of the existing denture, which is short by at least 15 mm. It is also possible to see the limited degree to which the denture base wraps around the tuberosities. Both of these features will significantly compromise the stability and retention, and perpetuate the gag reflex. A thin band of tissue exists along the crest of the ridge from incisor to premolar on the patient's right-hand side, and this should be accounted for in the working impression; in order to avoid the denture ‘nipping’ the tissues, the impression should be taken in zinc oxide eugenol, and the borders of the thin tissue ridge should be filleted away with a scalpel. Once again, the labial portion of the anterior ridge presents with a significant undercut and it is worth considering at the assessment stage whether a defined path of insertion is possible, or whether the permanent base should be modified with permanent soft liner to allow the ridge to be atraumatically engaged.
Lower edentulous ridges
Photograph 4
The full DBA can be palpated without any pain, although contact with the posterior lateral borders of the tongue elicits a gag reflex. The ridge is atrophic with a knife edge presentation (Class IV). A thin fibrous band of tissue runs along the entire crest of the ridge – and this should be accounted for in the working impression; in order to avoid the denture ‘nipping’ the tissues, the impression should be taken in zinc oxide eugenol, and the borders of the thin tissue ridge should be filleted away with a scalpel. Muscle attachments are low and there is only a moderate sulcal depth anteriorly when the lip is retracted. The tray will need to be carefully adjusted here to ensure it is not overextended.
Photograph 5
The full DBA can be palpated here without eliciting pain or a gag reflex. The tissues are fibrous anteriorly, and it is possible to see the folds of tissue in the photograph. The ridge is atrophic (Class V) but presents with an identifiable fibrous crest. This is thicker than in photograph 4, and so is unlikely to fold over when the denture is seated. No special interventions are required in that regard. There is little identifiable sulcus anteriorly and so the tray will need to be carefully adjusted here – and it may even be the case that a purposefully mucostatic or mucocompressive impression (depending on the assessment) is taken to account for the anterior fibrous tissue. Ulceration is visible in the buccal and labial sulci, and it is important to ensure that this is resolved prior to working impressions.
Photograph 6
The full DBA can be palpated without pain or gagging. The ridge is firm, well formed and generally rounded at the crest – although there are undercut aspects around the buccal aspect. This would be graded as Class IV. Muscle attachments are relatively low and there appears to be a reasonable depth to the labial sulcus. Avoid thinking that these cases are straightforward to treat – it is sometimes the case with well-formed ridges that they pose problems in terms of ridge pain after fitting of the dentures.
6 Patient assessment for partial dentures
An assessment for a partial prosthesis begins in much the same way as for a complete denture – why does the patient want the treatment, and what are the risk factors that can alter your chances of success? The main obvious difference, however, is the presence of standing natural teeth. The health and prognosis for these teeth must be adequately assessed in order to plan the treatment effectively for removable partial prostheses – and whilst the method of partial denture design will be covered later, the necessary clinical information and indices will be mentioned here as part of the initial assessment stage.
The patient and the rationale for treatment
Why does the patient want new or improved dentures?
Do the current dentures cause pain?
Is there any difficulty chewing or speaking?
Are the dentures of a satisfactory appearance?
Prosthodontic history
What type of denture is the patient currently wearing?
How old is the prosthesis and where was it/they made?
For how many years has the patient been wearing partial dentures?
How many prostheses has the patient received before?
Is the patient willing to attend for the necessary appointments, including review appointments?
Clinical examination
Before considering removable partial prostheses, it is important to carry out a full and comprehensive extra- and intraoral assessment. The following aspects can then be considered.
Intraoral access – Can the denture-bearing anatomy be palpated easily, and can any existing prostheses be easily inserted and removed from the mouth?
Plaque control – Wearing removable partial dentures in the presence of poor plaque control poses a significant risk to the dentition, for the progression of root caries and soft tissue disease. If the basic periodontal examination (BPE) codes are anything but 0, you should be carrying out at least a plaque score and providing tailored oral hygiene instruction.
Tooth mobility and periodontal pocket depths – Whether teeth are pathologically mobile or present with deep bleeding pockets is often overlooked during a partial denture assessment. It is often assumed that the expected future loss of teeth warrants an acrylic partial denture – in reality, it is important to determine which teeth might be capable of helping to support a removable partial denture down their long axis, and use them accordingly. Teeth may also present with mobility because of occlusal trauma, especially if there is a lack of posterior support. This is unlikely to improve without the provision of a removable prosthesis to replace posterior units.
Gag reflex – Can the denture-bearing area and connector sites be palpated without eliciting a gag reflex? If not, where are the trigger zones? These are most often the dorsum of the tongue, or the posterior palate.
Ulceration – Are there any existing signs of ulceration, and do they correspond to the extensions of a prosthesis?
Temporomandibular disorder – Are there currently any signs of muscle pain or temporomandibular joint derangement?
Dry mouth – Does the patient complain of a dry mouth? Is this medication-induced? A dry mouth will significantly increase the risk of root caries and gingivitis when wearing a partial denture.
Retained roots – Could these be retained as overdenture abutments and what is the space between root surface and opposing tooth? Do not forget that healthy retained roots will prevent alveolar resorption, improve proprioception and chewing ability. Further, there
