RESUMEN

BACKGROUND: A thickening of the sinus mucosa is observed after sinus floor augmentation. The objective of this retrospective study was to evaluate the influence of the presence of septa in the dimensional variation and ostium involvement over time of the Schneiderian mucosa after sinus floor augmentation. MATERIALS AND METHODS: Fifteen sinuses with septa (septa group) and 15 without (control group) were selected. CBCTs taken before surgery, and were analyzed after 1 week and after 9 months. Schneiderian membrane thickness changes over time and involvement of the ostium were evaluated. RESULTS: Four perforations occurred in the septa group and none in the control group. After 1 week of healing, the sinus mucosa thickness increased in height by 5.7 mm and 7.1 mm in the septa and control groups, respectively. In this period, the patency of the ostium decreased in both groups, and three infundibula were obstructed in the septa group, and five in the control group. The mucosa was thicker and the edema was closer to the ostium in the control compared to in the septa group. After 9 months of healing, the dimensions regressed to normal pattern and no obstruction of the infundibula were observed. No statistically significant differences were found between septa and control groups. CONCLUSIONS: after one week of healing, the sinus mucosa increased in dimensions in both septa and control groups. However, the sinus mucosa presented a tendency of being thicker and closer to the ostium, resulting in a higher number of infundibula obstructions, in the control group compared to in the septa group. After 9 months, the sinus mucosa regressed to normal dimensions and no obstructions of the infundibula were observed in any group.

RESUMEN

PURPOSE: To evaluate the influence on healing of the bony window elevated inward in the sinus cavity as a cortical bone graft. MATERIALS AND METHODS: Eighteen rabbits were included in the experiment. At the test sites (bony window), the antrostomy was prepared and the remaining bony window was elevated together with the sinus mucosa. At the control sites, the bony window was gently detached before the sinus mucosa elevation and discarded. The space obtained was grafted with deproteinized bovine bone mineral (DBBM). A collagen membrane was positioned on the antrostomy at both sides. The rabbits were euthanized after 2, 4, and 8 weeks in groups of six each. Histologic analyses in different regions of the elevated space were carried out, and a Wilcoxon test was used to estimate differences. Microcomputed tomography (microCT) analyses were also performed. RESULTS: After 2 weeks of healing, higher proportions of new bone were found in the test group compared with the control group due to the higher amount of bone formed in the region subjacent to the sinus mucosa. In this region, higher amounts of new bone were also found in the test group after 4 (P = .028) and 8 weeks of healing (P = .345). After 8 weeks of healing, the percentage of new bone was higher at the control sites compared with the test sites, with the proportions being 25.4% ± 3.2% and 21.3% ± 6.1%, respectively. In this period of evaluation, the bony window contributed with 20.1% ± 5.3% of vital bone in the test group. A fraction of 60.4% ± 10.8% of its surface was surrounded by new bone. In the microCT analysis, after 8 weeks of healing, fractions of 22.3% ± 1.6% and 22.2% ± 0.7% of bone were found in the test and control groups, respectively. CONCLUSION: The presence of the bony window positively influenced the healing in the elevated space, especially in the submucosa region. The bony window was vital and incorporated into newly formed bone.

Asunto(s)

RESUMEN

PURPOSE: To evaluate the influence of bioactivation with argon plasma of a xenograft used as graft material for sinus floor augmentation. MATERIALS AND METHODS: Sinus floor elevation was performed in 20 rabbits using a deproteinized bovine bone mineral as graft material. The xenograft used in the test sites was bioactivated with argon plasma (plasma group), while that used in the control sites was left untreated (control group). Collagen membranes were used to cover the antrostomy. The rabbits were euthanized after 2 and 10 weeks, in groups of 10 each. A histomorphometric analysis was performed in various regions of the elevated space. RESULTS: After 2 weeks of healing, a similar pattern of healing was observed in both groups. New bone fractions were 5.2% ± 2.9% in the plasma group and 5.0% ± 3.5% in the control group (P = .795). In this period, higher amounts of new bone were found in the region close to the sinus bone walls. After 10 weeks of healing, the amounts of new bone within the elevated space increased to 23.5% ± 7.0% and 21.3% ± 7.3% (P = .176) in the plasma and control groups, respectively. The only statistically significant difference was found in the central region, with 20.4% ± 9.7% in the plasma group and 13.2% ± 10.5% in the control group (P = .037). CONCLUSION: The bioactivation of a xenograft using argon plasma improved bone formation within an augmented sinus, especially in the central regions, far from osteogenic sources.

Asunto(s)

RESUMEN

AIM: To evaluate histologically the healing of mini-implants installed after sinus floor elevation using a lateral approach and placing the antrostomy at different level from the sinus floor. MATERIAL AND METHODS: Sinus floor elevation using a lateral approach was performed in 24 healthy volunteers. The antrostomy was randomly placed either close to the base of the sinus floor (group base) or at about 3-4 mm cranially to it (group standard). After 6 months of healing, mini-implants were installed within the grafted region, through the alveolar crest. Three months later, biopsies were collected. RESULTS: Sixteen biopsies from 16 patients were available for histological analyses. The new bone reached fractions of 40.9 ± 11.9% and 48.5 ± 20.1% at the base and standard groups, respectively (p = 0.208). Xenograft particles were found in contact with the implant surface at percentages of 12.1 ± 11.0% in the base group, and 15.9 ± 23.7% in the standard group (p = 0.674). CONCLUSIONS: Based on the present study, the choice of one or the other position of antrostomy did not influence significantly the outcome and, therefore, should be left to the preference of the surgeon.

Asunto(s)

RESUMEN

PURPOSE: To evaluate the dimensional variations after elevation of the maxillary sinus floor and the healing of the antrostomy left unprotected or protected by a collagen membrane. MATERIALS AND METHODS: Twenty patients were included in the study. After the elevation of the sinus mucosa, natural bovine bone was grafted into the elevated space. In 10 randomly selected patients, a native collagen membrane made of porcine corium was placed on the antrostomy (membrane group). In the other 10 patients, the antrostomy was left uncovered (no-membrane group). Cone beam computed tomography (CBCT) images were taken for all patients before surgery (T0), 1 week after sinus floor augmentation (T1), and after 9 months of healing (T2), and evaluations of dimensional variations over time of soft and hard tissues were performed. RESULTS: At T1, the elevation of the sinus floor in the middle aspect was 12.5 ± 3.8 mm and 11.9 ± 3.6 mm in the membrane and no-membrane groups, respectively. At T2, the reduction in height of the elevated space was 0.6 ± 0.9 mm and 0.8 ± 0.8 mm in the membrane and no-membrane groups, respectively. The elevated area decreased between ~10% and 11% in the membrane group and between ~15% to 20% in the no-membrane group. However, no statistically significant differences were found. CONCLUSION: The use of a collagen membrane to cover the antrostomy after sinus floor elevation did not produce significant clinical effects on dimensional variations over time.

Asunto(s)

RESUMEN

AIM: To study the influence of a collagen membrane placed subjacent to the sinus mucosa on the dimensional changes of augmented maxillary sinus floor. METHODS: Twenty patients were recruited in the study and randomly assigned to two groups. After the elevation of the maxillary sinus mucosa, a collagen membrane with standardized dimensions was placed at the test sites subjacent to the sinus mucosa and the elevated space was filled with a xenograft, both at test and control sites. A collagen membrane was then used to cover the antrostomy at both sites, and sutures were applied to close the wounds. Cone beam computed tomographies (CBCTs) were taken for all patients before surgery (T0), after 1 week from sinus floor augmentation (T1), and after 9 months of healing (T2). Dimensional changes over time of soft and hard tissues were evaluated on the CBCTs. RESULTS: After 1 week of healing, the sinus floor was elevated by 10.0 ± 2.8 mm and 10.6 ± 2.5 mm at the no-membrane and membrane groups, respectively. After 9 months of healing, a similar reduction of the height was observed in both groups, providing a total vertical augmentation of 8.6 ± 2.8 mm at the no-membrane sites and 9.1 ± 3.1 mm at the membrane sites. After 9 months of healing, the hard tissues subjacent to the sinus mucosa appeared to be partially corticalized in three patients in the no-membrane group and in six patients in the membrane group. CONCLUSIONS: The use of collagen membranes subjacent to the sinus mucosa did not influence the dimensional variations of the augmented regions and the clinical outcomes after 9 months of healing also in absence of perforations.

RESUMEN

A 69-year-old man who had been hospitalized with acute coronary syndrome (ACS), underwent urgent percutaneous coronary intervention. In the subacute phase, he developed sudden chest pain and hemodynamic deterioration, and urgent coronary angiogram showed multiple coronary artery spasms. The discontinuation of beta-blocker treatment and the administration of a calcium antagonist helped prevent angina attacks. In Japanese patients who tend to have coronary artery spasm, the routine administration of beta-blockers for post-ACS patients with a preserved left ventricular systolic function should be considered carefully.

Asunto(s)

Asunto(s)

RESUMEN

A 66-year-old man, who had been diagnosed with deep venous thrombosis (DVT), and who was treated with a vitamin K antagonist (VKA) and who had undergone the implantation of an inferior vena cava filter, was admitted due to an exacerbation of DVT. VKA was administered again; however, the patient's DVT worsened. Further examinations revealed colon cancer, which led to a diagnosis of Trousseau's syndrome. The regression of the thrombi was confirmed after the administration of heparin and the resection of the tumors. Trousseau's syndrome should always be kept in mind when patients present with refractory venous thrombosis. The administration of heparin, and cancer control are necessary for the effective treatment of thrombosis in such cases.

Asunto(s)