Guld har i många år använts som rekonstruktionsmaterial vid bettrehabilitering. Mer än 50% av Sveriges vuxna befolkning har kronor och/eller broar framställda i guldlegering och guld används också till stift i rotfyllda tänder, på vilka sedan kronor kan fästas. Guld har länge betraktats vara inert, dvs. ej kunna ge några reaktioner vid användning i kroppen, men på senare år har en ökad frekvens av kontaktallergi mot guld kunnat konstateras. Kontaktallergi är en typ av allergi, som vid upprepad kontakt med ämnet kan ge patienten en reaktion i hud och slemhinna. När det gäller guld kan kontaktallergi uppstå t.ex. under guldringar, av örhänge eller av halsband. När man utreder patienter för kontaktallergi mot guld – s.k. lapptestning, fäster man en häfta med guldsaltet guldnatriumtiosulfat (GSTS) på ryggen i 48 timmar. Patienten tar efter dessa två dygn bort testlappen och 3–4 samt 7 dagar efter exponeringen värderas den eventuellt uppkomna reaktionen av en hudläkare. Reaktionerna kan klassas som ospecifika irritationsreaktioner, negativa reaktioner, tveksamma reak-tioner och allergiska (positiva) reaktioner av eksemtyp. 1991 började man i Malmö rutinmässigt använda GSTS vid lapptestning av kontaktallergi mot guld, och då kunde konstateras att 10 % av de testade uppvisade kontaktallergi mot guld. Man har också visat att ett positivt lapptest är en manifestation av kontaktallergi. GSTS är, efter nickelsulfat, det näst vanligaste allergenet, som ger positiv hudreaktion vid rutintestning av eksempatienter. Detta tillsammans med en enkätstudie, som indikerade att kontaktallergi för guld var överrepresenterat hos patienter som hade guld i munnen, utgör bakgrunden till detta avhandlingsprojekt. I det första delarbetet studerades om dentalt guld (kronor, broar, inlägg) kunde sättas i samband med kontaktallergi för guld. Patienterna som ingick i studien var patienter som skulle testas eftersom de hade eksem. Resultaten visade att de patienter som vid tandläkarundersökning visat sig ha guld i munnen också i större utsträckning hade kontaktallergi för guld vid lapptestning. Symtom i munnen eller tecken på munslemhinnereaktioner kunde dock inte sättas i samband med dentalt guld eller positivt lapptest för guld. Däremot kunde det konstateras att de som hade mycket guld i munnen i större utsträckning hade kontaktallergi mot guld. I delarbete två studerades guldhalten i blodet hos samma patientpopulation. Det kunde konstateras att de patienter som hade dentalt guld hade förhöjda värden av guld i blod. I tredje delarbetet undersöktes mängden guld i blod efter att patienterna fått guldinlägg, vilket motsvarar en krona men med en fyllnings utsträckning. Patienterna hade mer guld i blodet efter att inläggen satts in jämfört med mängden guld i blod innan inläggen sattes fast. Fortfarande 15 år efter att inläggen sattes in hade patienterna förhöjda värden av guld i blod, vilket måste tolkas som en kontinuerlig frisättning av guld från dentalt guld till blod. Förhöjda värden av guld i blod har visat sig ha betydelse för hudens reaktion i kontakt med guld. Huruvida det föreligger ett samband mellan dentalt guld, kontaktallergi mot guld och munslemhinnelesioner, är inte väl utrett. Dock har studier på patienter med oral lichen indikerat att dessa patienter skulle kunna vara allergiska mot guld, men även mot andra tandvårdsmaterial. I fjärde delarbetet undersöktes därför patienter med oral lichen, med avseende på kontaktallergi mot guld i jämförelse med kontrollpatienter, vilka var remitterade till Yrkes- och miljödermatologiska avdelningen, Hudkliniken i Malmö, för misstanke om allergiskt kontakteksem. I denna studie kunde man finna en numerär skillnad avseende kontaktallergi för guld men inte någon statistisk skillnad mellan grupperna. Det är därför av vikt att i fortsatta studier, med större undersökningsmaterial, försöka utröna om det finns ett statistiskt säkert samband mellan oral lichen och kontaktallergi mot guld eller andra tandvårdsmaterial eftersom dessa patienter kan uppleva perioder med stora besvär, vilka kan försvåra både födointag och upprätthållande av en adekvat munhygien.

Questionnaire studies have indicated that patients with dental gold will more frequently have contact allergy to gold. This study aimed at investigating the relationship between contact allergy to gold and the presence and amount of dental gold alloys. A total of 102 patients were referred for patch testing because of suspicion of contact allergy. Patch tests were performed with gold sodium thiosulphate 2% and 5%. The patients underwent an oral clinical and radiological examination. Contact allergy to gold was recorded in 30.4% of the patients, and of these 74.2% had dental gold (p=0.009). A significant correlation was found between the amount of gold surfaces and contact allergy to gold (p=0.008), but there was no statistical relationship to oral lesions. It is concluded that there is a positive relationship between contact allergy to gold and presence and amount of dental gold alloys.

The aim of the present controlled study was to investigate a possible relationship between contact allergies to potential allergens and oral lichen lesions. Eighty-three patients with oral lichen lesions (OLL) and control groups of age- and gender-matched dermatitis patients (DP, n = 83) and patch-tested dermatitis patients randomly selected from files (PSFF, n = 319) were included in the study. OLL and DP groups were patch-tested epicutaneously and examined intraorally. The frequencies of contact allergy to mercury and carvone were statistically higher in the OLL group than in the DP group. Surfaces of amalgam and composite restorations were statistically more frequent in the OLL group compared to the DP group. Contact allergy to nickel and colophony, the latter with a statistically significant difference, was more common in the DP group. The numerical difference found for nickel allergy was, however, not significant comparing the OLL and PSFF groups. Contact allergy to mercury was overrepresented in patients with OLL and has been reported in previous studies, but the present finding of an overrepresentation of contact allergy to carvone in patients with oral lichen lesions has not been reported previously. Carvone, in addition to mercury and gold, as previously suggested, can be one of the causative or maintenant factors for oral lichen lesions. Carvone-hypersensitive patients with oral lichen lesions should therefore avoid carvone-containing products for oral use.

The aetiology of oral lichen lesions is obscure. In this study the frequency of contact allergy to gold in 83 patients with oral lichen lesions was compared with that in two control groups, comprising 319 age- and gender-matched patients with dermatitis selected from files and 83 clinically examined dermatitis patients. All patients were tested epicutaneously with gold sodium thiosulphate. The two control groups tested were under examination for a tentative diagnosis of allergic dermatitis not related to oral problems. The frequency of contact allergy to gold was 28.9% in the patients with oral lichen lesions, 18.2% in patients selected from files, and 22.9% in the clinically examined control patients. The difference in frequency between patients with oral lichen lesions and those taken from files was statistically significant.

Establishing the clinical relevance of contact allergy to dental materials in patients with oral lichen lesions (OLL) may be difficult, and tests are often read only on day 3 or day 4; also, concentration of the tested allergens may vary. Several studies on dermatitis patients have shown that additional positive patch test reactions can be found after day 4. Therefore, the aim of the present study was to analyse the frequency of late positive reactions to potential allergens in patients with OLL. Eighty-three of 96 consecutive patients with biopsy-verified OLL were patch-tested with a recently developed lichen series. The patches were removed after 48 h and reactions read 3 and 7 days after application. A total of 129 contact allergies were found, and 26 (20.2 %) of the allergic reactions in 23 patients were seen on day 7 only. The 25.2 % increase in positive test reactions with an additional reading on day 7 in addition to day 3 was statistically significant. Metals were the substances with the highest frequency of late positive reactions. Patients with OLL cannot be considered properly investigated with regard to contact allergy, unless the testing has been performed with mandatory readings on day 3 (or day 4) and day 7. Late patch test readings are crucial in order to elucidate the role of contact allergy to dental materials in the aetiology of OLL.

OBJECTIVE: Several studies have reported increased levels of gold (Au) in the blood of patients with dental gold restorations. This study analyzed gold levels in blood plasma before dental gold inlay insertion, 0-12 months after, and 15 years after. MATERIAL AND METHODS: Plasma samples from 9 patients were taken before and 0-10 months after gold inlay insertion. Fifteen years after gold inlay insertion, further blood samples taken from 8 of these patients were analyzed for gold using inductively coupled plasma mass spectrometry. An oral examination was also carried out before and 15 years after gold inlay insertion. RESULTS: Gold levels in plasma were significantly higher 0-12 months after gold inlay insertion than before treatment (p=0.008). No significant difference in gold plasma levels was found between 0-12 months after and 15 years after insertion (p=0.109), although there was a significant correlation between the number of gold alloy surfaces and the amount of gold in plasma 15 years after insertion (p=0.028). CONCLUSIONS: This study supports a dose-related release of gold into plasma from dental gold restorations, a release that appears to be stable over time.

Previous studies have demonstrated an association between gold allergy and the presence of dental gold restorations. The aim of the present study was to investigate the relationship between the concentration of gold in blood (B-Au) and the number of tooth surfaces with gold alloys in subjects with and without contact allergy to gold. In 80 patients referred for patch testing because of eczematous disease, blood samples were taken and analyzed for B-Au using inductively coupled plasma mass spectrometry. The detection limit for the Au determination was 0.04 microg/L. In addition, a dentist made a clinical and radiological examination of the patients and registered the number of dental gold surfaces. Patients with dental gold restorations had a statistically significantly higher B-Au in Mann-Whitney U test (P = 0.025), (range < 0.04-1.07 microg/L) than patients without (range < 0.04-0.15 microg/L). Furthermore, a positive correlation was found between B-Au and the number of dental gold surfaces (P < 0.01). There was no statistically significant difference in B-Au between persons with and without contact allergy to gold. The study thus indicates that gold is released from dental restorations and taken tip into the circulation.

Purpose: To assess the clinical outcomes of maxillary overdentures supported by dental implants by conducting a literature review. Materials and Methods: An electronic search was undertaken in March 2019. Eligibility criteria included publications reporting cases of implant-supported maxillary overdentures with follow-up information. Results: A total of 131 publications were included (1,478 overdentures supported by 6,681 implants). The mean number of attachments per overdenture was 3.8 ± 1.2 (range: 1 to 9), and a bar-clip system was used in about half of the cases. The prostheses were followed up for a mean of 47.9 ± 32.8 (range: 1 to 240) months. A total of 401 implants (6.0%) failed in 219 patients (14.8%), and 55 prostheses (3.7%) failed at a mean of 40.2 ± 53.2 (range: 6 to 240) months after placement. Most of the failures happened within the first year after placement for both implants (52.1%) and prostheses (41.8%). Patients with fewer implants per prosthesis presented higher prosthesis failure rates than patients with more implants per prosthesis. The cumulative survival rate for dental implants after 19 years was 70.4%, and for implant-supported maxillary overdentures was 79.8%. Presence of palatal coverage and/or metallic structure/reinforcement does not seem to have an influence on failure rate. Of the most commonly used attachment systems, the ball/O-ring and the Ceka were the ones with the highest rates of patients having at least one implant failure. Conclusion: Most of the prosthesis failures were due to loss of implants, and the first year was the most critical period for failures. The number of dental implants placed per patient seemed to have an impact on the occurrence of overdenture failure.

BACKGROUND: The mint flavour carvone (l-carvone) is considered a weak contact allergen. However, contact allergy to carvone is more prevalent in patients with oral lichen planus or oral lichenoid lesions (OLP/OLL).

OBJECTIVE: Our aim was to investigate how carvone affects sensitized individuals through a use test with toothpaste containing carvone. Non-flavoured toothpaste served as control.

METHODS: Subjects were patch tested prior to the use test-14 subjects allergic to carvone (11 with OLP/OLL), 20 subjects with OLP/OLL and 3 healthy controls. The month-long use test comprised of using toothpaste twice daily. Subjects were examined fortnightly. Clinical signs were assessed with a mucosal scoring system. The subjects' oral health-related quality of life was measured with the oral health impact profile (OHIP-49).

RESULTS: Local reactions to the carvone toothpaste presented as aggravated OLL (7/10) and peri-oral eczema (2/10) in allergic subjects. They also had significantly higher mucosal and OHIP scores compared with those receiving non-flavoured toothpaste.

CONCLUSION: In sensitized individuals, oral exposure to carvone gives aggravated oral lesions and/or peri-oral eczema. The lesions mimic OLP and allergic individuals are therefore at risk of not being assessed with regard to flavour contact allergy.

A predominant part of the Swedish population uses toothpaste daily. Besides fluoride preventing caries, toothpastes usually have flavours added to make the user feel fresh and clean. Among potential allergens in toothpastes, flavours are the most common cause of oral or perioral lesions. Flavour concentrations vary between 0.3% and 2.0%, and usually several types of mint are used; however, the true composition of the added aroma is seldom known. l‐Carvone is a mint‐tasting flavour that can act as a potential allergen. Previous findings have shown that approximately 4% of a patch‐tested selected population in southern Sweden had a positive reaction to l‐carvone and half of them had oral inflammatory lesions, notably oral lichenoid lesions. Among patients with lichenoid lesions approximately 12% have a contact allergy to l‐carvone and several other contact allergies are more common in this patient group. The concentration of l‐carvone in toothpastes available for sale on the Swedish market was investigated. Sixty‐six different toothpastes were selected from local stores and pharmacies. l‐Carvone content was extracted from toothpastes using n‐heptane. The sample extracts were separated on a silica column using straight‐phase high‐performance liquid chromatography and a diode‐array detector. Three samples of each toothpaste were analysed, and the mean concentration and relative SD were calculated. Detectable levels of l‐carvone (0.00005–0.35%) were found in 63 of the toothpastes. l‐Carvone was found in half of the toothpastes (n = 32) at a concentration of ≥ 0.01%. A higher concentration (≥ 0.1%) was found in 18% (n = 12). Of the top six toothpastes with highest l‐carvone content (0.15–0.35%), one was intended for use by children. Two of the toothpastes were stated as having fruit flavour, but there were still detectable levels of l‐carvone (0.0003% and 0.00007%, respectively). l‐Carvone was below detectable levels in three of the toothpastes, where one was stated as being without flavour. l‐Carvone is present in virtually all toothpastes on the Swedish market. It is therefore likely that l‐carvone in toothpastes is important for the induction of sensitization to l‐carvone, as contact allergy to l‐carvone is over‐represented in patch‐tested individuals with oral lichenoid reactions. However, are the concentrations demonstrated relevant for causing reactions or aggravating already existing lesions?

Carvone (l-carvone), a mint flavour in spearmint oil, is considered a mild skin sensitizer. Carvone-sensitization may be linked to oral/perioral signs and oral lichen planus, but studies are sparse. The prevalence of patch test reactions to carvone and relevant findings from the positive group were investigated. Records for patch-tested patients at the Malmö clinic, for the period 1996 to 2016, were studied. Carvone-positive and carvone-negative patients were compared regarding patch test data from baseline series and dental series. Dental series-tested carvone-positive patients were also compared with a matched group. A total of 147 out of 4,221 referred patients had a positive patch test to carvone. Sensitized patients had higher mean age and were primarily women; 73% had oral signs and 57% had oral lichen. Concomitant patch test reactions to gold, nickel and mercury were common. In the matched group-comparison carvone-positive patients had a higher frequency of oral lichen, but no difference was found in sensitization to gold and mercury.

Background: Carvone (L-carvone) is naturally found in spearmint oil and is considered a mild skin sensitizer. It commonly serves as a flavoring agent in toothpaste and other mint tasting products. There is recent evidence that carvone may have a relationship with oral lichenoid lesions (OLL). Objectives: The aim was to study the frequency of carvone contact allergy in a Swedish patch test population at the Malmö clinic and to investigate the characteristics of the group with special reference to OLL. Methods: A 15-year retrospective study including all consecutive patients tested positive for carvone with different series containing carvone. The patients’ records were reviewed in regard to symptoms, previous diagnoses, type of referrer and contact allergy. Results: Three thousand eight hundred and twelve patients were patch tested to different series containing l-carvone, the most common being the Swedish dental series. One hundred and forty-three patients (3.7%) were positive to carvone whereof 138 patients had records available for review. Of the carvone-sensitized patients, 46.9% had suspected or previously diagnosed OLL and 8.0% had dermal or genital lichen planus. The majority of the carvone-sensitized patients had also positive reactions to several other allergens. The most common allergens were spearmint oil (39.9%), gold (35.5%) fragrance-mix (17.4%) and nickel (15.5%). The majority of the carvone-sensitized patients with allergy to gold (30/49) or allergy to mercury (16/18) also had OLL. The male-to-female ratio was 1:4.75 among the carvone-sensitized patients compared to 1:2.55 in the overall test groups. Conclusions: The frequency of patients sensitized to carvone seems to correspond with previous findings. Concomitant contact allergy to gold or mercury was often associated with OLL and these patients were often referred for suspected allergy from d ental restorations. The data together with conclusions in recent reports suggests a relationship between OLL and l-carvone contact allergy. The relationship is yet unknown and needs further investigation.

BACKGROUND: Toothpastes have widespread use in the population, and contain flavours used to give a pleasant and often minty aroma. Flavours are prevalent allergens in toothpastes, and adverse reactions often present as perioral dermatitis or stomatitis. l-Carvone, a mint flavour found in spearmint oil, is one of these allergens. There are few studies on contact allergy to l-carvone, and some of them have indicated a positive relationship with oral lichenoid lesions. OBJECTIVES: To qualitatively and quantitatively investigate the presence of l-carvone in commercially available toothpastes on the Swedish market. METHODS: l-Carvone in 66 toothpastes was analysed with straight-phase high-performance liquid chromatography. The product labels were studied with regard to limonene. RESULTS: l-Carvone was found in 64 of 66 toothpastes (concentration: 0.00005-0.35%). In 10 of these, the concentration exceeded 0.1%. Higher concentrations of l-carvone were found if limonene was listed on the label. CONCLUSION: The majority of toothpastes on the Swedish market contain l-carvone, but the concentration hardly relates to the advertised flavour or labelled ingredients. It is hitherto unknown whether the found concentrations are sufficient for induction of contact allergy in individuals with healthy oral mucosa or in those with oral lichenoid lesions or other mucosal disease.

PURPOSE: To validate the well-known and often-used impression replica technique for measuring fit between a preparation and a crown in vitro. MATERIALS AND METHODS: The validation consisted of three steps. First, a measuring instrument was validated to elucidate its accuracy. Second, a specimen consisting of male and female counterparts was created and validated by the measuring instrument. Calculations were made for the exact values of three gaps between the male and female. Finally, impression replicas were produced of the specimen gaps and sectioned into four pieces. The replicas were then measured with the use of a light microscope. The values received from measuring the specimen were then compared with the values received from the impression replicas, and the technique was thereby validated. RESULTS: The impression replica technique overvalued all measured gaps. Depending on location of the three measuring sites, the difference between the specimen and the impression replicas varied from 47 to 130 mum. CONCLUSION: The impression replica technique overestimates gaps within the range of 2% to 11%. The validation of the replica technique enables the method to be used as a reference when testing other methods for evaluating fit in dentistry.