Veterans Administration Cooperative Studies Project 147: Association of metallic taste with metal ceramic Participants
of CSP Nos.
147/242*
and Harold
F. Morris,
D.D.S.,
No. alloys
M.S.**
VeteransAdministrationMedicalCenter,Ann Arbor, Mich. We examined patients to find out whether they noticed the prevalence of metallic taste and set out to determine the association of metallic taste with demographic, medical, and dental factors. Data were collected as part of a Veterans Administration Cooperative Study investigating the suitability of alternative metal ceramic alloys as substitutes for alloys that contain gold. Crowns and fixed partial dentures were made from control and alternative alloys for accepted volunteer patients. A month after placement of the restorations and at regularly scheduled recall appointments, the patients were asked if they tasted a metallic flavor. Of the 2023 times the question was asked, 101 positive responses were given by 68 patients (46 reported metallic flavor once, and 22 reported it more than once). Results indicated that youth, sensitivity to heat and cold, bruxism, grinding, and an increasing number of restorative units were significantly related to metallic taste. For any given visit, about 5% of the patients reported tasting a metallic flavor regardless of the type of alloy that was used in the restoration. Metallic taste does not appear to be a problem with alternative alloys. (J PROSTHET DENT 1990;63:124-9.)
T
he mouth has a sophisticated arrangement of sensorimotorsystemsthat regulatemastication, salivation, swallowing,and speaking. Primarily a feeding apparatus, the mouth dependson the senseof taste to evaluate foods. A distorted senseof taste (dysgeusia)or a diminishedsense of taste (hypogeusia) can detract significantly from these functions. Approximately two million American adults have disordersof the sensesof taste and of smell.l Despite their prevalence, these disorders have largely been neglected by the medical community becausethe disorders are not fatal and are not considered serious handicaps. However, disordersof the senseof taste can present major problems,becausedietary habits, digestion,nutrition, and the palatability of food can all be affected. In severecases, disordersof the senseof taste can be highly disruptive and can causestress,anorexia, and depression.2 Several factors have been implicated in the etiology of dysgeusia.For example,the following factors are known to affect the sensesof both taste and smell:various endocrine disorders,cancer,nutritional deficiencies,radiation, aging, trauma, restorative dentistry, hygienic factors related to infected gingivae and teeth, craniofacial abnormalities,
Supportedby the VeteransAdministrationMedical Research Service/Cooperative StudiesProgramand the NationalInstitute of Dental Research,InteragencyContract No. lYOlDE-50004-00, and conductedby the VeteransAdministration CSPNos.147/242,DentalResearchGroup. *Completeauthorshipappearson last pageof article. **Study ChairmenandDirector,ClinicalResearch Centerfor RestorativeMaterials,Veterans AdministrationMedical Center; ClinicalAssociateProfessor,Universityof Michigan,School.of Dentistry,Ann Arbor, Mich. 10/l/16021
124
psychiatric disorders,and severalmedications.2-g Deficiencies in the sense of smell (dysosmia, hyposmia, and anosmia)can contribute to deficienciesin the senseof taste and in differentiation of flavor.2pg Metallic taste may specifically be causedin part by medications, especiallymedications used by the elderly.5 Metallic taste may alsoarise as a result of trauma to the chorda tympani nerve, which could be injured during various surgicalprocedures5ylo In addition, dental galvanism,the production of an electrical current between two dissimilar metals,is reported to lead to sensationsof metallic taste.l’ A common example of dental galvanismis the contact between a piece of aluminum foil and an amalgamrestoration.12 Studies of the associationof age and the senseof taste have yielded contradictory results. Ramsey5reported that the lossof taste buds with age is progressiveand continuous, whereasBradley9 reports a nearly constant level of taste buds until about the ageof 75, when the number decreasessignificantly. Bamsey5cited a resulting lossin the differentiation of flavor, whereasBradleys claims there is no evidence supporting a causalrelationship between loss of taste buds and decreasedtaste sensitivity. The role of oral hygiene in taste disordershas alsobeen reported. Hyde et a1.13 found that thorough tongue brushing generally increasedtaste thresholds in older adults. Langan and Yearick’* reported an improved senseof taste in an experimental group of elderly adults undergoingprofessionaloral hygiene therapy. Little researchhasbeenconducted on the associationof the useof tobacco or alcoholand altered sensationof taste. One study found that, with aging, smoking caused a progressivedeterioration in the taste threshold of men, but not of women.15 Finally, Henkin et a1.16have reported on a syndrome of
FEBRUARY1990 VOLUME63
NUMBER2
VA PROJECT
Table
I.
147:
METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Study alloys
II. Approximate alloys (weight 7%)
Table
Alloy
Manufacturer
chemical compositions Test
Test alloys Ceramalloy
11
Johnson & Johnson Dental Products Co. IL Windsor, N.J. Ticonium Co. Albany, N.Y. Austenal Dental, Inc., A Nobelpharma Co. Chicago, Ill. Williams Dental Co., Inc. Buffalo, N.Y.
Ticon Micro-Rand
NP2
W-l Control alloy Olympia
J.F. Jelenko & Co. Armonk, N.Y.
hypogeusia with dysgeusia, hyposmia, and dysosmia. Patients having this syndrome frequently report a bizarre history and display no objective signs, which have led many physicians to suggest psychiatric causes rather than gustatory or olfactory causes. Reported symptoms include tasting a perpetual sweet, sour, salty, bitter, or metallic flavor, as well as smelling a persistent foul odor. Patients have also reported vertigo, hearing loss, and unexplained hypertension. Because the cause of taste disorders is not well understood and often involves the interplay of a variety of factors, there are few established interventions for this condition. Persons with taste disorders can often achieve temporary relief by chewing gum or ice, rinsing with sodium bicarbonate or long-lasting sweeteners, or applying local anesthetics. Dietary supplementation with zinc sulfate has been found to be an effective treatment in some patients47 g,ltj In this study, we investigated the prevalence of one form of dysgeusia-metallic taste-and its association with several demographic, medical, and dental/oral variables in a patient population.
MATERIAL
AND
METHODS
The data for this analysis were collected as part of a Veterans Administ,ration Cooperative Study that was investigating the suitability of alternative alloys as substitutes for alloys containing gold that are used for fixed prosthodontic restorations. Volunteers were accepted into the clinical study if they required complete crowns, fixed partial dentures, or both and if they met a series of dental and medical eligibility criteria.i7 When patients accepted into the study required more than two restorations, a determination was made as to which two restorations would be included in the analyses. The additional restorations needed were inserted but were not included in the study comparisons. This allowed
TEE
JOURNAL
OF
PROSTHETIC
DENTISTRY
Elements Au Pd Ag In Ga Sn Ni Cr Be Si Mn MO B Al Fe
alloy
of study
Control
Ceramalloy II
Ticon
Micro-Bond NP2
0 0 0 0 0 0 71.5 19.0 0 4.0 0 4.5 0.5 0 0
0 0 0 0 0 0 71.0 17.0 1.0 0 3.0 4.0 0.5 3.5 0
0 0 0 0 7.5 0 66.0 13.5 0 0.8 0 7.0 0 0 5.0
W-l 0 53.5 37.5 0.5 0 8.5 0 0 0 0 0 0 0 0 0
alloy
Olympia 51.5 38.5 0 8.5 1.5 0 0 0 0 0 0 0 0 0 0
paired comparisons between the alloy containing gold (control) and the alternative (test) alloy. Within each pair of restorations, the assignment of control or test alloy was randomly made. The particular alternative alloy used was also assigned in a random fashion. Lists of the alloys studied and their approximate chemical compositions are provided in Tables I and II. One month after placement of the restorations, patients were observed, and baseline measurements were recorded. Patients were recalled at 6-month intervals for maintenance visits and at l-year intervals for evaluation of the restorations. At recall visits, patients were asked whether they tasted the presence of a metallic flavor and other pertinent questions. A total of 604 patients from VA hospitals in six cities were questioned for this study. Unless indicated, all analyses were carried out with the use of the chi-square test. Tables III and IV list the health factors and the demographic factors that were included in this investigation. Tables V and VI list the oral hygiene factors and the dental factors included in the analysis. These tables include the percentage of patients who tasted a metallic flavor.
RESULTS The question about metallic taste was asked 2023 times, and 68 patients gave 101 positive responses. Forty-six of the patients reported they tasted a metallic flavor once, while 22 patients reported tasting a metallic flavor more than once. Of the demographic variables evaluated, the prevalence of metallic taste was significantly, but inversely, related to age. Patients 30 years of age and younger reported metallic taste more often than those older than 30 0, = 0.025). The prevalence of metallic taste differed
125
MORRIS
Table
Health factors investigated in occurrence of metallic taste
III.
Factor
Health
factors
Use of penicillin or sulfonamides Use of anticoagulant drugs Use of cortisone drugs Use of tranquilizers Current medication Recent (last 1 - 2 months) medication Presence of liver disease Presence of “acid stomach” Presence of hiatal hernia Presence of ulcers Presence of “nervous condition” Presence of kidney disease Need for frequent urination Excessive thirst Presence of diabetes Recent change in health Presence of hives Presence of allergies Presence of hypertension Use of cigarettes Use of alcohol Table
ET AL
No. of patients
present Metallic taste
460 30 67 201
4 114 50 51 66 20 56 42 15 44 146 127 86 278 430
w
55
12.0 3.3 7.5 9.0 10.4 9.6 0.0 12.3 12.0 7.8 10.6 4.4 10.7 2.4 6.7
1 5 18 20 17 0 14 6 4 7 3 6
192 177
Factor
1 1
15 7 39 51
No. of patients
Metallic taste
144
13 67 63 50 45 51 68 54 62 64 61 65 62 67 67 64 47 53 61 29 17
574 537 401
397 424 600
490 553 553 537 584 548 561
589
9.1 14.4 11.8 8.1 14.0 11.9
4 21
not present
560 458 467 518 326 172
%
p Value
9.0 11.7
0.413 0.266 0.402 0.251 0.847 0.475
11.7 12.5 11.3 12.0 11.3 11.0 11.2 11.6 11.4 11.1 11.3 11.9 11.4 11.4 10.3 11.4 11.8 8.9 9.9
1.000 0.827
1.000 0.565
1.000 0.858
1.000 0.102 0.876 0.822 0.222
1.000 0.421 0.063 0.583
Demographic factors investigated in occurrence of metallic taste
IV.
Factor Demographic
factors
No. of patients
present Metallic
taste
96
p Value
Age (~4 >30 530
Race White Black Gender Male Female
0.025* 330 274
28 40
8.5 14.6
471 106
45 21
9.6
19.8
544 60
62 6
11.4 10.0
0.008*
0.913*
*p Value 5 0.05.
significantly by race 0, = 0.008).The occurrencewashigher amongblacks. No significant difference wasnoted for gender. None of the health factors listed in Table III were found to be significantly associatedwith the occurrenceof metallic taste. Of the oral hygiene factors and the dental factors listed in Tables V and VI, four were significantly related to metallic taste. Patients who reported sensitivity to heat and cold (p = 0.016) were more likely to report the presenceof a metallic taste than those who were not experiencing such sensitivity. Also, thosepatients who reported that they noticed they were grinding their teeth (p = 0.006) and patients with bruxism (p = 0.007) were more likely tc report tasting a metallic flavor than thosewho did not have these oral habits.
126
As the number of fixed partial dentures increased,the occurrenceof metallic taste alsoincreased(p = 0.001).Patients with crowns reported tasting a metallic flavor 7.4% of the time (Table VI). Those with one fixed partial denture and crownsreported tasting a metallic flavor 14.2% of the time and patients with two fixed partial dentures, 20.5% of the time.
DISCUSSION This analysis revealed that the occurrenceof a metallic taste decreasedwith age. This age-relatedtrend may be a result of a general diminution in taste that often occurs with aging.2*4*5*gvla Why more blacks than whites report tasting a metallic flavor cannot be explained and warrants further research.
FEBRUARY
1990
VOLUME
63
NUMBER
2
VA PROJECT
Table
V.
147:
METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Oral hygiene factors investigated in occurrence of metallic taste Factor
Oral
hygiene
factors
No. of patients
Tooth pain or soreness Tooth sensitivity to heat and cold Tooth sensitivity to sweets Presence of jaw pain Presence of sore gingivae Presence of “mout.h sores” Bruxism Presence of “trench mouth” Difficulty in chewing Difficulty in swallowing Presence of loose teeth Regular dental care Regular dental cletiining History of “gum treatment” Consumption of “sweets” Toothbrushing Use of dental floss Grinds teeth
present
Factor
Metallic
55 177 78 19 32 40 125 17 29 17 21 542 518 86 455 600 432 109
taste
%
No. of patients
14.6 16.4 15.4 21.1 12.5 7.5 18.4 17.7 17.2 25.5 9.5 11.3 11.2 5.8 10.8 11.3 11.1 19.3
8 29
12 4 4 3 23 3 5 4 2 61 58 5 49 68 48 21
not present Metallic
taste
60 39 56 64 64 65 45 65 63 64 66 7 10 63 19 0 20 47
549
426 526 585 572 564 479 587 575 586 583 61 85 517 149 4 172 493
%
p Value
0.558 0.016* 0.297 0.316 1.000 0.603 0.007* 0.648 0.457 0.218 1.000 1.000 1.000 0.122 0.606 1.000 0.969 0.006*
10.9 9.2
10.7 10.9 11.2 11.5 9.4 11.1 11.0 11.0 11.3 11.5 11.8 12.2 12.8 0.0 11.6 9.5
*p Value 5 0.05.
Table
VI.
Dental factors investigated in occurrenceof metallic taste Factor Dental
factors
No. of patients
Type of restorations Crown-crown Crown-fixed partial denture Fixed partial denture-fixed partial denture
present Metallic
taste
%
p Value
0.001* 338 183 83
25 26 17
7.4 14.2 20.5
*p Value c 0.05.
Table
VII.
Reports of metallic taste at visit Visit
Test alloy
Ticon Ceramalloy II Micro-Bond NP2 W-l Total
(months
after
JOURNAL
OF PROSTHETIC
of restoration)
1
6
12
24
36
48
7/138 9/136 51137 3/145 241556
9/126 8/131 5/134 8/131 301522
3/112 51124 6/121 6/121 20/478
5/69 2/73 4/78 7/73 181293
2/37 o/34 3/34 2/32 7/137
117 l/9 o/10 o/11 2/37
Theseanalysesalso revealedthat patients who reported sensitivity to heat and cold were alsomore likely to report the occurrenceof metallic taste. This may be becauseof a lessthan ideal dentition, asindicated by the symptomsof sensitivity. These personsmay possibly represent a group that hasunexplained generalizedheightenedoral sensitivity. The associationof metallic taste with type of restoration
THE
placement
DENTISTRY
Total
271489 25/507 23/514 26/513 101/2023
(5.5%) (4.9 % ) (4.5%) (5.1%) (5.0% )
was not surprising. The occurrence of metallic taste was greater in patients who had fixed partial dentures than in patients with crowns. Reports of tasting a metallic flavor increasedin patients as the number of their fixed partial dentures increased.These occurrencesmay be a result of an increasedamount of metal or dissimilar metals in the mouth. The occurrenceof metallic taste wasstrongly associated
127
MORRIS
with bruxism and grinding. Studies have shown that dental alloys release ions in saliva at a significant rate.ls* 2oThe increased abrasion found in patients with bruxism may raise the level of ions to a level of perception in patients who tend to have this habit. There were no significant associations between metallic taste and any of the other factors studied. Although not associated with metallic taste in this report, it is possible that other factors, such as oral hygiene, use of tobacco, and alcohol consumption, may be associated with other forms of dysgeusia not examined in this study. For any given visit, about 5% of the patients reported tasting a metallic flavor regardless of which test alloy was used in their dental restoration (Table VII). Most of the patients (63 of 101) could not determine which restoration (the control or the test alloy) was causing the metallic taste. When they could tell, they were as likely to choose the control(20 of 101) as the test alloy (18 of 101). Of the 68 persons who reported tasting a metallic flavor, only two requested that the restorations be removed. Alterations in the sense of taste can have broad effects on a patient’s well-being. Because the mouth plays a major role in taste perception, any changes in the sense of taste should be investigated for possible dental or medical factom.
CONCLUSIONS As a result of our study, we offer the following conclusions: 1. The occurrence of metallic taste is significantly but inversely associated with age. 2. Blacks report the presence of metallic taste more frequently than whites. 3. Patients with fixed partial dentures are more likely to report the presence of metallic taste than patients with crowns. 4. Bruxism is associated with metallic taste. 5. Persons reporting sensitivity to heat or cold are more likely to report the occurrence of metallic taste. 6. Metallic taste is reported in 5% of all evaluations. 7. Of patients who reported tasting a metallic flavor, most could not identify the source. 8. When the source of the metallic taste can be identified, the control alloy that contained gold is chosen as often as the alternative alIoy that doesnot contain gold. 9. Metallic taste does not appear to be a significant problem with the use of alternative alloys. REFERENCES 1. U.S. Public Health Service. Report of the Panel on Communicative Diirders to the National Advisory Neurological and Communicative Disorders and Stroke Council. Washington, DC: National Institutes of Health, 1979; NIH publication no. 79-1914:319. 2. Schiffman SS. Taste and smell in disease. Part 1. N Engl J Med 1983;308:1276-9. 3. Aker F. The role of taste and taste dysfunction in oral diagnosis. Quintesaence International 1980;11:81-9.
128
ET AL
4. Schiffman SS. Taste and smell in disease. Part 2. N Engl J Med 1983;308:1337-43. 5. Ramsey WO. Nutritional problems of the aged. J PROSTHET DENT 1983:49:16-g. 6. Hardy SL, Brennand CP, Wyse BW. Taste thresholds of individuals with diabetes mellitus and of control subjects. J Am Diet Assoc 1981;79:286-9. 7. McConnell RJ, Menendez CE, Smith FR, Henkin RI, Rivlin RS. Defecta of taste and smell in patients with hypothyroidism. Am J Med 1975;59:354-64. 8. Carson JS, Gormican A. Disease-medication relationships in altered taste sensitivity. J Am Diet Asaoc 1976;68:550-3. 9. Bradley RM. Basic oral physiology. Chicago: Year Book Medical Publishers, Inc, 1981:21-42. 10. Bull TR. Taste and the chorda tympani. J Laryngology and Otology 1965;79:479-93. 11. Axe11 T, Nilner K, Nilsson B. Clinical evaluation of patienta referred with symptoms related to oral galvanism. Swed Dent J 1983,7:169-78. 12. Craig RC, O’Brien WJ, Powers JM. Dental materials: properties and manipulation. 2nd ed. St Louis: CV Mosby, 197912. 13. Hyde RJ, Feller RP, Sharon IM. Tongue brushing, dentifrice, and age effects on taste and smell. J Dent Res 1981;60:1730-4. 14. Langan MJ. Yearick ES. The effects of improved oral hygiene on taste perception and nutrition of the elderly. J Gerontol 1976;31:413-8. 15. Coats AC. Effects of age, sex, and smoking on electrical taste threshold. Ann Otol 1974$X%365-9. 16. Henkin RI, Schechter PJ. Hoye R, Mattern CFT. Idiopathic hypogeusia with dysgeusia, hyposmia, and dysosmia: a new syndrome. JAMA 1971;217:434-40. 17. Morris HF. A multidisciplinary multicenter experimental design for the evaluation of alternative metal-ceramic alloys. Veterans Administration Cooperative Studies Project No. 147, Part 1. J PROSTHET DENT 1986;56:402-6. 18. Corso JF. Sensory processes and age effects in normal adults. J Ceronto1 1971;26:90-105. 19. Newman S. Chamberlain RT, Nunez LJ. Nickel solubility from nickelchromium dental casting alloys. J Biomed Mater Rea 1981:15:615-7. 20. Covington JS, McBride MA, Slagle WF, Disney AL. Quantization of nickel and beryllium leakage from base metal casting alloys. J PRO~~HET DENT 1985;54:127-36. Reprint requests to: DR. HAROLD F. MORRIS VA MEDICAL CENTER 2215 FULLER RD. ANN ARBOR, MI 48105
(154)
ADDENDUM Authors: Dennis Weir, D.D.S., M.A., VeteransAdministration (VA) MedicalCenter,andAssociate ClinicalProfessor, University of California,San Francisco School of Dentistry, San Francisco, Calif.; James Lockwood, D.D.S., Research Assistant, VA Medical Center, Ann Arbor, Mich.; Susan Szpunar, MPH, DrPH, Research Assistant, VA Medical Center, Ann Arbor, Mich.; Alan Cantor, Ph.D., Study Biostatistician, VA Hospital, Hines, 111.;Warren &offer, D.M.D., VA Medical Center, and Clinical Associate Profeasor, University of Pittsburgh School of Dental Medicine, Pittsburgh, Pa.; David Irvin, D.D.S., VA Medical Center, San Diego, Calif.; Adele Gray, D.D.S., Research Assistant, VA Medical Center, Ann Arbor, Mich.; Roland Mais, M.S., Health Research Scientist, VA Biostatistician,
Medical Center, Hines, Ill.; Linda VA Medical Center, Hines, Ill.
Sabella,
MS.,
Coauthors: James Pikulski, D.D.S.; John Blankenship, D.D.S., M.S.; Thomas Stein, D.M.D., M.S.; Gregory Movsesian, D.D.S.; Frank Lauciello, D.D.S.; John Mozrall, D.D.S.; Roger Cwynar, D.M.D.; Stephen Schlimmer, D.D.S.; Richard Navarro, D.D.S., M.S.; Raul Cafl’esse, D.D.S., M.S.; Robert Lorey, D.D.S., M.S.; Richard McPhee, D.D.S., MS.; Sheldon Winkler, D.D.S. Executive Committee: Harold F. Morris, D.D.S., MS., Chairman; Alan Cantor, Ph.D; Dennis Weir, D.D.S., M.A.; David
FEBRUARY
1!9@ll
VOLUME
69
NUMBER
2
VA PROJECT
147: METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Irvin, D.D.S.; Warren Stoffer, D.M.D.; Alan Helisek; Richard McPhee, D.D.S., M.S.; Raul Caffesse, D.D.S., M.S. Data Monitoring Board: Gunnar Ryge, D.D.S., M.S., Chairman; Marjorie Swartz, B.S., M.S.; Bart Hsi, Ph.D.; William Gillette, D.D.S.; Joseph Moffa, D.D.S., M.S. Statistical Support Center: William Henderson, Ph.D.; Alan Cantor, Ph.D.; Roland Mais, M.S.; Barbara Christine; Ann Horney; Jean Rowe; Linda Sabella, M.S. Chairman’s Office: Harold F. Morris, D.D.S., M.S.; Patricia M. Zawadzki, R.D.H., M.S.; Peggy A. Piech; Beverly Barnes. Clinical Research Assistants: Kari Gregerson; Mary Pet-
rie; Nancy Bernat; Mary Ann Steffensmeier; Greer Collins; Anne Cade. Cooperative Studies Program Central Administration: Daniel Deykin, M.D., Chief; Janet Gold, Administrative Officer; Ping Huang, Ph.D., Staff Assistant. Hines VA Cooperative Studies Program Coordinating Center Human Rights Committee: Eileen Hagarty, R.N., M.S., Chairperson; Walter Dorus, M.D.; Nicolas Emanuele, M.D.; Donna Franklin, Ph.D.; Robert Lee; Thomas Schmid, Ph.D.; Rev. Jeffrey Stinehelfer; Kenneth Young; Martin Feldbush, D. Min.
Pulp response to a composite resin with and without a surface seal Anna B. Fuks, C.D.,* Barry Funnell, B.D.S.(Rand.),** Peter Cleat,on-Jones, B.D.S., M.B.B.Ch., Ph.D.***
inserted
in deep cavities
and
Hebrew University-Hadassah School of Dental Medicine, Jerusalem, Israel, and University of the Witwatersrand, Dental Research Institute, Johannesburg, South Africa The objective of the present investigation was to observe pulp response to a composite material (Occlusin) placed in deep cavities with and without a zinc oxide-eugenol covering. Deep cavities were prepared in 116 teeth of four young baboons and divided into four groups. In group 1, Occlusin material was placed directly into the cavity, without etching, to approximately half the depth, cured, and covered to the surface with zinc oxide-eugenol. In group 2, the cavities were etched, a bonding agent was applied, and Occlusin material was used and cured in two increments to fill the cavities up to the surface. In group 3, the composite resin was placed in two increments as in group 2, but without etching and bonding; and in group 4 (control), the cavities were filled up to the surface with zinc oxideeugenol. Follow-up times were 6,30, and 90 days, Light microscopy revealed that, although some differences were observed, a good pulp response was evident in all groups.(J PROSTAET D~~~1990;63:129-34.)
N
umerousstudies have demonstrated the toxicity of dental restorative materials, imputing adversepulp responsesto someof their constituents.l-10Other reports implicate bacterial penetration as the main causeof pulp inflammation under restorations as a result of marginal microleakage.11-17 A major causeof microleakage is poor adaptation of restorative materials to tooth structure, possibly becauseof inferior adaptability of the material or faulty insertion.r8Another causeof leakageis shrinkageof the material resulting from chemical or physical changes after insertion.18
*Associate Professor, Department of Pedodontics, Hebrew University-Hadassah School of Dental Medicine. **Research Associate, University of the Witwatersrand, Dental Research Institute. ***Professor and Director, University of the Witwatersrand, Dental Research Inst.itute. 10/l/16842
THE
JOURNAL
OF PROSTEETIC
DENTISTRY
Table
I. Distribution of treated teeth Types
Treatment
groups
Permanent
and
number
of teeth
Primary
1
20
2
18
3
12
4
10
18 18 12 8
60
56
Total
Totai 38 36 24
18 116
Grosset al.lg reported, in an in vitro study, that Scotchbond material effectively inhibited microleakageat the occlusal portion of class II restorations when applied to etched enamel. Later, in a summarizing review on microleakage, RetiefZOconcludedthat acid etching of enamelcan effectively eliminate microleakageof compositeresin restorations, provided that sufficient enamelis present, particularly at the gingival aspectsof the restorations.
129
of CSP Nos.
147/242*
and Harold
F. Morris,
D.D.S.,
No. alloys
M.S.**
VeteransAdministrationMedicalCenter,Ann Arbor, Mich. We examined patients to find out whether they noticed the prevalence of metallic taste and set out to determine the association of metallic taste with demographic, medical, and dental factors. Data were collected as part of a Veterans Administration Cooperative Study investigating the suitability of alternative metal ceramic alloys as substitutes for alloys that contain gold. Crowns and fixed partial dentures were made from control and alternative alloys for accepted volunteer patients. A month after placement of the restorations and at regularly scheduled recall appointments, the patients were asked if they tasted a metallic flavor. Of the 2023 times the question was asked, 101 positive responses were given by 68 patients (46 reported metallic flavor once, and 22 reported it more than once). Results indicated that youth, sensitivity to heat and cold, bruxism, grinding, and an increasing number of restorative units were significantly related to metallic taste. For any given visit, about 5% of the patients reported tasting a metallic flavor regardless of the type of alloy that was used in the restoration. Metallic taste does not appear to be a problem with alternative alloys. (J PROSTHET DENT 1990;63:124-9.)
T
he mouth has a sophisticated arrangement of sensorimotorsystemsthat regulatemastication, salivation, swallowing,and speaking. Primarily a feeding apparatus, the mouth dependson the senseof taste to evaluate foods. A distorted senseof taste (dysgeusia)or a diminishedsense of taste (hypogeusia) can detract significantly from these functions. Approximately two million American adults have disordersof the sensesof taste and of smell.l Despite their prevalence, these disorders have largely been neglected by the medical community becausethe disorders are not fatal and are not considered serious handicaps. However, disordersof the senseof taste can present major problems,becausedietary habits, digestion,nutrition, and the palatability of food can all be affected. In severecases, disordersof the senseof taste can be highly disruptive and can causestress,anorexia, and depression.2 Several factors have been implicated in the etiology of dysgeusia.For example,the following factors are known to affect the sensesof both taste and smell:various endocrine disorders,cancer,nutritional deficiencies,radiation, aging, trauma, restorative dentistry, hygienic factors related to infected gingivae and teeth, craniofacial abnormalities,
Supportedby the VeteransAdministrationMedical Research Service/Cooperative StudiesProgramand the NationalInstitute of Dental Research,InteragencyContract No. lYOlDE-50004-00, and conductedby the VeteransAdministration CSPNos.147/242,DentalResearchGroup. *Completeauthorshipappearson last pageof article. **Study ChairmenandDirector,ClinicalResearch Centerfor RestorativeMaterials,Veterans AdministrationMedical Center; ClinicalAssociateProfessor,Universityof Michigan,School.of Dentistry,Ann Arbor, Mich. 10/l/16021
124
psychiatric disorders,and severalmedications.2-g Deficiencies in the sense of smell (dysosmia, hyposmia, and anosmia)can contribute to deficienciesin the senseof taste and in differentiation of flavor.2pg Metallic taste may specifically be causedin part by medications, especiallymedications used by the elderly.5 Metallic taste may alsoarise as a result of trauma to the chorda tympani nerve, which could be injured during various surgicalprocedures5ylo In addition, dental galvanism,the production of an electrical current between two dissimilar metals,is reported to lead to sensationsof metallic taste.l’ A common example of dental galvanismis the contact between a piece of aluminum foil and an amalgamrestoration.12 Studies of the associationof age and the senseof taste have yielded contradictory results. Ramsey5reported that the lossof taste buds with age is progressiveand continuous, whereasBradley9 reports a nearly constant level of taste buds until about the ageof 75, when the number decreasessignificantly. Bamsey5cited a resulting lossin the differentiation of flavor, whereasBradleys claims there is no evidence supporting a causalrelationship between loss of taste buds and decreasedtaste sensitivity. The role of oral hygiene in taste disordershas alsobeen reported. Hyde et a1.13 found that thorough tongue brushing generally increasedtaste thresholds in older adults. Langan and Yearick’* reported an improved senseof taste in an experimental group of elderly adults undergoingprofessionaloral hygiene therapy. Little researchhasbeenconducted on the associationof the useof tobacco or alcoholand altered sensationof taste. One study found that, with aging, smoking caused a progressivedeterioration in the taste threshold of men, but not of women.15 Finally, Henkin et a1.16have reported on a syndrome of
FEBRUARY1990 VOLUME63
NUMBER2
VA PROJECT
Table
I.
147:
METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Study alloys
II. Approximate alloys (weight 7%)
Table
Alloy
Manufacturer
chemical compositions Test
Test alloys Ceramalloy
11
Johnson & Johnson Dental Products Co. IL Windsor, N.J. Ticonium Co. Albany, N.Y. Austenal Dental, Inc., A Nobelpharma Co. Chicago, Ill. Williams Dental Co., Inc. Buffalo, N.Y.
Ticon Micro-Rand
NP2
W-l Control alloy Olympia
J.F. Jelenko & Co. Armonk, N.Y.
hypogeusia with dysgeusia, hyposmia, and dysosmia. Patients having this syndrome frequently report a bizarre history and display no objective signs, which have led many physicians to suggest psychiatric causes rather than gustatory or olfactory causes. Reported symptoms include tasting a perpetual sweet, sour, salty, bitter, or metallic flavor, as well as smelling a persistent foul odor. Patients have also reported vertigo, hearing loss, and unexplained hypertension. Because the cause of taste disorders is not well understood and often involves the interplay of a variety of factors, there are few established interventions for this condition. Persons with taste disorders can often achieve temporary relief by chewing gum or ice, rinsing with sodium bicarbonate or long-lasting sweeteners, or applying local anesthetics. Dietary supplementation with zinc sulfate has been found to be an effective treatment in some patients47 g,ltj In this study, we investigated the prevalence of one form of dysgeusia-metallic taste-and its association with several demographic, medical, and dental/oral variables in a patient population.
MATERIAL
AND
METHODS
The data for this analysis were collected as part of a Veterans Administ,ration Cooperative Study that was investigating the suitability of alternative alloys as substitutes for alloys containing gold that are used for fixed prosthodontic restorations. Volunteers were accepted into the clinical study if they required complete crowns, fixed partial dentures, or both and if they met a series of dental and medical eligibility criteria.i7 When patients accepted into the study required more than two restorations, a determination was made as to which two restorations would be included in the analyses. The additional restorations needed were inserted but were not included in the study comparisons. This allowed
TEE
JOURNAL
OF
PROSTHETIC
DENTISTRY
Elements Au Pd Ag In Ga Sn Ni Cr Be Si Mn MO B Al Fe
alloy
of study
Control
Ceramalloy II
Ticon
Micro-Bond NP2
0 0 0 0 0 0 71.5 19.0 0 4.0 0 4.5 0.5 0 0
0 0 0 0 0 0 71.0 17.0 1.0 0 3.0 4.0 0.5 3.5 0
0 0 0 0 7.5 0 66.0 13.5 0 0.8 0 7.0 0 0 5.0
W-l 0 53.5 37.5 0.5 0 8.5 0 0 0 0 0 0 0 0 0
alloy
Olympia 51.5 38.5 0 8.5 1.5 0 0 0 0 0 0 0 0 0 0
paired comparisons between the alloy containing gold (control) and the alternative (test) alloy. Within each pair of restorations, the assignment of control or test alloy was randomly made. The particular alternative alloy used was also assigned in a random fashion. Lists of the alloys studied and their approximate chemical compositions are provided in Tables I and II. One month after placement of the restorations, patients were observed, and baseline measurements were recorded. Patients were recalled at 6-month intervals for maintenance visits and at l-year intervals for evaluation of the restorations. At recall visits, patients were asked whether they tasted the presence of a metallic flavor and other pertinent questions. A total of 604 patients from VA hospitals in six cities were questioned for this study. Unless indicated, all analyses were carried out with the use of the chi-square test. Tables III and IV list the health factors and the demographic factors that were included in this investigation. Tables V and VI list the oral hygiene factors and the dental factors included in the analysis. These tables include the percentage of patients who tasted a metallic flavor.
RESULTS The question about metallic taste was asked 2023 times, and 68 patients gave 101 positive responses. Forty-six of the patients reported they tasted a metallic flavor once, while 22 patients reported tasting a metallic flavor more than once. Of the demographic variables evaluated, the prevalence of metallic taste was significantly, but inversely, related to age. Patients 30 years of age and younger reported metallic taste more often than those older than 30 0, = 0.025). The prevalence of metallic taste differed
125
MORRIS
Table
Health factors investigated in occurrence of metallic taste
III.
Factor
Health
factors
Use of penicillin or sulfonamides Use of anticoagulant drugs Use of cortisone drugs Use of tranquilizers Current medication Recent (last 1 - 2 months) medication Presence of liver disease Presence of “acid stomach” Presence of hiatal hernia Presence of ulcers Presence of “nervous condition” Presence of kidney disease Need for frequent urination Excessive thirst Presence of diabetes Recent change in health Presence of hives Presence of allergies Presence of hypertension Use of cigarettes Use of alcohol Table
ET AL
No. of patients
present Metallic taste
460 30 67 201
4 114 50 51 66 20 56 42 15 44 146 127 86 278 430
w
55
12.0 3.3 7.5 9.0 10.4 9.6 0.0 12.3 12.0 7.8 10.6 4.4 10.7 2.4 6.7
1 5 18 20 17 0 14 6 4 7 3 6
192 177
Factor
1 1
15 7 39 51
No. of patients
Metallic taste
144
13 67 63 50 45 51 68 54 62 64 61 65 62 67 67 64 47 53 61 29 17
574 537 401
397 424 600
490 553 553 537 584 548 561
589
9.1 14.4 11.8 8.1 14.0 11.9
4 21
not present
560 458 467 518 326 172
%
p Value
9.0 11.7
0.413 0.266 0.402 0.251 0.847 0.475
11.7 12.5 11.3 12.0 11.3 11.0 11.2 11.6 11.4 11.1 11.3 11.9 11.4 11.4 10.3 11.4 11.8 8.9 9.9
1.000 0.827
1.000 0.565
1.000 0.858
1.000 0.102 0.876 0.822 0.222
1.000 0.421 0.063 0.583
Demographic factors investigated in occurrence of metallic taste
IV.
Factor Demographic
factors
No. of patients
present Metallic
taste
96
p Value
Age (~4 >30 530
Race White Black Gender Male Female
0.025* 330 274
28 40
8.5 14.6
471 106
45 21
9.6
19.8
544 60
62 6
11.4 10.0
0.008*
0.913*
*p Value 5 0.05.
significantly by race 0, = 0.008).The occurrencewashigher amongblacks. No significant difference wasnoted for gender. None of the health factors listed in Table III were found to be significantly associatedwith the occurrenceof metallic taste. Of the oral hygiene factors and the dental factors listed in Tables V and VI, four were significantly related to metallic taste. Patients who reported sensitivity to heat and cold (p = 0.016) were more likely to report the presenceof a metallic taste than those who were not experiencing such sensitivity. Also, thosepatients who reported that they noticed they were grinding their teeth (p = 0.006) and patients with bruxism (p = 0.007) were more likely tc report tasting a metallic flavor than thosewho did not have these oral habits.
126
As the number of fixed partial dentures increased,the occurrenceof metallic taste alsoincreased(p = 0.001).Patients with crowns reported tasting a metallic flavor 7.4% of the time (Table VI). Those with one fixed partial denture and crownsreported tasting a metallic flavor 14.2% of the time and patients with two fixed partial dentures, 20.5% of the time.
DISCUSSION This analysis revealed that the occurrenceof a metallic taste decreasedwith age. This age-relatedtrend may be a result of a general diminution in taste that often occurs with aging.2*4*5*gvla Why more blacks than whites report tasting a metallic flavor cannot be explained and warrants further research.
FEBRUARY
1990
VOLUME
63
NUMBER
2
VA PROJECT
Table
V.
147:
METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Oral hygiene factors investigated in occurrence of metallic taste Factor
Oral
hygiene
factors
No. of patients
Tooth pain or soreness Tooth sensitivity to heat and cold Tooth sensitivity to sweets Presence of jaw pain Presence of sore gingivae Presence of “mout.h sores” Bruxism Presence of “trench mouth” Difficulty in chewing Difficulty in swallowing Presence of loose teeth Regular dental care Regular dental cletiining History of “gum treatment” Consumption of “sweets” Toothbrushing Use of dental floss Grinds teeth
present
Factor
Metallic
55 177 78 19 32 40 125 17 29 17 21 542 518 86 455 600 432 109
taste
%
No. of patients
14.6 16.4 15.4 21.1 12.5 7.5 18.4 17.7 17.2 25.5 9.5 11.3 11.2 5.8 10.8 11.3 11.1 19.3
8 29
12 4 4 3 23 3 5 4 2 61 58 5 49 68 48 21
not present Metallic
taste
60 39 56 64 64 65 45 65 63 64 66 7 10 63 19 0 20 47
549
426 526 585 572 564 479 587 575 586 583 61 85 517 149 4 172 493
%
p Value
0.558 0.016* 0.297 0.316 1.000 0.603 0.007* 0.648 0.457 0.218 1.000 1.000 1.000 0.122 0.606 1.000 0.969 0.006*
10.9 9.2
10.7 10.9 11.2 11.5 9.4 11.1 11.0 11.0 11.3 11.5 11.8 12.2 12.8 0.0 11.6 9.5
*p Value 5 0.05.
Table
VI.
Dental factors investigated in occurrenceof metallic taste Factor Dental
factors
No. of patients
Type of restorations Crown-crown Crown-fixed partial denture Fixed partial denture-fixed partial denture
present Metallic
taste
%
p Value
0.001* 338 183 83
25 26 17
7.4 14.2 20.5
*p Value c 0.05.
Table
VII.
Reports of metallic taste at visit Visit
Test alloy
Ticon Ceramalloy II Micro-Bond NP2 W-l Total
(months
after
JOURNAL
OF PROSTHETIC
of restoration)
1
6
12
24
36
48
7/138 9/136 51137 3/145 241556
9/126 8/131 5/134 8/131 301522
3/112 51124 6/121 6/121 20/478
5/69 2/73 4/78 7/73 181293
2/37 o/34 3/34 2/32 7/137
117 l/9 o/10 o/11 2/37
Theseanalysesalso revealedthat patients who reported sensitivity to heat and cold were alsomore likely to report the occurrenceof metallic taste. This may be becauseof a lessthan ideal dentition, asindicated by the symptomsof sensitivity. These personsmay possibly represent a group that hasunexplained generalizedheightenedoral sensitivity. The associationof metallic taste with type of restoration
THE
placement
DENTISTRY
Total
271489 25/507 23/514 26/513 101/2023
(5.5%) (4.9 % ) (4.5%) (5.1%) (5.0% )
was not surprising. The occurrence of metallic taste was greater in patients who had fixed partial dentures than in patients with crowns. Reports of tasting a metallic flavor increasedin patients as the number of their fixed partial dentures increased.These occurrencesmay be a result of an increasedamount of metal or dissimilar metals in the mouth. The occurrenceof metallic taste wasstrongly associated
127
MORRIS
with bruxism and grinding. Studies have shown that dental alloys release ions in saliva at a significant rate.ls* 2oThe increased abrasion found in patients with bruxism may raise the level of ions to a level of perception in patients who tend to have this habit. There were no significant associations between metallic taste and any of the other factors studied. Although not associated with metallic taste in this report, it is possible that other factors, such as oral hygiene, use of tobacco, and alcohol consumption, may be associated with other forms of dysgeusia not examined in this study. For any given visit, about 5% of the patients reported tasting a metallic flavor regardless of which test alloy was used in their dental restoration (Table VII). Most of the patients (63 of 101) could not determine which restoration (the control or the test alloy) was causing the metallic taste. When they could tell, they were as likely to choose the control(20 of 101) as the test alloy (18 of 101). Of the 68 persons who reported tasting a metallic flavor, only two requested that the restorations be removed. Alterations in the sense of taste can have broad effects on a patient’s well-being. Because the mouth plays a major role in taste perception, any changes in the sense of taste should be investigated for possible dental or medical factom.
CONCLUSIONS As a result of our study, we offer the following conclusions: 1. The occurrence of metallic taste is significantly but inversely associated with age. 2. Blacks report the presence of metallic taste more frequently than whites. 3. Patients with fixed partial dentures are more likely to report the presence of metallic taste than patients with crowns. 4. Bruxism is associated with metallic taste. 5. Persons reporting sensitivity to heat or cold are more likely to report the occurrence of metallic taste. 6. Metallic taste is reported in 5% of all evaluations. 7. Of patients who reported tasting a metallic flavor, most could not identify the source. 8. When the source of the metallic taste can be identified, the control alloy that contained gold is chosen as often as the alternative alIoy that doesnot contain gold. 9. Metallic taste does not appear to be a significant problem with the use of alternative alloys. REFERENCES 1. U.S. Public Health Service. Report of the Panel on Communicative Diirders to the National Advisory Neurological and Communicative Disorders and Stroke Council. Washington, DC: National Institutes of Health, 1979; NIH publication no. 79-1914:319. 2. Schiffman SS. Taste and smell in disease. Part 1. N Engl J Med 1983;308:1276-9. 3. Aker F. The role of taste and taste dysfunction in oral diagnosis. Quintesaence International 1980;11:81-9.
128
ET AL
4. Schiffman SS. Taste and smell in disease. Part 2. N Engl J Med 1983;308:1337-43. 5. Ramsey WO. Nutritional problems of the aged. J PROSTHET DENT 1983:49:16-g. 6. Hardy SL, Brennand CP, Wyse BW. Taste thresholds of individuals with diabetes mellitus and of control subjects. J Am Diet Assoc 1981;79:286-9. 7. McConnell RJ, Menendez CE, Smith FR, Henkin RI, Rivlin RS. Defecta of taste and smell in patients with hypothyroidism. Am J Med 1975;59:354-64. 8. Carson JS, Gormican A. Disease-medication relationships in altered taste sensitivity. J Am Diet Asaoc 1976;68:550-3. 9. Bradley RM. Basic oral physiology. Chicago: Year Book Medical Publishers, Inc, 1981:21-42. 10. Bull TR. Taste and the chorda tympani. J Laryngology and Otology 1965;79:479-93. 11. Axe11 T, Nilner K, Nilsson B. Clinical evaluation of patienta referred with symptoms related to oral galvanism. Swed Dent J 1983,7:169-78. 12. Craig RC, O’Brien WJ, Powers JM. Dental materials: properties and manipulation. 2nd ed. St Louis: CV Mosby, 197912. 13. Hyde RJ, Feller RP, Sharon IM. Tongue brushing, dentifrice, and age effects on taste and smell. J Dent Res 1981;60:1730-4. 14. Langan MJ. Yearick ES. The effects of improved oral hygiene on taste perception and nutrition of the elderly. J Gerontol 1976;31:413-8. 15. Coats AC. Effects of age, sex, and smoking on electrical taste threshold. Ann Otol 1974$X%365-9. 16. Henkin RI, Schechter PJ. Hoye R, Mattern CFT. Idiopathic hypogeusia with dysgeusia, hyposmia, and dysosmia: a new syndrome. JAMA 1971;217:434-40. 17. Morris HF. A multidisciplinary multicenter experimental design for the evaluation of alternative metal-ceramic alloys. Veterans Administration Cooperative Studies Project No. 147, Part 1. J PROSTHET DENT 1986;56:402-6. 18. Corso JF. Sensory processes and age effects in normal adults. J Ceronto1 1971;26:90-105. 19. Newman S. Chamberlain RT, Nunez LJ. Nickel solubility from nickelchromium dental casting alloys. J Biomed Mater Rea 1981:15:615-7. 20. Covington JS, McBride MA, Slagle WF, Disney AL. Quantization of nickel and beryllium leakage from base metal casting alloys. J PRO~~HET DENT 1985;54:127-36. Reprint requests to: DR. HAROLD F. MORRIS VA MEDICAL CENTER 2215 FULLER RD. ANN ARBOR, MI 48105
(154)
ADDENDUM Authors: Dennis Weir, D.D.S., M.A., VeteransAdministration (VA) MedicalCenter,andAssociate ClinicalProfessor, University of California,San Francisco School of Dentistry, San Francisco, Calif.; James Lockwood, D.D.S., Research Assistant, VA Medical Center, Ann Arbor, Mich.; Susan Szpunar, MPH, DrPH, Research Assistant, VA Medical Center, Ann Arbor, Mich.; Alan Cantor, Ph.D., Study Biostatistician, VA Hospital, Hines, 111.;Warren &offer, D.M.D., VA Medical Center, and Clinical Associate Profeasor, University of Pittsburgh School of Dental Medicine, Pittsburgh, Pa.; David Irvin, D.D.S., VA Medical Center, San Diego, Calif.; Adele Gray, D.D.S., Research Assistant, VA Medical Center, Ann Arbor, Mich.; Roland Mais, M.S., Health Research Scientist, VA Biostatistician,
Medical Center, Hines, Ill.; Linda VA Medical Center, Hines, Ill.
Sabella,
MS.,
Coauthors: James Pikulski, D.D.S.; John Blankenship, D.D.S., M.S.; Thomas Stein, D.M.D., M.S.; Gregory Movsesian, D.D.S.; Frank Lauciello, D.D.S.; John Mozrall, D.D.S.; Roger Cwynar, D.M.D.; Stephen Schlimmer, D.D.S.; Richard Navarro, D.D.S., M.S.; Raul Cafl’esse, D.D.S., M.S.; Robert Lorey, D.D.S., M.S.; Richard McPhee, D.D.S., MS.; Sheldon Winkler, D.D.S. Executive Committee: Harold F. Morris, D.D.S., MS., Chairman; Alan Cantor, Ph.D; Dennis Weir, D.D.S., M.A.; David
FEBRUARY
1!9@ll
VOLUME
69
NUMBER
2
VA PROJECT
147: METALLIC
TASTE
IN METAL
CERAMIC
ALLOYS
Irvin, D.D.S.; Warren Stoffer, D.M.D.; Alan Helisek; Richard McPhee, D.D.S., M.S.; Raul Caffesse, D.D.S., M.S. Data Monitoring Board: Gunnar Ryge, D.D.S., M.S., Chairman; Marjorie Swartz, B.S., M.S.; Bart Hsi, Ph.D.; William Gillette, D.D.S.; Joseph Moffa, D.D.S., M.S. Statistical Support Center: William Henderson, Ph.D.; Alan Cantor, Ph.D.; Roland Mais, M.S.; Barbara Christine; Ann Horney; Jean Rowe; Linda Sabella, M.S. Chairman’s Office: Harold F. Morris, D.D.S., M.S.; Patricia M. Zawadzki, R.D.H., M.S.; Peggy A. Piech; Beverly Barnes. Clinical Research Assistants: Kari Gregerson; Mary Pet-
rie; Nancy Bernat; Mary Ann Steffensmeier; Greer Collins; Anne Cade. Cooperative Studies Program Central Administration: Daniel Deykin, M.D., Chief; Janet Gold, Administrative Officer; Ping Huang, Ph.D., Staff Assistant. Hines VA Cooperative Studies Program Coordinating Center Human Rights Committee: Eileen Hagarty, R.N., M.S., Chairperson; Walter Dorus, M.D.; Nicolas Emanuele, M.D.; Donna Franklin, Ph.D.; Robert Lee; Thomas Schmid, Ph.D.; Rev. Jeffrey Stinehelfer; Kenneth Young; Martin Feldbush, D. Min.
Pulp response to a composite resin with and without a surface seal Anna B. Fuks, C.D.,* Barry Funnell, B.D.S.(Rand.),** Peter Cleat,on-Jones, B.D.S., M.B.B.Ch., Ph.D.***
inserted
in deep cavities
and
Hebrew University-Hadassah School of Dental Medicine, Jerusalem, Israel, and University of the Witwatersrand, Dental Research Institute, Johannesburg, South Africa The objective of the present investigation was to observe pulp response to a composite material (Occlusin) placed in deep cavities with and without a zinc oxide-eugenol covering. Deep cavities were prepared in 116 teeth of four young baboons and divided into four groups. In group 1, Occlusin material was placed directly into the cavity, without etching, to approximately half the depth, cured, and covered to the surface with zinc oxide-eugenol. In group 2, the cavities were etched, a bonding agent was applied, and Occlusin material was used and cured in two increments to fill the cavities up to the surface. In group 3, the composite resin was placed in two increments as in group 2, but without etching and bonding; and in group 4 (control), the cavities were filled up to the surface with zinc oxideeugenol. Follow-up times were 6,30, and 90 days, Light microscopy revealed that, although some differences were observed, a good pulp response was evident in all groups.(J PROSTAET D~~~1990;63:129-34.)
N
umerousstudies have demonstrated the toxicity of dental restorative materials, imputing adversepulp responsesto someof their constituents.l-10Other reports implicate bacterial penetration as the main causeof pulp inflammation under restorations as a result of marginal microleakage.11-17 A major causeof microleakage is poor adaptation of restorative materials to tooth structure, possibly becauseof inferior adaptability of the material or faulty insertion.r8Another causeof leakageis shrinkageof the material resulting from chemical or physical changes after insertion.18
*Associate Professor, Department of Pedodontics, Hebrew University-Hadassah School of Dental Medicine. **Research Associate, University of the Witwatersrand, Dental Research Institute. ***Professor and Director, University of the Witwatersrand, Dental Research Inst.itute. 10/l/16842
THE
JOURNAL
OF PROSTEETIC
DENTISTRY
Table
I. Distribution of treated teeth Types
Treatment
groups
Permanent
and
number
of teeth
Primary
1
20
2
18
3
12
4
10
18 18 12 8
60
56
Total
Totai 38 36 24
18 116
Grosset al.lg reported, in an in vitro study, that Scotchbond material effectively inhibited microleakageat the occlusal portion of class II restorations when applied to etched enamel. Later, in a summarizing review on microleakage, RetiefZOconcludedthat acid etching of enamelcan effectively eliminate microleakageof compositeresin restorations, provided that sufficient enamelis present, particularly at the gingival aspectsof the restorations.
129
