Effect of implant macro-design on primary stability: A prospective clinical study.

BACKGROUND: Implant restorations have become a high predictable treatment option. Several caracteristics such as surgical technique and implant design can influence the treatment outcomes. The aim of the present study was to evaluate the influence of implant macro-design on primary stability measured with resonance frequency analysis (RFA) and insertion torque (IT). Material and Mehods: A total of 47 implants divided in two groups: Test group (TI): 22 Tapered MIS® Seven implants; Control group (CI): 25 cylindrical Astra® Osseospeed implants. All implants were inserted following the manufacturers' standard protocols. Implant primary stability was measured at the moment of implant placement by registering insertion torque values (ITv) and ISQ values by means of Osstell™ Mentor (ISQv) (Integration Diagnostic Ltd., Goteborg, Sweden). RESULTS: In the mandible, mean ISQv for tapered implants (TI) was 71.67±5.16 and for cylindrical implants (CI) 57.15±4.83 (p=0.01). Mean insertion torque was 46.67±6.85 Ncm for TI and 35.77±6.72 Ncm for CI (p=0.01). In the maxilla, mean ISQ was 67.2±4.42 for tapered implants and 49.17±15.30 for cylindrical implants (p=0.01). Mean insertion torque for TI was 41.5±6.26 Ncm and for CI 39.17±6.34 Ncm (p>0.05). For tapered implants, no correlation could be found between implant diameter and primary stability. But for cylindrical implants there was a statistically significant correlation between implant diameter and primary stability: ITv (p=0.03); ISQv (p=0.04). CONCLUSIONS: Within the limits of the present study, tapered shaped implants achieve higher primary stability measured through ISQ and insertion torque values. Moreover, for cylindrical implants positive correlation has been established between implant diameter and primary stability.

Are there height-dependent differences in subclinical vascular disease in hypertensive patients?

The aim of the study was to determine whether there are differences in subclinical vascular disease (SVD) in hypertensive patients in relation to height. A total of 922 hypertensive, newly diagnosed, treatment-naive patients were included. Physical examination was conducted, with renal function, electrocardiography, and retinography. Patients were distributed according to quartiles of height and sex. Multivariate analysis adjusted for age, sex, and body mass index showed an association between height above the mean and fasting glucose (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.02-1.06), high-density lipoprotein cholesterol (OR, 0.96; CI, 0.92-0.99), triglycerides (OR, 1.07; CI, 1.01-1.15), and left ventricular hypertrophy (LVH) (OR, 1.57; CI, 1.10-2.24). The authors found an inverse association between arteriole-to-venule ratio and height above the mean (OR, 0.97; CI, 0.94-0.99). There are differences in the SVD of hypertensive patients in relation to height. Tall stature is associated with LVH while short stature is associated with increased microvascular involvement. Detection of SVD in hypertensive patients should consider the height.

A novel trephine design for sinus lift lateral approach. Case report.

Various techniques are described in the literature, either by crestal or lateral approach. Sinus augmentation has a high percentage of success, but presents a number of intraoperative and postoperative complications. The most frequent complication is the Schneiderian membrane perforation with a percentage of perforations between 11% and 56% according to authors. The aim of this study is to describe another membrane approach technique for the sinus lateral wall osteotomy that minimizes the risk of Schneiderian membrane perforation. We present a case of a 50 year old patient attended the University Dental Clinic (UDC) of International University of Catalonia for implant and crown treatment due to the loss of a right maxillary first molar. To insert an implant in position 1.6 a computerized tomography (CT) was requested to determine with greater accuracy the quantity of residual crestal bone. It showed a height of 5 mm and width of 8 mm. The lateral osteotomy was performed with a (SLA KIT®-Neobiotech) trephine mounted in the same implant handpiece with which the field for the implant and the implant itself were prepared. It can be concluded that in the case described, the use of trephine drills of the SLA system mounted in a handpiece allows better access to lateral approach due to its perpendicular position relative to the sinus wall minimizing the membrane perforation risk.

Relation between bone density and primary implant stability.

AIMS: This study aims to relate bone density in Hounsfield units (Hu) with the primary implant stability measured by insertion torque (Ncm) and resonance frequency analysis (ISQ). MATERIALS AND METHODS: Ten patients were included in this study. A total of 54 implant sites were provided from 10 computerized tomography scans. The computerized tomography scan was used for the preoperative evaluation of bone density for each patient. The bone mean density around planned implants was determined with Physioplanet TM software. Bone quality according resistance to drilling, insertion torque and resonance frequency measurements were recorded. RESULTS: A statistically significant relationship was observed between bone quality density and location with ISQ values. CONCLUSIONS: This research demonstrates a strong relationship between the bone density values from computerized tomography and the location in the maxillaries. A correlation exists between bone quality, according to the Lekholm & Zarb classification, and Hu computerized tomography values. The primary implant stability measured with resonance frequency analysis depends on bone density values, bone quality and implant location.