Tugas Kuliah Implant .txt

8/14/2019 Tugas Kuliah Implant .txt

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Socket preservationSocket preservation is a relatively new term in implantdentistry, which implies the placement of variousimplantable materials within extraction sockets tomaintain the socket anatomy. To date, there isinconclusive evidence that this procedure maintainsthe original socket dimensions. In contrast, evidenceexists that placement of foreign materials intoextraction sockets may interfere with normal boneformation (6, 8). Iasella et al. (36) compared normalsocket healing with those grafted with demineralizedfreeze-dried bone and covered with a collagen barriermembrane. Unaugmented sockets decreased in widthby an average of 1.7 mm, while grafted sites decreasedby 1.2 mm (a difference of 0.5 mm). The quantity ofbone observed on histological analysis was slightlygreater in preservation sites, although these sites includedboth vital and nonvital bone. Other researchershave compared alveolar ridge dimensions andhistological characteristics of ridges preserved withtwo different graft materials (83). Twenty-four subjects,each requiring a nonmolar extraction and delayedimplant placement, were randomly selected toreceive ridge preservation treatment with either an

allograft in an experimental putty carrier plus a calciumsulfate barrier, or a bovine-derived xenograftplus a collagen membrane. Horizontal and verticalridge dimensions were determined using a digitalcaliper and a template. At 4 months post-extraction, atrephine core of bone was obtained for histologicalanalysis. Allograft mixed with an experimental puttycarrier produced significantly more vital bone fill thandid the use of a xenograft with no carrier material.Ridge width and height dimensions were similarlypreserved with both graft materials.There is evidence that resorbable barriers, withoutconcomitant grafting, reduce alveolar ridge resorption

after tooth extraction (45, 85). Following elevation ofbuccal and lingual full-thickness flaps and extractionof teeth, experimental sites were covered with bioabsorbablemembranes; control sites received nobarrier membrane. Titanium pins served as fixed referencepoints for measurements. Flaps were advancedto achieve primary closure of the surgical wound, andno membrane exposure occurred during the course ofhealing. Re-entry surgery performed after 6 monthsshowed that experimental sites presented with significantlyless loss of alveolar bone height, more internalsocket bone fill, and less horizontal resorption of thealveolar bone ridge. This study suggests that treatment

of extraction sockets with membranes made of glycolideand lactide polymers is of value in preservingalveolar bone in extraction sockets and preventingalveolar ridge defects. Use of barrier membranes maybe indicated to minimize crestal alveolar boneresorption in cases where dental implants are not partof the treatment plan. However, placement of implantsinto membrane-treated sites may cause limitedosseointegration as the result of formation of suboptimalbone. Until there is sufficient evidence that


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barrier membranes can maintain socket anatomywithout interfering with osseointegration, cautionshould be exercised when using such treatment inimplant dentistry.84Becker & GoldsteinSoft tissue management forimmediate implantsPrimary flap closure over immediately placed implantswas considered important for many years (4,22, 31). The discrepancy of size and form between theextraction socket and an immediate implant ensuresthat a space usually exists around the coronal portionof the implant. Frequently, pre-existing bony defectscan also be found in the extraction area. Dependingon size, the bony defects may be treated withregenerative techniques (5, 49). Soft tissue coverageof the implant area was considered necessary toachieve bone fill adjacent to the implant. The presenceof interdental bone, soft tissue anatomy, smileline, occlusion, and interdental space are all importantfactors in the placement of immediate implantsin the esthetic zone (30, 39, 47, 66, 74).Various surgical techniques have been proposed to

achieve primary soft tissue closure with immediateimplants (4, 70, 71, 73). Use of a rotated buccal flap(A) (B)(C) (D)(E) (F)Fig. 3. (A) Maxillary second bicuspid with a verticalfracture (arrow) and buccal dehiscence. (B) A machinedsurfaceimplant has been installed in the osteotomy.There were 13 threads exposed and the implant was stable.(C) A collagen membrane has been adapted over theallograft and implant site. (D) A pedicle flap has beenrotated from the palate and sutured over the implant andgrafted site. (E) At 6 months the implant was uncovered

and the final restoration was placed. There is slight marginalinflammation. (F) Radiograph taken after 6 monthsof healing and before final restoration.85Immediate implant placementfrom an adjacent tooth can be used to achieve closureover implants placed at the time of extraction.This procedure can be applied for single or multipleimplant sites and can be employed in conjunctionwith membrane barriers or various grafting materials.The main disadvantage of this technique is therequirement for an adequate width of keratinizedmucosa and vestibule depth. Edel (27) was the first

to publish on the use of a connective tissue graft forcoverage of immediately placed implants. A potentialproblem is the limitation of donor tissue size. Inperiodontal plastic surgery, an acellular dermalmatrix allograft is sometimes employed as an alternativeto autologous connective tissue. Acellulardermal matrix has also been used alone or withvarious grafting materials to cover immediatelyplaced implant sites (28, 29, 64). Gingival graftshave been used as well to augment sites that have


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received immediately placed implants. Estheticoutcomes from this technique are good, but theprocedure requires a second surgery for graft procurement(40). The palatal advanced flap or pediculatedflap is another useful surgical technique formaxillary immediate implant cases (Fig. 3A F) (32,48, 54 59). The technique provides adequate tissuemobility and bulk, facilitating a complete, precise,and highly predictable coverage of the extractionsite in large defect areas, and in cases of multipleimplants. The main disadvantage of this techniqueis the prolonged and uncomfortable secondarypalatal tissue healing.ConclusionsThis paper has reviewed the history, predictability,rationale, treatment planning steps, and treatmentfor implant placement immediately after toothextraction. Multicenter studies have validated thepredictability of placing implants at the time ofextraction provided these procedures are appropriatelyplanned. To date, evidence for placement ofbone substitutes adjacent to small bone defects relatedto immediately placed implants indicates thatthis technique appear safe, although these materials

do not appear predictably to promote osseointegration.There is insufficient evidence that socket preservation procedures predictably maintain socketanatomy without crestal resorption. Bone substitutesimplanted into extraction sockets may interfere withnormal bone healing and ultimately osseointegration.A minimally invasive surgical technique in theplacement of immediate implants offers severaladvantages and should be employed whereverpossible.

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Tugas Kuliah Implant .txt