目的：本邦では，上顎無歯顎症例において，4本のインプラント体を埋入し，即時荷重を行うAll-on-4 conceptに基づく治療に関する報告は少ない．本研究の目的は，上顎にAll-on-4 conceptに基づく治療を行い，上部補綴装置装着後3年以上経過した症例を評価することである．

材料および方法：対象はAll-on-4 conceptに基づき咬合再構成を行った150例，662本である．1症例あたりの埋入本数，インプラント体の種類，長さ，埋入時の初期固定値，埋入部位，既往歴，喫煙習慣の有無について調査し，インプラント体の脱落に関与する要因を検討した．

結果：インプラント体の脱落は17本に認められ，残存率は97.4％であった．埋入部位別では，左側後方傾斜埋入部位は右側前方埋入部位と比較し，有意に低い残存率であった．喫煙者は非喫煙者と比較し，有意に低い残存率であった．

結論：All-on-4 conceptに基づいた治療は高いインプラント残存率を示し，臼歯部の残存歯槽骨量の少ない上顎無歯顎症例に対して，有効な治療方法の一つであることが示唆された．

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Thanks to recent developments of digital plate and laser imaging technologies, quality of flexography has been improved significantly. However, appropriate control of unique behavior and characteristics of flexo printing remain to be a major challenge in achieving superior print results. One of the important aspects of flexo process that determines final print quality is to control the ink behavior in highlight and shadow areas. Recent development of special screening technologies, such as " Screens", is to achieve better transfer and even distribution of ink at shadow and solid areas, and "Perfect Highlight" screening which helps to prevent undesirable highlight breaks and excessive dot from gaining drastically improve visual print quality of shadow and highlight area. I believe implementation of these screening technologies can be a significant contribution for development of new level of flexo printing value in Japan.

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本研究の目的は，上部構造破損の破損と終日の咀嚼筋筋活動について携帯型筋電計を使用して，その関連を明らかにすることである．

岩手医科大学附属病院歯科医療センター口腔インプラント科を受診している患者で，上部構造装着後に前装部材料の破損が認められた10名を被験者とした．今回，上部構造の破損によって Catastrophic failure （CF 群）と Control （CO 群）の２群に分けて各々の筋活動動態の解析を行った．実験使用した携帯型筋電計は本体と電極で構成されている．筋電計は終日（約24 時間）咬筋に装着し，日常生活を阻害することなく測定が可能である．得られたデータはパーソナルコンピュータ上で分析を行い，行動記録を対応させた．ブラキシズムの識別閾値は過去の研究から値を設定した．

全被験者に閾値を越えたブラキシズム様イベントが観察された． CF 群はCO 群と比較し覚醒時と睡眠時の非機能運動時における筋活動量が有意に高い値を示した（p<0.05 Mann-Whitney U-test）．また，機能運動時における筋活動量に有意差はみとめられなかった．

本研究の結果から，インプラント上部構造の破損と筋活動量に関連があることが示唆された．

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Once a software product has been released, a large number of software products may be derived from an original single product. Management and maintenance of product variants are important, but those are hardly cared because developers do not make efforts for the further maintainability in the initial phase of software development. However, history of products would be lost in typical cases and developers have only source code of products in the worst case. In this paper, we approximate the evolution history of software products using source code of them. Our key idea is that two successive products are the most similar pair of products in evolution history, and have many similar source files. We did an experiment to compare the analysis result with actual evolution history. The result shows 78% (on average) of edges in the extracted trees are consistent with the actual evolution history of the products.

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When debugging bugs, programmers often prepare test cases to reproduce buggy behaviours. However, for concurrent programs, test cases alone are typically insufficient to reproduce buggy behaviours, due to the nondeterminism of multi-threaded executions. In literature, various approaches have been proposed to reproduce buggy behaviours for concurrency bugs deterministically, but to the best of our knowledge, they are still limited. In particular, we have recognized three debugging scenarios from programming practice, but existing approaches can handle only one of the scenarios. In this paper, we propose a novel approach, called SPDebugger, that provides finer-grained thread controlling over test cases, programs under test, and even third party library code, to reproduce the predesigned thread execution schedule. The evaluation shows that SPDebugger handles more debugging scenarios than the state-of-the-art tool, called IMUnit, with similar human effort.

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インプラント治療において，歯槽骨量が少ない場合は骨造成を併用してインプラントを埋入する方法が多く取り入れられてきている．しかし，大きな骨造成を行なうことにより患者および術者への負担も大きくならざるを得ないという欠点があった． そこで，ショートインプラントを適正な位置に埋入することにより，低侵襲で埋入を行ない，患者への負担を軽減するように試みられてきた． しかし，欠損部の大きい全顎治療等でインプラントの埋入本数が増えた場合は，技工側は上部構造の補綴物製作にあたり鋳造物が大きく鑞着部分が多くなり，高度な技工技術が必要になる．さらに多くの貴金属の使用によりコストの増加がともない，患者側の経済的負担にもなっていた． プロセラインプラントブリッジの最大の特長はCAD/CAM システムによって製作され，従来の鋳造物と比較し，チタンブロックからの削り出しのため，変形のリスクがないことである．フレーム自身がアパットメントと一体構造，高強度，作製過程の簡略化と低コストである利点がある． 本論文においてショートインプラントとプロセラインプラントブリッジを用いたインプラント治療の結果，精度が高く一定の審美性のある上部構造を持ったインプラント補綴治療ができ，本治療方法は以下のような特長をあわせて有している． 1．ショートインプラントによる患者，術者への負担軽減 2．プロセラインプラントブリッジによる製作過程の簡略化と低コスト化 これらの結果から今後のインプラント処置の選択肢の1 つとなりうることが示唆された．

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When a user listens to a song for the first time, what musical factors (e.g., melody, tempo, and lyrics) influence the user's decision to like or dislike the song? An answer to this question would enable researchers to more deeply understand how people interact with music. Thus, in this paper, we report the results of an online survey involving 302 participants to investigate the influence of 10 musical factors. We also evaluate howa user's personal characteristics (i.e., personality traits and musical sophistication) relate to the importance of each factor for the user. Moreover, we propose and evaluate three factor-based functions that would enable more effectively browsing songs on a music streaming service. The user survey results provide several reusable insights, including the following: (1) for most participants, the melody and singing voice are considered important factors in judging whether they like a song on first listen; (2) personal characteristics do influence the important factors (e.g., participants who have high openness and are sensitive to beat deviations emphasize melody); and (3) the proposed functions each have a certain level of demand because they enable users to easily find music that fits their tastes. We have released part of the survey results as publicly available data so that other researchers can reproduce the results and analyze the data from their own viewpoints.

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ＣＧアニメーションの中でもダンス映像をよりリアルで質の高いものにするため、ダンスらしさを表現する動作を解明する。今回は現代的リズムダンスのひとつであるストリートダンスに着目してストリートダンスらしさを明らかにした。ストリートダンスは音楽にあわせて身体を揺するダンスであり、「ノリ」感覚が重要である。初心者と上級者の動きを比べると、上級者はビートの前後で動きに時間的な変化（加速・減速・遅延）をつけること、体幹運動（手足を動かすのではなく、身体の中心部を動かして手足を連動させる）をすること、が特徴的であった。そこで、ＣＧキャラクタでこれらの動きを表現し、「ノッている」感覚を評価する実験を行った。結果、加速・減速運動と体幹運動は「ノリ」感覚に影響があること、この影響度は音楽のビートの強さによって異なってくること、などが確かめられた。

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It is necessary to establish a methodology of developing multimodal interactive systems as the spread of various input and output devices. Previous MMI (MultiModal Interaction) description language used a state transition model for defining interaction and that has low maintainability and extensibility. In this paper, we design and implement a new MMI description language named MrailsScript from the software engineering point of view. MrailsScript consists of the datamodel definition that can be inherited from semantic web class definition, and the annotations of interaction task and dialogue initiative. By expanding the existing web application development framework, our Mrails framework can automatically generate prototype codes of MMI application which is based on MVC (Model-View-Controller) model. We also developed a helper application of MMI system, MrailsBuilder, which assists coding of MrailsScript and realizes multilingual capability of the target MMI system.

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A sense of presence and unity is important in music. It has also been empirically pointed out that there is an emotion similar to a feeling of elation called “groove” in music listening and performance situations. In previous studies, “groove” has often been examined from the perspective of tempo and timing deviation from the beat, especially from the listener’s point of view. In this paper, we constructed a “model of the process of forming a sense of groove by players during cooperative performances of multiple players” through questionnaires and interviews, with the aim of systematically organizing the causes, factors, and elements that form the sense of groove. This model is expected to clarify the position of previous studies and help in both basic and applied research.

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Here, we describe the provision of an implant-supported prosthesis in a patient with impacted teeth in the maxilla, which complicated implant placement and necessitated utilization of the extraction sockets of previously impacted teeth and residual submerged roots. The patient was a 63-year-old man who visited our clinic with the chief complaint of difficulty in mastication. Numerous residual roots were observed in the maxilla, and radiographic imaging revealed that the residual roots of teeth #13 and #16 were fully impacted. The patient complained of a strong sensation of a foreign body in the area of a denture support overlying these residual roots. Therefore, the impacted teeth were extracted, 5 implants placed, and a temporary prosthesis provided. Given the necessity of placing the implant through the extraction socket of the impacted canine (#13), favorable initial stability was achieved using a long (>20 mm) implant. Moreover, autogenous bone obtained by osteotomy was grafted onto the extracted impacted tooth socket. The clinical condition was stable at approximately 1 year after implant placement and so the final prosthesis was delivered, with periodic check-ups being performed every 3 months thereafter. After 4 years, the patient has reported no symptoms. Clinically, there are no signs of inflammation, and the postoperative condition is deemed to be very favorable.

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これまで，構造化データ表現とそのためのスキーマ定義言語，パーザ生成系のための構文ルール記述などで内 部DSL を活用してきた．内部DSL を使うことによって，簡潔で強力な記述が可能になる．本稿では，これらの 経験を踏まえ，内部DSL をシステム開発に活用する上でのポイントについて検討する．

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Purpose: We examined safety issues related to the presence of various metallic dental materials in magnetic resonance (MR) imaging at 7 tesla.
Methods: A 7T MR imaging scanner was used to examine 18 kinds of materials, including 8 metals used in dental restorations, 6 osseointegrated dental implants, 2 abutments for dental implants, and 2 magnetic attachment keepers. We assessed translational attraction forces between the static magnetic field and materials via deflection angles read on a tailor-made instrument and compared with those at 3T. Heating effects from radiofrequency during image acquisitions using 6 different sequences were examined by measuring associated temperature changes in agarose-gel phantoms with a fiber-optic thermometer.
Results: Deflection angles of the metallic dental materials were significantly larger at 7T than 3T. Among full metal crowns (FMCs), deflection angles were 18.0° for cobalt-chromium (Co-Cr) alloys, 13.5° for nickel-chromium (Ni-Cr) alloys, and 0° for other materials. Deflection angles of the dental implants and abutments were minimal, ranging from 5.0 to 6.5°, whereas the magnetic attachment keepers were strongly attracted to the field, having deflection angles of 90° or more. Increases in temperature of the FMCs were significant but less than 1°C in every sequence. The dental implant of 50-mm length showed significant but mild temperature increases (up to 1.5°C) when compared with other dental implants and abutments, particularly on sequences with high specific absorption rate values.
Conclusion: Although most metallic dental materials showed no apparent translational attraction or heating at 7T, substantial attraction forces on the magnetic attachment keepers suggested potential risks to patients and research participants undergoing MR imaging examinations.

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Nihon University School of Dentistry Dental Hospital adopted program 1 and program 2 as a dental training program in 2013. All dental trainees are given training by cooperating facilities determined by matching a group at program 1 or management-type facilities, program 2. Every year, they have implant placement training with a jaw bone model at the end of the program. The aim of this study is an investigation of their training environment, or consciousness about implant therapeutics.
Dental trainees have certain opportunities to experience implant treatments at either the cooperating or management-type facilities. Moreover, since they have therapeutic experience during the programs, implant placement training made them fully understood the steps of implant therapy.

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インプラントの上部構造の作製法には支台歯形成してセメンティングする方法と，スクリューリテイニング式とがある．補綴物装着後の補綴物の補修やメインテナンスを考慮すると，スクリューリテイニング式の方が有利である．特に少数のインプラントで多数歯を修復する場合には特に有効である．ところが，従来の鋳造法でスクリューリテイニング式の補綴物を作製する際には，ロウ着の手間がかかる上，適合や強度に問題があった．
今世紀から，Nobel Biocare 社のPIB（Procera Implant Bridge）に代表される，CAD/CAM 方式による，Computer numeric controlled（CNC）-milled frameworks，つまりコンピュータ制御の削りだしフレームによる上部構造の作製法が長期的に臨床応用されるようになった．2009年になると，PIB（Nobel Biocare 社，Sweden）だけではなくI-Bridge（Bio-Main 社，Sweden）もCNC-milled frameworks　として臨床応用されるようになった．
今回，PIB やI-Bridge でインプラントの上部構造を作製した症例486例について補綴物装着後，約10年から半年経過した症例について経過観察した．そこで，CNC-milled frameworks の作製法やインプラントの補綴を成功させる方法についてご紹介し，この方法で補綴を利用したインプラントの臨床的な生存率について検証したい．使用したインプラントはすべてNobel Biocare 社製で，本数は1,563本であった．予後不良で撤去したインプラントは5本で，臨床的なインプラントの生存率は約99.93％であった．比較的良好な安定性が得られていると思われるが，これはこの方法の適合精度が良好なことと，フレームの強度が十分あることによると思われる．

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