Poor oral function and inferior self-esteem are just a couple of the many difficulties associated with tooth loss

1. Dental Implant Complications:
Too Much Sinus and Too Little
Bone

2. Poor oral function and inferior self-esteem are just a couple of the
many difficulties associated with tooth loss. Complete or partial
dentures, often the solution to the problem of tooth loss, may not
restore oral function completely because of poor fit due to jaw bone
deterioration. Visit Infuse bone graft complications for more info.
Bridges, often the solution to single tooth loss, have their drawbacks
too, because placing a bridge requires the teeth surrounding the
missing tooth to be ground down and compromised.

3. To improve the aesthetics and function of tooth
replacement, dental implants were developed and have
gained popularity in recent years. Dental implants are
titanium "screws" which are placed in the jawbone
replacing the root of the lost tooth. Dental implants provide
an alternative to standard removable complete and partial
dentures and bridges while improving chewing function
almost completely.

4. The Problem
In order to be a candidate for the dental implant placement
procedure, a patient must have sufficient bone height and
width to support the titanium post or artificial tooth root.
Unfortunately, if a patient has been without a tooth or teeth
for a prolonged period of time, the bone that once
supported the teeth becomes weakened and deteriorates,
resulting in a lack of bone height to sustain a dental
implant. This is especially true when tooth loss occurs in
the maxillary (upper) jaw bone. Because the maxilla rests
against the sinus, when bone loss occurs, the sinus
expands to fill the space once occupied by jaw bone.

5. The Solution
To solve this issue, sinus augmentation (lift) procedures
have been developed allowing bone in the upper jaw to be
regenerated providing ample space to place a dental
implant. The sinus lift procedure, invented in the mid 1970's
has been refined and is now frequently successfully
performed. Different versions of the sinus lift procedure
have evolved over time, each successful in different cases.

6. Successful, predictable dental implant placement in the
posterior maxilla typically requires a minimum of 10mm of
vertical bone height. Moreover, bone density in the
posterior maxilla is often poor, which could lead to
complications during implant fixation. To address these
problems, maxillary sinus elevation surgery was developed
to increase the amount of bone available for implant
placement and has proven successful and become popular,
allowing patients with insufficient bone to undergo dental
implant surgery. The type of sinus augmentation that a
surgeon chooses to use on a given patient depends on the
surgeon's preference as well as patient anatomy.

7. Types of Sinus Augmentation (Lift) Procedures
The Lateral Window Technique (LWT)
Implant placement can be performed simultaneously with
the sinus elevation procedure or following a healing period
that can last 6-9 months. Immediate placement during sinus
elevation reduces overall healing time and eliminates
another surgical procedure, which can be desirable to
patients. The decision to place an implant during sinus
augmentation is dependent on the presence of adequate
bone volume and quality to provide for initial stability of the
implant. Rosen and colleagues (1999) recommended at
least 5mm of native bone for immediate implant placement
during sinus augmentation.

8. Lateral Window Sinus Augmentation: The lateral approach
involves a modified Caldwell-Luc operation to gain access
to the sinus cavity. A bony window is created in the lateral
maxillary wall, the Schneiderian membrane is elevated, and
bone grafting material is a combination of autogenous bone
and allograft. An absorbable collagen membrane is placed
between the bone graft and the membrane as well as over
the bony window.

9. This technique is usually the preferred method of sinus
elevation in situations of poor bone quality and minimal
residual bone height because it allows for direct
visualization and accurate bone placement and volume at
the position of the implant. Also, tearing of the membrane
can be easily treated, minimizing contamination of the graft
during healing.
http://www.consumerinjuries.com/infuse-bone-grafts/

10. This technique is usually the preferred method of sinus
elevation in situations of poor bone quality and minimal
residual bone height because it allows for direct
visualization and accurate bone placement and volume at
the position of the implant. Also, tearing of the membrane
can be easily treated, minimizing contamination of the graft
during healing.
http://www.consumerinjuries.com/infuse-bone-grafts/