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Three Part Question

In [a child with a traumatic avulsion of a tooth] does [transport of the tooth in milk or some other medium as opposed to being kept dry] improve [survival of the tooth after replantation]?

Clinical Scenario

A healthy 14-year-old boy involved in an altercation with another boy sustains injury to his jaw and two of his incisor teeth are avulsed. He attends the Emergency Department with his teeth wrapped in tissue paper. The nurse at the triage asks whether we need to put the teeth in milk immediately. You wonder whether this is 'Nanny advice' or evidence-based?

Search Strategy

MEDLINE 1950 - March week 1 2009
[(deciduous tooth.mp. or exp Tooth, Deciduous/) OR (exp Milk/ or milk tooth.mp.
exp Tooth/ or tooth.mp. or exp Tooth Avulsion/) OR (teeth.mp.) OR (dent$.mp.)] AND [(reimplant$.mp.) OR (exp Tooth Replantation/ or exp Replantation/ or replantation.mp.
replant$.mp.)] AND [milk.mp. or exp Milk/]

Search Outcome

Medline : 45 papers were found. There were 3 relevant case reports and 3 retrospective cohorts. two further papers were found from the references.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Mackie IC, and Worthington HV 1992 UK	46 replanted avulsed permanent teeth studied in 36 patients from April 1982 to May 1989.	Retrospective study.	Replantation	Successful for 21 teeth (45%), uncertain for 20 teeth (44%), failed for 5 teeth (11%).	Small sample size and unequal follow-up period. Late failures would change the overall results.
			Storage medium	13 successfully replanted teeth (65%) were brought in milk, saliva or saline. Only 7 (35%) were brought in dry (P<0.01).
Nordenvall KJ 1992 Scandinavia	14 yr Swedish boy; Tooth preserved in refrigerated milk for more than 12 hours.	Case study.	Tooth had survived at four years follow up	Successful survival of tooth when stored in standard milk even beyond the recommended time of 30-60 minutes	Case report only.
Kinoshita S et al. Japan 2002	Comparison of outcomes from tooth avulsion at home or at school. 32 avulsed teeth ,but 18 could not be replanted and 4 lost to follow-up, leaving 10 children with 10 traumatic tooth avulsions - five at school and five at home.	Case series.	Wet storage	5 teeth, all survived.	10 case reports only.
			Dry storage	5 teeth: 3 did not survive, 1 survived, 1 uncertain (short follow-up)
Mackie IC, and Worthington H 1993 UK	49 children (6-14 years old) with avulsed permanent incisor teeth. 36 children had 46 teeth replanted.	Retrospective cohort.	Storage medium	Dry 26 (60%), saliva 8 (19%), milk 3 (7%), saline 2 (4%), water 2 (4%), combination 2 (4%).	No data about the relative merits/successes of the wet media. This seems to be based on the same data as their 1992 paper.
de Carvalho Rocha 2008 Brazil	Child aged 30 months with an avulsed incisor.	Case report.	Tooth survival	Successful replantation after storage in milk.	Case report with dental treatment obtained in 30 minutes.
Bhambani SM 1993 USA	9 year old boy with an avulsed incisor.	Case report.	Tooth survival	Despite storage in milk and replantation after about 45 minutes there was evidence of necrotic pulp at 4 weeks.	The tooth was extracted after a year.
Andreasen et al I 1995 Denmark	400 avulsed and replanted permanent teeth. Pulpal revascularisation was considered possible in 94 teeth.	Prospective cohort.	Successful pulpal revascularisation	32 teeth (34%)	Although this was a big study the final numbers are small because of very variable storage conditions (duration of dry time, duration of wet time and combinations of dry and wet time).
			Storage in own saliva	1 success from 5 teeth
			Storage in another's saliva	1 success from 5 teeth
			12 matched pairs stored in saliva v saline	5 successes v 3 successes
			Wet storage	Storage for longer than 5 minutes reduced chance of success
			Dry storage	Linear reduction in chance of success with length of storage time
Andreasen et al. II 1995 Denmark	400 avulsed and replanted permanent teeth.	Prospective cohort	Periodontal ligament healing	96 teeth (24%)	Variable storage conditions (duration of dry period even in wet stored teeth, and duration of wet storage) so that there were very few matched pairs of teeth.
			Wet storage: saline v saliva 9 matched pairs	Successful healing in 3 of each group.
			33 teeth grouped according to saline or saliva storage	4 saline v 6 saliva group showed PDL healing (P=0.73)
			Wet storage time	0-20 min 60% success, >21 min 155 success (Chi square 0.003)

Comment(s)

A viable periodontal ligament (PDL) is important for proper physiologic healing of replanted teeth. One of the critical factors affecting outcome is the way the tooth is handled during the extraoral period. A suitable storage medium should have a physiologic osmolality in order to keep the PDL cells in as healthy a condition as possible. Milk has an osmolality within physiologic limits. In vitro studies suggest that it is superior to saliva (Blomlof and Otteskog 1980) and to Eagle’s medium (Blomlof 1981) and other media (Ashkenazi et al. 1999, Lekic et al. 1998) in terms of PDL cell viability. Milk appears to be the storage medium of choice in an emergency situation, although a new storage medium: Propolis may be better (Martin and Pileggi 2004). It has been reported that the length of time that a tooth spends out of the mouth significantly influences the incidence of root resorption. Andreasen and Hjorting-Hansen found that 90% of teeth replanted within 30 minutes did not develop resorption, while 93% of those replanted after 90 minutes of dry storage did. A statistically significant relationship has been shown between success of treatment and the medium in which the tooth was stored. However, even when teeth were stored dry, some were still treated successfully, showing that dry storage is not an absolute contra-indication to replantation (Mackie and Worthington 1992). Given the importance of rapid storage in an appropriate medium it has been suggested that locations where tooth avulsions are likely to occur should be provided with tooth rescue boxes containing such a medium (Filippi et al 2008).

Clinical Bottom Line

Milk or a special medium used for storage and transport of avulsed teeth improves the successful replantation rate. Further studies are recommended.

Level of Evidence

Level 3 - Small numbers of small studies or great heterogeneity or very different population.

References

1. Mackie IC, Worthington HV. An investigation of replantation of traumatically avulsed permanent incisor teeth. British Dental Journal 1992; 172 (1): 17-20.
2. Nordenvall KJ Milk as storage medium for exarticulated teeth: report of case. Journal of Dentistry for Children. 1992: 59 ( 2):150-5.
3. Kinoshita S, Kojima R, Taguchi Y, Noda T. Tooth replantation after traumatic avulsion: a report of ten cases. Dental Traumatology 2002: 18 (3): 153-6.
4. Blomlof L Storage of human periodontal ligament cells in a combination of different media. Journal of Dental Research 1981: 60 (11):1904-6.
5. Filippi C, Kirschner H, Filippi A. Pohl Y. Practicability of a tooth rescue concept--the use of a tooth rescue box. Dental Traumatology 2008: 24 (4):422-9.
6. Martin MP, Pileggi R. A quantitative analysis of Propolis: a promising new storage media following avulsion. Dental Traumatology 2004: 20 (2): 85-9.
7. Mackie IC, Worthington H. Investigation of the children referred to a dental hospital with avulsed permanent incisor teeth. Endodontics & Dental Traumatology 1993: 9 (3):106-10,
8. de Carvalho Rocha MJ, Cardoso M. Reimplantation of primary tooth--case report. Dental Traumatology 2008: 24 (4): e4-10.
9. Bhambhani SM. Treatment and prognosis of avulsed teeth. A discussion and case report. Oral Surgery, Oral Medicine, Oral Pathology 1993: 75 (2): 233-8.
10. Blomlof L, Otteskog P. Viability of human periodontal ligament cells after storage in milk or saliva. Scandinavian Journal of Dental Research 1980: 88 (5): 436-40.
11. Ashkenazi M, Sarnat H, Keila S. In vitro viability, mitogenicity and clonogenic capacity of periodontal ligament cells after storage in six different media. Endodontics & Dental Traumatology 1999: 15 (4):149-56.
12. Lekic PC, Kenny DJ, Barrett EJ. The influence of storage conditions on the clonogenic capacity of periodontal ligament cells: implications for tooth replantation. International Endodontic Journal 1998: 31 (2):137-40.
13. Andreasen JO, Hjorting-Hansen E Replantation of teeth 1. Radiographic and clinical study of 110 human teeth replanted after accidental loss Acta Odontol Scand 1966; 24:263-286
14. Andreasen JO, Borum MK, Jacobsen HL, Andreasen FM Replantation of 400 avulsed permanent incisors. 2. Factors related topulpal healing. Endodontics & Dental Traumatology 1995; 11:59-68.
15. Andreasen JO, Borum MK, Jacobsen HL, Andreasen FM. Replantation of 400 avulsed permanent incisors. 4. Factors related to periodontal ligament healing. Endodontics & Dental Traumatology 1995; 11:76-89