牙齿矫正后要怎样护理？

第一篇：牙齿矫正后要怎样护理？

牙齿矫正后要怎样护理？

现在我们越来越多的会选择牙齿矫正手术，因为牙齿矫正能帮助我们尽量修复好牙齿。但是，是不是每个人都知道牙齿矫正后的护理工作呢？下面上海仁爱医院口腔专家针对此做出的相关介绍，希望对大家有所帮助。

口腔专家介绍说，美容冠牙齿美容技术是一种新兴牙齿美容技术，在传统烤瓷牙的基础上强调牙齿的美容效果，对错位牙、畸形牙的临床冠部分施以专业手段，最后用美容冠加以修复。具有美牙不拔牙、无痛苦、时间短、牙齿坚固、多年后牙龈不会出现黑线等优点，从而达到终生有保障的美牙效果。

牙齿矫正后要怎样护理？

1、注意饮食：

固定矫治器是用教固剂将矫治器粘结到牙齿上，正畸期间尽量避免食用过硬的食物，以免损坏矫治器零件，使矫治力量中断，延长疗程。此外，为了防止蛀牙也应该少食用甜食。

2、戴用保持器：

牙合畸形矫正后，不要以为就没事了，为了保持好正畸的效果，要认真戴用一段时间的保持器，定期复诊。

3、注意口腔卫生：

戴用活动矫治器或固定矫治器都要保持口腔卫生，尤其是固定矫治器，由于矫治器粘固在牙齿上，不能取下刷牙，且矫治器周围极易存留食物残渣，造成细菌大量繁殖。因此，求美者要养成饭后刷牙的习惯，每次刷牙不少于5分钟，采用横竖交替法，使用含氟牙膏，活动矫治器也要用牙膏刷洗干净。

4、定期复诊：

牙齿正畸治疗需要不断加力调整，所以需要求美者按照医嘱定期到医院复诊，调整矫治力度达到最佳的矫治效果。

温馨提醒：以上是关于“牙齿矫正后要怎样护理”的相关介绍，希望对您有所帮助，如果您还有什么问题或者有什么不明白的地方，可以点击在线咨询，专家会根据您的具体情况进行具体的分析，详细客观的解答您的所有问题。

第二篇：航海英语50期矫正后 Microsoft Word 文档

三副航海英语机考50期 903 矫正后答案(2011-04-21 12:46:55)

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分类： 考试与补考重修

三副 航海英语 机考 50期 903 矫正后 答案 教育

50期 903英语机考题目汇编

1,[2286]Some of these shoals have been disproved and are not charted．Nevertheless mariners should ______ with particular caution in this area． A.go B.proceed C.move D.remove KEY: B 2,[136]Information on the operating times and characteristics of foreign radiobeacons can be found in which publication? A.List of Lights B.Coast Pilot C.Sailing Directions D.List of Radiobeacons KEY: A 3[247]A red triangular daymark marks ______.A.the centerline of a navigable channel B.the starboard side of a channel C.a prominent object of navigational interest that has no lateral significance D.an area of a channel where passing another vessel is permitted KEY: B 4[293]What information is found in the chart title? A.Date of the first edition B.Date of the edition and，if applicable，the revision C.Information on the sounding datum D.Information on which IALA buoyage system applies KEY: C 5[284]The maximum difference between mean time and apparent time is ______.A.equal to the longitude expressed in time units B.about 16 minutes C.the difference between the GHA of mean sun and the first point of Aries D.15°of arc KEY: B 6[279]The chart of a beach area shows a very flat slope to the underwater beach bottom.What type of breakers can be expected when trying to land a boat on this beach? A.Surging B.Spilling C.Plunging D.Converging KEY: B 7,the broken magenta lines starting at Mountank point and running generally ENE to Block Island indicate ___A_____ A recommended tracks to Block Island B a submerged cable area C a military exercise area D demarcation [ˌdi:mɑ:ˌkeɪʃən] 分界线lines for application of the COLREGS 8 navigate with _D___ small fishing boats are within 0.8miles of me A carefulil B skill C concern D caution 9[469]Mariners are FIRST warned of serious defects or important changes to aids to navigation by means of ______.A.marine broadcast Notice to Mariners B.Weekly Notices to Mariners C.corrected editions of charts D.Light Lists KEY: A 10[353]All events relating to the voyage，such as ship's position，speed and details of the weather，are recorded in ______.同原题库2246 A.Logbook B.Bell Book C.Oil Record Book D.Compass Error Book KEY: A所有与航次有关的事件，诸如船位，航速和气象的详细资料都被记录在航海日记中。11[377]Prior to burning or welding on a fuel tank on a ship, regulations require that an inspection be made.An entry in the unofficial logbook is required if this inspection is made by ______.A.a marine chemist B.the Officer in Charge, Marine Inspection C.the Master or person in charge of the ship D.the National Fire Protection Association KEY: C在船上燃油舱烧焊之前，规则要求进行检查。假如检查由船长或船舶负责的人员完成，则要求记录非正式航海日志 12[622]I have ______ damage below water line.同原题库0327 A.large B.big C.important D.major KEY: D我船水线下有较大的损坏。

13___D__ the torn bags of castor seeds you mentioned we have already replaced them by new ones.A regard B regards C regarded D regarding 14who checks the bridge clock for accuracy each day? B A third officer B second officer C chief officer D assistant officer 15 Which signal of the follwings is not provided with onboard lifeboat? A.Rocket parachute signals B.Buoyant smoke signals C.Hand flare signals D.Self-igniting signals 答案：D下列哪种信号在救生艇上不配备？自动点火信号 16[5405]A qualified deck officer should be ______ the watch． A.in charge of B.arranged C.decided to D.the depth of KEY: A 17.Emergency compressed air breathing escape sets onboard, shall have a duration of service no less than _____.A.20 minutes B.15 minutes C.10 minutes D.5 minutes 答案：B船上应急压缩空气呼吸逃生装置使用时间不少于15分钟

18114.According to SOLAS the breathing air apparatus that must be onboard shall have sufficient capacity for how many minutes of operation? A.20 B.30 C.45 D.60 答案：B根据SOLAS公约，船上必须配备的呼吸器装置应该有足够的能力支持多少分钟？ 127.Where should you record the crude oil washing after completion? A.Oil Record Book B.Cow manual C.Pumping Log D.Inter plant manual 答案：A完成原油洗舱后你需要记录什么？油料记录簿 83.Shipboard Emergency Drills must be carried out at least_____? A.Once every third year B.Once a month C.Once a year D.Once a week 答案：B船舷应急计划必须执行至少每一个月一次

21,In anchoring orders , UP AND DOWN means__C__(老题库上的题)A the chain is not upright B the chain is tight C the chain is upright D the chain is slack 22 it is all right to rig the pilot ladder on lee side__A___ A to allow port Authorities to board B allowing port Authorities to board C to allow port Authorities boarding D allowing port Authorities to be boarded 23[4777]A spring line is ______.A.any wire rope used for mooring B.a fire-warp C.a mooring line running diagonally to the keel D.a mooring line perpendicular to the keel KEY: C 24[1317] Vessel towing with the current shall __C__ tow more than two boats and they must be towed alongside.A.at times B.at any time C.at no time D.at moment 25[1868] Your ship is steaming at night with the gyropilot engaged.You notice that the vessel’s course is slowly changing to the right.Which action should you take FIRST?__B____.A.Notify the engine room of the steering malfunction.B.Change to hand steering.C.Call the Master D.Send the Quartermaster to the emergency steering station.26when you are steering on a pair of range lights and find the upper light is in line above the lower light ,you should _A____ A continue on the present course B come left C come right D wait until the lights are no longer in a vertical line 27[1685] Which vessel is underway according to the Rules?___B___ A.A vessel made fast to a single point mooring buoy B.A purse seiner hauling her nets C.A pilot vessel at anchor D.A vessel which has run aground 28[2458]A vessel is in sight of another vessel when ______.A.she can be observed by radar B.she can be observed visually from the other vessel C.she can be plotted on radar well enough to determine her heading D.her fog signal can be heard KEY: B 29 0365 Every vessel shall at all times maintain a proper lookout ______.A.By sight.B.By sight and hearing.C.By sight and hearing as well as by all available means appropriate to the prevailing circumstances.D.By sight and hearing as well as by all available means except smelling.KEY：C每一船舶应一直通过视觉，听觉和一切适用于当时环境的适合手段保持适当的了望。(老题库)30[1475] When is a stand-on vessel FIRST allowed by the Rules to take action in order to avoid collision? B A.When the two vessels are less than half a mile from each other.B.When the give-way vessel is not taking appropriate action to avoid collision.C.When collision is imminent.D.The stand-on vessel is never allowed to take action.31[210]A light signal consisting of three flashes means ______.A.I am in doubt as to your actions B.My engines are full speed astern C.I desire to overtake you D.I am operating astern propulsion KEY: D 32[2703]______ means the curve on the earth's surface which cuts all the meridians at the same angle．

A.Great Circle B.Position Line C.Rhumb line罗盘方位；恒向线 D.True Bearing KEY: C 33[1749]Which word indicates color variation in the characteristics of a light? A.Opposing B.Changing C.Reversing D.Alternating---交替的，交流的，互光的，互光（指周期性变色的航标灯）KEY: D哪一个词说明灯光特性中的颜色变化？互光 34[2674]A SEAMARK，I.E.A BUOY，INDICATING THE NORTH，EAST，SOUTH OR WEST FROM A FIXED POINT，E.G.A WRECK is ______.A.Entrance buoy B.New buoy C.Port buoy D.Cardinal buoy KEY: D 35[821] Mean high water is the average height of _D_____ A.the higher high waters B.the lower high waters C.the lower of the two daily tides D.all high waters 36[149]The meaning of ebb tide is that ______.A.tide is falling from high water to low water B.tide is rising from low water to high water C.tide is reaching to a highest level D.tide is reaching to a lowest level KEY: A 37[5569]After transferring a weight forward on a vessel，the draft at the center of flotation will ______.A.change，depending on the location of the LCG B.increase C.decrease D.remain constant KEY: D 38[5575]If the buoyant force on a ship's hull is equal to the displacement tonnage，the ship will ______.A.require ballast B.be down by the head C.sink D.float KEY: D 39[5588]Reducing the liquid free surfaces in a vessel reduces the ______.A.roll period B.metacentric height C.waterplane area D.vessel's draft KEY: A 40 2116 How should you signal the crane operator to raise the boom?(老题库)A.Extend arm with the thumb pointing up and flex the fingers in and out.B.Place both fists in front of the body with the thumbs pointing upward.C.With forearm vertical and forefinger pointing up, move hand in small horizontal circles.D.Extend arm with fingers closed and point thumb upward.D你应怎样指挥起货机手提升吊杆？伸开臂膀手指握紧拇指向上 41 71.Where is the draft largest when the ship has an aft trim? A.Forward B.Aft C.Midships D.The drafts are equal all over the ship 答案：B当船舶尾倾时最大吃水在哪里？船尾 42 [3207]Filler cargo refers to ______.A.durable packages B.small pieces C.the cargo in which the voids appear D.the cargo suitable for stowage in void spaces KEY: D 43[3221]Strong smelling cargo should be stowed ______ the cargo absorbing foreign smell． A.together with B.on top of C.underneath D.away from KEY: D 44[4388]The damaged cargo is not allowed to export without ______.A.repairing or replacing B.to repair or to replace C.being repaired or replaced D.to be repaired or replaced KEY: C 45[4028]The Agent promised to keep me ______ of how our business was going on． A.to be informed B.informed C.on informing D.informing KEY: B 461993 The man directing and supervising the work of stevedores is the ______.(老题库)A.Local agent.B.Watchman.C.Docker.D.Foreman.指导和监督码头工人工作的人是工头。

471267 The tropical cyclone eastly 10 knots and expected ______ from 120000 GMT.A.Falling down.B.Fixing up.C.Filling up.D.Dropping down.热带气旋以10节的速度向偏东方向移动并预计自世界时12日0000起开始填塞。

48[1292] TYPHOON FORECAST MOVE 285 DEG 15 KNOT FIRST 12 HOURS THEN 280 DEG 17 KNOTS NEXT 12 HOURS.The movement of the Typhoon is in __C____ quadrant.A.NE B.SE C.NW D.SW 49[2820]Swell is the rise and fall of the ocean's surface due to ______.A.fetch B.distant winds C.local storms D.the pull of the moon KEY: B 50[331]Fog is most commonly associated with a(n)______.A.warm front at night B.low pressure area C.anticyclone D.lack of frontal activity KEY: A 51[3422]In most cases，the direction of the apparent wind lies between the bow and ______.A.the direction of the true wind B.true north C.the beam on the windward side D.the beam on the lee side KEY: A 52[3479]The inner bottom is the ______.A.tank top B.compartment between the tank top and shell of the vessel C.inner side of the vessel's shell D.space between two transverse bottom frames KEY: A 53___D___ is halfway between the forward and after perpendiculars and is reference point for vessel construction A half length B mid_body C center line D amidships 54119.Watertight compartments are separated by _____.A.Longitudinal bulkhead B.Tween decks C.Dunnages D.Decks and bulkheads 答案：D水密舱被垫板分开

55[823]The material used extensively as electrolytic protection around bronze propellers is ______.A.Brass B.Copper C.Lead D.Zinc KEY: D 56[3560]Before starting any diesel or gasoline engine，which of the following must be checked? A.Oil level B.Flow of cooling water C.Exhaust discharge D.All of the above KEY: A 57[5295]The holding capability of an anchor is primarily determined by the ______.A.shape of the anchor B.stowage of the anchor on board C.anchor's ability to dig in D.size of the vessel and its draft KEY: C 58.A Racon can help with _D_?A.measuring the distance B.measuring the relative C.identifying centimeters D.identifying a seamark 59.[3872]The radio waves used for radar are very short，only ______ long． A.a few centimeters B.a few fathoms C.a few meters D.a few feet KEY: A 60.103.What type of radar can activate a racon? A.X-band radar B.S-band radar C.C-band radar D.No radar can 答案：A什么类型的雷达能激活雷达信标？X波段的雷达 61.[3910]Magnetic variation changes with a change in ______.A.the vessel's heading B.sea conditions C.seasons D.the vessel's position KEY: D 62.[3818]Deviation is the angle between the ______.A.true meridian and the axis of the compass card B.true meridian and the magnetic meridian C.magnetic meridian and the axis of the compass card D.axis of the compass card and the degaussing meridian KEY: C 63.[15]Which one of the followings is incorrect about magnetic compass? A.The magentic compass is compulsory on my vessel B.The magentic compass is prone to error C.The magentic compass is always placed inside steel constructions D.The magentic compass needs to be calibrated to compensate for local magnetic distortion 答案：C关于磁罗经下面哪项是不正确的？磁罗经总是放在刚性结构里面

64.With respect to automatic identification systems(AIS)which of the following information is broadcast every one to ten seconds? C A.Vessel’s draft B.Air Draft C.Navigational status D.Dimensions of vessel 65.123.In case of AIS overload, what can you expect? A.AIS will shut down B.AIS will “freeze”

C.Largest far away drop out D.Closes targets drop out 答案：C如果AIS超负荷，你能预料到什么？当AIS超负荷最远的目标会退出录取

66.[17]What may affect the accuracy of sounding with echo sounder? A.Sea bottom B.Ship's speed C.Speed of current D.Water temperature and density 答案：D什么会影响回声探测仪的精度？水的温度和密度

67.[1625] Which piece of required GMDSS equipment is the primary source of transmitting locating signals? B A.Radio Direction Finder B.An EPIRB transmitting on 406 MHz C.Survival Craft Transceiver D.A SART transmitting on 406 MHz 68.[588] How can the SART’s audible tone monitor be used?__A____.A.It informs survivors that assistance may be nearby.B.It informs survivors when the battery’s charge condition has weakened.C.It informs survivors when the SART switches to the standby mode.D.It informs survivors that a nearby vessel is signaling on DSC.69.[180]The pilot {embarked} the ship at 1830 hours． A.boarded B.left C.piloted D.loaded KEY: A 70.[4194]There is a drifting mine ______ in position 21 degrees 31 minutes North 124 degrees 20 minutes East． A.report B.reports C.reported D.reporting KEY: C 71.[904] Please tell me ___B___ to reverse your engine from full ahead to full astern.A.how length will it take B.how long it will take C.how long will it get D.how much hours it will take 72.89.What is the meaning of the word “ROGER” when used in radio communication?

A.Please repeat your message B.Not readable C.Correct D.I have received your transmission satisfactorily 答案：D当使用无线电通信的时候单词“明白了”是什么意思？我已经满意的收到了你的传送

73.[4403]A bollard is found on the ______.A.beach B.deck C.pier D.towed vessel KEY: C 74.[4470]The heel block is located ______.A.at the base of the boom B.at the cargo hook C.near the midships guy D.near the spider band KEY: A吊杆座滑车

75.[594] How is the size of chain determined?___B___.A.Length of link in inches B.Diameter of metal in link in inches or centimeters C.Links per fathom D.Weight of stud cable in pounds 76.[226]A mooring line leading 45° to the keel，used to check forward or astern movement of a vessel，is called a ______.A.spring line B.warp line C.bow line D.breast line KEY: A 77.[4529]Vessel's provisions refer to ______ of the vessel． A.fuel oil B.vegetables and food C.spare parts on board D.ballast water KEY: B

78.[5656]A continuous sounding of a fog-signal apparatus indicates ______.A.the vessel is in distress B.the vessel has completed loading dangerous cargo C.it is safe to pass D.the vessel is anchored KEY: A 79.[1752]Instructions on how to conduct search and rescue are given in the ______ which is primarily designed for use by merchant ship.同原题库3240 A.MARPOL---Marine Pollution B.IRPCS---International Regulations for Prevention of Collisions at Sea C.SOLAS---Safety Of Life At Sea D.MERSAR---Merchant Ships Search And Rescue KEY: D主要被设计用于商船的MERSAR上给出了如何指挥搜索和救助的指导。80.[308] After using a CO2 portable extinguisher, it should be __D____ A.put back in service if some CO2 remains B.hydrostatically tested C.retagged D.recharged 81.[5803]A ROUND THROUGH THE VESSEL CARRIED OUT BY A CREW MEMBER OF THE WATCH AT CERTAIN INTERVALS SO THAT AN OUTBREAK OF FIRE MAY BE PROMPTLY DETECTED defines ______.A.Fire patrol B.Fire control C.Smoke detection D.Fire drill KEY: A 82.82.What is the meaning of UEL? A.Upper exposure level B.Upper explosion level C.Upper explosive level D.Upper evaporation level 答案：C UEL的意思是什么？爆炸上限

83.[4379]Puncture leaks in the lower tubes or bottom of an inflatable liferaft should FIRST be stopped by using ______.A.sealing clamps夹封 B.repair tape C.a tube patch D.sail twine and vulcanizing kit KEY: A 84[5865]If help has not arrived in 10-12 hours after you abandon a vessel in a survival craft，you should ______.A.go in one direction until the fuel runs out B.plot a course for the nearest land C.take a vote on which direction you should go D.shut down the engine(s)and set the sea anchor KEY: D 85.90.What type of oil is most suitable for reducing the effect of heavy seas? A.Crude oil B.Fuel oil C.Vegetable oil D.Lubricating oil 答案：C哪种油最适合减小波涛汹涌的海面的作用？植物油 86When the ship causes oil pollution to the port,she will be___B___ A、find B、levied C、paid D、deducted [87]In all but the most severe cases，bleeding from a wound should be controlled by _____A_.A.applying direct pressure to the wound B.submerging the wound in lukewarm water C.cooling the wound with ice D.applying a tourniquet [88]A crew member suffering from hypothermia should be given ___B___.A.a small dose of alcohol B.treatment for shock C.a large meal D.a brisk rub down 一

BISCAY：SW 3 OR 4 INCREASING 6 TO GALE 8，THEN VEERING NW 5．RAIN THEN SHOWERS．MODERATE OR POOR BECOMING GOOD．FINISTERRE： WESTERLY 6，LOCALLY GALE 8，VEERING NW 5．RAIN THEN SHOWERS．MODERATE OR POOR BECOMING GOOD．EAST NORTHERN SECTION：W OR SW 6 TO GALE 8，BUT IN NORTH-EAST CYCLONIC 4 AT FIRST，AND IN NORTH-WEST SOUTHERLY 6 TO GALE 8 AT FIRST．WINTRY SHOWERS．MAINLY GOOD．WEST NORTHERN SECTION：IN NORTH，CYCLONIC 6 TO GALE 8，LOCALLY SEVERE GALE 9，BECOMING VARIABLE 3 OR 4．WINTRY SHOWERS．MAINLY GOOD．MODERATE ICING IN WEST AT FIRST WITH TEMPERATURE-2℃ TO-5℃．IN SOUTH WESTERLY 6 TO GALE 8，LOCALLY SEVERE GALE 9，BACKING SOUTHERLY AND INCREASING LOCALLY STORM 10 LATER．WINTRY SHOWERS THEN SNOW．MAINLY GOOD BECOMING MODERATE． [89].Backing means the wind ____B___． A．is changing clockwise in direction B．is changing anticlockwise in direction C．is changing cyclonically or variably in direction D．remains unchanged in direction at the time [90].The visibility in EAST NORTHERN section is mainly ___C____． A．poor B．moderate C．GOOD D．very GOOD [91].In north part of WEST NORTHERN section，the wind is ____A___． A．cyclonic 6 to gale 8 at first B．cyclonic 4 at first C．westly 6 to gale 8 D．variable 3 or 4 at first [92].This passage is likely to be under the heading of ____A____． A．FORECAST B．GALE WARNING C．SYNOPSIS D．STORM WARNING 二

The Chief Officer，or First Mate as he is often called，is the Master's chief officer and head of the Deck Department．He is assisted by a Second Officer（Mate），a Third Officer（Mate），and sometimes a Fourth Officer（Mate）．Several companies employ a First Officer as well as a Chief Officer．The Deck Department also includes a Boatswain（Bosun）and a Carpenter，both petty officers，and a number of ratings．These made up of Able Seamen（AB），Ordinary Seamen（OS）and a middle grade known as Efficient Deck Hands（EDH）．There are other grades of seamen．On some ships Navigating Cadets are carried for training purposes．

The Chief Engineer is head of the Engine Department．He is assisted by a Second，Third，Fourth and sometimes Fifth Engineer．An Electrical Officer may also be carried．The engine room petty officers are the Storekeeper and Donkeyman．On tankers there is also a Pumpman．He is also a petty officer．The engine room ratings are Firemen and Greasers．There may also be Engineer Cadets．

The Catering Department is under the Chief Steward．It is divided into a saloon and galley section．The former is headed by the Second Steward，the latter by the Ship's Cook．They are both usually petty officers．They are assisted by several stewards and cooks，and by a number of junior ratings．

The Radio Department often consists of only one man：the Radio Officer．On ships where continuous radio watches are kept there may be three radio officers：a Chief，Second and Third． [93].____C____ is not a petty officer．

A．Boatswain B．Second Steward C．Radio Officer D．Storekeeper [94].EDH is rank which is higher than ____C____． A．Second Steward B．AB C．OS D．Chief Engineer [95].Storekeeper belong to _____B___．

A．Deck Dept B．Engine Dept C．Catering Dept D．Radio Dept [96].There are _____C___ departments on bard a big ship according to the passage． A．two B．three C．four D．five

第三篇：怎样保护牙齿教案

怎样保护牙齿教案

教学设计:

一、教学理念

根据陶行知先生“生活即教育”、“社会即学校”、“教学做合一”的原则。我在设计本堂课时结合现在学生中比较普遍的龋齿(蛀牙)问题,进行探讨。让学生知道龋齿(蛀牙)的危害,并使之能自觉地养成良好的习惯。为了引起学生强烈的共鸣,我通过较为形象的动画图片,让学生直观的了解,并引起触动,以起到更好的效果。做到“在生活里找教育,为生活而教育”。

二、教学目标:

1、知道整齐洁白的牙齿有益身体健康,懂得要保护牙齿的道理。

2、初步学会防治牙病,保护牙齿的方法。

3、养成保护牙齿的习惯

三、教学重、难点:

1、重点:初步学会保护牙齿最常用的几种方法。

2、难点:养成保护牙齿的习惯。

四、教学准备

课件动画、模型牙齿、模型牙刷

五、教学过程:

(一)活动一:谜语激趣 认识牙齿

谜语导入:孩子们,我给你们带来了一个新朋友,不过它呀,就藏在谜语里,你们若是猜不着,它可就不和你们交朋友。(上一排,下一排,整整齐齐白又白。你要猜不着,张开嘴巴就明白。)课件出示牙齿的图片。

小朋友,刚才你们猜谜语猜的又快又好,老师奖励你们一份礼物,快看看是什么礼物?(花生)快尝一尝花生香不香。

师:你们是怎样吃花生的?(剥开来吃)

师:花生一粒一粒又是怎么吃到肚子里的?(用牙嚼碎)

师:别的东西又是怎样吃到肚子里的呢?(也是用牙嚼碎)

师:小朋友吃花生要用牙齿嚼碎,小兔吃萝卜,小狗啃骨头要用什么嚼碎(牙齿)

如果没有牙齿,小狗还能啃骨头,小兔还能吃萝卜吗?(不能)

师小结:我们的牙齿又白有坚硬,它的用处可大了,能够咬断食物,嚼碎食物帮助消化,可牙齿吃完东西后是怎样的呢?是不是很脏?

2、学生漱口,一起看漱口水。发现水很脏,激起自己漱口的愿望。

教师小结:如果我们吃完东西后不去漱口,那些残留在牙缝里的食物就会变质,就把我们又白又坚硬的牙齿给腐蚀掉,就会有小虫子来吃掉我们的牙齿,如果不信,看完下面这个动画片就会明白.放《老虎拔牙》课件动画:(老虎自认为牙齿锋利,结果因吃过多甜食,又不刷牙而导致蛀牙,全被拔光。)

师:看了动画,你想想为什么老虎的牙齿会拔光呢?

生:太爱吃糖了。

生:每天不刷牙。

生:平时不注意卫生。

……

师:对了,就是因为它没有保护好,所以牙齿才会——

生:蛀掉。

师:(出示课题)今天我们就来学习“怎样保护牙齿”。(通过直观形象的动画,让学生明白蛀牙的危害,以起到警示作用。)

(二)讨论研究

师:怎样才能保护好牙齿呢?小朋友四人小组讨论讨论。

(生讨论)

汇报:

生:每次吃完东西漱漱口。

生:每天睡觉之前刷刷牙。

生:平时少吃甜的东西。

生:要是吃了东西不刷牙,虫子就要爬出来,牙齿就要蛀掉。

…… ……

师:刚才,小朋友们说的都很好。但是蛀牙并不是虫咬的,而是吃了糖或甜的食物后,碎屑留在牙齿表面或牙缝中,在口腔中的变形链球菌等产酸菌的作用下产生酸。牙齿中的钙、磷等成分渐渐被酸溶解破坏,出现了蛀洞。馒头、米饭及糕点等食物残屑,经过唾液作用变成糖留在牙缝中,也会产生蛀牙。

师:现在让我们来看看牙齿是怎样蛀空的。(看课件:牙齿一步步被蛀的过程。)

师:这样的结果,相信大家谁也不想遇到,可是就是有很多同学不注意口腔卫生,说说你平时是怎么对待牙齿的?今后怎么做?(学生自由发言)

生:我平时睡觉之前不刷牙,今后我会每天刷牙的。

生:我每次吃完饭都不漱口,以后我会漱口的。

生:我以后少吃点甜的。

…… ……

(通过探讨,观看课件,进一步引起学生对蛀牙的重视,并使之能自觉养成保护牙齿的习惯。)

(三)保健预防

师:现在请你当当小医生,同桌互相检查一下,看看有没有病牙。

(同桌进行检查汇报)

师:如果你有病牙,或是牙面上有黑点,要及时治疗,防止蛀牙的进一步发生。

师:如果是健康的牙齿,就应及时预防,如果已经有病牙,更要注意口腔卫生。最好的预防方法如饭后漱口,早晚刷牙,睡前不吃东西等。刷牙的方法也是很重要的。

师示范:(出示一支大牙刷和牙齿模型)刷牙时要采用竖刷的方法,把牙缝中存留的残屑都清理干净,并使每个牙面都能刷到,刷牙不仅可以清洁牙齿,还对牙床有按摩保健作用。(请学生学做)

学习刷牙的儿歌:小牙刷,刷呀刷,上牙从上往下刷;下牙从下往上刷,咬合面要来回刷.早晚坚持刷一刷,牙齿洁白人人夸!

学生两人一组进行刷牙练习,互相纠正.教师巡视帮助.教师请不同学生上台示范,请学生自己评价.(通过师的讲解示范和儿歌练习,激发学生学习兴趣,让学生明白应及时预防,并掌握正确的刷牙方法。)

(四)舞蹈:<刷牙歌>

师:学了这么多,下面就让我们一起来跳一个刷牙的舞蹈吧!跟着音乐一起来,看谁跳得棒!(教师带领学生跳)

(五)总结

师:通过今天的学习,你想对那只被拔了牙齿的老虎说些什么?提些什么建议?

生:老虎,你要每天刷牙。生:老虎,你不要吃那么多糖。

生:老虎,你吃完东西要漱漱口。

生:你不要那么贪吃。

…… ……

师:我们从小就要保护牙齿,牙齿一旦生病,就会引起全身各个器官的毛病,影响人的健康成长,所以我们从小要——

生:保护牙齿。

(让学生在学完整堂课时,知道自己在今后的生活中该怎样做。真正做到“生活即教育”、“社会即学校”、“教学做合一”。)

第四篇：牙齿护理的标准是什么

南昌数字口腔中心（科普知识宣传）

牙齿护理的标准是什么

以前很多人往往都会忽视牙齿的健康，但是随着现在人们生活水平的提高和牙齿疾病越来越多,人们对牙齿的健康也越来越关注了。牙齿护理的标准是什么?具体内容如下所示：

1.基本标准：牙齿干净魅力值★

这是最容易做到的，是美的最基本条件。即使你的牙齿不是很完美，如果清洁得很好，没有牙菌斑、色素、牙结石，口气清新，也会给人一种清洁的感觉。

2.初级标准：牙齿整齐魅力值★★

排列的比较整齐的牙齿，会让人有种自信，特别是在露齿而笑时能给人很亲和的感觉。而且整齐的牙齿可以进行充分的咀嚼，帮我们获得平衡的口腔关系，促进肠胃消化吸收。所以，它不仅仅是外在美的一个标准，也是判断我们健康的一个标准。

3.高级标准：牙齿洁白魅力值★★★

古今中外主流的美学价值取向中，人们对容貌美的要求都有一项——皓齿，即洁白的牙齿，这意味着阳光饱满、身体健康。而且从口腔医学上讲，人的年龄增大，牙齿颜色会逐渐变黄、变暗，追求“更白、更亮”的牙齿已经成为更有青春活力、更年轻亮丽的象征。

4.顶级标准：美魅力值★★★★

这个标准看似简单，实际上大有讲究。它主要指牙齿与口唇的位置关系、牙齿之间的比例关系、牙齿长度与宽度的比例关系的调整，牙齿的排列方向、角度、倾斜度、扭转度的细微变化，每颗牙齿形态的精细调整等，这些细微的改动都有可能影响到我们的面部魅力。

第五篇：如何护理牙齿保护牙龈

南昌数字口腔专科（科普知识宣传）

如何护理牙齿保护牙龈

如何护理牙齿保护牙龈?专家介绍说，护理牙齿保护牙龈对我们每个人来说都很重要，特别是一些准妈妈。在怀孕期间发现自己非常容易刷牙出血，越是出血越不敢刷，最后更加严重。下面我们来看看怎么用正确的刷牙方法来减轻或避免孕期的刷牙出血，既不伤害牙齿，又能保健牙龈。

如何护理牙齿保护牙龈?主要可以采用以下一些方法：

一、不伤牙齿：采用竖刷法，即上牙朝下刷，下牙朝上刷，由牙龈到牙齿，动作要轻柔，使用软毛牙刷，每组2～3颗牙，每组刷10下左右，遇到牙龈出血者，可以将次数增加到20次。这样从牙龈滑动到牙齿上的竖刷法，对牙龈的保健作用很好，也可以避免牙刷损伤釉(尤其是牙齿颈部）!

二、牙缝和牙面刷得干净：垂直刷牙有利于牙刷毛进入牙缝，利用牙刷毛的弹力，将牙缝的食物残渣等杂物刷出来。

三、促进牙龈的血液循环：牙刷的压力均匀地、多次反复地压迫牙龈，发挥牙刷按摩牙龈的作用，能促进牙龈血液流通，促进牙龈袋内的炎性分泌物排出，有利于牙龈组织的健康。

如何护理牙齿保护牙龈?注意口腔卫生。每次食后应漱口，正确的漱口方法为将溶液含在口内，闭口鼓动两颊和唇部，利用水力反复冲击口腔各个部位。做到食后3分钟刷牙，每次刷牙3分钟，每天刷牙3次，有困难者，早晚各刷牙1次。

如何护理牙齿保护牙龈?合理饮食调摄。提倡多食粗糙和纤维素丰富的耐磨食物，充分咀嚼。少食糖类及甜食，蔗糖对龋齿的发生起着决定性的作用。临睡前严禁吃糖果点心，因为甜味食物在口腔中的残余糖质不易被彻底清除。食谱应广泛，不可偏食，应多食新鲜水果、瓜类以补充维生素。实验已证明，饮茶确能提高牙齿防龋抗龋的能力。