Systemic management and periodontal treatment of HIV-necrotizing periodontitis: A case report.

BACKGROUND: Necrotizing periodontitis (NP) is a rare form of periodontal disease. It can manifest in immunocompromised patients and present as painful and rapidly progressing destruction with necrotic and ulcerated periodontal tissues. This case report describes a rare case of severe NP in human immunodeficiency virus (HIV)-positive patient including medical management and periodontal treatment. METHODS: A 28-year-old male presented to the periodontal clinic with chief complaint of severe oral pain leading to loss of chewing ability, spontaneous gingival bleeding, generalized gingival recession, tooth mobility, and dentinal hypersensitivity. Clinical and radiographic examination revealed generalized tissue necrosis with severe periodontal destruction, extensive bleeding, spontaneous suppuration, and heavy biofilm. RESULTS: Medical history was positive for perinatal HIV infection, which was treated and patient was asymptomatic until he discontinued antiviral medications nine years ago. Following initial examination, patient was referred to the Infectious disease clinic and multidisciplinary management was initiated with comprehensive management of primary disease including systemic antiviral, antibiotic, and antifungal therapy to establish immunocompetence compatible with providing mechanical nonsurgical periodontal treatment. CONCLUSIONS: This case report highlights a severe and generalized form of NP in an HIV patient due to the cessation of antiviral therapy. Favorable course of interdisciplinary medical and periodontal therapy resulted in significant improvement in patient's systemic, oral, and periodontal health.

Influence of Metal Guide Sleeves on the Accuracy and Precision of Dental Implant Placement Using Guided Implant Surgery: An In Vitro Study.

PURPOSE: Metal sleeves are commonly used in implant guides for guided surgery. Cost and sleeve specification limit the applications. This in vitro study examined the differences in the implant position deviations produced by a digitally designed surgical guide with no metal sleeve in comparison to a conventional one with a metal sleeve. MATERIALS AND METHODS: The experiment was conducted in two steps for each step: n = 20 casts total, 10 casts each group; Step 1 to examine one guide from each group with ten implant placements in a dental cast, and Step 2 to examine one guide to one cast. Implant placement was performed using a guided surgical protocol. Postoperative cone-beam computed tomography images were made and were superimposed onto the treatment-planning images. The implant horizontal and angulation deviations from the planned position were measured and analyzed using t-test and F-test (p = 0.05). RESULTS: For Step 1 and 2, respectively, implant deviations for the surgical guide with sleeve were -0.3 ±0.17 mm and 0.15 ±0.23 mm mesially, 0.60 ±1.69 mm, and -1.50 ±0.99 mm buccolingual at the apex, 0.20 ±0.47 mm and -0.60 ±0.27 mm buccolingual at the cervical, and 2.73° ±4.80° and -1.49° ±2.91° in the buccolingual angulation. For Step 1 and 2, respectively, the implant deviations for the surgical guide without sleeve were -0.17 ±0.14 mm and -0.06 ±0.07 mm mesially, 0.35 ±1.04 mm and -1.619 ±1.03 mm buccolingual at the apex, 0.10 ±0.27 mm and -0.62 ±0.27 mm buccolingual at the cervical, and 1.73° ±3.66° and -1.64° ±2.26° in the buccolingual angulation. No statistically significant differences were found in any group except for mesial deviation of the Step 2 group (F-test, p < 0.001). CONCLUSIONS: A digitally designed surgical guide with no metal sleeve demonstrates similar accuracy but higher precision compared to a surgical guide with a metal sleeve. Metal sleeves may not be required for guided surgery.

Implant Site Preparation Application of Injectable Platelet-Rich Fibrin for Vertical and Horizontal Bone Regeneration: A Clinical Report.

Guided bone regeneration (GBR) using a combined injectable platelet-rich fibrin (i-PRF), leukocyte- and platelet-rich fibrin (L-PRF), and biocompatible bone substitute material, is a convenient and effective method to augment a combined vertical and horizontal bone defect. This approach can create sufficient bone quality and quantity for implant surgical sites. A 55-year-old Asian woman presented with a severe bone defect in posterior mandible. The edentulous mandibular alveolar ridge was severely resorbed vertically and horizontally. A GBR procedure using i-PRF and L-PRF combined with particulate bone graft was performed. Postoperative cone beam computed tomography scans, 8 months after the augmentation, revealed a large regeneration of the alveolar bone sufficient for implant placement. A combination i-PRF/L-PRF and particulate bone graft may provide biologically active molecules and a scaffold for osteogenesis. This treatment protocol may be a viable option for a large bone defect required augmentation before implant placement.

Tracking Tag Stabilization With a Small-Diameter Implant in an Edentulous Mandible to Assist Dynamically Navigated Surgery: A Case Report.

This report describes the use of a temporary dental implant to secure a radiographic fiducial marker and patient-tracking tag to an edentulous mandible for dynamically guided implant placement into a fibula microvascular free flap. A small-diameter dental implant was placed into the anterior mandible to secure a radiographic fiducial marker followed by a patient tag. The patient tag allowed for tracking of the patient's mandible during placement of endosseous dental implants. Four endosseous dental implants were successfully placed into the edentulous fibula free flap mandibular reconstruction. Dynamic navigation using a small-diameter implant to secure radiographic fiducial markers and patient tags provides a novel technique to place implants into an edentulous microvascular free flap with minimal incision and reflection of soft tissue.

Odontogenic Keratocyst Is Frequently Misdiagnosed for a Lateral Periodontal Cyst in Premolar and Anterior Tooth-Bearing Areas.

INTRODUCTION: Radiolucent lesions with gingival swelling found in the premolar and intercanine region can elicit a different clinical diagnosis than one confirmed by histologic findings. The purpose of the study is to identify and present the frequency of the unexpected microscopic diagnosis of odontogenic keratocyst (OKC) in a location preoperatively favoring a lateral periodontal cyst (LPC) with similar clinical and radiographic appearance. METHODS: A retrospective analysis of biopsies received from 2011 and 2019 was performed, and the number of LPC and OKC cases was assessed. The alignment of clinical and radiographic diagnosis to histologic findings and anatomic location was analyzed, and the number of OKC cases preoperatively misdiagnosed as LPCs was identified. RESULTS: A total of 79,257 biopsies were received. Of those, 184 were diagnosed as LPCs and 742 as OKCs. For all preoperatively diagnosed LPCs, the clinical and histologic diagnosis aligned; however, 182 of 742 OKCs were submitted with a clinical misdiagnosis of LPCs. The location of these lesions with the unanticipated diagnosis overlapped with those for LPCs, specifically the maxillary and mandibular anterior and premolar regions. CONCLUSIONS: Radiolucent lesions with gingival swelling in the premolar and intercanine region are frequently clinically and radiographically misdiagnosed. A biopsy should be considered in all cases to establish the correct pathologic diagnosis and treatment course.

In Vitro Comparison of Time and Accuracy of Implant Placement Using Trephine and Conventional Drilling Techniques Under Dynamic Navigation.

The aim of this randomized in vitro study was to compare the time and accuracy of implant-site preparation and implant placement using a trephine drill versus a conventional drilling technique under dynamic navigation. In total, 42 implants were placed in simulation jaw models with the 2 drilling techniques by 2 operators who had previous experience with dynamic navigation. The timing of each implant placement was recorded, and horizontal, vertical, and angulation discrepancies between the planned and placed implants were compared. There was no significant difference in time or accuracy between the trephine and conventional drilling techniques. Implant-site preparation with a single trephine drill using dynamic navigation was as accurate under in vitro experimental conditions as a conventional drilling sequence.

Effects of two Postprocessing Methods onto Surface Dimension of in-Office Fabricated Stereolithographic Implant Surgical Guides.

PURPOSE: To evaluate the effects of two postprocessing methods in terms of the overall, intaglio, and cameo surface dimensions of in-office stereolithographic fabricated implant surgical guides. MATERIALS AND METHODS: Twenty identical implant surgical guides were fabricated using a stereolithographic printer. Ten guides were postprocessed using an automated method. The other ten guides were postprocessed using a series of hand washing in combination with ultrasonics. Each guide was then scanned using cone-beam computed tomography to produce a set of digital imaging and communications in medicine (DICOM) files which were converted into standard tessellation language (STL) files. The STL file was then superimposed onto the original STL design file using the best fit alignment. The average positive and negative surface discrepancy differences in terms of means and variances were analyzed using t-test (α = 0.05). RESULTS: For the alternative group, the average positive and negative overall, intaglio, and cameo surface discrepancies were 77.38 ± 10.68 µm and -67.74 ± 6.55 µm; 78.83 ± 8.65 µm and -68.16 ± 5.26 µm; and 70.5 ± 8.48 µm -64.84 ± 5.55 µm, respectively. For the automated group, the average positive and negative overall, intaglio, and cameo surface discrepancies were 51.88 ± 4.38 µm and -170.7 ± 11.49 µm; 64.3 ± 4.44 µm and -89.45 ± 6.25 µm; and 83.59 ± 4.81 µm and -144.26 ± 13.19 µm, respectively. There was a statistical difference between the means of the two methods for the overall, intaglio, and cameo positive and negative discrepancies (p < 0.001). CONCLUSIONS: For a single implant tooth-supported implant guide, using hand washing with ultrasonics appeared to be consistently better than the automated method. The manual method presented with more positive discrepancies, while the automated method presented with more negative discrepancies.

Effect of biologic materials on the outcomes of horizontal alveolar ridge augmentation: A retrospective study.

PURPOSE: The purpose of this study was to investigate if the addition of biologic agents to a particulate bone graft enhances horizontal ridge augmentation outcomes in terms of bone dimensions, bone density, and successful implant placement. MATERIALS AND METHODS: A retrospective chart review was done to assess the clinical and radiographic outcomes in 52 horizontal ridge augmentation sites in 43 patients. Information was gathered regarding surgical technique, type of graft material, biologic agents used (PRP or rhPDGF-BB), method of space maintenance, and achieved alveolar ridge width and bone density changes as quantified on CBCT scans. RESULTS: The use of tenting screws, a resorbable membrane, and a combination of particulate allogenic and xenogenic bone graft material provided an average horizontal bone gain of 3.6 mm in the 52 augmented sites. There was no statistically significant difference observed in the amount of horizontal bone gain between sites treated with the addition of biologic agents (n = 21), or with a particulate bone graft alone (n = 31). A marginally statistically significant difference was found in the density of the grafted bone with the addition of biologics (p value = .0653). CONCLUSION: The addition of biologic agents to the graft materials did not have a significant effect on the amount of horizontal bone gain or successful implant placement; however, it marginally enhanced the bone density of the grafted area.

Oral Soft Tissue Grafting.

The presence of healthy soft tissue at the tooth and implant interface correlates to long-term success and stability in function and esthetics. Grafting procedures utilizing various techniques can be performed during any stage of the implant or restorative therapy. Materials of autogenous, allogeneic, and xenogeneic sources are available for oral soft tissue grafting. This article describes the classifications of soft tissue defects, treatment modalities, and materials used to enhance soft tissue quality and quantity and to achieve optimal esthetics and function around teeth and implants.

Accuracy and precision of 3D-printed implant surgical guides with different implant systems: An in vitro study.

STATEMENT OF PROBLEM: Implant guided surgery systems promise implant placement accuracy and precision beyond straightforward nonguided surgery. Recently introduced in-office stereolithography systems allow clinicians to produce implant surgical guides themselves. However, different implant designs and osteotomy preparation protocols may produce accuracy and precision differences among the different implant systems. PURPOSE: The purpose of this in vitro study was to measure the accuracy and precision of 3 implant systems, Tapered Internal implant system (BioHorizons) (BH), NobelReplace Conical (Nobel Biocare) (NB), and Tapered Screw-Vent (Zimmer Biomet) (ZB) when in-office fabricated surgical guides were used. MATERIAL AND METHODS: A cone beam computed tomography (CBCT) data set of an unidentified patient missing a maxillary right central incisor and intraoral scans of the same patient were used as a model. A software program (3Shape Implant Studio) was used to plan the implant treatment with the 3 implant systems. Three implant surgical guides were fabricated by using a 3D printer (Form 2), and 30 casts were printed. A total of 10 implants for each system were placed in the dental casts by using the manufacturer's recommended guided surgery protocols. After implant placement, postoperative CBCT images were made. The CBCT cast and implant images were superimposed onto the treatment-planning image. The implant positions, mesiodistal, labiopalatal, and vertical, as well as implant angulations were measured in the labiolingual and mesiodistal planes. The displacements from the planning in each dimension were recorded. ANOVA with the Tukey adjusted post hoc pairwise comparisons were used to examine the accuracy and precision of the 3 implant systems (α=.05). RESULTS: The overall implant displacements were -0.02 ±0.13 mm mesially (M), 0.07 ±0.14 mm distally (D), 0.43 ±0.57 mm labially (L), and 1.26 ±0.80 mm palatally (P); 1.20 ±3.01 mm vertically in the mesiodistal dimension (VMD); 0.69 ±2.03 mm vertically in the labiopalatal dimension (VLP); 1.69 ±1.02 degrees in mesiodistal angulation (AMD); and 1.56 ±0.92 degrees in labiopalatal angulation (ALP). Statistically significant differences (ANOVA) were found in M (P=.026), P (P=.001), VMD (P=.009), AMD (P=.001), and ALP (P=.001). ZB showed the most displacements in the M and vertical dimensions and the least displacements in the P angulation (P<.05), suggesting statistically significant differences among the M, VMD, VLP, AMD, and ALP. NB had the most M variation. ZB had the least P deviation. NB had the fewest vertical dimension variations but the most angulation variations. CONCLUSIONS: Dimensional and angulation displacements of guided implant systems by in-office 3D-printed fabrication were within clinically acceptable limits: <0.1 mm in M-D, 0.5 to 1 mm in L-P, and 1 to 2 degrees in angulation. However, the vertical displacement can be as much as 2 to 3 mm. Different implant guided surgery systems have strengths and weaknesses as revealed in the dimensional and angulation implant displacements.

Effect of postoperative steroids on clinical outcomes and radiographic findings of horizontal alveolar ridge augmentation: A retrospective study.

BACKGROUND: The purpose of the study was to investigate if the prescription of oral postoperative steroids has an effect on clinical outcomes of horizontal ridge augmentation including implant placement and characteristics of the grafted bone. METHODS: A retrospective chart review of 73 horizontal ridge augmentation cases was completed to assess the clinical outcomes, 53 of those cases were further assessed radiographically. Information was gathered regarding surgical technique, grafting materials, postoperative healing, medications used postoperatively, bone growth, and density changes as quantified on a cone-beam computed tomography (CBCT) scan. Statistical analysis was completed to identify whether the use of postoperative oral steroids altered outcomes. RESULTS: Steroids were used postoperatively following various horizontal ridge augmentation procedures. The use of tenting screws and resorbable membranes with a combination of osseous allograft and xenograft was used in 73 cases, 53 of which had preoperative and postoperative CBCT scans. Graft exposure occurred in five of the cases (9%), with the majority (n = 4) among those with postoperative steroids, but this was not statistically significant (P-value = 0.6510). Use of steroids was also not significantly associated with the number of courses of antibiotics (P-value > 0.05), but it was significantly associated with increased number of postoperative visits (P-value < 0.05). Among the subset for radiographic analysis (n = 53), there were significant clinical and radiographic dimensional changes in alveolar ridge width with an average horizontal bone gain of 3.6 mm. There were no statistically significant differences found in radiographic linear bone gain or clinical outcomes with the addition of steroids. A marginally statistically significant in the density of grafted bone was found with the addition of steroids (P-value > 0.05). CONCLUSION: The prescription of postoperative steroids did not make a significant difference in clinical outcomes, success of implant placement or on radiographic assessment of grafted sites following horizontal alveolar ridge augmentation.

Intaglio Surface Dimension and Guide Tube Deviations of Implant Surgical Guides Influenced by Printing Layer Thickness and Angulation Setting.

PURPOSE: To measure overall intaglio dimensional and tube deviations of implant guides printed at 50 and 100 µm layer thickness at 0°, 45°, and 90° angulation using a stereolithographic (SLA) printer. MATERIALS AND METHODS: A surgical implant guide design from a subject missing a maxillary right central incisor, used as the original standard tessellation language (STL) were stereolithographically fabricated at each thickness and angulation, 50 and 100 µm layer thickness at 0°, 45°, and 90° angulation (n = 10 each group). The guide was then scanned using cone beam computed tomography. The digital imaging and communications in medicine (DICOM) scanned files were then converted to an STL format. The overall dimensional deviations of the intaglio surface and the positioning of the implant guide tube were then superimposed onto the original designed STL file using best-fitting alignment. A t-test and an F-test as well as ANOVA followed by a post hoc t-test were used to determine statistical significant differences (α = 0.05) for the intaglio surface and guide tube deviation, respectively. RESULTS: The overall intaglio surface discrepancies (µm) printed at 0°, 45°, and 90° were 55.07 ± 1.36, 52.39 ± 2.09, and 61.02 ± 15.96 for 50 µm layer; and 98.38 ± 10.55, 84.47 ± 10.61, and 90.26 ± 5 for 100 µm layer with statistically significant differences for both t-test and F-test, p < 0.001. The maximal guide tube linear deviations (µm) printed at 0°, 45°, and 90° were 10.78 ± 3.84, 8.16 ± 3.68, and 12.57 ± 5.39 for 50 µm layer (ANOVA, p = 0.096); and 10.95 ± 5.23, 16.79 ± 4.97, and 22.63 ± 2.81 for 100 µm layer (ANOVA, p < 0.001). The maximal guide tube angular deviations (°) printed at 0°, 45°, and 90° were 1.29 ± 0.30, 0.64 ± 0.13, and 0.56 ± 0.21 for 50 µm layer (ANOVA, p < 0.001); and 1.57 ± 0.29, 0.86 ± 0.14, and 1.02 ± 0.31 for 100 µm layer (ANOVA, p = 0.034). There was a statistical difference in the deviations between 50 and 100 µm layer printing in all printed angulations except at 0° (t-test, p = 0.05, p = 0.03, and p = 0.001 for 0°, 45°, and 90°) and linear deviations (t-test, p < 0.001, p = 0.009, and p = 0.001 for 0°, 45°, and 90°). CONCLUSION: Printing at 50 µm layer reduces dimensional intaglio deviations in general and reduces tube angular deviations with different angulations of printing. However, the deviations were only ∼60 to 100 µm for the intaglio dimension deviations; and ∼0.04 to 0.26 mm and ∼0.25° to ∼2° for tube deviations.

Exploring training dental implant placement using computer-guided implant navigation system for predoctoral students: A pilot study.

INTRODUCTION: Recent computer-guided dynamic navigation systems promise a novel training approach for implant surgery. This study aimed to examine learning progress in placement of dental implants among dental students using dynamic navigation on a simulation model. MATERIALS AND METHODS: Senior students with no implant placement experience were randomly assigned five implant placement attempts involving either three maxillary or four mandibular implants distributed in the anterior/posterior, and left/right segments. Implant placement was planned using a Navident Dynamic Guidance system. Surgical time was recorded. Horizontal, vertical and angulation discrepancies between the planned and placed implant positions were measured using superimposed CBCT scans. Data were analysed with repeated measures regression with Tukey's adjusted pairwise comparisons (α = 0.05). RESULTS: Fourteen students participated, with a mean age of 26.1 years and equal males and females. Mean time for implant placement was associated with attempt number (P < 0.001), implant site (P = 0.010) and marginally related to gender (P = 0.061). Students had a significant reduction in time from their first attempt to their second (10.6 vs 7.6 minutes; adjusted P < 0.001) then plateaued. Overall 3D angulation (P < 0.001) and 2D vertical apex deviation (P = 0.014) improved with each attempt, but changes in lateral 2D (P = 0.513) and overall 3D apex deviations (P = 0.784) were not statistically significant. Implant sites were associated with lateral 2D, 2D vertical and overall 3D apex deviation (P < 0.001). DISCUSSION: Males were marginally faster than females, had slightly lower overall 3D angulation, and reported higher proficiency with video games. Novice operators improved significantly in speed and angulation deviation within the first three attempts of placing implants using dynamic navigation. CONCLUSION: Computer-aided dynamic implant navigation systems can improve implant surgical training in novice population.

Discontinuation of Denosumab as a Potential Cause of Generalized External Cervical Root Resorption: A Case Report.

Generalized occurrence of external root resorption in an adult patient is a rare finding. This case report describes external cervical root resorption extensively affecting the dentition that may be associated with the use and subsequent cessation of denosumab for the treatment of osteoporosis.

Trephination-based, guided surgical implant placement: A clinical study.

STATEMENT OF PROBLEM: Conventional guided implant surgery promises clinical success through implant placement accuracy; however, it requires multiple drills along with surgical sleeves and sleeve adapters for the horizontal and vertical control of osteotomy drills. This results in cumbersome surgery, problems with patients having limited mouth opening, and restriction to specific drill or implant manufacturers. A protocol for using trephination drills to simplify guided surgery and accommodate multiple implant systems is introduced. PURPOSE: The purpose of this clinical study was to evaluate the accuracy of implant placement using this novel guided trephine drill protocol with and without a surgical sleeve. MATERIAL AND METHODS: Intraoral scanning and preoperative cone beam computed tomography (CBCT) scans were used for implant treatment planning. Surgical guides were fabricated using stereolithography. Implant surgery was performed using the guided trephination protocol with and without a surgical sleeve. Postoperative CBCT scans were used to measure the implant placement deviations rather than the implant planning position. Surgical placement time and patient satisfaction were also documented. One-tailed t test and F-test (P=.01) were used to determine statistical significance. RESULTS: Thirty-five implants in 17 participants were included in this study. With a surgical sleeve, implant positional deviations were 0.51 ±0.13 mm vertically, 0.32 ±0.10 mm facially, 0.11 ±0.11 mm lingually, and 0.38 ±0.13 mm mesially. Without a surgical sleeve, implant positional deviations were 0.58 ±0.27 mm vertically, 0.3 ±0.14 mm facially, 0.39 ±0.16 mm lingually, and 0.41 ±0.12 mm mesially. No statistically significant difference was found between the 2 protocols (P>.01), except that the sleeve group had greater vertical control precision (F-test, P=.006), reduced placement time, and the time variation was reduced (t test, P=.003; F-test, P<.001). CONCLUSIONS: This trephination-based, guided implant surgery protocol produces accurate surgical guides that permit guided surgery in limited vertical access and with the same guided surgery protocol for multiple implant systems. Guided sleeves, although not always necessary, improve depth control and reduce surgical time in implant placement.

Do Implant Surgical Guides Allow an Adequate Zone of Keratinized Tissue for Flapless Surgery?

PURPOSE: A major advantage of guided implant surgery using 3-dimensionally printed guides is the ability to perform accurate flapless surgery. A drawback of a flapless technique is the inability to manipulate soft tissue to ensure sufficient gingiva around the implant. The purpose of this study was to determine how often flapless surgery using surgical guides results in less than 2 mm of keratinized tissue surrounding the implant. MATERIALS AND METHODS: This retrospective analysis included 27 maxillary and 27 mandibular implant sites that underwent treatment planning for implant-guided surgery using 3Shape Implant Studio (3Shape, Copenhagen, Denmark). Intraoral scan images were used to measure the width of the keratinized tissue on the buccal aspect of each implant site in both arches and the lingual aspect in the mandibular arch. Three examiners measured the amount of buccal and lingual keratinized tissue in millimeters at each implant site. Analysis of variance (P < .05) and correlation coefficients were used to determine statistically significant differences in keratinized tissue among sites. RESULTS: No statistically significant difference was found either between the widths of buccal keratinized tissue in the maxillary anterior (4.06 ± 1.42 mm) and posterior (4.93 ± 2.54 mm) areas (P = .293) or between the amounts of buccal and lingual keratinized tissue in the mandible (P = .995). The keratinized tissue width in the maxillary buccal area was significantly different (4.48 ± 2.04 mm) from that in the mandibular posterior buccal (1.98 ± 1.41 mm) and lingual (1.98 ± 1.23 mm) areas (P < .001). Over 77% of maxillary implant sites had greater than 3 mm of gingiva, and just over 20% had sufficient gingiva in the mandible. CONCLUSIONS: Adequate keratinized tissue was found in most of the planned maxillary implant sites, whereas most of the mandibular posterior implant sites had inadequate keratinized tissue. Therefore, elevation of a flap to preserve and reposition existing keratinized tissue around implants should be considered when planning to use tooth-borne surgical guides in the posterior mandible.

In Vivo Tooth-Supported Implant Surgical Guides Fabricated With Desktop Stereolithographic Printers: Fully Guided Surgery Is More Accurate Than Partially Guided Surgery.

PURPOSE: Desktop stereolithographic printers combined with intraoral scanning and implant planning software promise precise and cost-effective guided implant surgery. The purpose of the present study was to determine the overall range of accuracy of tooth-supported guided implant surgery using desktop printed stereolithographic guides. MATERIALS AND METHODS: A cross-sectional study comparing fully and partially guided implant surgery was conducted. Preoperative cone beam computed tomography (CBCT) and intraoral scans were used to plan the implant sites. Surgical guides were then fabricated using a desktop stereolithographic 3-dimensional printer. Postoperative CBCT was used to evaluate the accuracy of placement. Deviations from the planned positions were used as the primary outcome variables. The planning software used, implant systems, and anterior/posterior positions were the secondary outcome variables. The differences between the planned and actual implant positions in the mesial, distal, buccal, and lingual dimensions and buccolingual angulations were determined, and the accuracy was compared statistically using the 1-tail F-test (P = .01), box plots, and 95% confidence intervals for the mean. RESULTS: Sixteen partially edentulous patients requiring placement of 31 implants were included in the present study. The implant deviations from the planned positions for mesial, distal, buccal, and lingual dimensions and buccolingual angulations with the fully guided protocol (n = 20) were 0.17 ± 0.78 mm, 0.44 ± 0.78 mm, 0.23 ± 1.08 mm, -0.22 ± 1.44 mm, and -0.32° ± 2.36°, respectively. The corresponding implant deviations for the partially guided protocol (n = 11) were 0.33 ± 1.38 mm, -0.03 ± 1.59 mm, 0.62 ± 1.15 mm, -0.27 ± 1.61 mm, and 0.59° ± 6.83°. The difference between the variances for fully and partially guided surgery for the distal and angulation dimensions was statistically significant (P = .006 and P < .001, respectively). No statistically significant difference was found between the software programs. Anterior implants had less variation in deviation than posterior implants. CONCLUSIONS: Fully guided implant surgery is more accurate than partially guided implant surgery. Implant positional deviation is influenced by implant location but not implant systems or software. If possible, clinicians should use guided surgery protocols that allow placement of implants through a surgical guide.

Helicopter Mountain Rescue in Slovenia from 2011 to 2015.

INTRODUCTION: The popularity of adventure recreation in wilderness areas across the world continues to increase. Nevertheless, the risk of injury and illness remains significant. The purpose of this study is to analyze the mountain rescue operations performed in Slovenia between 2011 and 2015. METHODS: This retrospective study reports mountain rescue operations documented by the Slovenian National Mountain Rescue Association. The annual number of ground-based and helicopter-based rescues were identified and compared. For 2015, the indication for rescue and the severity of injury were also analyzed, specifically for interventions requiring the use of a helicopter. RESULTS: From 2011 through 2015, the number of rescues remained consistent with an annual average of 413 (SD ±15; range, 393-434) rescues. However, the percentage of ground-based rescues varied significantly year by year (P=0.016), with highest rate in 2014 (68%) and the lowest in 2015 (56%). In 2015, 434 mountain rescue operations were reported in Slovenia. Injury accounted for 44%, illness for 10%, and fatality for 9% of the rescues. In 37%, no illness or injury was reported. Helicopter rescue was used in 190 (44%) of all interventions. Among the 190 helicopter rescues, 49% of patients had nonfatal injuries, 29% required no medical treatment, 15% had illness, and 7% had fatal injuries. CONCLUSIONS: A significant number of mountain rescue operations were conducted in Slovenia from 2011 through 2015. Most of these were needed for injured, ill, or deceased persons. A notable number of rescues in 2015 required a helicopter.

Burnout, depression and suicidal ideation in dental and dental hygiene students.

INTRODUCTION: The aim of this study was to assess the relationship between burnout, depressive symptoms and suicidal ideation in dental and dental hygiene students and to evaluate the influence of gender, programme type and year of study. SUBJECTS AND METHODS: Third- and fourth-year dental (DS) and first- and second-year hygiene students (DHS) completed the Patient Health Questionnaire (PHQ-9) and an abbreviated Maslach Burnout Inventory online as measures of depressive symptoms/suicidality and burnout, respectively. The statistical analyses included summary statistics and tests for intergroup comparisons (chi-square) to evaluate the influence of gender, programme type (DHS or DS) and year of study. Correlations between depression, suicidality and burnout were also conducted. RESULTS: A total of 32 dental hygiene and 119 dental students participated. 40% of the dental and 38% of the hygiene students met criteria for burnout. No differences were found between years or between programmes. Nine per cent of both dental and hygiene students were above the cut-off for moderate depressive symptoms, but there were no statistical differences between the third- and fourth-year dental and the first- and second-year hygiene students. Six per cent of the dental and 9% of the dental hygiene students were above the cut-off for clinically significant suicidal ideation, but there were no statistical differences between dental and hygiene students. There were no differences noted in the dental students based on gender for any of the measures. Depression was significantly associated with all three subscales of burnout. Suicidal ideation was only significantly related to the lack of personal accomplishment subscale of burnout. DISCUSSION: These findings suggest the need for introducing preventive measures for such affective states in dental and dental hygiene training programmes.