Pjetursson BE, Tan WC, Tan K, Brägger U, Zwahlen M, Lang NP A systematic review of the survival and complication rates of resin-bonded bridges after an observation period of at least 5 years. Clin Oral Implants Res. 2008; 19:131-141 https://doi.org/10.1111/j.1600-0501.2007.01527.x
King PA, Foster LV, Yates RJ, Newcombe RG, Garrett MJ Survival characteristics of 771 resin-retained bridges provided at a UK dental teaching hospital. Br Dent J. 2015; 218:423-428 https://doi.org/10.1038/sj.bdj.2015.250
Davis DM, Fiske J, Scott B, Radford DR The emotional effects of tooth loss in a group of partially dentate people: a quantitative study. Eur J Prosthodont Rest Dent. 2001; 188:53-57 https://doi.org/10.1038/sj.bdj.4800522
Wassell RW, St George G, Ingledew RP, Steele JG Crowns and other extra-coronal restorations: provisional restorations. Br Dent J. 2002; 192:619-622 https://doi.org/10.1038/sj.bdj.4801443
Oosterkamp BC, Dijkstra PU, Remmelink HJ, van Oort RP, Sandham A Orthodontic space closure versus prosthetic replacement of missing upper lateral incisors in patients with bilateral cleft lip and palate. Cleft Palate Craniofac J. 2010; 47:591-596 https://doi.org/10.1597/09-092
Dudding T, Martin S, Popat S An introduction to the UK care pathway for children born with a cleft of the lip and/or palate. Br Dent J. 2023; 234:943-946 https://doi.org/10.1038/s41415-023-5998-z
Diangelis AJ, Andreasen JO, Ebeleseder KA International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations of permanent teeth. Dent Traumatol. 2012; 28:2-12
Andersson L, Andreasen JO, Day P, Heithersay G International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 2. Avulsion of permanent teeth. Dent Traumatol. 2012; 28:88-96 https://doi.org/10.1111/j.1600-9657.2012.01125.x
Srinivas B, Das P, Rana MM, Qureshi AQ, Vaidya KC, Ahmed Raziuddin SJ Wound healing and bone regeneration in postextraction sockets with and without platelet-rich fibrin. Ann Maxillofac Surg. 2018; 8:28-34 https://doi.org/10.4103/ams.ams_153_17
Craddock HL, Youngson CC, Manogue M, Blance A Occlusal changes following posterior tooth loss in adults. Part 2. Clinical parameters associated with movement of teeth adjacent to the site of posterior tooth loss. J Prosthodont. 2007; 16:495-501 https://doi.org/10.1111/j.1532-849X.2007.00223.x
Poyser NJ, Porter RW, Briggs PF, Chana HS, Kelleher MG The Dahl Concept: past, present and future. Br Dent J. 2005; 198:669-676 https://doi.org/10.1038/sj.bdj.4812371
Rinchuse DJ, Miles PG, Sheridan JJ Orthodontic retention and stability: a clinical perspective. J Clin Orthod. 2007; 41:125-132
Collins JM, Witcher TP, Jones VS, Noar JH, Naini FB An alternative retainer design for cleft patients: the ‘aesthetic’ retainer. Cleft Palate Craniofac J. 2010; 47:597-599 https://doi.org/10.1597/09-228
Patil BC., Jha A Retention protocol following post-orthodontic treatment in cleft palate patients – a review. J Contemp Orthod. 2022; 6:79-84 https://doi.org/10.18231/j.jco.2022.015
Dhole P, Maheshwari D Two-phase orthodontic treatment in a unilateral cleft lip and palate patient with 1-year follow-up results. APOS Trends Orthod. 2017; 7:101-107 https://doi.org/10.4103/apos.apos_5_17
Gill DS, Naini FB, Jones A, Tredwin CJ Part-time versus full-time retainer wear following fixed appliance therapy: a randomized prospective controlled trial. World J Orthod. 2007; 8:300-306
Shaha M, Varghese R, Atassi M Understanding the impact of removable partial dentures on patients' lives and their attitudes to oral care. Br Dent J. 2021; https://doi.org/10.1038/s41415-021-2949-4
Leven AJ, Preston AJ Conservative prosthetic rehabilitation of medication-related osteonecrosis of the jaw (MRONJ). Dent Update. 2016; 43:939-942 https://doi.org/10.12968/denu.2016.43.10.939
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Kermanshah H, Motevasselian F Immediate tooth replacement using fiber-reinforced composite and natural tooth pontic. Oper Dent. 2010; 35:238-245 https://doi.org/10.2341/09-136-S
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Resin-bonded bridges or resin-retained bridges (RRBs) are considered acceptable fixed prostheses for single-unit spaces in the aesthetic zone, often resulting from hypodontia or trauma. They may be used as medium-to long-term treatment options and can precede implant placement for young patients. Provisional tooth replacement before this treatment modality is not always thought to be necessary, but is often seen as appropriate. This article explores the various provisional options for single/multiple tooth space scenarios, their functional and aesthetic considerations, the risks and benefits, alongside their possible impact on the final restoration.
CPD/Clinical Relevance: Various techniques available to provisionalize RRBs to aid in RRB case planning are described.
Article
Resin-bonded bridges or resin-retained bridges (RRBs) are prostheses that require no or minimal preparation and rely on the bonding of a metal or ceramic wing to a tooth through resin cements. Developed from Rochette bridges, which have perforated metal wings to create retention, then Maryland bridges when electrochemical etching of metal allowed non-perforated wings to be used, their success rates have increased to nearly that of conventional bridge work.1,2 Now bridges constructed from zirconia are being incorporated into dental practice.
King et al reported on the survival of resin-retained bridgework, stating the highest survival rates were in single cantilever resin-bonded bridges clear of heavy occlusal force with stable abutments.3 However, they noted that where orthodontic treatment has preceded bridgework in hypodontia patients, double abutments have a much higher survival rates.
Therefore, case selection and planning are highly important for such restorations, and should take into consideration: the number of missing teeth; the quality of the abutments; prior treatment; the patient's aesthetic/functional demands (such as gingival profile, smile line, static and dynamic occlusion); and any subsequent treatment plans.
These bridges often require no preparation, but an accurate impression or digital scan of the fit surface of the abutment tooth as well as an occlusal record and design of the bridge shape and shade are needed.1 There is a period of commonly 10 days to 2 weeks in which the dental laboratory will construct the RRB. The bridge is then cemented using a resin cement, provided it is well fitting and acceptable to both the patient and clinician. Where the bridge does not fit as expected, or is aesthetically unacceptable, then the length of time for which the patient will have an edentulous space may be longer than is desirable.
Often, bridges are provided following a course of orthodontic treatment where a hypodontia space is opened up, or following tooth loss as a result of trauma or disease where bony remodelling is required before definitive restoration placement. These scenarios may result in a patient having an edentulous space for a prolonged period of time which, in the aesthetic zone especially, is not often acceptable and can affect a patient's mental health and quality of life.4 With the emergence of social media, this is increasingly unacceptable in the cosmetically focused world we live in. It therefore falls to the clinician to determine how to address this space provisionally to avoid a reduction in the patient's quality of life.
Generally, a provisional provides the patient with an interim restoration to maintain comfort and tooth vitality, avoid unwanted tooth movements, maintain a stable occlusion, ensure continued function, aid in definitive treatment planning, facilitate gingival health and contour, and, not least, maintain acceptable aesthetics.5
Provisional restorations for crowns or conventional bridgework are often thought of as temporary chairside-made or pre-formed restorations that are retained with a temporary luting cement and often mimic the final restoration. However, where resin-retained restorations do not have retentive features to facilitate this, alternative ways of provisionalizing are required.
In some cases, where temporary tooth coverage is not a driving factor for a provisional and where the patient is not concerned about the edentulous space, a decision to leave the space may be taken. Where the appearance is of concern, or previous orthodontic treatment requires space maintenance or retention, then the options for a provisional are varied.
The types of provisional available are discussed later in this article. First, cases are examined where an RRB may be appropriate and why a provisional may be used in planning.
Hypodontia
Resin-retained bridges are commonly used to replace congenitally missing teeth. Their use is appropriate in the replacement of single or multiple missing laterals and sometimes premolars, or where cleft lip and palate prevents development or eruption of single teeth.6 It is less common to use RRBs in severe hypodontia, where partial denture provision may be the treatment of choice until implants can be placed.7
Where space closure may be complex or inappropriate following orthodontics because of the degree of spacing, incisal classification, molar relationship, position/size/shape of the maxillary canine or facial profile, then prosthetic tooth replacement is carried out to fill the space.
Implants for mild hypodontia are not necessarily available on the NHS and, often, because treatment is completed during adolescence, there is a period of time where patients are ineligible/unable to have implants but require tooth replacement. RRBs bridge this gap for these patients.
For cleft lip and palate patients, the pathway to improved dental outcomes and quality of life can be long, extending from childhood into adulthood.8 Definitive restorations may not be placed until well into adulthood, and implant placement may not be appropriate for many years if at all.
The aesthetic demands of young adults and adolescents can be high, and few would be content attending school or social situations with anterior missing teeth. A provisional is therefore used in these cases to maintain the aesthetics in the anterior zone while other treatment is carried out or the patient finishes growing.
Alongside this, provisionals act to maintain the space created by orthodontic treatment, provide retention and can help the clinician and patient trial the appearance of the definitive restoration.
Trauma
Trauma, such as avulsion, severe luxation injuries, complicated enamel–dentine fracture or certain root fractures, can result in single anterior tooth loss. This can occur either at the time of trauma, or at a later date owing to the failure of initial treatment resulting in infection or root resorption, particularly in mature teeth.9
Prompt and appropriate management of these cases can prevent or postpone loss; however, treatment can still fail and, in some cases, be inappropriate or contraindicated, such as replanting carious or periodontally involved teeth, or in immunocompromised patients.10
Although in many cases the gold standard for replacement is an implant, this too has a lifespan. So, where there are financial contraindications or the trauma occurs at a young age, other options such as an RRB can be considered.
Between loss and subsequent definitive replacement of the tooth, gingival and bony changes occur during healing, resulting in ridge height and width changes of up to 4.5 mm over 3 months.11
With a provisional in situ, aesthetics are maintained in the anterior zone while allowing for adequate healing and stability of the surrounding tissues.
Disease
Tooth loss also occurs through caries or periodontal disease. The clinician often faces larger, edentulous spaces with compromised or heavily restored abutment teeth, and active periodontal disease with significant bone loss. Such cases may be inappropriate for RRB placement, leaving fewer cases where this treatment is the modality of choice.1
However, single loss of compromised premolar teeth may be one such scenario where an RRB is appropriate and provisional replacement before the final restoration allows the clinician and patient to stabilize any existing disease and allow any changes in diet and oral hygiene to occur.
Should the crown of the tooth remain intact, the provisional can incorporate, or be modelled on, the natural tooth.
Other circumstances may arise where an RRB is an appropriate choice and this must be, like all dental treatment, be planned on a case-by-case basis.
Table 1 summarizes the use of RRBs and the benefits of provisionals.
Reason for RBB use
Benefits of a provisional
Hypodontia
Lateral incisor(s) missing
Aesthetics in anterior zone
Space maintenance
Orthodontic retention
Prevent tilting of teeth
Trial final restoration
Premolar(s) missing
Cleft lip/palate resulting in lack of development or uneruption of teeth
The type of provisional restoration or appliance chosen will depend on the case and the treatment that has preceded or is to follow. Some of the options for provisionals are outlined.
Leave a space
One must consider all treatment options when planning a case, including the option of no treatment.
Where there are no requirements for a provisional, then leaving the space may be appropriate. This reduces steps and eliminates costs for the clinician, laboratory and often the patient. It avoids damage to the tooth in removing a provisional RRB, which, where there has been no preparation, is particularly undesirable. Leaving the space however, may risk minor tooth movements, such as tilting, resulting in space loss and a poorer fitting final restoration.12
Occlusal adjustment or palatal reduction may be futile in minimal-preparation RRBs, if with no provisional, relative axial tooth movement as described by Dahl et al, brings the tooth into occlusion.13
Without a provisional, socket preservation to guide soft tissue contour may not be possible and future soft tissue surgery may be indicated to improve this.14
Finally, the clinician and patient are unable to trial the final restoration for aesthetics.
For hypodontia patients, the need for orthodontic retention and space maintenance, along with the aesthetic demands of this age group of patients, mean this option is usually inappropriate.
Where a patient does not want a short-term replacement following a tooth extraction and consents regarding the risks, leaving a space will be appropriate.
Vacuum-formed retainer
After orthodontic treatment, a vacuum-formed clear retainer, such as an Essix (Dentsply Sirona, Charlotte, NC, USA) retainer, is commonly provided for retention.15 These can be worn during the day or night.
Where a hypodontia patient has had a space opened, (s)he can be fitted with a prosthetic tooth in the interim. These are often acceptable in young and adolescent patients who have recently completed orthodontic treatment. They are relatively inexpensive, and quick and simple to construct, often allowing same-day delivery.15
They are often comfortable, affect speech minimally during wear and the clear material used makes them discreet. During their use as a provisional, they can also be used as a bleaching tray to provide the desired tooth shade before definitive restoration.15 In cases where an RRB may debond, they could act as a fail-safe before it can be refitted, provided tooth movements have not occurred.
On the downside, issues may arise when eating, as the retainer needs to be removed, thus exposing the edentulous space, something that many adolescents or young adults may not be comfortable with during school or at work. Patients may not be comfortable wearing this appliance for some time, such as the 3–6-month healing time required for bony remodelling after extraction.
Finally, Collins et al found that these retainers did not maintain the edentulous space effectively, and therefore could have an adverse effect on the definitive RRB.16
The author proposes that minor tooth movements could occur with fit of a new retainer and therefore it may be important to have this made and worn for several weeks before designing the definitive RRB to avoid a poor final fit.
Hawley retainer
A Hawley retainer can form part of a patient's orthodontic treatment plan. It can be designed to include a provisional tooth at minimal further cost and time.17 It is beneficial in that the appliance can maintain space, move teeth and allow a trial pontic design. Figure 1 shows a Hawley retainer with a pontic replacing the left lateral incisor in a patient with a cleft palate.18
Figure 1. Hawley retainer with pontic replacing left lateral incisor in cleft palate patient.18
Pink acrylic can be added to the pontic to mimic the adjacent gingival profile and fill any spaces that result from bone loss, such as that in a patient with a cleft lip and palate, as described in the case report by Dhole and Maheshwari.18 It is also very effective in maintaining arch expansion, which is commonly required during orthodontic treatment in this group of patients.19
As with a partial denture, patients are able to leave the appliance in situ when eating. However, they may find an issue where it covers the palate and can result in a gag reflex. Also, aesthetics and comfort can be compromised with bulky metal and acrylic.
Removable partial denture
A removable partial denture (RPD) is often considered a definitive treatment option for older patients with multiple missing teeth. This article proposes its use as a provisional to bridgework.
For a patient undergoing a treatment plan involving loss of multiple teeth due to disease, requiring stabilization of their oral hygiene, diet and subsequently disease, an immediate RPD could be considered to replace teeth in the aesthetic zone. This is more likely to be considered in adult patients, many of whom may be dissatisfied or not accepting of a partial denture, particularly younger individuals.20
An RPD may be contraindicated after extraction in patients at risk of medication-related osteonecrosis of the jaw, as mucosal forces from the denture can lead to this.21 A tooth-borne cobalt chrome RPD reduces this risk owing to its tooth-borne element, but its higher financial cost makes it a poor choice for a provisional restoration.
RPDs may be unacceptable to patients owing to their palatal coverage, especially for those with high gag reflexes and, financially, they will increase the cost of the overall treatment plan. Additionally, retention may be low, resulting in movement or dropping, reducing function. However, patients may prefer as an interim appliance to some retainer options because removal is not required for eating and drinking.
Use of the natural tooth
Where a tooth requires extraction but the crown remains intact, the natural crown may be used in temporizing the space. A natural tooth provides accurate colour, size and shape and avoids delays in construction of an appliance.22 This could be a viable option for patients who are young and still growing, have high concerns about aesthetics or need to avoid changes to their embouchure as part of their profession as singers or wind musicians.
A metal framework (or zirconia or lithium disilicate where aesthetic demands are high) can be created to fit the palatal surface of the pontic and its abutment prior to extraction, with the provisional subsequently fitted on the day of tooth loss. Alternatively, titanium wire, metal mesh or fibre-reinforced composite can be used to splint the crown to its adjacent teeth in emergency situations.23,24
The benefit is that the patient's natural aesthetics are maintained. For example in periodontal patients, the crown can be sectioned on the root surface to mimic recession on the adjacent teeth.
Use of the natural tooth requires removal of its pulpal tissue and replacement with composite or glass ionomer restorative material, so adequate preparation time is required.25 Despite this, it still has the potential to discolour, and is also at risk of caries.
Good bonding of this type of restoration requires adequate tooth surface area, a sandblasted, acid-etched metal surface (or silanated ceramic surface) and a resin cement. However, this could result in difficult removal when the restoration needs to be replaced, so considerations of Rochette-style metal frameworks are appropriate.
In cases where the natural tooth is not viable for use as an immediate provisional, consideration could be given to using an acid-etched denture tooth, using the same pre-made metal/ceramic framework or fibre-reinforced composite. In practice, though, laboratory costs may be a barrier to this type of provisional.
Figure 2 shows a composite splinted natural tooth bridge with a single cantilever design in a periodontal patient.
Figure 2.
(a,b) Composite splinted natural tooth bridge, single cantilever design in a periodontal patient. Photograph of natural tooth replacement: LR1 bonded to LR2 in a single cantilever design using composite.
Rochette bridge
Where the natural crown of the tooth is not viable for use, a conventional Rochette bridge could be constructed for use as a provisional and cemented with a resin-modified glass ionomer cement.
A Rochette bridge incorporates perforations in the metal framework, which were initially thought to create retention for cements to lock into (Figure 3). However, more recently, with the emergence of resin cements that create a strong bond to the tooth, this design is now seen to reduce retention because there is less surface area for bonding. Now, these bridges are commonly used for provisionals before implant placement where space maintenance is required and they can have a high survival rate of 80% over 200 days.26
Figure 3. Rochette bridge.
Its use as a provisional is acceptable because it is easier to remove than a conventional metal framework. The perforations in the metal wing reduce bond strength. Another benefit is that it avoids palatal coverage, unlike a partial denture or Hawley retainer. It also allows the clinician to trial aesthetics, shade and design as well as contouring the soft tissues before the final restoration.
This restoration may be inappropriate for use in people with a high smile line because any loss in ridge height can leave space beneath the pontic. Furthermore, if there are heavy occlusal forces on abutment teeth, debonding may result. In these cases, a spring cantilever design from a non-adjacent tooth could be considered.26
Implant placement could succeed in any of the options given for provisionalizing a space. Many may consider a no-preparation RRB itself, a provisional to implant placement in a young patient.
Conclusion
This article highlights an inexhaustive range of options available to provisionalize an RRB. It is evident in any treatment planning that an individual approach should be taken; what may be appropriate for one patient may not be for another.
The decisions made will depend on patient factors, such as their age, appearance, smile line, occlusion, professional and aesthetic demands, as well as tooth factors such as the cause of tooth loss, bone levels, disease, quality of adjacent teeth and longer-term plans for replacement.
A paucity of research exists on the pros and cons of provisional restorations on the final RRB, and a detailed investigation would help clinicians with planning.
