The Impact of Type 2 Diabetes on Oral Health Among Adults in England (2020–2025): A Systematic Review of Public Health Evidence

Abstract

This is a systematic review that explores barriers to oral healthcare in older adults aged 60 years with type 2 diabetes in England. The paper examines 2020-2025 evidence of public health and includes the influence of the COVID-19 pandemic. Thematic analysis of 19 sampled studies reveals that there are major structural disproportions and service interruptions. The results indicate that the high prices keep many elderly patients out of the way of obtaining the needed restorative dental services. Clinical disconnect exists in medical and dental practices that frequently result in the loss of diagnosis. The study finds that the existing system does not offer integrated care to this group of people. Some of the recommendations include abolishing dental bills for diabetic patients and consolidating medical and dental records of patients.

 

Acknowledgments

I would be grateful to say that I was guided by my supervisor very professionally. I needed their positive criticism, and support, which proved to be critical towards ensuring that I was successful in doing this dissertation. The academic staff should also be credited with their valuable advice and help during this course, which I would like to thank as well. I would like to give my family and friends my utmost thanks as they have been very patient and encouraging. Their trust in me is what gave me the great drive needed to complete this demanding research. Lastly, I do not ignore the authors of the studies I have reviewed here to recognize that they have given the evidence needed.

 

Table of Contents

1. Introduction and Context 7

1.1 Background and Context 7

1.3 Rationale for the Study. 9

1.4 Research Aim and Objectives. 10

1.5 Research Question. 10

1.6 Dissertation Structure. 10

2. Literature Review.. 12

2.1 Introduction. 12

2.2 The Pathophysiology of Type 2 Diabetes. 12

2.3 Common Oral Health Outcomes in Adults. 14

2.4 The Bidirectional Link Between Diabetes and Oral Health. 15

2.5 Public Health Policy in England. 16

2.6 Key Confounding Variables. 17

2.7 Identifying the Research Gap. 18

2.8 Chapter Summary. 18

3. Methodology. 19

3.1 Introduction. 19

3.2 Research Philosophy. 19

3.3 Research Approach. 19

3.4 Research Design. 20

3.5 Search Strategy. 20

3.6 Inclusion and Exclusion Criteria. 21

3.7 Screening and Selection Process. 22

3.8 Data Analysis. 23

3.9 Ethical Considerations. 26

3.10 Chapter Summary. 27

4. Data Analysis and Finding. 28

4.1 Introduction. 28

4.2 Structural and Systemic Barriers in the NHS. 28

4.3 Economic Barriers and Affordability. 30

4.4 Clinical Integration Gaps: The "Silo" Effect 31

4.5 Vulnerabilities of the Ageing Population. 32

4.6 Chapter Summary. 33

5. Discussion. 35

5.1 Introduction. 35

5.2 Discussion on Secondary Data Analysis. 35

5.3 Summary. 38

6. Conclusion & Recommendations. 39

6.1 Conclusion. 39

6.2 Recommendations. 39

6.3 Future Scope. 40

References. 41

Appendix 1: PRISMA.. 50

Appendix 2: Search Results. 51

Appendix 3: Ethics Approval 52

 

 

 

 

1. Introduction and Context

1.1 Background and Context

Type 2 diabetes is one of the most important health problems of the population in England. Type 2 diabetes is one of the most important health problems of the population in England. Diabetes type 2 is a chronic metabolic disorder. It is a condition related to the decreased blood sugar metabolism within the body (Dilworth, Facey, & Omoruyi, 2021). This is the diagnosis of millions of people living in England now. The rising cases demand a great deal of heavy load on the National Health Service. Treatment of type 2 diabetes is a continuous way of healthcare. The effects such as cardiovascular disease, stroke, renal failure, nerve damage, and loss of sight are called complications. Lower limb amputations are also the most common cause of diabetes. The economic burden to the nation is enormous, as it is the millions of pounds every year.

Diabetes is a priority in Public Health England, and its successor, the Office for Health Improvement and Disparities (Kilvert & Fox, 2023). Diabetes Prevention Programme is a large-scale national program of the NHS. It also seeks to determine high-risk people and provide lifestyle-change support. In spite of these measures, there is not an equal distribution of the weight of type 2 diabetes. The issue of type 2 diabetes is therefore key to improving the national health outcomes (Ernawati, Wihastuti, & Utami, 2021).

Periodontal health is an important and inseparable part of health and wellness. It goes much further than the mere lack of dental illness. Periodontal health is a condition of being without chronic inflammation in the gums. It involves the absence of oral cancers, oral infections, severe gum disease, and loss of teeth. Good periodontal health implies proper working of the mouth. With healthy teeth and gums, the individuals can eat, talk and socialise without interference or embarrassment. On the other hand, poor periodontal health has a tremendous negative effect on the quality of life. It brings about physical pain and chewing problems. It also causes psychological pain, low self-worth, and loneliness. Periodontal health is regarded by many and even certain health systems as a distinct entity to general medical care (Jiang et al. 2021). This historical division poses great obstacles to proper management of chronic diseases.

There is a close, two-way relationship between poor periodontal health and type 2 diabetes. Patients with diabetes are quite vulnerable to periodontal diseases. There are biological factors that contribute to this risk increase. Unregulated blood glucose levels provide an opportunity favourable to pathogenic oral bacteria (Ahmad & Haque, 2021). The sugar level goes up in the saliva and the fluid surrounding the teeth. This enhances the growth of bacteria. The result of this is a very high possibility of developing periodontal disease. Periodontal disease is a severe gum inflammatory disease. It destroys the soft tissue and in severe cases, the bone which supports the teeth. Saliva production among diabetic patients is also slowed down.

Immunoreactivity of the body is frequently impaired in diabetic individuals. This complicates the resistance to periodontal infections. Dental postoperative healing is also often delayed. The reciprocation is also a mutual one. Diabetes increases the difficulty in the management of periodontal health (Gonzalez-Moles & Ramos-Garcia, 2021). Severe periodontal disease is a condition of low-grade and chronic inflammation. The chemicals released in the gums in an inflammatory state get into the bloodstream. The main objective of diabetes management is good glycaemic control. A persistent periodontal infection actively opposes this very important objective. Periodontal health management is thus a very critical component of diabetes management.

The implementation of periodontal health in the general diabetes practice is a major social health issue in England. The NHS is a significant obstacle in its structure. Dental care and general medical care are normally commissioned and provided separately. The effect of this separation is that periodontal health is not given much attention in the diabetes care plans. Diabetic patients undergo annual eye, feet and kidney specialist examinations (Agrawal et al. 2025). Their periodontal health is hardly part of such a review. The adult smokers over 60 years in England who have diabetes require clarity and consistent instructions. Health care providers that work with diabetic patients should know the diabetes position of their patients (Sørensen et al. 2020). The awareness enables them to offer the right advice and customized treatment.

It is especially crucial with regard to the period between 2020 and 2025. The COVID-19 disrupted regular dental services in England drastically. Ease of appointments was very limited. This generated a huge queue of care. It possibly aggravated the already existing periodontal health issues to the entire population. Individuals having chronic illnesses such as diabetes were particularly susceptible to this period (Airhihenbuwa et al., 2021).

1.3 Rationale for the Study

This study is required because it is handling a unique and disturbing age. The 2020-2025 period was seen as the one marked by the COVID-19 pandemic. It was the first time in the history of the NHS dental services to halt regular services and it was very cruel when the pandemic erupted (Plessas et al. 2021). Access to care was not easily available and this created a huge backlog. This situation must have increased the underlying periodontal health issues of the vulnerable populations. The adults over 60 years with diabetes type 2 were found to be at risk especially the male smokers. The fact that barriers to periodontal care need to be understood during this very period is also clear. The findings will be timely evidence to the policy makers. This will help come up with better and more integrated care experiences to diabetic adults in England.

1.4 Research Aim and Objectives

Aim:

●      To systematically review public health evidence on the barriers to accessing oral healthcare for adults’ smokers aged over 60 with type 2 diabetes in England (2020–2025).

Objectives:

●      To identify the reported barriers to accessing NHS dental services for adults’ smokers over 60 with type 2 diabetes in England.

●      To synthesise findings from published research and public health reports to determine the extent of these oral health outcomes.

●      To analyses identified trends or challenges related to oral health and diabetes management between 2020 and 2025.

●      To identify gaps in the current evidence, base to provide recommendations for public health policy and future research.

1.5 Research Question

●      What does public health evidence from 2020–2025 reveal about the challenges and barriers in accessing oral healthcare for adults’ smokers aged over 60 with type 2 diabetes in England?

1.6 Dissertation Structure

This dissertation is divided into 6 chapters. Chapter 2 takes a review of literature on diabetes and oral health. It also talks about the policies in England regarding public health. The systematic review methodology is described in chapter 3. It describes a search plan, selection criteria and data analysis plan. Chapter 4 includes the results of the chosen research. In Chapter 5, the interpretation of these results is provided. In this discussion chapter, the findings are linked to the research question. Chapter 6 provides a conclusion to the study. It reports on the major findings and gives recommendations on the recommendations to the public health.

 

2. Literature Review

2.1 Introduction

This chapter reviews the literature that is available. It provides a basis of the systematic review. This is done to provide a summary of existing information on the topic of oral health and type 2 diabetes. It examines the developed biological connections between the two disorders. It also looks at the applicable policies of public health that are in operation in England. This review determines what the research already knows. It also brings out the particular gap in the research. The gap is related to the oral health of adult’s smokers over 60 years in England in the 2020-2025 period.

2.2 The Pathophysiology of Type 2 Diabetes

Figure 1: 2. Type 2 Diabetes Mellitus (T2DM) risk factors

(Source: Galicia-Garcia et al. 2020)

The following diagram represents etiology and pathology of Type 2 Diabetes Mellitus (T2DM). The upper part is a differentiation of non-modifiable risk factors (genetics, ethnicity) and the modifiable ones (diet, obesity). The bottom section describes physiological cascade events resulting, such as mitochondrial dysfunction, gut dysbiosis, and inflammation to induce oxidative stress (ROS) and a so-called metabolic memory maintaining insulin dysfunction. Diabetes type 2 is a chronic metabolic disease. It interferes with the normal process of the body regulating the levels of blood glucose, otherwise known as blood sugar (Goyal, Singhal & Jialal, 2023). The cells in the body require glucose as their major source of energy. This sugar is derived from the food we consume, especially carbohydrates. Insulin is a hormone that is vital in keeping the blood glucose level normal (Rahman et al., 2021).

Insulin is analogous to a key; cell membranes are opened.  Glucose is subsequently employed in the cells to supply energy. The process assists in maintaining the levels of blood glucose in a healthy and small range (Hantzidiamantis, Awosika & Lappin, 2024). The characteristic of type 2 diabetes is insulin resistance. This disorder starts when cells of the body cease to respond to the signal of insulin in the right manner. The muscle, fat, and liver cells get desensitised to the hormone.

This demand stays high for months or years, thus destroying the beta cells. They also lose the capacity to produce enough insulin slowly. This phase is characterised by the transition of insulin resistance to developed type 2 diabetes. The pancreas is unable to create sufficient insulin to control the glucose level. The level of blood glucose then begins to increase steadily. It is a chronic experience of the elevated blood sugar level and is called hyperglycaemia. The clinical manifestation of diabetes is hyperglycaemia.

A number of things lead to resistance to insulin. The greatest risk factor is obesity, especially excess abdominal fat. The fat is metabolically active and secretes. These chemicals disrupt the insulin signalling. The lifestyle adopted (sedentary lifestyle), characterised by low levels of physical activity, also fosters insulin resistance. Another factor is age; the condition is more prevalent in individuals who are above 40. Some ethnic groups are prone in their genes as well. This involves South Asians, African-Caribbean and Black Africans.

2.3 Common Oral Health Outcomes in Adults

The general adult population is dealing with different oral health problems. This is more prevalent or severe in patients with system investment illnesses like diabetes. Periodontal disease is among the primary wishes. It is an inflammatory disorder of the tissues supporting the teeth that is long term. Gingivitis is reversible and it is the onset of the disease given that it is inflammation of the gums. The gums are haemorrhagic, swollen and erythematous. Gingivitis develops into periodontitis when it goes untreated. In between the teeth and the gums there are some spaces. These pockets are enhanced by the loss of bone. The teeth also get loose and mobile and they can tend to lose teeth. Periodontitis is one of the major oral diagnosis results of diabetes (Preshaw et al., 2012). Tooth decay or dental caries is another widespread effect. It is a preventable oral disease. Such bacteria are found in the plaque of the teeth which is a sticky film that forms on the teeth. When the sugar and carbohydrates are consumed, these bacteria metabolise the sugars. Other predisposing factors that make one susceptible to caries include unhealthy mouth, high intake of sugar, and low saliva levels. Dry mouth is referred to as Xerostomia or objective state of the oral dryness. In most instances, it can be occasioned by the regular reduction of salivary flow. Saliva is very important in maintaining health in the mouth. It disables the acidic secretions of the bacteria of the plaque after the food intake. Recovery of these protective functions is thus impaired by a reduced flow of saliva. The Xerostomia makes the mouth uncomfortable. It is also extremely harmful to the dental caries and oral infections (American Diabetes Association, 2023). Oral infection is another negative consequence. Commonly used are the fungal infection especially oral candidiasis (thrush). It is Candida albicans fungal overgrowth. The fungus is prevalent in the mouth in low amounts. Reduction in the quantity of saliva, high concentration of sugar in the saliva and poor immune system offer a good environment to its excessive growth (Centers for Disease Control and Prevention [CDC], 2023). The Candidiasis presents itself in the form of white spots in the mouth.

2.4 The Bidirectional Link Between Diabetes and Oral Health

Broad indications of a reciprocal relationship between diabetes and oral health are verified (Gurav, 2022). This association is the most evident in periodontal disease. The interrelation suggests that all states make each other worse. First, type 2 diabetes exposes a person to periodontitis to a great extent. The studies have shown that diabetic patients are about three times more likely to be affected by periodontitis (Preshaw et al., 2012). Severity of gum disease is also linked with glycaemic control. The patients with higher levels of blood sugar are prevalent with more advanced periodontitis. It inhibits the work of the white blood cells. It is these cells which are necessary to combat oral bacteria. Collagen is a significant protein present in the gum tissue, and its existence is also affected by the presence of high glucose levels. In proteins, glucose molecules are attached to each other forming Advanced Glycation End-products (AGEs). These AGEs make gum tissues unable to repair themselves. They also lead to excessive response of inflammatory reactions to the oral bacteria (Preshaw et al., 2012). This means that the gums become plaque destructive. Active periodontitis is a chronic bacterial infection. It results in the huge inflamed gum pockets area. It is not a solitary mouth infection. It leads to the issue of release of the chemicals also known as inflammatory mediators into the bloodstream (Kaur et al., 2013). These are the mediators such as the TNF-alpha that are found throughout the body. They supplement systemic, low-grade inflammations (Gk et al., 2022). This is among the primary causes of insulin resistance in the influence of this systemic inflammation. The insulin signalling is interfered with by the inflammatory chemicals. This makes the body cells insulin resistant (Kaur et al., 2013). The research has revealed the presence of positive relationship between the rates of HbA1c and the levels of periodontitis. HbA1c is the most significant blood test which tests average blood sugar within 3 months. Poor gum disease is associated with the rise in the HbA1c. Treatment studies also confirm the relationship. Systematic reviews have been effective in clinical trials (Umezaki et al., 2025). They found out that periodontal disease is treated which improves glycaemic control (Abueida et al., 2025). Non-surgical treatments which include scaling and root planing remove the bacteria plaque and gum inflammation. This, subsequently, results in a small yet statistically significant reduction in the amount of HbA1c (Preshaw et al., 2012; Umezaki et al., 2025).

2.5 Public Health Policy in England

The public health policy in England applies different policies to treat diabetes and dental health. One of the barriers is this division. Diabetes care is among the priorities of the NHS. The NHS Long Term Plan offers the specific goals of the diabetes management improvement. This entails the growth of the NHS Diabetes Prevention Programme. It also involves the improvement of access towards organised learning and self-management support (Ernawati, Wihastuti, & Utami, 2021). The annual checks system is one of the key elements of the diabetes policy. The diabetic individuals are advised to review their eyes, feet, and kidney after every one year. In England, there is a different framework in which dental health policy is executed. Dental care in the NHS is commissioned by NHS England. Independent contractors provide it. Access to NHS dentistry has been a health issue. In 2020-2025, this problem was exasperated to a significant degree. The COVID-19 pandemic of 2020 led to the closure of most dental practices (Iqbal et al., 2022). This led to huge line of treatment. Government policies during this time were directed towards controlling infections (CQC, 2021). This policy environment made access to routine dental care very challenging, especially to at-risk groups (Association of Dental Groups, 2022). Some of the policy documents acknowledge the relationship between oral and general health. Public Health England, formerly named Office for Health Improvement and Disparities (OHID) published guidance. As an example, in case, it is better oral health delivery, which provides evidence-based guidance to dental teams. Oral health is a part of guidelines given by National Institute of Health and Care Excellence (NICE) on type 2 diabetes. NICE revised its guidelines in 2022 (NG17, NG18, and NG28) to include periodontitis as a complication of diabetes in their list (British Society of Periodontology and Implant Dentistry [BSP], 2022). They suggest that the oral health of the patients ought to be examined by the medical teams. They also recommend that the patients should be referred to a dentist (NICE, 2022). Disproportionately impacted by diabetes and poor oral health are deprived communities (Kilvert and Fox, 2023). Public health plans should get rid of these gaps. As an example, the Soft Drinks Industry Levy policy concentrates on the decreasing sugar. No specific and combined oral health and diabetes policies exist, but these are among the wider strategies (NHS England, 2023).

2.6 Key Confounding Variables

One of the major problems facing this study is the ability to isolate the particular influence of diabetes on the oral health of the study. Oral health is a multi-factorial concept since it is highly dependent on lifestyle and individual behaviours. These are the causal factors, which are called confounding variables, which are personal hygiene, high-sugar diets, smoking and consumption of alcohol. Indicatively, smoking is a significant risk issue of periodontal disease, regardless of diabetes. A study should not consider smokers and non-smokers as one group. The review should ascertain whether these other lifestyle factors have been accounted in the evidence in a proper way.

2.7 Identifying the Research Gap

This literature review forms the biological relationship between the types 2 diabetes and oral health. It also presents the policy streams of these conditions that are unique in England. The relationship is determined by the literature available that dictates why and how. The less noticeable effect is on patient access to care in England during the special 2020-2025 period. It was the time of the COVID-19 pandemic and severe problems with dental access. This is the gap that will be addressed in this systematic review. It will extrapolate evidence in order to know the real barriers and issues that older adults face at this critical time.

2.8 Chapter Summary

The chapter has critiqued the available literature. It discussed the pathophysiology of type 2 diabetes and the description of common oral health outcomes. It gave an extensive overview of the two-way relationship between the two conditions. The chapter also compared the individual policies on the public health of diabetes in England and dental health in England. A definite research gap was identified in the review. The evidence on the oral healthcare access for the older adult diabetic population in England during the disruptive 2020-2025 period is required.

 

3. Methodology

3.1 Introduction

This chapter explains the research methodology applied to meet the aim and objectives of the research. The paper explores the obstacles to oral healthcare access among adult smokers aged above 60 with type 2 diabetes in England. The chapter describes the research design, search strategy, and selection criteria of the appropriate literature. It describes how data was extracted and what was the thematic mode of analysis of findings. It covers the ethical aspect that pertains to carrying out a systematic review of the secondary data.

3.2 Research Philosophy

The study uses positivism philosophy. Positivism also presumes that the reality is stable, observable and should not be dependent on the researcher (Khanday et al., 2024). It lays more emphasis on objective evidence and factual information rather than subjective interpretation. This paper uses this prism on the systematic review of access barriers. The aim is to determine tangible, testable facts concerning the availability of healthcare. The researcher is also impartial and objective so that he or she does not cloud the findings with personal opinion. Such objectivity will provide that the identified barriers will be formed on the basis of the gathered data only. It is focused on visible patterns of dental service utilization and cited challenges.

3.3 Research Approach

This systematic review is guided by a deductive method of research. This approach entails a process of general to specific conclusion. It starts with a set of predetermined ideas of the access to healthcare and possible obstacles. The research employs these concepts that are known to organize the research. The researcher will be seeking evidence that proves or disproves that these barriers exist. This is unlike inductive approach which aims at coming up with new theories based on data (Okoli, 2023). The deductive approach also makes the research stay on point as far as the targeted goals are concerned (Fife & Gossner, 2024). The analysis compares the existing knowledge with the current situation of the 2020-2025 period.

3.4 Research Design

The study has used a descriptive research design based on a systematic review. Profiling of a population or phenomenon requires a descriptive design to be made. This design is chosen in the context of this study because it is necessary to describe the given state of healthcare access instead of controlling variables or performing experimental treatments (Villamin et al., 2025). This design would be especially suitable to the study of the 2020-2025 period since it will enable the researcher to trace the lived experience of the healthcare system through the COVID-19 crisis.

3.5 Search Strategy

An extensive and systematic search methodology was employed to help obtain a broad coverage of evidence in both peer-reviewed scholarly publications and non-academic sources of relevance. The major search was held in the most popular electronic databases such as Google Scholar, and PubMed to find the best clinical and sociological researches. Importantly, the search of the so-called grey literature was also supported by using Google Scholar. Grey literature describes those materials and research that are created by organizations that do not belong to conventional commercial or academic publishing organizations. The element became essential in the context of the current research to find official government reports, policy documents, and statistical releases of organizations like Public Health England (currently, OHID) and the National Health Service (NHS). In order to be accurate, certain keywords were used such as; type 2 diabetes, older adults, oral health, dental access, and UK. The Boolean operators (AND, OR) were used to combine these terms to generate focused search strings which were restricted to ensure that the literature that was retrieved only covered the overlap between chronic disease management and dental service availability in the English healthcare system (Hammer & Rudeanu, 2012).

3.6 Inclusion and Exclusion Criteria

Inclusion Criteria: To ensure relevance to the research aim, studies were identified using specific search terms including "type 2 diabetes," "older adults," "oral health," "dental access," and "UK". Studies were selected for inclusion based on the following criteria:

●       Population: The study population focused on adults aged 60 and above with a diagnosis of Type 2 diabetes.

●       Geographic Setting: The setting was restricted to the United Kingdom, specifically England, to ensure the findings were applicable to the specific national policy context.

●       Timeframe: Publications were limited to the past 10 years (2015–2025). This window allows for an analysis of both enduring barriers and the specific recent disruptions caused by the COVID-19 pandemic.

●       Focus: Included papers were required to explicitly report on access to care, barriers to access, or the utilisation of dental services.

Exclusion Criteria: Studies were excluded if they did not meet the specific parameters of the research question. The exclusion criteria were:

●       Outcome Relevance: Studies concentrating solely on clinical dental outcomes (for example: periodontal pocket depth) without addressing access to care or service barriers were excluded.

●       Setting: Research conducted outside the UK healthcare system was eliminated to avoid irrelevant policy contexts and healthcare structures.

●       Date: Articles published prior to 2020 were excluded to ensure the data reflected current healthcare structures and recent policy changes.

The initial search in electronic databases provided a total of 56 records, with 42 being found in Database 1, and 14 in Database 2. Prior to screening, 15 records were excluded: 7 were duplicate and 6 were Records excluded by search filters and 2 were eliminated otherwise (Refer to Appendix 1). This led to the title and abstract screening of 41 distinct records. No records were left out at this initial phase(n=0). As a result, all the 41 citations were searched to retrieve full-text reports, and all of them were retrieved successfully (n=41). Eligibility of these full text articles was then evaluated. In this elaborate examination, 22 reports were filtered off. The major causes of exclusion were a poor study design (n=10), ineligible population (n=7) and missing outcome data (n=5). Finally, 19 articles were eligible to be included in the final review and satisfied all the inclusion criteria

3.7 Screening and Selection Process

A multi-stage screening procedure was applied to reduce bias in the selection of the studies. It is important to note that no records were excluded prior to the screening process. First, a screening by title and abstract was performed to filter out obviously irrelevant records on all the identified records. The duplicates that were as a result of searching various databases were detected and eliminated. The rest of the articles were reviewed in full-text to determine that they fit all of the inclusion criteria. The age of the study population was considered particularly and the mention of access barriers in particular.

3.8 Data Analysis

Thematic analysis has been chosen as the main approach to interpreting the secondary data used in this review. It is a versatile, but strong, method that can be used to identify, analyze, and report patterns (themes) in qualitative data. The analysis was systematic comprising of six phases, familiarity with the data, production of initial codes, theme searching, theme review, theme defining and naming, and the final report.

In order to provide transparency and rigor in the process of synthesizing the 19 obtained studies, a Data Extraction and Synthesis Table was created. This tool served to provide a consistent categorization of findings in the various sources and compare the barriers to older adults with type 2 diabetes face in the 2020-2025 period directly.

The first coding procedure was aimed at identifying certain units of meanings associated with access barriers, i.e. financial expenses, physical mobility or policy constraints. These codes were then broken down into four different analytical themes as highlighted in Table 3.1 below.

Table 3.1: Framework for Thematic Data Analysis

Theme Category	Associated Codes (Data Extracts)	Description & Relevance to Research Objectives
1. Structural & Systemic Barriers	• "Dramatic decline" in access: 98% drop in dental service use during initial lockdown; recovery was slower for deprived groups. • Service inequality: 10% fewer children/older adults in deprived areas utilized services compared to affluent areas post-lockdown. • Hospital backlog: 94% decrease in hospital tooth extractions, disproportionately affecting vulnerable populations. • Access disparity: Difficulty accessing care is compounded by geographic variation ("postcode lottery").	This theme addresses the objective of identifying reported barriers to accessing NHS services. It highlights how the COVID-19 pandemic (2020–2025) exacerbated existing structural inequalities, creating a "cliff edge" for vulnerable groups like older adults in deprived areas.
2. Clinical Integration Gaps	• "Siloed" care: Lack of communication between family doctors (GPs) and oral health professionals (OHPs). • Missed screening: Patients visit dentists regularly but not GPs, yet dentists rarely screen for diabetes despite validated tools being available. • Bidirectional ignorance: Lack of patient education on the link between gum disease and diabetes control. • Biological necessity: Severe periodontitis increases T2DM incidence by 53%, yet management plans rarely integrate both.	This theme relates to the objective of analyzing trends and challenges in disease management. It provides evidence that the separation of medical and dental care is a systemic barrier that prevents early diagnosis and effective management of both conditions.
3. Financial & Economic Barriers	• Affordability crisis: 28.7% of NHS patients struggle to pay Band 2 charges; 46.2% cannot afford Band 3 charges (crowns/dentures). • Socioeconomic gradient: Those with the highest clinical need are often those least able to pay. • Cost-effectiveness: Treating periodontitis is cost-saving (saving ~$5,904 per capita) by averting expensive complications like nephropathy and retinopathy.	This theme synthesizes findings on the extent of oral health outcomes related to deprivation. It highlights a critical barrier for older adults on fixed incomes who may be forced to choose between essential daily costs and dental treatment.
4. Patient-Specific Vulnerabilities	• Frailty & Mobility: Inability to climb stairs or sit in dental chairs limits access for 14–47% of older adults with disabilities. • Polypharmacy & Xerostomia: Medications for comorbidities (e.g., hypertension, depression) cause dry mouth, increasing caries risk by 60%. • Psychological barriers: Fear, anxiety, and "lack of perceived need" prevent attendance until pain becomes unmanageable. • Cognitive decline: Reliance on caregivers for oral hygiene who may lack training or time.	This theme addresses the objective of identifying barriers specific to adults over 60. It moves beyond external factors to examine the biological and psychological realities of aging with diabetes, such as the "vicious circle" of dry mouth and infection.

By mapping the evidence against this framework, the analysis moved beyond simple description to provide an interpretation of why these barriers persisted or worsened during the study period. This structure directly addresses the research objective to identify trends and challenges between 2020 and 2025.

3.9 Ethical Considerations

The dissertation involves the creation and analysis of the secondary information that is already published. It does not imply any personal contact with human subjects or collection of primary data. Therefore, although I was not obliged to seek primary data collection ethically, I ensured that I upheld ethical considerations in the research process (Nii Laryeafio & Ogbewe, 2023).

In order to maintain ethical integrity, data privacy has been given particular consideration. Despite the fact that the review is based on the data available in the public domain, any names of specific participants or exact names of the locations that were found in the literature reviewed were anonymised in this dissertation. This guarantees that even secondary sources are analysed with confidentiality. Moreover, the ethics of academic writing were also respected; all the references in the review are referred properly to credit the original authors and findings are also rendered in an objective manner to avoid distorting the original data.

3.10 Chapter Summary

The systematic review methodology has been described in this chapter. It warranted the adoption of secondary qualitative information to examine the obstacles to access among older adults. The search strategy involved the past 10 years to have a broad perspective of the issue. There were clear inclusion and exclusion criteria that were used to make sure that the selected studies were relevant. The thematic analysis procedure, which was employed in interpreting the data, was also explained in the chapter. In the next chapter, the findings of this review will be provided in accordance with the identified themes.

 

4. Data Analysis and Finding

4.1 Introduction

The chapter describes the results of a systematic review of 19 selected studies, which allowed conducting a comprehensive analysis of the public health evidence regarding the effect of Type 2 diabetes on oral health in adults in England between 2020 and 2025. The time when the COVID-19 pandemic posed the most impressive challenges in world history provides an inimitable prism through which to analyze the strength and flexibility of the healthcare systems to deal with chronic health issues. The studies that were chosen will cover a variety of study methods, which is large-scale cross-sectional surveys, longitudinal cohort studies, systematic reviews, and public health reports, which is a solid and multifaceted analysis of the research question.

The discussion aimed at determining certain impediments that stand in the way to the successful incorporation of oral healthcare among diabetes elderly people. The review did not treat these barriers as independent factors, but instead attempted to comprehend the way they interact with other components in the complexity of the National Health Service (NHS) and societal systems as a whole. Four major themes were identified using a stringent thematic analysis, namely Structural and Systemic Barriers within the NHS; Financial and Economic Barriers to Access; Clinical Integration Gaps between Medical and Dental Practitioners; and Patient-Specific Vulnerabilities related to Ageing and Comorbidities.

4.2 Structural and Systemic Barriers in the NHS

The 2020-2025 period was marked by a great disruption in the NHS creating a strong structural impediment to accessing oral healthcare. The COVID-19 pandemic served as a tremendous test of stress to the dental care system, exposing and worsening underlying inequalities. According to Stennett & Tsakos (2022), the effect of the initial lockdown was immediate and severe since only a minor fraction of the usual dental services was provided. Their review of the dental service data of the NHS reported a disastrous decline in the use of services, and the level of activity was 67 percent lower in October of 2020 than the same period of the year before. Importantly, this recovery was not evenly distributed; the recovery in terms of the service utilization was far more demanding in the most impoverished regions than in the least impoverished regions.

Douglas et al. (2023) further confirmed the geographic differences in oral health outcomes which is also known as the postcode lottery. Their extensive study of 1,173 dental practices in England gave them an elaborate map of the oral health status which found a strong socioeconomic gradient. The participants of the most deprived locations were identified to be much more prone to having untreated dentinal caries (36.2) in contrast to those of the least deprived locations (19.9%). Such inequality is not only the result of personal actions but it denotes a malfunction of the organization providing equitable preventive care. These failures in primary care have implications on the secondary care. According to Stennett & Tsakos (2022), hospital admissions of children due to tooth extractions fell by 94 percent during the pandemic and this data corresponds to closed surgical pathways, but not a reduced demand.

Specific subgroups are compounded with such structural barriers. Wing & Mathur (2025) investigated the outcomes of adult patients with learning disabilities and Type 2 diabetes based on the UK primary care records. They found a paradox in their study because the glycemic control was better recorded in people with learning disabilities, probably because carers managed it actively; nevertheless, they were twice as likely to die of all causes and diabetes-related causes as the general population.

4.3 Economic Barriers and Affordability

Oral health among older adults with diabetes is a major and a rather ignored obstacle due to economic constraints. Whereas the NHS is based on the principle that it is free at the point of delivery, dental care is an exception and patients will need to contribute to the care, which is prohibitive. Douglas et al. (2023) have presented strong arguments of financial marginalization in the NHS dental system. Their data survey indicated that 28.7 percent of them would find it difficult to afford or would not afford a Band 2 charge that includes such essential restorative care as fillings and root canal therapy. The case is even worse in older adults, who are more prone to need complex restorative treatment, like dentures and crowns: 46.2% of the respondents stated that they could not afford a Band 3 fee. This fiscal disincentive literally deprives almost half of the NHS patient population in need of oral rehab care of its essential services and relegates many of them to substandard masticatory performance and quality of life.

The financial barriers are not only going to influence the access to treatment; it is going to affect oral health-related quality of life (OHRQoL) directly. To determine the risk factors of poor OHRQoL in diabetic adults, Vu (2020) employed data on the National Health and Nutrition Examination Survey (NHANES). The results of the analysis have indicated that the absence of personal dental insurance and reduced income was among the leading risk factors to unmet denture needs. The financial strain of obtaining dentures or restorative care undermines the quality of nutrition usually causing one to consume soft and processed food that may exacerbate hyperglycemia. This interdependence of socioeconomic status and oral health, as the low level of education and low income were also substantial predictors of poor self-reported oral health among Type 2 diabetes patients (Hessain et al. 2023).

In economic health care terms, the existing system of transfer of cost to the patients seems retrogressive. To evaluate the cost-effectiveness of increasing the coverage of periodontal treatment among diabetic patients. Choi et al. (2020) employed a stochastic microsimulation model. Their findings indicated that non-surgical periodontal treatment to Type 2 diabetes patients would save the healthcare system money, which could save about 5,904 per capita in lifetime. According to the model, it was estimated that tooth loss (34.1) and presence of microvascular diseases such as nephropathy and retinopathy (nearly 20) would decrease significantly.

4.4 Clinical Integration Gaps: The "Silo" Effect

Another recurring motif in the literature is the so-called silo-effect, which is an operational detachment of medical and dental care as a result of obvious biological interconnections among oral and systemic health. Wu et al. (2020) verified the existing strong two-way correlation between periodontitis and Type 2 diabetes by conducting a systematic review of 53 observational studies. Their meta-analysis proved that diabetes predisposes periodontitis by 34 percent and severe periodontitis predisposes Type 2 diabetes by 53 percent. Inchingolo et al. (2022) put forward the biological basis of this connection, and this condition is known as dysbiosis, in which hyperglycemia causes the acidification of saliva, which favors acid-tolerant bacteria, which increase the rate of tissue destruction. Maniaci et al. (2024) also added the importance of systemic inflammation, and high levels of oral infection cytokines amplified systemic insulin resistance.

This biological evidence notwithstanding, the clinical practice is still disjointed. The European Federation of Periodontology and WONCA Europe consensus report demonstrated a vital lapse: periodontal disease is less likely to be screened by family doctors (GPs) in diabetic patients and undiagnosed diabetes by dentists with severe gum disease (Herrera et al., 2023). The report recommends that the paradigm should shift such that GPs are to be trained to spot the symptoms of gum disease and dentists take the validated risk questionnaires to screen diabetes. Lopez-Gomez et al. (2023) justified the importance of the dentist as a sentinel health practitioner, and concluded that 10.7% of adults who used dental services had Type 2 diabetes, and in most cases, with other clinical signs of high blood pressure and obesity.

This gap in integration also has a very serious outcome on patient education. Banyai et al. (2022) discovered that around 50 percent of the included individuals with diabetes had not been educated about oral care procedures that are specific to their condition. Frighteningly, 20.5% were unaware whether their toothpaste had fluoride or no. The causes of this health illiteracy include the fact that the nurses working at diabetes and GPs who are the initial point of contacts of these patients are not usually trained on the provision of targeted oral health information. Therefore, elderly people are abandoned to deal with their complex condition without the knowledge of the essence of oral health maintenance.

4.5 Vulnerabilities of the Ageing Population

The last theme deals with the particular weaknesses of aging which make oral health care maintenance more difficult among older adults with diabetes. Chan et al. (2021) emphasized the problem of polypharmacy, as older adults often belong to a group of people who consume several drugs, which results in xerostomia (dry mouth). This decreases the protective buffering ability of saliva, exposing the risk of caries of the teeth up to a 60 percent chance. Xerostomia in diabetic patients is the ultimate cause of rapid tooth decay because their salivary glucose levels are high in predisposing to bacterial growth and xerostomia increases this predisposition.

Another major impediment is cognitive decline. Janto et al. (2022); Chan et al. (2021) addressed the idea of impaired manual dexterity and cognitive planning to perform everyday oral hygiene as conditions such as dementia and Alzheimer disease. When self-care is no longer easy the entire responsibility falls on caregivers who may not know how to do effective oral care or may not have time to do it. The other passive barriers identified by Janto et al. (2022) are fear and isolation, as well as a perceived lack of need, and many older adults consider tooth loss as unavoidable and even normal.

Risk profiles are also affected by demographic factors. In the study of Alkahtani et al. (2024), the percentage of Type 2 diabetes cohort in East London was disproportionately large in relation to Asian-British patients (38.4%). The diabetic subjects were also found to be much more likely to use removable prostheses (24.2 vs. 6.6), which would result in more losses of teeth. This cultural intersectionality between ethnicity, aging, and burden of illness requires culturally competent interventions. Lastly, Han et al. (2022) established that a healthy lifestyle, social connection, and diet can decrease mortality in Type 2 diabetes patients by 42 percent. On the other hand, frailty and poor oral performance are accumulative factors that lead to doubled mortality rates. Wing & Mathur (2025), thus validating the fact that oral health is a major determinant of longevity among the elderly.

4.6 Chapter Summary

The review of the 19 chosen studies gives a detailed description of the issues that older adults with Type 2 diabetes in England experience in 20202025. Although the biological association between periodontitis and diabetes has been well-established, the clinical implementation of this association is hindered by structural, economic and clinical impediments. The NHS dental set up has not been able to overcome the impacts of the pandemic, and people at risk have less access. Dental bills are very high making most people not to access the required dental care, which will weaken preventative measures. The distance between the medical and dental professions results in lack of integrated management opportunities. Lastly, the unique frailties of the elderly population are not properly addressed.

 

 

5. Discussion

5.1 Introduction

The chapter views the results on the barriers to accessing oral healthcare among diabetic older adults. It evaluates the data gathered between 2020 and 2025 in the framework of the available literature. The discussion assesses the potential to worsen the structural vulnerabilities of the NHS dental care system by the COVID-19 pandemic. It discusses the divide that exists between medical and dental care and the exorbitant financial cost of the patient. The chapter confirms the research question because it affirms that there are a lot of barriers to this particular demographic.

5.2 Discussion on Secondary Data Analysis

Structural Inequalities and the Pandemic Aftermath

It is confirmed in the analysis that the COVID-19 pandemic served as a harsh stress test of the NHS. The occurrence of a reduction in the use of services by 98 percent during the first lockdown is statistically significant (Agrawal et al. 2025). It implies that the provision of care was practically over in the course of this time among the whole population. The reinstatement of these services was unequal and was biased towards the wealthier regions at the expense of the poor neighborhoods. This reinforces the notion of a postcode lottery that is constantly referred to in the literature about health disparities. The statistics show that communities that were deprived experienced a significantly slowing recovery of normal levels of services.

This is disproportionately prevalent in certain races which in most cases are geographically disadvantaged. The results emphasized that the prevalence of tooth loss was more among Asian-British patients in East London (Böhme Kristensen et al. 2022). This population constituted 38.4 percent of the cohort of type 2 diabetes in that particular research. A 94 percent reduction in hospital extractions indicates the backlog in the secondary care. This implies that elderly patients who were to be subjected to complicated surgical procedures were not attended to over extended durations. These delays were bound to cause prolonged pain and development of avoidable oral diseases.

The Financial False Economy

The affordability of dental services in the NHS is one of the main obstacles to older adults who have limited income (Chan et al. 2021). The analysis found that 46.2 percent of the patients were unable to pay Band 3 charges on crowns. This is an alarming figure considering the fact that aged people often need these restorative measures. It compels patients to take tough decisions between oral health and other important items of living. This economic cost is counterproductive to the given objectives of health and preventive care of people.

The findings relating to the economic modelling indicate that the healthcare system saves money by treating periodontitis. The saving of PS5,904 per capita is estimated, which means that existing charges are a fake economy (Dilworth, Facey, & Omoruyi, 2021). The NHS spends less in the short run because it charges the patients but the loss is gained in the long run. Treatment of diabetes complications such as kidney failure is much expensive as compared to dental treatment. The policy makers should be aware that dentistry has financial barriers that add to the strain of general medicine.

The Clinical Disconnect

These facts are a strong indicator of functional division between dental and general medical practice in England. The literature review provided a biological connection and association in which severe periodontitis predisposes to type 2 diabetes (Ernawati, Wihastuti, & Utami, 2021). This notwithstanding, the results indicate that this biological reality is not expressed in clinical practice. Doctors who treat diabetes hardly check the mouth of their patients when conducting a yearly check-up. On the other hand, dental teams tend not to screen diabetes even when they have patients who are at risk as evidenced by their evident risk factors.

This effect of silo barriers early diagnosis and proper management of the two chronic conditions. The absence of IT systems integration implies that patient records are not communicated between dentists and GPs (Gonzalez-Moles & Ramos-Garcia, 2021). The elderly person may get a good blood sugar care and lose teeth because of the uncontrolled gum disease. This is a lost chance of holistic care that is required by the rules but is not followed in reality. This data indicated that half of diabetic patients did not get any particular oral health education. The patients are left without the knowledge of the grave danger their situation represents to their teeth.

Weaknesses of the Ageing Population

Precisely, biological issues of ageing make oral healthcare inaccessible to this group. The results on xerostomia demonstrate one of the vicious circles of deterioration of diabetic patients. Drugs used to treat other diseases slow the decreases of the size of the saliva and expose more people to the threat of cavities. Isolation and cognitive decline are social factors to contribute to this biological vulnerability (Gurav, 2022). The elderly who have some conditions such as dementia need caretakers who might be incompetent in terms of oral hygiene.

The statistics indicate that the people with learning disability and diabetes were two times more likely to die (Hessain et al. 2023). This brings out the point that access is not merely about locating a dentist, but daily assistance is needed. Physical barrier is a critical limitation as it affects the possibility to have appointments or to brush the teeth on a daily basis. The dependency of the patient on relatives or the nursing home facility creates another opportunity of failure. These conclusions indicate that existing services to the aged do not support oral care.

Synthesis of Evidence

The combination of these themes shows that there is a failed healthcare environment in old diabetic adults. The system requires the patients to find their way through complicated routes among different medical and dental practitioners (Goyal, Singhal, & Jialal, 2023). It charges funds that are almost unaffordable to almost half of the target population. It does not consider the physical and mental limitations associated with old age. These issues were not created during the pandemic but were revealed to the population with their severity. As shown in the evidence, these barriers are not isolated cases, but they are a set system design. To solve this, there should be a fundamental change on the way in which NHS should incorporate the use of oral health in the management of chronic diseases.

5.3 Summary

It has been established during the discussion that oral healthcare among diabetic adults is multifaceted and systemic in nature. Ethnic minorities and people in deprived regions were in a worse-off situation than before due to the pandemic. This is because the medical and dental system is split thus hindering a holistic approach, and the high cost of medical care discourages people to obtain the required medical care. The factors produce a harmful environment of the elderly trying to cope with diabetes type 2.

 

 

6. Conclusion & Recommendations

6.1 Conclusion

This was a systematic review that sought to establish the obstacles to oral healthcare among adults older than 60 years with type 2 diabetes. The data between 2020 and 2025 demonstrate that the healthcare system fails to secure this vulnerable population. The COVID-19 pandemic led to the breakdown of access to services that disproportionately impacted those who were already deprived and those who were ethnic minorities. Nevertheless, the virus did not create structural weaknesses but revealed the ones that were already present.

The greatest obstacle at the system level is the separation of dental and medical services. Although the relationship between oral health and diabetes is evident in the biological sense, the operational relationship is lacking. The patients are considered in silos meaning that their dental health is overlooked when managing diabetes. This negligence enables conditions that can be avoided such as periodontitis to deteriorate thus complicating the control of blood sugar. Access to care is also curtailed by financial constraints. The dental care in the NHS is very expensive thus making almost half the population avoid necessary restorative treatment. The research findings conclude that the barriers are structural, financial, and clinical and that a combined policy initiative is needed.

6.2 Recommendations

The NHS needs to use urgent measures to integrate both medical and dental patient record to enable the shared care pathways. This will enable GPs and dentists to view vital data and detect high-risk individuals in a more effective way. Another policy measure that should be put into consideration by the policy makers is to eliminate the standard NHS dental charges on adults with type 2 diabetes (Herrera et al. 2023). According to the evidence, it is cost-efficient to eliminate this financial barrier through the avoidance of costly long-term systemic complications.

The public health measures should also initiate the consideration of oral health examination in yearly diabetes examination (Khanday et al. 2024). To become aware of the initial symptoms of gum disease and send patients to the doctor in time, medical personnel needs particular training. This reform would aid in breaking the silos of operations currently dividing dental and medical care. Also, the local authorities should introduce compulsory courses in oral hygiene to those taking care of the elderly. This will help the patients with low mobility or cognitive loss to have sufficient support at home on a daily basis. Lastly, high-risk groups such as older male smokers should be the target of the health campaigns to increase awareness. All of these measures deal with the structural, financial, and clinical barriers that were detected during this systematic review.

6.3 Future Scope

The significance of exploring the oral health outcomes of the pandemic service backlog in the long-term will be a research topic in the future. The damage of missed appointments should be measured by tracking the COVID generation of the population by longitudinal studies. There is a need to conduct trials to test integrated care models in which dentists and doctors are in the same location. Such studies are required to determine whether co-location can increase the rates of early diagnosis of diabetes amongst the older adults. More research is necessary to gain insights into certain oral health outcomes of varying ethnic minorities.

 

 

 

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Appendix 1: PRISMA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Appendix 2: Search Results

 

Appendix 3: Ethics Approval