Bone healing pattern in surgically created circumferential defects around submerged implants: an experimental study in dog

Objective: To describe the healing of marginal defects below or above 1 mm of dimension around submerged implants in a dog model. Material and methods: In 12 Labrador dogs, all mandibular premolars and first molars were extracted bilaterally. After 3 months of healing, full‐thickness flaps were elevated in the edentulous region of the right side of the mandible. Two recipient sites were prepared and the marginal 5 mm were widened to such an extent to obtain, after implant installation, a marginal gap of 0.5 mm at the mesial site (small defect) and of 1.25 mm at the distal site (large defect). Titanium healing caps were affixed to the implants and the flaps were sutured allowing a fully submerged healing. The experimental procedures were subsequently performed in the left side of the mandible. The timing of the experiments and sacrifices were planned in such a way to obtain biopsies representing the healing after 5, 10, 20 and 30 days. Ground sections were prepared and histomorphometrically analyzed. Results: The filling of the defect with newly formed bone was incomplete after 1 month of healing in all specimens. Bone formation occurred from the base and the lateral walls of the defects. A larger volume of new bone was formed in the large compared with the small defects. Most of the new bone at the large defect was formed between the 10‐ and the 20‐day period of healing. After 1 month of healing, the outline of the newly formed bone was, however, located at a similar distance from the implant surface (about 0.4 mm) at both defect types. Only minor newly formed bone in contact with the implant, starting from the base of the defects, was seen at the large defects (about 0.8 mm) while a larger amount was detected at the small defects (about 2.2 mm). Conclusion: Marginal defects around titanium implants appeared to regenerate in 20–30 days by means of a distance osteogenesis. The bone fill of the defects was, however, incomplete after 1 month. To cite this article:
Rossi F, Botticelli D, Pantani F, Pereira FP, Salata LA, Lang NP. Bone healing pattern in surgically created circumferential defects around submerged implants: an experimental study in dog.
Clin. Oral Impl. Res 23 , 2012; 41–48.
doi: 10.1111/j.1600‐0501.2011.02170.x     

“Denture Marking” as an Aid to Forensic Identification

??Identification through forensic science is an art of giving the corpse a name A real life detective work that would put even Sherlock Homes to shame.?? Forensic dentistry deals with proper handling and examination of dental evidence and proper evaluation and presentation of dental findings in interest of justice. Denture marking or labeling is not a new concept in either Prosthetic or Forensic dentistry and its routine practice has been urged by Forensic dentists internationally for many years. Denture marking is accepted as a means of identifying dentures and persons in geriatric institutions or post mortem during war, crimes, and civil unrest, natural and mass disasters. Prosthodontists are playing very important role in forensic dentistry as they are concerned with fabrication of various prostheses which can serve as an important tool for identification. Identification is essential requirement of any medico-legal investigation because a wrong identity may pose a problem in delivering justice. The main objective of this article is to discuss the various methods of denture marking and to emphasize the importance of denture marking for person identification in medico legal investigations.     

Regular and platform switching: bone stress analysis varying implant type

Purpose: This study aimed to evaluate stress distribution on peri‐implant bone simulating the influence of platform switching in external and internal hexagon implants using three‐dimensional finite element analysis. Materials and Methods: Four mathematical models of a central incisor supported by an implant were created: External Regular model (ER) with 5.0 mm × 11.5 mm external hexagon implant and 5.0 mm abutment (0% abutment shifting), Internal Regular model (IR) with 4.5 mm × 11.5 mm internal hexagon implant and 4.5 mm abutment (0% abutment shifting), External Switching model (ES) with 5.0 mm × 11.5 mm external hexagon implant and 4.1 mm abutment (18% abutment shifting), and Internal Switching model (IS) with 4.5 mm × 11.5 mm internal hexagon implant and 3.8 mm abutment (15% abutment shifting). The models were created by SolidWorks software. The numerical analysis was performed using ANSYS Workbench. Oblique forces (100 N) were applied to the palatal surface of the central incisor. The maximum (σ_max) and minimum (σ_min) principal stress, equivalent von Mises stress (σ_vM), and maximum principal elastic strain (ε_max) values were evaluated for the cortical and trabecular bone. Results: For cortical bone, the highest stress values (σ_max and σ_vm) (MPa) were observed in IR (87.4 and 82.3), followed by IS (83.3 and 72.4), ER (82 and 65.1), and ES (56.7 and 51.6). For ε_max, IR showed the highest stress (5.46e‐003), followed by IS (5.23e‐003), ER (5.22e‐003), and ES (3.67e‐003). For the trabecular bone, the highest stress values (σ_max) (MPa) were observed in ER (12.5), followed by IS (12), ES (11.9), and IR (4.95). For σ_vM, the highest stress values (MPa) were observed in IS (9.65), followed by ER (9.3), ES (8.61), and IR (5.62). For ε_max, ER showed the highest stress (5.5e‐003), followed by ES (5.43e‐003), IS (3.75e‐003), and IR (3.15e‐003). Conclusion: The influence of platform switching was more evident for cortical bone than for trabecular bone, mainly for the external hexagon implants. In addition, the external hexagon implants showed less stress concentration in the regular and switching platforms in comparison to the internal hexagon implants.     

Practical skills training influences knowledge and attitude of dental students towards emergency medical care

Background: Medical emergencies in dental practice are generally perceived as being rare. Nonetheless, recent studies have shown that incidents occur on a regular basis. Therefore, patients have the right to expect necessary skills to manage life‐threatening situations from every dentist. Objective: To observe students’ attitude and self‐assessment towards emergency medical care (EMC) and its practical appliance. Material and methods: Students of dentistry took part in small group sessions for adult and paediatric basic life support. Participants filled out pre–post questionnaires regarding knowledge and attitude towards EMC (6, respectively, 10‐point Likert scale). Additionally, feedback was asked for the quality of course and tutors. Results: Forty dental students in their last 2 years of study registered for the EMC courses. The majority had never attended any first‐aid course; the mean age was 25% and 75% were women. A comparison between pre‐ and post‐evaluation showed that the participation in practical training easily enhances the students’ awareness of EMC importance as well as self‐confidence in managing emergencies. After the course, 71% shared the opinion that retraining should be obligatory for all medical personnel. At the same time, students’ self‐assessment of confidence for specific tasks got significant upgrades in every aspect. Conclusion: The evaluation data clearly show the participants’ needs to deal with topics of EMC within the curriculum of dentistry. The proposed course is able to change participants’ attitudes towards EMC and its importance for their daily practice. The considerable enhancement of self‐confidence in performing EMC‐techniques might also lead to more willingness to manage emergency situations.     

Evaluation of Dimensional Accuracy of Panoramic Cross‐Sectional Tomography,Its Ability to Identify the Inferior Alveolar Canal,and Its Impact on Estimation of Appropriate Implant Dimensions in the Mandibular Posterior Region

Objectives: To evaluate the dimensional accuracy of panoramic cross‐sectional tomography, its impact on implant size estimation and its ability in identifying the inferior alveolar canal in the mandibular posterior region. Material and Methods: Eight partially edentulous mandibles with 18 edentulous sites were obtained. Orthopantomograms and tomograms were made and the mandible's outline and the position of mandibular canals on tomograms were traced on a clear acetate paper. Horizontal and vertical magnification factors were calculated. The mandibular height, distance between mandibular canal and alveolar crest, maximum bucco‐lingual width, distance between buccal cortex and mandibular canal, and cortical thickness at the inferior border of the mandible were measured. Potential implant sites were identified and implant sizes were estimated. Location and visibility of mandibular canals were also evaluated. The mandibles were sectioned at each site and all the above mentioned parameters were assessed which served as gold standard. Results: Mean horizontal and vertical magnification factors were 1.47 ± 0.048 and 1.53 ± 0.038. Total height and maximum bucco‐lingual width were underestimated by 1.88% and 1.59%. Crest to canal distance, cortical thickness at the inferior border of the mandible and buccal cortex to mandibular canal were overestimated by 0.59%, 5.16%, and 3.64%. Implant sizes were estimated for 11 sites and changes were recorded at 2 sites between record 1 and record 2. However, there was no disagreement between record 2 and record 3. Of the canals, 61.11% were located lingually and the visibility of mandibular canals was poor in 44.44% of cases. Conclusions: The tomograms were found to be accurate for the measurements in both horizontal and vertical planes and reliable for implant size estimation, taking into consideration proper magnification factors. They were also found to be useful in assessing the location of mandibular canal but were not very effective in discerning it.     

Dental hygienists as adult learners and educators to improve access to care

To cite this article:
Int J Dent Hygiene 10 , 2012; 36–45
DOI: 10.1111/j.1601‐5037.2011.00510.x
Rogo EJ. Dental hygienists as adult learners and educators to improve access to care. Abstract: Objective: The purpose of the qualitative study was to understand dental hygienists as adult learners and educators in their quest to improve access to care. The intent of this article is to share the results from open and focused coding procedures and the participants’ rich stories from which the analysis was constructed. Methods: A grounded theory approach to data collection and analysis was used. Data were collected from eight practitioners in three US states who met the inclusion criteria, using semi‐structured interviews. Traditional grounded theory procedures with a constructivist emphasis on lived experiences of the participants and situational analysis were used to analyse the data. Results: The process of learning was experienced in three categories: Awareness, Adaptation and Relationships. Awareness was the process of learning participants experienced as developing consciousness of self, status quo, power and injustice of systems. Adaptation was constructed from experiences of specializing and creating to adjust to the new environments and prepare future practitioners. Relationships were developed to feel connected and collaborate to build support and gain respect to improve access to care. Dental hygienists as educators revealed one category: Improvement. Improvement was the process of educating others to enhance awareness, oral health and the dental hygiene profession. Conclusions: Dental hygienists were adult learners by using their experiences in the context of their struggle to improve health inequities. A strong educator role was necessary to make improvements in the oral health delivery system.     

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数字化口腔医学是口腔医学的主要发展方向之一,其中以计算机技术为核心的数字化制造技术采用不同的制造工艺、材料,可广泛满足口腔医学多个领域的临床需求,本文就此专题进行概述.     

A 24-month evaluation of amalgam and resin-based composite restorations: Findings from The National Dental Practice-Based Research Network

BackgroundKnowing which factors influence restoration longevity can help clinicians make sound treatment decisions. The authors analyzed data from The National Dental Practice-Based Research Network to identify predictors of early failures of amalgam and resin-based composite (RBC) restorations.MethodsIn this prospective cohort study, the authors gathered information from clinicians and offices participating in the network. Clinicians completed a baseline data collection form at the time of restoration placement and annually thereafter. Data collected included patient factors, practice factors and dentist factors, and the authors analyzed them by using mixed-model logistic regression.ResultsA total of 226 practitioners followed up 6,218 direct restorations in 3,855 patients; 386 restorations failed (6.2 percent) during the mean (standard deviation) follow-up of 23.7 (8.8) months. The number of tooth surfaces restored at baseline helped predict subsequent restoration failure; restorations with four or more restored surfaces were more than four times more likely to fail. Restorative material was not associated significantly with longevity; neither was tooth type. Older patient age was associated highly with failure (P N/A .001). The failure rate for children was 4 percent, compared with 10 percent for people 65 years or older. Dentist’s sex and practice workload were associated significantly with restoration longevity.ConclusionsIn this prospective cohort study, these factors were significantly predictive of failure for amalgam and RBC restorations: patient’s age, a higher number of surfaces restored at baseline, the dentist’s sex and the practice workload. Material choice was not significantly predictive in these early results.Practical ImplicationsIf clinicians can recognize and identify the risk factors associated with early restoration failure, more effective treatment plans may be offered to the patient.     

Patient safety incident prevention and management among Finnish dentists

Abstract

Objective. Assessing current patient safety incident (PSI) prevention measures and risk management practices among Finnish dentists. Materials and methods. A total of 1041 dentists practicing in the private or public sectors in southern Finland completed an online questionnaire concerning PSI prevention, PSI-reporting systems, feedback and knowledge gained from device incidents and patient-generated safety information and the knowledge of national PS-guidance. The answers were handled anonymously. Statistical evaluations were performed using chi-square analysis. Results. Dentists suggested multiple methods for preventing PSIs related to dental diagnostics, various treatments, equipment and devices, medications, communication, infection control and general practice safety. Preventive methods reported most frequently included working with caution and forethought, keeping accurate patient records and the availability of correct patient information. A special PSI-reporting system was used by less than one third of respondents. Feedback received on PS-related data and the utilization of guidebooks varied significantly between the studied dentist groups. Conclusions. Several PSI prevention techniques are already used in Finland. However, wide variation exists in PSI prevention and risk management practices among Finnish dentists. Systematic implementation of available safety methods would probably prevent several PSIs. The results indicate that the more dentists know about PS risks, the easier it is for them to recognize situations possibly leading to patient harm. Anonymous PSI reports, patient complaints and claims data should, therefore, be actively used for mutual learning. Increased PS education in dentistry is also needed.