Evaluation of Clinical Periodontal Parameters of Abutment Teeth Supporting Distal-Extension Base Removable Partial Dentures: A Cross-sectional Study

To assess the clinical periodontal status of abutment teeth in regards of different design components of distal-extension removable partial dentures. Subjects (N=100) with acrylic or cobalt-chromium distal-extension removable partial dentures were enrolled and their periodontal parameters plaque and gingival indices [PI, GI], probing depths [PD], clinical attachment loss [CAL] and a mobility index [MI] evaluated. Denture base type, major connector, occlusal rests position, design of direct retainers, retention, stability and denture wearing habits were further evaluated. Acrylic RPDs were associated with higher mean±SE PI [1.70±0.74], GI [1.76±0.55], PD scores [2.47±1.02 mm] and CAL values [4.46±2.11 mm] compared to CO-CR RPDs [p⟨0.05]. For abutments, the PI [1.6±0.83], GI [1.72±0.57], PD [2.32±1.03] and CAL [4.26±2.08] were higher than their non-abutments counterparts [p⟨0.05]. CAL scores were found to be significantly higher for mandibular abutments compared to maxillary ones [P=0.002]. The highest PI [1.83±1.10] and GI [2.00±0.00] scores were associated with lingual bars and horse-shoe connectors, respectively. Full palatal coverage and lingual plates were associated with the highest PD [2.80±0.48] and CAL [4.70±0.37] scores. Acrylic RPDs, type of major connector, wrought wire clasps and distal occlusal rests may be considered as risk factors for periodontal disease progression in distal-extension removable partial denture wearers.

Magnet-retained implant-supported overdentures: review and 1-year clinical report

Open-field aluminum-nickle-cobalt magnets have been used in prosthodontics for many years, but success has been limited because these magnets are susceptible to corrosion by the saliva and because their retentive force is weak relative to the initial retention offered by mechanical attachments. More recently, magnets have been made from alloys of the rare earth elements samarium and neodymium, which provide stronger magnetic force per unit size. In addition, a new generation of laser-welded containers has improved protection from salivary corrosion. The current resurgence of interest in this type of attachment appears justified because, unlike mechanical attachments, magnets have potential for unlimited durability and might therefore be superior to mechanical ball or bar attachments for the retention of removable prostheses on implants. To date, no long-term prospective trials have been conducted to confirm the clinical durability of this new generation of magnets for retaining dentures on either teeth or implants. The aim of this study was to document initial clinical experiences and levels of satisfaction among edentulous patients treated with mandibular implant-supported overdentures retained using a new generation of rare-earth magnetic attachments. At the outset, all but one of the 17 patients had had several years of experience with implant-supported overdentures. During the first year, the mean overall satisfaction among these 17 patients increased from less than 70 to over 90 out of 100 (standardized visual analogue scale). No unusual difficulties were encountered in rendering the treatment or maintaining the attachments. This report offers preliminary evidence of the excellent potential of these magnets for retaining mandibular implant-supported overdentures.

Oronasal communication caused by a denture with suction cup: a case report

Suction cups, which provide high retention, are not being recommended anymore because of the destructive effect of the negative pressure on the palatal tissues. It is known that dentures with suction cups can cause perforations in the palate. In this case report, an oronasal communication caused by a denture with suction cup in a patient who had previously undergone pleomorphic adenoma excision of the palate is presented. Disadvantages of suction cups are emphasized.

Removable partial dentures without rests

Ever since Bonwill recommended the use of rests on removable partial dentures in 1899, rests have been universally considered inviolate and have gone unchallenged and untested. The author claims that removable partial dentures without rests may not cause the adverse conditions usually predicted, such as gingival stripping, gingival inflammation, mutilated residual ridges, or extensive and rapid resorption of the alveolar ridges. In removable partial dentures made by the author for several patients, the residual ridge remained stable and in physiologic equilibrium when rests were not used. A history of the long-term effect on patients wearing partial dentures with and without rests is presented.

The paradoxes of fixed prosthodontics

(1) The replacement of a missing tooth or teeth by a fixed prosthesis as a preventive device is a paradox. (2) When a missing tooth is replaced by a fixed prosthesis, iatrogenic problems may occur. (3) The problems caused by the fabrication of a fixed partial denture must be recognized and controlled by both the patient and dentist. (4) Concerning the prognosis of any particular fixed prosthesis, we can only predict, from experience, the longevity of the replacement. The acutal life of the replacement is dependent upon the proficiency used in the maintenance procedures and the ability of the dentist to reduce or minimize the iatrogenic factors inherent in any fixed bridge.