A prospective 2-year clinical evaluation of overdentures attached to nonsplinted implants utilizing ERA attachments.

Edentulism is a major oral healthcare issue for an ever-increasing older population in the United States. Most previous studies examined the success of overdentures supported by splinted implants utilizing clip bars and other types of attachments. This longitudinal study of 10 consecutive patients involves mandibular overdentures supported by nonsplinted implants with ERA attachments. Two-year results indicate that nonsplinted implants can be successfully used with ERA attachments to support overdentures. Each patient reported increased satisfaction with comfort, chewing, retention, and phonetics with the implant-assisted ERA-retained overdenture.

A comparative study utilizing open flap debridement with and without enamel matrix derivative in the treatment of periodontal intrabony defects: a 12-month re-entry study.

BACKGROUND: Previous studies have demonstrated that enamel matrix derivative (EMD) has the ability to improve clinical parameters when used to treat intraosseous defects. The purpose of the present study was to compare at 12 months postsurgery sites treated with open flap debridement (OFD) alone to those treated with OFD and EMD. METHODS: Twenty-three subjects with at least 2 intrabony defects were chosen. Fifty-three defects received EMD in conjunction with OFD. Thirty-one defects in these same 23 subjects were treated with OFD alone. Stents were fabricated to serve as fixed reference points. Re-entries were performed at least 1 year after initial surgery. Soft tissue measurements were recorded prior to initial surgery and prior to re-entry for gingival (GI) and plaque (PI) indices, probing depth (PD), gingival margin position, and clinical attachment level (CAL). Hard tissue measurements were recorded during the initial and re-entry surgery for level of crestal bone and depth of defect. Statistical analysis was conducted using the method of generalized estimating equations to determine changes in GI, PI, PD, CAL, fill of the osseous defect, and crestal resorption. Percent of defect fill was also calculated. RESULTS: In all categories, treatment with EMD (test) was superior to treatment without EMD (control). Average PI and GI were not significantly different either initially or prior to re-entry. The average PD reduction was 2.7 mm greater with EMD than controls. The average CAL gains were 1.5 mm greater, and the average fill of osseous defect 2.4 mm greater with EMD than controls. The average percent of defect fill after adjusting for crestal bone loss was more than 3 times greater for EMD versus control-treated sites (74% defect fill with EMD versus 23% defect fill for control sites). CONCLUSIONS: This study indicates that treatment of periodontal intraosseous defects with EMD is clinically superior to treatment without EMD (open flap debridement) in every parameter evaluated. Re-entry data demonstrate that percent fill of osseous defects treated with EMD compares favorably with the treatment results utilizing bone grafts or membrane barriers, according to published literature.

Histologic response to intraligament injections using a computerized local anesthetic delivery system. A pilot study in mini-swine.

BACKGROUND: Intraligamentary (periodontal ligament) injection has been used to locally control pain with minimal anesthetic dose. The purpose of the present study was to determine the histologic effect of using a computer-controlled local anesthesia delivery system (CCLADS) for the administration of a periodontal ligament injection in the mini-swine model system. METHODS: Thirty-two sites in 3 mini-swine pigs with healthy periodontium were selected. Each site was notched on the mesial-lingual line angle of the tooth to allow a reference for needle placement and provide a histologic marker. An anesthetic cartridge was used with a 30-gauge needle attached to the handpiece of the CCLADS. This provided a controlled flow rate for 2 minutes. The control sites were treated with the same needle in place for 20 seconds. The animals were sacrificed and provided observation periods of 1 hour, 1, 4, 7, 21, and 49 days. Specimens were stained with hematoxylin and eosin and trichrome. RESULTS: Twenty-four hours after injection, limited localized inflammation was present. By 7 days, the ligament appeared within normal limits. Apical migration of the junctional epithelium extended to the apical limit of the notch and was similar in test and control specimens. CONCLUSIONS: Within the limits of this study, the histologic results showed that tissue responses following intraligament injections using a CCLADS demonstrated limited inflammatory responses within the first 24 hours, which abated by 7 days postinjection. Similar migration of the junctional epithelium was seen in test and control specimens and was probably related to tooth injury rather than anesthetic injections. Further investigations are warranted using CCLADS to determine whether clinical benefits will translate in the human model system.

Histologic and clinical comparison of bilateral sinus floor elevations with and without barrier membrane placement in 12 patients: Part 3 of an ongoing prospective study.

In 1993 the Department of Implant Dentistry at New York University College of Dentistry began a long-term clinical, histologic, histomorphometric, and radiographic study of the sinus elevation procedure. One of the parameters under evaluation in this study is the effect of barrier membrane placement on the creation of vital bone in the grafted sinus cavity. This report presents a histologic and histomorphometric evaluation of healing with and without the placement of an expanded polytetrafluoroethylene (e-PTFE) barrier membrane over the lateral window at the time of sinus grafting. The data were collected from 12 patients who underwent bilateral sinus elevation surgery. In each of these 12 patients the same grafting material was used in both sinuses, making the presence or absence of an e-PTFE barrier membrane the only controlled variable. Under the conditions of this study, the results indicate that (1) placement of the barrier membrane tends to increase vital bone formation; (2) placement of a barrier membrane has a positive effect on implant survival; and (3) membrane placement should be considered for all sinus elevation procedures.

Comparison of bioactive glass synthetic bone graft particles and open debridement in the treatment of human periodontal defects. A clinical study.

The purpose of this study was to compare the repair response of bioactive glass synthetic bone graft particles and open debridement in the treatment of human periodontal osseous defects. Fifty-nine defects in 16 healthy adults were selected. Each patient had at least 2 sites with attachment loss of at least 6 mm with clinical and radiographic evidence of intrabony or furcation defects. One to 3 months after cause-related therapy (oral hygiene instructions, scaling and root planing), the following measurements were recorded prior to surgery: probing depths, clinical attachment level, and gingival recession. Each defect was surgically exposed and measurements made of the alveolar crest height and base of osseous defect. The test defects were implanted with bioactive glass. The other sites served as unimplanted controls. Flaps were sutured at or close to the presurgical level. Radiographs and soft tissue presurgical measurements were repeated at 6, 9, and 12 months. At 12 months all sites were surgically re-entered to record osseous measurements. At the 12-month evaluation, significantly greater mean probing depth reduction was noted in the bioactive glass group compared to the controls (4.26 mm versus 3.44 mm; P = 0.028). Clinical attachment level gain was significantly improved (P = 0.0004) in the bioactive glass sites (2.96 mm) compared to the control sites (1.54 mm). There was significantly less gingival recession in the bioactive glass sites (1.29 mm) compared to the control sites (1.87 mm). Defect fill was significantly greater in the bioactive glass sites (3.28 mm) compared to the control sites (1.45 mm). Defect depth reduction was significantly greater in the bioactive glass sites (4.36 mm) compared to the control sites (3.15 mm). In conclusion, bioactive glass showed significant improvement in clinical parameters compared to open flap debridement.

Sinus floor elevation using anorganic bovine bone matrix (OsteoGraf/N) with and without autogenous bone: a clinical, histologic, radiographic, and histomorphometric analysis--Part 2 of an ongoing prospective study.

One of the goals of the sinus elevation procedure is the creation of vital bone to effect the osseointegration of dental implants placed in the posterior maxilla. With this goal in mind, in 1993 the Department of Implant Dentistry at New York University College of Dentistry began a long-term clinical, histologic, histomorphometric, and radiographic study of the sinus elevation procedure. The primary parameters included the effects of graft material selection, time allowed for graft maturation, and the effect of barrier membrane placement on the creation of vital bone in the sinus cavity. The effects of these and other parameters on implant survival rates were also to be evaluated. This paper reports the data collected on a subgroup of 113 sinus elevations that used anorganic bovine bone matrix (OsteoGraf/N) alone or in combination with autogenous bone and/or demineralized freeze-dried bone as a graft material. This is the second in a proposed series of papers that will result from this ongoing research project. The results of this study indicate that: OsteoGraf/N appears to be an effective graft material with a 98.2% implant survival rate to date: vital bone formation increased with time; vital bone formation increased moderately when demineralized freeze-dried bone allograft was added, and increased substantially when intraoral autogenous bone was added or when an expanded polytetrafluoroethylene membrane was used; and the increased height achieved by the procedure was stable over a 3-year period. Because of the high overall implant survival rate, it was not possible to determine the relationship between vital bone formation or membrane usage and implant survival.

Human histologic evaluation of HTR polymer and freeze-dried bone allograft. A case report.

This case report compares the results of placement of HTR (Hard Tissue Replacement Synthetic Bone) and freeze-dried bone allograft (FDBA) in the same patient. 2 notches were made in each of 6 teeth, 1 at the gingival margin and the other at the most apical level of calculus. Soft tissue responses with both materials included probing depth reduction, gingival shrinkage and gain in clinical attachment. Histological sections of block extraction sites 30 months after placement of either material showed no signs of new attachment. Little or no inflammation was present with both materials. There was also an absence of all FDBA particles which assumes complete resorption of this material prior to 30 months. Gingival shrinkage resulted in the exposure of the gingival and calculus notch in all FDBA treated sites. Gingival epithelium was found adjacent to the gingival notch in all HTR treated sites. The calculus notch in HTR treated sites was lined by junctional epithelium with connective tissue and bone opposing the adhesion. HTR particles were present and surrounded by connective tissue or bone. HTR appears to serve as a scaffold for new bone formation when in close contact with alveolar bone.

Histologic evaluation of a sinus elevation procedure: a clinical report.

A histologic assay of the grafting material associated with the sinus elevation procedure would provide insight into the quality and quantity of vital bone at the implant-bone interface. This case report documented for the first time the sequential healing process of a sinus graft in the same patient at 4, 8, 12, and 20 months. Histology of trephine-obtained core samples showed that in a sinus grafted with a mixture of xenograft (80%) and autograft (20%), 12 to 20 months was required for remodeling to vital bone. The study also demonstrated that a significant amount of vital, mature bone was generated by this procedure. Quantification of the resulting bone and comparison with other grafting techniques should be the next phase of continuing research efforts.

Modified coronally positioned flap for obtaining new attachment in Class 2 and 3 furcation defects. Part I: Rationale and surgical technique.

A new technique, the modified coronally positioned flap procedure, is described for treatment of Class 2 and Class 3 molar furcation defects in conjunction with barrier membranes. This technique is designed to minimize barrier exposure during the healing phase and to cover and protect the newly formed granulation tissue following barrier removal. Examples are presented and discussed, and modifications for varying situations are described. The modified coronally positioned flap technique is applicable for use with nonresorbable and resorbable membranes.

Use of the carbon dioxide laser in retarding epithelial migration: a pilot histological human study utilizing case reports.

Predictable regeneration of tooth-supporting tissues lost to periodontal disease is the aim of periodontal therapy. Often the result of conventional treatment is healing with a long junctional epithelium along the root surface and little regeneration of the complete attachment apparatus. The purpose of this pilot study was to evaluate whether de-epithelialization with a CO2 laser at the time of flap surgery and at 10-day intervals over the first 30 days of healing has the potential to enhance the formation of a connective tissue attachment. Six mandibular incisors in two patients were selected for the study. Each patient received oral hygiene instruction and initial therapy prior to surgery. The teeth were splinted together, open flap debridement was performed on all teeth, a notch was placed on the roots at the height of the crest of the alveolar bone, and the flaps were sutured in place. The test side received controlled de-epithelialization of the outer (oral) gingiva with the carbon dioxide laser, and the inner gingival flap. The de-epithelialization was repeated on the test side at 10, 20, and 30 days postsurgically. Controls received open debridement only. Block sections were taken at 90 days and processed for histologic analysis. The results showed that for both patients, junctional epithelium (JE) was formed on both test and control teeth. In all control teeth, the JE extended the entire length of the root to the base of the reference notch.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodontal regeneration.

This paper reviews the current clinical and histologic literature in the field of periodontal regeneration. Various procedures and agents that have been used to attain regeneration and new attachment are reviewed, including open flap debridement, root conditioning, the use of bone grafts and bone substitutes, guided-tissue regeneration, coronally positioned flaps, and a combination of these. Future directions for clinical and research efforts are discussed, with emphasis on growth factors, their delivery, and enhancement of the healing response. Literature identifying factors that will aid in the regeneration of lost periodontium is reviewed and critiqued.

Healing of human suprabony lesions treated with guided tissue regeneration and coronally anchored flaps. Case reports.

Teflon membranes were interposed between soft tissue flaps and roots in 4 human suprabony lesions affecting the mandibular incisor teeth in 1 volunteer patient. 4 suprabony lesions affecting the mandibular incisor teeth were used as comparisons in a 2nd patient. All roots were debrided using ultrasonic and manual instruments and the most apical positioned calculus/site on the facial surface was notched. Flaps were sutured as coronally as possible using orthodontic brackets as anchors. Tissue blocks were removed 2 to 3 months after procedures and the facial aspects of all teeth were examined histologically. New attachment in the form of new "cementum with functionally oriented fibers" was seen within the calculus notch in 3 out of 4 membrane-treated sites and immediately apical to the notch at 1 site. The 4 comparison sites showed no evidence of new attachment within or adjacent to the notch. Rather, the gingival margins were located apical to the notch. Our observations suggest that guided tissue regeneration techniques improved coronal attachment responses in human suprabony lesions within the sample described.

Human clinical and histologic responses to the placement of HTR polymer particles in 11 intrabony lesions.

Eleven intrabony periodontal lesions in five volunteer patients received surgical debridement followed by site implantation of a porous particulate polymeric composite (HTR polymer). These patients were observed over time periods varying from 4 weeks to 26 weeks. At the end of the individual observation periods, treated sites were surgically removed in block for histologic analysis. Clinical observations indicated a reduction in pocket depth following treatment which consisted of both gingival recession and gain in clinical closure. No untoward effects were observed clinically in any treated patient during the observation periods. Histologic responses varied from gain in closure by epithelial adhesion to new attachment of varying magnitude. Such varied responses were seen within the same patient and between patients. Graft particles were present at sites from 4 weeks to 26 weeks after implantation and were surrounded by connective tissue capsules. At the periphery of some particles, limited bone formation was present. The alveolar bed was remodeling, at times surrounding specific particles. In our sample, HTR polymer, therefore, appeared to be a well tolerated synthetic graft material when implanted in human intrabony lesions.

Histologic and clinical responses to porous hydroxylapatite implants in human periodontal defects. Three to twelve months postimplantation.

Twelve intrabony periodontal lesions in three volunteers received surgical debridement followed by site implantation of porous hydroxylapatite implants. These patients were followed over a total of a 1-year observation period. Blocks of treated sites were surgically removed at 3 months, 6 months and 12 months after implantation. Clinical observation indicated a reduction in pocket depth consisting of both recession and clinical gain of attachment. No ill effects were observed. Histologic examination of the treated sites showed ossification of the implant pores and the implant periphery as early as 3 months after implantation, which became pronounced 12 months after placement. At times, peripheral ossification linked with crestal osseous seams. This ossification occurred in the presence of an adjacent root covering, long junctional epithelium, and thus there was no new attachment. On the other hand, this graft material offers the potential of increasing new bone mass within a human intrabony lesion.

Healing responses of human intraosseous lesions following the use of debridement, grafting and citric acid root treatment. II. Clinical and histologic observations: one year postsurgery.

This report details histologic healing responses at intrabony sites within two patients about 1 year after surgery. Treatment consisted of open flat debridement of the lesions. At specific sites, augmenting procedures such as autogenous grafts, allografts, synthetic grafts and citric acid root treatment were utilized. In addition, notches were made through calculus prior to root planing at specific root surfaces. These notches were placed at varying distances from the base of the lesion. Patients were followed postsurgically with frequent maintenance visits. Block sections were removed at the end of the experimental period. Clinical reduction in pocket depth was noted at all treated sites. This reduction consisted of limited pocket closure, marginal gingival recession and repocketing. Histologically, all specimens showed evidence of repair. The most mature repair appeared at sites treated with debridement and autogenous grafts. "Regeneration" of lost periodontal attachment was demonstrated by evidence of cementogenesis, osteogenesis and the presence of functionally oriented ligaments. However, the coronal regeneration appeared spatially limited. Allografts showed a similar, but less mature healing response. Synthetic graft material acted essentially as a "filler" within the defect. Citric acid root treatment did not demonstrate clear evidence of augmentation of the repair process. Of particular note in these human specimens was further histologic demonstration that "regeneration" potential apparently can only take place in close proximity to histologically viable periodontal ligament cells which may act as "donor sites" for coronal "regeneration" of lost periodontal attachment. This histologic response was observed regardless of treatment modalities used.

Healing responses of human intraosseous lesions following the use of debridement, grafting and citric acid root treatment. I. Clinical and histologic observations six months postsurgery.

Three block sections of treated human intraosseous lesions within one individual are presented. These lesions were debrided, filled with autogenous grafts and at two sites the root was treated with citric acid. The treated sites were lightly root planed once a month and the blocks were removed 6 months after surgery. In addition, the root accretions within two lesions were notched with a bur prior to root planing in order to positively identify the position of these root accretions in the histologic sections. Clinically, the lesions closed by marginal shrinkage and limited pocket closure. Histologically, regeneration of new cementum, osteogenesis at bone and graft spicule seams and reformation of functionally oriented ligament fibers were present at sites within lesions where accretions had covered the root. Such a healing phenomenon was observed close to the base of the lesions and seemed to be related to this spatial configuration rather than to the notching of the root itself. No specific increased healing responses could be attributed to citric acid root treatment. Thus, "regeneration" of new attachment is possible within human intraosseous lesions even at root sites previously covered by accretions. However, such responses seem to be limited to areas near the base of the intraosseous lesion.

Human clinical and histologic responses to Durapatite implants in intraosseous lesions. Case reports.

The healing response following implantation of a nonresorbable ceramic (durapatite) into human periodontal osseous defects was evaluated clinically and histologically. Four tooth-containing blocks were obtained from four patients who had received durapatite implants in osseous defects, each exceeding 4 mm in depth. Each patient was seen for 5 to 13 postsurgical maintenance visits. Teeth in block section were removed between 8 weeks and 8 months postgraft surgery. Clinical evaluation of the repair process demonstrated that pocket depth decreased in all four cases. Histological evaluation of the repair process showed no indication of new periodontal attachment, osteogenesis or cementogenesis, in the host tissues adjacent to the graft particles. Pocket closure appeared to occur by means of a long junctional epithelium and connective tissue adhesions. There was minimal or no evidence of inflammation in all sections associated with the implant. The graft material therefore acted as a biocompatible foreign body within the gingival tissue.

Periodontal healing following open debridement flap procedures. II. Histologic observations.

Four tooth-containing blocks were obtained from patients being treated for infraosseous lesions of significant depth as part of their periodontal therapy. Treatment consisted of open flap debridement and professional cleansing at least every 4 weeks. Teeth in block were removed for histologic study 4 to 6 months after surgery. Histologic evaluation of the repair process showed pocket closure by epithelial and connective tissue adhesions in the form of an elongated junction epithelium, beneath which parallel-oriented fibers adhered to the root for a limited distance. Apical to this adhesion, functionally inserted fibers were present. Since no cementogenesis was seen at these latter areas, it must be assumed that the inserted fibers were present before the surgery and were not significantly affected by the procedure. No significant evidence of crestal osteogenesis was noted. However, comparison of the clinical osseous profile recorded at the time of surgical debridement with the flat crest seen in two of our cases histologically, suggests that significant crestal resorption had taken place postsurgically in some of these lesions.