Indicating teeth cleaning time

1. A method of controlling a toothbrush, the method comprising:

measuring an actual cleaning time of a first teeth cleaning process using a time determination device of the toothbrush;

comparing the actual cleaning time of the first teeth cleaning process to a standard cleaning time using an evaluation device of the toothbrush; and

determining a target cleaning time of a second, subsequent teeth cleaning process using a control device of the toothbrush, wherein the target cleaning time of the second teeth cleaning process is the standard cleaning time plus additional time when the actual cleaning time of the first cleaning process is less than the standard cleaning time.

2. The method of claim 1 , wherein the additional time added to the standard cleaning time is a fixed time such that, when the actual cleaning time of the first cleaning process is less than the standard cleaning time by any of a plurality of different amounts of time, the target cleaning time for the second teeth cleaning process is the standard cleaning time plus the fixed time.

3. The method of claim 2 , wherein the fixed time is at least about 15 seconds.

4. The method of claim 3 , wherein the fixed time is about 30 seconds.

5. The method of claim 1 , wherein the additional time added to the standard cleaning time is equal to a deviation of the actual cleaning time of the first cleaning process from the standard cleaning time when the deviation is less than or equal to a deviation limit.

6. The method of claim 5 , wherein the additional time added to the standard cleaning time is a fixed time for any deviation of the actual cleaning time of the first cleaning process from the standard cleaning time that is greater than the deviation limit.

7. The method of claim 6 , wherein the deviation limit is about 90 seconds, and the fixed time is about 90 seconds.

8. The method of claim 1 , wherein the additional time added to the standard cleaning time is equal to the deviation of the actual cleaning time of the first teeth cleaning processes from the standard cleaning time plus the deviation of an actual cleaning time of a third teeth cleaning process from the standard cleaning time, wherein the third teeth cleaning process preceded the first teeth cleaning process.

9. The method of claim 1 , wherein the additional time is only added to the standard cleaning time when the actual cleaning time of the first teeth cleaning processes differs from the standard cleaning time by a minimum time differential.

10. The method of claim 1 , wherein the target cleaning time of the second teeth cleaning process is the standard cleaning time when the actual cleaning time of the first cleaning process is greater than or equal to the standard cleaning time.

11. The method of claim 1 , wherein the standard cleaning time is about 120 seconds.

12. The method of claim 1 , wherein the control device only determines the target cleaning time of the second teeth cleaning process based on the comparison of the actual cleaning time and the target cleaning time of the first teeth cleaning process when the actual cleaning time of the first teeth cleaning process exceeds a minimum cleaning time.

13. The method of claim 12 , wherein the minimum cleaning time is about 30 seconds.

14. The method of claim 1 , further comprising determining a target cleaning time for the first cleaning process based on a comparison of an actual cleaning time and a target cleaning time of a third teeth cleaning process that preceded the first cleaning process.

15. The method of claim 1 , wherein the first and second cleaning processes occur

at least about one hour apart from one another.

16. The method of claim 1 , further comprising activating an output device of the toothbrush to alert a user when the target cleaning time of one of the cleaning processes has ended.

17. The method of claim 16 , wherein the output device is an audible alarm.

18. The method of claim 1 , wherein a determined deviation of the actual cleaning

time of the first cleaning process from the standard cleaning time is stored in memory of the toothbrush.

19. The method of claim 18 , wherein the control device accesses the memory to determine the target cleaning time of the second teeth cleaning process.

20. The method of claim 1 , wherein the toothbrush emits a sub-target warning signal if the actual cleaning time of the first teeth cleaning process is determined to be less than the standard cleaning time.

21. The method of claim 1 , wherein the actual cleaning time of the first teeth cleaning process is determined as a time interval between an operator activating and deactivating the toothbrush.

22. The method of claim 1 , wherein the actual cleaning time of the first teeth cleaning process continues to be measured upon temporary interruption of operation of the toothbrush if the interruption is less than a minimum interruption time limit.

23. A method of controlling a toothbrush, the method comprising:

measuring an actual cleaning time of a first teeth cleaning process using a time determination device of the toothbrush;

comparing the actual cleaning time of the first teeth cleaning process to a target cleaning time of the first cleaning process using an evaluation device of the toothbrush; and

determining a target cleaning time of a second, subsequent teeth cleaning process using a control device of the toothbrush, wherein

the target cleaning time of the second teeth cleaning process is equal to a standard cleaning time plus additional time when the actual cleaning time of the first cleaning process is less than the target cleaning time of the first cleaning process; and

the target cleaning time of the second teeth cleaning process is equal to the standard cleaning time when the actual cleaning time of the first cleaning process is greater than or equal to the target cleaning time of the first cleaning process.

24. The method of claim 23 , wherein the additional time added to the standard cleaning time is a fixed time such that, when the actual cleaning time of the first cleaning process is less than the target cleaning time of the first cleaning process by any of a plurality of different amounts of time, the target cleaning time for the second teeth cleaning process is the standard cleaning time plus the fixed time.

25. The method of claim 23 , wherein the additional time added to the standard cleaning time is equal to a deviation of the actual cleaning time of the first cleaning process from the target cleaning time of the first cleaning process when the deviation is less than or equal to a deviation limit.

26. The method of claim 25 , wherein the additional time added to the standard cleaning time is a fixed time when the deviation is greater than the deviation limit.

27. The method of claim 23 , wherein the additional time is only added to the standard cleaning time when the actual cleaning time of the first teeth cleaning processes differs from the target cleaning time of the first teeth cleaning process by a minimum time differential.

28. The method of claim 23 , wherein the target cleaning time of the first teeth cleaning process is the standard cleaning time.

29. The method of claim 23 , wherein the control device only determines the target

cleaning time of the second teeth cleaning process based on a comparison of the actual cleaning time and the target cleaning time of the first teeth cleaning process when the actual cleaning time of the first teeth cleaning process exceeds a predetermined minimum cleaning time.

30. The method of claim 23 , further comprising determining the target cleaning time of the first cleaning process based on a comparison of an actual cleaning time and a target cleaning time of a third teeth cleaning process that preceded the first cleaning process.

31. The method of claim 23 , wherein the actual cleaning time of the first teeth cleaning process continues to be measured upon temporary interruption of operation of the toothbrush if the interruption is less than a predetermined minimum interruption time limit.

32. A toothbrush, comprising:

a tooth cleaning element; and

a controller that is configured to

measure an actual cleaning time of a first teeth cleaning process;

compare the actual cleaning time of the first teeth cleaning process to a target cleaning time of the first cleaning process; and

determine a target cleaning time of a second, subsequent teeth cleaning process by adding additional time to a standard cleaning time when the actual cleaning time of the first cleaning process is less than the target cleaning time of the first cleaning process.