Business Process SimulationProject : Dental Clinic service

(Tool: Arena Simulation Software)Mr. Sok kimseng

Problem DescriptionDental clinic manager wants to fire a few staffs because he observed that theresource (dentists and dental assistant) is over capacity requirement. And also, he wantsTo cut expense of labor cost. However, he still want to provide the bestquality of treatment, services, and the lowest price for overall patients bothlocal and international. So he wants to know the effect of cutting the numberof dentist or dental assistants. The Bright Smile dental clinic: Personnel: three dentists (Two are active employees and One is part-time employee),

four dental assistants, one receptionist, and one secretary. Machine Capacity: the clinic equipped with one x-ray machine, one intraoral

radiographs unit, and one extra-oral panoramic radiographs unit for providing oral healthcare service to patients.

Question and KPIsQuestions: Does it effect to patients number out or service qualityif dental clinic manager wants to fire one dental assistant and one part-timedentist? The main objective of this project is to study staffing modification bymodifying the number of resource so that manager can determine the impactof this modification on the performance metrics of the dental clinic in deliveryoral healthcare service by using Arena simulation software.

KPIs: We have to measure some performance metrics such as:a. The rejected percent when dentists are not available for providing service to

the patientsb. The patient total time in system (dental clinic) for first and return patientsc. Resource Utilization (Personnel and dental chair)

Dental Clinic Layout

South

North

WestEastCRE

Waiting Room

IN Treat 2

CDRTR

CO

D&P Treat 3

Treat 1Treat 5Treat 6

Treat 4

Data Input Entity: Patients (First and Return Patients)Process:

Queue: FIFO Resource

Process ID Process Resource ID Process time (minutes)

Interarrival of patients NORM(43.7,14.1)CRE Check-in with receiptionist RE TRIA(2,3,4)CDR Check-in for first visit with dentist DR and DC TRIA(10,12,15)CDR Check-in for return visit with dentist DR and DC TRIA(3,5,8)TR Taking radiograph DA TRIA(3,4,5)IN Oral Health Instruction DA TRIA(10,15,20)

D&P Diagnosis & Planning DR and DC TRIA(2,4,10)Treat 1 Filling treatment DR, DA and DC TRIA(30,40,50)Treat 2 Sealing treatment DR, DA and DC TRIA(20,30,40)Treat 3 Cleaning treatment DR, DA and DC TRIA(20,30,40)Treat 4 Crown treatment DR, DA and DC TRIA(45,60,70)Treat 5 Extraction treatment DR, DA and DC TRIA(30,45,60)Treat 6 Check-up DR, DA and DC TRIA(5,10,15)

CO Check-out for first visit RE TRIA(5,8,12)CO Check-out for return visit RE TRIA(1,2,3)

Resource ID Resoruce CapacityDR Dentist 3DA Dental Assistant 4RE Receptionist 1DC Dental Chair 2

Conceptual Flow

Check-in

Meet dentist

Meet dental assistant

Meet dentist and dental assistant to do preventive and corrective

dental treatment

Patients Arrive

Patients leave or return to clinic again based on schedule appointment

- Dental assessment,- Diagnosis & planning

-Take radiograph (If needed) - Oral health instruction

Conceptual ModelPatien

ts Arrival

First Visit

Return Visit

CDR

TR

D&R

IN

Treat 1

Treat 3

Treat 6Treat 5Treat 4

CO

40%

60%

30%

15%

55%30%

15%

15%10%20%

NORM(43.7,14.1) First Visit: TRIA(10,12,15)Return Visit: TRIA(3,5,8)

TRIA(3,4,5) TRIA(10,15,20)

TRIA(2,4,10)

TRIA(30,40,50)

TRIA(20,30,40)

TRIA(45,60,70)

TRIA(30,45,60)

TRIA(5,10,15)

Treat 2

TRIA(20,30,45)

CRETRIA(2,3,4)

10%

Patients Leave

First Visit: TRIA(5,10,15)Return Visit: TRIA(1,2,3)

First Visit Time in system

Return Visit Time in system

First Visit number

Return Visit

number

RE=1 DR=1,DC=1

DA=1 DA=1

DR=1,DC=1

DR=1,DA=1, DC=1

RE=1

ARENA Model

Run Setup Replication Percent rejected

1 26.666

2 18.75

3 23.529

4 25

5 29.411

6 29.411

7 15.374

8 6.666

9 25

10 35.294

Sample Mean 23.5101

Sample standard deviation 7.716732384

95% Confidence Interval Half Width 5.519834287

Minimum Summary output value 6.666

Maximum Summary output value 35.294

Error in the point estimate 23.47%

Desired value h 2

First approximation 57.18985953

Second approximation 76.17142639

Simulation run time: Terminating simulation (TNOW > 600 && Total WIP == 0) Number of replication

Based on statistical analysis, number of replication should be 80 times.

Evaluating scenarios with PAN

Discussion Percent rejected: According to box and whisker plot with error

tolerance 10%, the percent rejected of scenario 10, scenario 14, and scenario 18 are 11.12%, the same level.

Discussion Resources: According to the table below, the scenario 18 is the best in

term of number of resource usage and resource utilization in the clinic. Resource Utilization

DA DC DR

Scenario 10

0.447

0.25 0.597

Scenario 14

0.447

0.337

0.597

Scenario 18

0.447

0.50 0.597Resource

sDA DC DR

Scenario 10

2 4 4

Scenario 14

2 3 4

Scenario 18

2 2 4

Discussion Average total time in the clinic:The average total time in dental clinic system is the same in scenario 10, 14,

and 18. Total time in system for first visit patient is 75.821minutes. Total time in system for return visit patient is 59.621 minutes.

ConclusionRegarding to the question and discussion, we conclude and

recommend as following: Scenario 18 is the best. Dental clinic manager could not fire dentist if he considers about

the percent rejected or service level. In contrast, the manager should hire one more dentist so that the

percent rejected will be reduced from 25.51% to 11.120% an well as the average total time in the clinic will be reduced from 93.202 minutes to 75.821 minutes for first visit patients and from 77.908 minutes to 59.621minutes for return visit patients.

On the other hand, the resource utilization of dental assistant is low (only 18.6%). we also recommend that dental assistants should be reallocated and assigned to other tasks in case of manager doesn’t want to fire them. We can add more tasks for them in order to use this resource efficiently.

Thank you!!!