Immediate implants in fresh extraction sockets

This clinical report summarized the procedure of immediate implants insertion into fresh extraction sockets. Hydroxylapatite and non- hydroxylapatite coated titanium implants were used in this study; however, it showed no difference in bone to implant contact. This procedure has proved to be successful in eliminating the conventional waiting period after the extraction and speeding the process of ailing teeth replacement. The surgical technique together with other recommendations were discussed in this report

Laboratory evaluation of polyvinyl acrylic copolymer as a relining material for maxillary complete dentures

In this study, the physicomechanical properties [warpage, dimensional accuracy and tensile b and strength] of polyvinyl-acrylic copolymers [10% and 30%] as a relining material were studied in comparison with heat-cured acrylic resin. Scanning electron microscope photomicrographs were produced to study the nature of surface interface between denture base and relining materials. From the present study, it was concluded that dentures made from polyvinyl acrylic copolymer [30%] and relined with the same material [group V] showed the least amount of warpage, and least percentage shrinkage of denture base and artificial teeth in all stages of measurements. Group V showed the highest mean relining materials. The scanning electron microscope [SEM] photomicrographs showed indefinite interface between denture base made from copolymer [30%] relined with copolymer [30]. A difficulty was found during relining of triad visible light-cured [VLC], supplied sheets, which was supported by SEM study that revealed a gag interface between heat- cured acrylic resin and VLC

Clinical evaluation of osseointegrated prosthesis attached to natural teeth using semiprecision attachment

A more complex biomechanical situation is created when a fixed prosthesis is supported by fixture and natural teeth. The natural teeth more but an implant is osseointegrated. When an implant is attached to natural teeth, the movement of the teeth is transmitted to the implant. The prosthesis should be designed to reduce tooth movement, which is harmful to an implant. The use of Minicon semiprecision attachment allows a tooth to move downward. It also gives lateral stability to an implant prosthesis. In this study, six partially edentulous individuals were selected and a total of 22 root from titanium core-vent implants were inserted. The fixed bridge prostheses with Minicon attachment were evaluated clinically [including plaque index, gingival index, probing depth], and radiographically for marginal bone loss

Measurement of abutment teeth movements in mandibular distal extension partial dentures retained by semiprecision attachments

This study measured the amount of tooth movement in two types of semiprecision attachments, intracoronal attachments [Minicon] and extracoronal attachments [Pin Dalbo] in m and ibular distal extension removable partial dentures in case of application of dislodging forces. The m and ibular canines and premolars were prepared to receive two porcelain-fused-to-metal crowns splinted together to decrease the undesirable horizontal forces applied to the teeth. The amount of teeth movements was recorded with dial gauges [0.01 inch] mounted to dial gauge magnetic holders. By the application of displacing forces, the amount of tooth movement was recorded on the premolars and canines while using the two types of semiprecision attachment. It was concluded that Minicon retained partial dentures gave more retention than Pin Dalbo removable partial dentures. Distal abutments were subjected to higher movements in Pin Dalbo attachment removable partial dentures. Minicon retained partial dentures produced more stresses on mesial abutments

Restoration of inadequate occlusal height using etched resin bonded to casting prosthesis

Resin-bonded etched cast partial dentures were used to increase occlusal face height in patients with evidence of m and ibular overclosure. This study was performed in six partially edentulous patients with missing few anterior teeth. They had moderate to severe attrition with about 8-12 mm interocclusal distance. They complained from inability to chew due to a partial loss of teeth and the characteristic appearance of reduced lower face height. The measurements of the occlusal face height from the time of insertion of the resin bonded cast removable partial denture until six months period was recorded

Stresses transmitted to abutment teeth by different clasp assembly designs in post-resection maxilla

There are many controversial statements regarding the philosophy and principles of designing post-resection maxillary cases using metallic framework. In this study, three different clasp designs were used depending on the location of the abutment teeth to be clasped, besides the surface engaged by the retentive arm of clasps either facially or palatally. The stresses induced by different clasp on the abutment teeth were assessed indirectly through the measurement of the amount of strain deflection within the clasp using dial gauge [0.01 inch]. From this study, it can be concluded that a direct correlation between the force applied in the resected side and deflection strain released from the abutment teeth. The obturator design engaging both facial and palatal undercuts provides a better stability

Evaluation of cast round clasps in removable partial denture

Few studies were conducted on the cast round retentive arm regarding their flexibility compared with other forms of retentive arms. This study evaluated the stiffness or the amount of displacing load applied on cast round clasps in premolars and molars with different degrees of undercuts. Three pairs of cast crowns [premolars and molars] were constructed with different undercut [0.25 mm, 0.50 mm and 0.75 mm]. Six pairs of 19 gauge round cast and 3BA-40 half round cast circumferential clasps were constructed on these crowns. It was found that the displacing load acted on the round clasps was less than that acted on half round clasps. A future study is needed to be performed to compare I-bar clasps and the cast circumferential clasps in clinical situation. Other modifications of circumferential clasps are needed to be evaluated in round cast form

mechanical and metallurgical characteristics of recast cobalt chromium alloys

This paper investigated the mechanical properties and microstructure of three commercially used alloys; namely, wironium, wironit and wironit extrahard. The influence of recasting on the different mechanical properties was studied. It was found that the mechanical properties and metallurgic characteristics of three alloys were more or less influenced by recasting. Combining excess used wironium with new alloy and recast reduced the ultimate and yield strength, while the percentage of elongation was slightly improved. Complete recycling of wironit and wironit extrahard had a negligible effect on the ultimate tensile strength of these alloys