Contact sensitization to metals in dental exposures in Bulgaria

Figures & data

Table 1. Gender characteristics of the studied population.

	Gender
Group	Female [n / (%)]	Male [n / (%)]	Total [n /(%)]
Occupationally exposed dental professionals	18 (64.3%)	10 (35.7)	28 (21.9%)
Students from dental technician school	29 (76.3%)	9 (23.7)	38 (29.7%)
Students of dental medicine	25 (62.5%)	15 (37.5)	40 (31.3%)
Patients without occupational exposure	17 (77.3%)	5 (22.7)	22 (17.2%)
Total	89 (69.5%)	39 (30.5%)	128 (100.0)

Table 2. Interpretation key of skin patch test results based on International Contact Dermatitis Research Group.

Symbol	Meaning
(–)	Negative reaction
?	Doubtful reaction
+	Weak positive reaction (non-vesicular)
++	Strong positive reaction (oedematous or vesicular)
+++	Extreme positive reaction (ulcerative or bullous)
IR	Irritant reaction

Figure 1. Incidence of positive skin patch tests to the investigated metals in the whole studied population.

Table 3. Incidence of positive skin patch test reactions to potassium dichromate, palladium(II)chloride and gold(I)sodium thiosulfate dehydrate.

	Skin patch test reactions to potassium dichromate
Target group	Negative reaction [n (%)]	Positive reaction [n (%)]	Total n
Dental professionals	23 (23.7)	5 (16.1)	28
Student from dental technician school	31 (32.0)	7 (22.6)	38
Students of dental medicine	23 (23.7)	17 (54.8)	40
Occupationally unexposed patients	20 (20.6)	2 (6.5)	22
Total	97 (100)	31 (100)	128
	Skin patch test reactions to palladium(II)chloride
Target group	Negative reaction [n (%)]	Positive reaction [n (%)]	Total n
Dental professionals	19 (20.2)	9 (26.5)	28
Student from dental technician school	33 (35.1)	5 (14.7)	38
Students of dental medicine	24 (25.5)	16 (47.1)	40
Occupationally unexposed patients	18 (19.1)	4 (11.8)	22
Total	94 (100)	34 (100)	128
	Skin patch test reactions to gold(I)sodium thiosulfate dehydrate
Target group	Negative reaction [n (%)]	Positive reaction [n (%)]	Total n
Dental professionals	21 (24.1)	7 (17.1)	28
Student from dental technician school	25 (28.7)	13 (31.7)	38
Students of dental medicine	21 (24.1)	19 (46.3)	40
Occupationally unexposed patients	20 (19.1)	2 (9.1)	22
Total	87 (100)	41 (100)	128

Figure 2. Incidence of positive skin patch test reactions in the group of dental professionals.

Figure 3. Incidence of positive skin patch test reactions in the group of dental students.

Figure 4. Incidence of positive skin patch test reactions in the group of students from the dental technician school.

Figure 5. Incidence of positive skin patch test reactions in the group of dental patients.

Table 4. Gender distribution of positive skin patch tests to palladium(II)chloride and aluminium(III)chloride hexahydrate.

	Gender
Skin patch test reactions to palladium(II)chloride	Women n (%)	Men n (%)	Total n	χ^2 = 4.071 p = 0.044
Negative reaction	70 (78.7)	24 (61.5)	94	OR = 2.303
Positive reaction	19 (21.3)	15 (38.5)	34	CI = 1.014–5.231
Total	89	39	128
	Gender
Skin patch test reactions to aluminum chloride hexahydrate	Women n (%)	Men n (%)	Total n	χ^2 = 3.987 p = 0.046
Negative reaction	77 (86.5)	28 (71.8)	105
Positive reaction	12 (13.5)	11 (28.2)	23
Total	89	39	128