Uncovering Medical Assignment Help

Uncovering

The length of time necessary to achieve integration varies from site to site and may require modification based on the particular situation. Successful loading with shorter integration times has been reported when various protocols
are followed  (see Table 14-2 for conventionally accepted times for integration based on historical experience, which should serve as a referece point). Although shorter times may be possible, longer times may be required if the bone quality at surgery was poor or if there  was a question regarding ‘the adequacy of bone-to- -implant interface at the time of placement. In a single-stage system, the implant remains exposed after surgery artd throughout the healing phase. After appropriate integration time, restoration can proceed. In a two-stage system, the implant must be uncovered

FIG. 14-52 Tissue punch removes small plug of tissue overlying implant and allows access for attachment of superstructure.,

FIG. 14-52 Tissue punch removes small plug of tissue overlying implant and allows access for attachment
of superstructure.,

BOX 14-6

Indications for Various Uncovering Techniques

TIssue Pundt
Requirements: .
Adequate attached tissue
Implant can be palpated
Advantages:
least traumatic
Periosteum not reflected-less bone resorption
Earl}timpressions’ are possible
Disadvantages:
Sacrifice attached tissue
Unable to visualize bone
.Unable to visualize implant and superstructure interface
Crestal Incision
Requirements:
Adequate attached tissue
Advantages:. . .
Does not require implants to be palpable
Easy access
Minimal trauma
Able to visualize bone
Able to visualize implant and superstructure interface
Disadvantages:
Periosteum reflected-may lead to bone loss
Apically Repositioned Flap
Advantages:
Improve vestibular depth, attached tissue
Disadvantages:
Longer healing time
Bone loss as a result of reflection of periosteum
Technically more difficult

before restoration. The goals of surgical uncovering are to  accurately attach the abutment to the implant, preserve attached tissue, and recontour and thin tissue or add form and thickness to existing tissue. This may be accomplished by one of the following general techniques: the tissue punch, crestal incision, flap repositioning, or soft tissue grafting. Each has its own advantages . and indications (Box 14-6).  he simplest method of implant uncovering is the tissue punch (Fig. 14-52). This method of  reccovering is easy to perform, only minimally disturbs the tissue surrounding the implant, and produces minimal patient discomfort.
To. use this t echnique, the implant must be locatedwith certainty below the tissue. Use of the punch is contraindicated if inadequate attached tissue will remain after the punch is used. The punch also has the slight disadvantage
of not allowing visualization of the bone. If a graft was placed or if there was some question regarding the relationship between the marginal bone and .the implant, this technique would not allow assessment at the time of uncovering nor could nonresorbable guided tissue regeneration  embranes be removed. This technique also makes visualization of the abutment-toimplant body interface difficult. The operator must rely on’ tactile sense to determine if the abutment is completely seated on the implant body.
If the implants cannot be palpated or the cl inician needs to visualize the marginal bone, a crestal incision over the implant is indicated. If sufficient attached tissue is found, a punch or scissors can be used to contour the
edge of the flap to conform to the implant before wound closure. This technique will also heal rapidly because primary closure exists. This technique also requires adequate attached tissue. . ff attached tissue surrounding the implant is limited or inadequate, an apically repositioned flap is the uncovering method of choice. A crestal incision developed in a
supraperiostcal plane is performed to develop a splitthickness flap. The flap is then sutured over the facial surface at a more apical level. Healing occurs by secondary intention. This technique requires the longest healing

FIG. 14-53 A, Pedicled connective tissue graft from the palate can be used to augment the labial soft tissue contour. 8, Free connective tissue graft can also be used to accomplish the same thing ..

FIG. 14-53 A, Pedicled connective tissue graft from the palate can be used to augment the
labial soft tissue contour. 8, Free connective tissue graft can also be used to accomplish the
same thing ..

time and is more jinful. It preserves and increases the  amount of .lttache~oft tissue, but does not improve tis-  .sue thickness. In some situation She bulk of soft tissue is not adequate  to produce proper Ctltour around the implant. This is especially a problem nthe anterior maxilla where, despite adequate osseous conhr and proper implant placement, a localized depression, the facial margin of the crown is found that will compr<nise esthetics. In this situation a pedicled or free connecva tissue graft is an effective way to restore soft tissue fOfIiaround the imp ant (Fig. 14-53). These procedures allow nnor changes in the tissue height around the implant crovi but cannot substitute for adequate osseous form thatnust always be maintained (or  reestablished first). In situations in whic the overlying tissue is very thick, it may be necessar; to recontour tissue. A carbon dioxide laser or electro  a~ry is quite effective. Laser or bipolar cautery poses less 15kof damage to jhe implant or bone than  onventional’lonopolar cautery.After the implant is exposed the implant abutment is placed. Two approaches can be used to do this: One approach. is to place the abutment that the restorative  dentist will use in the restoration. This is effective in the’ mandible and posterior maxilla where esthetics is ‘of less  concern. The other technique is to place a temporary healing abutment that will remain until the tissue heals and will then be discarded and replaced by an abutment. This may be a factory or custom-made abutment. A custom abutment will help contour soft tissue for better esthetic results. A custom abutment is made from an index of implant position recorded at the time of placement. When the abutment is placed, it is important that it be completely seated on the implant body without gaps or intervening soft or hard tissue. In systems that have antirotational facets built into the implant, these must be aligned to allow complete seating of the abutment. The abutment-to-implant jnterface should be evaluated radi
ographically immediately after uncovering. If a gap i present, the abutment must be repositioned (Fig..14-54)

FIG. 14-54 Radiographs should be taken after attachment of abutments and before impressions. This radiograph shows that abutments are not properly seated on implant body, which could lead to error In fabrication of' implant prosthesis if not properly seated _ before impression.

FIG. 14-54 Radiographs should be taken after attachment of abutments
and before impressions. This radiograph shows that abutments
are not properly seated on implant body, which could lead to
error In fabrication of’ implant prosthesis if not properly seated
_ before impression.

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