1. 25th IAPD Biennial Congress Glasgow
Preformed Metal Crowns for treating primary molars in a General Practice setting – 24 months G.D Taylor, K Perry & R.R Welbury
Greig D Taylor
25th IAPD Biennial Congress Glasgow
Saturday 4th July 2015

2. Introduction Historically...
…conventional glass ionomer was used to treat carious primary molars in my VT practice
However, after this service evaluation…
…non infected carious primary molars are now treated with Hall Preformed Metal Crowns (PMCs)
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

3. Background
BSPD “National Clinical Guidelines in Paediatric Dentistry: stainless steel preformed crowns for primary molars” highlights:
“…preformed metal crowns outperform direct plastic restorations when restoring multi-surface carious primary molars1”
A recent 5 year randomised control study showed statistically significant beneficial results for pulpal health and longevity when a PMC is cemented over an unprepared carious tooth without LA (Hall crown) in comparison to placement of conventional direct restorations2
Our body’s guideline suggets that SSC outperform direct plastic restorations when restoring multi-surface caries. This was used as the standard to which I compared my results to.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

4. Aims
To assess the effect on primary caries and the patient experience, when introducing Hall PMCs as an option of treating carious primary molars in a general dental practice setting
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

5. Design
All Hall PMCs were placed by a single operator, without the use of local anaesthesia, in accordance with SDCEP guidelines3 over a 6 month period
A data collection tool measured clinical and radiographic outcomes at baseline and 6 monthly intervals for a period of 24 months
Consent was obtained from the child’s parent for involvement in this project
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

6. Design Figure 1 – Baseline Data Collection
pre-operative assessment of the patient,
both clinically and radiographically (if applicable);
assessment of whether the patient would accept conventional treatment under local anaesthetic;
if any procedure was required to help the placement of a stainless steel crown;
how safely the stainless steel crown was placed;
if there was any occlusal discrepancy after placement;
a subjective assessment of how the patient coped.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

7. Design Figure 2 – Six Monthly data collection
Self reported history from patient;
Clinical evaluation of tooth (if still in place; any evidence of infection, pain, mobiltiy, damage to ssc, replaced)
Radiographic evaluation
Overall success – clinician, parent and patient.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

8. Results N = 34 Hall PMCs placed
Total = 17 patients (9 males : 8 females)
Mean: 8.1years
Carried out in Maryhill, Glasgow; Scottish Index of Multiple Deprivation (1 most deprived)
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

9. Results Pre-Treatment Assessment Percentage
Patients who would not tolerate LA or high speed drill
44.1%
No reported symptoms or clinical signs of Reversible/Irreversible pulpitis
100%
Evidence of Marginal breakdown (Range: 2mm-5mm)
35%
Number of bitewings taken pre-operatively
79%
Extent of caries “less than halfway” into dentine on pre-operative bitewing
56%
Cases where combination of safety modalities used during placement
(child sat upright; gauze to protect throat; PMC secured by tape)
4 patients were not able to tolerate the digital sensor
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

10. Results Placement of Preformed Metal Crown
91% of patients (17 patients) showed none or very mild signs of discomfort during placement of SSC. No patient showed signs of signifcant and unacceptable signs of discomfort.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

11. Results 6 Month Assessment 97% of Hall PMCs were in situ
10 patients reported mild difficulty in eating immediately post placement
One case of secondary caries detected
One Hall PMC had to be re-cemented after 6 weeks
One Crown was extracted due to severe dental trauma
Only 30 stainless steel crowns could be assessed as issues with digital sensor tolerance was noted in a few cases.
A few cases should early/moderate signs of physiological root resorption but minimal clinical mobility;
One case showed signs of secondary caries around the margin…this was removed and replaced.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

12. Results 12 Month Assessment 71% Hall PMCs were in situ
26% Hall PMCs exfoliated naturally
1 patient reported mild difficulty eating
One further case of secondary caries noted
One case was repaired due to wear
Normal physiological resorption was observed radiographically
Only 30 stainless steel crowns could be assessed as issues with digital sensor tolerance was noted in a few cases.
A few cases should early/moderate signs of physiological root resorption but minimal clinical mobility;
One case showed signs of secondary caries around the margin…this was removed and replaced.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

13. Results 18 Month Assessment 56% of Hall PMCs were in situ
38% Hall PMCs had exfoliated naturally.
1 patient reported mild difficulty eating
One crown was extracted due to an irreversible pulpitis
One case of secondary caries
Remaining Hall PMCs radiographed showed signs of normal physiological resorption
Only 30 stainless steel crowns could be assessed as issues with digital sensor tolerance was noted in a few cases.
A few cases should early/moderate signs of physiological root resorption but minimal clinical mobility;
One case showed signs of secondary caries around the margin…this was removed and replaced.
Greig D Taylor IAPD Biennial Congress Glasgow 2015

14. Results 24 Month Assessment 41% of Hall PMCs placed were in situ
53% had exfoliated naturally
3 patients reported mild difficulty eating
No clinical signs of infection/mobility was noted in any of the remaining teeth
A varied level of normal physiological resorption was observed
Only 30 stainless steel crowns could be assessed as issues with digital sensor tolerance was noted in a few cases.
A few cases should early/moderate signs of physiological root resorption but minimal clinical mobility;
One case showed signs of secondary caries around the margin…this was removed and replaced.
Greig D Taylor IAPD Biennial Congress Glasgow 2015

15. Overall Success of Hall PMCs
Results
Overall Success of Hall PMCs
6 months
12 months
18 months
24 months
Operator
94%
97%
100%
Parent
Patient
I was not happy with the secondary caries, however this was not replaced as the tooth showed signs that it would exfoliate in the near future.
All the patients and parents were happy with the SSC and felt they were successful.
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

16. Discussion Recognised minor failures: failure of cementation1,2,6
occlusal wear1,2,6
recurrent caries1,2,6
All of which were managed without sacrificing the tooth
2 Major failures were unavoidable
Greig D Taylor IAPD Biennial Congress Glasgow 2015

17. Discussion
Patients and parents reported the treatment to be a success both initially and at subsequent visits
The majority of patients accepted the placement of a Hall PMCs with minimal or no discomfort with Bell et al5 showing similar results
Discomfort was anecdotally noted:
Initially to the “tightness around the gingivae”
Laterally to the exfoliation process
Greig D Taylor IAPD Biennial Congress Glasgow 2015

18. Implementation of Findings
I disseminated the initial results at a monthly practice meeting
Further results where shared at regular intervals
I then ran a 30 minute presentation/demonstration session for all the staff within the practice and subsequently changed the practice protocol
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

19. Conclusion Hall PMCs are:
An effective and successful way to treat carious primary molars in general dental practice
Facilitate the transition of the child to the permanent dentition with minimal pain and sepsis
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015

20. References
SA Kindelan, P Day, R Nichol, N Willmott, SA Fayle, Stainless Steel preformed crowns for primary molars. Int J Paed Dent 2008; 18 (suppl. 1): 20-28
Innes NPT, Evans DJP, Stirrups DR. (2011) Sealing caries in primary Molars: Randomised Control Trial, 5 year Results. J Dent Res 90:
Scottish Dental Clinical Effectiveness Programme. Guidelines: Prevention and Management of Dental Caries in Children. SDCEP, April 2010
Inness NPT, Ricketts D, Evans DJP. Preformed metal crowns for decayed primary molar teeth. Cochrane Database of Systematic Reviews 2007
SJ Bell, AG Morgan, Z Marshman, HD Rodd. Child and parental acceptance of preformed metal crowns. European Archives of Paediatric Dentistry. 11(Issue 5) 2010
NPT Innes, DR Stirrups, DJP Evans, N Hall, M Leggate. A novel technique using preformed metal crowns for managing carious primary molars in general practice – A retrospective analysis. British Dental Journal ; 200:
Greig.D.Taylor IAPD Biennial Congress Glasgow 2015