22 December 2021

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Resin-Bonded Fixed Dental Prostheses with Zirconia Ceramic Single Retainers: are they predictable after 10 years?

Allegra Comba

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In spite of rapid development in the field of dental adhesive protocols and materials, replacing single missing teeth in the esthetic regions of the maxilla and mandible is still an issue in terms of patient satisfaction. Such interventions have to satisfy functional, phonetic, and esthetic needs.
Today treatment options include an implant-supported single crown (SC), a conventional fixed dental prosthesis (FDP), or a resin bonded fixed dental prosthesis (RBFDP). The last option is chosen for patients with contraindications to implant therapy and for those requesting minimally invasive treatment. Some of the benefits associated with RBFDP are relatively low treatment costs and short treatment time. In the past decade, the concept of RBFDPs as a tooth replacement option has changed from a provisional to a permanent restoration due to continuous improvements in design, materials, and bonding techniques. 

However, at present, only limited long-term data are available in literature for this type of restoration. Thus, the  research group of Nadja Naenni et al. conducted a retrospective clinical study to assess the clinical outcomes of single-retainer RBFDPs after a mean observation time of 10 years.

Materials and methods
To conduct the retrospective research, the group of Dr Neanni et al. selected ten patients (mean age 32.4 years) who had received an RBFDP replacing a single anterior tooth for a follow-up visit. For each patient included in the study, the authors evaluated the following parameters: probing depth, bleeding on probing, modified plaque control record, gingival recession, measurement of the width of keratinized mucosa, and intraoral

photographs and radiographs. The modified criteria of the United States Public Health Services (USPHS) evaluation system were applied. Additionally, patient satisfaction was recorded. Data were analyzed descriptively, and the 10-year RBFDP survival rates were calculated using Kaplan-Meier analysis. 

Results
The results obtained by the group of Dr Neanni et al showed that the single-retainer RBFDPs replaced three maxillary central incisors, six maxillary lateral incisors, and one mandibular lateral incisor. Five of the recalled patients had received SCTG at the pontic area.
The RBFDP survival rate after a mean follow-up of 10.0 years (range 7.4 to 13.3 years) was 100%. Neither technical failures nor biologic complications were observed. All abutment teeth remained vital, and no secondary caries were detected. Between baseline and follow-up examinations, the profilometric changes at the pontic sites were minimal. 

Conclusions
The authors conclude that the restoration of anterior single-tooth gaps by means of an RBFDP is a viable treatment option. Indeed, results showed a high survival rate and low number of complications. In addition, stable soft tissue dimensions, over a period of 10 years was recorded. As concern patients perception of the treatment, they reported high level of satisfaction. Further investigations are needed to validate the result of the present retrospective clinical study. 

(Photocredit: Dr. Alberto Libero)

For additional information: Resin-Bonded Fixed Dental Prostheses with Zirconia Ceramic Single Retainers Show High Survival Rates and Minimal Tissue Changes After a Mean of 10 Years of Service