# 2D vs. 3D Radiological Methods for Dental Age Determination around 18 Years: A Systematic Review
## 3 Results
Suspension levels, i.e., when the margin of deviation from the standard is substantial and equipment are no longer fit to use, were available for image noise, image density values, computed tomography dose index (CTDI) free in air, radiation field size, radiation output repeatability and reproducibility, operating potential, and Dose-Area-Product (DAP). Due to the limited information available, at that time, from large-scale audits of equipment in clinical use, and taking into account the continuing developments in equipment, they took a pragmatic approach and concluded that suspension levels for dental CBCT should be continuously kept under review in the light of growing experience of testing equipment in practice. Furthermore, they pointed out the importance of periodical revision of acceptability criteria for dental CBCT also because of its usual location in primary care facilities, where quality assurance and maintenance of equipment may not be optimal. Recently, [PERSON] and [PERSON] [42] discussed the patient's risk in dental radiography presenting their experience in dose optimization when exposing dental patients to intraoral, panoramic, and CBCT X-rays. They concluded that if a proper optimization of the instruments' settings and of the patient's positioning are made, it is possible to stay in a reasonable range of radiological exposure ensuring at the same time a good resolution of the acquired images. Focusing on forensic medicine, it is possible to notice that since 10 years ago, CBCT was used with different purposes, such as, for example, in forensic identification through facial soft tissues thickness measurement and craniofacial reconstruction, and frontal sinus, mandibular lingual canals or teeth superimposition; for bite marks analysis; for sex determination identifying a possible dimorphism of the mandibular body, the foramen magnum, and the maxillary of frontal sinus; and of course for age estimation [43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54]. Age estimation through CBCT images focused on different craniofacial structures: cervical vertebrae shape; spheno-occipital synchondrosis ossification; mandibular condyle cortication; structural changes of teeth and buccal alveolar bone level; pulp-tooth volume ratio; and dental maturation. [PERSON] et al. [55] used cervical vertebrae shape analysis to build bone and forensic age estimation regression models and they found that there was no significant difference between form space and shape space in both age estimation models even if, for gender comparison, this two age estimation models had a higher explanatory power for males. In their study, the narrowest prediction intervals among the multivariate regression models were 19.63 for bone age and 2.99 for forensic age: the latter interval gives an idea of the incertitude of a forensic age estimation elaborated through this method. [PERSON] et al. [56] focused on the analysis of spheno-occipital synchondrosis, and they found that the mean ages for its complete fusion were 18 and 20 years of age for females and males, respectively, with an interobserver agreement ranging between substantial and perfect and an intraobserver substantial agreement. Therefore, they concluded that the spheno-occipital synchondrosis ossification stage evaluation has a value for age estimation around the age of 18 years. [PERSON] et al. [57] investigated the effectiveness of using the condylar cortication as a new method of age estimation, and they found three different stages around \(14.14\pm 2.3\) years, \(16.11\pm 3.18\) years, and \(19.39\pm 3.96\) years for males, approximately one year less for females, that are all important age turning points from a public system perspective. It must be considered they also found that the type of cortication in the right and left condyle might be different for the same individual.