## 5 Discussion
### Recommendations  
1. When unidentified remains are found in large-scale disasters or during individual incidents, the identification of human remains is usually performed [8]. If the remains are not identified from belongings, facial configuration, etc., identification by dental, fingerprint, and DNA analyses is also required [1; 2; 3; 4; 9]. Using dental analysis for the identification of remains is an extremely valid method for the following reasons: (a) a high incidence of comorbid dental diseases and a large number of patients visiting dental offices, (b) a long history of dental treatment, (c) a variety of dental treatments, (d) a high frequency of use of X-ray imaging during dental treatment, and (e) the hardness of teeth results in minimal deterioration even with advanced postmortem changes or catastrophic injuries [10; 11; 12; 13; 14].  
2. The collection of dental findings began 8.5 h after this particular incident. Previous experiences have shown that constant preparation is necessary for emergencies wherein developing a list of reference articles, preparing belongings in advance, and establishing contact lines are essential.  
3. Preparing access to dental instruments and equipment, including dental mirrors, dental tweezers, probes, toothpushes, floss, mouth opening instruments, lights (i.e., pen- or head-type), black lights, writing equipment (antemortem dental charts, post-mortem dental charts, collation paper, ballpoint pens, pencils, erasers, and magic pens), intraoral camera, mouth hook, photographic mirror, ruler, X-ray equipment set, X-ray protective apron, paper towels, hand sanitizer, tissue paper, and recording media.  
4. With regards to equipment, easy-to-remove clothes, disposable caps, headlights, masks, gloves, boots or thick-sold washable shoes, goggles, face shields, and disposable gowns are required.  
5. Training dentists to collect dental findings is crucial [15]. Three dentists and co-medicals can assemble a team and assign different roles for collecting the dental findings. Effective operations require preparation for testing procedures, reading of dental findings, and sufficient lighting. At 11:00 pm on the day of the incident, performing the autopsies and examinations took considerable time, particularly because collecting dental findings was difficult and required some examinations to be postponed to the next day.  
This report also supports the need for more accurate dental identification after large-scale fires. However, considerations in the comparison with other large-scale fires are necessary. First, the bodies in this incident included deaths due to crime; therefore, conducting forensic autopsies and collecting dental findings from all bodies was desirable. If possible, this is the optimal method to simultaneously collect dental findings and perform autopsies because visual fields are sufficiently maintained. Second, fires in urban areas are controlled relatively quickly whereas natural fires require more time. Therefore, differences in tooth carbonization, omission, and deformation should be considered. Finally, this particular incident occurred in an office building. In residential areas and farming communities, differentiating human remains from those of pets and livestock may also be necessary. In the Black Saturday bushfires in Australia, identification was considerably delayed because of the mixture of teeth and bones in deformed human and animal remains [16]. Further surveys and analyses are needed to determine methods for more accurate and prompt identification after large-scale fires.