A longitudinal study comparing scaling, osseous surgery, and modified Widman procedures: results after 5 years

BACKGROUND

Scaling and root planing, osseous surgery, and modified Widman procedures are effective methods for treating periodontal diseases. Studies have been carried out to determine if these procedures are more effective than others in reducing clinical probing depths, while maintaining clinical attachment levels. The purpose of this report is to present 5-year results from a longitudinal study comparing scaling and root planing (SRP), osseous surgery (OS), and modified Widman (MW) therapies. The study has been completed for 12 years.

METHODS

Sixteen adult patients with moderate to advanced periodontal disease were treated with initial scaling and oral hygiene procedures in a private practice. Posthygiene data were used to compare changes in plaque and gingival indices, probing depth (PD), clinical attachment levels (CAL), and recession. Frequency distributions were used to compare changes at individual sites. The first published report was from baseline to one year. This follow-up report is from baseline through 5 years.

RESULTS

At 5 years, there were significant decreases in gingival and plaque scores. For the 3 procedures, there were significant decreases in baseline 4 to 6 mm PD (P<0.0001); however, there were no differences between the methods. Similar findings were noted for PD initially greater than 7 mm. At 5 years, OS had the greatest number of 1 to 3 mm sites (332 sites, 73.2%), while MW had the fewest number of 4 to 6 mm PD (98 sites, 21.8%). SRP had the fewest 7 mm and greater sites (15 sites, 3.4%). At 5 years, CAL loss for 1 to 3 mm PD was statistically significant for the 3 procedures. There were slight gains in CAL for 4 to 6 mm probing depths. These gains were not significant. Similar findings were seen for CAL for probing depths greater than 7 mm. OS had the greatest number of sites losing more than 2 mm of CAL (64 sites), followed by SRP (21 sites) and MW (34 sites), respectively.

CONCLUSIONS

This 5-year clinical trial demonstrates that with good patient maintenance excellent clinical results can be achieved with various methods of treatment. Within the limits of this study, SRP, OS, and MW were effective at reducing probing depths with slight changes in clinical attachment levels.

Multiple isoforms of the high molecular weight microtubule associated protein XMAP215 are expressed during development in Xenopus

We have cloned and sequenced cDNAs encoding two isoforms of XMAP215, a high molecular weight microtubule-associated protein identified in Xenopus eggs. XMAP215 is approximately 80% identical in amino acid sequence to the product of ch-TOG, a cDNA that is over expressed in certain human tumors [Charrasse et al., 1995: Eur J Biochem 234:406-413]. Northern and Western blots demonstrated that XMAP215 is expressed throughout development, from oogenesis to tadpole. We identified two XMAP215 transcripts differing only in the presence of a 108-bp sequence encoding a 36 amino acid insert. RT-PCR revealed that the transcripts encoding these two isoforms are expressed at distinct times during development: a transcript containing the insert (encoding XMAP215(M)) is expressed during oogenesis and is present through gastrulation. The second transcript (encoding XMAP215(Z)) lacks the 108-bp insert and is expressed from gastrulation onward. In situ hybridization demonstrated that XMAP215 transcripts are localized to the ectoderm of early embryos and in the developing nervous system during later development. These results suggest that XMAP215 plays important roles in at least two phases of development: (1) regulating the assembly of MTs during the rapid cell divisions after fertilization, and (2) regulating MT assembly during the development of the nervous system.

Retrospective case series analysis of the factors determining immediate implant placement

Implant placement at the time of extraction has become an acceptable treatment option. The formation of a restorative treatment plan frequently requires the removal of questionable and hopeless teeth. This retrospective case series analysis reports the reasons for tooth removal before immediate implant placement and provides a rationale for removing questionable and hopeless teeth. Root length is also analyzed as related to tooth loss. Between September 1986 and December 1998, 460 teeth were removed from 282 patients. Reasons for removal were advanced periodontal disease, endodontic complications, nonrestorable caries, roots fractures, short roots (< 14 mm in length), root resorption, and loosened posts. Implants were placed at the time of extraction. Tallies, frequency distributions, and percentages were used to determine individual and multiple reasons for extraction. For teeth with short roots, computerized measurements were made from periapical x-rays. Advanced periodontal disease and restored endodontically treated teeth with posts were the primary reasons for tooth extraction. Dental implants replaced 305 maxillary and 155 mandibular teeth.

A Prospective Multicenter Clinical Trial Comparing One- and Two-Stage Titanium Screw-Shaped Fixtures with One-Stage Plasma-Sprayed Solid-Screw Fixtures

BACKGROUND

Brånemark fixtures were originally placed in two stages, whereas titanium plasma-sprayed (TPS) solid-screws are placed in one stage. Long-term survival rates for both types of implants are excellent. Excellent survival rates have also been reported for machined screw-shaped (MS) titanium implants placed in one stage. A small number of studies have compared different implant systems and methods of implant placement.

PURPOSE

The purpose of this study is to report clinical outcomes from a prospective longitudinal, multicenter study comparing Brånemark MS fixtures (Nobel Biocare, Yorba Linda, California, USA) placed in either one or two stages with a one-stage TPS system (ITI Straumann, Waldenburg, Switzerland).

METHODS

A protocol was designed to compare implant survival rates, changes in crestal bone for titanium MS fixtures placed in one and two stages, and plasma-sprayed solid-screw fixtures placed in one surgical stage. Twenty-nine patients ranging in age from 24 to 82 years received MS fixtures in one stage. The average age for males was 58 years (n = 11), whereas the ages for females (n = 18) ranged from 15 to 84 years (average 58 years). Twenty-nine patients received machined titanium fixtures placed in two stages. There were 20 females ranging in age from 23 to 74 years (average 54 years) and 9 females ranging from 24 to 74 years (average 46 years). Twenty-five patients received TPS fixtures. There were 15 males, ranging in age from 57 to 79 (average 70), and 10 females, ranging in age from 40 to 83 years (average 62 years). Bone quality and quantity were determined from radiographs and during site preparation. Patient age, sex, location of implant placement according to jaw, length of fixtures, and number of lost fixtures were entered onto computer code sheets and continuously entered into a locked computer system. For one- and two-stage MS fixtures, nonstandardized periapical radiographs were taken at abutment connection and follow-up. Solid screws were x-rayed at prostheses connection and follow-up. The average time between implant restoration and radiographic follow-up was 15 months. The x-rays were scanned into a computer, and a program designed to measure radiographs was used to determine changes in crestal bone. Measurements for one- and two-stage MS fixtures were made from the top of the implant shoulder to the first bone to implant contact mesial and distally. Plasma-sprayed screws were measured from the bottom of the implant to the coronal most bone to implant contacts mesial and distally. Mesial-distal radiographic measurements were averaged and changes were compared using the t-test for related samples.

RESULTS

This report presents data from the 2- to 3-year follow-up examinations. Twenty-nine patients received 80 one-stage MS fixtures. Between 0 and 1 year, two fixtures were lost, resulting in a 97.5% cumulative survival rate (CSR). The CSR remained unchanged through the 2- to 3-year follow-up. Twenty-eight patients received 78 two-stage MS fixtures. One implant was lost prior to loading and two were lost between 0- and 1-year follow-up, yielding a 96.2% CSR at the end of 1 year. The CSR remained unchanged through the 2- to 3-year follow-up. Twenty-three patients received 78 solid-screw plasma-sprayed screws. One implant was lost prior to loading and one between the 0- to 1-year follow-up, accounting for a 97.4% CSR at the 2- to 3-year follow-up. Changes in bone crest measurements for one-stage titanium threaded fixtures were insignificant (-0.11 mm, p = .08, maxillary; 0.07 mm, p = .42, mandibular). For two-stage MS fixtures, crestal bone loss was insignificant in maxillae (-0.16 mm, p = .92) and significant in mandibles (-0.43 mm, p = .000). There was significant bone loss for TPS implants in maxillae and mandibles (maxillae, 1.31 mm, p = .04; mandibles, 0.98 mm, p = .000).

CONCLUSIONS

Cumulative survival rates for MS fixtures placed in one and two stages as well as one-stage TPS screws up to the 2- to 3-year follow-up examination were similar, indicating excellent clinical results. Radiographic measurements for changes in crestal bone loss were clinically insignificant for fixtures placed in one stage. For two-stage fixtures, maxillary changes were insignificant, whereas mandibular bone loss was statistically significant but clinically insignificant. Changes in crestal bone loss for TPS implants were statistically significant.

Osteoporosis and implant failure: an exploratory case-control study

BACKGROUND

Osteoporosis has been suggested as a risk factor for implant failure, but data supporting such a link are limited.

METHODS

A case-control study was designed to evaluate the association between osteoporosis and dental implant failure. Cases (n = 49) and controls (n = 49) were selected from a private practice. The following measures were collected for each patient: 1) peripheral dual-energy x-ray absorptiometry (pDEXA) bone measurements at the distal and proximal radius and ulna; 2) classification of bone quality and quantity at the time of implant placement; and 3) questionnaire data regarding potentially confounding variables. Generalized estimating equations were used to relate the likelihood of having at least one implant failure in an individual to osteoporosis measures.

RESULTS

The results suggested that there was no association between pDEXA scores at the radius and ulna and the risk for implant failure. For every 1-unit increase in bone density as measured by pDEXA t-score at proximal and distal radius and ulna, the risk for a patient to lose at least one implant changed by +14% and -6%, respectively (odds ratio, 1.14; 95% confidence interval, 0.80-1.62 and odds ratio, 0.94; 95% confidence interval, 0.71-1.23). The simple visual assessment of local bone quality had a moderately sized relationship to implant failure. Implants placed in sites with thin cortical bone increased the chance for a patient to lose at least one implant by 130% when compared to implants placed in a thick cortical layer or compact bone (odds ratio, 2.3; 95% confidence interval, 1.0-5.4).

CONCLUSIONS

This exploratory study suggests that a simple visual assessment of bone quality at the site of implant placement may be more informative regarding implant failure than pDEXA bone density measures obtained at peripheral bones. In order to determine whether peripheral osteoporosis measurements have a small or moderate association with implant loss, studies with larger sample sizes will be required.

Model Spinal Cord Injury System trends, and implications for the future

In the 25 years since the federally designated Model Spinal Cord Injury Systems program was started, many changes have occurred. The systems have increased in number and location and have changed in composition. Data are available on approximately 19,000 acutely injured traumatic spinal cord injured individuals, with more than 117,000 total records. This volume of data allows analysis of many trends affecting the care of people with spinal cord injuries. The time span covered by the database allows comparison of various time periods, including the most recent decade--during which managed care has emerged as a dominant force in health care evolution. This article summarizes these trends, based on information in the articles in this special issue devoted to the Model Spinal Cord Injury Systems. Finally, this article offers an analysis of future implications for SCI care in general and the federally designated Model Spinal Cord Injury Systems program in particular.

Formation of Bone around Titanium Implants Placed into Zero Wall Defects: Pilot Project Using Reinforced e-PTFE Membrane and Autogenous Bone Grafts

BACKGROUND

Guided bone regeneration (GBR) frequently is used to augment implants with various types of bone defects. The defects often are grafted with different materials, yet there is insufficient evidence that these materials enhance bone-to-implant contacts.

PURPOSE

The purpose of this pilot project was to test the principle of GBR to promote bone formation adjacent to commercially pure titanium implants placed within zero-wall defects. Histologic and histomorphometric measurements were used to evaluate new bone formation.

MATERIALS AND METHODS

Under appropriate anesthesia, deep, wide defects were created within the mandibles of two large dogs. Buccolingual bone was removed to the depth of the defects leaving only the mesial and distal walls. Of the eight implants placed, three were augmented with titanium-reinforced expanded polytetrafluoroethylene (e-PTFE) barriers and autogenous bone chips. Three sites were augmented with barrier membranes only, and two sites were not augmented or grafted and served as controls. Seven months after surgery the dogs were sacrificed and block sections were taken for histologic evaluation.

RESULTS

Histologic and histomorphometric measurements were used to evaluate new bone formation. Results from this evaluation revealed bone formation at the membrane-only sites and the membrane-plus-bone grafted sites. The bone grafts were completely incorporated by the newly formed marginal compact bone. For all treated sites, there was poor bone-to-implant contact. Histomorphometric measurements showed a trend toward greater bone formation at membrane-treated sites compared with control sites. However, autogenous bone grafting did not seem to affect the amount of newly regenerated bone.

CONCLUSIONS

Within the limits of this pilot project, findings show trends toward bone healing, indicating constant and enhanced bone regeneration over the exposed implant. Bone contact to the implant surface generally was poor.

Long-term evaluation of 282 implants in maxillary and mandibular molar positions: a prospective study

BACKGROUND

Placement of implants into molar positions presents diagnostic, surgical and prosthetic challenges. There are few reported studies for implants placed into molar positions. The purpose of this prospective longitudinal study is to report long-term clinical outcomes for 282 implants placed into molar positions.

METHODS

Two-hundred-twelve patients received 282 implants. Implant size, location, jaw shape, and bone quality were recorded for all implants placed into molar positions. Seventy implants were inserted in maxillae and 212 in mandibles. Marginal bone level changes in maxillae and mandibles were measured from non-standardized periapical radiographs taken at abutment connection and an average follow-up of 3.9 years. Mesial-distal implant measurements were made from the top of the implant cylinder to the first point of bone to implant contact. In mandibles, 39 implants were used for single molar replacements, 67 implants were placed into excellent bone quality (type I) and 113 were in good bone quality (type 11); 145 implants were placed into bone with moderate bone resorption (type B); 166 implants were placed in first molar positions and 46 in second molar sites.

RESULTS

At 6 years the cumulative success rate (CSR) for mandibular implants is 91.5%, and the success rate from the 2 to 3 year follow-up is 100%. Of the 70 implants placed in maxillae, 16 replaced single molars. Thirty-two implants were placed in jaw shape B with type 2-bone quality. For maxillary implants, the 6-year CSR was 82.9% and the success rate remained steady at 100% after the 2 to 3 year follow-up. For maxillary implants, at abutment connection the average marginal bone level was 1.67 mm, while at follow-up it was 1.98 mm. These differences were statistically significant (P = 0.04), but are not considered to be clinically significant. For mandibular implants, at abutment connection the mean marginal bone level as measured from radiographs was 2.11 mm, and at follow-up was 2.02 mm. This slight gain in bone level was not statistically significant and is not considered to be clinically significant.

CONCLUSIONS

Results of this prospective longitudinal study of implants placed into molar positions indicates favorable clinical outcomes. These CSR rates (91.5% mandibles, 82.9% maxillae) are less than what has been reported for implants placed into mandibular and maxillary anterior segments. Differences in outcomes between anterior and posterior locations may be related to bone quality and quantity.

Five-Year Evaluation of Implants Placed at Extraction and with Dehiscences and Fenestration Defects Augmented with ePTFE Membranes: Results from a Prospective Multicenter Study

BACKGROUND

Barrier membranes have been used to promote bone ingrowth on implants with dehiscences and fenestrations. Membranes also have been used to protect defects adjacent to implants placed at the time of extraction. The concept of guided bone regeneration relates to preferentially allowing cells from bone to migrate into various defects while excluding fibrous tissue and epithelium. The purpose of these procedures is to enhance bone-to-implant contact at the treated sites and to prevent mucosal complications.

PURPOSE

The purpose of this article is to report clinical outcomes for implants placed at the time of extraction and augmented with expanded polytetrafluoroethylene (ePTFE) and followed for 5 years. The outcomes for implants with dehiscences and fenestrations augmented with ePTFE barriers and followed up to 5 years also are reported.

METHODS AND MATERIALS

Four treatment centers participated in this study (Tucson, Gothenburg, Spokane, and Leuven). In the extraction group, teeth were removed for varying reasons, and Brånemark implants were placed and stabilized within the host bone. Defects present at the coronal implant aspect were covered with ePTFE barrier membranes. Flaps were rotated to cover the membrane-treated sites. If exposure of the material occurred prior to second-stage surgery, the membranes were removed. Barriers remaining unexposed were removed at second-stage surgery. The implants were followed up to 5 years. In the fenestration and dehiscence group, implants with exposed threads were augmented with ePTFE barrier membranes. The barriers were removed at appropriate intervals, and the patients were followed up to 5 years. Radiographic measurements were made from nonstandardized periapical radiographs at abutment connection and 1, 3, and 5-year follow-up visits.

RESULTS

Forty patients participated in the extraction group. They received a total of 49 implants. Three implants failed prior to loading. The 5-year cumulative survival rates for implants placed at the time of extraction were 93.9% and 93.8%, respectively, for maxillary and mandibular implants. The average maxillary mesial and distal marginal bone loss (1-5 yr) was 0.3 mm (standard deviation [SD] = 1.5) and 0.3 mm (SD = 1.0). In mandibles, the average mesial and distal bone loss (1-5 yr) was -0.2 mm (SD = 0.5) and -0.05 mm (SD = 0.6), respectively. The dehiscence and fenestration group included 44 patients. Twenty-six were followed for up to 5 years. Eight patients experienced total implant failure. For dehiscences and fenestrations, the cumulative survival rates were 76.8% and 83.8% for maxillary and mandibular implants, respectively. The average maxillary mesial and distal bone loss (1-5 yr) was 0.4 mm (SD = 0.8) and 0.2 mm (SD = 0.9), respectively. In mandibles, the average mesial and distal marginal bone loss was 0.3 mm (SD = 0.9) and 0.3 mm (SD = 0.8), respectively.

CONCLUSIONS

Implants placed at the time of extraction and augmented with ePTFE barrier membranes have favorable long-term predictability. On the other hand, long-term evaluation of implant dehiscences and fenestrations augmented with barrier membranes indicates that they have less favorable 5-year survival rates. Membrane augmentation of these may be questioned.

A prospective clinical trial of endosseous screw-shaped implants placed at the time of tooth extraction without augmentation

This prospective clinical trial evaluated 134 implants in 81 patients. The implants were placed at the time of tooth extraction and were not augmented with barrier membranes or graft materials. The implants were placed into good jaw bone anatomy and quality and were restored by dentists familiar with the implant system. Forty-seven implants were followed between 4 to 5 years with a cumulative success rate of 93.3%. Marginal bone levels were measured for 61 patients with 108 implants. The average mesial-distal measurements for maxillary implants at abutment connection were 1.02 mm (SD+/-0.59) and 1.36 mm (SD+/-0.78) at an average of 32 months follow-up. These differences were not significant. The average mandibular mesial-distal measurements at abutment connection were 1.05 mm (SD+/-0.92) and 1.54 mm (SD+/-0.91) at follow-up. These differences were statistically significant (P = 0.0027). Removal of one patient (5 implants) with advanced marginal bone loss from the data provided a marginal bone level of 1.20 mm (SD+/-0.94) at abutment connection and 1.30 mm (SD+/-0.87) at follow-up. These differences were not significant. The results of this study indicate that implants placed at the time of extraction without augmentation or grafting have excellent long-term cumulative success rates.

Histologic findings after implantation and evaluation of different grafting materials and titanium micro screws into extraction sockets: case reports

The purpose of this study was to compare extraction socket healing in 8 patients after implantation with either xenogenic bovine bone (n=5 sites), demineralized freeze-dried bone (DFDBA) (n=3 sites), autologous bone (n=3 sites), or human bone morphogenetic proteins in an osteocalcein/osteonectin carrier (hBMP/NCP) (n=2 sites). Three of the patients received 6 commercially pure micro screws which were fixed into extraction sockets, after which the sockets were implanted with either bovine bone (n=3 sites), DFDBA (n=2 sites) or intraoral autologous bone (n=1 site). Biopsies of the extraction sockets were taken from 3 to 6 months after treatment (average, 4.6 months). For comparison of healing between the implanted materials, histologic evaluation and bone scores were determined. Bone scores of 0 indicated an absence of new bone, with dead implanted bone particles entrapped within connective tissue, while a score of 3 indicated the entire field consisted of vital bone. Biopsies from bovine bone sockets revealed dead implanted particles surrounded by connective tissue. Isolated sections showed host bone in contact with the bovine bone particles. Bone scores ranged from 0 to 3. Biopsies from DFDBA-implanted sites revealed dead particles entrapped with dense connective tissue. The bone scores ranged from 0 to 1. Biopsies from sites implanted with hBMP/NCP revealed a combination of woven and lamellar bone with bone scores of 3. Five of the 6 micro screws were processed and evaluated. One screw was mobile at the time of removal and was not evaluated. Bone scores were used to compare new bone formation adjacent to the micro screws. Bone scores ranged from 0 to 2. A score of 0 indicated non-vital implant material in contact with host bone and connective tissue in contact with implant; 2 indicated vital bone in contact with the majority of the implant surface. Retrieved sockets with micro screws implanted with bovine bone (n=2) demonstrated a connective tissue interface between the screws and the surrounding tissues (bone score 0). The adjacent tissues showed dead bovine particles entrapped within fibrous tissue. Retrieved screws implanted with DFDBA (n=2) were surrounded by connective tissue, with dead bone particles enmeshed within fibrous tissue (bone score 0). The screw implanted with intra-oral autologous bone was primarily surrounded by vital bone with a connective tissue interface (bone score 1). Three implant threads were in contact with bone. The results of this study indicate that bovine bone, DFDBA, and intraoral autologous bone do not promote extraction socket healing. Sockets implanted with hBMP/NCP contained vital woven and lamellar bone. Xenogenic bovine bone and DFDBA did not contribute to bone to micro screw contacts and are not recommended for enhancement of vital bone to implant contacts. Intraoral autogenous bone also does not appear to significantly contribute to bone to implant contacts. Intraoral autologous bone, xenogenic bone, and DFDBA appear to interfere with normal extraction socket healing.

Crown lengthening: the periodontal-restorative connection

Crown lengthening procedures are based on biologic principles that can be determinants for successful treatment. These procedures are fixed on an understanding of the biologic width. A few of the indications for crown lengthening are caries beneath the gingival margin, fractured teeth with insufficient clinical crown exposure, and teeth with excessive occlusal or incisal wear. This article describes flap designs, the use of a new bur probe for precise measurement of clinical crown exposure, and suturing methods for flap stabilization. Clinical documentation of patients with various clinical situations requiring crown lengthening is presented.

Alveolar bone anatomic profiles as measured from dry skulls. Clinical ramifications

The purpose of this study was to evaluate the relationship of alveolar bone morphology to tooth shape and form. 111 dry skulls were evaluated at Baylor College of Dentistry (Dallas, Texas). The skulls were arbitrarily divided into flat, scalloped and pronounced scalloped anatomic profiles according to alveolar bone anatomy. The number of buccal dehiscences and fenestrations was determined for each skull according to their anatomic morphotype. 10 skulls from each group were selected for bone height measurements. The measurements were made with a periodontal probe and ruler from the height of the interproximal bone to the buccal alveolar crest. Kodachrome slides were used to measure mesial-distal tooth width and length from ten skulls from each anatomic category. The average number of fenestrations for each group was 3.5. The mean number of dehiscences for flat and scalloped skulls was 0.5. The average number of dehiscences for pronounced scalloped was 1.2. There were no significant differences when the groups were compared. The mean distance from the height of the interdental bone to the alveolar crest was statistically significant when the groups were compared (flat 2.1 mm, scalloped 2.8 mm, pronounced 4.1 mm) (Tukey, p = 0.05). There were no significant differences when tooth shapes were compared with bone anatomy. Pronounced scalloped anatomic profiles were slightly narrower when compared with the other groups. The observations reported have treatment ramifications when patients with scalloped or pronounced scalloped morphotypes are being considered for dental implant placement.

One-step surgical placement of Brånemark implants: a prospective multicenter clinical study

This prospective longitudinal multicenter study evaluated the clinical outcomes after placement and restoration of one-step Brånemark implants into the maxillae and mandibles of completely and partially edentulous patients. Six surgical treatment centers participated in this study, in which 135 implants were placed into 63 adult patients. All implants were stable after placement. The majority of implants were placed into type B bone with minimal jaw resorption and type 2 bone quality. After implant placement, standard transmucosal healing abutments were firmly placed. The average amount of time between implant placement and prosthetic abutment connection was 170 days in the maxillae and 147 days in the mandibles. To evaluate crestal bone changes caused by implant placement, a periodontal probe was used to measure midbuccally from the top of the implant cylinder to the alveolar crest; in 29 patients, 54 midbuccal bone crest sites were remeasured following prosthetic abutment connection. Crestal bone changes in mandibles and maxillae were statistically and clinically insignificant. Six implants were lost prior to loading and one implant has not been restored. No implants or restorations were lost after loading. At 1 year, the implant success rate was 95.6%. Mesiodistal radiographic measurements from 34 patients were averaged, and changes from prosthetic abutment connection to, on average, 12 months follow-up were compared. The radiographs, which were digitalized, measured from the bottom of the implant cylinder to the most coronal bone in contact with implant thread. For mandibular implants, the mean radiographic bone level at prosthetic abutment connection was 1.07 mm; after loading, it was 1.35 mm. For maxillary implants, the mean radiographic bone height at prosthetic abutment connection was 1.16 mm; after loading, it was 1.36 mm. These changes were not statistically significant. The 1-year outcomes from this patient series indicate that one-step Brånemark implants provide excellent clinical results when placed in patients with good bone quality and quantity.

Clinical and histologic observations of sites implanted with intraoral autologous bone grafts or allografts. 15 human case reports

The cases reported in this paper were treated at 7 different clinical centers and present clinical and histologic observations from 15 patients and 21 human biopsies. The biopsies were taken from extraction sockets or dental implant sites which were grafted with either autologous intra-oral bone (6 sites), demineralized freeze-dried bone (DFDBA) (7 sites), or mineralized freeze-dried bone (MFDBA) (7 sites), or a combination of autologous bone, DFDBA and a barrier membrane (1 site). Six sites were grafted with DFDBA and augmented with expanded polytetrafluoroethylene (ePTFE) barrier membranes. Biopsies for histological evaluation were taken 4 to 13 months after implantation. A bone scoring system of 0 to 4 was used to evaluate the sections for dead implanted particles or the presence of vital bone. A bone score of 3 indicated the presence of dead implant material, blood vessels, islands of cartilage, osteoblasts, and new bone formation. A score of 4 indicated total replacement of the implanted material by the host bone. The average bone score for sites which received autologous bone was 2.33; for DFDBA sites, 0.98; and MFDBA was 0.18. The over-riding histologic characteristic of sites implanted with DFDBA or MFDBA was retention of non-vital graft particles within fibrous connective tissue. Biopsies taken adjacent to the host bed demonstrated incorporation of the allografts (osteoconduction). Sites grafted with autologous bone chips also demonstrated non-vital bone chips surrounded by vital host bone (osteoconduction). Sites which received barrier membranes did not appear to improve or impair bone healing of the augmented sites. Autologous bone chips harvested from within the oral cavity as well as allografts may serve as biologic fillers, but do not apparently contribute to osteoinduction. Autologous bone will eventually be resorbed and replaced by the host. DFDBA and MFDBA are resorbed very slowly and apparently do not contribute to osteoinduction. Allografts apparently are not resorbed by osteoclasts and therefore their continued use around dental implants is questioned.

A prospective multi-center study evaluating periodontal regeneration for Class II furcation invasions and intrabony defects after treatment with a bioabsorbable barrier membrane: 1-year results

The purpose of this prospective multi-center study was to evaluate a resorbable barrier membrane designed for periodontal regeneration. Thirty-one Class II furcations and 30 two- and three-wall intrabony defects were treated by flap debridement and bioabsorbable barrier membrane augmentation. The efficacy of treatment was evaluated in terms of changes in vertical probing depth (PD), horizontal probing depth (HPD), clinical attachment levels (CAL), and recession. Five centers participated in the study. Changes in clinical parameters are reported by individual center and by the average of the centers. All patients had either one molar with a Class II furcation or an intrabony defect. Baseline data were taken on the day of surgery. Post-treatment data were collected at 6 months and 1 year. This report is based on the 1-year findings. The average initial PD for Class II furcations was 6.1 mm. At 1 year the average PD was reduced to 3.6 mm, a 2.5 mm change. These differences were clinically and statistically significant (P < 0.0001). There was an average gain of 2.1 mm of clinical attachment (P < 0.0001) and 0.4 mm of recession (P < 0.04). There was a mean of 1.8 mm change in HPD (P < 0.0001). For intrabony defects, at 1 year there was an average PD reduction of 4.1 mm (P < 0.0001) and a mean gain of CAL of 2.9 mm (P < 0.0001). At 1 year the average recession was 0.9 mm which was statistically significant. When treatment outcomes were compared between centers there were no differences for either group of treated defects. There were differences between centers when baseline PD for furcations and intrabony sites were compared. The results of this study indicate that clinically and statistically significant improvements in PD, CAL, and HPD occurred after treatment of Class II furcations and 2- to 3-wall intrabony defects with the bioabsorbable periodontal membrane.

Flap designs for minimization of recession adjacent to maxillary anterior implant sites: a clinical study

The purpose of this study is to present new flap designs for the prevention of postoperative gingival recession adjacent to maxillary anterior sites that received dental implants. Nine patients received 10 implants in the maxillary anterior region. Gingival morphotypes and smile lines were evaluated prior to implant placement. Gingival probing depths, clinical attachment levels, and recession were recorded at teeth adjacent to implant sites at the initial exam and 3 months after implant restoration. A minimum of 5 mm of crestal bone width was required for implant placement. The labial flaps for healed ridges and implants placed into sockets were extended to or within 1 to 3 mm beyond the alveolar crest. In two sites, transfer of the implant relationships was made to provide the patients with provisional restorations at the time of second-stage surgery. Four patients had implants placed at the time of tooth removal. In these patients, expanded polytetrafluoroethylene barrier membranes were modified, removing the outer rim of material. The inner portion of the material was placed over the implant and the flaps were sutured, leaving the center part of the material exposed. The purpose of using the barrier in this manner was to protect the clot and subsequent granulation tissue formation during the first 2 weeks of healing. The material was removed 2 weeks after surgery. Six implants were placed into edentulous sites. At second stage surgery, flaps were reflected to the alveolar crest, thereby minimizing the potential for gingival recession. Provisional restorations placed at the time of implant uncovering appeared to support the repositioned gingiva. Changes in probing depth, clinical attachment levels, and recession were not statistically or clinically significant. Results of this pilot project suggest that flap designs minimized recession at teeth next to implant sites.

Human demineralized freeze-dried bone: inadequate induced bone formation in athymic mice. A preliminary report

The purpose of this study was to test the osteoinductive properties of demineralized freeze-dried bone (DFDBA) randomly purchased from four commercial bone banks. Twenty-five (25) milligrams of bone from each of the banks was implanted into the hindquarter muscles of athymic mice. Two samples from each of the banks were compared with samples from the other banks. A total of 16 implants were grafted into 8 mice. Two additional mice served as controls. One mouse received an implantation of deactived human cortical bone matrix (DBM) (negative control). The other mouse received an implant of human bone morphogenetic protein/non-collagenous proteins (hBMP/NCP) infused to surface demineralized human cortical bone (positive control). At 21 days the mice were killed, the hindquarters were photographed, and the tissues were prepared for histologic evaluation. Of the 16 commercial DFDBA implants, 12 were available for histologic evaluation. There was no radiographic evidence of bone formation for the DFDBA implanted mice or the DBM implants. Small bone ossicles were scarcely visible in the hindquarters of the mouse which received the hBMP/NCP infused bone. Histomorphometric analysis was used to determine the percentage of new and dead bone. The bone was measured in pixels. The predominant histologic feature of the DFDBA implants was non-vital bone chips with minimal amounts of new bone. The average amount of non-vital bone ranged from 78.4% to 92.5%. There was no evidence of bone formation for the DBM implants. The average amount of bone for the mouse which received hBMP/NCP was 96%. The results of this pilot study indicate that commercially-available DFDBA induced clinically insignificant amounts of bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Replacement of maxillary and mandibular molars with single endosseous implant restorations: a retrospective study

This retrospective report presents findings on 22 patients with 24 implants replacing single molars with implant-supported restorations. Patients with known bruxism habits were not considered for single-molar implant replacement. The patients underwent follow-up for an average of 24 months. The cumulative success rate was 95%, which reflects the loss of one 5 x 6 mm wide implant. Eleven implants were placed in edentulous ridges, and 13 were placed in extraction sockets. Most of the implants were placed in type B and C bone quantity and type 2 and 3 bone quality. All implants were restored on abutments with nonrotating gold cylinders. The occlusion for all restorations was developed to minimize centric contacts and lateral interferences. The frequency of gold retaining-screw loosening was obtained for 21 patients. The gold retaining screws loosened in eight implants between one and three times (38%). No incidence of crown or implant fracture occurred. Within the limits of this study, replacement of single-tooth molars by implant-supported restorations was predictable; however, a high incidence of gold screw loosening was seen.

Variations in bone regeneration adjacent to implants augmented with barrier membranes alone or with demineralized freeze-dried bone or autologous grafts: a study in dogs

A study was performed in two large hound dogs to evaluate the bone-induction potential of demineralized freeze-dried bone (DFDBA) placed into defects adjacent to implants that were placed into extraction sockets. Two implants were untreated controls, two implants received only Gore-Tex Augmentation Membrane (GTAM), two implants received GTAM and autologous bone, and six sites received GTAM and DFDBA. DFDBA was prepared from the long bones of a dog of the same breed as the experimental dogs. P2, P3, and P4 were extracted bilaterally, and buccal defects were created and measured. Twelve commercially pure titanium Brånemark implants were placed. At 12 weeks, clinical measurements were taken and the dogs were sacrificed. The untreated control defects had a mean clinical bone fill of 1.75 mm (37%). Sites treated with autologous bone had a mean of 5.0 mm (95%) of clinical bone fill within the original defects. Sites treated with DFDBA and barriers had 3.8 mm (75%) of bone fill, while sites treated with membranes alone had a mean of 4.2 mm (80%) of bone fill. Histologic evaluation revealed that DFDBA sites had retained nonviable bone chips in 45.4% of the bone matrix, and only 8.3% was lamellar bone. Autologous graft sites had 26.2% retained bone chips within the bone matrix, and 61% percent of the matrix consisted of lamellar bone. For GTAM-only sites, 70.2% of the matrix was lamellar bone and 29.8% was woven bone. Retained DFDBA bone chips were nonviable, occasionally surrounded by woven bone, and appeared to break up and then remineralize without the presence of osteoclastic or osteoblastic activity. Retained autologous bone chips were surrounded and incorporated by the host bone. The autologous bone grafts and DFDBA implants were considered to be osteoconductive. For the three treatment groups, within the defects there were sparse bone-implant contacts. The results indicate that GTAM barriers alone or with autologous bone grafts produced the best clinical and histologic results. DFDBA did not appear to induce bone formation in any of the evaluated specimens.

A comparison of demineralized freeze-dried bone and autologous bone to induce bone formation in human extraction sockets

The purpose of this study was to test the bone-forming capacity of demineralized freeze-dried bone (DFDBA) and autologous bone grafts in extraction sockets. Seven paired sites were grafted with either DFDBA or autologous bone. The sites were reentered between 3 and 13 months for the purposes of obtaining biopsies of the grafted sites and to place endosseous implants. Biopsies from 6 of the 7 grafted sites were evaluated for new bone formation. DFDBA sites revealed the presence of dead particles of DFDBA with no evidence of bone formation on the surfaces of the implanted particles and no evidence of osteoclastic resorption of the bone particles. Biopsies from the 6 autologous sites revealed vascular channels with woven and lamellar bone. Some specimens had retained cortical, non-vital bone chips. These bone chips were undergoing active osteoclastic resorption. The results of this study questions the use of DFDBA as a bone inductive graft material.

Localized ridge augmentation using absorbable pins and e-PTFE barrier membranes: a new surgical technique. Case reports

This paper presents a new surgical technique to promote bone formation in localized alveolar ridge defects. The objective was to regenerate sufficient bone volume for implant placement. The technique is dependent on careful defect debridement and the use of absorbable orthopedic pins, which serve as tent poles and prevent the e-PTFE barrier membranes from collapsing into the defects. The three defects treated with this technique were completely resolved with new bone, and implants were successfully placed into the augmented ridges. Biopsies from the treated sites revealed new bone formation.

The use of e-PTFE barrier membranes for bone promotion around titanium implants placed into extraction sockets: a prospective multicenter study

This multicenter study was conducted to determine the predictability for implants placed into immediate extraction sockets and augmented with e-PTFE barrier membranes. Forty-nine implants were placed in immediate extraction sockets. Initial and final defect measurements and the number of threads exposed were compared. Patients were followed up to 1 year after implant loading. Three implants were lost at the abutment connection surgery. The 1-year survival rate was 93.9%. Twenty barrier membranes became exposed and were removed prior to stage 2 surgery, while the remaining barriers were removed at abutment connection. The average defect bone formation for membrane-retained sites was 4.8 mm, while the average bone formation for sites in which the membranes were prematurely removed was 4.0 mm (P < .0001). At stage 2 surgery there was an average of 0.6 threads exposed (P < .001) for the membrane-retained sites and 2.6 threads for the early removal sites (NS). Forty-five pairs of nonstandardized radiographs were evaluated for bone loss after implant loading (average 7.5 months). The mesiodistal bone loss averaged 0.72 mm. Within the limits of this study, e-PTFE membranes will promote clinically and statistically significant amounts of bone around immediately placed implants. Retention of e-PTFE barriers until stage 2 surgery improves the amount of bone promoted around the implants.

Swimming onward: the future of aquatic rehabilitation

This article is a summary of the current state of the art in aquatic rehabilitation. It discusses affordable treatment modalities to enhance compliance. Fundamental research is lacking in aquatic rehabilitation as well as the availability of trained resource people. There is much to be gained through further development of aquatic methods, facilities, and communication pathways between medical professionals and the external world of aquatic community-based activities.

The biologic aspects of hydrotherapy

The aquatic environment has a long and documented history in rehabilitation. This environment causes significant biologic effects which are applicable to many rehabilitative problems. Both immediate and delayed physiologic effects are noted in the immersed human and involve nearly all the basic homeostatic mechanisms. Particularly affected are the cardiovascular, renal, and pulmonary systems. The fundamental cardiovascular process is an increase in venous return with consequent increases in right atrial pressure, stroke volume, and cardiac output. The net effects upon the renal system are decreased anti-diuretic hormone (ADH) and aldosterone production, causing increased sodium and potassium excretion and consequent diuresis. The effects upon the respiratory system result from hydrostatic compression of the thorax coupled with increased intrathoracic blood volume. Both increase the work of breathing and decrease expiratory reserve volume. Effects upon muscle circulation, joint unloading, and general conditioning are also potentially useful in rehabilitation. This article reviews these effects and the literature support for these biologic changes.

Delivery of primary care to the physically challenged

The specialty of physical medicine and rehabilitation evolved beyond conventional medical views to include consideration of the needs of the physically disabled person's function and quality of life. A care delivery system of medical rehabilitation programs and services then evolved. Recently, the United States' health care system has been recognized as being deficient in meeting the on-going health care needs of the physically disabled after they have completed medical rehabilitation needs. We discuss the history of the health care needs of the physically challenged and we examine current issues of need and delivery of services. We also describe an innovative model program designed to meet those needs.

Treatment of mandibular 3-wall intrabony defects by flap debridement and expanded polytetrafluoroethylene barrier membranes. Long-term evaluation of 32 treated patients

The purpose of this study was to evaluate the healing potential of deep, primarily 3-wall intrabony defects which were treated by flap debridement and expanded polytetrafluoroethylene (ePTFE) membranes and followed for extended time periods. All of the treated defects were in the mandibular arch. Thirty-two patients were treated and re-examined at an average of 3 years 5 months. Twenty-four of these patients had re-entry procedures at the second examination. Sixteen of these patients were examined a third time at an average of 4 years 3 months. The patients were evaluated for changes in probing depth (PD), clinical attachment level (CAL), recession, changes in crestal resorption, and defect bone fill. The paired t-test for related samples was used to test for differences between examinations. Between Exams 1 and 2 there was a statistically significant reduction of pocket depth (3.8 mm), gain in clinical attachment level (4.2 mm), and an increase in recession (-1.2 mm). For the 24 patients who had re-entry procedures there was an average defect fill of 4.3 mm (P < 0.0001) and 0.33 mm of crestal resorption (P < 0.0001). The 16 patients who were examined 3 times sustained decreases in PD, gains in CAL, and recession recorded at the second examination. These changes were statistically significant at Exam 3. The results of this study demonstrate that deep, 3-wall intrabony defects treated by debridement and ePTFE barrier membranes will have significant decreases in PD, gains in CAL, recession, decreases in crestal resorption, and gains in bone fill.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodontal regeneration updated

Techniques in treating periodontal disease are discussed to provide insight about which technique fits each clinical situation. New developments provide possible regeneration of new cementum, periodontal ligament and alveolar bone, resulting in a new periodontal attachment.

A comparison of ePTFE membranes alone or in combination with platelet-derived growth factors and insulin-like growth factor-I or demineralized freeze-dried bone in promoting bone formation around immediate extraction socket implants

The purpose of this study was to compare bone promotion around implants which were augmented with ePTFE membranes alone or in combination with cortical demineralized freeze-dried bone (DFDB) or the combination of platelet derived growth factor-BB (PDGF) and insulin like growth factor I (PDGF/IGF-I). Membranes were placed over titanium implants which had been inserted into fresh extraction sockets with large buccal dehiscences. Twenty-four implants were placed in 4 dogs. At 18 weeks clinical bone height measurements were taken, the animals were sacrificed, and all specimens retrieved for histologic evaluation. Clinically, a significant gain in bone levels was present in both the ePTFE membrane alone group (P < 0.005) and PTFE plus PDGF/IGF-I group (P < 0.01), but not in the PTFE plus DFDB group. Results from histometric measurements revealed an approximately 2-fold increase in the percentage of implant surface in contact with bone, area of bone adjacent to the implant surface, and in the total length of the implant surface in contact with bone in the dehiscence defects treated with ePTFE plus PDGF/IGF-I compared to the defects receiving ePTFE membranes alone (each P < 0.05). The response to the DFDB was highly variable and it did not significantly improve the efficacy of the PTFE membranes for any parameter measured. The distance from the outer surface of the new bone to the implant surface was statistically significant for ePTFE membranes alone and membranes plus PDGF/IGF-I. The results demonstrated that clinically, ePTFE membranes alone or ePTFE membranes with PDGF/IGF-I were equally effective in promoting bone growth around the implants. Histologic measurements demonstrated that sites treated with ePTFE membranes plus PDGF/IGF-I had the highest bone density compared with sites which received ePTFE membranes alone or with ePTFE membranes and DFDB. The results of this study question the use of DFDB and support the use of ePTFE membranes alone or with PDG-F-BB/IGF-I as potential methods of promoting bone formation around dental implants.

Guided tissue regeneration for implants placed into extraction sockets: a study in dogs

Twelve 10 mm implants were placed into immediate extraction sockets in dogs. Six implants were isolated with PTFE membranes and 6 sites served as controls. Standardized clinical measurements were taken at test and control sites. At 18 weeks the dogs were anesthetized and flaps were laid for the purpose of obtaining clinical measurements. The average gain of bone around augmented implants was 2.6 mm, while control sites had an average bone gain of 1.0 mm. Ridge width adjacent to augmented sites increased by 1.2 mm and control sites had an increased width of 0.6 mm. Histologic evaluation of test and control specimens showed greater bone formation around augmented implants. Implants augmented with PTFE membranes had clinically significant amounts of bone regeneration when compared with controls.

Regeneration procedures: grafting materials, guided tissue regeneration, and growth factors

Flap debridement, bone grafting, and guided tissue regeneration have the capacity of regenerating bone, periodontal ligament, and cementum. Alloplastic materials are used to fill periodontal defects, and healing occurs by repair. While varying amounts of new bone may form with allografts, a long junctional epithelium is usually the mode of attachment. Flap debridement has been reported to successfully treat multiple walled intrabony defects. Healing results in bone regeneration. However, there is probably a long junctional epithelium adjacent to the root. Defects treated by guided tissue regeneration have been demonstrated to heal with new cementum, periodontal ligament, and bone. Recently, growth factors have been discussed as a possible means of enhancing wound healing.

A longitudinal study comparing scaling, osseous surgery and modified Widman procedures. Results after one year

The purpose of this study was to compare, longitudinally, the effectiveness of scaling and root planing, osseous surgery, and the modified Widman procedures. The study was carried out in a private practice setting. Sixteen adult patients with moderate to advanced adult periodontitis were treated with initial scaling and oral hygiene procedures. Posthygiene data were used for comparison of changes in probing depth, clinical attachment levels and gingival recession. The initial examination data were used to compare changes in plaque and gingival indices. Frequency distributions were used to compare changes that occurred at individual sites. At one year, plaque and gingival indices were significantly reduced when compared with the initial examination. At one year, shallow pockets (1-3 mm) were reduced when compared to posthygiene. Four- to six-millimeter pockets were significantly reduced by the three procedures. Osseous surgery and modified Widman had significantly greater pocket reduction when compared with scaling. For pockets greater than 7 mm, osseous surgery and the modified Widman had significantly greater reduction when compared with scaling. For pockets 1-3 mm at one year osseous surgery had significantly greater clinical attachment loss when compared with scaling. For 4-6 mm pockets at one year, the three procedures had slight gains in clinical attachment levels. The results were similar for pockets with greater than 7 mm. Interproximal soft tissue craters were measured for six postoperative weeks. Initially, the modified Widman had a higher percentage of soft tissue craters when compared with osseous surgery. At six weeks, however, there were no significant differences when the surgical procedures were compared. Recession was measured at each examination. Recession for 1-3 mm pockets at one year was greater for osseous surgery when compared with scaling and the modified Widman. Recession for 4-6 mm and greater than 7 pockets was greater for the surgical procedures than scaling. The results from this study indicate that with three-month maintenance recalls, both the modified Widman and osseous surgery are effective for pocket reduction, and each will produce a slight gain of clinical attachment over one year. Scaling was effective at maintaining attachment levels but was not as effective in reducing pocket depth.

Personality differences and stressful life events. Differences between treated periodontal patients with and without maintenance

The purpose of this study was to determine whether personality differences exist between patients who have had periodontal therapy and continued in maintenance compared with those who have had periodontal therapy and no maintenance. In addition, an attempt was made to determine whether there were differences in reactions to stressful life events among the 2 groups of patients. Patients were evaluated for personality differences using the adjective check list. A background questionnaire was used to gather personal data and information pertinent to stressful life events. The maintained group had a more positive image of themselves. They had higher achievement, endurance and affiliation scores than did the patients without maintenance. The unmaintained group had higher negative aggression scores, a higher incidence of stressful life events, and less stable personal relationships in their lives.

Root isolation for new attachment procedures. A surgical and suturing method: three case reports

A surgical and suturing method is described for the subgingival placement of Gore-tex periodontal material during new attachment procedures. The periodontal material isolates the root surface from epithelium and gingival connective tissue. Three cases were treated. Clinical new attachment was evident from clinical probings and reentry. The term "open probing new attachment" describes the type of tissue that was evident at reentry after treatment of a Class III furcation. A combination of new bone and "open probing new attachment" was evident after one-wall defects were treated adjacent to a mandibular cuspid. A two-wall defect was treated and biopsied three months later. A reference notch was placed 1 mm coronal to the apical aspect of the defect. Histologic examination of the biopsy showed new bone, cementum and periodontal fibers coronal to the notch. Clinical and histologic new attachment was achieved using the technique for root isolation. The long-term predictability and stability of this type of new attachment is not known at this time.

Clinical and volumetric analysis of three-wall intrabony defects following open flap debridement

Fourteen defects were treated with flap debridement procedures using the Prichard principle of epithelial exclusion. Six defects were considered to be medium in width (3-4 mm), seven defects were wide (greater than 4 mm), and one defect was narrow (1-2 mm). The parameters studied were changes in gingival and plaque scores, attachment levels, and bone scores. All defects were reentered 9 to 16 months after surgery and changes between the pretreatment and posttreatment bone levels were recorded. The mean gain in probing attachment level was 2.76 mm. The mean amount of defect fill measured from models was 2.56 mm, while the mean defect fill from direct measurements was 3.26 mm. The percentage defect fill measured from study models was 61%. Crestal resorption was 9.7%. The average change in defect volume unadjusted for crestal resorption was 61.8 cu mm. Seven defects had a 50% or greater decrease in defect volume, while seven defects had less than a 50% change. Intrabony defects where calculus is present on the involved tooth surface prior to therapy will repair with substantial amounts of bone as a result of open debridement.

Periodontal treatment without maintenance. A retrospective study in 44 patients

This study presents our findings on 44 patients who were treated for periodontal disease and for varying reasons elected not to participate in the maintenance aspect of periodontal care. All patients were initially given intensive instructions in personal oral hygiene, along with initial scaling and root planing. Each patient had two or more quadrants of pocket reduction therapy. Tooth mortality revealed a mean annual adjusted tooth loss rate of 0.22 (4.7%). Between examinations, breakdown in the health status of furcations was noted. Mean probing depth scores at the second examination showed no significant differences from the first examination scores. Measurements of bone levels revealed a worsening of bone scores between examinations. The results of this study show that periodontal therapy without maintenance is of little value in terms of restoring periodontal health.

Hypertrophic burn scarring: control of chest deformities with a new device

Despite the use of conventional therapeutic techniques, increasing kyphosis, chest restriction and worsening burn scar hypertrophy occurred in a 9-year-old boy with burn trauma. In an attempt to alleviate these problems a device consisting of a plastizote molded 2-piece body jacket which incorporates a full neck and chin conformer was fabricated. After the child had worn the device for approximately 6 1/2 months, shoulder and neck range of motion was full, chest expansion was normal for his age, and stature was fully erect.

Union impact on wages and fringe benefits of hospital nonprofessionals

Union effects on the wages and fringe benefits of nonprofessionals are estimated for a sample of hospitals in three midwestern states. Survey questionnaire, personal interviews, and published data are combined to determine both the compensation gains of unionized workers and the "spillover" effects on nonunion workers in unionized hospitals. The results of this analysis suggest that overall union effects on total compensation are in the order of 6 to 7 percent for both groups.

Untreated periodontal disease: a longitudinal study

Thirty diagnosed but untreated patients with moderate to advanced periodontal disease were examined a minimum of two times. The examination time intervals ranged between 18 and 115 months. 2. A total of 83 teeth were lost between examinations. 3. Excluding a patient who lost 25 teeth, a total of 58 teeth were lost. The adjusted tooth loss was 0.61 tooth per patient per year (or 0.36 with the elimination of 22 "hopeless" teeth). 4. The mandibular and maxillary molars had the greatest percentage of tooth loss between examinations. 5. All 29 patients completing the study had progessive increases in pocket depth during their time in the study. Increases in the mean annual pocket depths per tooth per patient varied from 0.24 millimeter per year to 2.46 millimeters per year. 6. The disto-lingual and mesio-lingual interproximal surfaces had the greatest increases in surface pocket depths. The lingual and buccal surfaces had the smallest increases in pocket depth. 7. The rate of increase in pocket depths was less in patients over 44 years of age. 8. The teeth which were lost had greater initial pocket depths and mobility scores than those which were present at both examinations. 9. There was no correlation between increases in pocket depth and changes in mobility. 10. All 29 patients showed radiographic evidence of progressive bone resorption between examinations. The posterior segments of the mouth had the largest amounts of bone loss between the first and last examinations.