Calidad del suelo en huertos de cítricos ecológicos

El mantenimiento de la fertilidad del suelo contemplada globalmente en los aspectos físicos, químicos y biológicos es un factor clave en el sistema de producción ecológica. De ahí que en este sistema agrario se ponga un particular énfasis en la fertilización orgánica. En este estudio se comparan los resultados de varios indicadores de la calidad del suelo registrados en un grupo de 21 parcelas de cítricos ecológicos y otras tantas convencionales. La fertilidad del suelo en los huertos ecológicos resultó superior a la obtenida en los convencionales. Las actividades enzimáticas (fosfatasa alcalina y deshidrogenasa) se revelaron interesantes indicadores de los cambios a corto plazo de la calidad del suelo. La introducción de prácticas de fertilización ecológica con reducción en las aportaciones de insumos no afectó de forma significativa al estado nutritivo de los huertos de cítricos evaluados mediante análisis foliar. El sistema ecológico tampoco afectó de forma significativa al nivel de micorrización ni a las poblaciones de nematodos y hongos nematófagos

Long-term outcomes of short dental implants supporting single crowns in posterior region: a clinical retrospective study of 5-10 years

OBJECTIVE: Aimed to evaluate the long-term clinical and radiographic outcomes of short implants supporting single crowns in the posterior regions. MATERIAL AND METHODS: A retrospective study design was adopted. The clinical and radiographic data of 231 short implants (intra-bony length ≤8 mm) supporting single crowns in 168 patients, were collected after 5-10 (mean 7.22) years' follow-up. Implant and prosthesis failures, peri-implant marginal bone loss, biological and technical complications were evaluated. The influence factors on implant failure were studied. RESULTS: In total 4 implants and 11 prostheses failed. The 10-year (5-year) cumulative survival rate was 98.3% (98.7%) for implant-based analysis and 97.6% (98.2%) for patient-based analysis. The short implants placed in type IV bone yielded more failures than in type I-III and presented a survival rate of 94.0%. The 10-year survival rate of the prostheses was 95.2%. The mean marginal bone loss between implant installation and the 10 years' follow-up visit was 0.63 ± 0.68 mm. The marginal bone loss between the first and 5th year was minimal (0.05 ± 0.10mm and not statistically significant). 18 (7.8%) implants were exposed to biological complications, whereas 29 (12.6%) implants were involved in technical complications. CONCLUSIONS: High survival rates for both the implants and the prostheses could be achieved after 5-10 years for short implants supporting single crowns, without severe marginal bone loss and complications. One may conclude that a single crown supported by a short implant is a predictable treatment modality. However, short implants in type IV bone sites should be applied with caution

Clinical and radiographic study of implant treatment outcome in periodontally susceptible patients: a prospective long-term study

Objectives: To evaluate the implant survival rate, periodontal and radiographic parameters of non-submerged screw implants with two different surfaces (TPS and SLA) in periodontally non-susceptible patients (NSP) and in patients with chronic adult periodontitis (CAP) or with generalized aggressive periodontitis (GAP). Material and methods: In 110 healthy partially edentulous subjects, 68 patients with CAP and 16 patients with GAP, a total of 513 implants were installed and followed for on average 48.1 +/- 25.9 months. Only fixed partial dentures were used as suprastructures. All patients were offered a supportive periodontal maintenance program. Smoking habits, health impairment, plaque score, bleeding on probing (BOP), type of surface, bone score, bone loss on radiographs and the number of failed implants were noted. Results: Implant survival in the NSP and CAP group was 98% and 96% after 140 months (NS), but only 80% after 100 months in the GAP group (P=0.0026). The overall rate of implant loss was 4.7%, but 15.25% in the GAP group (6/16 patients). The average marginal bone loss for all implants was 0.12 +/- 0.71 mm on the mesial side and 0.11 +/- 0.68 mm on the distal side. Bone loss/year was 0.08 +/- 0.31 and 0.07 +/- 0.3 mm in the NSP group, but 0.17 +/- 0.2 and 0.17 +/- 0.19 mm in the GAP group. Only in the GAP group, was bone loss significantly related to BOP, age, inflammation, presence of plaque, probing depth. Implants with a TPS surface had a lower survival than implants with an SLA surface (93% vs. 97%; P=0.06), especially in the GAP group (80% vs. 83%; P=0.005). Smoking habits had a significant influence on implant survival only in the GAP group (P=0.07), declining in current smokers to 63%, and to 78% in former smokers. Overall, impaired general health had no significant influence (P=0.85). However, impaired health further reduced implant survival in the GAP group (survival: 71%). In a statistical model to predict the chance for implant failing, only periodontal classification (P=0.012) and implant surface type (P=0.027) were significant. Conclusion: Periodontally healthy patients and patients with CAP show no difference in peri-implant variables and implant survival rate, but patients with GAP have more peri-implant pathology, more marginal bone loss and a lower implant survival implant rate. SLA surface had a better prognosis than the TPS surface