According to WHO, 16% to 40% of children aged 6 to 12 suffer a dental trauma.¹This means that almost half of all children are likely to suffer a traumatism involving one or more teeth, during daily activities like playing and sports. In this age group, children have a mixed dentition, with both deciduous and permanent teeth. However, the chronology of permanent teeth eruption places the permanent maxillary central and lateral incisors in the beginning of this time period, around the age of 8.² This fact, corroborated with their placement in the most anterior position, make them the permanent teeth most likely to be affected in a traumatism involving the oral region.

Depending on the direction and the force of the impact, injuries may vary from a small lip swelling or hematoma (caused by its crushing against the central incisor) to fractures of the maxillary bone, especially in severe car accidents.

If a moderate force of impact is applied on the upper frontal teeth, usually one of the following phenomena occurs: either a portion or the entire the dental crown breaks, or the tooth remains intact, but the force is absorbed by its root and transmitted through the dental ligament to the supporting bone. In this case, the tooth suffers a luxation, which can be partial or total, leading to avulsion.

Treatment guides and protocols are available for each scenario, and they are well known by dental specialists. However, basic knowledge and first intention protocols should be made available also for parents, primary school teachers and primary care facilities, who provide the first aid after incidents.

One of the most important information every person should know is the way a fractured tooth fragment or an avulsed tooth should be kept after an accident, and that is on a proper transport medium like saline, saliva or milk. Statistics show that if an avulsed tooth is kept dry no longer than 4 minutes, and it is then transported correctly to a specialized dental office for replantation, that tooth has a 97.9% survival chance after one year, and 73.6% after 10 years. In comparison, if the tooth is kept dry more than one hour, if it is replanted its survival chance after 10 years drops below 30%.³

While dental replantation is an advanced procedure and it is performed in specialized dental practices, a fractured tooth crown, with or without pulp exposure, should be immediately addressed in any dental practice. The most important aspect is the education of parents and primary school teachers, who in cases of accidents where a dental crown was chipped or fractured have to conserve any tooth fragment found. If there is evidence of a dental fracture, but the fragment is not immediately identified, the area should be thoroughly searched in order to try to find the lost fragment. This aspect is very important, since the adhesion between two natural tooth fragments is better than the adhesion between a natural tooth and any other synthetic material available for dental restorations. A dental fragment can be immediately bonded to the fractured tooth, thus completely restoring the aesthetics and function of the tooth quickly, predictably and with a relatively low cost.

In order to emphasize the importance of keeping detached tooth fragments, we present the case of a 9-years-old female patient, who presented to our clinic after a roller-skating accident in the park (Figures 1 and 2).

Figure 1. Extraoral image showing excoriations of the tegument of the nose, philtrum and upper lip.

Figure 2. Impaired mobility of the upper lip due to swelling and pain. However, the fractured left central incisor is clearly visible.

The girl’s mother said she had fallen in the park on a Saturday, and she had the inspiration to pick up and keep the fractured tooth fragment. They went the same day to an emergency dental office, but the general practitioner there said they had no need of the fractured fragment because it cannot be reattached, and that the tooth would require a root canal treatment, a post and a crown. They applied a calcium hydroxide paste on the exposed pulp and a temporary filling, and instructed them to return during the week for continuing the treatment. On Monday they came to our clinic for a second opinion.

Upon inspection the teeth didn’t exhibit abnormal mobility, there was no spontaneous pain and pulp response to cold and electric stimuli was positive. X-ray showed no signs of root fractures or bone resorption (Figure 3), so we decided to try to bond the fractured fragment in the original position.

Figure 3. Periapical X-ray of tooth 2.1

We placed the tooth fragment in saline, since the mother had transported it in a small box with no liquid and it was clearly dehydrated. The tooth fragment remained in saline for the entire duration of the preparation for the bonding procedure. Then we analysed the occlusion, to get a better understanding of the original position of the natural crown (Figure 4).

Figure 4. Analysis of the maximum intercuspidation position. The cervical area of the fractured incisor is clearly oriented more buccally than the right central incisor. Also, the lower left central incisor is tilted to the buccal and to the distal, explaining the buccal orientation of the upper left central incisor.

At this point it became obvious that in the initial situation the crown of the left central incisor was tilted buccally, and this was the reason it was the only tooth which suffered from the impact. Next, we isolated the teeth using rubber dam and we removed the temporary filling material. The pulp chamber presented an opening almost 2 mm wide, and the superficial layer of the pulp was necrotic, probably due to the high alkaline pH of the calcium hydroxide (Figure 5).

Figure 5. Pulp exposure caused by the fracture. Also, this incisal view shows the buccal position of the tooth, compared to the other central incisor (mirror image).

We cleaned the pulp chamber opening with chlorhexidine and we applied MTA (mineral trioxide aggregate) (to be discussed the discoloration effect of MTA and alternative treatments) on the exposed pulp, and we protected the MTA with a light cured cement, to protect it from being inactivated by the phosphoric acid. Then we applied phosphoric acid to the enamel for 20 seconds, and on the dentine for another 15 seconds, and we rinsed it thoroughly with water. We also applied phosphoric acid on the fractured fragment using the same protocol, we gently aspired the excess water with the surgical suction and then we applied two layers of bonding. After light curing the bonding material we applied a thin layer of composite cement used for cementing porcelain veneers (Choice 2, Bisco, USA) and we carefully positioned the fractured fragment.

Immediately after cleaning the excess cement and polishing the restoration, the fractured fragment still had a whiter appearance caused by dehydration, but the overall result was satisfactory (Figures 6 and 7).

Figure 6. Frontal view immediately after restoration.

Figure 7. The natural appearance of the tooth is extremely difficult to mimic using synthetic materials.

Postoperative X-ray showed a good reposition of the tooth fragment, with no visible gaps in the restoration and no apical radiolucency (Figure 8).

We performed vitality testing every month for the following 6 months, with no changes in pulp response. Nine months after the accident, the tooth was still vital, it had a good colour and the restoration had a pleasing natural appearance (Figure 9). The patient was referred to an orthodontist for the initiation of the orthodontic treatment.

Figure 8. Postoperative X-ray. The horizontal fracture line of the crown is barely visible.

Figure 9. Natural aspect of the restoration 9 months after the accident.

Regarding the use of MTA as a direct pulp capping material, recent studies^4,5 have shown that MTA may sometimes cause discoloration of the dental crown. Newly developed materials like Biodentine may presently be a better choice for these procedures, since they do not cause discoloration and have a slightly better success rate.⁴

In conclusion, this case was resolved in a single visit with very reduced costs for the patient and an excellent result, all due to the fact that the mother had the inspiration to keep the fractured fragment.

We consider this information is extremely valuable and it should be known by parents and primary school staff, since unfortunately these incidents happen quite often in this age group.

1. World Health Organization fact sheet: Oral health (April 2012). Available at: http://www.who.int/mediacentre/factsheets/fs318/en/ accessed on 14.08.2017

2. American Dental Association. Tooth eruption – the permanent teeth. Available at: https://www.ada.org/~/media/ADA/Publications/Files/patient_58.ashx Accessed on 14.08.2017

3.IADT Education Committee/Ulf Glendor. Dental Trauma – public health aspects. Available at: https://www.iadt-dentaltrauma.org/images/education%20iadt-ug%202-4%20(%20may%2011th%202015).pdf Accessed on: 14.08.2017

4.Linu S, Lekshmi MS, Varunkumar VS, Sam Joseph VG. Treatment Outcome Following Direct Pulp Capping Using Bioceramic Materials in Mature Permanent Teeth with Carious Exposure: APilotRetrospective Study. J Endod 2017;43:1635-9 [Crossref]

5. Możyńska J, Metlerski M, Lipski M, Nowicka A. Tooth Discoloration Induced by Different Calcium Silicate-based Cements: A Systematic Review ofInVitro Studies. J Endod 2017;43:1593-601 [Crossref]