Dental sterilizer monitoring · United States
How to read and record a spore test result
A spore test reads negative, positive or invalid, and the result counts only when the control grows: the record writes the control's result as “growth = valid”.
Whatever the result, write it down: results of biological monitoring should be recorded, and the records kept long enough to comply with state and local regulations (CDC, 2003 dental infection-control guidelines).
Negative, positive or invalid
Every spore test ends in one of three results. The names below describe what the test and its control show; the sentences that tell you what to do carry their sources.
| Result | What the record shows | What it means | What happens next |
|---|---|---|---|
| Negative | No growth in the test indicator. | The test passed. | The result is written down and kept (CDC, 2003 dental infection-control guidelines). |
| Positive | Growth in the test indicator. | The test failed: this is the cycle that produced the failure. | Repeat the spore test immediately, loading the sterilizer correctly and using the same cycle that produced the failure, and take the sterilizer out of service (CDC, 2003 dental infection-control guidelines). |
| Invalid | The control does not grow. | The result cannot count: growth of the control is what makes a result valid. | The source pack for this guide does not say what an invalid result obliges. Dental Logbook will flag the test so the office can decide, and record what it decided. |
The control must grow first
A spore test is two indicators, not one: a biological indicator with a matching control, meaning a biological indicator and a control from the same lot number (CDC, 2003 dental infection-control guidelines).
The control is not processed through the sterilizer; it is incubated together with the test indicator (CDC, 2003 dental infection-control guidelines).
The control is why a result can count at all. In the Dental Logbook record, the control's result is written “growth = valid”: a spore test is valid only when the control grows. Until the control grows, the test indicator's reading proves nothing, so read the control first.
The pack behind this guide says what to write down about the control; it does not say what to do when the control fails to grow. Dental Logbook will mark such a result invalid and leave the next step to the office.
What to record
Results of biological monitoring should be recorded, and sterilization monitoring records, mechanical, chemical and biological, retained long enough to comply with state and local regulations (CDC, 2003 dental infection-control guidelines).
A good spore test record writes down more than the result:
- which sterilizer and cycle type the test rode in, and in which load — a routine load or an implant load;
- the biological indicator's product, lot number and expiry date;
- whether the control came from the same lot, and the control's result;
- the method: in-office, with the incubation start and read time, or mail-in, with the lab, the date sent, the report ID and the date received;
- the result — negative, positive or invalid — and the result date;
- who entered the result, with the lab report attached to the entry.
Dental Logbook will keep these fields for every spore test. It keeps no patient names in a spore test record.
After a positive result
A positive result starts one repeat test and one review, and the guideline gives both in a single breath:
“the spore test should be repeated immediately after correctly loading the sterilizer and using the same cycle that produced the failure. The sterilizer should be removed from service, and all records reviewed of chemical and mechanical monitoring since the last negative BI test.” (CDC, 2003 dental infection-control guidelines)
The steps after that repeat belong in a page of their own. Use the failed-test guide and its printable record for the investigation, and the spore test log to keep the results themselves:
- The failed-test guide: what to do when a dental spore test fails — the full procedure after a positive result.
- The printable failed spore test record — one sheet for the out-of-service decision, the repeat test and the return to service.
- The free spore test log — a printable sheet for each result, its control and its lot.
The exact words this page relies on
Every rule sentence above comes from one of these four rows of our source pack. Nothing else on this page is a rule.
“Monitor sterilizers at least weekly by using a biological indicator with a matching control (i.e., biological indicator and control from same lot number)”
“A control BI, from the same lot as the test indicator and not processed through the sterilizer, should be incubated with the test BI”
“the spore test should be repeated immediately after correctly loading the sterilizer and using the same cycle that produced the failure. The sterilizer should be removed from service, and all records reviewed of chemical and mechanical monitoring since the last negative BI test.”
“Results of biological monitoring should be recorded and sterilization monitoring records (i.e., mechanical, chemical, and biological) retained long enough to comply with state and local regulations.”
Where our sources stop
What the pack is silent on matters as much as what it says. So, plainly:
- it does not say what to do when the control fails to grow; it marks a result without control growth as invalid and stops there;
- the state rules in the pack add nothing about what a spore test record must contain; on record contents they are silent;
- the sources behind the later steps do not agree on the cycles that qualify a sterilizer again after a repeat positive, so this page does not pick a side;
- no source read for this pack requires patient names in a sterilizer record.
This page is not legal advice; check your state board's current rules.
Keep every spore test result in one record
Dental Logbook is being built to keep each spore test result with its control, lot and load, for US dental offices. Pilot offices shape what it records.
Dental Logbook is in development: join the free pilot