Dentures for dental therapists - A knowledge update. An awareness of removable prostheses and their impact on the oral tissues

By Alex Farrow-Hamblen

©123ducu/E+/Getty Images Plus

Abstract

The provision and maintenance of removable prostheses, namely partial and complete dentures, falls within the scope of practice of a general dental practitioner (GDP). This typically involves restoring form and/or function in edentate (toothless) or partially-dentate patients. Dental therapists (DTs) are likely to treat these denture-wearing patients on both a dentist's prescription and via direct access. Having a basic knowledge of the denture-making process, common complications and presentations of the denture-wearer, in terms of the hard and soft tissues, is valuable in ensuring appropriate follow-up with a GDP is made if required. Relevant to DTs in practice, the reader should appreciate how their approach to soft tissues examination, caries management, non-surgical periodontal therapy and prevention, note-keeping and/or clinical photography can be modified and used in the denture-wearing patient, all the while working within their scope of practice, skills set confidence and competencies.

Clinical relevance statement

DTs are likely to treat denture-wearing patients on both a dentist's prescription and via direct access. Having a basic knowledge of the denture-making process, common complications and presentations of the denture-wearer, in terms of the hard and soft tissues, is valuable in ensuring appropriate follow-up with a GDP is noted and made if required.

Objective statement

The reader should appreciate how their approach to soft tissues examination, caries management, non-surgical periodontal therapy and prevention, note-keeping and/or clinical photography can be modified and used in the denture-wearing patient, all the while working within their scope of practice, skills set confidence and competencies.

Introduction

The provision and maintenance of removable prostheses, namely partial and complete dentures, falls within the scope of practice of a general dental practitioner (GDP).¹ However, clinical dental technicians (CDTs) can in some cases provide complete dentures without a dentist's prescription,¹ typically, in primary care, the majority of these prostheses have and continue to be provided as part of a GDP-formulated treatment plan spanning caries management, periodontal stabilisation or in the case of edentate patients, the replacement, adjustment and maintenance of complete dentures over a number of years. Since 2013, where dental therapists (DTs) have been able to work not only within their scope of practice under GDP prescription but via direct access,² there is likely a growing trend of DTs treating patients wearing dentures, some of whom will be seen by a DT without a recent examination and denture assessment by a GDP as part of a direct access clinic.

Despite the provision of removable prostheses not falling within a DT's scope of practice,¹ there is great value for DTs in having a baseline knowledge of denture fabrication (Fig. 1), denture types and importantly, the potential impacts of denture-wear on the oral tissues, especially if a direct access patient has a denture-related complaint or question that should be referred to a GDP or if the DT is tasked with managing a denture-wearing patient as part of a GDP-DT treatment plan.

Fig. 1

A brief outline of the denture-making process

This article is not a definitive guide to removable prostheses and is not intended to encourage DTs to work outside of their scope of practice, competencies, or confidence.¹ Instead, it is hoped that this article will expand and refresh the DT's working knowledge of simple oral anatomy related to impression-making [a skill within a DT's scope of practice¹], the typical removable denture types seen in primary care and how these prostheses can impact the hard and soft oral tissues - ensuring a level of understanding of the denture-wearing patient exists across the wider clinical dental team.

The process begins with the GDP's assessment of the oral hard and soft tissues, the patient's functional and aesthetic expectations +/- previous denture-wearing experience. The first practical step centres on primary impression making; in this example, an alginate impression capturing the gross landmarks of the edentate upper arch and dentate lower arch, also known as the denture-bearing area (eg the palate and/or teeth). From this impression, a primary cast and special tray is made, allowing the GDP to make a secondary impression (Figs 1A and 1B) and thus a more accurate representation of the future denture-bearing area. On this master cast, a wax rim is fabricated as part of the registration stage - carved chairside in forming a new/matching a patient's existing occlusion, face height, tooth shade and centre lines. With this, a wax version of the denture with acrylic teeth in situ (wax trial insertion) is used to verify the patient and GDP's decisions at the registration stage (Figs 1C and 1D); the wax trial insertion is the final stage where major changes to denture fit and appearance can be made. Finally, the denture is processed and fitted (Figs 1E and 1F), typically requiring a review phase (for any occlusal adjustments) and reinforcement of denture hygiene +/- general oral hygiene instruction which are typically delivered at fit. In the case of an upper complete denture (Fig. 1E), the prosthesis typically covers the entire palate and extends into the sulci (termed the denture flange). In the case of a lower partial denture, the prosthesis replaces missing teeth in a saddle (tooth-free) area and extends over the residual ridge (named the fitting surface); the teeth adjacent to the denture are known as denture abutment teeth (Fig. 1D). In some cases, these teeth are engaged by metal clasps to maximise the stability and retention (fit) of the denture.

The impact of a denture on the periodontium and soft tissues

It is well-reported within the dental literature that partial dentures can have an impact on the periodontium as risk factors for compromised plaque control, gingival inflammation and eventual clinical attachment loss.^3,4 With plaque control a key risk factor in periodontal disease,⁴ when making dentures, this can be mitigated by the GDP during the denture design phase via the use of acrylic relief (breathing space) around the gingival margins of select teeth (minimising plaque accumulation) or post-denture delivery in terms of denture hygiene instructions (daily cleaning and leaving the denture out at night). This knowledge is of importance to DTs as partial denture patients are often referred from GDPs for periodontal maintenance (Figs 2 and 3).

Fig. 2

An example of a denture case that could span the GDP-DT partnership

Fig. 3

An example of a denture case that could span the GDP-DT partnership

With respect to the oral soft tissues of the edentate patient, with reference to the palate and those with a history of an ageing prosthesis, poor plaque control and/or a complete denture which is regularly worn at night, these patients are at an increased risk of denture-induced stomatitis (DIS): an inflammatory response typically characterised by asymptomatic erythema and associated candida infection following the gross outline of the existing upper denture.⁵ If, on soft tissue examination by a DT,¹ DIS is suspected, a sensible course of action would be referral to a dentist for follow-up +/- A record of these tissues should be made by use of a clinical photograph. The first line treatment for DIS is an improvement in denture hygiene and, if unresponsive, consideration of an anti-fungal therapy at the discretion of the patient's GDP following a period of review.⁶ It follows that any unusual symptomatic or asymptomatic presentation of the soft tissues in terms of DIS, erythema or suspected denture-trauma (rubbing linked to a mobile denture, a sharp flange within the sulcus or a damaged denture fitting-surface), is to record one's observations in the clinical notes,¹ inform the patient of these findings, give a provisional diagnosis or possible cause (only if confident in doing so) and arrange an appropriate course of follow-up with a GDP.

Following multiple extractions (Fig. 3) in the upper arch due to severe and symptomatic toothwear, a same-day (immediate) denture was fitted, retaining the 16 and 15 as denture abutments. Note the accumulation of plaque at the gingival margins of the 43 and 33, also noting evidence of staining/calculus accumulation at the 33 and 32 (later removed during the fit appointment). A diabetic patient, with a new periodontal risk factor in terms of a denture in the upper and lower arch, the value of recording appropriate periodontal indices, professional mechanical plaque removal, appropriate subgingival instrumentation, oral hygiene instruction and advice RE: plasma glucose control and its link to periodontal risk⁴ can be delivered by a DT in support of the GDP's treatment plan and advice of daily denture cleaning with warm soap water, avoiding abrasive products and bleaching agents and leaving the dentures out at night. This is an example of how both DT and dentist can support and reinforce the other's advice while maintaining the periodontium and thus, the long-term success and fit of the denture.

The impact of a denture on the hard tissues

The oral hard tissues typically refer to the teeth (dentition) or the alveolus (bone). Similar to periodontal risk, partial dentures can have a damaging impact on the teeth, with plaque control a key risk factor in the caries process.⁷ Again, if via direct access or on a GDP's prescription, denture patients seen by a DT for direct restoration of the permanent dentition¹ can be considered at an increased risk of caries development and should be supported in the preventive guidance of Delivering better oral health;⁸ the dentist-DT partnership considering NaF toothpaste (on a GDP's prescription), a reduced recall interval or regular application of topical fluoride to abutment teeth/exposed root surfaces within the ageing cohort as seen fit.⁸

In the edentate patient, the gradual remodelling and loss of the underlying alveolus with time (resorption) corresponds with an inevitable loss of denture fit, noting denture mobility on function or at rest. Again, if for example, a patient attends via direct access, complaining of a loose upper complete denture to the DT (Fig. 1), the DT's scope of practice, in terms of denture provision, would likely be unknown to the patient on presentation. In this example, a brief discussion detailing the DT's scope of practice,¹ while noting a brief history of the patient's denture complaint and a clinical examination within their competence within the clinical notes,¹ is good practice and is of use to the GDP to whom the patient would be referred to for opinion +/- treatment as appropriate.

Another case (Fig. 3) details the failure of a two-wing resin-bonded bridge (previously replacing 11) and recent XLA of 22, prior to the provision of a definitive upper partial denture and periodontal stabilisation. Note erythema of the underlying soft tissue below the failed resin-bonded bridge (RBB) and marginal bleeding at 13 and 12 due to excess cement and out-dated wing design encroaching on the periodontal tissues. Also note erythema at the 22 saddle (space) area, a provisional RPD initially compromising plaque control in this region following XLA of the 22. This is a classic case that could span the surgery of a GDP-DT, beginning with clinical examination and a BPE with the GDP. In this case, a sensible periodontal treatment plan which may be referred to the DT would likely centre on OHI/PMPR (in support of the GDP's denture hygiene advice), also considering the application of topical fluoride on abutment teeth having noted early and historic demineralisation at the 21 - distal and 22 - mesial. With the support of the DT team, and a return to clinical gingival health, a stabilising periodontium and good oral hygiene habits are essential before the provision of a definitive denture. Interestingly, if such a patient was seen by a DT on a direct access clinic, prior to a dentist's assessment, having the confidence to record these soft and hard tissues findings in the written notes¹ but also, taking an intraoral photographic record¹ is an example of good practice. The use of dental photography across the GDP-DT partnership not only has value in supporting a diagnosis and/or treatment plan, but, pre-operative and post-treatment photographs offer a means of portfolio/practice-building for both the GDP and DT in highlighting collaboration, teamwork and positive patient outcomes across the clinical dental team.

Summary

When working as a DT, it can be easy to be 'put off' or feel challenged when treating denture-wearers as the provision of dentures falls outside of a DT's scope of practice,¹ especially if said patients present on a direct access clinic or to a newly-qualified DT. However, it is hoped that this article has given the reader a basic introduction or refresher to removable prostheses in terms of a working knowledge of denture fabrication, risk factors to compromised plaque control and working within one's skills set and competency in recording changes in the hard and soft tissues related to denture-wear; importantly, recognising when onward referral to a GDP is appropriate. As an aside, it is hoped that this article's discussion of potential GDP-DT denture cases, with close reference to the value of clinical photography, may spark conversation and interest in photography as a tool in expanding a DT's individual or collaborative portfolio: an opportunity to boost job satisfaction and career prospects in both a clinical or academic environment while widening the DT's skills set¹ - a skill that should be encouraged within a progressive professional that champions the value and competencies of the DT workforce.

Ethical standards statement

There are no conflicts of interest. Patient consent gained for use of photographs for editorial purposes.

CPD questions

This article has four CPD questions attached to it which will earn you one hour of verifiable CPD. To access the free BDA CPD hub, go to https://cpd.bda.org/login/index.php

Author information

Alex graduated with a Bachelor of Science Degree in Human Physiology (University of Leeds) before beginning his dental training at the University of Central Lancashire's School of Medicine and Dentistry in 2016, his training on the BDS degree running alongside UCLan's Dental Hygiene and Therapy programme. Alex successfully completed his dental training at Carlisle Dental Education Centre in 2020 before working as an NHS dentist in the Wirral for the last 1.5 years, having a particular interest in knowledge transfer and clinical communication between patients and the dental team, oral medicine and the provision of removable prostheses within an NHS primary care setting.