Root‐retained overdentures: Survival of abutment teeth with precision attachments on root caps depends on overdenture design

Abstract

Summary Background Root‐retained overdentures (OD) are one treatment option for partially edentulous patients. However, the available evidence regarding factors influencing abutment survival in root‐retained ODs is limited. Purpose This retrospective study included clinical examinations and evaluated the survival rate of roots restored with precision attachments soldered to post‐and‐core (gold cap) retained ODs, analysed with respect to various patient‐ and prosthesis‐related factors. Methods Patients receiving at least one OD with gold caps in the past were invited for comprehensive clinical examinations. The primary outcome parameter was the abutment survival rate over the observation period (2002‐2016). Possible contributing factors (eg closed vs open OD design) were analysed. Analyses included Kaplan‐Meier estimators, Cox regressions and hazard ratios (HR). Results 114 patients with 128 ODs originally retained by 280 abutments, with a cumulative total exposure time of 2035.4 years, were examined. Twenty‐seven abutment teeth (9.6%) were lost after a mean observation period of 7.9 ± 3.4 years. Significant factors associated with abutment loss were a closed, compared to an open OD design (HR 8.38 (95% CI 1.11‐63.59), P = .040), which was independent of the number of abutments per OD. Furthermore, the loss rate was higher when the denture was not worn day‐and‐night (HR 3.52 (95% CI 1.32‐9.40), P = .012). Oral hygiene behaviour was associated with higher HRs. Conclusions ODs remain a viable treatment option for patients with few teeth remaining in the dental arch. It is advisable to choose an open design for the OD, irrespective of the number of abutment teeth. Furthermore, gold cap‐retained ODs should not be removed overnight.

Clinical performance of tooth implant–supported removable partial dentures: a systematic review and meta-analysis

“…IARPDs could be a viable treatment alternative for partially edentulous patients compared with conventional RPDs. Furthermore, considering the option of extracting remaining teeth for implant overdentures, IARPDs represent an alternative that preserves remaining dentition, enabling the maintenance of alveolar bone and dental proprioception [ 35 , 36 ].…”

Tooth-Supported Overdentures Revisited

“…The cast coping can be extended into the root canal with or without a post, depending on the amount of tooth structure available. Post-retained coping may be extended into the root canal for at least 2/3 of its root length to enhance retention of the coping (Figure 3 ) [ 6 ]. These copings are used to protect a weakened tooth from fracture and excessive wear.…”

“…With this telescopic double crown abutment system, the overdenture can be designed as an open flange, allowing enhanced cleanability and improving salivary flow, leading to reduced plaque retention. This feature considerably reduced its biological complications on the abutment tooth [ 6 ]. This type of overdenture avoids unsightly clasp-retained removable dentures, particularly for an aesthetically concerned patient [ 6 ].…”

“…This feature considerably reduced its biological complications on the abutment tooth [ 6 ]. This type of overdenture avoids unsightly clasp-retained removable dentures, particularly for an aesthetically concerned patient [ 6 ]. On the other hand, the space requirements were rather meticulous to accommodate two crowns in a single abutment, rendering more tooth preparation and potentially requiring endodontic treatment prior [ 32 ].…”

“…The precision attachment of retained overdentures has shown many advantages over conventional removable overdentures. It has significantly improved the retention, support, and stability of the denture, facilitating the management of divergent abutments and potentially improving the aesthetic by avoiding visible retainers in the aesthetic zone [ 6 , 34 , 37 ]. The survival rate of such abutment was high and is reported to be 95% after five years and 88% after 10 years [ 6 ].…”