Sự Lệch Lạc Khớp Cắn

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5/5/16 n  Lệch lạc khớp cắn: lệch lạc tương quan hàm và/hoặc hai hàm, ảnh hưởng đến sức khỏe cá nhân n  Phân loại khớp cắn: mô tả biến thể mặt khác dựa theo tiêu chuẩn bình thường n  Có nhiều cách phân loại khác LỆCH LẠC KHỚP CẮN TS Hoàng Việt Hải ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Lệch lạc khớp cắn xếp vào ba loại chính: Sai lạc vị trí Sai lạc tương quan cung Sai lạc tương quan xương Tâm lý: Một đặn với nụ cười hấp dẫn mang lại trạng thái tích cực cho người tầng lớp xã hội lứa tuổi Ngược lại, hàm lệch lạc vẩu gây trạng thái tâm lý tiêu cực Các loại tồn riêng lẻ phối hợp ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Chức miệng: Lệch lạc KC ảnh hưởng đến chức năng, thực tế khó định lượng xác mức độ ảnh hưởng Ngồi ra, lệch lạc KC ảnh hưởng đến phát âm ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Chấn thương Bệnh miệng: Lệch lạc KC, đặc biệt vẩu cửa HT, làm tăng khả chấn thương Cứ ba bệnh nhân có sai KC loại II khơng điều trị có người có khả bị chấn thương cửa mức độ khác 5/5/16 ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Chấn thương Bệnh miệng: Chấn thương Bệnh miệng: Những trường hợp khớp cắn sâu mà cửa HD tiếp xúc với vòm miệng gây chấn thương mơ đáng kể PRACTICE dẫn đến cửa HT số bệnh nhân PRACTICE Sai KC yếu tố góp phần gây bệnh sâu bệnh quanh răng, cản trở việc chăm sóc vệ sinh miệng gây sang chấn KC PRACTICE vidual will receive from this will depend on the severity of the presenting malocclusion as well as the patients own perception of the problem vidual will receive from this will depend on the Some individuals can have a marked degree of severity of the presenting malocclusion as well as dento-facial deformity and be unconcerned with the patients own perception of the problem theirindividuals appearance a practitioner Some canAlthough have a marked degree ofmay suggest treatment for besuch an individual, dento-facial deformity and unconcerned with patients should not be talked into treatment their appearance Although a practitioner mayand must betreatment left to make themsuggest for the suchfinal an decision individual, selves.should Mild malocclusions should be treated patients not be talked into treatment andwith caution Not only will the net improvement in the must be left to make the final decision themappearance of the teeth be small, but also selves Mild malocclusions should be treated with as nearlyNot all teeth move some degree after orthocaution only will thetonet improvement in the dontic treatment riskbeofsmall, relapsebut in these cases appearance of the the teeth also as is high Whilst minor movements afterorthothe cornearly all teeth move to some degree after dontic treatment themalocclusions risk of relapse in these rection of severe will stillcases produce is ahigh Whilst minor movements after the corsubstantial net overall improvement for the rection of severe malocclusions still produce patients, the same is not truewill of minor problems a Many substantial net overall for the the practitioners willimprovement have encountered patients, same not true of minorrotation problems parent the who canisspot a 5-degree of an Many will have theconupperpractitioners lateral incisor from fiftyencountered metres and is parent who a 5-degree rotation of an vinced thiscan willspot be the social death of their child upper lateral incisor fifty metres and or is conRegardless of howfrom insistent the parent child is, vinced this will be the social death of such their problems child the practitioner should approach Regardless of how insistent the parent or child is, the practitioner should approach such problems Fig A traumatic anterior occlusion is displacing the Fig 6right A traumatic lower central anterior occlusion incisor labially and is displacing there is an the lower right central associated incisor labially and dehiscence there is an associated dehiscence Fig The same patient as in Fig 6, Fig.the The same but cross bite patient in Fig 6, has beenas corrected but the cross bite with a removable has been corrected appliance and with has a removable there been appliance and an improvement has been inthere the gingival an improvement condition in the gingival condition Fig A traumatic anterior occlusion is displacing the lower right central incisor labially and there is an associated dehiscence Fig The same patient as in Fig 6, but the cross bite has been corrected with a removable appliance and there has been an improvement in the gingival condition Table Index of Treatment Need Dental health component Treatment need Table Index of Treatment Need Dental health component spontaneously and no long-term problems usually develop and no long-term problems ususpontaneously overbites can occasionally cause stripallyDeep develop ping of overbites the soft tissues as shown cause in Figure Deep can occasionally strip-8a and b is a tissues case where thereinisFigure little aesping of This the soft as shown 8a thetic treatment the and b need This isfor a case where but therebecause is little of aesthetic need for there treatment but because of theto deep overbite is substantial damage deep overbite there is substantial the soft tissues Clearly if this isdamage allowedtoto the soft tissues is allowed continue there isClearly a riskifofthis early loss of to the continue there that is a would risk of produce early loss of the lower incisors a difficult lower incisors that would produce a difficult restorative problem restorative problem WHO SHOULD BE TREATED? WHO BE TREATED? DentalSHOULD irregularity alone is not an indication for Dental irregularity alone is nottreatment an indication for treatment Most orthodontic is carried treatment Most orthodontic is carried out for aesthetic reasons andtreatment the benefit an indiout for aesthetic reasons and the benefit an indi- 2 3 Treatment need No need Aesthetic component Chấn thương Bệnh miệng: 1 2 3 4 5 6 7 8 9 10 10 Treatment need Treatment need Little need Little need Moderate need Sai KC yếu tố góp phần gây bệnh sâu Moderate need bệnh quanh răng, cản trở việc chăm sóc vệ sinh miệng gây sang chấn KC Great need Great need Table Index of Treatment Need Dental health component spontaneously and no long-term problems usually develop Deep overbites can occasionally cause stripping of the soft tissues as shown in Figure 8a and b This is a case where there is little aesthetic need for treatment but because of the deep overbite there is substantial damage to the soft tissues Clearly if this is allowed to continue there is a risk of early loss of the lower incisors that would produce a difficult restorative problem Little need No need LittleModerate need need Great need Moderate need Very great need need ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Great Very great need Aesthetic component vidual will receive from this will depend on the severity of the presenting malocclusion as well as the patients own perception of the problem Some individuals can have a marked degree of dento-facial deformity and be unconcerned with their appearance Although a practitioner may suggest treatment for such an individual, patients should not be talked into treatment and must be left to make the final decision themselves Mild malocclusions should be treated with caution Not only will the net improvement in the appearance of the teeth be small, but also as nearly all teeth move to some degree after orthodontic treatment the risk of relapse in these cases is high Whilst minor movements after the correction of severe malocclusions will still produce a substantial net overall improvement for the patients, the same is not true of minor problems Many practitioners will have encountered the parent who can spot a 5-degree rotation of an upper lateral incisor from fifty metres and is convinced this will be the social death of their child Regardless of how insistent the parent or child is, the practitioner should approach such problems Tại cần phải phân loại lệch lạc khớp cắn? WHO SHOULD BE TREATED? Dental irregularity alone is not an indication for treatment Most orthodontic treatment is carried out for aesthetic reasons and the benefit an indi- Loại lệch lạc khớp cắn liên quan chặt chẽ 10 Treatment need Little need Moderate need Great need Fig 8b The same patient as in Fig 8a, but not in occlusion The deep bite has resulted in labial stripping of the periodontium on the lower right central incisor 436 436 436 Aesthetic component Treatment need No need Little need Moderate need Great need Very great need đến việc lập kế hoạch tiến hành điều trị Fig 8a This malocclusion has an extremely deep bite which can be associated with potential periodontal problems Fig.8a 8aThis Thismalocclusion malocclusion has an extremely Fig extremelydeep deepbite bitewhich which canbe beassociated associated with with potential periodontal can periodontalproblems problems BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 Fig 8b8b The same patient as in 8a,8a, butbut notnot in in Fig The same patient as Fig in Fig occlusion The deep bite hashas resulted in labial stripping occlusion The deep bite resulted in labial stripping ofof the periodontium on on thethe lower right central incisor the periodontium lower right central incisor BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 SAI LẠC VỊ TRÍ RĂNG SAI LẠC VỊ TRÍ RĂNG Răng nghiêng gần Răng nghiêng phía gần, thân phía gần so với chân 5/5/16 SAI LẠC VỊ TRÍ RĂNG Răng nghiêng xa Răng nghiêng phía xa, thân phía xa so với chân SAI LẠC VỊ TRÍ RĂNG Răng nghiêng ngồi Răng nghiêng phía mơi (răng trước) má (răng sau) SAI LẠC VỊ TRÍ RĂNG Răng trồi Răng nằm cao mặt phẳng cắn so với khác cung SAI LẠC VỊ TRÍ RĂNG Răng nghiêng Răng nghiêngvề phía lưỡi (hàm dưới) hay vòm miệng (hàm trên) SAI LẠC VỊ TRÍ RĂNG Răng cắn hụt Răng thấp mặt phẳng cắn so với khác cung SAI LẠC VỊ TRÍ RĂNG Răng xoay Gần xa ngoài: Mặt gần nghiêng phía trong, mặt xa thân nằm phía so với mặt gần 5/5/16 SAI LẠC VỊ TRÍ RĂNG Răng xoay Xa hay gần ngồi: Mặt xa nghiêng phía trong, mặt gần thân nằm phía ngồi so với mặt xa LỆCH LẠC TƯƠNG QUAN CUNG RĂNG SAI LẠC VỊ TRÍ RĂNG Răng hốn đổi vị trí Đây trường hợp hai thay đổi vị trí cho Khi hai cung rng vị trí khớp cắn trung tâm, có quan hƯ c¸c theo ba hưíng: Tr­íc –sau (gÇn –xa)" Ngang" Đøng" 5/5/16 LỆCH LẠC THEO CHIỀU TRƯỚC - SAU Phân loại sai khớp cắn theo Angle Khớp cắn bình thường theo Angle Cơ sở: Tương quan hàm hàm hai hàm cắn khít, xếp liên quan tới đường cắn Đỉnh múi gần hàm lớn thứ hàm trùng với rãnh hàm lớn thứ hàm lại xếp đường cong đặn liên tục Phân loại sai khớp cắn theo Angle Angle xếp sai khớp cắn thành ba loại chính, kí hiệu theo chữ số La mã – I, II III 5/5/16 Phân loại lệch lạc khớp cắn theo Angle n  Lệch lạc khớp cắn loại I Tương quan khớp cắn vùng hàm lớn thứ bình thường đường khớp cắn không mọc không vị trí, xoay nguyên nhân khác Angle s Class I Angle s Class II Angle s Class III Khe thưa Răng mọc chen chúc 5/5/16 Lệch lạc khớp cắn loại II n  Đỉnh múi gần hàm lớn thứ hàm phía gần so với rãnh ngồi hàm lớn thứ hàm 5/5/16 Lệch lạc khớp cắn loại III n  Lệch lạc khớp cắn loại III Đỉnh múi gần hàm lớn thứ hàm nằm phía xa so với rãnh hàm lớn thứ hàm Lệch lạc khớp cắn loại III 5/5/16 Độ cắn chìa The centre line should be measured by placing a ruler down the patient's facial mid-line and measuring how far away from this the centre lines deviate (Fig 4) This can then be marked in the notes as shown in Figure The buccal occlusion is assessed next, particularly the molar relationship This is important because when assessing the treatment, it has to be decided whether the buccal occlusion The centre line should be measured by placis to be accepted or whether it should be coring a ruler down the patient's facial mid-line and rected as part of the treatment plan The canine measuring how far away from this the centre and molar relationships should be recorded as Fig This Method recording deviations lines deviate (Fig 4) can for then be marked in in the centre line where the lower is to the right by 1mm class I, II or III the notes as shownand in the Figure upper5.to the left by mm Finally, the presence of any anterior or posThe buccal occlusion is assessed next, parterior cross-bites should be assessed and if ticularly the molar relationship This is importhere is a cross-bite, the clinician should check tant because when assessing the treatment, it • Class I The lower incisor edges occlude with to see whether there is any mandibular dishas to be decidedor whether the buccal occlusion lie immediately below the cingulum plateau placement associated with it This is important is to be accepted(middle or whether it the should cor- incisors part of) upperbe central because any displacement will mask the posirected as part of• the treatment plan.incisor The canine Class II The lower edges lie posterior tion of the teeth and give a misleading indicaand molar relationships should be recorded asupper central tion of the inter-occlusal relationships Figure to the cingulum plateau of the class I, II or III incisors There are two divisions: shows a child who has an apparently severe Finally, the presence anterior or pos- in the overjet class III incisor relationship However, he can Divisionof1 any — there is an increase terior cross-bitesand should be assessed and if are usually get his teeth into an edge-to-edge relationship the upper central incisors proclined and in this position the occlusion does not there is a cross-bite, the clinician should check Division — mandibular the upper central to see whether there is any dis- incisors are appear to be so severe The amount of procliretroclined overjet is usually minimal but nation of the upper incisors needed to correct placement associated with it.The This is important may be increased the incisor relationship was quite mild and because any displacement will mask the posiClassgive III The lower incisor edges lie anterior easily accomplished Fig Measurement of centre line using a removable applition of the teeth• and a misleading indicato the cingulum plateauFigure of the6upper deviation central using ancea (Fig and in 8) ruler placed PRACTICE tion of the inter-occlusal relationships the patient's mid line incisors The apparently overjet is reduced or reversed shows a child who has an severe PRACTICE Fig Method for recording deviations in the centre line where the lower is to the right by 1mm and the upper to the left by mm • Class I The lower incisor edges occlude with or lie immediately below the cingulum plateau (middle part of) the upper central incisors • Class II The lower incisor edges lie posterior to the cingulum plateau of the upper central incisors There are two divisions: Division — there is an increase in the class III incisor relationship However, he can The centre line overjet should be measured by placing a ruler down patient's facialget mid-line and the upper central incisors are theusually hisandteeth into an edge-to-edge relationship measuring how far away from this the centre proclined in inthis position the occlusion does not lines deviate (Fig 4) This can thenand be marked the notes as shown in Figure Division — the upper central incisors are appear to be so severe The amount of procliThe buccal occlusion is assessed next, parvidual will receive from this will retroclined depend on theThe overjet is usually minimal but This nation of the upper incisors needed to correct ticularly the molar relationship is imporseverity of the presenting malocclusion as well as tant because when assessing the treatment, it may be increased the incisor relationship was quite mild and has to be decided whether the buccal occlusion the patients own perception of the problem to be accepted or whether it should be cor• Classdegree III The edges lie anterior easily accomplished using a removable appliSome individuals can have a marked of lower incisoris rected as part of the treatment plan The canine to the cingulum ofand the upper central (Fig dento-facial deformity and be Fig unconcerned withdeviations plateau molar relationships should beance recorded as and 8) Method for recording in the centre line where the lower the right by 1mm class I,or II or III their appearance Although aand practitioner may incisors Theis tooverjet is reduced reversed the upper to the left by mm PRACTICE Fig A traumatic anterior occlusion is displacing the lower right central incisor labially and there is an associated dehiscence PRACTICE vidual will receive from this will depend on the severity of the presenting malocclusion as well as the patients own perception of the problem Some individuals can have a marked degree of dento-facial deformity and be unconcerned with their appearance Although a practitioner may Fig The same patient as in Fig 6, suggest treatment for such an individual, but the cross bite patients should not be talked into treatment and has been corrected must be left to make the final decision themwith a removable selves Mild malocclusions should be treated with appliance and caution Not only will the net improvement in the there has been appearance of the teeth be small, but also as an improvement in the gingival nearly all teeth move to some degree after orthocondition dontic treatment the risk of relapse in these cases is high Whilst minor movements after the correction of severe malocclusions will produceproblems ususpontaneously and nostill long-term a substantial net overall improvement for the ally develop patients, the sameDeep is notoverbites true of minor problems cause stripcan occasionally Many practitioners encountered the in Figure 8a ping ofwill thehave soft tissues as shown parent who can a 5-degree rotation an is little aesandspot b This is a case whereof there upper lateral incisor and isbut contheticfrom needfifty for metres treatment because of the vinced this willdeep be the social death child damage to overbite there ofistheir substantial Regardless of how the parent or if child the insistent soft tissues Clearly thisis,is allowed to the practitionercontinue should approach there is asuch riskproblems of early loss of the Fig A traumatic anterior occlusion is displacing the lower right central incisor labially and there is an associated dehiscence Fig The same patient as in Fig 6, but the cross bite has been corrected with a removable appliance and there has been an improvement in the gingival condition lower incisors that would produce a difficult Table Index ofrestorative Treatment Need problem Dental health component spontaneously and no long-term problems usually develop Deep overbites can occasionally cause stripping of the soft tissues as shown in Figure 8a and b This is a case where there is little aesthetic need for treatment but because of the deep overbite there is substantial damage to the soft tissues Clearly if this is allowed to continue there is a risk of early loss of the lower incisors that would produce a difficult restorative problem Treatment need WHO SHOULD BE TREATED? No need Dental irregularity alone is not an indication for needorthodontic treatment is carried treatment.Little Most Moderatereasons need out for aesthetic and the benefit an indi- Aesthetic component Great need Very great need suggest treatment for such an individual, patients should not be talked into treatment and • Classdecision I The lowerthemincisor edges occlude with must be left to make the final or lie immediately below the cingulum plateau selves Mild malocclusions should bepart treated with central incisors (middle of) the upper caution Not only will the net• improvement the edges lie posterior Class II The lowerinincisor the cingulum plateau appearance of the teeth be to small, but also asof the upper central incisors There are two divisions: nearly all teeth move to some Division degree1after — thereorthois an increase in the overjet and theinupper dontic treatment the risk of relapse thesecentral casesincisors are usually proclined is high Whilst minor movements after the corDivision — the upper central incisors are rection of severe malocclusions will still retroclined Theproduce overjet is usually minimal but may be increased a substantial net overall improvement for the Class III Theproblems lower incisor edges lie anterior patients, the same is not true• of minor to the cingulum plateau of the upper central Many practitioners will haveincisors encountered The overjet isthe reduced or reversed parent who can spot a 5-degree rotation of an upper lateral incisor from fifty metres and is convinced this will be the social death of their child Regardless of how insistent the parent or child is, the practitioner should approach such problems Table Index of Treatment Need Dental health component Treatment need No need Little need Moderate need Aesthetic component Finally, the presence of any anterior or posterior cross-bites should be assessed and if there is a cross-bite, the clinician should check to see whether there is any mandibular displacement associated with it This is important because any displacement will mask the posiFig Measurement of centre line tion of the teeth and give a misleading indicadeviation using a ruler placed in tion of the inter-occlusal relationships Figure 6 Class Fig III mid line the patient's shows a child who has an apparently severe with a class III incisor relationship However, he malocclusion can displacement get his teeth into an edge-to-edge relationship and in this position the occlusion does anteriorly not The patient appear to be so severe The amount of proclican achieve an edge to nation of the upper incisors needed to correct the incisor relationship was quite mild edge and incisor relation in easily accomplished using a removable applithe retruded position ance (Fig and 8) of the mandible Fig Class III malocclusion with a displacement anteriorly The patient can achieve an edge to edge incisor relation in the retruded position of the mandible Fig Upper removable appliance us anterior cross bite Fig The corrected incisor position for the patient Fig Upper removable appliance used to correct the anterior cross bite Fig Upper removable appliance used to correct the anterior cross bite Fig The corrected incisor position for the patient Fig Class III malocclusion with a displacement anteriorly The patient can achieve an edge to edge incisor relation in the retruded position of the mandible Fig The corrected incisor position for the patient Great need Very great need Treatment need BRITISH DENTAL JOURNAL VOLUME 195 NO 10 NOVEMBER 22 2003 Little need 10 Moderate need Great need BRITISH DENTAL JOURNAL VOLUME 195 NO 10 NOVEMBER 22 2003 565 BRITISH DENTAL JOURNAL VOLUME 195 NO 10 NOVEMBER 22 2003 565 Treatment need Little need Moderate need WHO SHOULD BE TREATED? Dental irregularity alone is not an indication for Great need 8a This malocclusion treatment Most orthodontic treatment isFig carried 10 has an extremely deep bite which be associated with potential periodontal problems out for aesthetic reasons and the benefit can an indi- 436 Lệch đường Fig 8b The same patient as in Fig 8a, but not in occlusion The deep bite has resulted in labial stripping of the periodontium on the lower right central incisor BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 LỆCH LẠC THEO CHIỀU NGANG Fig 8a This malocclusion has an extremely deep bite which can be associated with potential periodontal problems 436 Fig M deviatio the patie Fig 8b The same patient as in Fig 8a, but not in occlusion The deep bite has resulted in labial stripping of the periodontium on the lower right central incisor BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 Anterior Tooth Positions ƒ Overjet is a term used to Transverse Dental Relationships describe the distance between the labial surfaces of the mandibular incisors and the incisal edge of the maxillary incisors 5/5/16 ƒ Anterior Crossbite is a malrelation between the maxillary and mandibular teeth when they occlude with the antagonistic tooth in the opposite relation to normal Khớp cắn chéo hàm Posterior Crossbites ƒ A Posterior Crossbite is present when posterior teeth occlude in an abnormal buccolingual relation with the antagonistic teeth ƒ Posterior Crossbites can be the result of either malposition of a tooth or teeth, and/or the skeleton ƒ Examining the transverse dimension allows us to evaluate the intermolar and intercanine widths and determine which arch is the offending unit ƒ Posterior crossbites can be unilateral or bilateral ƒ A Functional Crossbite results from an occlusal interference that requires the mandible to shift either anteriorly and/or laterally in order to achieve maximum occlusion Khớp cắn chéo hàm Posterior Crossbite 08p449-455.qxd 24/03/2004 10:42 Page 455 P Fig 8a,b A right-sided cross bite has produced substantial occlusal wear This would be impossible to correct restoratively with this occlusion Fig 8c An upper fixed appliance with a quad helix was used to expand the upper arch, correct the incisor relationship and align the teeth Khớp cắn chéo hàm PRACTICE Fig A traumatic anterior occlusion is displacing the lower right central incisor labially and there is an associated dehiscence ACTICE Fig The same patient as in Fig 6, but the cross bite has been corrected with a removable appliance and there has been an improvement in the gingival condition g A traumatic nterior occlusion displacing the wer right central cisor labially and here is an sociated ehiscence g The same tient as in Fig 6, t the cross bite s been corrected th a removable pliance and ere has been improvement the gingival ndition vidual will receive from this will depend on the severity of the presenting malocclusion as well as the patients own perception of the problem Some individuals can have a marked degree of dento-facial deformity and be unconcerned with their appearance Although a practitioner may suggest treatment for such an individual, patients should not be talked into treatment and must be left to make the final decision themselves Mild malocclusions should be treated with caution Not only will the net improvement in the appearance of the teeth be small, but also as nearly all teeth move to some degree after orthodontic treatment the risk of relapse in these cases is high Whilst minor movements after the correction of severe malocclusions still produce spontaneously andwill no long-term problems usua substantialally netdevelop overall improvement for the patients, the same is not true of can minor problems cause stripDeep overbites occasionally Many practitioners will have encountered the in Figure 8a ping of the soft tissues as shown parent who can spot a 5-degree rotation of an and b This is a case where there is little aesupper lateral incisor from fifty metres and but is conthetic need for treatment because of the vinced this will be the social there death is of their child damage to deep overbite substantial Regardless ofthe howsoft insistent the Clearly parent orifchild tissues this is,is allowed to the practitioner should approach such problems continue there is a risk of early loss of the lower incisors that would produce a difficult Table Index of Treatment Need restorative problem Dental health component spontaneously and no long-term problems usually develop Deep overbites can occasionally cause stripping of the soft tissues as shown in Figure 8a and b This is a case where there is little aesthetic need for treatment but because of the deep overbite there is substantial damage to the soft tissues Clearly if this is allowed to continue there is a risk of early loss of the lower incisors that would produce a difficult restorative problem Treatment need WHO SHOULD BE TREATED? No need Dental irregularity alone is not an indication for Little need treatment Most orthodontic treatment is carried Moderate need out for aesthetic reasons and the benefit an indi- Aesthetic component Table Index of Treatment Need Dental health component Treatment need No need Little need Moderate need Great need Very great need Aesthetic component 10 be advised of this prior to the commencement of treatment Once the incisors are decompensated and the arches co-ordinated the patient is ready for surgery The maxilla was advanced mm and the mandible set back by mm, producing an overall change of 13 mm in the skeletal relationship In addition, because the patient had a facial asymmetry, the mandible was rotated in order to correct this As dentistry becomes increasingly sophisticated with more treatment options available than ever before, no single specialty in dentistry can work alone to provide the full range of treatment options Some of the most interesting aspects of orthodontic treatment come from LỆCH LẠC THEO CHIỀU ĐỨNG working in a combined approach with one’s colleagues and it is important to recognize and respect the skills of other disciplines Work of this nature can be amongst the most satisfying both for the clinician and the patient The authors thank Paul Cook for the use of figures 5(a-d) Andreasen J O, Andreasen F Textbook and color atlas of traumatic injuries to the teeth 3rd ed pp671-690 Munksgaard, Copenhagen: Mosby, 1994 Davies S J, Gray R M J, Sandler P J, O'Brien K D O Orthodontics and occlusion Br Dent J 2001; 191: 539-549 Kim Y H Anterior openbite and its treatment with multiloop edgewise archwire Angle Orthod 1987; 57: 290-321 Sandy J R, Irvine G H, Leach A Update on orthognathic surgery Dent Update 2001; 28: 337-345 Guest Leaders Guest leaders in the BDJ are there to provide an opportunity for anyone involved dentistry (including patients) to write an appropriate comment for publication The are published to accompany the usual Leader from the Editor Submissions must be between 200 and 500 words, typed and double-space Name, address and telephone number should be supplied, as well as your position the dental world For further help and guidance, please contact: The Editor, British Dental Journal, 64 Wimpole Street, London W1G 8YS or E-mail: k.maynard@bda.org Treatment need Little need BRITISH DENTAL JOURNAL VOLUME 196 NO APRIL 24 2004 Moderate need Great need Great need Very great need Treatment need Little need Moderate need WHO SHOULD BE TREATED? Dental irregularity alone is not an indication for Great need treatment Most orthodontic treatment is carried Fig 8a This malocclusion10has an extremely deep bite which out for aesthetic reasons and the benefit an indican be associated with potential periodontal problems 436 Fig 8a This malocclusion has an extremely deep bite which can be associated with potential periodontal problems vidual will receive from this will depend on the severity of the presenting malocclusion as well as the patients own perception of the problem Some individuals can have a marked degree of dento-facial deformity and be unconcerned with their appearance Although a practitioner may suggest treatment for such an individual, patients should not be talked into treatment and must be left to make the final decision themselves Mild malocclusions should be treated with caution Not only will the net improvement in the appearance of the teeth be small, but also as nearly all teeth move to some degree after orthodontic treatment the risk of relapse in these cases is high Whilst minor movements after the correction of severe malocclusions will still produce a substantial net overall improvement for the patients, the same is not true of minor problems Many practitioners will have encountered the parent who can spot a 5-degree rotation of an upper lateral incisor from fifty metres and is convinced this will be the social death of their child Regardless of how insistent the parent or child is, the practitioner should approach such problems Fig 8d At the completion of orthodontic treatment the teeth were restored with composite Fig 8b The same patient as in Fig 8a, but not in occlusion The deep bite has resulted in labial stripping of the periodontium on the lower right central incisor BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 Fig 8b The same patient as in Fig 8a, but not in occlusion The deep bite has resulted in labial stripping of the periodontium on the lower right central incisor BRITISH DENTAL JOURNAL VOLUME 195 NO OCTOBER 25 2003 10 5/5/16 Khớp cắn sâu Khớp cắn hở 11 5/5/16 12 ... số La mã – I, II III 5/5/16 Phân loại lệch lạc khớp cắn theo Angle n  Lệch lạc khớp cắn loại I Tương quan khớp cắn vùng hàm lớn thứ bình thường đường khớp cắn không mọc khơng vị trí, xoay ngun... mọc chen chúc 5/5/16 Lệch lạc khớp cắn loại II n  Đỉnh múi gần hàm lớn thứ hàm phía gần so với rãnh hàm lớn thứ hàm 5/5/16 Lệch lạc khớp cắn loại III n  Lệch lạc khớp cắn loại III Đỉnh múi...5/5/16 ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN ẢNH HƯỞNG CỦA LỆCH LẠC KHỚP CẮN Chấn thương Bệnh miệng: Chấn thương Bệnh miệng: Những trường hợp khớp cắn sâu mà cửa HD tiếp xúc với vòm miệng