Probiotics diminish the post-operatory pain following mandibular third molar extraction: a randomised double-blind controlled trial (pilot study).

The aim of this study was to investigate the effect of a probiotic in preventing infections after third molar surgery. Thirty-eight patients were consecutively enrolled to a double-blind randomised placebo-controlled trial. Patients were asked to take one tablet two times a day containing a mixture of Levilactobacillus brevis CECT7480 (KABP-052) and Lactoplantibacillus plantarum CECT7481 (KABP-051) or placebo for the first post-intervention week. The primary outcome was the postoperative infection rate. Secondary outcomes included swelling, eating difficulties and postoperative pain recorded by the patient using a visual analogue scale (VAS) during the first postoperative week. No statistically significant difference in the infection rate between the groups was found; with only three cases of infections reported (one in the probiotic group and two in the placebo group) on the first week. Compared to placebo, treatment with the probiotic showed a significantly higher reduction in pain and eating difficulties scores at 5, 6 and 7 days post-surgery. Swelling values were not significantly different between the groups at any time point. The findings of this pilot study justify a larger study to clarify the possible role of these bacterial strains on the post-operative pain management following third molar surgery.

Slow drilling speeds for single-drill implant bed preparation. Experimental in vitro study.

AIMS: To evaluate the real-time bone temperature changes during the preparation of the implant bed with a single-drill protocol with different drill designs and different slow drilling speeds in artificial type IV bone. MATERIALS AND METHODS: For this experimental in vitro study, 600 implant bed preparations were performed in 10 bovine bone disks using three test slow drilling speeds (50/150/300 rpm) and a control drilling speed (1200 rpm). The temperature at crestal and apical areas and time variations produced during drilling with three different drill designs with similar diameter and length but different geometry were recorded with real-life thermographic analysis. Statistical analysis was performed by two-way analysis of variance. Multiple comparisons of temperatures and time with the different drill designs and speeds were performed with the Tukey's test. RESULTS: T Max values for the control drilling speed with all the drill designs (D1 + 1200; D2 + 1200; D3 + 1200) were higher compared to those for the controls for 11 ± 1.32 °C (p < 0.05). The comparison of T Max within the test groups showed that drilling at 50 rpm resulted in the lowest temperature increment (22.11 ± 0.8 °C) compared to the other slow drilling speeds of 150 (24.752 ± 1.1 °C) and 300 rpm (25.977 ± 1.2 °C) (p < 0.042). Temperature behavior at crestal and apical areas was similar being lower for slow drilling speeds compared to that for the control drilling speed. Slow drilling speeds required significantly more time to finish the preparation of the implant bed shown as follows: 50 rpm > 150 rpm > 300 rpm > control (p < 0.05). CONCLUSIONS: A single-drill protocol with slow drilling speeds (50, 150, and 300 rpm) without irrigation in type IV bone increases the temperature at the coronal and apical levels but is below the critical threshold of 47 °C. The drill design in single-drill protocols using slow speeds (50, 150, and 300 rpm) does not have an influence on the thermal variations. The time to accomplish the implant bed preparation with a single-drill protocol in type IV bone is influenced by the drilling speed and not by the drill design. As the speed decreases, then more time is required.

Osseoinductive elements around immediate implants for better osteointegration: a pilot study in foxhound dogs.

OBJECTIVE: The aim of this study was to evaluate the effects on osseointegration of topical applications of melatonin vs. vitamin D over surfaces of immediate implants. MATERIALS AND METHODS: Mandibular premolar distal roots (P2 , P3 , P4 ) were extracted bilaterally from six American Foxhound dogs. Three conical immediate implants were randomly placed bilaterally in each mandible. Three randomized groups were created: melatonin 5% test group (MI), vitamin D 10% test group (DI), and Control group implants (CI). Block sections were obtained after 12 weeks and processed for mineralized ground sectioning. Bone-to-implant contact (total BIC), new bone formation (NBF), inter-thread bone (ITB), and histological linear measurements (HLM) were assessed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. Total BIC values were 49.20 ± 3.26 for the MI group, 49.86 ± 1.89 for DI group and 45.78 ± 4.21 for the CI group (P < 0.018) with statistically significant difference between the three groups. BIC percentage were 42.44 ± 2.18 for MI, 44.56 ± 1.08 for DI, and 41.95 ± 3.34 for CI groups respectively (P > 0.05). Inter-thread bone formation values were MI 17.56 ± 2.01, for DI 19.87 ± 0.92, and CI 14.56 ± 1.24 (P > 0.05). Statistically significant differences in peri-implant new bone formation were found between the three groups: MI 28.76 ± 1.98, DI 32.56 ± 1.11 and CI 25.43 ± 4.67, respectively (P < 0.045). Linear measurements showed that the MI group showed significantly less lingual crestal bone loss (CBL) (MI 0.59 ± 0.71), compared to DI (0.91 ± 1.21) and CI (0.93 ± 1.21) (P < 0.042), and less lingual peri-implant mucosa (PIM) (MI 3.11 ± 1.34),(DI 3.25 ± 0.18 compared with CI 3.54 ± 1.81 (P = 0.429). Linear measurements of buccal CBL showed significantly less buccal bone loss in test DI (0.36 ± 0.12) than CI (1.34 ± 1.23) and MI (1.11 ± 1.38) (P = 0.078). CONCLUSIONS: Within the limitations of this animal study, topical applications of 5% Melatonin or 10% vitamin D improved bone formation around implants placed immediately after extraction and helped to reduce CBL after 12 weeks osseointegration.

Do topical applications of bisphosphonates improve bone formation in oral implantology? A systematic review.

BACKGROUND: The aim of this systematic literature review was to evaluate the feasibility of topical bisphosphonate application for preserving/enhancing alveolar bone in oral implantology. MATERIAL AND METHODS: An electronic search was conducted in the PubMed/Medline, EMBASE, Scopus, Web of knowledge, and Google-Scholar databases for articles dated from January 2000 to December 2016. Two reviewers assessed the quality of the studies independently. RESULTS: A total of 154 abstracts were identified, of which 18 potentially relevant articles were selected; a final total of nine papers were included for analysis. Comparison of the findings of the selected studies was made difficult by the heterogeneity of the articles, all of them animal research papers that showed heterogeneity in the methodologies used and a high or moderate risk of bias. CONCLUSIONS: The topical application of bisphosphonate solution would appear to favor new bone formation in alveolar defects, and boosts the regenerative capacities of biomaterials resulting in increased bone density.

Evaluation of four designs of short implants placed in atrophic areas with reduced bone height: a three-year, retrospective, clinical and radiographic study.

The aim of the present study was to evaluate retrospectively the clinical and radiographic behaviour of four commercially-available short implants with different macrodesigns and microdesigns in areas in which the height of the bone was reduced. We took into account the success and survival, peri-implant crestal bone loss, and the level of probing at which the gum bled. Patients were included if they had been given one or more short implants (≤8.5mm long) in the posterior jaws at least three years earlier. Three hundred and ninety-one short implants were placed in 170 subjects, and were divided in four groups based on the brand of implant. The implants were evaluated one, two, and three years after they had been inserted. Short implants had a three-year survival and success rate of 90% in all groups, and bone loss was acceptable after three years with no significant differences between them. These results support the use of short implants as an effective and safe treatment. However, within the limitations of this study, the design of the implant does seem to influence the behaviour of peri-implant bone at the crestal level.

Osteogenic potential of platelet-rich plasma in dental stem-cell cultures.

The purpose of this study was to analyse the potential of platelet-rich plasma (PRP) culture media to induce osteogenic differentiation of periodontal ligament stem cells and dental pulp stem cells compared with four other methods of culture. Both types of cell were collected from 35 healthy patients and cultured in five different media (Dulbecco's modified eagle's medium (DMEM); DMEM and melatonin; DMEM and PRP; DMEM and ascorbic acid 200µmol; DMEM and l-ascorbate 2-phosphate 50µmol). Cells were characterised by flow cytometry. Alizarin Red stain, alkaline phosphatase stain, and the expression of collagen type 1 (Col-1), runt-related transcription factor (RUNX2), osteoprotegerin, and osteopontin (quantified by qRT-PCR) were used to detect the osteogenic profile in each culture. Flow cytometry showed that both types of stem cell were a homogeneous mixture of CD90(+), CD105(+), STRO-1(+), CD34 (-), and CD45 (-) cells. Dental pulp stem cells that were cultured with PRP showed the best osteogenic profile (RUNX2 p=0.0002; osteoprotegerin p=0.001). The group of these stem cells that showed the best osteogenic profile was also cultured with PRP (osteoprotegerin p=0.001). Medium five (with l-ascorbate 2-phosphate 50µmol added) showed an increase in all osteogenic markers for periodontal ligament stem cells after PRP, while the best culture conditions for osteogenic expression of dental pulp stem cells after PRP was in medium four (ascorbic acid 200µmol added). These results suggested that culture in PRP induces osteogenic differentiation of both types of stem cell, modulating molecular pathways to promote bony formation.

Osseoinductive elements for promoting osseointegration around immediate implants: a pilot study in the foxhound dog.

OBJECTIVE: The aim of this study was to evaluate the effects of topical applications of melatonin over implant surfaces placed immediately after extraction by means of histological and histomorphometric analysis of peri-implant tissues. MATERIAL AND METHODS: Six American foxhound dogs were used in the study; mandibular premolar distal roots were extracted. Thirty-six immediate conical implants were randomly assigned to the distal site on each site of the mandible in three groups: (Group CI) 12 titanium implants alone; (Group MI) 12 titanium implants supplemented with melatonin; and (Group DI) 12 titanium implants supplemented with vitamin D (DI). Prior to implanting test, implants (MI) were submerged in melatonin 5% solution, and implants from (DI) group were submerged in vitamin D 10% solution. No treatment was applied at control implants. After 12 weeks, animals were sacrificed. Block sections were obtained and processed for mineralized ground sectioning. Bone-to-implant contact (total BIC), new bone formation (NBF), inter-thread bone (ITB) and histological linear measurements (HLM) were analyzed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. Total BIC values were 48.36 ± 7.45* for the MI group and 44.82 ± 10.98 for the CI group (P = 0.035) with statistically significant difference between groups. BIC% were 41.36 ± 3.93 for MI and 41.34 ± 9.26 for CI (P > 0.05). Inter-thread bone formation values were MI 15.99 ± 2.43* and CI 14.79 ± 3.62 (P = 0.03), MI showing significantly better results. No statistically significant differences in peri-implant new bone formation could be found between the two groups: MI 25.37 ± 2.32, CI 26.55 ± 7.75 (P > 0.05). Linear measurements showed that the MI group showed significantly less lingual crestal bone loss (CBL) (MI 0.52 ± 0.74*, CI 0.92 ± 1.98) (P = 0.045) and less lingual peri-implant mucosa (PIM) (MI 3.13 ± 1.41*, CI 3.71 ± 1.81) (P = 0.042). No significant differences were observed in the buccal aspect. CONCLUSIONS: Within the limitations of this animal study, the topical application of melatonin improved bone formation around immediate implants and reduced lingual bone and lingual peri-implant mucosa, after 12 weeks of osseointegration.

Temperature and time variations during osteotomies performed with different piezosurgical devices: an in vitro study.

AIM: The aim of this experimental in vitro study was to evaluate the effects of the piezoelectric device in temperature and time variations in standardized osteotomies performed with similar tip inserts in bovine bone blocks. METHODS: Two different piezosurgical devices were used the OE-F15(®) (Osada Inc., Los Angeles, California, USA) and the Surgybone(®) (Silfradent Inc., Sofia, Forli Cesena, Italy). Serrated inserts with similar geometry were coupled with each device (ST94 insert/test A and P0700 insert/test B). Osteotomies 10 mm long and 3 mm deep were performed in bone blocks resembling type II (dense) and type IV (soft) bone densities with and without irrigation. Thermal changes and time variations were recorded. The effects of bone density, irrigation, and device on temperature changes and time necessary to accomplish the osteotomies were analyzed. RESULTS: Thermal analysis showed significant higher temperatures during piezosurgery osteotomies in hard bone without irrigation (P < 0.05). The type of piezosurgical device did not influence thermal variations (P > 0.05). Time analysis showed that the mean time values necessary to perform osteotomies were shorter in soft bone than in dense bone (P < 0.05). CONCLUSIONS: Within the limitations of this in vitro study, it may be concluded that the temperature increases more in piezosurgery osteotomies in dense bone without irrigation; the time to perform the osteotomy with piezosurgery is shorter in soft bone compared to hard bone; and the piezosurgical device have a minimal influence in the temperature and time variations when a similar tip design is used during piezosurgery osteotomies.

Bisphosphonate-associated osteonecrosis of the jaw 2 years after teeth extractions: a case report solved with non-invasive treatment.

Bisphosphonates are a type of drugs known to inhibit bone resorption through complex interventions. Their primary mechanism of action is aimed at the cellular level, inhibiting osteoclast activity and, thus, bone resorption. Bisphosphonates are, therefore, very widely used, with many patients receiving continuous treatment for years. But it is well known that these drugs can produce osteonecrosis of the jaw and this is their principal risk. A 75-year-old woman received dental treatment before starting intravenous BP therapy for a breast cancer. She started intravenous bisphosphonate treatment with monthly protocol and after two years the patient presented a wound compatible with osteonecrosis of the jaw.

Histomorphometric and mineral degradation study of Ossceram: a novel biphasic B-tricalcium phosphate, in critical size defects in rabbits.

OBJECTIVE: To carry out a histomorphometric analysis of a new highly porous (95%) biphasic calcium phosphate (hydroxyapatite 60%/B-tricalcium phosphate 40%), used to fill critical size defects in rabbit tibiae, supplementing histomorphometric findings with radiographic thermal imaging, EDX analysis and Ca/P ratio mapping at different time stages. MATERIALS AND METHODS: Two critical size defects of 6 mm diameter were created in both tibiae of 21 New Zealand rabbits, test group (Ossceram) and control group. Histomorphometric, radiographic thermal imaging, EDX and element mapping analysis were performed at 15, 30 and 60 days after graft insertion. RESULTS: Histomorphometric analysis at 30 days showed more new bone formation in defects filled with Ossceram 4.41 ± 0.23 mm than the test group 1.94 ± 0. 28 mm (P<0.05). Element analysis revealed higher percentages of Ca (42.33 ± 2.8%) and P (1.3 ± 0.8%) in the test group than in the control group (P<0.05). Element mapping showed that Ca and P were concentrated in medullar and cortical zones in the test group but were concentrated only in cortical zones in the control group. Test group histomorphometry at 60 days showed complete closure of the cortical defect 5.37 ± 0.32 mm more than the control group 2.3 ± 0.54 mm. There was no cortical defect closure or medullar bone formation in the control group (P<0.05). Element analysis revealed higher percentages of Ca (32.26 ± 21.7%) and P (1.5 ± 0.3%) in the test group than in the control group (P<0.05). CONCLUSION: Defects of a critical size in a rabbit tibia model can be sealed using a highly porous biphasic calcium phosphate; this supports new bone formation, creates a bridge between borders and facilitates bone ingrowth. Furthermore, this study observed partial dissolution of the mineral phase of the graft material and its incorporation into the surrounding bone. Radiographic thermal imaging may be used to supplement histological and chemical analyses.

Bone remodelling after regenerative procedures around implants placed in fresh extraction sockets: an experimental study in Beagle dogs.

INTRODUCTION: After a tooth extraction, the height of the buccal wall tends to decrease. The literature indicates that regenerative techniques (guided bone regenerative [GBR] techniques) have succeeded in improving the bone levels. Therefore, this experiment set out to compare the physiological bone remodelling in Beagle dog models after implant placement in a fresh extraction socket, with and without the application of regenerative procedure. MATERIALS AND METHODS: Five dogs were used in this study. Test and control sites were randomly selected. The experimental teeth (fourth pre-molar and first molar) were hemi-sected removing the distal roots and placing implants. Porcine bone was placed to fill the gap around the implant on the test sites and a reabsorbable membrane was used to cover the area. The dogs were put down at different times (2 weeks, 1 month and 3 months). The measurements were taken immediately and at 2, 4, 12 weeks after implant placement. Student's test for paired data was used to compare the means of the clinical measurements. RESULTS: At 2 weeks: On the control sites, few signs of resorption were detected at the first molar only, while at the test sites bone levels were placed at the implant shoulder or above. At 4 weeks: On the control site, slight bone remodelling was observed, while on the test site minor signs of resorption or an increase of bone levels were detected. At 12 weeks: The alveolar crest on the control sites showed various degrees of remodelling. On the test sites stable bone levels or an increase of bone crest was observed. CONCLUSION: With the limits of this study, the findings showed that GBR techniques were able to limit resorption of the alveolar crest after tooth extraction. A pattern of bone remodelling after tooth extraction and implant placement was observed in the control sites (no GBR) as well as in test sites (GBR), and although the exact cause of this is unclear, surgical trauma could play a role. Further studies are necessary to confirm these results and to clarify the precise causes of bone remodelling in fresh extraction sockets.

Immediate post-extraction implants subject to immediate loading: a meta-analytic study.

UNLABELLED: Since Brånemark first started developing its implant system, there has been a continuous and significant evolution in oral implantology through experimental and clinical research, and many of the concepts that were once considered valid have now become the subject of debate. The insertion of the implant immediately after extraction of the tooth to be substituted has now become the implant treatment of choice and is associated with preserving the bone structure and the gingival architecture, as well as with reducing the treatment time, which ultimately benefits the patient. OBJECTIVE: To evaluate the success rate of the immediate post-extraction implants (IPI) subject to immediate loading. STUDY DESIGN: A meta-analytic study was carried out on 659 immediate post-extraction implants obtained from a bibliographic review of 25 articles published within the last 9 years. RESULTS: We obtained a sample of 322 patients who had been treated with a total of 659 implants placed immediately following extraction. The mean age of the patients was 51 years old. A total of 441 implants were inserted in the maxilla, 152 in the mandible and 64 were placed in an unspecified location. The survival rate ranged between 85% and 100%. CONCLUSIONS: Immediate post-extraction implant treatment is an implant alternative with a survival rate similar to that of the conventional technique for implant placement and enables preserving both the bone structure and gingival architecture, as well as providing immediate functional loading, thus improving the quality of the treatment as far as the patient is concerned.

Femtosecond laser microstructuring of zirconia dental implants.

This study evaluated the suitability of femtosecond laser for microtexturizing cylindrical zirconia dental implants surface. Sixty-six cylindrical zirconia implants were used and divided into three groups: Control group (with no laser modification), Group A (microgropored texture), and Group B (microgrooved texture). Scanning electron microscopy observation of microgeometries revealed minimal collateral damage of the original surface surrounding the treated areas. Optical interferometric profilometry showed that ultrafast laser ablation increased surface roughness (R(a), R(q), R(z), and R(t)) significantly for both textured patterns from 1.2 x to 6 x-fold when compared with the control group (p < 0.005). With regard to chemical composition, microanalysis revealed a significant decrease of the relative content of contaminants like carbon (Control 19.7% ± 0.8% > Group B 8.4% ± 0.42% > Group A 1.6% ± 0.35%) and aluminum (Control 4.3% ± 0.9% > Group B 2.3% ± 0.3% > Group A 1.16% ± 0.2%) in the laser-treated surfaces (p < 0.005). X-ray diffraction and Raman spectra analysis were carried out to investigate any change in the crystalline structure induced by laser processing. The original predominant tetragonal phase of zirconia was preserved, whereas the traces of monoclinic phase present in the treated surfaces were reduced (Control 4.32% > Group A 1.94% > Group B 1.72%) as the surfaces were processed with ultrashort laser pulses. We concluded that femtosecond laser microstructuring offers an interesting alternative to conventional surface treatments of zirconia implants as a result of its precision and minimal damage of the surrounding areas.

Histological and histomorphometric evaluation of immediate implant placement on a dog model with a new implant surface treatment.

PURPOSE: The aim of this study was to evaluate crestal bone resorption and bone apposition resulting from immediate post-extraction implants in the canine mandible, comparing a conditioned sandblasted acid-etched implant surface with a non-conditioned standard sandblasted implant surface. MATERIAL AND METHODS: In this experimental study, third and fourth premolars and distal roots of first molars were extracted bilaterally from six Beagle dog mandibles. Each side of the mandible received three assigned dental implants, with the conditioned surface (CS) on the right side and the non-conditioned surface (NCS) on the left. The dogs were sacrificed at 2 (n=2), 4 (n=2) and 12 weeks (n=2) after implant placement. RESULTS: The microscopic healing patterns at 2, 4 and 12 weeks for both implant types (CS and NCS) yielded similar qualitative bone findings. The mean crestal bone resorption was found to be greater for all implants with NCS (2.28+/-1.9 mm) than CS (1.21+/-1.05 mm) at 12 weeks. The mean percentage of newly formed bone in contact with implants was greater in implants CS (44.67+/-0.19%) than with the NCS (36,6+/-0.11%). There was less bone resorption with the CS than the NCS. CONCLUSION: The data show significantly more bone apposition (8% more) and less crestal bone resorption (1.07 mm) with the CS than with the NCS after 12 weeks of healing. This CS can reduce the healing period and increase bone apposition in immediate implant placements.