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Background: After sinus floor augmentation, a thickening of the sinus mucosa has been described. The aim of the present study was to evaluate the involvement of the maxillary sinus ostium in the edematous processes after a sinus floor augmentation procedure. Methods: Seventy-two cone-beam computerized tomographies (CBSTs) were taken before sinus floor augmentation and after 1 week and 9 months from surgery and analyses. Sinus mucosa thickness and area, ostium diameter and patency, and extension of the post-surgical transient mucosal thickening in relation to the ostium were evaluated on the CBCTs for all three periods. The term "virtual" when referring to sinus mucosa thickness and area was introduced because of the edema and bleeding that both contributed to a transient thickening and additional elevation of the sinus mucosa. Results: The mean virtual thickness of the sinus mucosa was 2.7 ± 4.0 mm, 7.7 ± 7.1 mm, 1.7 ± 2.0 mm before surgery, and after 1 week and 9 months. The virtual mucosa area was 37.2 ± 52.5 mm 2 , 184.5 ± 153.8 mm 2 , and 34.0 ± 50.7 mm 2. The ostium diameter at the three periods evaluated was 1.8 ± 0.5 mm, 1.1 ± 0.6 mm, 1.5 ± 0.8 mm, respectively. Three infundibula (4.2%) were found out of patency before surgery while this number increased to 14 (19.4%) after 1 week. Nine months after surgery, only one infundibulum (1.4%) was out of patency, however, without presenting signs of sinus pathologies. The extension of the mucosal edema on the palatal sinus was reduced after 9 months of healing. Conclusions: One week after sinus floor augmentation, the maxillary sinus mucosa increased in dimensions and in several cases involved the ostium, reducing its diameter and producing a transient loss of patency. After 9 months of healing, the initial conditions were recovered.

Aim The aim of the present study was to evaluate the efficacy on the healing of mechanical decontamination of infected implant surfaces performed with a titanium brush. Methods Mandibular premolars and first molars were extracted bilaterally in six dogs. After 3 months, two unsubmerged implants were installed on both sides of the mandible. Three months later, peri‐implantitis was induced with ligatures for 3 months and then removed. After 1 month, surgical mechanical decontamination of the surfaces was performed either with a rotatory titanium brush or gauzes soaked in saline. Five month later, biopsies were retrieved. Evaluations on X‐rays taken of the mesiodistal plane and on histological slides prepared in a buccal‐lingual plane were performed. Results After the induction of peri‐implantitis, a mean marginal bone loss of 2.6 ± 0.6 mm and 1.9 ± 1.0 mm was observed in the brush and gauze groups by X‐ray, respectively. Five months after treatment, a mean gain of marginal bone of 0.6 mm was obtained in both groups. The mean closures of the vertical and horizontal defects were 0.6 mm and 0.6 mm for the brush group, and 0.8 mm and 0.5 mm for the gauze group, respectively. Histologically, a loss of attachment at the buccal aspect of 2.2 ± 0.9 mm in the brush group and of 2.3 ± 0.5 mm in the gauze group was found. No statistically‐significant differences were found after the treatment. Conclusions Mechanical implant surface decontamination performed with a rotatory titanium brush resulted in a marginal bone level gain, yielding a low content of inflammatory infiltrate close to the marginal bone.

The aim of the experiment was to study the healing at implants installed in site prepared in bone type 1 using different rotation speeds and cooling strategies. The tibiae of twelve sheep were used as experimental sites. Two implant sites were prepared in each tibia using drills either at a high or a mixed speed under irrigation. At the mixed-speed sites, 60 rpm without irrigation were applied for the last drill, the countersink and during implant installation. Biopsies representing the healing after 1, 2, and 6 weeks were obtained and ground sections were prepared. At the histological analyses, after 1 week of healing, no new bone was found at both high- and mixed-speed sites. After 2 weeks of healing, small amounts of newly formed bone were observed in the cortical layer, reaching percentages of 3.6±3.0% at the mixed-speed sites, and of 2.2±1.5% at the high-speed sites. An irrelevant quantity of new bone was seen in the marrow compartments of a few specimens. After 6 weeks of healing, new bone was found in higher quantity, reaching in the cortical compartment 66.9±6.8% and 67.3±17.7% at the mixed- and high-speed sites, respectively. The respective percentages in the marrow compartment were 23.2±13.0% and 30.6±29.2%. No statistically significant differences between high- and mixed-speed groups were found. It was concluded that the use of the last drill and the installation of the implant with or without irrigation yielded similar bone healing and osseointegration.

The formation of color centers induced by irradiation with ArF excimer lasers in CaF(2) crystals was found to depend strongly on the sodium impurity concentration. Sodium-related color centers were generated by two-photon absorption because the slope of the induced absorption coefficient just after irradiation started was proportional to the square of the laser fluence. The saturation absorption also depended on laser fluence, and a photobleaching induced absorption phenomenon was observed. We concluded that the saturation absorption level was determined by the equilibrium between two-photon excitation and one-photon reverse reaction.