The influence of resilient liner and clip attachments for bar‐implant‐retained mandibular overdentures on opposing maxillary ridge. A 5‐year randomised clinical trial

Abstract

This study aimed to compare the influence of resilient liner and clip attachments for bar-implant-retained mandibular overdentures on opposing maxillary ridge after 5 years of denture wearing. Thirty edentulous male patients (mean age 62·5 years) received two implants in the anterior mandible after being allocated into two equal groups using balanced randomisation. After 3 months, implants were connected with resilient bars. New maxillary complete dentures were then constructed, and mandibular overdentures were retained to the bars with either clips (group I, GI) or silicone resilient liners (group II, GII). The prosthetic and soft tissue complications of the maxillary dentures were recorded 6 months (T6 m ), 1 year (T1), 3 years (T3) and 5 years (T5) after overdenture insertion. Traced rotational tomograms were used for measurements of maxillary alveolar bone loss. The proportional value between bone areas and areas of reference not subject to resorption was expressed as a ratio (R). Change in R immediately before (T0) and after 5 years (T5) of overdenture insertion was calculated. Maxillary denture relining times and frequency of flabby anterior maxillary ridge occurred significantly more often in GI compared with GII. The change of R in anterior part of maxilla was significantly higher than change of R in posterior part in both groups. GI showed significant resorption of anterior residual ridge compared with GII. Relining times and frequencies of flabby ridge were significantly correlated with change in R. Within the limitations of this study, resilient liner attachments for bar-implant-retained mandibular overdentures are associated with decreased resorption and flabbiness of maxillary anterior residual ridge and fewer maxillary denture relining times when compared with clip attachments.

Effect of Implant Position on Clinical and Radiographic Outcomes of Locator‐Retained Mandibular Overdentures: A 1‐Year Prospective Study

“…This prosthesis is simple to fabricate, cost effective, and exerts the least surgical damage to the tissues . Different attachment types can be used for such overdentures, including bars of different designs, balls, and magnetic and resilient telescopic attachments …”

Premaxilla Stress Distribution and Bone Resorption Induced by Implant Overdenture and Conventional Denture

“…Residual ridge resorption (RRR) in complete denture (CD) wearers is a continuous, inevitable process and is affected by the type of prostheses that overlay and also oppose the residual ridge . Several studies have shown greater RRR in the anterior maxilla beneath a maxillary CD opposed by a mandibular two‐implant‐retained overdenture (IOD) than in one opposed by a mandibular CD . In contrast, other studies have found no difference in the RRR rate between the two modalities of treatment or an even greater RRR in the case of conventional CD therapy attributable to lack of retention and stability …”

Locator Versus Bar Attachment Effect on the Retention and Stability of Implant‐Retained Maxillary Overdenture: An In Vitro Study

“…Moreover, these overdentures are indicated for patients with poor bone quality, buccal bone inclination, high lip line, thin mobile mucosa, and insufficient lip support to achieve proper phonetics and esthetics . Maxillary implant overdentures opposing mandibular implant‐retained prostheses may prevent development of degenerative changes of the maxillary ridge (combination syndrome) . Attachment systems used for relating implant‐retained overdentures to underlying implants include splinting (bar‐clip construction with various bar shape designs) and nonsplinting attachments (various ball types, magnets, resilient studs [Locators], and telescopic crowns) …”