Improved Technique for Localized Ridge Augmentation*

A Report of 21 Cases
Edward P. Allen,f Craig S. Gainza, Gregory G. Farthing and
Dewey A. Newbold
Accepted for publication 15 October 1984

Topographical aberrations in a residual edentulous ridge often prevent establishment

of a satisfactory pontic/ridge relationship. An improved technique is described for predictable
augmentation of localized alveolar-ridge deficiencies. Results are reported from 21 cases
involving 26 sites. All 14 sites using fibrous connective tissue grafts demonstrated shrinkage,
although an improvement in residual ridge contour was obtained. Hydroxylapatite implant
material was placed in 12 sites with shrinkage seen in only two sites. Advantages, require-
ments for success and technical considerations of the improved technique are discussed.

Proper pontic-residual ridge relationship is a critical Type C—Combined loss of ridge contour in both
factor in fixed prosthodontics. properly constructed
A apico-coronal and buccolingual dimen-
pontic must satisfy demanding requirements of func- sions.
tion, esthetics and cleansability. Topographical aberra- The ridge deformity may be further described by
tions in the residual edentulous ridge often prevent the assessing the depth of the defect relative to the adjacent
establishment of an ideal pontic-to-ridge relationship, ridge:
and in such cases residual ridge surgery may be indi- Mild—less than 3 mm.
cated. ' A ridge that is excessive in its dimensions may Moderate—3 to 6 mm.
be reduced by appropriate hard and soft tissue resective Severe—greater than 6 mm.
procedures. A much more difficult situation exists when Recently, there have been reports describing surgical
the remaining alveolar ridge is markedly deficient. Until procedures for reconstruction of deformed, partially
recent years, little could be done surgically to alter the edentulous ridges. Abrams3 described a de-epithelial-
deficient ridge, and restorative dentists were forced to ized connective tissue pedicle or roll technique. The
compromise pontic design in ways that in many cases roll technique is most useful in restoring defects in the
were only marginally acceptable from a functional and/ apico-coronal dimension but requires sufficient soft
or esthetic standpoint. The resulting restoration was tissue thickness directly over and palatal to the residual
often a disappointment to both the patient and therapist ridge crest. A technique using fibrous connective tissue
despite the most conscientious efforts. grafts was originally reported by Langer and Calagna4'5
Causes of alveolar ridge deformities include devel- and later by Garber and Rosenberg,6 and has been used
opmental defects, advanced periodontal disease, trau- successfully to restore moderate defects in the bucco-
matic injury and surgical trauma. The eccentrically lingual dimension. Seibert2-7 8 described a full thickness
placed maxillary incisors with their extremely thin fa- onlay grafting technique for augmenting moderate to
cial and thick palatal plates are common sites for ridge severe ridge defects. In one case, he described the im-
deficiencies. The thin facial plate predisposes to fracture plementation of hydroxylapatite (Durapatite®) when
upon extraction or trauma. Subsequent healing often onlay grafting failed to correct satisfactorily a severe
results in ridge deficiency, scar formation and compro- defect. Cohen9 recently described augmentation of a
mised prosthetics. single site using hydroxylapatite (Calcitite®). However,
In a modification of Seibert's original classification,2 placement of the initial incision directly over the defect
different types of ridge deformities may be described as site resulted in an open wound exposing the implant
follows: particles, consequently delaying healing and jeopardiz-
Type A—Apico-coronal loss of ridge contour. ing the final result.
Type —Buccolingual loss of ridge contour. Durapatite is a nonresorbable polycrystalline form of
*
Baylor College of Dentistry, Dallas, TX 75246. hydroxylapatite that is well tolerated by hard and soft
t Associate Professor Clinical, Department of Periodontics. tissues and produces neither an immune nor inflam-
195
 J. Periodontol.
196 Allen, Gainza, Farthing, Newbold April, 1985

matory response. 11 It has also been used successfully from either the internal surface of a palatal flap or from
for augmentation of completely edentulous maxillary a tuberosity. The deficient site was overfilled in an
and mandibular ridges.12 attempt to compensate for postoperative shrinkage.
The purpose of this paper is to describe an improved The technique used for the hydroxylapatite augmen-
technique for localized ridge augmentation and to pres- tations was as follows (Fig. 1 ):
ent results from 21 cases. Advantages of this technique 1. Parallel incisions were made close to the teeth
over those previously described and requirements for adjacent to the deficient ridge, beginning approximately
success will be outlined. Results using ceramic material 6 to 12 mm palatal to the ridge crest. These incisions
will be compared with soft tissue augmentation proce- were extended over the ridge crest and facially toward
dures. the mucogingival junction. Care was taken to avoid the
sulci.
MATERIALS AND METHODS
Table 1
Twenty-one patients having ridge deficiencies in 26
sites are included in this report. All defects were in the Distribution of Severity and Defect Type
maxillary arch with 19 involving the incisor area and Variable Type A Type Type C
seven involving the cuspid and bicuspid area. Eighteen Mild 2
sites were single tooth spaces and eight were two-tooth Moderate 12
Severe 0
spaces. The distribution of severity and defect type is
shown in Table 1.
In 14 sites, fibrous connective tissue grafts were used Table 2
and in 12 sites, hydroxylapatite implants were used to Distribution of Severity and Type of Implant Used
correct the defects. The distribution of severity and Fibrous connective
Variable Hydroxylapatite tissue
implant/graft type used is demonstrated in Table 2.
The recipient sites which were to receive fibrous Mild
connective tissue grafts were prepared according to Moderate
Garber and Rosenberg.6 Donor material was obtained Severe

Figure 1. A, Incision outlining palatal pedicle with extension facially to provide increased mobility of the flap. B, Reflection of split-thickness
palatal pedicle flap exposing full-thickness pouch.C, Implant particles shown within defect area. Note sutures placed facially to aid retention of
particles. D, Additional sutures placed to secure pedicleflap to all margins. (Courtesy Dr. J. Y. Cho).
Volume 56
Number 4 Technique for Ridge Augmentation 197

2. A third incision connected the parallel incisions 9. Periodontal dressing was placed over the surgical
palatally, thus outlining a palatal pedicle which was site for 1 week.
raised by sharp dissection as a split-thickness flap to the Patients were seen for postoperative care and obser-
ridge crest. vation at 1 week, 3 weeks, 6 weeks, 3 months and 6
3. From the ridge crest, a full-thickness flap was months. Shrinkage and stability of the augmented area
elevated and a pouch formed in the defect area by blunt were determined subjectively at each visit.
dissection. Care was taken to limit the boundaries of
the pouch within the deficient area.
RESULTS AND DISCUSSION
4. Where necessary, the parallel incisions were ex-
tended to allow access for elevation of the facial tissue All 26 sites demonstrated improved residual ridge
and to free the flap for facial or coronal movement in contour allowing better esthetics in the final restoration.
the defect area. Of the 14 sites using fibrous connective tissue grafts, all
5. Once the facial tissue had been elevated, the par- exhibited postoperative shrinkage despite deliberate
allel incisions were sutured facially to the alveolar ridge overfill at the time of surgery. Such shrinkage occurred
crest in preparation for hydroxylapatite placement. without regard to severity of defect, being observed in
6. Alveolograft® was placed into seven defects using all three mild defects treated. One grafted site required
the manufacturers syringe, and in five sites, Periograf® a second-stage procedure to achieve satisfactory results.
placement was accomplished with a sterile plastic amal- Shrinkage occurred within the first 4 to 6 weeks post-
gam carrier. operatively. The augmented sites have remained stable
7. The pedicle flap was secured at all margins with after the initial shrinkage for up to 3 years.
multiple interrupted 5-0 chromic gut sutures. Due to No shrinkage was observed in 10 of the 12 sites using
facial and/or coronal movement of the flap, a small hydroxylapatite implant material (Fig. 2). One site ex-
area was left to granulate in on the palatal aspect. hibited a perforation due to inadequate thickness of the
8. Temporary appliances replacing the missing teeth facial mucosa, and a small amount of the implant
were relieved approximately 3 mm to prevent pressure material was lost. In another instance, a portion of the
on the flap from edema during the initial stages of flap sloughed as a result of pressure from a temporary
healing. removable prosthesis. Postoperative swelling was noted

Figure 2. A, Incisai view of Type defect with probe demonstrating moderate depth. B, Restoration ofridge contour with hydroxylapatite implant.
C, Four weeks postoperatively shows reduction of swelling and lack ofshrinkage.
Figure 3. A, Maxillary left central and lateral incisors exhibiting hopeless prognosis and poor cosmetic appearance prior to removal. B, Four
weeks postextraction, a severe Type C defect is apparent. C, Facial view of defect immediately prior to augmentation procedure. 6 weeks
postextractions. D, Initial incisions outlining palatal pedicle. Note that the incisions avoid the sulci while allowing elevation of the flap over the

for 1 to 2 weeks, after which stability of the augmented 3. The position of the mucogingival junction can be
sites was observed for up to 18 months. maintained or restored.
Overall, the most rewarding results were obtained
using hydroxylapatite implant placed via the palatal REQUIREMENTS FOR SUCCESS
pedicle flap approach (Fig. 3). Choice of particle size
and delivery system appear to be a matter of operator If the technique described is followed carefully, con-
preference. Comparable results were obtained using the sistent and predictable results can be obtained. The
Periograf (40-60 mesh) and Alveolograf ( 18-40 mesh) following considerations are important to ensure suc-
brands of hydroxylapatite. cess with the technique:
It is the authors' opinion that the technique outlined 1. Crevicular depth on the teeth adjacent to the
has definite advantages over the fibrous connective edentulous ridge should be shallow. If pockets are pres-
tissue grafting technique and other implant techniques ent, these should be treated prior to augmentation
previously reported in the literature. procedures.
The advantages of the hydroxylapatite implant ma- 2. There must be an adequate zone of keratinized
terial over fibrous connective tissue grafts are: gingiva around teeth adjacent to the edentulous ridge
1. Only one surgical site is required. so as to withstand surgical and restorative procedures.
2. An unlimited amount of implant material is avail- This can be provided by soft tissue grafting procedures
able. if necessary.
3. Achievement of proper contour is more predict- 3. There must be an adequate quantity and quality
able. of soft tissue in the edentulous area to allow the desired
The palatal pedicle flap approach offers the following degree of elevation and sufficient flap thickness to
advantages over other flap designs previously reported: prevent perforation. Soft tissue deficiencies should be
1. Total soft tissue closure may be achieved over the corrected by grafting prior to the placement of implant
synthetic implant particles. material.
2. The flap can be elevated sufficiently to achieve 4. Vertical incisions should be kept out of the sulci
proper residual ridge contour facially and/or coronally. of adjacent teeth. This allows complete soft tissue clo-
Volume 56
Number 4 Technique for Ridge Augmentation 199

entire defect area. E, Split-thickness flap elevated and implant material placed within defect. F, Immediate postoperative appearance. G,
Appearance ofridge 4 weeks postaugmentation. Note lack ofshrinkage. H, One year postaugmentation with finalfixed restoration in place. Note
complete correction ofridge deformity.

sure preventing extrusion of implant particles through ridges, using full thickness onlay grafts. Part I. Technique and wound
the sulci. healing. Compend Cont Ed Gen Dent 4: 437, 1983.
3. Abrams, L.: Augmentation of the deformed residual edentu-
5. Dissection of the mucoperiosteal pouch should be lous ridge for fixed prosthesis. Compend Cont Ed Gen Dent 1: 205,
carefully confined to the defect site and the implant 1980.
material placed without excessive pressure to prevent 4. Langar, B., and Calagna, L.: Sub-epithelial graft to correct
displacement of the implant and loss of desired contour. ridge concavities. J Prosthet Dent 44: 363, 1980.
5. Langar B., and Calagna, L.: The Sub-epithelial tissue graft, a
6. Temporary appliances should be relieved suffi-
new approach to the enhancement of anterior cosmetics. Ini J Per-
ciently to prevent any impingement on the flap during iodontics Restorative Dent 2: 23, 1982.
healing. If possible, removable appliances should not 6. Garber, D. ., and Rosenberg, E. S.: The edentulous ridge in
be worn during the 1 st week of healing. fixed prosthodontics. Compend Cont Ed Gen Dent 2: 212, 1981.
7. A minimum of 6-weeks healing should be allowed 7. Seibert, J. S.: Soft tissue grafts in periodontics. P. J. Robinson
and L. H. Guernsey (eds), Clinical Transplantation in Dental Spe-
prior to performing restorative procedures. This permits cialties, pp 107-145. St. Louis, The C. V. Mosby Co, 1980.
sufficient time for tissue maturation prior to crown 8. Seibert, J. S.: Reconstruction of deformed, partially edentulous
preparation and impression procedures. ridges, using full thickness onlay grafts. Part II. Prosthetic/periodontal
This improved technique offers a refined and pre- interrelationships. Compend Cont Ed Gen Dent 4: 549, 1983.
dictable means of enhancing the quality of restorative 9. Cohen, H. V.: Localized ridges augmentation with hydroxyl-
apatite: report of case. J Am Dent Assoc 108: 54, 1984.
dentistry in cases of localized loss of alveolar ridge 10. Jarcho, M., Bolen, C. H., Tjomas, M. B., et al.: Hydroxylapa-
contour. tite synthesis and characterization in dense polycrystalline form. J
ACKNOWLEDGMENT Mater Sci 11:2027, 1976.
The authors wish to express their appreciation to Dr. J. Y. Cho 11. Jarcho, M., Kay, J. F., Gumaer, K. L, et al.: Tissue, cellular
for preparation of the artwork and to Lauri Hurley for her assistance and sub-cellular events at a bone-ceramic hydroxylapatite interface.
in preparing the manuscript. J Bioeng 1: 79, 1977.
12. Laskin, D. M.: Observations and reflections on durapatite.
REFERENCES Compend Cont Ed Gen Dent (suppl) 2: 577, 1982.
1. Stein, R. S.: Pontic residual ridge relationship: a research
report. J Prosth Dent 16: 251, 1966. Send reprint requests to: Dr. Edward P. Allen, Baylor College of
2. Seibert, J. S.: Reconstruction of deformed, partially edentulous Dentistry, 3302 Gaston Ave, Dallas, TX 75246.