The aim was to measure variations in threshold for operative treatment of approximal caries in permanent teeth and the use of restorative materials, compared with results from studies conducted in Norway in 1983 and 1995. In 2009, a precoded questionnaire was sent electronically to 3,654 dentists with E-mail addresses in the member register of the Norwegian Dental Association. The questions were related to caries, treatment strategies and choice of dental materials. Replies were obtained from 61% of the dentists after two reminders. Restorative treatment of approximal lesions confined to enamel, based on radiographic appearance, was proposed by 7% of the dentists, compared with 66% in 1983 and 18% in 1995. Younger dentists, significantly more often than older, would defer operative treatment of approximal lesions until the lesion was visible in dentine. While tunnel preparation most often was the preparation of choice in 1995 (47%), saucer-shaped preparation was most favoured in 2009 (69%). Tunnel preparation was only preferred by 4% of the dentists. Resin composite was the restorative material preferred by 95%, compared with 16% in 1995. The corresponding values for conventional glass ionomer cement (GIC) were 1 versus 22%, for resin-modified GIC 1 versus 7%, and for a combination of GIC and resin composite 2 versus 22%. Compomer was preferred by 1% of the respondents. The authors conclude that treatment concepts for approximal caries have changed considerably during the last 26 years. In 2009, only 7% of dentists reported that they would treat approximal caries operatively before the lesion reached dentine.

This study aimed to investigate dentists' exposure to curing light and to obtain information about the dentists' knowledge on practical use and technical features of their curing lights as well as their safety awareness. A pre-coded questionnaire was sent electronically to all dentists (n=1313) in the Public Dental Service (PDS) in Norway in 2015. The Response rate was 55.8%. The dentists spent on average 57.5% of their working days placing restorations, ranging from 1 to 30 (mean 7.7, SD 3.6) restorations per day. The average length of light curing one normal layer of composite was 27s. The longest individual mean curing time per day was about 100 times higher than that of the lowest. The mean curing time for lamps of the lower reported irradiances was similar to the time representing exceedance of international guidelines for limit values for blue light to the eyes. Almost one-third of the dentists used inadequate eye protection against blue light. The odds of using adequate eye protection were significantly higher among young dentists (p<0.01). The majority of the respondents (78.3%) were unaware of the irradiance value of their curing lights, thus rendering the curing time uncertain. More dentists in this group did not perform regular maintenance of their curing lights compared with all respondents (17.1% vs. 3.3%, p<0.01). This study revealed considerable variations among Norwegian dentists in the Public Dental Service with respect to performance of light curing of restorations, safety awareness and technical knowledge of the curing light. The questionnaire study identifies specific knowledge gaps among Norwegian dentists with regard to curing lights and use of personal protection. Today's dependence on technology in dentistry necessitates that the operator possesses knowledge of essential technical specifications and safe use of devices and instruments routinely used in dental treatment.

Objective. To identify factors associated with dentists’ decisions on choice of restorative material in children and adolescents. Material and methods. In the period 2001–2004, 27 dentists in the Public Dental Health Service in Norway placed 4030 Class II restorations in 1912 patients. The reason for placement, previous caries experience (DMFT), oral hygiene, and characteristics of the cavity were recorded. Results. The most frequently used material was resin composite (81.5%), followed by compomer (12.7%), amalgam (4.6%), and glass ionomer cement (1.2%). Tooth-colored restorations were more frequently placed than amalgam in younger patients (p=0.017). Female patients received fewer amalgam restorations than male patients (p=0.006). Amalgam was more often used in patients with high DMFT (p<0.001) and more commonly in treatment of deeper dentine caries than caries near the dentino-enamel border (p=0.021). Amalgam was more frequently placed in molars than in premolars (p<0.001). In a logistic regression model, gender, DMFT, caries severity, and tooth type were significantly related to choice of material. Conclusion. Dentists’ choices of restorative material indicate that the majority prefer amalgam in more challenging restorations with respect to caries activity, lesion depth, and tooth type. The findings indicate that in a period when the use of amalgam was phasing out, resin composite was the predominant material of choice for Class II restorations in children and adolescents.

Amalgam was banned as a dental restorative material in Norway in 2008 due to environmental considerations. An electronic questionnaire was sent to all dentists in the member register of the Norwegian Dental Association (NTF) one year later, to evaluate dentists’ satisfaction with alternative restorative materials and to explore dentists’ treatment choices of fractured amalgam restorations. Replies were obtained from 61.3%. Composite was the preferred restorative material among 99.1% of the dentists. Secondary caries was the most commonly reported cause of failure (72.7%), followed by restoration fractures (25.1%). Longevity of Class II restorations was estimated to be ≥10 years by 45.8% of the dentists, but 71.2% expected even better longevity if the restoration was made with amalgam. Repair using composite was suggested by 24.9% of the dentists in an amalgam restoration with a fractured cusp. Repair was more often proposed among young dentists (p < 0.01), employees in the Public Dental Service (PDS) (p < 0.01) and dentists working in counties with low dentist density (p = 0.03). There was a tendency towards choosing minimally invasive treatment among dentists who also avoided operative treatment of early approximal lesions (p < 0.01). Norwegian dentists showed positive attitudes towards composite as a restorative material. Most dentists chose minimally- or medium invasive approaches when restoring fractured amalgam restorations.