Antonio Aguilar-Salvatierra

Evaluation of Primary Stability of Self-Tapping and Non-Self-Tapping Dental Implants. A 12-Week Clinical Study

PURPOSE The aim of this study was to investigate the relationship between surgical techniques and implant macro-design (self-tapping/non-self-tapping) for the optimization of implant stability in the low-density bone present in the posterior maxilla using resonance frequency analysis (RFA). MATERIALS AND METHODS A total of 102 implants were studied. Fifty-six self-tapping BlueSkyBredent® (Bredent GmbH&Co.Kg®, Senden, Germany) and 56 non-self-tapping Standard Plus Straumann® (Institut Straumann AG®, Waldenburg, Switzerland) were placed in the posterior segment of the maxilla. Implants of both types were placed in sites prepared with either lateral bone-condensing or with bone-drilling techniques. Implant stability measurements were performed using RFA immediately after implant placement and weekly during a 12-week follow-up period. RESULTS Both types of implants placed after bone condensing achieved significantly higher stability immediately after surgery, as well as during the entire 12-week observation period compared with those placed following bone drilling. After bone condensation, there were no significant differences in primary stability or in implant stability after the first week between both implant types. From 2 to 12 postoperative weeks, significantly higher stability was shown by self-tapping implants. After bone drilling, self-tapping implants achieved significantly higher stability than non-self-tapping implants during the entire follow-up period. CONCLUSIONS The outcomes of the present study indicate that bone drilling is not an effective technique for improving implant stability and, following this technique, the use of self-tapping implants is highly recommended. Implant stability optimization in the soft bone can be achieved by lateral bone-condensing technique, regardless of implant macro-design.

Denosumab and osteonecrosis of the jaw. A systematic analysis of events reported in clinical trials

OBJECTIVES The aims of this meta-analysis were (i) to perform a systematic review of the relation between treatment with denosumab and the incidence of osteonecrosis of the jaw (ONJ) and (ii) to obtain information on dosage, first event apparition, and treatment approaches for patients with ONJ related to denosumab. MATERIALS AND METHODS A systematic review and meta-analysis of relevant literature was performed in the PubMed, MEDLINE, Embase, and Cochrane databases, identifying randomized clinical trials that evaluate the adverse effects of denosumab. The overall incidence rates and 95% confidence intervals (CI) for ONJ were calculated employing fixed- and random-effects models, according to the heterogeneity of the studies included. RESULTS A total of 8963 patients with a variety of solid tumors reported in seven randomized controlled trials (RCTs) were included in the systematic analysis. The overall incidence of ONJ in patients with cancer receiving denosumab was 1.7% [95% CI: 0.9-3.1%]. The use of denosumab was associated with a significantly increased risk of ONJ in comparison with bisphosphonates (BPs)/placebo treatment (RR 1.61, 95% CI: 1.05-2.48, P = 0.029). Subgroup analysis based on controlled therapies demonstrated an increased risk of ONJ in denosumab therapy, when compared with BPs (RR 1.48, 95% CI: 0.96-2.29, P = 0.078) or placebo (RR 16.28, 95% CI: 1.68-158.05, P = 0.017). Similar results were observed for prostate cancer (RR 3.358, 95% CI: 1.573-7.166, P = 0.002). CONCLUSIONS Denosumab combined with risk factors such as dental extraction, poor oral hygiene, use of removable apparatus, and chemotherapy may favor the development of ONJ.

THE EFFICACY OF A TOPICAL SIALOGOGUE SPRAY CONTAINING 1% MALIC ACID IN PATIENTS WITH ANTIDEPRESSANT‐INDUCED DRY MOUTH: A DOUBLE‐BLIND, RANDOMIZED CLINICAL TRIAL

One of the most important antidepressants side effects is dry mouth. The aim of this study was to evaluate the clinical efficacy of a topical sialogogue spray containing 1% malic acid on patients affected by dry mouth caused by antidepressants drug.

Effectiveness of malic acid 1% in patients with xerostomia induced by antihypertensive drugs.

Objectives: Assessing the clinical effectiveness of a topical sialogogue on spray (malic acid, 1%) in the treatment of xerostomia induced by antihypertensive drugs. Study Design: This research has been carried out through a randomized double-blind clinical trial. 45 patients suffering from hypertensive drugs-induced xerostomia were divided into 2 groups: the first group (25 patients) received a topical sialogogue on spray (malic acid, 1%) whereas the second group (20 patients) received a placebo. Both of them were administered on demand for 2 weeks. Dry Mouth Questionnaire (DMQ) was used in order to evaluate xerostomia levels before and after product/placebo application. Unstimulated and stimulated salivary flows rates, before and after application, were measured. All the statistical analyses were performed by using SPSS software v17.0. Different DMQ scores at the earliest and final stage of the trial were analysed by using Mann-Whitney U test, whereas Student’s T-test was used to analyse salivary flows. Critical p-value was established at p<0.05. Results: DMQ scores increased significantly (clinical recovery) from 1.21 to 3.36 points (p<0.05) after malic acid (1%) application whereas DMQ scores increased from 1.18 to 1.34 points (p>0.05) after placebo application. After two weeks of treatment with malic acid, unstimulated salivary flow increased from 0.17 to 0.242 mL/min whereas the stimulated one increased from 0.66 to 0.92 mL/min (p<0.05). After placebo application unstimulated flow ranged from 0.152 to 0.146 mL/min and stimulated flow increased from 0.67 to 0.70 mL/min (p>0.05). Conclusions: Malic acid 1% spray improved antihypertensive-induced xerostomia and stimulated the production of saliva. Key words:Xerostomia, hyposialia, malic acid, antihypertensive drugs.

Marginal bone loss evaluation around immediate non‐occlusal microthreaded implants placed in fresh extraction sockets in the maxilla: a 3‐year study

OBJECTIVE To evaluate marginal bone loss over 3 years around immediate microthreaded implants placed in the maxillary anterior/esthetic zone and immediately restored with single crowns. MATERIAL AND METHODS Seventy-one implants (with microthreads up to the platform--rough surface body and neck, internal connection and platform switching) were placed in fresh extraction sockets in the maxillary arches of 30 men and 23 women (mean age 37.85 ± 7.09 years, range 27-60). All subjects had at least 3 mm of soft tissue to allow the establishment of adequate biologic width and to reduce bone resorption. Each patient received a provisional restoration immediately after implant placement with slight occlusal contact. Mesial and distal bone height was evaluated using digital radiography on the day following implant placement (baseline) and after 1, 2, and 3 years. Primary stability was measured with resonance frequency analysis. RESULTS No implants failed, resulting in a cumulative survival rate of 100% after 3 years. Marginal bone loss from implant collar to bone crest measured at baseline (peri-implant bone defect at the fresh extraction socket) and after 3 years was 0.86 mm ± 0.29 mm. Mesial and distal site crestal bone loss ranged from 3.42 mm ± 1.2 mm at baseline to 3.51 mm ± 1.5 mm after 3 years (P = 0.063) and from 3.38 mm ± 0.9 mm at baseline to 3.49 mm ± 0.9 mm after 3 years, respectively (P = 0.086). CONCLUSIONS This prospective study found minimal marginal bone loss and a 100% implant survival rate over the 3-year follow-up for microthreaded immediate implants subjected to immediate non-occlusal loading.

Histological and Histomorphometric Evaluation of Zirconia Dental Implants Modified by Femtosecond Laser versus Titanium Implants: An Experimental Study in Fox Hound Dogs

PURPOSE This study applied femtosecond laser technology to zirconia dental implants (Bredent GmbH & Co.KG, Senden, Germany) to generate a surface texture of microgrooves over the entire intraosseous surface, analyzing its behavior in an in vivo model in comparison with titanium implants with sandblasted and acid-etched surfaces. MATERIALS AND METHODS The study used six American Fox Hound dogs. Each received four implants per hemi-mandible, making a total of eight implants per animal. The 48 immediate loaded implants were divided into two groups of 24 titanium implants (control group) and 24 zirconia implants (study/test group), distributed randomly. Bone-to-implant contact (BIC) values and crestal resorption were determined at 1 and 3 months, also measuring calcium, phosphorous, and carbon concentrations by means of energy dispersive x-ray. RESULTS BIC percentages after 30 days were 51.36% for titanium implants and 44.68% for zirconia implants. After 90 days, values increased to 61.73% in titanium and 47.94% in zirconia implants. After 30 days, there was more crestal bone lost in the titanium group (0.77 mm) compared with the zirconia group (0.01 mm). After 90 days, zirconia implants showed greater marginal bone resorption (1.25 mm) compared with the titanium group (0.37 mm). CONCLUSIONS The present study shows that zirconia implants with modified surfaces can produce good osseointegration values when compared with titanium implants in terms of BIC and crestal bone resorption at 1 and 3 months.

Bone remodeling at implants with different configurations and placed immediately at different depth into extraction sockets. Experimental study in dogs

OBJECTIVES This study evaluated the effect of implant macrodesign and position, related to the bone crest, on bone-to-implant contact (BIC) and crestal bone (CB) in immediate implants. MATERIAL AND METHODS The study comprised of six foxhound dogs in which 48 immediate implants were placed. Three types of implants from the same manufacturer with similar surface characteristics but different macrodesigns were randomly placed: Group A (external hex with no collar microthreads), Group B (internal hex and collar microrings), and Group C (internal conical connection and collar microrings). Half of the implants were placed leveled with the bone crest (control) and the remaining, 2 mm subcrestally (test). Block sections were obtained after 12 weeks and processed for mineralized ground sectioning. Statistical analysis consisted of nonparametric Friedman and Wilcoxon test. RESULTS All implants were clinically stable and histologically osseointegrated. Mean BIC percentage within the control group was as follows: A: 42.52 ± 8.67, B: 35.19 ± 18.12, and C: 47.46 ± 11.50. Within the test group: A: 47.33 ± 5.23, B: 48.38 ± 11.63, and C: 54.88 ± 11.73. Differences between each subgroup in the test and the control groups were statistically significant. BIC was statistically significantly higher in the test (50.588 ± 8.663) than in the control (43.317 ± 9.851) group. Within both groups, differences between group C and the other 2 were statistically significant. Distance from the implant shoulder to the buccal CB was statistically significantly larger in the control than in the test group and between subgroups B and C in the control and test groups. Within the test groups, relative bone gain was noticed. CONCLUSIONS Subcrestal immediate implant positioning may lead to a relatively reduced CB resorption and increased BIC. Implants macrodesign with crestal microrings may enhance BIC in post-extraction implants.

Influence of the implant design on osseointegration and crestal bone resorption of immediate implants: a histomorphometric study in dogs

PURPOSE The aim of this study was to evaluate bone-to-implant contact after immediate implant placement at different levels in relation to crestal bone in American foxhound dogs. MATERIALS AND METHODS The mandibular second, third, and fourth premolars of six American foxhound dogs were extracted bilaterally. Randomly, three immediate implants were placed in the hemimandible of each dog at the bone crest (control group) or 2 mm subcrestally (test group). Three dogs were allowed an 8-week healing period; the other three were left a 12-week healing period. After healing periods, histomorphometric analyses of the specimens were carried out to measure BIC values and bone remodeling. RESULTS All implants healed uneventfully and were available for histological analysis. The total BIC mean values were 44.52% (± 8.67) and 39.50% (± 9.25) at 8 and 12 weeks, respectively, for the control group, and 47.33% (± 5.23) and 53.85% (± 4.21) at 8 and 12 weeks after healing for the test group, respectively. There was observed less bone resorption in the group of implants placed subcrestally. CONCLUSION Our findings suggest that less resorption may be expected when implants are inserted 2 mm subcrestally. Moreover, higher BIC values in the group of subcrestal implants were found.

Peri‐implant bone organization surrounding zirconia‐microgrooved surfaces circularly polarized light and confocal laser scanning microscopy study

OBJECTIVES To study the peri-implant bone organization pattern of immediately loaded (IL) zirconia implants with microgrooved surfaces. MATERIALS AND METHODS Forty-eight dental implants of 4 mm diameter and 10 mm length were inserted after two months postextraction healing in the edentulous mandible of six dogs. Three groups of sixteen implants were used, titanium implants (Control), zirconia implants (test A), and zirconia-microgrooved implants (test B), which were loaded immediately. After 4-month healing period, implant-bone samples were processed and analyzed by circularly polarized light (CPL) and confocal laser scanning microscopy (CLSM) in two regions of interest ROI1 (to evaluate the interthread bone) and ROI2 (to evaluate the bone adjacent to the threads) of 1 mm thickness × 10 mm length each one. RESULTS Bone organization differs near to the test B, compared with test A and control surfaces, active remodeling was detected surrounding test B implants, with alternancy of organized zones, meanwhile controls and test A areas showed organized areas mainly at 2 mm of implant surfaces. Transverse collagen fibers were significatively higher at ROI1 for test B implants (60.34 ± 4.34%), compared with controls (47.25 ± 3.51%) and test A (43.78 ± 2.78%) groups (P < 0.05). Meanwhile, it was not found any significant difference between groups in ROI2 (P > 0.05). CLSM confirmed the presence of collagen mineralized matrix inside microgrooves of test B groups. 3D reconstruction showed blood vessels in direct contact with the implant surfaces of all groups and bone and blood vessels penetration inside the microgrooves in test B group. CONCLUSION The organized pattern of the microgrooved surfaces is able to induce transverse collagen fiber microenvironment reaction to the load, being positive to promote and to maintain the bone remodeling; in addition blood vessels and bone cells are able to penetrate microgrooved surfaces.

Update of Surgical Techniques for Maxillary Sinus Augmentation: A Systematic Literature Review.

Objective:A wide range of surgical techniques are available for maxillary sinus augmentation. This review aimed to determine which techniques have achieved the highest success rates and so offer the greatest predictability. Materials and Methods:A systematic literature review was performed using the PubMed, MEDLINE, and Scopus databases, identifying clinical trials that assessed different surgical techniques for maxillary sinus augmentation, and registered the success rates of subsequent implant placement. Results:A total of 40 articles described clinical studies involving different maxillary sinus augmentation procedures with follow-up periods of at least 6 months after dental implant placement. Implant success rates varied between 94% and 100% during the follow-up periods. Conclusion:A wide variety of clinical techniques are available for maxillary sinus augmentation; the choice of the technique will depend chiefly on the characteristics of the edentulous site, which will permit or prevent the placement of the implant at the moment of sinus augmentation surgery.