Survival of Dyna Implants: A Retrospective Study with 1 to 6 Years of Follow up.

Objectives: Dental implants are a prominent scientific breakthrough and are frequently applied for replacement of the missing teeth. From the clinicians' point of view, long-term studies are essential to find out the predictability of dental implant systems. Materials and Methods: In this retrospective study, 1,626 patients who received 4,389 Dyna implants in a private office between 2013-2019 were evaluated. All statistical analyses were performed using SPSS 25 for Windows. P values less than 0.1 were considered significant for regression analysis. Results: Dyna implant ts (4389) placed from 2013 to 2019 were evaluated in this study. One-hundred and thirty-three (3.03%) implants failed during the healing period or recall visits. Eighty-nine implants (2.03%) failed immediately and 44 (1%) failed after 3 months. Conclusion: The present study showed that the Dyna dental implant system had high implant survival, and it had all the survival criteria similar to world-class dental implant systems.

Photo-sonodynamic antimicrobial chemotherapy via chitosan nanoparticles-indocyanine green against polymicrobial periopathogenic biofilms: Ex vivo study on dental implants.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a treatment to deal with microorganisms, which is limited to treating microbial biofilms due to poor light penetration. Sonodynamic antimicrobial chemotherapy (SACT) can be used for circumventing the limitations of aPDT to inhibit the polymicrobial biofilms. The objective of this study has been focused on the simultaneous use of aPDT and SACT, which is called photo-sonodynamic antimicrobial chemotherapy (P-SACT) to inhibit the biofilms of periopathogens bacteria on surfaces of the titanium dental implants. MATERIALS AND METHODS: Following synthesis and confirmation of Chitosan Nanoparticles-Indocyanine green (CNPs-ICG) as photo-sonosensitizer, the mature biofilm model of the polymicrobial synergism of periopathogens was formed on the surface of the titanium dental implants. The quantitative and qualitative evaluations of periopathogens biofilms were performed using microbial viability and scanning electron microscopy analysis of the following groups of treatment modalities (n = 5): 1- Control (periopathogens biofilm without treatment), 2- ICG, 3- CNPs-ICG, 4- diode laser, 5- aPDT/ICG, 6- aPDT/CNPs-ICG, 7- ultrasound, 8- SACT/ICG, 9- SACT/CNPs-ICG, 10- PSACT/ICG, 11- PSACT/CNPs-ICG, and 12-0.2% chlorhexidine (CHX). RESULTS: A significant reduction in the log10 CFU/mL of periopathogens was observed in the groups treated with aPDT/ICG, aPDT/CNPs-ICG, SACT/ICG, SACT/CNPs-ICG, PSACT/ICG, PSACT/CNPs-ICG, and 0.2% CHX up to 5.3, 6.5, 5.6, 6.6, and 8.8 log, respectively, when compared with control group (P < 0.05). PSACT/CNPs-ICG group demonstrated significantly higher capacity in eliminating the periopathogens biofilm compared with other groups (P < 0.05). However, there was no significant difference between PSACT/CNPs-ICG and 0.2% CHX (P > 0.05). Microscopic images revealed that biofilms treated with PSACT were comprised mainly of deformed and dead cells. CONCLUSIONS: These results highlight the potential of PSACT/CNPs-ICG for the decontamination of the dental implant surfaces from the polymicrobial synergism of periopathogens biofilm.

Photobiomodulation Therapy for the Management of Patients With Inferior Alveolar Neurosensory Disturbance Associated With Oral Surgical Procedures: An Interventional Case Series Study.

Introduction: Inferior alveolar nerve (IAN) injury is a serious complication during intraoral surgeries. We aimed to evaluate the outcome of photobiomodulation (PBM) therapy in patients with IAN injury associated with third molar or implant procedures. Methods: Eight patients with an alteration of sensory function of the IAN after third molar or implant surgeries were enrolled in this case series study. The patients received 10 sessions of PBM therapy (810 nm diode laser, 200 mW, 10 J/cm2 per point, three times a week). Pinprick (PP) and visual analogue scale (VAS) neurosensory tests were recorded at each treatment session and 14 days after the last treatment. The association between explanatory variables and the outcome of interest was analyzed using generalized estimating equations. Results: The median percentage change of outcomes from the first to the last visit was as follows: VAS score: +125.00% (range: 50.00 to 166.67); PP score: +350% (range: 150 to 800). The duration of paresthesia was inversely correlated with changes in VAS and PP scores. No significant association was found between patients' gender or age and changes in VAS and PP scores. Conclusion: Considering the limitations of this study, PBM with the parameters used in this study presented positive effects on neurosensory recovery in patients suffering from IAN injury associated with routine intraoral procedures. Patients with shorter duration of paresthesia tended to respond more favorably to PBM therapy.

Effect of Antimicrobial Photodynamic Therapy Using Indocyanine Green Doped with Chitosan Nanoparticles on Biofilm Formation-Related Gene Expression of Aggregatibacter actinomycetemcomitans.

OBJECTIVES: Eradication of Aggregatibacter actinomycetemcomitans (A. actionmycetemcomitans), as an opportunistic periodontopathogen, and inhibition of its virulence factor expression require a new adjunctive therapeutic method. In this study, we accessed the expression level of rcpA gene, as a virulence factor associated with A. actinomycetemcomitans biofilm formation, following treatment by antimicrobial photodynamic therapy (aPDT) using indocyanine green (ICG) doped with chitosan nanoparticles (CS-NPs@ICG). MATERIALS AND METHODS: CS-NPs@ICG was synthesized and examined using scanning electron microscopy (SEM). A. actinomycetemcomitans ATCC 33384 strain was treated with CS-NPs@ICG, as a photosensitizer, which was excited with a diode laser at the wavelength of 810 nm with the energy density of 31.2 J/cm2. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the changes in rcpA gene expression level. RESULTS: Synthetized CS-NPs@ICG was confirmed via SEM. The results revealed that CS-NPs@ICG-mediated aPDT could significantly decrease rcpA gene expression to 13.2-fold (P<0.05). There was a remarkable difference between aPDT using CS-NPs@ICG and ICG (P<0.05). The diode laser, ICG, and CS-NPs@ICG were unable to significantly downregulate rcpA gene expression (P>0.05). CONCLUSION: aPDT with CS-NPs@ICG leads to a decrease of the virulence factor of A. actinomycetemcomitans and can be used as an adjunct to routine treatments for successful periodontal therapy in vivo.

Comparing short dental implant and standard dental implant in terms of marginal bone level changes: A systematic review and meta-analysis of randomized controlled trials.

PURPOSE: To compare short implants (SH; 4-8 mm) to standard implants (ST; longer than 8 mm) in edentulous jaws, evaluating pri-implant marginal bone levels (MBLs) changes, implant failures (IFs), complications, and prosthesis failures (PFs). MATERIALS AND METHODS: Electronic searches were conducted through the PubMed, Web of Science, EMBASE, Scopus, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov to locate all randomized controlled trials (RCTs) comparing SH to ST. Meta-analysis procedures were performed on the weighted mean difference (WMD) and standardized mean difference (SMD) of MBLs using Stata. RESULTS: Twenty-three articles were included in this review. The WMD of MBLs when comparing SH to ST in both jaws up to 1-year follow-up was statistically significant preferring SH (WMD: -0.09 [CI: -0.12, -0.06], I2 : 67.0%). The efficacy of SH vs ST on SMD of MBLs was moderate (SMD: -0.43 [CI: -0.57, -0.28], I2 : 55.7%). There were no significant differences in IF (RR: 0.75 [0.44,1.27]) and PF (RR: 0.58 (0.22,1.581), and significantly higher biological complications (RR: 0.25 [0.15, 0.40]) for SH was observed compared to the ST in both jaws up to 1-year follow-up. CONCLUSIONS: SH and ST implants showed the comparable outcomes except biological complication preferring SH. Future systematic review and meta-analysis with longer and larger RCTs are required to confirm the present outcomes.

Transplantation of Bone Marrow-Derived Mesenchymal Stem Cells, Platelet-Rich Plasma, and Fibrin Glue for Periodontal Regeneration.

Appropriate regeneration of periodontal tissues is the primary purpose of periodontal disease treatment. The present study assessed the impact of three key regenerative elements-platelet-rich plasma (PRP), canine bone marrow mesenchymal stem cells (cBM-MSCs), and fibrin glue-on periodontal regeneration. In each of the study's five dogs, Class II furcation defects were established on the buccal surface of five teeth. One tooth (five total) from each dog was placed into one of five groups: (1) PRP + fibrin glue, (2) PRP + fibrin glue + cBM-MSCs, (3) fibrin glue, (4) cBM-MSCs + fibrin glue, and (5) control (no treatment). Histologic and histometric evaluations were performed to assess the formation of new bone, cementum, and the periodontal ligament. Different types of new bone and cementum, the maximum thickness of new cementum and the periodontal ligament (PDL), the vitality of bone, and the presence of inflammation or foreign-body reactions were also elucidated. The histologic and histometric evaluations revealed substantial differences in all groups between the observed maximum thickness of newly formed cementum and PDL. The percentage of bone and cement formation drastically increased with the combined presence of stem cells, fibrin glue, and PRP. The results showed that the inherent regenerative capacity of periodontal tissues can be sufficient if their latent self-repair mechanisms are stimulated.

Comparing 4-mm dental implants to longer implants placed in augmented bones in the atrophic posterior mandibles: One-year results of a randomized controlled trial.

BACKGROUND: Short implants have been proposed as an alternative for the rehabilitation of atrophic edentulous areas. PURPOSE: To evaluate the efficacy of 4-mm implants vs longer implants in the atrophic posterior mandibles. MATERIALS AND METHODS: Eleven patients with bilateral atrophic mandibles were rehabilitated with two to four 4-mm implants and 10 or 8-mm long implants in augmented bone using Guided Bone Regeneration procedure. One side of the mandibles was randomly allocated to vertical augmentation with mixed autogenous bone and allograft. Implants were placed in both sides of the mandible after 6 months, and loaded after another 2 months. Subsequently, implant and prosthesis failures, marginal bone levels changes, and any complication were evaluated after 1-year follow-up. RESULTS: In this study, one patient dropped out and no failures occurred. However, 4-mm implants loss of 0.30 ± 0.34 mm peri-implant marginal bone and long implants loss of 0.47 ± 0.54 mm marginal bone were observed after 1-year of follow-up. The difference between the two groups was not statistically significant (difference = -0.16 ± 0.68 mm; P = 0.46). Eight complications occurred in five augmented sites of the patients, and no complication was found to occur in the short implants sites. CONCLUSIONS: One-year after loading, 4-mm implants had similar outcomes as long implants in augmented bone. Therefore, short implants might be a feasible treatment in atrophic mandibles.

Histomorphometric Analysis of Bone Density in Relation to Tactile Sense of the Surgeon During Dental Implant Placement.

INTRODUCTION: A correct diagnosis and optimal treatment planning is essential for success in implant dentistry. Proper diagnosis of bone quality is an important part of the diagnostic procedure. OBJECTIVE: The purpose of this study was to correlate the tactile sense of the surgeon in the assessment of bone density to the histomorphometric analysis of bone quality. METHODS: In this study, 56 bone samples from 33 patients were harvested from implant sites with trephine drills. The samples were analyzed with Image J software. In the samples following parameters were measured: BV/TV, superficial cortical plate thickness, the number and thickness of haversian canals in cortical bone and the number, thickness and distance of trabecules in cancellous bone. The clinical hardness of bone during drilling was evaluated by surgeon according to Misch. GEE analysis with exchangeable correlation structure and linear model was used to evaluate the relationship between the tactile sense of the surgeon and histomorphometric parameters and all analysis was adjusted for two confounding variables: gender and location. RESULTS: There were 51.79% implants in D2 samples and 48.21% in D3. Bone classification according to Misch was significantly correlated to distance of trabecules in cancellous bone (P-value=0.05), and shown marginally significant correlation with mean superficial cortical bone thickness (P-value =0.07) and number of haversian canals (P-value =0.005) in cortical bone. DISCUSSION: There were differences between our results and others. The authors believed that these differences mainly are because of confounding factors, that in this study were eliminated. The clinical finding during surgery can approximately explain the histologic properties of bone. CONCLUSION: It is concluded that tactile sense of the surgeon can exhibit the histologic properties of the bone, and we are able to estimate the healing prognosis of the bone in implant placement.

Comparing Short Dental Implants to Standard Dental Implants: Protocol for a Systematic Review.

BACKGROUND: Short dental implants have been proposed as a simpler, cheaper, and faster alternative for the rehabilitation of atrophic edentulous areas to avoid the disadvantages of surgical techniques for increasing bone volume. OBJECTIVE: This review will compare short implants (4 to 8 mm) to standard implants (larger than 8 mm) in edentulous jaws, evaluating on the basis of marginal bone loss (MBL), survival rate, complications, and prosthesis failure. METHODS: We will electronically search for randomized controlled trials comparing short dental implants to standard dental implants in the following databases: PubMed, Web of Science, EMBASE, Scopus, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov with English language restrictions. We will manually search the reference lists of relevant reviews and the included articles in this review. The following journals will also be searched: European Journal of Oral Implantology, Clinical Oral Implants Research, and Clinical Implant Dentistry and Related Research. Two reviewers will independently perform the study selection, data extraction and quality assessment (using the Cochrane Collaboration tool) of included studies. All meta-analysis procedures including appropriate effect size combination, sub-group analysis, meta-regression, assessing publication or reporting bias will be performed using Stata (Statacorp, TEXAS) version 12.1. RESULTS: Short implant effectiveness will be assessed using the mean difference of MBL in terms of weighted mean difference (WMD) and standardized mean difference (SMD) using Cohen's method. The combined effect size measures in addition to the related 95% confidence intervals will be estimated by a fixed effect model. The heterogeneity of the related effect size will be assessed using a Q Cochrane test and I2 measure. The MBL will be presented by a standardized mean difference with a 95% confidence interval. The survival rate of implants, prostheses failures, and complications will be reported using a risk ratio at 95% confidence interval (P<.05). CONCLUSIONS: The present protocol illustrates an appropriate method to perform the systematic review and ensures transparency for the completed review. The results will be published in a peer-reviewed journal and social networks. In addition, an ethics approval is not considered necessary. TRIAL REGISTRATION: PROSPERO registration number: CRD42016048363; https://www.crd.york.ac.uk/PROSPERO/ display_record.asp?ID=CRD42016048363 (Archived by WebCite at http://www.webcitation.org/6wZ7Fntry).

Accuracy of Linear Measurements Using Cone Beam Computed Tomography in Comparison with Clinical Measurements.

OBJECTIVES: This study sought to evaluate the accuracy and errors of linear measurements of mesiodistal dimensions of Kennedy Class III edentulous space using cone beam computed tomography (CBCT) in comparison with clinical measurements. MATERIALS AND METHODS: Nineteen Kennedy Class III dental arches were evaluated. An impression was made of each dental arch and poured with dental stone. The distance was measured on dental cast using a digital Vernier caliper with an accuracy of 0.1mm and on CBCT scans. Finally, the linear mesiodistal measurements were compared and the accuracy of CBCT technique was evaluated by calculating absolute value of errors, intra-class correlation coefficient and simple linear regression model. RESULTS: In comparison with the cast method, estimation of size on CBCT scans had an error of -8.46% (underestimation) to 5.21% (overestimation). In 26.5% of the cases, an accepted error of ±1% was found. The absolute value of errors was found to be in the range of 0.21-8.46mm with an average value of 2.86 ±2.30mm. CONCLUSIONS: Although the measurements revealed statistically significant differences, this does not indicate a lower accuracy for the CBCT technique. In fact, CBCT can provide some information as a paraclinical tool and the clinician can combine these data with clinical data and achieve greater accuracy. Undoubtedly, calibration of data collected by clinical and paraclinical techniques and the clinician's expertise in use of CBCT software programs can increase the accuracy of implant placement.

Comparison of Bone Loss around Bone Platform Shift and Non-Bone Platform Shift Implants After 12 Months.

OBJECTIVES: The aim of the present randomized clinical trial was to evaluate marginal bone loss around two types of implants modified at the neck area: Nobel Active and Nobel Replace Groovy, both manufactured by Nobel Biocare. MATERIALS AND METHODS: A total of 25 Nobel Active and 21 Nobel Replace Groovy implants were included in the present study. The implants were placed based on the relevant protocol and patient inclusion and exclusion criteria. The amount of bone loss around implants was compared at 6 and 12-month intervals using digital periapical radiographs. RESULTS: The mean bone loss values in the Nobel Active and Nobel Replace Groovy groups were 0.682 mm and 0.645 mm, respectively, with no statistically significant difference based on the results of independent t-test (P=0.802). CONCLUSION: Use of both implant types yielded favorable results, with high durability. The two implant types exhibited no superiority over each other in terms of bone loss.

Comparison of Implant Stability Using Resonance Frequency Analysis: Osteotome Versus Conventional Drilling.

OBJECTIVES: Implant primary stability is one of the important factors in achieving implant success. The osteotome technique may improve primary stability in patients with poor bone quality. The aim of this study was to compare implant stability using two different techniques namely osteotome versus conventional drilling in the posterior maxilla. MATERIALS AND METHODS: In this controlled randomized clinical trial, 54 dental implants were placed in 32 patients; 29 implants were placed in the osteotome group and 25 in the conventional drilling group. Implant stability was assessed at four time intervals namely at baseline, one, two and three months after implant placement using resonance frequency analysis (RFA). RESULTS: Primary stability based on implant stability quotient (ISQ) units was 71.4±7 for the osteotome group and 67.4±10 for the control group. There was no statistically significant difference between the two groups in implant stability at any of the measurement times. In each group, changes in implant stability from baseline to one month and also from two months to three months post-operatively were not significant but from one month to two months after implant placement, implant stability showed a significant increase in both groups. CONCLUSION: The results of this study revealed that in both techniques, good implant stability was achieved and osteotome technique did not have any advantage compared to conventional drilling in this regard.

Regenerative Effects of Three Types of Allografts on Rabbit Calvarium: An Animal Study.

OBJECTIVES: The aim of this study was to histologically compare the regenerative properties of two allografts manufactured by two Iranian companies. MATERIALS AND METHODS: In this study, four 8-mm defects were produced in the calvaria of 12 rabbits. In three defects, three types of allografts namely ITB, CenoBone and Grafton were placed and one defect served as control. Samples were prepared and histomorphometric evaluations were carried out after healing periods of four weeks (interval 1) and eight weeks (interval 2). Qualitative and quantities variables were compared and analyzed with SPSS software. RESULTS: Mild inflammation was observed in 45% and 12.5% of the samples in the first and second intervals, respectively. Foreign body reaction was observed in only 5% of the samples. The quality of regenerated bone was immature, mixed and lamellar in 54.5%, 15.9% and 4.5% of the samples, respectively. The rate of allograft resorption was the highest and lowest in the CenoBone and Grafton samples, respectively. The mean amount of regenerated bone was higher in areas containing Grafton; however, the differences were not statistically significant. CONCLUSION: Despite the differences in the numerical values of bone regeneration, there were no statistically significant differences in bone generation among the material groups, and allografts manufactured in Iran can be suitable alternatives to Grafton with the same good properties. Further studies are necessary to clarify the efficacy of these allografts.

Frequency of Dental Implants Placed in the Esthetic Zone in Dental Clinic of Tehran University: A Descriptive Study.

OBJECTIVES: Anterior maxilla, known as the esthetic zone, plays an important role in facial and smile esthetics. This study assessed the frequency of implant treatments in the esthetic zone of patients presenting to Dental Implant Department of Tehran University during 2002-2012. MATERIALS AND METHODS: This descriptive study was conducted on dental records of patients receiving implant treatment during 2002-2012. Patient records were retrieved from the archives and patient demographics, implant characteristics, failure rate, prevalence of complications and implant systems were collected. The data were reported as frequency and percentage. RESULTS: Of a total of 2,381 implants placed in the mentioned time period, 492 (20.8%) had been placed in the anterior maxilla and 531 (22.3%) had been placed in the anterior mandible from canine to canine. Timing of implant placement was immediate in 12.0%, early in 0.5% and late in 87.4%. Survival rate was 99.1%. Rate of failure was 0.8%. Failure rate was 0.4% in the maxillary and 1.1% in the mandibular canine to canine region. Complications were reported in 10.1% of patients. Rate of complications was 18.3% in the maxillary canine to canine, 8.9% in the mandibular canine to canine, 18.1% in the maxillary first premolar to first premolar and 9.5% in the mandibular first premolar to first premolar. The frequency of bone grafts placed in these areas was 17.6%, 33.9%, 13.6%, 32.1% and 14.3%, respectively. CONCLUSION: Of implants placed in our center, around 20% were in the anterior maxilla, and delayed implant placement was the most commonly adopted technique.

Isolation and Assessment of Mesenchymal Stem Cells Derived From Bone Marrow: Histologic and Histomorphometric Study in a Canine Periodontal Defect.

The aim of the present study was to investigate an isolation procedure to culture mesenchymal stem cells derived from bone marrow and evaluate their potential in periodontal regeneration. Potential stem cells from bone marrow, aspirated from the iliac crest of nine mongrel canines 1 to 2 years of age, were cultivated. After the examination of surface epitopes of the isolated cells, the total RNA from osteogenic, adipogenic, and chondrogenic cell cultures were analyzed by reverse transcription polymerase chain reaction (RT-PCR) to confirm stem cell gene expressions. 2 × 10(7) mL of the stem cells were loaded on 0.2 mL of anorganic bovine bone mineral (ABBM) granules. In each animal, bilateral acute/chronic intrabony periodontal defects were created surgically and by placement of ligatures around the cervical aspect of the teeth. At week 5, after flap debridement, the bilateral defects were randomly assigned to 2 treatment groups: the control group received ABBM, and the test group received BMSCs-loaded ABBM. Eight weeks after transplantation, regenerative parameters were analyzed histologically and histometrically. The RNA expressions confirmed the cultivation of mesenchymal stem cell. More new cementum and periodontal ligament (PDL) were measured in the test group (cementum: 3.33 ± 0.94 vs 2.03 ± 1.30, P = 0.027; PDL: 2.69 ± 0.73 vs 1.53 ± 1.21, P = 0.026). New bone formation was similar in both groups (2.70 ± 0.86 vs 1.99 ± 1.31; P = 0.193). Mesenchymal stem cells derived from bone marrow should be considered a promising technique for use in patients with periodontal attachment loss and merits further investigations.

Effect of low-level laser therapy irradiation and Bio-Oss graft material on the osteogenesis process in rabbit calvarium defects: a double blind experimental study.

This study aims to assess the effect of low-level laser therapy (LLLT) irradiation and Bio-Oss graft material on the osteogenesis process in the rabbit calvarium defects. Twelve white male New Zealand rabbits were included in this study. Four 8-mm diameter identical defects were prepared on each rabbit's calvarium. One site was left as an untreated control (C), the second site was filled with Bio-Oss (B), the third site was treated with laser irradiation (L), and the fourth site treated with Bio-Oss and laser irradiation (B + L). In the laser group, a diode laser (wavelength 810 nm, output power 300 mW, irradiation mode CW, energy density 4 J/cm2) was applied immediately after surgery and then one other day for the next 20 days. After 4 and 8 weeks, the animals were sacrificed and histological and histomorphometric examinations were performed and the data were subjected to Friedman and repeated measurements ANOVA tests. Significant differences were not found regarding inflammation severity, foreign body reactions, and vitality of newly formed bone on 4th and 8th week after operation. The mean amount of new bone was 15.83 and 18.5% in the controls on the 4th and 8th week; 27.66 and 25.16% in the laser-irradiated group; 35.0 and 41.83% in Bio-Oss and 41.83 and 47.0% in the laser + Bio-Oss treated specimens with significant statistical differences (p <0.05). Application of LLLT in combination with Bio-Oss® can promote bone healing. Therefore, LLLT may be clinically beneficial in promoting bone formation in skeletal defects.

Effects of two types of anorganic bovine bone on bone regeneration: a histological and histomorphometric study of rabbit calvaria.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of two types of bone substitutes, Bio-Oss and NuOss, for repair of bone defects. MATERIALS AND METHODS: This study was performed on the calvaria of 14 New Zealand rabbits. The 6mm critical size defect (CSD) models of bone regeneration were used. Three CSDs were created in each surgical site. The first defect was filled with NuOss, the second one with Bio-Oss and the third one remained unfilled as the control. After healing periods of one and two months (seven animal for each time point), histological and histomorphometric analyses were carried out to assess the amount of new bone formation, presence of inflammation, foreign body reaction and type of new bone. Qualitative variables were analyzed by multiple comparisons, Wilcoxon, Friedman and Mann Whitney tests. Quantitative variables were analyzed using the Mann-Whitney and Wilcoxon tests. Level of statistical significance was set at 0.05. RESULTS: The level of inflammation was not significantly different at four and eight weeks in the Bio-Oss (P=0.944), NuOss (P=1.000) and control groups (P=0.71). At four weeks, foreign body reaction was not observed in Bio-Oss, NuOss and control groups. There was no significant difference in the type of the newly formed bone at four and eight weeks in any group (P=0.141 for Bio-Oss, P=0.06 for NuOss and P=0.389 for the control group). CONCLUSION: Deproteinized bovine bone mineral can be used as a scaffold in bone defects to induce bone regeneration.

Comparison of amnion allograft with connective tissue graft for root coverage procedures: a double-blind, randomized, controlled clinical trial.

OBJECTIVE: The aim of the present double-blind, randomized, controlled study was to evaluate and compare the efficacy of amnion allograft and connective tissue graft in covering denuded root surfaces. METHODS: Seventy-one teeth in 22 patients with gingival recession were treated randomly with coronally displaced flap plus connective tissue graft (control group, n = 29 recessions in 10 patients) or coronally displaced flap plus amnion allograft (test group, n = 42 recessions in 12 patients). The amount of root coverage and clinical parameters (probing depth, recession depth, clinical attachment level, recession width, gingival width, and papilla dimensions) were measured at baseline and at 3 and 6 months postoperatively. RESULTS: Average root coverage percentages after 6 months in the test and control groups were 67% (2.3 +/- 0.289 mm) and 54% (2.24 +/- 0.519 mm), respectively, with no statistically significant differences (p = 0.054). The changes in depth and width of recessions and in gingival width were significant 3 and 6 months after surgery compared to baseline (p = 0.000). Variations in the level of attachment and probing depths after 6 months were statistically significant in the test group compared to the control group (p = 0.002). Papilla dimensions were significantly correlated with root coverage (p = 0.00). CONCLUSIONS: Amnion allograft might be a suitable alternative to connective tissue graft in procedures to cover denuded root surfaces and can reduce recession depth.

Autologous dental pulp stem cells in regeneration of defect created in canine periodontal tissue.

This study aimed to investigate effects of dental pulp stem cells (DPSCs) on regeneration of a defect experimentally created in the periodontium of a canine model. Surgically created mesial 3-walled periodontal defects with ligature-induced periodontitis were produced bilaterally in the first lower premolar teeth of 10 mongrel dogs. Simultaneously, DPSCs were derived from the maxillary premolar teeth of the same dogs. Four weeks after creation of the periodontitis model, autologous passaged-3 DPSCs combined with Bio-Oss were implanted on one side as the test group. On the other side, only Bio-Oss was implanted as a control. Eight weeks after surgery, regeneration of the periodontal defects was evaluated histologically and histomorphometrically in terms of bone, periodontal ligament (PDL), and cement formation. Histologically, in all test specimens (10 defects), regeneration of cementum, bone, and PDL was observed. In the control groups, although we observed the regeneration of bone in all defects, the formation of cementum was seen in 9 defects and PDL was seen in 8 defects. Histomorphometric analyses showed that the amount of regenerated cementum and PDL in the test groups (3.83 ± 1.32 mm and 3.30 ± 1.12 mm, respectively) was significantly higher than that of the control groups (2.42 ± 1.40 mm and 1.77 ± 1.27 mm, respectively; P < .05). A biocomplex consisting of DPSCs and Bio-Oss would be promising in regeneration of periodontal tissues.

An unusual bone loss around implants.

Pre-implant disease is an inflammatory process that affects the surrounding tissues of a functional osseointegrated implant. It is usually the result of a disequilibrium between the micro-flora and the defense system. This case reports a 57-year-old man with unusual bone loss around dental implants. This was an unusual case of peri-implantitis that occurred only in the implants on one side of the mouth although they were all unloaded implants.