Experimental investigation of the temperature during bone drilling using thermocouples and numerical finite element analysis

Figures & data

Figure 1. PUR block with designed holes for thermocouples in the direction perpendicular to the drilling direction.

Figure 2. Different drills used in this study: Drill no. 1610.928b Ihde Dental (a), Drill no. 1610.928b-k Dentamechanik (b), Drill no. 1610.914d Ihde Dental (c), Drill no. 1610.914d-k Dentamechanik (d).

Table 1. Table of material properties for used stainless alloy 1.4112 and polyurethane foam (PUR).

Material	Density (k.gm^–3)	Thermal conductivity (W.m^–1.K^–1)	Thermal expansion (10^–6.K^–1)	Specific heat (J.kg^–1.K^–1)	Young’s modulus (MPa)	Poisson’s ratio (–)	Friction coefficients (–)
PUR foam	640	0.02216	63	1,500	759	0.3	0.7(20°), 0.3(50°), 0.2(100°)
Alloy 1.4112	7,700	24	10	460	200,000	0.3

Table 2. Experimentally detected temperature of four different drills during three rotational speeds.

Drill #	Revolutions (rpm)	Maximal temperature on thermocouple (°C) (±SD)	Maximal IR# Temperature (°C) (±SD)
1610.928b	800	47.9 (±3.8)	115.4 (±2.8)
	3,000	44.9 (±2.2)	142.3 (±3.7)
	5,000	40.6 (±3.2)	127.5 (±3.1)
1610.928b-k	800	37.1 (±4.2)	84.4 (±3.8)
	3,000	45.8 (±3.8)	113.6 (±3.4)
	5,000	64.5 (±5.2)	138.9 (±3.2)
1610.914d-k	800	–	–
	3,000	87.6 (±5.2)	220.7 (±3.6)
	5,000	129.3 (±3.4)	265.2 (±2.8)
1610.914d	800	40.8 (±4.2)	77.2 (±3.2)
	3,000	50.1 (±3.8)	94.7 (±3.4)
	5,000	47.1 (±3.7)	46.2 (±2.8)

Maximal temperature of thermocouple and maximal temperature of drill cutting edge during perforating the PUR block. Version without cooling. Mean values with standard deviation (±SD).

Table 3. Experimentally detected temperature of four different drills during three rotational speeds.

Drill #	Revolutions (rpm)	Maximal temperature on thermocouple (°C) (±SD)	Maximal IR# Temperature (°C) (±SD)
1610.928b	800	35.0 (±3.2)	94.5 (±3.8)
	3,000	37.2 (±2.8)	123.0 (±3.8)
	5,000	42.6 (±2.4)	129.1 (±3.8)
1610.928b-k	800	29.1 (±3.8)	62.9 (±3.8)
	3,000	28.4 (±3.9)	76.6 (±3.8)
	5,000	31.9 (±3.2)	81.8 (±3.8)
1610.914d-k	800	–	–
	3,000	47.7 (±3.3)	139.9 (±1.8)
	5,000	50.9 (±2.6)	141.8 (±2.2)
1610.914d	800	28.0 (±2.7)	57.5 (±2.1)
	3,000	30.1 (±2.2)	77.4 (±2.8)
	5,000	33.4 (±3.1)	77.0 (±2.4)

Maximal temperature of thermocouple and maximal temperature of drill cutting edge during perforating the PUR block. Version with cooling. Mean values with standard deviation (±SD).

Figure 3. Figures of temperature T (°C) distribution on IhdeDental 1610.928b drill (left) and PUR foam (middle), Von Misses reduced stress σ_red (MPa) distribution on the drill (right).

Figure 4. Figures of temperature T (°C) distribution on Dentamechanik 1610.928b-k drill (left) and PUR foam (middle), Von Misses reduced stress σ_red (MPa) distribution on the drill (right).

Figure 5. Figures of temperature T (°C) distribution on IhdeDental 1610.914d drill (left) and PUR foam (middle), Von Misses reduced stress σ_red (MPa) distribution on the drill (right).

Figure 6. Figures of temperature T (°C) distribution on Dentamechanik 1610.914d-k drill (left) and PUR foam (middle), Von Misses reduced stress σ_red (MPa) distribution on the drill (right).

Table 4. Results from numerical analyses.

Drill model	Maximal temperature T (°C)		Von Misses stress
	Drill	PUR foam (2.5 mm distance from axis)	σred (Mpa)
IhdeDental 1610.928b	120.9	52.9	604.5
Dentamechanik 1610.928b-k	90.6	44.5	290.8
IhdeDental 1610.914d	89.0	45.9	336.1
Dentamechanik 1610.914d-k	133.2	130.6	552.1

Table 6. Maximal temperatures (°C) obtained from experimental measurements and FE analyses.

Drill models	Maximal temperature (°C) on drill tip		Maximal temperature on thermocouple/(2.5 mm distance from axis) (°C)
	Experiment IR camera	FEM analyses	Experiment thermocouple	FEM analyses
IhdeDental 1610.928b	115.4	120.9	47.9	50.2
Dentamechanik 1610.928b-k	84.4	90.6	37.1	40.6
IhdeDental 1610.914d	77.2	88.6	40.8	44.6
Dentamechanik 1610.914d-k	–	133.2	–	130.6

Data availability statement

Data about the article are available at DOI: 10.6084/m9.figshare.14173457