Temperature changes of one-piece implants during the setting of acrylic resin temporary crown. The effect of implant diameter. An in vitro study.

The purpose of this work is to evaluate changes in temperature of one-piece titanium implant surface during the setting of acrylic resin temporary crowns and to correlate thermal changes to implant diameter. Thirty-three one-piece implants (ARRP, Alpha-Biotec) were divided into 3 groups according to diameter size (G1=3 mm, G2=3.3 mm, G3=3.6 mm). Implants were mounted on an acrylic glass apparatus. Thermocouples were positioned at the most coronal thread. Lower incisor temporary polycarbonate crowns were filled with 80 µL of self-curing acrylic resin and positioned immediately on the implant abutment. Thermal changes of the implant surface were recorded continuously for 10 min. Data were statistically analyzed using one-way analysis of variance. The mean initial temperature (C0) of groups G1, G2 and G3 was similar (24.79±0.78ºC, 25.26±0.63ºC, 24.97±1.06ºC, respectively). The setting of the acrylic resin temporary crown resulted in a significant increase in the implant surface temperature of all groups. The mean thermal amplitude (ΔC) for groups G1, G2 and G3 were 6.79±1.02ºC, 6.61±0.94ºC, 6.65±1.26ºC, respectively. The mean time to maximum temperature (Tmax) for groups G1, G2 and G3 were 337.38±42.91 sec, 324.69±41.46 sec and 317.98±37.91 sec respectively (P>0.05). Direct application of auto-polymerizing resin to the titanium abutment of one-piece implants significantly increased the cervical implant surface temperature. Implant diameter did not influence the temperature changes.

The effect of mucosal cuff shrinkage around dental implants during healing abutment replacement.

Soft tissue shrinkage during the course of restoring dental implants may result in biological and prosthodontic difficulties. This study was conducted to measure the continuous shrinkage of the mucosal cuff around dental implants following the removal of the healing abutment up to 60 s. Individuals treated with implant-supported fixed partial dentures were included. Implant data--location, type, length, diameter and healing abutments' dimensions--were recorded. Mucosal cuff shrinkage, following removal of the healing abutments, was measured in bucco-lingual direction at four time points--immediately after 20, 40 and 60 s. anova was used to for statistical analysis. Eighty-seven patients (49 women and 38 men) with a total of 311 implants were evaluated (120 maxilla; 191 mandible; 291 posterior segments; 20 anterior segments). Two-hundred and five (66%) implants displayed thick and 106 (34%) thin gingival biotype. Time was the sole statistically significant parameter affecting mucosal cuff shrinkage around dental implants (P < 0.001). From time 0 to 20, 40 and 60 s, the mean diameter changed from 4.1 to 4.07, 3.4 and 2.81 mm, respectively. The shrinkage was 1%, 17% and 31%, respectively. The gingival biotype had no statistically significant influence on mucosal cuff shrinkage (P = 0.672). Time required replacing a healing abutment with a prosthetic element should be minimised (up to 20/40 s), to avoid pain, discomfort and misfit.

[From an immediate implant placement in the post-extraction phase towards immediate loading application: current status].

The fresh extraction socket site in the immediate post-extraction phase possesses unique characteristic wound healing cascade. Marked horizontal and vertical resorption of the edentulous ridge occurred shortly following tooth extraction. In periodontally involved teeth, when partial/full socket wall destruction is evident, the ingrowth of connective tissue into the extraction site is unavoidable leading to a deficient ridge. The use of bone substitute materials aiming to preserve the alveolar ridge by stabilizing the blood clot, thus maintaining the volume of the site and at the same time serves as an osteoconductive scaffold which facilitates continual bone formation. immediate Implant placement, is also a reliable, predictable, and successful procedure. Comparative studies regarding immediate implant placement vs. delayed placement (healed sites) reported similar high survival rate for both procedures. The addition of nonfunctional immediate provisionalization (clearance of all contacts in centric occlusion and during eccentric movements to avoid full functional loading of the implant during healing) achieving an instant aesthetic solution, has been shown to have predictable results. However, a meticulous surgical protocol should be followed. In recent years, an immediate functional loading of cross-arch splinted implants proved to be a reliable and successful approach. Moreover evidence-based data comparing immediate, early and delayed loading failed to show significant difference between those treatment modalities. Apparently, primary stability of implants is an important factor in achieving predictable success. It seems that the addition of controlled loading did not impair those results. A systematic review of the current literature related to this procedure showed a survival rate of over 95% in 34 prospective/retrospective studies. Since clinical parameters were proved to be equal whether implants were placed immediate post-extraction or delayed in a healed alveolar ridge, it appears that cross-arch immediate loading of implants placed in extraction and/or healed edentulous ridges is a predictable procedure with long term stability of the results.

[Crestal core elevation technique--case series and literature review].

Sinus floor augmentation is the most common surgical procedure for gaining bone volume in the posterior maxilla. The purpose of this procedure is to enable implant placement un edentulous ridges. The most common techniques for sinus augmentation are: 1. Bone added osteotome sinus floor elevation (BAOSFE). 2. Crestal core elevation (CCE). 3. Lateral window technique (LWT). Since the early 80's many articles describing the successful use of different augmentation materials for sinus elevation have been published. Although many articles have been published on the lateral window technique and the osteotome technique as described by Summers, few articles have been published on the crestsal core sinus elevation technique. This technique, first described by Summers, includes the use of wide diameter osteotomes and trephine bur with a diameter of 6 m"m. This technique is implemented in situations when the available bone for implant placement is less than 6 m"m , which impairs the possibility of achieving primary stability of the implant. In those cases crestal core elevation is performed and implant placement is postponed 3-8 months later. Modification of the technique described by Summers was published by Fugazzoto, this technique is implemented concomitant with the extraction of the upper molars. The crestal core elevation technique (CCE), which is based on the BAOSFE (Bone Added Osteotome Sinus Floor Elevation), is based on the principle of hydraulic force acting on fluids and particles which transfer the vector of force to all direction, in this case the sinus membrane. The detached core of interradicular bone prior to osteotome placement and malleting significantly reduces surgical trauma to the patient especially in cases where a significant portion of the pre-disease interradicular bone remains. The concomitant placement of particulate material and a membrane at the time of tooth extraction offers the advantage of minimizing if not eliminating significant 3-dimensional alveolar resorption. In this article 3 cases treated using the crestal core elevation technique are presented. Advantages and disadvantages of the technique and indication for use will be discussed.

[Fixed bridgework rehabilitation of an edentulous mandible using different implant systems for superior results--review of the literature and a case report].

Implant therapy, as a modality of treatment, has been reported to establish excellent long-term results for the edentulous patients and the partially dentate patients. It was first consisted on Branemark's protocol in which two-stage approach was claimed to be mandatory for the successful development of osseointegration. However, a one-stage approach was found to produce equal and predictable results. This article discusses the differences between the two systems regarding the alveolar bone response, the microbiological aspect, the peri-implant maintenance and the esthetic outcome. The advantages as well as the disadvantages of each implant system should be taken into consideration when solely used or in combination with the other. A case report demonstrating the combined use of one-stage and two-stage implant systems as was considered to be superior for the treated sites is presented.

[Treatment of multiple recession-type defects in a young patient with esthetic demands].

Treatment of gingival recession has become an important therapeutic issue due to the increasing number of cosmetic demands from patients. Frequently, gingival recessions affect groups of adjacent teeth. In order to optimize the esthetic result all the contiguous recessions should be treated at the same time. The purpose of this article is to compare some techniques of root coverage in a patient with Miller class 1 recessions. A mean of 80% of root exposure was covered using the free gingival graft and free connective tissue graft with repositioned flap compared to 67% using coronally positioned flap over a connective tissue graft. In conclusion, partial root coverage and gingival augmentation with a good esthetic appearance were obtained by a one-step connective tissue graft procedure.

[Single-stage implants in areas of maxillary sinuses that were augmented with allograft. Case reports].

Demineralized freezed dried bone allograft (DFDBA) is known as a bone inductive material, and used widely in periodontal and bone regeneration procedures. DFDBA can also be used for sinus floor augmentation prior or with implant placement. The present manuscript described cases of single-stage implants that were used successfully in areas where the maxillary sinus was augmented with DFDBA simultaneously with implant placement (Case 1) or in a second procedure, 18 months following grafting of the sinus (Case 2). These cases demonstrated the ability to use single-stage implants in the augmented maxillary sinus, in a separated or simultaneous procedure.