Cantilever Fixed Partial Denture
Fixed partial dentures with cantilevers (CFPD) are among the treatment options for partial edentulism.
A cantilever beam by definition (Tylman, 1970), is a beam that is supported by only one fixed support at one of its ends. A direct cantilever bridge, is when the pontic is attached to an adjacent retainer.
The main indications for cantilever bridgework are situations in which:
1 . the teeth on either side of the proposed pontic that might ordinarily be used as abutments for fixed bridgework are unsuitable by reason of morphology, periodontal pathology or unfavorable angulation
2. cosmetic needs cannot be met by conventional fixed bridgework
3. the need to avoid unnecessary involvement of sound teeth is an overriding factor on grounds of pulpal risk, cosmetic implications or the temperament of the patient. (H. S. M. CRABB 1974)
Other indications for the incorporation of cantilever partial dentures encompass the need for increased chewing comfort, satisfaction of patient demands for esthetics, and properly directed occlusal forces in patients with severely reduced periodontal support.
Indications for Removable Partial Denture vs Cantilever Fixed Partial Denture for Kennedy Class I
According to Hedegârd and Landt (1983)
Cantilever Fixed Partial Denture
Medium sized remaining dentition
Good periodontal support
Removable Partial Denture
Small remaining dentition
Remaining dentition with intact teeth
Distal Extending Cantilever Cantilever Fixed Partial Denture
To provide satisfactory masticatory function and to maintain occlusal as well as neuromuscular stability, lost molar or premolar are replaced:
1. In patients wearing a complete maxillary denture, prosthetic treatment in the mandible with bridgework or a removable partial denture (RPD) may also be indicated in order to increase occlusal support and stability of the maxillary denture.
2. Maxillary arch with only up to 1st molar present
Treatment with distally extending cantilever bridges in the mandible is a favorable alternative to treatment with removable partial dentures in elderly patients with a reduced dentition. Cantilever resin-bonded fixed partial dentures are simple, non-destructive, and cost-effective restorations.
Considerations of a Double Abutting Cantilever Fixed Partial Denture:
1. Replacement of a first mandibular premolar, using the second premolar and first molar splinted as abutments.
2. Replacement of the mesial half of a mandibular molar, using the second and first premolars splinted as abutments.
Antes Law suggested the root surface area of an abutment tooth should equal or be greater than that of the tooth being replaced by a pontic.
According to C . H . Wang (1998), the cantilever FPDs require at least two abutments.
According to Cheung et al, The long-term prognosis of the single-abutment cantilever is poor.
Increasing the number of splinted abutments (up to three), can offset many of the advantages for selecting this type of fixed prosthesis
Influence of Cantilever Fixed Partial Dentures on Periodontal Health
In a study of Michael Sfeizei et al (1997), End Abutment and Cantilever Fixed Partial Dentures, display identical characteristics in the periodontally damaged dentition and do not lead to deterioration of the periodontal situation if oral hygiene is closely monitored. According to C. H. F. Hämmerle et al (2000), the radiographic bone levels at abutments of Fixed Partial Dentures with Cantilevers were stable within 3% over the observation period.
Compared to patients treated with a RPD in the mandible, patients treated with extension bridges in the mandible showed
1. better functional conditions
2. better oral hygiene
3. less caries
4. less need for dental and prosthetic treatment
Caries Incidence in cantilever resin-bonded fixed partial dentures compared to conventional removable partial dentures
Jepson et al. (2001) compared the incidence of caries two years following the restoration of lower shortened dental arches with either bilateral resin bonded bridges (fixed partial dentures, FPDs) or conventional removable partial dentures (RPDs) in a randomized control trial.
In the FPD group, the caries incidence was 14% for the non-abutment teeth and 9% for the abutment teeth. This compared to 14% for the non-abutment teeth and 60% for the abutment teeth in the RPD group.
Longitudinal studies have reported an increased incidence of caries and periodontal breakdown when removable partial dentures are worn (Budtz- Jorgensen and Isidor, 1990; Jepson et al., 2001).
Ability to Chew and Bite
Leake et al. (1994) examined oral function. A significant improvement in the ability to bite and chew was found among individuals treated with a cantilever resin-bonded fixed partial denture as opposed to a free-end saddle removable partial denture .
Lower bilateral free-end saddle removable partial dentures have a low prevalence of use, with between 30 and 50% of individuals reporting that they never or only occasionally wear their prosthesis (Jepson et al., 1995).
C . H . Wang, H . E . L ee , C . C . Wang & H . P. Chang. Methods to improve a periodontally involved terminal abutment of a cantilever fixed partial denture – a finite element stress analysis, Journal of Oral Rehabilitation 1998 25; 253–257
Edward E. Hill. Decision-Making for Treatment Planning a Cantilevered Fixed Partial Denture, Compendium November | December 2009—Volume 30, Number 9
MichaelSfeizei, Lavin Fiores-de-Jacoby, Sebastian Ciando. The Influence of End Abutment and Cantilever Fixed Partial Dentures on Periodontal Health, International Journol of Periodontics & Restorative Dentistry Volume 17, Number 4 1997
H. S. M. Crabb. A reappraisal of cantilever bridgework, Journal of Oral Xehabilitation, 1974, Volume 1, pages 3-17
C. H. F. Hämmerle, M.C. Ungerer, P. C. Fantoni, Urs Brägger, W. Bürgin, N. P. Lang. Long-Term Analysis of Biologic and Technical Aspects of Fixed Partial Dentures with Cantilevers, The International Journal of Prosthodontics Volume 13, Number 5, 2000
B. Hedegârd B, H. Landt. Cantilever Bridges or Removable Partial Dentures in Kennedy Class I Cases?, Prosthodontics Number 2 February 1983 Report 2175 Page l
E. Budtz-Jorgensen, F. Isidor. Cantilever bridges or removable partial dentures in geriatric patients: a two-year study, Journal of Oral Rehabilitation, 1987, Volume 14, pages 239-249