Restorative dentistry

  1. Phasing down opinions
The Minamata Convention embodies a worldwide reduction in the production and use of mercury and mercury-containing products and processes, including a phase-down of dental amalgam. An online survey relating to aspects of, and attitudes to, the use of direct restorative materials was distributed to dentists in Australia.  Of the 408 respondents, 87% strongly disagreed that amalgam was a technically more difficult material to place compared with resin composite; and 82% strongly disagreed that placement time was longer. The factors considered most important when choosing a direct restorative material included moisture control and aesthetics; least important factors were cost and time to place. There was consensus that amalgam is not more technically difficult to use, place or finish than resin composite and vice versa. When choosing a direct restorative material, clinical factors considered to be of greatest importance were moisture control, aesthetics and the need to apply minimally invasive approaches. There was little difference in the opinions of users and non-users of amalgam with respect to these findings.

Alexander G et al. Dentists’ restorative decision-making and implications for an ‘amalgamless’ profession. Part 4: clinical factor. Australian Dent J 2017 Apr 24.

Q In this survey, which three factors were considered most important in choosing a direct restorative material?
A Cost, time to place and moisture control
B Moisture control, aesthetics and cost
C Aesthetics, cost and minimally invasive approaches
D Moisture control, aesthetics and minimally invasive approaches

  1. Longevity in a direct light
To analyse the clinical success of direct light-activated composite resin restorations in posterior teeth all restorations performed by the first author in his private practice, in a 5- to 20-year period were reviewed. To be included in the study, the restorations had to have been in function for at least 5 years and had to have been placed between October 1993 and October 2008. The established failure criteria were: tooth and/or restoration fracture, secondary caries, endodontic treatment, or tooth loss. At the time of the examinations, 103 (98%) restorations were in function, and 98 (95.1%) were rated as clinically successful. Two restorations failed (2%). The observed mean survival time of restorations that remained functional was 11 years and 7 months. In the present report, direct light-activated composite resin restorations in posterior teeth showed a high clinical success rate and long-term mean survival time. These composite resins might be considered the material of choice to restore medium, extended, and in some clinical situations, large preparations in posterior teeth.

Borgia E, Baron R, Borgia JL. Quality and survival of direct light-activated composite resin restorations in posterior teeth: a 5- to 20-year retrospective longitudinal study. J Prosthodontics 2017 May 17.

Q Which of the following statements fairly represents the results of this review?
A 95.1% of the restorations were rated as clinically unsuccessful
B Direct light-activated composite resin restorations in posterior teeth showed an equivocal clinical success rate
C The observed mean survival time of restorations that remained functional was 11 years and 7 months
D Secondary caries was not considered a criterion for failure

  1. Anterior performance assessed
This practice-based study investigated the performance of a large set of anterior composite restorations placed by a group of 47 general dental practitioners. Based on data from electronic patient files, the longevity of 72,196 composite restorations was analysed, as placed in 29,855 patients between 1996 and 2011. Annual failure rates (AFRs) were calculated, and variables associated with failure were assessed. Among dentists, a relevant variation in clinical performance of restorations was observed, with an AFR between 2% and 11%. The risk for restoration failure increased in individuals up to 12 y old, having a 17% higher risk for failure when compared with the age group of 18 to 25 years. In both multivariate models, there was a difference in longevity of restorations for different teeth in the arch, with fillings in central incisors being the most prone to failure and replacement. It was concluded that anterior composite restorations placed by general dental practitioners showed an adequate clinical performance, with a relevant difference in outcome among operators.

Collares K et al. Longevity of anterior composite restorations in a general dental practice-based network. J Dent Res 2017 96: 1092-1099.

Q Restorations in which type of teeth were more prone to failure?
A Central incisors
B Lateral incisors
C Canines
D Premolars

  1. Raising the stakes
The aim of this audit was to monitor the outcome of composite restorations placed between 2012 and 2016 at an increased vertical dimension in patients with severe tooth wear, over more than one appointment and the outcome monitored for up to 14 months. Outcome was assessed as either success or failure (minor or major) in 35 patients (mean age 45 years) who received 251 restorations. The patients had a mean of 11.51 (range 4 to 16) occluding pairs of teeth. There was a total of 40 restoration failures (17%) which was an 83% success rate based on the total number of restorations. For the patient-based data, 14 patients (39%) had no chips or bulk factures while 22 (61%) patients had failures, of which 60% were chips and 40% bulk fractures. Restoration of worn teeth with composites is associated with a high incidence of fractures. The restoration of worn teeth with composite can involve regular maintenance following fractures and patients need to be aware of this when giving consent.

Bartlett D, Varma S. A retrospective audit of the outcome of composites used to restore worn teeth. Br Dent J 2017 223: 33-36.

Q Restoration of worn teeth with composites:
A Is associated with a high incidence of fractures
B Can involve regular maintenance
C Involves risks of which patients need to be aware when giving consent
D All of the above