Cranial Suture Closure and Age Determination in the Thai Population

Abstract

Objective: To determine whether the time of cranial suture closure in the Thai population has changed compared to findings in the past or not. Is there any difference between sexes? Also to determine the difference between the time of ectocranium and endocranium closure and their reliability for age determination in the Thai population.

Methods: The time of closure of the sagittal, coronal and lambdoid sutures was studied in 166 crania (known age Thai adults, 30 females and 136 males) for which the medicolegal autopsies were performed at the Department of Forensic Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, during the year 2006, age range between 15 to 83 years old. The sagittal suture was divided into four segments and those of each side of the coronal and lambdoid sutures into three segments. The degree of suture closure was recorded for endocranial and ectocranial sides by our scoring system. The sum of all endocranial suture scores, which were also defined as çComposite scoresé, were divided into 7 stages (designated as S0-S6). The graph showing the association between chronological age and endocranial composite scores was plotted. The correlation coefficient, chi-square tests, and independent t test were used for statistical analysis, P-value <0.05 was statistically significant.

Results: It was found that the Thai new generationûs ectocranial suture closure starts and completes earlier than those in the past while endocranial sagittal suture closure starts and completes at a similar time as found in the past. Endocranial sutures start closing before ectocranial and endocranial closure is more related to age than another and no difference between sexes could be found. Using the closure of each suture separately to determine the age at death, somehow, may not be appropriate while using the sum of suture scores reduces variations. The sum of endocranial suture scores (composite scores) are statistically proven to be most related to age without significant statistical difference between the two sexes. The association between age and the interval of composite scores was shown and suggested to be the age predicting tool.

Conclusion: The time of cranial suture closure is stated as one of indicators of age at death but its progression varies greatly According to our study, using composite scores helps in diminishing this variation. The information on suture closure is useful when other criteria are not available or when being used in conjunction with other attributes.