Abstract Session VI: Reconstruction & Pathology

References

Ehrenwerth, J., Donielson, D.: Pulse oximetry in the post-anesthesia care unit. J Post Anesth Nurse 2:9- 11, 1987

Rice, V.: Clinical hypoxia. Crit Care Nurse 1:21-31, 1980

Funding provided by UCSF Dept. of OMS Research Fund

Four Year Results with Posterior Maxillary Integral Implants Michael S. Block, DMD, LSU School of Dentistry, Dept. of OMS, 1100 Florida Ave., New Orleans, LA 70119 (Silvia, C.P., Kent, J.N.)

Since July 1984, 159 hydroxylapatite coated dental implants (Integral, Calcitek, Inc., Carlsbad, CA) have been placed into the posterior maxilla for partial or total reconstruction of edentulous arches in 48 patients. 79 implants were placed into the right posterior maxilla and 80 implants were placed into the left posterior maxilla. Eleven 8mm, 78 lOmm, 47 13mm and 23 15mm long implants were used. If less than 6mm alveolar bone was present, simultaneous sinus bone grafts were used. 54 implants have been placed into 18 autogenous bone grafted sinuses in 11 patients and 5 implants have been placed into demineralized bone grafted sinuses in three patients.

After three months for healing (or six months for grafted sinuses), the implants were exposed for placement of the abutments for restoration. 50% of the implants required thinning of the gingiva to result in three mm tissue thickness for adequate hygiene. Overdenture resto- ration included 4 bar-clips, 1 bar-clip with magnet, and 1

ball-attachment. Fixed restorations included 9 full-arch prostheses (acrylic occlusal), 35 fixed partial dentures (porcelain fused to metal occlusal), and 12 long span prostheses (porcelain fused to metal) involving implants as pier abutments.

Of the 159 implants restored for at least six months (range 6 months to 4 years), 4 implants in one patient were removed due to malposition, 1 was slept due to malposition in a grafted sinus, 2 implants were removed due to lack of bone support (2mm of implant in bone, with 6mm of implant length into ungrafted sinus), and 2 were removed due to excessive bone loss at implant exposure, for a total of 9/159 (5.7%). At longest time F/U, 8% had greater than 2mm vertical bone loss (facial predominant) most likely as a result of excessive occlusal forces, thin bone or dehiscence of the implant at placement, implant exposure during the healing period, bone ischemia associ- ated with large flaps and sinus elevation, or poor oral hygiene. These “morbid” implants were salvaged with flap surgery combined with hydroxylapatite grafts. The gap surgery resulted in 50% reduction in pocket depth and soft tissue that could be maintained by the patient,

Important factors for posterior maxillary implant suc- cess was a balanced restoration preventing excessive occlusal forces, maintenance of excellent oral hygiene and avoiding trauma to the ridge during the healing period.

References

Kent, J.N., Block, MS. et al.: Biointegrated hydroxylapatite coated dental implants-five year results and observations. submitted to JADA, 1989

Kent, J.N. and Block, MS.: Simultaneous maxillary sinus floor grafting and placement of hydroxylapatite coated implants. J Oral Maxillofac Surg 47(3):238-242, 1989

No funding provided

Alveolar Ridge Augmentation with Porous and Nonporous Hydroxylapatite Mohamed El Deeb, DDS, MS, Univ. of Minnesota School of Dentistry, Div. of OMS. 5 15 Delaware St. SE, Minneapolis, MN 55455 (Steele, C.E., Morstad, A.T.)

Preclinical and clinical studies have separately shown the compatibility and effectiveness of nonporous (NPHA) and porous (PHA) hydroxylapatite for augmenting atro- phic alveolar ridges. The purpose of this study is to evaluate the particulate NPHA and PHA as alveolar ridge augmentation materials in humans.

Methods: Forty-two patients (35 female and 7 male) ranging in age from 38 to 74 years had augmentation to 44 ridges. Twenty-three ridges were augmented with NPHA and 21 ridges with PHA. The patients were evaluated clinically by one oral and maxillofacial surgeon and one prosthodontist at 1,3,6,12,18 and 24 months postoperatively. A patient questionnaire regarding den- ture satisfaction was also completed at each follow-up interval.

Results: The NPHA and PHA materials consolidated within a range of seven to 12 weeks. The postoperative complications included inflammation (16 NPHA and 4PHA cases), nerve paresthesia (7 NPHA and 10 PHA cases), implant displacement (15 NPHA and 4 PHA cases), dehiscence (4 NPHA and 5 PHA cases) and suture abcess (3 NPHA and 2 PHA cases). Radiographic evaluation revealed both materials maintained ridge height with exception to minor settling. Histologic examination of specimens revealed bone growth limited to the PHA augmented ridges. Prosthodontic evaluation demon- strated the denture stability improved by 100% for NPHA and PHA ridges while denture retention improved by 95% for the NPHA ridge and 100% for the PHA ridges. Patient satisfaction was 77% improved for NPHA cases and 67% improved for the PHA cases.

Conclusion: The two-year clinical results indicated that NPHA and PHA are satisfactory alveolar ridge augmen-

AAOMS . 1989 113

Abstract Session VI: Reconstruction & Pathology

tation materials. The PHA material, due to the superior tissue and bone infiltration, presented fewer complica- tions associated with implant displacement and provided a more reliable ridge for denture construction and func- tion.

References

Tumor differentiation: All tumors of (2 14) were graded pathologically, with (71%) classified as well differenti- ated, (26%) moderately differentiated and (3%) poorly differentiated. The five year survival rates were 63%, 54% and 40% respectively with no significant differences among the groups.

Tumor thickness: The estimated tumor thickness was recorded in 96 cases at first admission, with 31 less than

Rothstein, S.S., Paris, D.A. and Zacek, M.P.: Use of hydroxylapatite for the augmentation of deficient alveolar ridges. J Oral Maxillofac Surg 41:224,1984

Piecuch, J.F.: Augmentation of atrophic edentulous ridge with porous hydroxylapatite. Dent Clin North Am 30:291, 1986

Departmental funding provided

Prognostic Factors in Buccal Mucosal Squamous Cell Carcinoma= A Retrospective Analysis Baizheng Song, DDS, Shriners Burns Institute, Room 244 (Oral Surgery Lab), 50 Blossom St., Boston, MA 02114 (Qiu W-L, Liu, S.)

6mm and 65 equal to or greater than 6mm. The five year survival rates were 75% and 54%, respectively (P < .05).

Regional lymph nodes: All of the patients had surgery. One hundred ninety three patients underwent some form of neck dissection. Positive nodes were pathologically confirmed in 77 cases, for an incidence of regional lymph node metastasis of 40%. The five year survival rate of those with positive nodes was 43% and of those with negative nodes 68% (P < .05).

Immediate reconstruction: Immediate reconstruction was carried out in 122 patients (57%). The five year survival rate of those whose defects were reconstructed immediately was 65% and those whose defects were not was 59% (P > .05).

Conclusions: 1) Our study demonstrated that the follow- ing were poor prognostic indicators for buccal squamous cell carcinoma: A. T4 Tumor; B. Positive regional lymph

In Southern China, buccal mucosa is the second and third most common site for oral squamous cell carcinoma. In our retrospective study, life table and Mental- Haeszel’s analysis were used to analyze the survival of

nodes; C. Tumor thickness greater than 6mm; D. Involve- ment of contiguous structures. 2) Immediate reconstruc- tion did not affect the five year survival rate nor did the differentiation of the tumor.

214 patient with squamous cell carcinoma of the buccal mucosa who presented to the Shanghai Ninth People’s Hospital, Shanghai, China from 1960 to 1986.

References

Of the 214 patients initially evaluated 20 were lost to follow up and-the remainder- (194) were followed from 1-21 years. The survival rates at 3,5 and 10 years were 67%, 62% and 52% respectively.

Sex and age: One hundred thirty three patients were

Qiu, W-L et al.: (1987) Tumors and Tumor-like Diseases in the Oral and Maxillofacial Region. In: Handbook of Oral and Maxillofacial Surgery, cd by Wei-liu Qiu 1st ed. People’s Health Pub., Beijing p. 261

Urist, M.M. et al.: (1987) Squamous Cell Carcinoma of the Buccal Mucosa: Analysis of Prognostic Factors. Am J Surg 154:411

male and 81 female. The age ranged from 18-72, with the largest group (34%) between 50-59.

Funding provided by Shanghai Second Medical University

Location: One hundred forty four patients with pri- mary lesions were arbitrarily divided into four groups: 1) Anterior (the primary lesion located anterior to the first molar) 10%; 2) Posterior 39%; 3) Combined anterior and posterior 34%; and 4) Involvement of the contiguous structure 17%. The 5 year survival rate was 68%, 65%, 68% and 37% respectively. The 4th group was signifi- cantly different from the 3 others (Pc.01).

Fine Needle Aspiration Cytology: An Analysis of 89 Head and Neck Cases Jay C. Platt, DDS, Dept. of OMS, 1121 W. Michigan St., Indianapolis, IN 46202 (Davidson, D.D., Nelson, C.L.)

Tumor classification: Using the staging of the Shanghai Fine needle aspiration cytology has been used in the Head and Neck Tumor Society (similar to the staging of head and neck region to diagnose a variety of benign and the Union Internationale Cancer Committee) for the 177 malignant conditions. In many cases this technique has patients who presented prior to any treatment, 11 were proven to be a reliable and appropriate alternative to open classified as T 1, 11 as T2,90 as T3 and 65 as T4. The five surgical biopsy. In a recent two year period 89 fine needle year survival rate was lOO%, 67%, 65% and 53%, respec- aspiration biopsies (FNAB) were performed on head and tively. There was no significance between T2 and T3, neck lesions in 8 1 patients at Indiana University Medical otherwise all comparisons between the groups were signif- Center. The age range of the patients was from 6 to 97 icantly different (Pc.05). years. There were 54 males and 27 females.

114 AAOMS l 1989