Overlay Denture 1

Dr. Mahmoud Ramadan

Rem. Prosthodontics 502

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Dr. Mahmoud Ramadan

Overlay Denture -:Advantages* Superior method of treatment of certain cases as congenital defects.-1 .(E.g. (cleft palate, class III pt's& pt's have few remaining teeth .Simplicity of construction: as those for conventional complete denture-2 Ease of maintenance: (repairs, alteration or refitting of over-denture)-3 .as those for conventional complete denture .stability as in fixed& complete dentures ↑-4 .retention because, of ↑ stability of over-denture ↑-5 .esthetics: due to restoring bony defects & selection of teeth freely ↑-6 .Open (roofless) palate is possible when anterior& posterior are saved-7 .Reasonable cost: ↓ than fixed partial denture-8 .familiar procedure: no special training should be required-9 Ease in making measurements: the vertical dimension of occlusion-10 maintained with high degree of accuracy – stabilization of the recording .bases .Ideal occlusion: the occlusion is acceptable esthetically-11 Excellent pt. acceptance: because, loss of all teeth at an advanced age,-12 .more traumatic to the pt .trauma to supporting structure: ↓ resorption of alveolar ridge ↓-13 Stabilisation& support of existing structures: vertical dimension of-14 .occlusion is maintained and lip& face support is maintained .Minimal adjustment: because, of ↑ stability& support-15 Possibility of using attachments( ↑ retention )& soft liners( when it is-16 .( difficult to maintain a seal Transitional (training) denture: for preparing to receive complete-17 .denture Conversion to complete denture: loss of one or all retainable teeth-18 .corrected by relining& rebasing .Reversibility-19 Ease of cleaning: being removable →easier to clean than fixed partial-20 .denture

-:Disadvantages* .(expensive than conventional complete denture(endo- perio- surgery ↑-1

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Dr. Mahmoud Ramadan .Bulker than fixed partial denture or removable partial denture-2 .Some prefer fixed partial dentures& don't like removable dentures-3 .Caries& periodontal diseases can progress in pt's with↓oral hygiene-4

-:Indications* .Presence of few remaining teeth -1 .Pt's with only one root or tooth remaining -2 .Pt's with poor prognosis for complete dentures -3 .Pt's with class II & IV Angle classification -4 .Pt's with abnormal jaw size or bony defects -5 .(Pt's with congenital defects (cleft palate or microdontia -6 .(periodontal health of teeth (↓ crown-root ratio ↓ mobility ↓ -7

-:Contraindications* .Poor oral hygiene -1 .(Low inter-arch space (can't accept the denture& the abutments -2 .Grade II mobility of teeth -3

Examination, Diagnosis, Treatment planning& Prognosis -:A)History & Records -:I [ Medical history [

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Dr. Mahmoud Ramadan .ve ) correlation between emotional state& denture problems + ) → .Debilitating medical or psychiatric disorders → .Pt. ability to maintain an adequate level of oral hygiene →

-:II [ Dental history [ Past dental history gives information about previous experiences → .which may influence his attitude, motivation& expectation Why did the pt. loose teeth& what difficulties did he have with → ?replacements Pt. should be formed about expectations within treatment capabilities → .to avoid disappointment Pt. with acceptable oral hygiene have much better over-denture → .prognosis than those of bad oral hygiene

-:III [ Pretreatment records [ Accurate diagnostic casts mounted in a suitable articulator which -1 .supply information about the pt.& selection of the abutments .Color transparences or photographs -2 .Cephalometric radiographs -3

-:B)Examination

-:Visual& Digital Examination ♥ -:a- Visual Examination Lips, buccal Mucosal, gingiva, floor of the mouth, hard& soft palate → .should be examined .Possible pathologic changes should be evaluated → Evaluation the response of supporting tissues to existing prosthesis, → .such as inflammation or hyper plastic tissue

-:b- Digital Examination Exostosis, sharp mylohyoid ridges, displaceable tuberosity tissue, → displaceable tissues on the residual ridges, tissue undercut areas in need .for surgical correction

-:Dental Examination ♥

.Carious lesions& defective restorations -1

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Dr. Mahmoud Ramadan .Vitality tests -2 .Missing teeth -3 .Condition of replacements -4 .Occlusion -5 .Adequate denture space -6 .Clenching or Bruxism -7 .Abnormal tongue or lip habit -8 .Oral hygiene status -9 .Pt. denture cleaning methods -10

-:Periodontal Examination ♥

-:Diagnosis of → .Signs& symptoms of chronic periodontal disease -1 .Generalized bone loss -2 .Increased periodontal pocket depth -3 .Hyper-mobility -4 .Crevicular& pocket depths as well as furcation should be probed -5 .Teeth with horizontal& Vertical displacement are poor choice -6 It is essential to evaluate the pt. oral hygiene in relation to the → .periodontal status Maintaining an adequate oral hygiene is important in achieving a → .reasonable service life for the overlay denture

-:Radiographic Examination ♥

Individual periapical films supplemented by a panoramic radiograph → -:should be adequate. Also we should observe .Retained roots -1 .Impacted teeth -2 .Crown-Root ratio -3 .Carious lesions -4 .Status of previous endodontic treatment -5 .Radiolucent& radiopaque lesions of the jaw -6 .Status of periodontium -7

-:C) Treatment Planning

-:Indications for Fixed Partial Denture *

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Dr. Mahmoud Ramadan .Properly distributed& healthy teeth to serve as abutments -1 Teeth have suitable crown-root ratio after radiographs, diagnostic -2 .cast& oral examinations

-:Indications for Removable Partial Denture * .Distal extension situations -1 .After recent extraction -2 .Long edentulous span -3 .Need for bilateral bracing -4 .Esthetics in anterior region -5 .Excessive loss of residual bone -6

-:Indications for Removable Complete Denture * .Uncooperative& disinterested pt -1 .No retainable teeth are present -2

-:Indications for Overlay Denture * .or fewer retainable teeth are present in an arch 4 -1 .Pt. loose teeth in one arch& the other remain dentulous -2 .Unfavorable tongue position or improper muscle attachment -3 Any situation in which stability& retention would be a very serious -4 .problem with complete denture

-:Types of Overdenture ♥ -:Immediate Overdenture (1 Constructed for insertion immediately after removal of some natural → .teeth .Used when pt. has many hopeless teeth → The abutment teeth are selected, treated and then, Overdenture is → .inserted .This type is modified as required& can be worn for several years →

-:Transitional Overdenture (2 Obtained by converting an existing Removable Partial Denture to → .Overdenture status

-:Remote Overdenture (3

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Dr. Mahmoud Ramadan Constructed for insertion at time remote from removal of hopeless → .natural teeth Complete or Partial Overdentures with metal or acrylic bases can be → .fabricated

-:Abutment Selection ♥

-:The abutments should be evaluated from the view of points →

-:a) Periodontal Status Teeth must have acceptable state of periodontal health prior to * .completion of the Overdenture -:Basis for selection → .Acceptable state of periodontal health -1 .Use teeth that less than ideal -2 .Teeth with minimal mobility -3 .Adequate bone support -4 .Accept periodontal treatment -5 .Good crown-root ratio -6

-:b) Caries activity Teeth with minimal or no caries involvement should be selected for → .abutments .Carious teeth can be selected after successful restorative procedure → .Caries in unprotected abutments can lead to failure of the restoration →

-:c) Potential for Endodontic treatment .Recommended for Overdenture abutments * .It's advantages overcome it's disadvantages * -:Successful Endodontic treatment contributes to → .Esthetics: by allowing sufficient reduction of the abutment tooth -1 .Crown-root ratio: improved by crown reduction -2 Permits using of: tilted or malposed or hemi-sectioned teeth as -3 .abutments for Overdenture

-:d) Positional consideration Overdentures should be considered with 4 or fewer retainable teeth → .((which have less than ideal periodontal support -:Depending on distribution * -:abutments in one arch 4 ♥

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Dr. Mahmoud Ramadan Represent an ideal stress distribution. E.g. (2 Canines& 2 second → .(premolars -:Factors affecting support in Overdenture → .Number of the abutments -1 .Distribution of the abutments -2 .Position of the abutments -3 -:abutments in one arch 3 ♥ abutments are in one side of the arch& one is on the other side, will 2 → .give unbalanced support .canines& one central incisor (tripod), will give better distribution 2 → -:abutments in one arch 2 ♥ Canines& premolars are selected more than any other type of teeth. → -:Because, they are .Amenable to endodontic treatment -1 .Adequate periodontal attachment area -2 .Strategic positions in the arch -3 .The 2 abutments should be situated bilaterally for optimum support → Anterior positioning of the canines minimize the soft tissue loading in → .anterior arch -:Good results gained when abutments aren't approximating ♥ Canine& approximating premolar don't give much more support than -1 .one abutment .Approximating abutments are difficult to clean -2 Approximating abutments make positioning of teeth in Overdenture -3 .more difficult

-:e) Occlusal consideration It is essential to consider occlusion in selecting abutments for → -:Overdenture If an Overdenture is opposed by Removable Complete or Partial -1 Denture the forces will be less than if the Overdenture is opposed by .intact natural dentition Abutments for Overdentures opposed by a natural dentition should be -2 .selected to reflected the high need for support& stability

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Dr. Mahmoud Ramadan -:D)Prognosis

.Accurate examination& diagnosis affect prognosis of Overdenture -1 .Oral hygiene level of the pt -2 .Clinical& laboratory procedures -3 .Post-insertion service& maintenance -4

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