DEEP BITE \ VERTICAL PLANE DISCREPANCIES .pptx

A PRESENTATION ABOUT DENTAL DEEP BITE DISSCUSSION THE DEFINITION ,CLASSIFICATION,ETIOLOGY AND MAMAGEMENT .

1. Vertical Plane Discrepancies Deep Bite By : dr mohaMMED ALMOOSAWI

2. Deep Bite According to Graber, deep bite is defined as ‘a condition of excessive overbite, where the vertical measurement between maxillary and mandibular incisal margins is excessive when mandible is brought into habitual or centric occlusion’. Deep bite may be complete overbite or incomplete overbite and may be dental or skeletal in origin. Normal incisor overbite refers to the maxillary incisors overlapping the mandibular incisors by 2–4 mm vertically, or one-third to one-half of their crown height, when the opposing posterior teeth are in contact in centric occlusion. Overbite is described as: • Increased, if the maxillary incisors overlap the mandibular incisor crowns vertically by greater than one-half of the lower incisor crown height; • Decreased, if the maxillary incisors overlap the mandibular incisors by less than one third of the lower incisor crown height. If there is no vertical overlap between the anterior teeth, this is described as an anterior open bite and a measurement should be made of the incisor separation.

3. CLASSIFICATION I. Deep bite can be classified into the following two types: 1. Incomplete overbite 2. Complete overbite.

4. CLASSIFICATION Incomplete Overbite Incomplete overbite is an incisor relationship in which the lower incisors fail to occlude with either the upper incisors or the mucosa of the palate when teeth are occluded.

5. CLASSIFICATION Complete overbite is an incisor relationship in which lower incisors contacts the palatal surface of the upper incisors or the palatal tissue when the teeth are in centric occlusion

6. CLASSIFICATION If the overbite is complete to the gingival tissues, it is described as traumatic if there is evidence of damage. This is most commonly seen on the palatal aspect of the upper incisors or labial aspect of the lower incisors (e.g. inflammation, bleeding, recession). Traumatic deepbite : in which the deepbite associated with the Impingement of the mandibular incisors in the mucosa palatal to the maxillary incisors commonly is seen in malocclusions with extremely deep bite as in sever Class II malocclusion. Bi-traumatic deepbite : usually seen in some Class II, Division 2 malocclusions with minimal overjet, the retroclined maxillary incisors may impinge in the keratinized tissue labial to the mandibular incisors, causing gingival recession at the same time there is a trauma to palatal mucosa caused by lower incisors.

7. CLASSIFICATION II. Deep bite can further be classified into the following two types: 1. Dental deep bite 2. Skeletal deep bite

8. CLASSIFICATION Dental Deep Bite Dental deep bite is confined to the dentition where there is extrusion of anterior and intrusion of molars. Dental deep bite is often seen in Angle’s class II division 2 malocclusion.

9. CLASSIFICATION Skeletal Deep Bite Skeletal deep bites are usually of genetic origin caused by upward and forward rotations, i.e. counterclockwise rotation of the mandible . It can also be caused by clockwise rotation of maxilla or a combination of both . Skeletal deep bites are seen in Angle’s skeletal class II division 2 malocclusion

10. Factors Affecting the Development of Deep Overbite Discrepancies in the size and/or position of the jaws can adversely affect the normal vertical development, resulting in a deep bite malocclusion. Mandibular growth rotations play an important part in the etiology of some malocclusions, as well as the stability of the result. A marked forward growth rotation tends to result in reduced anterior facial proportions and an increased overbite, while marked backward rotations tend to result in an increased anterior vertical facial height and a reduced overbite (or anterior open bite).

11. Factors Affecting the Development of Deep Overbite

12. Factors Affecting the Development of Deep Overbite

13. The development of the vertical dimension is also affected by the equilibrium between the tongue, lips, cheeks, and opposing dentition on the developing dento -facial complex. This equilibrium of the biologic system is determined more by the duration than the magnitude of a force. The occlusal forces of teeth serve to maintain equilibrium in the vertical dimension of the orofacial complex, but pathologic (parafunctional) habits such as clenching, bruxism, or hyperactive muscles of mastication have the potential to influence the vertical equilibrium. This may result in the incomplete eruption of posterior teeth and a decreased vertical development of the posterior maxillary and mandibular alveolar processes producing an increased anterior overbite. Factors Affecting the Development of Deep Overbite

14. Dental Features of Deep Bite The dental arches tend to be short, wide and mildly crowded with deep overbite. The lower labial segment is often retroclined with an increased (exaggerated) curve of Spee as a result of the lower incisors over-erupting due to the lack of occlusal contact with the maxillary incisors. Increased overbite. Decreased overjet . Extruded maxillary anteriors . Intruded maxillary posteriors. Increased susceptibility to food impaction and resultant gingivitis in lower anterior region.

15. Soft Tissue Features Acute nasolabial angle, deep mentolabial sulcus with prominent Pogonion. The retroclination of the lower anterior teeth can result in lack of support for the lip, which relative to the chin and nose appears retrusive.

16. Ceph /Skeletal Features Palatal, occlusal, and mandibular planes, which run almost parallel, lead to a low (flat) mandibular plane angle. The mandible shows upward and forward rotation in Individuals with this condition, who tend to have a longer ramus (increased posterior facial height), a nearly right-angle or acute gonial angle, and reduced anterior lower facial height.

17. TREATMENT Management of deep bites can be brought about by maxillary anterior intrusion, maxillary posterior extrusion, mandibular anterior intrusion, mandibular posterior extrusion or combination of these . Depending upon the specific problems and treatment objectives for an individual patient, any or all of these above tooth movements may be used for deep bite management. Light forces are used for incisors intrusion (recommended forces for lower incisors intrusion are in the range of 12.5 g/tooth and for maxillary incisors about 15–20 g/ tooth) whereas heavier forces for extrusion of posteriors. Deep bite can be treated by using removable, myofunctional appliances or fixed orthodontic appliances.

18. REMOVABLE ORTHODONTIC APPLIANCES TO CORRECT DEEP BITE Anterior bite plane can effectively be used to treat deep bite. It is often used in conjunction with fixed mechanotherapy to treat deep bite along with other malrelations of teeth. Anterior bite plane is a modified version of Hawley’s removable orthodontic appliance with the following features: 1. Adam’s clasps on molars—aid in retention of the bite plane. 2. Labial bow—prevents maxillary anterior proclination . 3. Bite plane should be—1.5–2.0 mm.

19. Flat Anterior Bite Plane The flat anterior bite plane is used with maxillary removable orthodontic appliance and is made by building up of acrylic base material behind the maxillary incisors so that the mandibular incisors touch the bite plane before the buccal teeth come into occlusion . The main purpose of flat anterior bite plane is to reduce the incisal overbite (deep bite). It is mainly used to reduce incisal overbite in Angle’s class II division 2 malocclusion and Angle’s class I malocclusion with deep bite.

20. Mode of Action of Flat Anterior Bite Plane The flat anterior bite plane induces extrusion of upper and lower posteriors thereby it brings about reduction of the incisal overbite (deep bite). Flat Anterior Bite Plane

21. Inclined Anterior Bite Plane Inclined anterior bite plane on the maxillary removable orthodontic appliance is also used for the correction of deep bite cases. It is mainly used in the correction of deep bite in Angle’s class II division 1 malocclusion. Mode of Action of Inclined Anterior Bite Plane The inclined anterior bite plane induces a forward mandibular posture and reciprocal backward force on the maxillary appliance from the masticatory forces and extrusion of lower posteriors.

22. MYOFUNCTIONAL ORTHODONTIC APPLIANCE TO CORRECT DEEP BITE Thin layer activation (TLA) following myofunctional orthodontic appliances, such as activator can be used for correction of deep bite. In both the appliances interocclusal acrylic is trimmed to facilitate extrusion of posteriors followed by intrusion of anteriors . Bionator or Frankel appliance (FR Ia ) can also be used for the management of deep bite cases.

23. MYOFUNCTIONAL ORTHODONTIC APPLIANCE TO CORRECT DEEP BITE

24. FIXED ORTHODONTIC TREATMENT APPLIANCE TO CORRECT DEEP BITE Fixed orthodontic appliances can be used to treat deep bites. The intrusion arches and utility arches when used bring about correction of deep bites by intrusion of incisors and are indicated in patients with excessive maxillary incisor visibility at rest or when smiling (gummy smiles).

25. FIXED ORTHODONTIC APPLIANCE WITH UTILITY ARCHES Utility arches are arch wires used with fixed orthodontic appliance for the correction of deep bite cases. They are bent in such a way that they bypass the premolars and are engaged on the incisors. These arch wires can be used to perform a number of tooth movements including incisors protrusion or retraction, intrusions of incisors . They are activated by giving a V bend in the buccal segment of the wire mesial to molar to generate an intrusive force on the incisors.

26. FIXED ORTHODONTIC APPLIANCE WITH UTILITY ARCHES

27. FIXED ORTHODONTIC APPLIANCE WITH UTILITY ARCHES

28. ARCH WIRES WITH REVERSE CURVE OF SPEE The use of arch wires with reverse curve of Spee is another common approach to the management of deep bite. These arch wires provide both an intrusive force on the anterior teeth and an eruptive force on the posterior teeth .

29. USE OF ANCHORAGE BENDS Anchorage bends are given in the arch wire mesial to the molar tubes so that the anterior part of the wire lies gingival to the bracket slot . Thus, when these wires are pulled occlusally and engaged into the brackets, a gingivally directed intrusive force is exerted on the incisors which reduce the deep bite.

30. RETENTION FOLLOWED BY DEEP BITE CORRECTION If the deep bites are corrected by intrusion of maxillary anteriors then a bite plate on maxillary retainers is desirable. The patient is instructed to wear such retainer continuously for the period of minimum 4–6 months. In deep bite cases, overcorrection is usually desirable, and equilibration and adjustment to functional occlusion are necessary.

31. REFERENCE 1. an introduction to orthodontics by Simon J. Littlewood and Loura Mitchell fifth edition 2. ORTHODONTICS Principles and Practice by Basavaraj Subhashchandra Phulari second edition 3. Baghdad university lectures