The ultimate guide to restoration longevity in England and Wales. Part 1: methodology

The long-term oral health consequences of an amalgam phase-out

Understanding the long-term oral health implications of an amalgam phase-out is complex. However, amalgam is a simpler, cheaper, quicker, more predictable and effective material to place and replace than composite, which is the main alternative. It also has fewer postoperative complications in United Kingdom (UK) primary care and has been shown to be more cost-effective over a lifetime. Existing economic evaluations are limited, however, with rudimentary models which fail to consider clinicians and patients, and likely significantly underestimate the broader costs of placing composite compared to amalgam. Amalgam alternatives require improvement and their environmental impacts require characterisation. Composite restorations can be successful in extensive cavities, but they require much technical skill and expensive and time-consuming specialised equipment, which are not being commonly used in UK primary care, especially by National Health Service (NHS) dentists. Postgraduate composite education is not generally making UK clinicians confident when faced with difficult cavities and requires improvement. Expert consensus on the use of techniques to restore varying cavity presentations with composite would help to guide this, while also considering how its dissemination could be improved. NHS clinician fees are significantly lower than in Europe. The NHS system therefore essentially incentives the use of amalgam and disincentivises the use of expensive and time-consuming recommended equipment for composite restorations. This has likely contributed to a failure of clinicians to upskill and be confident in providing posterior composite restorations safely. These issues, alongside a loss of trust, have led to dentists leaving the NHS, which has created access issues for patients, disproportionately affecting the most at need in society. An amalgam phase-out would almost certainly exacerbate this issue, widening existing health inequalities while not providing restoration characteristics which the most affected patients most value. Failure to urgently address these issues risks an oral health crisis in the UK if amalgam is imminently phased out.

Principles guiding the restoration of the root-filled tooth

Endodontic treatment is usually required because of significant coronal disease or traumatic tissue loss. The restoration of the subsequently endodontically treated tooth is also complicated by the reduction in its structural strength consequent to accessing the pulp chamber and the removal of radicular dentine during root canal instrumentation, alongside some alteration of dentinal properties during disinfection by chemical agents, prior to obturation. A loss of proprioceptive feedback, which may lead to increased loading, can place further stress on the already very compromised structure. This article considers the principles of restoring endodontically treated teeth: assessing restorability, providing a coronal seal to prevent reinfection, and gaining retention for a core where necessary, to restore aesthetics and function. Consideration is given to the patient and material factors that influence the decision to restore the treated tooth using direct or indirect restorations. Specific attention is given to anterior or posterior teeth and the various materials which may be used in their overall restoration with their associated, probable, longevity.

SNOMED-CT and learning health systems for NHS dentistry - a dream needing to become reality

There has been discussion and confusion about SNOMED-CT (systematised nomenclature of medicine clinical terminology), learning health systems (LHSs) and their relevance in dentistry. This article aims to provide an overview of SNOMED-CT, LHSs and the all-too-often omitted patient and service benefits from their use. LHSs are delivering impactful benefits to patients and services globally in medicine. There are some examples in dentistry, but these are few and lack the nationalised co-ordinated efforts supporting general medical practice (GP) electronic health record (EHR) databases. These impacts require research and insights from large-scale, linked EHR databases, for which SNOMED-CT will greatly facilitate. This opinion piece discusses SNOMED-CT, LHSs and the current state of EHR databases in dentistry with comparison to medical practice. Impactful examples of GP EHR database research are presented, as well as the potential benefits and disadvantages of EHR-based approaches in dentistry. Barriers to creating large dental EHR databases in the UK are discussed and potential solutions offered. Lastly, there is a call to action for multiple stakeholders, including dental clinicians, patients, academics, public health professionals, software suppliers, commissioners, and the government to co-ordinate efforts, including that of SNOMED-CT implementation, so that dentistry does not get excluded from the benefits of integrated LHSs.

Multifactorial Contributors to the Longevity of Dental Restorations: An Integrated Review of Related Factors

PURPOSE

This integrated review aims to identify and analyze the multifactorial contributors to the longevity of direct restorations, focusing on tooth-, patient-, and dentist-related factors.

MATERIALS AND METHODS

A search of the literature was performed using an electronic database, PubMed/Medline, Web of Science, and Scopus, on papers published between 1980 and 2024. The titles and abstracts of papers that evaluated aspects categorized into tooth-related, patient-related, and dentist-related factors influencing restoration failure were selected and screened. Full-text assessments were conducted, and the extracted data were compiled, summarized, and synthesized. The reference lists of the collected papers were also screened, and relevant citations were included in this review. Data were gathered from clinical and laboratorial studies, systematic reviews, and meta-analyses to provide a comprehensive understanding of restoration longevity.

RESULTS

Among the tooth-related factors, multiple-surface restorations, deep margins, tooth location, and tooth vitality significantly impact restoration survival. Patient-related factors such as medical conditions, risk predictors of caries, age, sex, parafunctional habits, smoking, periodontal health, number of restorations, and socioeconomic status all play crucial roles. Regarding dentist-related factors, the decision-making process, age, experience, and dentist manual dexterity are vital aspects. Furthermore, the technique used, including isolation methods for moisture control, as well as the type of dental practice (large group vs. small practice), notably influenced the restoration survival.

CONCLUSIONS

The longevity of dental restorations is influenced by a complex interplay of tooth-related, patient-related, and dentist-related factors. Strategies to improve restoration outcomes should consider all these multifactorial contributors. Continuing professional education, diligent patient guidance on the factors that influence restoration survival, careful material selection and restorative technique, and tailored individual treatment are crucial factors to reduce failure rates and improve the lifespan of restorations.

Survival analysis of posterior composite restorations in National Dental PBRN general dentistry practices

OBJECTIVE

Quantify the survival of posterior composite restorations (PCR) placed during the study period in permanent teeth in United States (US) general dental community practices and factors predictive of that survival.

METHODS

A retrospective cohort study was conducted utilizing de-identified electronic dental record (EDR) data of patients who received a PCR in 99 general dentistry practices in the National Dental Practice-Based Research Network (Network). The final analyzed data set included 700,885 PCRs from 200,988 patients. Descriptive statistics and Kaplan Meier (product limit) estimator were performed to estimate the survival rate (defined as the PCR not receiving any subsequent treatment) after the first PCR was observed in the EDR during the study time. The Cox proportional hazards model was done to account for patient- and tooth-specific covariates.

RESULTS

The overall median survival time was 13.3 years. The annual failure rates were 4.5-5.8 % for years 1-5; 5.3-5.7 %, 4.9-5.5 %, and 3.3-5.2 % for years 6-10, 11-15, and 16-20, respectively. The failure descriptions recorded for < 7 % failures were mostly caries (54 %) and broken or fractured tooth/restorations (23 %). The following variables significantly predicted PCR survival: number of surfaces that comprised the PCR; having at least one interproximal surface; tooth type; type of prior treatment received on the tooth; Network region; patient age and sex. Based on the magnitude of the multivariable estimates, no single factor predominated.

CONCLUSIONS

This study of Network practices geographically distributed across the US observed PCR survival rates and predictive factors comparable to studies done in academic settings and outside the US.

CLINICAL SIGNIFICANCE

Specific baseline factors significantly predict the survival of PCRs done in US community dental practices.

Unlocking the potential of NHS primary care dental datasets

Introduction Maximising the use of routinely collected health data for research is a key part of the UK Government's Industrial Strategy. Rich data are generated by NHS primary care dental services, but the extent of their use in research is unknown.Aims To profile the utility of the post-2006 NHS dental datasets for research, map how they have been used to date and develop recommendations to maximise their utility.Methods The content of and access to the four UK NHS dental datasets was collated using publicly available information and a free-text questionnaire, completed by the relevant data controllers. A scoping review was carried out to identify and map literature that has utilised NHS dental activity data.Results The contents of the UK NHS dental activity datasets are described, alongside how they may be accessed for research. Strengths and weaknesses of these datasets for research are highlighted. The scoping review identified 33 studies which had utilised NHS dental activity data since 2006. We classified 15 as public health practice, 11 as service evaluation and 7 as research.Conclusion In comparision to other NHS activity datasets, it appears that the UK dental datasets have been underutilised for research. We make 11 recommendations on how their utility for research may be increased.

A retrospective clinical study on the survival of posterior composite restorations in a primary care dental outreach setting over 11years

OBJECTIVES

To investigate the survival in terms of time to re-intervention of composite restorations in posterior teeth among patients attending for treatment at a primary care dental outreach setting over an 11-year period and to determine whether dental, patient or operator factors influenced this.

METHODS

Electronic primary dental care data were collected on individual patients, including information on their dental treatment and socio-demographics as well as service provision, key performance indicators and student activity.

RESULTS

A total of 1086 patients had at least one posterior composite placed between 2007 and 2018. This amounted to 3194 restorations placed of which 308 had a re-intervention within the 11-year period. For all restorations, the annual failure rate at 1 year was 5.73 %, at 5 years was 16.78 % and at 10 years was 18.74 %. A logistic regression showed that when compared to the least deprived 5^th quintile, the most deprived 1^st and 2^nd quintiles were significantly less likely to have a re-intervention, being 49.2 % (p = 0.022) and 53.2 % (p = 0.031) less likely, respectively.

CONCLUSIONS

The survival rates of posterior composite restorations placed at a single outreach centre providing undergraduate dental training in the South of England, mirrors other studies. The new findings presented suggest similar re-intervention rates between dental students and dental hygiene-therapy students. This study's findings around patient deprivation and rate and time of re-intervention raises important questions related to the need for targeted dental and after care for certain groups in the population.

CLINICAL SIGNIFICANCE

Understanding the factors associated with re-intervention of restorations provided to patients has an impact on patients and dental practices. Also, as we consider widening use of skill mix in dentistry to increase access to care, parity in provision of treatments within the dental team increases opportunities for delegation of tasks.

Six-year survival of single crowns - A massive data analysis

OBJECTIVES

Numerous clinical trials have proven the long-term stability of metal and metal-ceramic crowns. However, data on their performance under practice conditions are rare.

PURPOSE

To evaluate the longevity of crowns by means of massive data analyses.

METHODS

The data were extracted from the data warehouse of a major German national health insurance company (BARMER, Berlin, Germany). The analysis focused on crown types with the lowest deductibles. Metal crowns and metal-ceramic crowns with ceramic veneering on the vestibular aspects of teeth 15-25 and 34-44 placed from 2012 to 2017 were included. The placement of the crowns, crown removals and tooth extractions were identified using the corresponding fee codes. Kaplan-Meier survival analyses were conducted for the outcomes "crown removal or extraction" and for "extraction".

RESULTS

The cumulative six-year survival rates were 88.0 % for the outcome "crown removal or extraction" and 92.5 % for the outcome "extraction" (N = 192,868). The survival functions had slightly steepening but close to linear courses.

CONCLUSIONS

The outcome of the treatment with metal and metal-ceramic crowns was moderately inferior in comparison to clinical trials. However, treatment with metal and metal-crowns is judged to be a reliable and safe option under practice conditions.

CLINICAL SIGNIFICANCE STATEMENT

Clinicians must inform patients about potential treatment outcomes. Therefore, additional knowledge about single crown outcomes under general practice settings based on large database analyses is important.

Type and time of first re-intervention of posterior restorations - 13-year scenario at the public dental service

Objectives: We investigated the first re-interventions of two- and three-surface direct restorations on posterior teeth, specifically noting the type and time of the first re-intervention.Materials and methods: In 2002, altogether 5542 posterior two- and three-surface composite and amalgam restorations were done for 3051 patients aged 25-30 years at Helsinki City Public Dental Service (PDS). Based on electronic patient records, we analysed all restorations (n = 2445) having re-intervention during a 13-year follow-up. We recorded the type of tooth, restoration size, and type of first re-intervention. The time to re-intervention was the interval between the date of the placement of restoration at the year 2002 and its first re-intervention.Results: Restorative treatment was the most common (77.9%) first re-intervention, followed by endodontics (11.5%), extractions (5.2%), and other (5.4%). Males, more frequently than females, had extraction or endodontics as first re-intervention. The average time to re-intervention was 5.7 years (SD 3.8; median 5.2). Both median and mean times were shortest for cases involving endodontics or extractions.Conclusions: For the majority of two- and three-surface posterior restorations, the first re-intervention is restorative (replacement or repair of restoration). The shortest time to re-intervention is for restorations that have endodontics or extraction as the first re-intervention.

The differences between three performance measures on dental restorations, clinical success, survival and failure: A matter of perspective

OBJECTIVES

The aim of this retrospective methodology study was to investigate the influence of using different definitions for restoration failure and inclusion criteria on restoration longevity expressed in AFR.

METHODS

EPF from fifteen general dental practices were used for collecting the data for this study. From the EPF, 321,749 composite restorations placed in 52,245 patients by forty-seven GDPs between January 2000 and December 2011 were included. Kaplan-Meier statistics were applied and mean AFRs over 2, 5 and 10 years were calculated. The effect on the AFR of using different levels of failure: based on Claims data (CD), Success (SUC), Survival (SUR) and different inclusion criteria of tooth/restoration variables were reported.

RESULTS

Highest AFRs were found for level CD, in which every intervention was considered as failure, and the lowest AFRs for level SUR in which repairs and an endodontic treatments were not considered as a failure. AFRs increased when the observation period prolonged especially for SUR, followed by SUC and CD. An overview of long-term survival studies showed a wide variation in study design, performed clinical examination (USPHS criteria or GDP), number of restorations included, description of restoration failure and found AFRs for CD, SUC and SUR.

SIGNIFICANCE

Using failure criteria, Success and Survival, in future clinical studies would enable a better comparison of studies as well as demonstrate the impact of more conservative restorative intervention protocols on patient care.

Electronic primary dental care records in research: A case study of validation and quality assurance strategies

BACKGROUND

In dentistry, the use of electronic patient records for research is underexplored. The aim of this paper is to describe a case study process of obtaining research data (sociodemographic, clinical and workforce) from electronic primary care dental records, and outlining data cleaning and validation strategies. This study was undertaken at the University of Portsmouth Dental Academy (UPDA), which is a centre of education, training and provision of state funded services (National Health Services). UPDA's electronic patient management system is R4/Clinical +. This is a widely used system in general dental practices in the UK.

METHOD

A two-phase process, involving first Pilot and second Main data extraction were undertaken. Using System Query Language (SQL), data extracts containing variables related to patients' demography, socio-economic status and dental care received were generated. A data cleaning and validation exercise followed, using a combination of techniques including Maletic and Marcus's (2000) general framework for data cleaning and Rahm and Haido's (2010) principles of data cleaning.

RESULTS

The findings of the case study support the use of a two-phase data extraction process. The data validation processes highlighted the need for both manual and analytical strategies when cleaning these data. Finally, the process demonstrated that electronic dental records can be validated and used for epidemiological and heath service research. The potential to generalise findings is great due to the large number of records. There are, however, limitations to the data which need to be considered, relating to quality (data input), database structure and interpretation of data codes.

CONCLUSION

Electronic dental records are useful in health service research, epidemiological studies and skill mix research. Researchers should work closely with clinicians, managers and software developers to ensure that the data generated are accurate, valid and generalisable. Following data extraction the researchers need to adapt stringent validation and data cleaning strategies to guarantee that the extracted electronic data are accurate.

The role of the randomised controlled trial in restorative dentistry and the correct purpose of observational data

It has been argued that the randomised controlled trial design is unsuitable for restorative dentistry and that cohort studies or the analysis of large observational datasets without randomisation is more suitable. This opinion article examines why randomisation in clinical trials is needed and why big observational data is not enough for clinical inference.