Complex non skeletal proplems.pptx orthodontics

Complex non skeletal proplems.pptx orthodontics

1. Complex Nonskeletal Proplems in Preadolescent Children: Preventive and Interceptive Treatment. By Mohamed Fahmy Alshora BDS 2018, Faculty of Dental Medicine, Al- Azher University ( Boys,Cairo )

2. OUTLINE

3.   Eruption Problems  - Delayed Incisor Eruption If there is no impediment such as supernumerary tooth or other pathology -> simple excision of the overlying soft tissue . Butoon or bracket + elastomeric chain or NiTi overlay wire .

4. - Transposition - Rare positional interchange of two adjacent teeth. - Most likely are mandibular incisors and maxillary premolars – often as a consequence of ectopic eruption. Treatment of transpositions involving the maxillary canine if not addressed early is quite challenging – moving the teeth to their natural positions can be difficult because this requires bodily repositioning, translating the canine facially or lingually past the other tooth .

5.  Primary Failure of Eruption – PFE  - Characterized by failure of eruption of permanent posterior teeth when there is no mechanical interference. - Have genetic etiology. - Noted in late mixed dentiton .  Affected teeth are not ankylosed but do not erupt and do not respond normally to ortho force. Prosthetic replacement of the teeth that failed to erupt, possibly segmental osteotomies or distraction osteogenesis is almost the only treatment – only in mild cases!

6.  Impact of Radiation Therapy and Bisphosphonates - Stem cell transplantation -SCT and total body irradiation – TBI. - Early age at SCT is more of a risk factor than TBI (<5 y.o .) - Result of high-dose chemotherapy and TBI – shortened roots; especially in the group of 3-5 y.o . - Irradiated teeth fail to develop, others fail to erupt, some may erupt even though they have extremely limited root development .

7. Bisphosphonates in conjunction with other therapies; steroid-induced osteoporosis or osteogenesis imperfects -> make sortho tooth movement almost impossible. >> Treatment should not be attempted while bisphosphonates are actively being used. Intravenous treatments appear to produce more long-term impact than oral medication.

8. Trumatic displacment of teeth - Immediately after traumatic injury -> repositioned with finger pressure to a near normal position and out of occlusal interference -> stabilized with light wire or nylon filament for 3-5 weeks; exhibit physiologic mobility.  - If alveolus has been fractures -> stabilized with heavy wire for approx. 6 weeks. - Wait 3-4 months to begin active treatment; for sever periodontal-type injuries ( luxation , intrusion, extrusion or avulsion)– up to 1 year. - Devitalization is likely for those who have severe periodontal trauma.

9. - Teeth with incomplete apex, intruded more than 7mm and those with complete roots intruded more than 3mm ->> unlikely achieve complete correction with only ortho ->> surgical repositioning should be considered before healing from trauma is complete. - Periodontal injury can lead to ankylosis . - Intrusion -> we wait 3 weeks only if we have active re-eruption, if not, intervention is needed earlier.  - Decoronation . - If traumatically extruded -> do not intrude.

10.   Ankylosed Primary Molars Without Successors - If the premolar is blocked by the retained crown of ankylosed primary molar, the remainder of the crown should be extracted.  - Early extraction of ankylosed second primary molar before vertical defect and not placing space maintainer.  - Decoronation , in patients who still have the growth of spurt remaining.

11.  Space-Related Problems - Lack of adequate space for alignment of permanent incisors. - Loss of space due to mesial drift of permanent molars. Major indication for treatment in the early mixed dentition.

12.   EXCESS SPACE    Spacing of Permanent teeth Absence of incisor protrusion – excess space is not frequent . Small teeth in normal-sized arches or normal-sized teeth in large arches. Allow eruption of the remaining permanent teeth before closing the space. No advantage to early treatment unless it is for compelling esthetic reasons.

13. Midline diastema often is localized excess space problem – mesial crown and root movement provides more space for eruption of the lateral incisors and canines. Diastema closure is more predictable if only MESIODISTAL movement is required. Frenectomy after space closure and retention may be necessary; frenectomy before treatment is contraindicated . 

14.   Maxillary Dental Protrusion and Spacing  Treatment in early mixed dentition is indicated only when maxillary incisors protrude with spaces between them and are esthetically objectionable or in danger of traumatic dental injury (TDI).   No skeletal discrepancies, prolonged finger-sucking habit – eliminating habit before tooth movement. Class II malocclusion with often skeletal component ->> treatment must address larger problem.

15.   Bodily movement ->> archwire with bands on first molars, brackets on incisors, retracting and space-closing force –closing loops; rectangular archwire must be used ->> Headgear or Nance appliance for additional anchorage. If overbite is deep – add biteplate that allows eruption of posterior teeth.

16.   Missing Permanent Teeth Thorough evaluation to determine correct treatment.  Profile, incisor position, tooth color, shape, skeletal and dental development or position, space availability or deficiency can be crucial in treatment planning.

17.   Missing Second Premolars If patient has acceptable occlusion, maintaining primary second molars is reasonable plan, many can be retained at least until the patient reaches early 20s. Reduction of their mesiodistal width is often needed to improve interdigitation of the posterior teeth, but if this is done,risk of resorption of mesiodistal diverging roots of primary molar when they contact adjacent permanent tooth roots.

18. Keeping primary molar as long as possible is excellent way to maintain alveolar bone in that area.   If the space, profile, jaw relationships are good or somewhat protrusive -> extract primary second molars that have no successor at age 7-9y and allow first molars to drift mesially .  TADs to facilitate unilateral space closure are not indicated before 12 years of age!. ( in case of only one primary molar is missing ). Hemisectioning of the primary tooth and pulp therapy.

19.   Missing Maxillary Lateral Incisors Long term retention is almost never an acceptable plan. Erupting permanent canine resorbs primary lateral incisor and spontaneously subsitiutes for the missing lateral incisor,which means that primary canine has no successor and is sometimes retained.  If canine moves into the place of lateral ->> ultimate treatment is substitution of canine or opening space but the canine generates the formation of alveolar bone. Space closure is usually avoided when patients have a class III tendency.

20.   Autotransplantation Possible solution when there is missing tooth but crowding in another.  Transplanted tooth has approx. 2/3 to 3/4 of its root formed – decision needs to be made during mixed dentition. Move premolar into the location of missing maxillary incisors or replace missing first molar with third molars. 3 months of healing, followed by light ortho forces to achieve final tooth position and restorative treatment to recontour the crown of the transplanted tooth.

21.   Localized Moderate-to-Severe Crowding  Localized crowding (>3mm) -> in posterior quadrant the result of severe space loss after early loss of primary molar orectopic eruption. In anterior portion – most common localized problem is shift of mandibular dental midline. If we have space problems and midline problems – it needs to be addressed before the canines erupt -> supportive lingual arch and coil spring.

22. Generalized Moderate and Severe Crowding --  Expansion VS Extraction in Mixed Dentition Treatment  Moderate space deficiency – generalized but not severe crowding of the incisors Potentially severe crowding usually is obvious in the primary dentition, even before a space analysis can be completed  Severe crowding -> limited mixed dentition treatment will not be sufficient and extraction has to be considered 

23. Expansion for Treatment of Crowding in the Early Mixed Dentition Some facial movement of the incisors and expansion can be accommodated if: a) lower incisor position is normal or somewhat retrusive. b) lips are normal or retrusive. c) overjet is adequate. d) overbite is not excessive. e) good keratinized tissue facial to the lower incisors.

24. Early expansion can involve any combination of several possibilities a) maxillary dental or skeletal expansion. b) mandibular buccal segment expansion by facial movement of the teeth. c) advancement of the incisors and distal movement of the molars in either arch. Faciolingual irregularity will resolve if space is available but rotational irregularity will not.

25.  Expansion for Crowding in the Late Mixed Dentition: Molar  distalization In late mixed dentition – to obtain space by repositioning molars distally  Intraoral appliances for distal molar movement will be accompanied – indications a) less than 4-5mm of space per side, with some tipping of molars acceptable. b) erupted maxillary anterior teeth and first premolars (ideally) – anchorage. c) normal or retrusive lip, maxillary dental position – 1/3 of movement is facial tipping d) overjet limited.  e) vertical face dimension – normal or short-faced – distal movement of molars can open the bite.  f) overbite – greater than normal. 

26. - Headgear - +simplicity -good patient compliance; min. 12-14 hours per day, 400gm of force per side, tooth move 1mm per month so 3-5 months to obtain 3mm of correction with good cooperation - Short term duration – cervical or high-pull headgear  - If bodily distal movement and there is adequate anterior teeth for anchorage, anterior incisor movement can be tolerated, overbite adequate – other appliances can be considered ex. Pendulum. - TAD-supported molar distalizing appliances – in children above 12 years of age.

27.     Early (Serial) Extraction - Severe crowding, decision can be made during early mixed dentition period that expansion is not advisable. - Timed extraction of primary and ultimately permanent teeth to relieve severe crowding. - When no skeletal problem exists. - Space discrepancy is large – greater than 10mm per arch.

28.   - If initial space discrepancy is smaller – more residual space must be anticipated – to compensate for moderate skeletalclass II and class III problems ( class II – upper extractions; class III lower extractions). - Extraction of primary incisors if necessary, then primary canines; the goal is to influence permanent first premolars to erupt ahead of the canines so that they can be extracted and canines can move distally into this space. - Enucleation – at the same time extraction of primary and permanent; better avoided because can leave bone defect if done too early. 

29. The Borderline Crowding Case: What Do You Do? Unless crowding is severe, maintaining leeway space during the last part of the transition to the permanent dentition increases the chance of successful non-extraction treatment.