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1.

Background

Silver diamine fluoride (SDF) is used topically to prevent or arrest caries. The authors' aim was to characterize the kinetics of silver and fluoride after topical application of SDF.

Methods

Sixteen adults participated in a pharmacokinetics study after the application of 38% SDF to 5 teeth (approximately 50 microliters, estimated 4-11 milligrams per participant). Serum and urine samples were collected over 24 hours after application and were analyzed for silver and fluoride.

Results

Silver serum peak was 0.67 (standard deviation [SD], 0.49) nanograms per milliliter; median time to peak was 3 hours. The estimated elimination half-life of silver was 46 (SD, 26) hours. No silver was recovered in urine. Baseline fluoride serum levels ranged from less than 10 through 50 ng/mL (< 0.01-0.05 parts per million) and fluctuated around baseline after SDF. The 24-hour urinary fluoride was 1.29 (SD, 0.81) mg.

Conclusions

SDF was well tolerated in this study, and no adverse events related to SDF were reported.

Practical Implications

This clinical study confirmed that topical application of 38% SDF, in growing use in the United States, is safe and well tolerated in healthy adults.  相似文献   

2.

Statement of problem

Identifying factors that affect the clinical outcomes of implant therapy is important.

Purpose

The purpose of this retrospective study was to determine whether implant location was a factor affecting the complication and failure rates of single-tooth implant-supported restorations in a predoctoral setting.

Material and methods

The charts of 431 patients treated with a surgically placed dental implant and restored with a single crown in the predoctoral clinic were analyzed. Data on implant location, type of complication (surgical or prosthetic), and type of failure were collected and analyzed according to implant location using the Fisher Exact Test and Mantel-Haenszel Exact Chi Square Test analysis (α=.05).

Results

The charts revealed 158 complications (68 surgical and 90 prosthetic) in 110 patients, and 3.9% of the implants failed. No statistically significant difference was found between the number of surgical complications or prosthetic complications in the maxilla and the mandible (P=.469).

Conclusions

Jaw location (maxilla compared with mandible) of the implant had no statistically significant impact on the incidence of surgically or prosthetically related complications. No statistically significant difference was found in overall implant failures, surgical failures, and prosthetic failures between maxillary and mandibular implants.  相似文献   

3.

Introduction

In edentulous patients the form and size of the maxillary sinus vary greatly. Therefore sinus floor augmentation is a standard procedure for implantological purposes. As the sinus membrane cannot be characterized as periosteum, various augmentation materials are used.

Hypothesis

an artificially generated space underneath the sinus membrane in the floor of the sinus will lead to spontaneous callus forming and a stable bony consolidation without augmentation material.

Methods

Ten edentulous patients with highly atrophic maxillae were selected. Augmentation of the sinus floor was carried out in a split-mouth study design: On one side a combination of autogenous and xenogenous bone was used, and on the contralateral side a sinus membrane elevation was performed without using any substitutes. After a 6-month interval bone specimens from the test regions were harvested during implant placement.

Results

Clear histological evidence of new bone formation was found in all human bone specimens. An active de-novo bone formation process could be proven by the presence of Haversian systems (osteons) displaying osteoblastic and osteoclastic activity.

Conclusion

In the maxillary sinus of edentulous patients a spontaneous callus-derived de-novo bone formation is possible by elevating the sinus membrane without using augmentation materials.  相似文献   

4.

Purpose

This systematic review aimed at assessing the effects of PRGF in new bone formation, soft tissue healing and post-operative pain and swelling in sites that underwent ridge preservation, ridge augmentation and maxillary sinus augmentation procedures.

Materials and methods

A comprehensive literature search employing seven databases was conducted by two independent reviewers. Only randomized and non-randomized controlled clinical trials using PRGF alone or in combination with bone grafting materials were selected.

Results

Overall, 919 studies were identified, of which a total of 8 articles were included in the qualitative analysis. Two of the selected studies reported on ridge preservation, one on ridge augmentation and five on maxillary sinus augmentation. Positive results were recorded for soft tissue healing and post-operative pain and swelling following these procedures. However, outcomes of PRGF on new bone formation post extraction and on maxillary sinus augmentation when combined with other biomaterials were conflicting. Meta-analysis could not be conducted for any variables due to the heterogeneity of selected studies.

Conclusion

Limited evidence exists on the effects of PRGF in different intraoral bone grafting procedures, with some benefit reported on soft tissue healing and post-operative symptomatology. As this platelet concentrate is commonly used in clinical practice, further research is needed to fully assess its clinical indications and effectiveness.  相似文献   

5.

Background

The authors conducted a systematic review that addresses the following population, intervention, comparison, outcome question: “In adults requiring dental therapy with pulpally involved teeth, what is the comparative efficacy of buffered local anesthetics (LAs) compared with that of nonbuffered LAs in achieving anesthetic success?”

Types of Studies Reviewed

The authors searched MEDLINE, Scopus, Cochrane Library, ClinicalTrials.gov, World Health Organization International Trials Registry Platform, OpenGrey, Google Scholar Beta, and 2 textbooks to identify double-blinded randomized controlled trials in which researchers directly compared the efficacy of buffered and nonbuffered LAs in adult participants, as well as any associated side effects. Furthermore, they checked the reference lists of all included and excluded studies to identify any further trials. Weighted anesthesia success rates were estimated and compared by using a random-effects model.

Results

A total of 14,011 studies were initially identified from the search; 5 double-blinded randomized clinical trials met inclusion criteria. Buffered LAs were more likely to achieve successful anesthesia than nonbuffered LAs (odds ratio, 2.29; 95% confidence interval, 1.11 to 4.71; P = .0232; I2 = 66%).

Conclusions and Practical Implications

This investigation revealed that buffered LAs are more effective than nonbuffered LAs when used for mandibular or maxillary anesthesia in pulpally involved teeth. Buffering of LAs has 2.29 times greater likelihood of achieving successful anesthesia.  相似文献   

6.

Introduction

In the literature, several prevalence studies on root canal anatomy using cone-beam computed tomographic technology are currently available although their results remain disperse. This systematic review aimed to appraise and combine, under strict criteria conditions, selected prevalence studies in order to comprehend the distribution of root canal configuration types among different populations.

Methods

This systematic review was registered in PROSPERO. Six electronic databases were accessed, and the studies were selected according to a predefined inclusion/exclusion criteria. References of the collected studies and 3 peer-reviewed endodontic journals were hand searched. The authors of the selected studies were contacted for additional information. All eligible studies were submitted to a scientific merit evaluation by 2 evaluators independently, who also reached a final consensus for each study score using the Joanna Briggs Institute Critical Appraisal tool for prevalence studies.

Results

Fifty-two studies from 28 different countries including 102,610 teeth and presenting a Joanna Briggs Institute Critical Appraisal tool average score of 80.5% were included in this review. Overall, results showed a wide prevalence range of the second mesiobuccal canal in maxillary first and second molars but also a high prevalence of single-rooted configuration in maxillary first premolars and mandibular second molars and 3-rooted morphology in the mandibular first molar of Asian populations.

Conclusions

The included studies showed a global tendency for a particular morphology in some groups of teeth, whereas others showed diversity in specific anatomic types among different populations.  相似文献   

7.

Introduction

The purpose of this study was to predict the fracture resistance of an endodontically treated first maxillary molar with diverse access cavities using the extended finite element model (XFEM).

Methods

Based on micro–computed tomographic data of first maxillary molars, the model of a natural tooth and 3 endodontically treated teeth with conservative endodontic cavity, modified endodontic cavity, and traditional endodontic cavity were generated. Four static loads (800 N in total) were applied vertically to the contact points. The distributions of von Mises stress and maximum principal stress were calculated. XFEM was performed to simulate crack initiation and propagation in enamel and dentin.

Results

In the cervical region, larger stress concentration areas were found in the modified endodontics cavity and the traditional endodontic cavity compared with the natural tooth and the conservative endodontic cavity. Von Mises stress was concentrated around the palatal root, and tensile stress was concentrated on the mesiobuccal root. The XFEM results showed that the cracks in the enamel were initiated from the mesial groove, propagated to the central fossa, and finally initiated the damage in the dentin.

Conclusions

The fracture resistance of an endodontically treated tooth was increased by preparing the conservative endodontic cavity. The fracture of the maxillary first molar originated from the mesial groove of the enamel, propagated through the groove, and finally induced the damage in the dentin.  相似文献   

8.

Statement of problem

Different factors influence the degree of deviation in dental implant position after computed tomography–guided surgery. The surgical guide–manufacturing process with desktop 3D printers is such a factor, but its accuracy has not been fully evaluated.

Purpose

The purpose of this in vitro study was to evaluate the deviation in final dental implant position after the use of surgical guides fabricated from 2 different desktop 3D printers using a digital workflow.

Material and methods

Twenty 3D-printed resin models were prepared with missing maxillary premolar. After preoperative planning, 10 surgical guides were produced with a stereolithography printer and 10 with a digital light-processing (DLP) printer. A guided surgery was performed; 20 dental implants (3.8×12 mm) were installed, and a digital scan of the dental implants was made. Deviations between the planned and final position of the dental implants were evaluated for both the groups.

Results

A statistically significant difference between stereolithography and DLP were found for deviation at entry point (P=.023) and the vertical implant position (P=.009). Overall lower deviations were found for the guides from the DLP printer, with the exception of deviation in horizontal implant position.

Conclusions

The tested desktop 3D printers were able to produce surgical guides with similar deviations with regard to the final dental implant position, but the DLP printer proved more accurate concerning deviations at entry point and vertical implant position.  相似文献   

9.

Objective

To evaluate the quality of life in patients with moderate or large cranial bone defects before and after late cranioplasty.

Methods

Authors performed a prospective clinical trial including all consecutive patients that filled inclusion criteria during a period of 1 year. All patients answered the quality of life SF-36 questionnaire in 5 different times. Besides authors gathered information about the primary trauma and demographic characteristics.

Results

A total of 70 consecutive patients were admitted to the hospital during the study period, and 62 were included in the project. Cranioplasty statistically improved patients' quality of life in all 8 domains after a 24 months follow-up.

Conclusion

Cranioplasty has a significant impact over the quality of life in brain trauma victims who survived the primary trauma and harbor a large cranial bone defect.  相似文献   

10.

Background

Promoting the directional attachment of gingiva to the dental implant leads to the formation of tight connective tissue which acts as a seal against the penetration of oral bacteria. Such a directional growth is mostly governed by the surface texture.

Material and methods

In this study, three different methods, mechanical structuring, chemical etching and laser treatment, have been explored for their applicability in promoting cellular attachment and alignment of human primary gingival fibroblasts (HGFIBs).

Results

The effectiveness of mechanical structuring was shown as a simple and a cost-effective method to create patterns to align HGIFIBs.

Conclusion

Combining mechanical structuring with chemical etching enhanced both cellular attachment and the cellular alignment.  相似文献   

11.

Statement of problem

Excess cement around dental implants is a significant cause of peri-implant inflammation. Research has focused on approaches to cement removal, the type of cement used, and the different instruments used for cement removal with titanium abutments. However, data comparing zirconia with titanium abutments are lacking.

Purpose

The purpose of this in vitro study was to compare the effectiveness of excess cement removal from zirconia and titanium custom abutments using an explorer and to compare the effects of cement removal on the abutment surfaces.

Material and methods

Implant analogs were placed in a cast in the position of the 2 maxillary central incisors. After creating similar emergence profiles for both the implant abutments, 18 zirconia and titanium custom abutments were fabricated with 1-mm subgingival finish lines on the facial and interproximal areas and an equigingival finish line on the palatal side. The crowns were cemented with zinc oxide-eugenol cement, and a steel explorer was used to remove the excess cement. All abutments were analyzed under a scanning electron microscope for cement remnants and scratches.

Results

The mean surface area of cement remnants on the zirconia abutments was 778 ±113 μm2, and for titanium abutments, it was 1123 ±252 μm2, which in terms of the mean percentage area was 3.27% of the total surface area of zirconia and 4.71% of titanium abutments. Only a few abutments from each group showed scratches, and no deep scratches or gouges were observed.

Conclusions

Zirconia and titanium abutments had statistically similar cement remnants. Scratches were observed on only a few specimens.  相似文献   

12.

Introduction

Regenerative endodontic procedures (REP) are a novel treatment modality to restore the function of necrotic pulp tissue via stimulation or transplantation of stem cells into the root canal. This study aimed to investigate the immunohistologic outcome of 3 extracted teeth because of sequelae of trauma and unsatisfactory REP outcomes.

Methods

Three immature permanent maxillary central incisors of 3 female patients (6–9 years) were extracted 5.5–22 months after REP. Additionally, 1 sound permanent immature central maxillary incisor of 1 of the included patients was extracted for orthodontic reasons. The teeth were immunohistologically stained with Masson's trichrome, neurofilament (NF), pan cytokeratin, dentin sialophosphoprotein, and Gram+/-.

Results

The REP-teeth presented intracanalar vascularized connective/mineralized reparative tissue (RT), which was less organized than the pulp tissue of the sound tooth. Moderate to considerable calcification was observed below the Portland cement used during REP. In 1 case, the RT was NF+; in the 2 other cases, the periodontal ligament and apical granuloma/papilla were NF+. All teeth were Gram+/- negative; nevertheless, inflammatory cells were present in 2 cases. The pan cytokeratin and dentin sialophosphoprotein stainings were not specific enough for 2 cases.

Conclusions

This immunohistologic study of failed REP cases resulted in bacteria-free intracanalar RT and biomaterial-induced calcification. Nevertheless, the presence of inflammatory cells revealed a persistent inflammation. Hence, the clinical and radiographic signs were decisive for tooth survival and multidisciplinary outcome determination.  相似文献   

13.

Purpose

The aim of this study was to evaluate the population of CD8+ and natural killer (NK) cells in samples of oral (OSCC) and oropharyngeal (OPSCC) squamous cell carcinoma.

Patients and methods

Fifty-four cases squamous cell carcinoma (42 OSCC and 12 OPSCC) were immunohistochemically treated by CD8 and CD57 monoclonal antibodies. It was evaluated the relationship of CD8+ and NK cells with tumor size, lymph node metastasis (LNM), clinical staging (CS), overall survival (OS) and disease-free survival (DFS).

Results

Only CD8 was higher expressed in both tumors T1 and T2 than T3 and T4, as well as in tumours without LNM and with CS II or III (P < 0.05). There was no association with OS and DFS of both biomarkers.

Conclusions

These findings suggest that the differential CD8+ cells infiltration in OSCC and OPSCC might reflect a distinctive tumor microenvironment with a favorable local cytotoxic immune response against neoplastic cells.  相似文献   

14.

Background

Several significant issues on clinical trials reporting the effect of arginine-containing dental products have been addressed in systematic reviews and meta-analyses identifying the need for high-quality randomized clinical trials. A further methodological analysis of the given systematic reviews with meta-analysis on arginine products might provide information for future high-quality randomized clinical trials and current clinical practice.

Objective(s)

The objective was to perform a meta-epidemiological assessment of meta-analyses reporting the anticaries effect of arginine-containing formulations.

Methods

The data on risk-of-bias assessment, effect size measure, dispersion of estimated precision, and follow-up period were summarized for the meta-epidemiological review analysis.

Results

Studies with larger magnitude of effect sizes might present with unclear random sequence generation and unclear allocation concealment representing the selection bias. There was a significant strong negative correlation between the follow-up time and dispersion of precision estimates (rs = ?0.79, P = .034).

Conclusion

Results show that clinical trials on arginine dental products have methodological shortcomings. Both the selection bias and follow-up period influence the effect size magnitude and subsequent precision dispersion during evidence synthesis in clinical trials on arginine-containing dental products.  相似文献   

15.

Background

Specialty-based practice is a fundamental component of US medicine and dentistry, yet the recognition of new dental specialties has markedly diminished in the past 50 years while medical specialization has flourished.

Methods

This article reviews the history of specialty development while focusing on the underlying scientific, educational, and cultural changes in both professions. The process of dental specialty recognition is also examined.

Results

The current dental specialty recognition process provides a set of criteria aspiring specialties need to fulfill at the time of application, yet the relationship between the criteria and the sequence for attaining them is undefined. Scientific development and evidence-based practice have grown to become the cornerstone of contemporary health care specialization.

Conclusions

A new paradigm for specialty and subspecialty development in dentistry is needed. A model is presented herein that recognizes scientific development as the basis for specialization and describes a formal, sequenced process for the development of emerging specialties and subspecialties.

Practical Implications

This new paradigm for dental specialty recognition builds on the current criteria for specialization while encouraging cross-disciplinary interaction and nurturing the development of emerging specialties and subspecialties in dentistry. Doing so will allow dentistry to maintain its lead role in the maintenance of oral health and oral disease treatment in the US population.  相似文献   

16.

Introduction

The aim of this study was to assess whether laser Doppler flowmetry is more accurate than the conventional pulp sensibility tests (electric pulp test and ethyl chloride) in assessing the pulpal status of permanent anterior teeth in children and to identify the laser Doppler flowmetry’s Flux cut-off threshold.

Methods

A cross-sectional diagnostic accuracy study with randomization was performed and included 74 participants (8- to 16-year-old children). Participants had 1 maxillary central or lateral incisor with either a completed root canal treatment or an extirpated pulp and a contralateral tooth with vital pulp. Outcome measures included the sensitivity, specificity, and predictive values as well as the repeatability of all tests.

Results

A significant difference between the Flux values for teeth with vital and non-vital pulps was found. The cut-off ratio for laser Doppler flowmetry was 0.6, yielding a sensitivity of 53% and a specificity of 33%, which were lower than the values of the electric pulp test (sensitivity = 83.8%–94.6% and specificity = 89.2%–97.6%) and ethyl chloride (sensitivity = 81.1%–91.9% and specificity = 73%–81.1%). The repeatability of laser Doppler flowmetry, electric pulp testing, and ethyl chloride were 0.85, 0.86, and 0.81, respectively.

Conclusions

Laser Doppler flowmetry was unable to differentiate between teeth with vital and non-vital pulps. The results of this study showed that there was a high probability for false results. Further development of laser Doppler flowmetry in assessing pulpal blood flow would be required before it could be recommended for clinical use, especially in children.  相似文献   

17.

Statement of problem

Zirconia is a widely used restorative material. However, phase transformation on clinical application of zirconia has not yet been studied.

Purpose

The purpose of this study was to evaluate the wear, surface roughness, and aging associated with polished translucent zirconia in both in vitro and clinical experiments.

Material and methods

In vitro experiments were performed with Rainbow and Katana zirconia blocks and natural tooth enamel as the control. They were subjected to 100 000 loading cycles with a maxillary premolar antagonist. All specimens were analyzed for wear, and the zirconia specimens were evaluated for surface roughness and monoclinic phase (m-phase) transformation by X-ray diffractometry before and after cyclic loading. The clinical study included participants who required single-crown implant-supported restorations replacing the first or second molar. The participants received Rainbow or Katana zirconia prostheses (n=15, each). For wear analysis, impressions of each prosthesis, antagonist, and adjacent tooth were made at 1 week and 6 months after crown delivery. The occlusal relationship of the crowns in maximum intercuspation was evaluated by using the T-Scan 8 occlusal diagnostic system. The degree of transformation of zirconia to the m-phase was measured by using X-ray diffractometry of the crowns after 6 months of use.

Results

Zirconia induced significantly greater enamel wear than the natural tooth control. Katana specimens exhibited significantly greater wear and surface roughness than the Rainbow specimens. The degrees of antagonistic wear and zirconia phase transformation in the clinical experiment were significantly greater than those in the in vitro experiment. The Katana groups showed significantly higher m-phase levels than the Rainbow groups.

Conclusions

Phase transformation of zirconia occurs within 6 months of clinical use, and the wear and degrees of phase transformation varied according to the zirconia product used.  相似文献   

18.

Background

This study was undertaken to quantify how the Great Recession impacted the demand for general oral health care and orthodontic care in the United States. The authors conducted an analysis to help dentists anticipate changes in demand for care during future economic downturns.

Methods

The authors analyzed Medical Expenditure Panel Survey data for the period 2003 through 2015. Data plotting for the various factors considered showed patient demand before, during, and after the Great Recession, including an indication of postrecession recovery. Statistical significance across time was determined using a χ2 test. The point estimates and statistical inferences took into account the complex survey design of the Medical Expenditure Panel Survey.

Results

General dentist visits declined slowly and steadily during the Great Recession, reaching a low of 38.4% in 2010, and have not shown significant signs of recovery. Orthodontic visits also declined to an all-time low of 2.5% in 2010, although they have somewhat recovered. Out-of-pocket expenditures were lower in 2015 than in 2003 for general dental and orthodontic care.

Conclusion

The effects of the Great Recession resulted in a decrease in the demand for oral health care, differing for general oral health care and orthodontic care.

Practical Implications

These findings, especially in combination with leading indicators for economic downturns, will allow dentists to better plan and use strategies for maintaining practice stability during periods of reduced demand for care.  相似文献   

19.

Statement of problem

A palatogram aids prosthodontists and speech pathologists in evaluating the precise prosthetic treatment needed and the effectiveness of such treatment to improve speech intelligibility. Powder is commonly used to visualize tongue-palate contact, where wetted areas of powder in the oral cavity reveal such contact during palatography. However, discomfort and the risk of aspiration are among the shortcomings of this method, and an improved method is needed.

Purpose

The purpose of this in vitro study was to examine the feasibility of a new method of palatography that uses airborne-particle–abraded acrylic resin so that wet areas can be easily distinguished from dry areas.

Material and methods

Seventy-two specimens of heat-polymerized acrylic resin were prepared in 6 different resin colors. After the specimens had been airborne-particle abraded, CIELab color values for each specimen were measured using a colorimeter under dry and wet conditions and recorded. Color difference (ΔE) was then computed, and a paired Student t test, 1-way analysis of variance, and multiple comparison using the Tukey post hoc analysis were applied (α=.05).

Results

A significant color difference was found between the 2 conditions in all acrylic resin specimens examined. Mean ΔE ranged from 5.58 to 6.76.

Conclusions

The results indicated that an airborne-particle–abraded acrylic resin surface can show color differences made by wetting on palatograms.  相似文献   

20.

Purpose

Successful implant therapy is based on fast, safe, and predictable osseointegration. Several surface modifications have been introduced to improve the bone-to-implant interaction. This in vivo study evaluates the impact of plasma surface conditioning on early wound healing and osseointegration.

Materials and methods

A total of 16 dental implants with a sand-blasted and acid-etched surface were conditioned with cold atmospheric plasma prior to insertion in the frontal bone of four miniature pigs. Sequential fluorescence labeling was administered to label bone metabolism, and after 8 weeks, bone blocks were harvested for radiological, histological, and histomorphometrical evaluation.

Results

The plasma conditioning had no impact on the morphology of the implant surface. The bone-to-implant contact ratio was 90.4% and 86.5%, the interthread bone density 72.5% and 63.4%, and the periimplant bone density 60.5% and 61.1%, in the plasma conditioned group and control group, respectively. Concentric bands of fluorescence enrichment indicated a chronological and homogenous mineralization of newly formed bone. No unwanted periimplant side effects were detected.

Conclusion

The increased parameters for osseointegration in this in vivo study merit further investigation in prospective clinical trials.  相似文献   

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