIN FORMATION PERIODONTITIS CEMENTUM APPOSITION ROOT RESORPTION TRANSPARANCY OF ROOT 4 POINT SYSTEM

ATTRITIONSECONDARY DENTIN FORMATIONPERIODONTITISCEMENTUM APPOSITIONROOT RESORPTIONTRANSPARANCY OF ROOT14FORMULA Y= 11.43+4.56X Y=AGE X=(A+S+P+C+R+T)

Standard deviation +- 3.6yearsHow ever later studies were unable to reproduce the same level of accuracy.Accepted standard deviation +- 10 to 15years

relation between point value and age for 41 teeth was calculated using the graph and found that there was anincrease in points corresponding to an increase inage, and that it was possible to draw a regression line for the relation betweenage and points.15DALITZ (1962)Re evaluation of Gustafsons method146 anterior teeth was examined root resorption and secondary cementum formation disregarded.5 point system.

S'o No secondary dentine.S'l Secondary dentine has just begun to form at the incisal or occlusal end of the pulpchamber.StZ Secondary dentine fills one third of the pulp chamber.Sf3 Secondary dentine fills two thirds of the pulp chamber.Sg4 Secondary dentine fills the whole of the pulp chamber.16FORMULA E' = 5.1464' + 5.338P ' + 1.866s' + 8.411T ' + 8.691Standard deviation +- 6years ( when 4 anterior teeth used) +- 8.1 years( when single tooth is used)MAPLES (1978)Sample size: 335 teethTOOTH POSITION as a factor along with the 6 Gustafsons parametersMultiple regression was carried out by regressing each of the variables against age.

( instead of adding them together

18

Second molar gives the best results (tooth position 7)Standard deviation +- 5.00years of formula APSCT position 7 is the smallest standard deviation for age estimation in adults.ST over all weighted formula gives best results for all teeth and requires only secondary dentin and root transparency.

This means teeth with broken crowns or no evidence of periodontal attachment and lost cementum still yields accurate age estimatesIt can also be used on all populations, no matter the differences in the dietary practices.20SOLHEIM(1992)Sample size 800 teeth(80 per tooth type)selected measurements of different dental parameters most related to age, as found in various studies to present a new method for dental age estimation based on multiple regression analysis for each type of tooth.

Inclusion of the factors of sex and colour depends upon the condition ofthe body and teeth. sex may be difficult todetermine, and the tooth colour may have changed after death. 22ARTICLESJohanson (1971)Metzger (1980)Lamendin et al (1992)Kiesal (1973)Drusini (1993)Ito(1972,1975)Wei et al(1983)Lopez Nicolas et al (1990)

non destructive techniquesPARUL KHARELIVING DEAD / EXTRACTED TEETH- INTACTNON DESTRUCTIVE TECHINIQUES- INTACT TEETH Kvall: Periapical- 1995Kristin M. Kolltveit, Tore Solheim Kvall -1998Bosmans: CT- 2005Yang Willems: CBCT - 2006Hazha, Thevissen: CBCT - 2009Cameriere Lower premolars, OPG - 2012 Cameriere CI LI, periapical - 2013 Vandevoort: Microfocus X-ray computed tomography -2004Drusini: OPG- 2008H. Aboshi: Microfocus X-ray computed tomography - 2010Jagannathan CBCT-2011

Age- 20-87 years Sex - bothSample size 100/Caucasian whites Radiograph type periapical radiographs :Parallelling technique for standard RX Teeth 6 Maxillary Central and Lateral Incisors & Second PremolarsMandibular Lateral Incisors, Canines and First Premolars.

Kvall: age estimation of adults from dental radiographs 1995 26

Length and Width Ratios

Pulp Root Length (P) Pulp Tooth Length (R) Tooth Root Length (T) Pulp Root Width at CEJ (A) Pulp Root Width at Mid Root Level (C) Pulp Root Width at Mid Point b/w Level C & A (B)

Kvall: age estimation of adults from dental radiographs 1995 27

Aim: relationship between the size of the pulp and the toothAge: 20 to 87 years, and a mean age of 46Sample size: 40 patientsNumber of teeth: six teeth in each patientRadiographs: periapical radiographs Manual measurements: vernier callipers and a stereomicroscope with a measuring eyepiece. Computer assisted measurements: image analysis software. Statistical analyses: Statistically significant intra- and inter-observer differences between the manual and computer-assisted measurements. The results implied that, despite advanced technology, conventional methods may be better suited for measuring linear morphological parameters in dental tissue.

Kristin M. Kolltveit*, Tore Solheim, Sigrid I. Kvaal. Methods of measuring morphological parameters in dental radiographs Comparison between image analysis and manual measurements. Forensic Science International 94 (1998) 8795. Kristin , Solheim & Kvall-image analysis and manual measurements. 199828

Aim: evaluate whether this approach feasible & adequate repeatability when applied on panoramic radiographs. Age: 19 to 75 yearsSample Size: 197 Radiographs : panoramic radiographs Teeth: 6 teeth Result: There appears to be no significant difference between applying the original technique on standard long-cone periapical radiographs or on orthopantomograms, especially when carrying out measurements on all six selected teeth.Recommended - panoramic radiographs, may lead to age estimations that are comparable to those based on the original technique. if at least the selection criteria are respected and good quality orthopantomographs with clear radiological image are used.

Nathalie Bosmansa, Peirs Annb, Medhat Alya, Guy Willems. The application of Kvaals dental age calculation technique on panoramic dental radiographs. Forensic Science International 153 (2005) 208212 BOSMANSA 200529

Aim: to test the reliability and applicability of the method developed by Kvaal et al.Age range: females 2073 years (mean 36.73); males it is 2062 years (mean 35.26).Sex : 143 female and 136 male /Australian individuals Sample size: 279 radiographsTeeth: 6 teeth Radiographs: digital orthopantomograms (OPG)Results- most accurate model maxillary central incisor (SEE _9.367 years), maxillary second premolar (SEE _9.525 years). Regression models based on the measurement of multiple teeth improved age prediction accuracy (SEE _7.963 years). This method, therefore, offers a statistically quantified methodological approach for forensic age estimation in Western Australian adults.

Shalmira Karkhanis *, Peter Mack, Daniel Franklin Age estimation standards for a Western Australian population using the dental age estimation technique developed by Kvaal et al. Forensic Science International 235 (2014) 104.e1104.e6Studies based on KVALL: Australia 201430

Aim: Radiographs can be used to indirectly measure the rate of secondary dentine deposition which is depicted by reduction in the pulp areaAge: 18-72Sample size: 200 Teeth 6 All theRadiographs: Panoramic radiographs Results: It was observed that 2 variables AR and bcontributed significantly to the fit and were included in the regression model, yielding the formula: Age = 87.305480.455(AR)+48.108(b). Statistical analysis indicated that the regression equation with selected variables explained 96% of total variance with the median of the residuals of 0.1614 years and standard error of estimate of 3.0186 years.Conclusion: There is significant correlation between age and morphological variables AR and b and the derived population specific regression equation can be potentially used for estimation of chronological age of individuals of Karnataka origin.

Manjushree Juneja, Yashoda B. K. Devi1, N. Rakesh1, Saurabh Juneja2 Age estimation using pulp/tooth area ratio in maxillary caninesA digital image analysis. Journal of Forensic Dental Sciences / September-December 2014 / Vol 6 / Issue 3Studies based on KVALL: India 2014 U. Zilberman, P. Smith (Adv Dent Res 15:42-45, August, 2001)Bitewing radiographs of caries-free teeth without restorations from 247 girls and 271 boys, aged 4 to 16 yearsExact age was known for 160 of the boys and 153 girls.The study was carried out on bitewing radiographs of lower first permanent molars.All measurements were expressed as a ratio of mesio-distal crown width (CW), to minimize the effects of external tooth size and possible errors due to magnification.31

Aim: attempt establishing a correlation between the chronological age of a certain individual and the pulp/tooth volume ratio of one of the teeth. Number of samples- 19 different individuals2 28 single rooted teeth

Age: 23 to 70 years of Teeth: 15 incisors, 12 canines, 1 premolarProcedure of exposure - CBCT(skin dose 1.19 mSv, total dose 20 microSv per examination).A custom-made voxel counting software for calculating the ratio between pulp canal versus tooth volume based on cone-beam CT tooth images was developed and evaluated. Results: showed a moderate correlation between the pulp/tooth volume ratio and biological age with a coefficient of determination (R2) of 0.29. Recommended: that the developed technique showed promising results for dental age estimation in a non-invasive manner using cone-beam CT images in living individuals.Fan Yang a,b, Reinhilde Jacobs a, Guy Willems. Dental age estimation through volume matching of teeth imaged by cone-beam CT. Forensic Science International 159S (2006) S78S83YANG, JACOBS & WILLEMS - 200632

Procedure

Clinic scanning

Image reconstruction

Pre-processing (drawing the boundary manually)

Post-measurement

Took less than 1 h per patient.

Fan Yang a,b, Reinhilde Jacobs a, Guy Willems. Dental age estimation through volume matching of teeth imaged by cone-beam CT. Forensic Science International 159S (2006) S78S8333

An original cone-beam CT image slice: which was exported as tiff 8 bits image format by the dedicated software iDixel after adjusting the window/ level and reslicing.Based on the fact that the periodontal ligament space was not clear inmost of the images, a manual pre-processing step was operated before segmentation.After image magnification in paint of Microsoft Windows1 (Microsoft, Seattle, USA), the black curves were drawn along the contour of the tooth in certain blurry areas.

(a) The transparent view was used to adjust the threshold of segmentation. The observers can set different parameters to change the segmented area. (b) Theprogram labeled different segmented regions, the figure shows the regions marked by different colors. (c) The figure shows the final segmentation result.34

Aim: dental age estimation based on the ratio between the volume of the pulp and the volume of its corresponding tooth, calculated on clinically taken cone beam computed tomography (CBCT) Age: 10 and 65 yearsSex: 57 female and 54 male patients Sample size: 111 CBCT images (Scanora_3D dental cone beam unit) Teeth: 64 incisors, 32 canines, and 15 premolarsStatistical analysis: A linear regression model was fit with age as dependent variable and ratio as predictor, allowing for interactions of specific gender or tooth type. Result: The strongest Pearson correlation coefficient between the pulptooth volume ratio and age was measured on incisors.

Hazha Star,1 D.D.S.; Patrick Thevissen,1 M.Sc.; Reinhilde Jacobs,2 Ph.D.; Steffen Fieuws,3 Ph.D.;Tore Solheim,4 Ph.D.; and Guy Willems,1 Ph.D. Human Dental Age Estimation by Calculation of PulpTooth Volume Ratios Yielded on Clinically Acquired Cone Beam Computed Tomography Images of Monoradicular Teeth. J Forensic Sci, January 2011, Vol. 56, No. S1HAZHA STAR & PATRICK THEVISSEN: 2011This was expected because all the correlation coefficients between the variable ratios related to secondary dentine formation and age used in the Kvaal et al. study, equally, provided the highest correlation outcomes in the incisor group. 35

Different separation and segmentation steps of an upper central incisor on CBCT DICOM data imported in Simplant_ Pro software. To segment the selected tooth, a mask is created and an optimal separating grayscale threshold is chosen on axial images showing the tooth root in bone. The mask is cropped in three axes to limit it to the closest region of the chosen tooth, and a 3D image is calculated (a). On this 3D calculation, regions not belonging to the tooth are selected and roughly removed. Next slice by slice in each reproduction orientation manual erases and correcting draws are performed to remove the cortical bone parts at root level and parts of the neighboring teeth at crown level. This separation cannot be established by adapting the threshold because there is a too small or no gray value difference between the involved structures. A 3D calculation of the mask assembling all adapted slices generates an image on which the program can calculate the tooth volume (b). At the inner side of the calculated image, a free space is available corresponding with the pulp chamber (c). After adapting the segmentation by drawing a stop in the most apical axial slice of the tooth, a new mask is created filling the internal tooth hole. A 3D calculation of the pulp chamber mask allows for a calculation of the pulp volume (d).

36

Aim: of this paper is to examine the relationship between age and age-related changes in the pulp/tooth area ratio in monoradicular teeth, with the exception of canines,Sex: 289 women and 317 menAge: 18 and 75 yearsSample size: 606 orthopantomograms / Spanish white Caucasian patientsRadiographs- orthopantomography (OPG)

Regression analysis of age of monoradicular teeth indicated that the lower premolars were the most closely correlated with age. Multiple regression analysis, with age as dependent variable and pulp/tooth area ratio as predictor, yielded several formulae. R2 ranged from 0.69 to 0.75 for a single lower premolar tooth 0.79 to 0.86 for multiple lower premolar teeth.

Roberto Cameriere a, Stefano De Luca b,*, Inmaculada Aleman b, Luigi Ferrante c, Mariano Cingolani. Age estimation by pulp/tooth ratio in lower premolars by orthopantomography. Forensic Science International 214 (2012) 105112 CAMERIERE: PM -2012Since 2004, in order to examine patterns of secondary dentine apposition, Cameriere et al. [16] have been extensively studying the pulp/tooth area ratio of the canines by panoramic and peri-apical X-ray images.

Cameriere et al. [20], the X-ray images were photo edited using AdobePhotoshop [5]. Twenty points from each tooth outline and 10 for each pulp outlinewere identified and used to evaluate both tooth and pulp areas.37

Depending on the available number of premolar teeth, the mean of the absolute values of residual standard error, at 95% confidence interval, ranged between 4.34 and 6.02 years, showing that the pulp/tooth area ratio is a useful variable for assessing age with reasonable accuracy.

Aim: to examine the application of pulp/tooth area ratio as an indicator of age in upper and lower incisors, both lateral and medial.Sex: 62 men and 54 womenAge: 18 and 74 yearsRadiographs: peri-apical X-raySample size: 116 individualsStatistical analysis: The total variance explained by the regression equation ranged from 51.3% of age, when lower lateral incisors were used as explanatory variable, to 81.6% when upper lateral incisors were used. The accuracy of the corresponding regression model yielded ME 8.44 and 5.34 years, respectively. Result: These results show that, although incisors are less reliable than canines or lower premolars, they can be used to estimate age-at-death when the latter are absent.Age estimation by pulp/tooth ratio in lateral and central incisors by peri-apical X-ray. R. Cameriere. Cunha, S.N. Wasterlain, S. De Luca,E. Sassaroli, F. Pagliara, E. Nuzzolese, M.Cingolani, L. Ferrante. Journal of Forensic and Legal Medicine 20 (2013) 530e536 CAMERIERE: CI & LI -2013

U. Zilberman, P. Smith (Adv Dent Res 15:42-45, August, 2001)Bitewing radiographs of caries-free teeth without restorations from 247 girls and 271 boys, aged 4 to 16 yearsExact age was known for 160 of the boys and 153 girls.The study was carried out on bitewing radiographs of lower first permanent molars.All measurements were expressed as a ratio of mesio-distal crown width (CW), to minimize the effects of external tooth size and possible errors due to magnification.39

Aim: Age estimation by pulp to tooth area ratio in canines Sex: 114 males and 114 femalesAge: 16-72 years Sample size: 228 teethTeeth: 456 canines (upper, lower and both) in an Indian sample) Exposure: radiovisiography techniqueResult: Linear regression equations were derived for upper canine, lower canine and both using the AR to estimate chronological age.The efficacy of these equations was also evaluated in younger age group (