Longevity of treatment options for partially edentulous patients

TREATMENT FOR
PARTIALLY EDENTULOUS
PATIENTS
BY: BELAL NABIL MOUSTAFA ELMARHOUMY.

LECTURE OUTLINE:
• Introduction.
• Removable partial denture : 1) classification.
• 2) treatment plan.
• 3) longevity.
• Fixed partial denture: 1) classification.
• 2) treatment plan.
• 3) longevity.
• References.

INTRODUCTION:
• In many countries a major part of the population has an incomplete but still
functional dentition.
• A substantial number of these edentulous portions of the dental arch are not
prosthetically restored, and many patients are functioning with a shortened
dental arch without any need for treatment.
• Nevertheless, restoring oral function and appearance is often necessary; there is a
particularly higher percentage of replacements especially in higher economic
groups.

REMOVABLE PARTIAL DENTURE:
1) CLASSIFICATION:
• Kennedy classification:
• Class 1: Bilateral edentulous areas posterior to
natural teeth.
• Class 2: Unilateral edentulous area posterior to
natural teeth.
• Class 3: Unilateral edentulous area bounded by
teeth anteriorly and posteriorly.
• Class 4: Single bilateral (crosses midline)
anterior to remaining teeth.

RULES GOVERNING APPLICATION OF KENNEDY METHOD
• Rule 1: classification should follow any extractions of teeth might alter the original classification.
• Rule 2: if third molar or second is missing or not to be replaced, not considered in the classification.
• Rule 3: if third molar or second molar is to be used an abutment, considered in the classification.
• Rule 4: the most posterior area determines the classification.
• Rule 5: edentulous areas other than those determine the classification referred to as modifications and
are designated by their number only (the extent is not considered) . E.g.: class2 mod2
• Rule 6: no modification in class 4 arches.

2) TREATMENT PLAN
• Objectives of treatment plan:
• 1) Support.
• 2) Retention.
• 3) Stability.

A) RPD SUPPORT:
• There are two types of support: tissue supported, as in (class1 and class 2)
• tooth-tissue supported, as in (class3 and class4)
• RDP components contribute to the support:
• 1) Major connectors: provides cross-arch stability to help resist displacement by functional stress and
contribute to the support of the prosthesis.
• 2) Rests: serve to support the position of a partial denture and to resist movement toward the tissue.

MAJOR CONNECTORS:
• Lower major connectors:
• Lingual bar.
• Linguoplate.
• Sublingual bar.
• Lingual bar with cingulum bar (double lingual bar).
• Cingulum bar.
• Labial bar.

• Upper major connectors:
• Single palatal strap.
• Single palatal bar.
• Anterior and posterior palatal strap.
• Anterior posterior palatal bar.
• Palatal plate.
• Palatal linguoplate.

• Rests : main purpose to provide vertical support for the partial denture.
• Occlusal rest.
• Incisal rest.
• Lingual rests.
• Embrasure hook.

B) RPD RETENTION:
• Retention of RDP is achieved by two components: 1) Direct retainers.
• 2) Indirect retainers.
• Direct retainers:
• 1) Intra-coronal: precision attachment (key & keyway preparation on the abutment).
• 2) Extra-coronal: (Clasps): (engages the abutment teeth in area cervical to the greatest convexity of the
tooth).

CLASPS: EXTRA-CORONAL DIRECT RETAINERS.
• Clasps to accommodate functional movement: allows limited movement in distal extension base.
• Gingival approach:
• RPI
• RPA
• Bar Clasp (Y, T, Modified T bars)

• Clasps without movement accommodation:
• Occlusal approach:
• Circumferential clasp (C-Clasp): Ring clasp or Embrasure clasp.

• Indirect retainers:
• The main purpose of indirect retainers is to resist movement against fulcrum line especially in bounded
long or free ended saddles.
• some forms of indirect retainers: 1) auxiliary occlusal rests.
• 2) canine rests.
• 3) canine extensions of occlusal rests.

C) RPD STABILITY:
• Achieved by :
• 1)Rests: vertical support for partial denture.
• 2)Major connectors: cross-arch stability.
• 3)Minor connectors: transferring effects of stabilizing components throughout the prosthesis.

3) LONGEVITY AND PROGNOSIS:
• The first reports about removable partial dentures (RPDs) indicated that these restorations could
deteriorate the health of remaining dentition and surrounding oral tissues(Carlsson et al., 1965 &
Roberts, 1978).
• Few partial dentures survived for more than 5 to 6 years(Wetherell and Smales, 1980)
• Other studies demonstrated more favorable results with respect to treatment with RPDs and suggested
that the negative effects could be counteracted by a carefully planned prosthetic treatment and regular
recall appointments that included patient instruction, retreatments of teeth, and prosthetic
adjustments.(Bergman et al., 1982), (Schwalm et al., 1977) and (Rissin et al., 1985).
• Regarding to longevity of RPDs we will discuss two papers in this lectures:
1. Ten-year evaluation of removable partial dentures: Survival rates based on retreatment, not wearing
and replacement (Vermeulen et al., 1996).
2. Treatment outcomes with RPDs: a retrospective study (Rehmann et al., 2013)

MATERIALS AND METHODS:
PARTICIPANTS:
• The total sample consisted of 1480 patients, 68% of whom were women. The mean age
was 38 years (range 19 to 72 years).
• To ensure a reasonable follow-up time, only those patients who started their treatment
at least 5 years before this analysis were selected, resulting in an exclusion of 389
patients.
• The remaining patients (n = 1036) were treated with a metal frame RPD that could be
of a conventional design or provided with attachments.
• The RPDs were subdivided into extension base and tooth-supported base categories.

CRITERIA OF
EVALUATION:
• At the start of the study the distribution of the remaining
dentition and the dental health was scored with the
following standard methods:
• Caries determination with a mirror, explorer or
radiograph.
• Pocket measurement with a pocket probe.
• Determination of tooth mobility with a 4 grade scale.
• Measurement of alveolar bone height radiographically.
• The dentitions were classified according to Kennedy
Classification.
• During the recall visits the changes that occurred to the
teeth, the restorations, and the RPDs were recorded.
Even, all retreatment of the RPDs and treatments of
abutment teeth were recorded.

• To study the survival rate, failure were distinguished:
• (1) treatment of the abutment teeth: (new restoration or extraction).
• Many abutments were filled with plastic filling material and only one third were crowned, which resulted
in a large portion of abutment teeth at risk for retreatment.
• (2) corrections of the RPD (Relining, Repairing, Rebasing or Reconstruction).
• As expected, extension base of RPDs especially in the mandible, needed a higher percentage of
adjustments of the denture base.
• (3) replacement of or not wearing the RPD.
• The reason “not wearing” accounted for 5% of the failures in RPDs with attachments, whereas in
conventional RPDs these percentages were 8% for the mandible and 4% for the maxilla.

RESULTS:
• By use of the first retreatment of one of the abutment teeth, as the criterion for failure, approximately
40% of the conventional RPDs survived 5 years and over 20% survived 10 years.
• The differences within the groups of conventional RPDs and within the groups of RPDs with attachments
were limited.
• The percentage of RPDs that presented no fracture within 5 years was 80% to 90%; after 10 years the
percentages of RPDs with no fracture varied between 56% and 73%.
• In 40% and 20% of the jaws with conventional RPDs no restorative retreatment of any of the abutment
teeth was performed after 5 and 10 years, respectively.

• For RPDs with attachments “abutment retreatment” resulted in 59% to 76% survival after 5 years and 30% to
48% after 10 years.
• A higher percentage of extension base RPDs needed an adjustment of the denture base within a shorter time
than did tooth-supported base RPDs. This phenomenon was found especially in extension-base RPDs with
attachments in the mandible.
• Another factor of failure was fracture of the RPD. The percentage of extension-base RPDs with attachments in
the maxilla after 10 years is not presented because of the low number at risk at that moment.
• The differences within the groups of conventional RPDs and within the groups of RPDs with attachments were
limited.

• Extension-base conventional RPDs tended to show lower survival percentages than did tooth-supported base
RPDs.
• For RPDs with attachments in the mandible the survival curves of the extension-base RPDs were less favorable
than those with tooth-supported bases.

• This longitudinal study was conducted on 748 patients with 886 RPDs examined during a 5- to l0-year
span.
• Another phenomenon observed was also the high retreatment marked increase in caries caused by
wearing RPDs. In the need of extension-base RPDs with attachments, leading to a decrease of these
restorations in later groups. Therefore, it is not appropriate to compare RPDs with and without
attachments.
• The results of this study did not find any increase in caries caused by wearing RPDs like (Bergman et al.,
1982).
• (Bergman et al., 1982) reported 44% of the abutment teeth in need of restorative treatment after 10
years.
• A recent study by Drake and BeckI demonstrated the importance of patient education, good oral self-
care, and regular professional recall for people who wear RPDs.
• It should be considered, however, that the first restorative treatment of one of the abutment teeth was
DISCUSSION

• Many abutments were filled with plastic filling material and only one
third were crowned, which resulted in a large portion of abutment
teeth at risk for retreatment.
• Many of the extension-base RPDs were provided with ball
attachments, which may be responsible for the unfavorable results
of the RPDs with attachments. During the first years of the study the
ball attachments were not provided with occlusal rests, resulting in
excessive pressure on the alveolar bone and as a consequence a
high resorption rate, responsible for the high number of
adjustments needed. This problem could be prevented if the ball
attachments were supplied with vertical occlusal stops.
• This can be explained by the progression of the resorption free-end
denture base which was probably intensified by the pressure of the
free-end denture base.

• The fracture percentages of RPDs can be considered low considering the high number of casting defects
and inaccuracies mentioned in several studies.
• The results of this study are confirmed by (Cowan et al., 1991) who reported a high number of patients
wearing their RPD several years after insertion without apparent problems.
• When replacement and not wearing of the RPD were combined as a criterion for failure, about 50% of
the RPDs survived 10 years, this finding is in contrast with the results of Wetherell and Smales. who
reported that only few prostheses lasted for more than 5 to 6 years. They reported a large number of
RPDs that were not worn.
• The results of this study are confirmed by Cowan et a1. who reported a high number of patients wearing
their RPD several years after insertion without apparent problems.

CONCLUSION
• Within the limits of this study it was concluded that the survival rate for
conventional metal frame RPDs, on the basis of replacement and not wearing, is
approximately 75% after 5 years and 50% after 10 years.
• The negative effect of an RPD on the remaining teeth can be kept to a minimum.
• With a simple RPD design and a regular surveillance of the patient in a recall
system with an individually adjusted interval, the results of RPD treatment will
ensure predictability.

Materials and methods:
• The total sample size was 52 patients (24 women, 28 men, age range:21 to 86 years).
• Before treatment, all patients underwent an oral hygiene program.
• Preliminary impression was taken by Alginate to pour study casts.
• All treatment planning were carried out by the authors.
• It was necessary to simplify the denture design to minimize the number of stagnant sites (the location on
the surface of a tissue where there is a tendency for food debris to accumulate) and avoid gingival
coverage by the retentive elements and connectors as much as possible (Berg, 1985 & Zarb, 1978)

• After tooth preparation, final impression was taken by Alginate (CA 37).
• The master casts were poured using vacuum mixed type 4 stone (Fujicork, GC) .
• After receiving their dentures, all patients were referred to participate in continuous follow-up program.
• 31 patients with 35 RPDs were not interested, thus not included in follow-up.
• The variables gender, denture location, number of clasped teeth, Kennedy class and impact of
participation in follow-up program were analyzed as covariates of the survival function in Cox regression
method.
• 31 patients with 35 RPDs were not interested, thus not included in follow-up.
• The variables gender, denture location, number of clasped teeth, Kennedy class and impact of
participation in follow-up program were analyzed as covariates of the survival function in Cox regression
method.

RESULTS:
• During the observation period, 9.2% of RPDs ceased to function and 5.8% of the abutment teeth were
extracted.
• The mean expected survival time of RPDs was 8.07 ± 0.66 years.
• The positive outcome probability after 5 years was 90%
• The Cox regression analysis revealed no significant impact of any other parameters on the clinical
outcomes .
• The mean observation time till first repair was 4.6 ± 0.64 years.
• 30 of 65 RPDs needed at least one repair.
• 9 RPDs needed two repairs.
• 4 needed three repairs.
• 1 needed four repairs.

The main reasons for repair were relining (n=23), clasp activation (n=9) and clasp fracture
(n=6).

• After five years, the RPDs in this study, which were fabricated according to hygienic principles, showed a
higher survival rate than clasp retained prosthesis with metal framework in other studies.
• This difference in survival rate is even greater than it appears because simple input output statistics
overestimates the survival function with relatively small sample size in Chandler and Brudvik, may explain
the very high outcome probability.

• Many authors (Bergman et al., 1982,CARLSSON et al., 1976 and Kapur et al., 1994) have emphasized the
strong influence of a continuous follow-up program on the clinical outcomes of RPDs.
• Previous studies (Zlatarić et al., 2002, Do Amaral et al., 2010) have reported that clasp has negative effect
on the periodontal condition of abutment teeth.
• It is unclear whether these effects or patient’s participation in oral hygiene programs decisively influence
the longevity of the RPD.
• In this study no influence of the follow-up program could be identified.
• It would have been useful to examine the periodontal status of the clasped teeth as well as the presence
of caries. This limitation is a shortcoming of this study.
• Patient gender, number of clasped teeth and Kennedy class showed no significant impact on the clinical
outcomes.
• The results suggested that the configuration of remaining dentition (except for location) may be less
important regarding the clinical outcome of RPD than assumed.

CONCLUSIONS:
• The high survival probability and low extraction rate (5.8%) of abutment teeth in this study indicate
that removable partial dentures designed according to hygienic principles met or even exceeded the
results reported by similar studies, therefore greater attention should be paid to RPD design principles
that minimize the risks of tissue injury and plaque accumulation in accordance with modern concepts
of preventive dentistry.
• Prosthesis location (Maxilla or Mandible) was the only parameter that significantly influenced the
survival probability.

FIXED PARTIAL DENTURE:
1) CLASSIFICATION
• Prosthodontic Diagnostic Index (PDI)
• Class I: characterized by ideal or minimal compromise in the location and extent of edentulous area (which is
confined to a single arch), abutment conditions, occlusal characteristics, and residual ridge conditions. All four
of the diagnostic criteria are favorable.
• 1. The location and extent of the edentulous area are ideal or minimally compromised: The edentulous area is
confined to a single arch. The edentulous area does not compromise the
• physiologic support of the abutments. The edentulous area may include any anterior maxillary span that does
not exceed two incisors, any anterior mandibular span that does not exceed four missing incisors, or any
posterior span that does not exceed two premolars or one premolar and one molar.
• 2. The abutment condition is ideal or minimally compromised, with no need for pre-prosthetic therapy.
• 3. The occlusion is ideal or minimally compromised, with no need for preprosthetic therapy; maxillomandibular
relationship consists of Class I molar and jaw relationships.
• 4. Residual ridge morphology conforms to the Class I complete edentulism description.

• Class II:
• This class characterized by moderately compromised location and extent of edentulous areas in both arches,
abutment conditions necessitating localized adjunctive therapy, occlusal characteristics necessitating
adjunctive therapy, and residual ridge conditions.
• 1. The location and extent of the edentulous area are moderately compromised: Edentulous areas may exist
one or both arches. The edentulous areas do not compromise the physiologic support of the abutments.
Edentulous areas may include any anterior maxillary span that does not exceed two incisors, any anterior
mandibular span that does not exceed four incisors, any posterior span (maxillary or mandibular) that does
exceed two premolars, or one premolar and one molar or any missing canine (maxillary or mandibular).
• 2. Condition of the abutments is moderately compromised: Abutments in one or two sextants have
tooth structure to retain or support intracoronal or extracoronal restorations. Abutments in one or two
sextants require localized adjunctive therapy
• 3. Occlusion is moderately compromised: Occlusal correction requires localized adjunctive therapy.
Maxillomandibular relationship: Class I molar and jaw relationships.
• 4. Residual ridge structure conforms to the Class II complete edentulism description.

• Class III
• characterized by substantially compromised location and extent of edentulous areas in both arches,
abutment condition necessitating substantial localized adjunctive therapy, occlusal characteristics
necessitating reestablishment of the entire occlusion without a change in the occlusal vertical
and residual ridge conditions.
• 1. The location and extent of the edentulous areas are substantially compromised: Edentulous areas
be present in one or both Arches. Edentulous areas compromise the physiologic support of the
abutments. Edentulous areas may include any posterior maxillary or mandibular edentulous area
than three teeth or two molars or anterior and posterior edentulous areas of three or more teeth.
• 2. The condition of the abutments is moderately compromised: Abutments in three sextants have
insufficient tooth structure to retain or support intracoronal or extracoronal restorations. Abutments in
three sextants require more substantial localized adjunctive therapy (i.e., periodontal, endodontic or
orthodontic procedures). Abutments have a fair prognosis.
• 3. Occlusion is substantially compromised: Requires reestablishment of the entire occlusal scheme
without an accompanying change in the occlusal vertical dimension. Maxillomandibular relationship:
Class II molar and jaw relationships.
• 4. Residual ridge structure conforms to the Class III complete edentulism description.

• Class IV
• characterized by severely compromised location and extent of edentulous areas with guarded prognosis,
abutments requiring extensive therapy, occlusion characteristics necessitating reestablishment of the
with a change in the occlusal vertical dimension, and residual ridge conditions.
• 1. The location and extent of the edentulous areas result in severe occlusal compromise: Edentulous areas
be extensive and may occur in both arches. Edentulous areas compromise the physiologic support of the
abutment teeth, and so the prognosis is guarded. Edentulous areas include acquired or congenital
maxillofacial defects. At least one edentulous area has a guarded prognosis.
• 2. Abutments are severely compromised: Abutments in four or more sextants have insufficient tooth
to retain or support intracoronal or extracoronal restorations. Abutments in four or more sextants require
extensive localized adjunctive therapy. Abutments have a guarded prognosis.
• 3. Occlusion is severely compromised: Reestablishment of the entire occlusal scheme, including changes in
occlusal vertical dimension, is necessary. Maxillomandibular relationship: Class II, division 2, or Class III molar
and jaw relationships.
• 4. Residual ridge structure conforms to the Class IV complete edentulism description.
• Other characteristics include severe manifestations of local or systemic disease, including sequelae from
oncologic treatment, maxillomandibular dyskinesia and/or ataxia, and refractoriness (a patient’s presenting
with chronic complaints after appropriate therapy).

2) TREATMENT PLAN
• Objectives of treatment:
1. Correction of existing disease.
2. Prevention of future disease.
3. Restoration of function.
4. Improvement of appearance.

SEQUENCE OF TREATMENT:
1. Treatment of symptoms: (Mostly Pain)
2. Stabilizing the deteriorating conditions: (Caries and periodontal condition)
3. Definitive therapy : a) Oral surgery.
b) Periodontics.
c) Endodontics.
d) Orthodontics.
e) Prosthodontics.

3) LONGEVITY AND PROGNOSIS:
• In this lecture we will discuss two papers regarding the longevity of FPDs.
• 1) A systematic review of the survival and complication rates of all-ceramic and metal–ceramic
reconstructions after an observation period of at least 3 years. (Sailer et al., 2007)
• 2) All-ceramic or metal-ceramic tooth-supported fixed dental prostheses (FDPs)? A systematic review of
the survival and complication rates. (Pjetursson et al., 2015)

• The objective of this systematic review was to assess the 5-year survival rates and incidences of
complications of all-ceramic fixed dental prostheses (FDPs) and to compare them with those of metal–
ceramic FDPs.
• The data on survival and complication rates of metal–ceramic FDPs were obtained from a previous
systematic review of (Tan et al. 2004) and the updated version from the same authors (Pjetursson et al.
2007).
• Methods:
• Patients had to have been examined clinically at the follow-up visit.
• Assessment of the identified studies and data abstraction was performed independently by three
reviewers.
• Failure rates were analyzed using standard and random-effects Poisson regression models to obtain

The results:
• Full-text analysis was performed for 39 articles, resulting in 9 studies of ceramic FDPs and 5 of metal-
ceramic FDPs that met the inclusion criteria.
• The data on survival and complication rates of metal–ceramic FDPs were obtained from a previous
systematic review of Tan et al. (2004) and the updated version from the same authors (Pjetursson et al.
2007).
• The 5-year survival of metal–ceramic FDPs was significantly higher with 94.4% than the survival of all
ceramic FDPs, being 88.6%.
• The frequencies of material fractures (framework and veneering material) were significantly higher for all-
ceramic FDPs compared with those of metal–ceramic FDPs.
• Other technical complications like loss of retention and biological complications like caries and loss of
pulp vitality were similar for the two types of reconstructions over the 5-year observation period.

STUDY CHARACTERISTICS:
• A total of nine studies of all-ceramic FDPs, all but one prospective, were included in this review.

• The metal–ceramic FDPs were all porcelain-fused-to-metal (PFM) reconstructions with total of five
studies.

FDP SURVIVAL:
• All ceramic FDPs:
• Thirty-three FDPs were reported to be lost. In meta-analysis, the annual failure rate was estimated to be
at 2.42 translating into a 5-year survival rate for all-ceramic FDPs.

FDP SURVIVAL:
• Metal ceramic FDPs:
• The annual failure rate was estimated at 1.15 translating into a 5- year survival rate for metal–ceramic
FDPs.

FDP SURVIVAL:
• Compared with metal–ceramic FDPs, the annual failure rate of all-ceramic FDPs was 2.11 times higher.

COMPLICATIONS OF FDP:
• The analysis of the biological complications encompassed caries, loss of pulp vitality, abutment tooth
fracture and periodontal disease progression.
• Technical complications included fracture of the framework, fracture or chipping of the veneering
ceramic, marginal gap/ discoloration and loss of retention.

BIOLOGICAL COMPLICATIONS:
• CARIES:
• All ceramic FDPs: The estimated annual rate of secondary caries was 0.36, translating into a 5-year
complication rate of 1.8% (95% CI: 0.2–16.9%) for all ceramic FDPs.
• Information about loss of the entire reconstruction due to secondary caries was given in all nine studies.
In only one study (Sailer et al. 2007) were all-ceramic FDPs reported to be lost. Six of the original 57
FDPs were lost in this investigation.
• The annual FDP failure rate due to secondary caries was 0.34%. The estimated rate of ceramic FDPs lost
due to caries over a 5 year observation period was 1.7%.
• Conventional FDPs: exhibited a rate of secondary caries after 5 years of 4.8% (95% CI: 2.3–9.9%)
(Pjetursson et al. 2007).
• Compared with all-ceramic FDPs there was no significant difference in the rate of conventional FDPs lost
due to caries.
• The estimated 5-year rate for loss of conventional FDPs due to caries was 1.6% (95% CI: 1.1–2.3%)
(Pjetursson et al. 2007)

• Loss of vitality:
• All ceramic FDP:
• Loss of abutment vitality was reported in two studies of all-ceramic FDPs.
• The annual complication rate ranged between 0.74 and 1.37.
• the estimated rate of vital abutments that had lost pulp vitality over a 5-year observation period was
4.1%.
• Conventional FDP:
• The estimated rate of vitality loss of abutments supporting conventional FDPs was 6.1% (Pjetursson et al.
2007).
• No significant difference was found when the rate of loss of abutment vitality for ceramic FDPs was
compared with those of conventional FDPs (Pjetursson et al. 2007).

• Abutment tooth fracture:
• FDPs lost due to fracture of abutment teeth were reported in two of the nine studies on all-ceramic FDPs.
The failure rate ranged between 0 and 1.89.
• The estimated rate of FDP loss due to abutment tooth fracture over a 5-year period was 1.2%.
• Conventional FDPs:
• The estimated rate of conventional metal–ceramic FDPs lost due to abutment tooth fracture after 5 years
was 1% (Pjetursson et al. 2007).

• Periodontal disease:
• All nine studies on all-ceramic FDPs provided information on reconstructions lost due to recurrent
periodontal disease during the observation period. In none of the studies were FDPs lost due to
periodontitis. Hence, the failure rate was 0%.
• The estimated rate of conventional metal ceramic FDPs that were reported to be lost due to recurrent
periodontitis was comparably low with 0.4% after 5 years (Pjetursson et al. 2007).

TECHNICAL COMPLICATIONS:
Material complications: framework fracture, veneer chipping or fracture:
• The estimated 5-year rate of all-ceramic FDPs lost due to fracture of the framework was 6.5%.
• The annual failure rate due to framework fracture ranged between 1.88 and 4.24 for these materials.
• Fracture of a zirconia framework, however, was a rare complication, only observed in one of the studies
analyzing this new ceramic material. The annual failure rate of zirconia framework fracture ranged
between 0 and 0.48.
• The most frequent technical problem of FDPs with zirconia frameworks was minor chipping or extended
fracture of the veneering ceramic. Not only observed with zirconia, however, the estimated complication
rates were lower.
• The estimated rate of all-ceramic FDPs lost due to fracture of veneering ceramic after 5 years was 6.5%.
• Chipping of the veneering ceramic was not reported in any of the studies evaluating InCeram FDPs.
• The estimated rate of veneer or framework fracture reported for conventional FDPs with metal

• For glass-ceramic and InCeram FDPs fracture of the ceramic framework occurring in the connector area
was the most frequent reason for failure (Scurria et al. 1998).
• The highest stress within FDPs was located at the gingival side of the connector area (Filser et al. 2001a,
2001b; Fischer et al. 2003).
• As ceramics are brittle, their resistance to tension is low, promoting cracks and subsequent fracture
(Filser et al. 2001a, 2001b; Pospiech et al. 2003).
• Therefore, ceramics like zirconia with higher bending strength and fracture toughness have been
developed not only for high esthetic results, but also for periodontal health, since the cross-section of
the connector in conventional ceramics needs to be enlarged in order to increase he stability of the
framework which eventually affect periodontal health around the prosthesis.
• Survival was defined as the FDP remaining in situ at the examination visit with or without modifications.

Loss of retention:
• Five of the nine studies on all-ceramic FDPs addressed the issue of loss of retention.
• estimated rate of loss of retention of ceramic FDPs after 5 years 2.3%.
• The estimated rate of loss of retention for conventional metal–ceramic FDPs after 5 years was
comparable with 3.3% (Pjetursson et al. 2007).

Marginal discoloration:
• The estimated annual complication rate ranged between 0 and 10. The highest rate of marginal
discoloration was found in a study on zirconia FDPs.
• The highest rate of marginal discoloration was found in a study on zirconia FDPs.
• The estimated 5-year rate of ceramic FDPs exhibiting marginal gaps or discoloration was as high as
15.3%.

• Caries:
• Caries was found to be the second most frequent biological complication in both types of FDPs.
• In this study, marginal gaps were frequently found, leading to secondary caries in more than 20% of the
reconstructions.
• All ceramic: no caries was reported for glass-ceramic and InCeram FDPs, resulting in an average complication
rate for caries of abutment teeth of 1.8% and for loss of FDP due to caries of 1.7% after 5 years of observation.
• Conventional: Caries was found in 4.8% of the abutment teeth of conventional metal–ceramic FDPs after 5
years.
• Technical complications:
• All ceramic: The worst technical complication for allceramic FDPs, of course, was catastrophic fracture of the
framework, yielding a loss of 6.5% of the all-ceramic FDPs during a 5- year observation period.
• The most frequent technical complication reported for all-ceramic FDPs was marginal discoloration (15.3%),
which was observed for InCeram and zirconia FDPs (Sua´rez et al. 2004; Raigrodsky et al. 2006; Sailer et al.
2007).
• The rate for ceramic chipping was 13.6% after 5 years of observation.
• Conventional: Compared with all-ceramic FDPs, material fracture (framework or veneering) was rarely seen by

DISCUSSION:
• All-ceramic reconstructive materials were developed to overcome the esthetic problems could be shown
in metal ceramic restorations in several situations (McLean & Hughes 1965; Sadoun 1988).
• The main and may be the sole advantage of all-ceramic materials lies in their excellent conditions to
obtain optimal esthetic treatment outcomes.
• However, due to their low mechanical stability, all-ceramic systems (feldspathic-, glass- and glass-
reinforced ceramics) only seem suitable for single crowns (Sorensen et al. 1998a; Pospiech et al. 2000;
Olsson et al. 2003; Zimmer et al. 2004).
• More recently, Zirconia is the most stable of these high-strength ceramics and has flexural strength and
fracture toughness values two times higher than those achieved by glass-ceramics and glass-infiltrated
alumina (Olsson et al. 2003; Zimmer et al. 2004).

• It may be argued that follow-up periods of only 3 years are too short to obtain reliable information on
+survival and complication rates.
• However, information on the long-term survival of ceramic FDPs is still sca, while conventional metal–
ceramic FDPs have been followed for decades.
• The failure rate of all-ceramic FDPs after 5 years was 11.4%. The corresponding figure for metal–ceramic
FDPs was 5.6%, resulting in a 2.11-fold higher failure of all-ceramic FDPs.
• The risk for biological and technical complications might increase with time.
• InCeram: most frequent reason for failure was fracture of the reconstruction (framework and veneering
ceramic).
• The most frequent complication reported for both all-ceramic and conventional FDPs was loss of pulp
vitality, 4.1% of vital abutment teeth with all-ceramic and at 6.1% of teeth with metal ceramic FDPs
respectively (Pjetursson et al. 2007).

• Conclusion:
• Based on the present systematic review of all-ceramic FDPs, significantly lower survival rates at 5 years
were seen compared with metal–ceramic FDPs.
• The most frequent reason for failure of FDPs made out of glass-ceramics or glass-infiltrated ceramics
fracture of the reconstruction (framework and veneering ceramic).
• However, when zirconia was used as framework material, the reasons for failure were primarily
and technical complications other than framework fracture.
• In conclusion, if posterior teeth shall be replaced with an all-ceramic FDP, zirconia should be used as
framework material.
• However, the veneering ceramics for this high-strength framework material exhibit higher rates of
chipping than the ones observed for metal frameworks.
• Shortcomings of the marginal accuracy of zirconia reconstructions will be overcome by further
refinements of the computerized production technologies in future.

• The objectives of the present systematic review was therefore:
• (i) to update the previous systematic review (Sailer et al., 2007) on tooth-supported FDPs with an
additional literature search including retrospective and prospective studies from 2007to 2013.
• (ii) to assess the 3-year survival rate of tooth-supported fixed dental prostheses (FDPs) and to describe
the rate of biological, technical and esthetic complications.
• (iii) to compare the survival and complication rates of metal-based FDPs and all-ceramic FDPs.

METHODS:
• Medline (PubMed), Embase and Cochrane Central Register of Controlled Trials
(CEN-TRAL) searches (2006–2013) were performed for clinical studies focusing on
tooth-supported FDPs with a mean follow-up of at least 3 years.
• This was complemented by an additional hand search and the inclusion of 10
studies from a previous systematic review.
• Survival and complication rates were analyzed using robust Poisson’s regression
models to obtain summary estimates of 5-year proportions.

RESULTS:
• Forty studies reporting on 1796 metal-ceramic and 1110 all-ceramic FDPs fulfilled the inclusion criteria.
• Meta-analysis of the included studies indicated an estimated 5-year sur-vival rate of metal-ceramic FDPs of
94.4% (95% CI: 91.2–96.5%).
• The estimated survival rate of reinforced glass ceramic FDPs was 89.1% (95% CI: 80.4–94.0%), the survival rate
of glass-infiltrated alumina FDPs was 86.2% (95% CI: 69.3–94.2%) and the survival rate of denselysintered
zirconia FDPs was 90.4% (95% CI: 84.8–94.0%) in 5 years of function.
• Even though the survival rate of all-ceramic FDPs was lower than for metal-ceramic FDPs, the differences did
not reach statistical significance except for the glass-infiltrated alumina FDPs (p = 0.05). A significantly higher
incidence of caries in abutment teeth was observed for densely sintered zirconia FDPs compared to metal-
ceramic FDPs.
• Significantly more framework fractures were reported for reinforced glass ceramic FDPs (8.0%) and glass-
infiltrated alumina FDPs This

• Focused questions:
• “What are the survival and complication rates of tooth-supported FDPs after a mean observation
of at least 3 years?”
• “Are the survival and complications rates of metal-ceramic and all-ceramic tooth-supported FDPs
after a mean observation period of at least 3 years?”
• PICO
• The PICO for the present systematic review was defined as follows:
• P Population: subjects with anterior and/or posterior fixedtooth-supported FDPs.
• I Intervention: all-ceramic FDP.
• C Comparison: metal-ceramic FDP.
• O Outcome: clinical survival and technical, biological andesthetic complication rates.

• 28 studies, published between 1998 and 2013, on all-ceramic FDPs and 15 studies, published between
1989and 2013, on metal ceramic FDPs, were included in this review.
• FDP survival:
• For metal-ceramic FDPs, 15 studies provided data on 1796 FDPs after a mean follow-up time of 7.0
years. Out of these, 145FDPs were reported to be lost. The annual failure rate was estimated at 1.15%
(95% CI: 0.72–1.84%), translating into a 5-year survival rate for metal-ceramic FDPs of 94.4%.
• The results for all-ceramic FDPs was divided split into reconstructions based on:
• 1) reinforced glass ceramic, glass-infiltrated alumina (InCeram Alumina and InCeram Zirconia).
• For reinforced glass ceramic FDPs, The annual failure rate was estimated at 2.31% translating into a 5-
year survival rate for reinforced glass ceramic FDPs of 89.1% .
• For glass-infiltrated alumina FDPs, The annual failure rate was estimated at2.97% translating into a 5-
year survival rate for glass-infiltrated alumina FDPs of 86.2%
• 2) densely sintered zirconia: The annual failure rate was estimated at 2.02% translating into a 5-year
survival rate for densely sintered zirconia FDPs of 90.4%.

DISCUSSION:
• At the 5-year follow-up, the annual failure rates of different types of FDPs ranged from 1.15% to 2.97%
and the 5-year survival ranged from 86.2% to 94.4%.
• All-ceramic FDPs showed higher annual failure rates.

BIOLOGICAL COMPLICATIONS:
Secondary caries:
• The overall annual complication rate was 0.29%, translating into a 5-year complication rate of 1.4%. For
different types of FDPs the annual rate of secondary caries ranged from 0.11% to 0.65%.
• The lowest annual complication rate 0.11% was reported for reinforced glass ceramic FDPs and the
highest complication rate 0.65% was reported for densely sintered.
• Using metal-ceramic FDPs as reference, densely sintered zirconia FDPs experienced significantlyhigher
rate of secondary caries.
• The difference between different types of FDPs did not reach statistical significance.

Loss of vitality:
• Loss of abutment vitality was reported in three studies. All of them reporting on densely sintered zirconia
FDPs.
• The annual complication rate was 0.44%, translatinginto a 5-year complication rate of 2.2%.
Abutment tooth fracture:
• The overall annual failure rate was 0.17%, trans-lating into a 5-year failure rate of 0.9%.
• For differenttypes of FDPs the annual failure rates due to abutment toothfractures ranged from 0.09% to
0.21%.
• The difference betweendifferent types of FDPs did not reach statistical significance.
Periodontal disease:
• The overall annual failure rate was0.23%, translating into a 5-year failure rate of 1.2%.
• For different types of FDPs, the annual failure rates due to recurrent periodontal diseases ranged from
0.06% to 1.59%.
• The highest annual failure rate was reported for reinforced glass ceramic FDPs 0.60% and glass-infiltrated
alumina FDPs1.59%, translating into a 5 years failure rates of 2.9% and 7.6%,respectively.
• Using metal-ceramic FDPs as reference, significantly more glass-infiltrated alumina FDPs and reinforced

TECHNICAL COMPLICATIONS:
Material complications: framework fracture, ceramic chipping or ceramic fracture:
• The overall annual failure rate was 0.45%, translating into a 5-year failure rate of 2.2%.
• 1) Framework fracture:
• For different types of FDPs, the annual failure rates of framework fractures ranged from 0.12% to 2.76%.
• The highest annual failure rate was reported for reinforced glass ceramic FDPs (1.68%) and glass-
infiltrated alumina FDPs (2.76%), translating into a 5-year failure rates of 8.0% and 12.9%, respectively.
• Using metal-ceramic FDPs as reference, significantly more glass-infiltrated alumina FDPs and reinforced
glass ceramic FDPs were lost due to framework fractures.
• Compared to the other ceramics, densely sintered zirconia exhibited the highest stability as framework
material with an estimated 5-year failure rate of 1.9%.

• 2) Ceramic fracture:
• fractures of the ceramic veneering that needed repair or replacement was highest for densely sintered
zirconia FDPs with an annual complication rate of 3.14%,translating into a 5-year complication rate of
14.5%. This difference reached statistical significance.
• 3) Ceramic chipping:
• The overall annual complication rate was 2.71%, translating into a 5-year complication rate of 12.7%.
• For different types of FDPs, the annual complication rates ranged from 1.07% to 7.55%.
• Ceramic chipping was the most frequent technical complication reported, but the difference in ceramic
chipping between different types of FDPs did not reach statistical significance.

Loss of retention:
• The overall annual com-plication rate was 0.64%, translating into a 5-year failure rate of 3.1%.
• Densely sintered zirconia FDPs experienced statistically significantly more retention loss than the other
types of FDPs with an annual complication rate of 1.28% and a 5-year complication rate of 6.2%.
• For other types of FDPs the annual complication rates ranged from 0.42% to 0.58%, translating into a 5-
year failure rates of 2.1–2.9%.
Marginal discoloration:
• The overall annual complication rate was 3.91%, translating into a 5-yearcomplication rate of 17.7%.
• The lowest incidence of marginal discoloration was seen for reinforced glass ceramic with annual
complication rate of 0.72% or a 5-year complication rate of 3.5%.
• For the other three types of FDPs, the annual rates of marginal discoloration ranged between 3.77%and
6.72%
• The highest incidence reported for densely sintered zirconia FDPs, representing a 5-year complication
rate of 28.5%

CONCLUSION:
• Metal-ceramic FDPs had lower failure rates than all-ceramic FDPs after a mean observation period of
at least 3 years.
• Framework fractures were frequently reported for reinforced glass ceramic and glass-infiltrated alumina
FDPs.
• Densely sintered zirconia:
1. more stable significantly as framework material, but misfit lead to complications such as discol-
orations, secondary caries and loss of retention.
2. ceramic fractures and chipping of ceramics were frequent.
• GENERALLY: In the future, further refinements in the production of all-ceramic reconstructions are
indicated.

MAIN REFRENCES:
• Sailer I, Pjetursson BE, Zwahlen M, Ha¨mmerle CHF. A systematic
review of the survival and complication rates of all-ceramic and
metal–ceramic reconstructions after an observation period of at least
3 years. Part II: fixed dental prostheses.
• Bjarni Elvar Pjeturssona, Irena Sailer b, Nikolay Alexandrovich
Makarovb, Marcel Zwahlenc, Daniel Stefan Thomad. All-ceramic or
metal-ceramic tooth-supported fixed dental prostheses (FDPs)? A
systematic review of the survival and complication rates. Part II:
Multiple-unit FDPs.
• A. H. B. M. Vermeulen, DDS, PhD,” H. M. A. M. Keltjens, DDS, PhD,M.
A. van Hof, PhD,b and A. F. Kayser, DDS, PhD, Ten-year evaluation of
removable partial dentures: Survival rates based on retreatment, not
wearing and replacement.
• Rehmann P, Orbach K, Ferger P, Wöstmann B. Treatment outcomes
with removable partial dentures: a retrospective analysis.
• Contemporary fixed prosthodontics (5th edition)
• McCracken's Removable Partial Prosthodontics (13th edition)

Longevity of treatment options for partially edentulous patients

Recommandé

Recommandé

Contenu connexe

Tendances

Tendances (20)

Similaire à Longevity of treatment options for partially edentulous patients

Similaire à Longevity of treatment options for partially edentulous patients (20)

Dernier

Dernier (20)

Longevity of treatment options for partially edentulous patients