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Objectives. Although digital technology has been widely integrated into dental education, there is limited literature investigating the extent of the integration of computer-aided design and computer-aided manufacturing (CAD-CAM) for removable systems in the dental curriculum. The purpose of this study was to assess the current implementation of CAD-CAM complete and partial dentures in predoctoral (PP) and advanced graduate prosthodontic (AGP) education in US dental schools. The study also aimed to identify potential barriers to its implementation in the dental curriculum. Methods. An online survey with 15 questions was created using online survey software. The survey was distributed to the directors of predoctoral prosthodontics in 56 schools and advanced graduate programs of prosthodontics in 52 schools listed in the 2018–19 American Dental Education Association (ADEA) Directory. Results. The percentage of programs (PP and AGP) implementing CAD-CAM complete dentures (CAD-CAM CDs) and CAD-CAM removable partial dentures (CAD-CAM RPDs) in their didactic, preclinical, and clinical curricula was recorded. CAD-CAM CDs are taught in didactic courses in 54.2% of PP and 65.2% of AGP. However, CAD-CAM RPDs are only taught in 37.5% of PP and 47.8% of AGP. Programs are largely limited by a lack of funds, resources, time, and faculty members. Conclusion. While digital technologies have indeed become more prevalent in dental education, many institutions face barriers to implementation. More research must be conducted in order to support the continued incorporation of digital technologies into dental education. [ABSTRACT FROM AUTHOR]

Various techniques have been applied to the fabrication of duplicate dentures. In this new method, after scanning the cameo and intaglio surfaces of the complete denture using an intraoral scanner, the two images were superimposed on the interocclusal image. The linear gap between cameo and intaglio surfaces was filled using free downloadable CAD software. The superimposed image was subsequently used as data for fabricating the duplicate complete denture with a 3D printer. Using the intraoral scanner, duplication of complete dentures could be performed without needing any complicated processes, laboratory scanners, or advanced CAD software. [ABSTRACT FROM AUTHOR]

Adequate oral status and functional assessments are important for dysphagia rehabilitation in acute care inpatient settings, especially to establish individualised oral intake. However, the association between food intake levels and oral function has not been elucidated in acute care inpatients. This cross‐sectional study clarified the association between oral intake levels and the oral status/function of patients with dysphagia admitted to acute care settings. Admitted patients aged ≥40 years (n = 459; men: 288; mean age: 70.8 ± 12.0) examined at the Department of Dysphagia Rehabilitation at the Iwate Medical University Hospital from April 2007 to March 2014 were included. The oral health status was evaluated by the tongue coating, oral dryness severity, plaque control, posterior occlusal support and a repetitive saliva swallowing test (RSST). Dysphagia severity was determined from the Dysphagia Severity Scale. Oral intake levels were evaluated using the Functional Oral Intake Scale (FOIS) at the time of the initial dental examination (FOIS‐I), and they were re‐evaluated after the revision of levels according to the participants' general condition and oral health status (FOIS‐R). Divergence between FOIS‐I and FOIS‐R was noted in >40% patients. Multiple regression analysis showed significant associations between FOIS‐R and consciousness level, activities of daily living, tongue coating, RSST and posterior occlusal support. Patients with dysphagia in acute care settings require detailed assessments of their oral status and function, including swallowing, to determine the most suitable feeding methods and dental interventions to improve oral intake levels. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of wearing complete dentures on pharyngeal shape for swallowing in edentulous older people.Background: In the absence of complete dentures, edentulous older people often lose the occlusal support necessary to position the mandible, which leads to an anterosuperior shift of the mandible during swallowing. This may result in pharyngeal shape changes effecting swallowing function in older people. However, the details of this phenomenon are currently unclear.Materials and Methods: Participants were 17 older edentulous volunteers. Cone-beam computed tomography imaging was performed with the participant in the seated position and wearing (i) both maxillary and mandibular dentures, (ii) maxillary dentures only and (iii) no dentures. During imaging, participants were instructed to keep their mouth closed to the mandibular position determined in advance during swallowing for each denture-wearing condition. The volume, height and average cross-sectional area of the velopharynx and oropharynx were measured, and the positions of the epiglottis and mandible were recorded.Results: While the vertical height of the oral cavity and pharynx significantly decreased, the volume and average cross-sectional area of the oropharynx significantly increased when dentures were not worn (p < 0.01). The absence of dentures caused an anterosuperior shift of the mandible when swallowing and drew the epiglottis forward, resulting in expansion of the oropharynx where the tongue base forms the anterior wall.Conclusion: The absence of dentures results in anatomical changes in oropharyngeal shape that may exacerbate the pharyngeal expansion caused by ageing and reduce the swallowing reserve. [ABSTRACT FROM AUTHOR]

Collagen containing bone morphogenetic protein‐2 (BMP‐2) expression vector, which is called "gene‐activated matrix," promotes bone regeneration when transplanted to the bone defect. We speculated that hydroxyapatite fiber (HF) would be an ideal matrix for "gene‐activated matrix" especially for bone regeneration, because it is oseteoconductive and has high affinity to DNA. The purpose of this study is to clarify whether HF containing BMP‐2 expression vector induces ectopic bone formation. We prepared HF containing 0, 10, 50, and 100 μg BMP‐2 expression vector. Wistar male rats (8 weeks) were used and each rat received two HF implants in the left and right dorsal muscle. The rats were sacrificed 4, 8, and 12 weeks after the operation, and implants were analyzed radiographically by softex, dual‐energy X‐ray absorptiometry, and they were histologically examined. At 4 weeks, HF containing 50 or 100 μg BMP‐2 expression vector showed high bone mineral contents and large radiopaque volume compared to the other implants. At 8 and 12 weeks, HF containing 50 μg BMP‐2 expression vector exerted the highest values in the radiographic analyses. Bonelike tissue was histologically observed in HF containing 50 and 100 μg BMP‐2 expression vector groups but not detected in the other implants. The present results suggest that HF is potential as a matrix for "gene‐activated matrix" for bone tissue engineering. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [ABSTRACT FROM AUTHOR]

Background: Resonance frequency analysis (RFA) is applied to evaluate implant stability, and the clinical relevance of this application is accepted. However, a discrepancy between resonance frequency (RF) and other parameters of implant stability such as implant insertion torque and bone mineral density at the insertion site has been reported. In addition, the relation between RF and histological implant–bone contact has not been well documented. Purpose: To explain this discrepancy and to clarify the relation between RF and histological implant–bone contact, we conducted the present study. Materials and methods: A hydroxyapatite-coated implant, 4 mm diameter and 10 mm length, was used. We placed the implant in a small plastic box vertically and fixed the implant in the box with small screws at different height positions. An ‘Osstell’ transducer was mounted on the implant and RF was measured with or without loosening the screws. Twenty-four implants were placed in the tibiae of four mini-pigs. The animals were sacrificed 1, 2 and 4 weeks after the placement, and the RF of each implant was measured. Ground sections were prepared and implant–bone contact was histomophometrically measured. Results: Loosening the screw at the neck region of the implant remarkably decreased RF compared with the screws of the other regions. Correlation between RF and implant–bone contact, which was measured all around the implant, was not significant ( r=0.221, P=0.299). However, the correlation coefficient increased to ‘0.361’ when implant–bone contact was measured at the neck of the implant ( P=0.0835), although these two parameters were not statistically correlated. Conclusions: Although RF did not correlate with histological implant–bone contact, the present results demonstrated that a connection between the implant and bone at the neck region of the implant affects RF the most effectively, further suggesting the superiority of RFA in the process of implant treatment and the follow-up. The present results could explain the discrepancy between RFA and other parameters of implant stability. [ABSTRACT FROM AUTHOR]

Objective: Enamel matrix derivative (EMD) has been clinically used to promote periodontal tissue regeneration. The purpose of the present study is to clarify EMD affects on osteoblastic cells and bone regeneration. Materials and Methods: Mouse osteoblastic cells (ST2 cells and KUSA/A1 cells) are used in culture experiments. After cells were treated with EMD, cell growth was evaluated with DNA measurement, 5-bromo-2′-deoxyurydine (BrdU) incorporation assay. Measurement of alkaline phosphatase (ALP) activity and mineralized-nodule (MN) formation, Northern blotting analysis and zymography are also performed. In addition, EMD was applied to a rat skull defect and the defect was radiographically and histologically evaluated 2 weeks after the application. Results: EMD did not stimulate ST2 cell growth; however, it enhanced KUSA/A1 cell proliferation. Although EMD stimulated ALP activity in both the cells, ALP activity in KUSA/A1 cells was affected to a much greater degree. Corresponding to the increase in ALP activity, MN formation in KUSA/A1 cells was enhanced by EMD. EMD stimulated osteoblastic phenotype expression of KUSA/A1 cells such as type I collagen, osteopontin, transforming growth factor beta 1 and osteocalcin. EMD treatment also stimulated matrix metalloproteinase production in KUSA/A1 cells. Although the effects of EMD on osteoblastic cells depend on cell type, the overall effect of EMD on osteoblastic cells is stimulatory rather than inhibitory. Finally, EMD application to a rat skull defect accelerated new bone formation. Conclusion: These results indicate that EMD affects osteoblastic cells and has potential as a therapeutic material for bone healing. [ABSTRACT FROM AUTHOR]

Sinus floor elevation is often applied to the molar region of the atrophic maxilla to increase in bone mass between the alveolar crest and the sinus floor. Although autogenous bone graft is, so far, gold standard, limitations of donor site bone volume and post‐operative morbidity could be disadvantages. Thus, artificially synthesized bone substitutes, hydroxyapatite (HA) and tricalcium‐phosphate (TCP), might be considerably useful materials compared to the autogenous bone. [ABSTRACT FROM AUTHOR]

Background: Peri‐implantitis is one of the most frequent biological complication in implant therapy. There have been many reports concerning peri‐implantitis and its treatment in recent years. However, most of those are related to symptomatic treatment, and the curable method that can recover bone loss has not been established yet. Aim/Hypothesis: The purpose of this study is to evaluate the treatment effects of combination of mechanical debridement with autogenous bone graft. Material and Methods: We have treated five patients who had severe peri‐implantitis. All patients were treated by one surgeon. We performed mechanical debridement using titanium micro brush and simultaneous autogenous bone graft. Before the surgery, abutment and prosthesis were removed. Contaminated tissue around the implant was removed, and the roughened surface of the implant was mechanically polished with a titanium microbrush. Subsequently, autologenous bone taken from the mandibular branch was transplanted and covered with a collagen membrane. All the prosthesis were placed after six months healing period and followed up every three months. Results: In all the cases, soft tissue healing was pretty good. There are no unfavorable findings, including the post‐operative infection and discomforts. The x‐rays analyses revealed the recovery of the peri‐implant bone loss. So far, patients have shown good prognosis without pain, swelling, or bone re‐resorption. Conclusions and Clinical Implications: The titanium micro wire brush could reach to microscopic structure like micro threads on the implant body, indicating the usefulness of mechanical cleaning. As a result, exposed titanium fresh surface enables the re‐osseointegration. Those findings suggest that the combination of titanium wire brush debridement and autogenous bone graft is effective on peri‐implantitis. [ABSTRACT FROM AUTHOR]