Implants In Edentulous Patients Research Articles

Meko podlaganje imedijatne totalne proteze - prikaz slučaja

Introduction: With the placement of dental implants in edentulous patients, creating and adapting immediate dentures is crucial to allow patients to perform basic physiological functions during the osseointegration period without affecting implant healing. This report presents a case of direct soft lining of immediate complete dentures following implant placement. Case Report: Six dental implants were inserted in the upper jaw, while the patient retained natural teeth in the lower jaw. An immediate complete denture was fabricated and adjusted for the upper jaw. The prosthesis base was prepared and processed to accommodate soft lining material. Adhesive was applied to the prepared base, followed by silicone application for soft fitting onto the prosthesis base, which was then inserted into the patient's mouth. After three minutes, the denture was removed, and soft lining treatment of the immediate complete denture was completed. Conclusion: Direct soft lining facilitated patient adaptation to the immediate prosthesis and supported safer healing and osseointegration until definitive work could be completed. The addition of a soft silicone layer reduced pressure on the residual alveolar ridge and improved adhesion of the immediate prosthesis.

Survival Rates and Clinical Outcomes of Implant Overdentures in Old and Medically Compromised Patients.

Studies on the survival rate of implant overdentures in medically compromised patients are limited because most studies exclude patients with systemic diseases affecting implant prognosis. This retrospective study aimed to evaluate the survival rate and clinical outcomes of dental implants used for overdentures in medically compromised patients. A total of 20 patients (9 men, 11 women; mean age: 67.55 ± 6.84 years, range: 53–81 years) were included. Fourteen patients had more than two systemic diseases, and nine patients had more than three systemic diseases. The mean follow-up period was 39.05 months. Of the 60 implants, 2 failed, resulting in an implant survival rate of 96.6%. No statistical differences were found in implant survival rates according to sex, age, implant diameter, restored arch, or opposing dentition (p > 0.05). A significant difference in mean marginal bone loss (MBL) was noted for restoring the arch (p = 0.022) and opposing dentition (p = 0.036). Implants placed in the mandible and with opposing removable partial dentures and complete dentures showed lower mean MBL. No significant differences in implant MBL were observed in terms of age, sex, or implant diameter (p > 0.05). Favorable clinical outcomes can be expected from implant overdentures using two or four implants in edentulous patients with systemic diseases by ensuring that the patients have a sufficient healing period and regular checkups.

Primary and Secondary Stability of Extrashort (4-mm) Implants in the Edentulous Mandible: Preliminary Results of a Prospective Clinical Trial

To compare the primary and secondary stability of conventional (≥ 8-mm) and extrashort (4-mm) implants in edentulous patients using different methods of assessment. Patients underwent implant surgery and were randomly allocated into two groups: test, with two conventional implants in the anterior region and two extrashort (4-mm) implants in the posterior region; and control, with two conventional (≥ 8-mm) implants in the anterior region only. Primary stability (S1-implant placement) was assessed by insertion torque, implant stability quotient (ISQ, Osstell), and damping capacity (PTV, Periotest), while secondary stability (S221-21 days after S1; and S2clip-at prosthetic loading, ± 3 months after S1) was evaluated by ISQ and PTV. The statistical significance level was set at P < .05. Fifty conventional implants and 24 extrashort implants were placed in 25 patients. The overall survival rate was 97.3%. There was no statistically significant difference between the insertion torque of conventional and extrashort implants (P > .05). PTV values were significantly lower for conventional implants only at S2clip (P = .041). ISQ values were significantly greater for conventional implants at S1 (P = .004), whereas at S221 and S2clip, no differences were found (P = .413 and P = .490, respectively). Damping capacity showed no significant differences between S1-S2M21 and S1-S2clip. ISQ values showed a significant increase of stability between S1-S2clip, for conventional (P = .022) and extrashort (P = .005) implants, which was different from that observed between S1-S221. There was a moderate negative correlation between the PTV and ISQ variables (r = 0.5) of extrashort implants, and between the PTV and insertion torque (r = -0.3) of conventional implants. For extrashort implants, there was a null correlation between ISQ and torque (r = 0.0). There was a moderately positive correlation between ISQ and torque (r = 0.3) in the conventional implant group. The results suggest that extrashort and conventional implants present similar primary and secondary stability values and may similarly influence restorative protocols.

Immediate Loading of Two Unsplinted Implants in Edentulous Patients with Mandibular Overdentures: A 10-year Retrospective Review of Patients from a Previously Conducted 1-year Cohort Study

This 10-year retrospective study aimed to report implant bone changes in completely edentulous patients after a mandibular immediate loading protocol using two ball attachments. This study was initially designed as a prospective 1-year cohort study, then extended with a 10-year retrospective evaluation of implant bone change. In the first part of the study, 43 edentulous patients wearing satisfactory maxillary and mandibular dentures for at least 3 months were included. Two interforaminal implants (Brånemark system, Nobel Biocare) were placed symmetrically in the anterior mandible using a surgical template and a torque greater than 40 Ncm. Immediately following surgery, 2.25-mm-diameter ball abutments were screwed to the implants, and their matrices (Dalbo Plus, Cendres et Métaux) were incorporated in the denture base. In an initial 1-year study, clinical recalls were scheduled 3, 6, and 12 months after implant placement with a team of two investigators. The follow-up consisted of a clinical examination and a standardized radiographic assessment of the vertical bone change. Implant stability was then monitored. The patient satisfaction was evaluated with a questionnaire before and 3 months after loading. The second part of the study occurred 10 years after the inclusion, as patients were recalled for an implant bone change monitoring. The included patients were 28 to 80 years of age (mean: 61 ± 11.4 years). Three out of 86 implants failed during the healing phase (survival rate of 96.5% [90.1%, 99.2%]). Implant stability was maintained all along the 1-year follow-up (Δ = 73.33, 95% CI [72.39 to 74.26], P = .032). The mean radiographic bone loss was 0.27 ± 0.35 mm at 3 months after surgery, 0.47 ± 0.42 mm after 1 year, and 0.95 ± 0.98 mm after 10 years. General visual analog scale satisfaction was increased by 25 units with the treatment. No patients were lost to follow-up at 1 year, but five were lost at 10 years. This protocol of immediate loading of two unsplinted mandibular implants in overdenture patients using ball attachments is a clinically viable treatment with a high implant success rate and improved satisfaction.

Cirurgia de implantes guiada por computador: relato de caso clínico

Este estudo tem por objetivo descrever as etapas do planejamento, a funcionalidade da cirurgia de implantes guiada por computador, suas aplicações clínicas, bem como relatar um caso clínico, a cerca desse tipo de procedimento realizado em um serviço público no Brasil. Paciente F.D.C.O., gênero masculino, melanoderma, 54 anos de idade, compareceu ao Setor de Prótese Dentária do Centro de Especialidades Odontológicas Regional (CEO-R) do Crato – CE - Brasil, para reabilitação. Foi realizado confecção de próteses totais superior e inferior. Durante todo o tratamento no Setor, foi observada dificuldade de confecção da peça inferior e o paciente foi alertado que devido a reabsorção do rebordo nessa arcada, a retenção e a estabilidade provavelmente ficariam comprometidas. Diante do quadro, o mesmo foi encaminhado para uma avaliação do Setor de Cirurgia e Traumatologia Buco Maxilo Facial visando a possibilidade de enquadramento no programa de implantes dentários que se iniciava no centro de especialidades. Desde o surgimento da osseointegração os implantes dentários tornaram-se uma solução viável para o tratamento de paciente desdentados totais ou parciais. A cirurgia virtual guiada é uma opção que deve melhorar a precisão, pois proporciona um bom conhecimento anatômico da área a ser reabilitada, aprimorando então a qualidade da técnica cirúrgica, que quando associada ao desenho do implante, promove uma estabilidade primária apropriada. A cirurgia guiada de instalação dos implantes é realizada sem incisão, com as perfurações sendo feitas através do tecido mole, permitindo a precisa confecção dos alvéolos cirúrgicos artificiais e a instalação dos implantes. Quando existe a possibilidade da realização deste procedimento, o resultado é de mínimo trauma cirúrgico e excelente pós-operatório para o paciente.

Mandibular overdentures by early loaded implants in edentulous patients

Mandibular overdentures by early loaded implants in edentulous patients

Measuring the Monetary Value of Dental Implants for Denture Retention: A Willingness to Pay Approach.

Purpose:Two interforaminal dental implants in is a common treatment option for denture retention in edentulous patients. Economic methods to assess the patient’s quality of life include the willingness to pay (WTP) for implant treatment and willingness to accept (WTA) to forgo implant treatment. The purpose of this study was to assess the monetary value of implant retained complete dentures using WTP and WTA.Methods:We included a convenience sample of 16 patients from a previously published cohort study on the survival of immediately loaded implants in edentulous patients to assess WTP and WTA for this treatment option.Results:The average maximum WTP for implant treatment was 4606 (95% CI: 2991-6222) Swiss Francs. Out of the 16 patients, only 5 were willing to trade their implants for money, with a mean WTA of CHF 33'500 (range: 3000-100'000).All patients would agree to undergo the implant surgery procedure again.Conclusion:The results of the present study show that most patients are not willing to trade the increase in quality of life after implant surgery against money, suggesting that WTA exceeds by large WTP for the same health condition.

Long-term evaluation of osteotome sinus floor elevation and simultaneous placement of implants without bone grafts: 10-Year radiographic and clinical follow-up.

Insertion of an implant in the edentulous posterior maxilla is a challenging procedure because of poor bone quality and increased pneumatization of the maxillary sinus after tooth extraction. To increase the amount of bone, several surgical bone grafting techniques have been used-with considerable morbidity for patients. Osteotome sinus floor elevation (OSFE) is a less invasive technique. The clinical and radiographic outcome of 53 implants placed with this technique without bone graft has been reported previously. Here we report the clinical and radiographic findings after 10 years of implant load bearing. In a retrospective study, 34 Astra implants in 25 patients were subjected to 10-year follow-up radiologically and clinically. Each patient received 1 or 2 conical Astra implants. The level of the marginal bone and the height of the residual peri-implant alveolar bone (RPAB) for each implant were measured from digital intra-oral radiographs. Two implants in edentulous patients were lost at the 1-year follow-up, and 1 more at the 3-year examination. There was no loss between 3-year and 10-year follow-up. At 10-year follow-up 36 implants were included. Implants used in single-tooth replacements and in partially edentulous cases had a 100% survival rate. The mean marginal bone loss was 0.6 ± 0.8 mm. The bone height at the time of implant insertion ranged from 1.8 to 6.9 mm, with a mean value of 4.3 ± 1.0 mm. At 10-year follow-up the mean gain in bone at the implant sites for all implants was 2.6 ± 1.2 mm. The OSFE technique is a reliable method for rehabilitation of patients with atrophied posterior maxilla. However, the success of this method is associated with the amount of the residual bone. In the present study, this surgical approach without bone graft showed reliable long-term results with Astra implants.

Laser Biostimulation of Free Gingival Grafts Around Dental Implants

Objective : Peri-implant plastic surgery is often required in order to maintain peri-implant tissue health. Lack of keratinized tissue is especially a major problem in implants placed to edentulous patients. Long-term edentulousness causes big alterations in mandible such as keratinized tissue is reduced or lost, lips and cheeks lose support and vestibular sulcus becomes too shallow. As a consequence of keratinized tissue loss, lip covers the healing cap of the implants and free gingival autograft or vestibuloplasty is usually mandatory. The aim of this case report was to evaluate the effect of diode laser bio-stimulation on FGG procedure around dental implants in edentulous patients. Material and Methods : Material-Methods: 3 edentulous female patients (59 and 64 and 79 years old) were referred to our department in different time periods. All patients had serious alveolar bone loss because of prolonged edentulism. In clinical and radiographical examinations, it is observed that patients had lack of keratinized tissue around 6 dental implants placed in mandibular canine positions. The healing caps had been placed and there were severe soft tissue problems and disorientations and also ulcerations around healing caps. Patients were really uncomfortable and in pain because of ulcerated mucosa. Conventional vestibuloplasty and gingivectomy procedures were performed in one patient. The problem continued, lips covered healing caps again and patient was suffering from the pain again. After then in order to reduce the pain and stimulate soft tissue healing, diode laser bio-stimulation were performed in all three patients along with the FGG procedure. Totally six FGG procedures were performed in three patients. Results : Mild pain was observed in donor site and other than that there was no pain or discomfort. After 30 days, the keratinized tissues around dental implants were increased and the discomfort and pain were gone. Healing caps were placed again and the patients were treated successfully. Conclusion : FGG procedure is the gold standard for increasing the keratinized tissue around dental implants but it is a painful process. Diode laser bio-stimulation reduced the post-surgical pain and discomfort.

Functional benefits of implants placed during ablative surgery: A 5-year prospective study on the prosthodontic rehabilitation of 56 edentulous oral cancer patients.

The timing of placement as well as the functional benefit of interforaminal implants in edentulous patients treated for oral cancer is unclear. Fifty-six patients were recruited at 2 institutions. In 1 institution, interforaminal implants were placed during ablative surgery, the other institution used conventional prosthodontics with optional placement of implants postsurgery (postponed-placement). Masticatory performance, bite force, and subjective masticatory function were assessed before and 6 months, 1 year, and 5 years after surgery. Implant-retained overdentures (IODs) demonstrated the highest bite force and the least problems with solid food and food choice. Masticatory performance was equal for IODs and conventional dentures. After 5 years, IODs from patients in the during-ablative-surgery cohort tend to have higher bite force and masticatory performance than those from patients in the postponed-placement cohort. IODs produce the highest overall masticatory function. Implant placement during ablative surgery seems to be functionally beneficial. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2103-E2111, 2016.

Maxillary sinus augmentation - diagnostic and surgical technique

Placing dental implants in edentulous patients is a difficult task, as the anatomy of patients has a high variability. The expansion of the pneumatized maxillary sinus after tooth extraction is the biggest impediment of all. Because of the undersized ridge width patients need bone grafting in order to compensate the loss of their own. This procedure is performed by the oro-maxillo-facial surgeon who evaluates, advises and offers the patient the best medical guidance. A series of surgical techniques and surgical implants have been performed in the field of bone grafting, but only a few of them are now being used.

Influence of Head Orientation in Linear Measurement for Implant Planning in Cone Beam Computed Tomography.

Use of dental implants in edentulous patients has become a common treatment modality. Treatment of such implants requires radiographic evaluation, and in most cases several different imaging techniques are necessary in order to evaluate the height, width and the structure of bone at implant site. The aim of this study was to evaluate the influence of head orientation in linear measurement for implant planning in cone beam computed tomography (CBCT). In the present in vitro study, 11 human dry mandibles were used. The width and height of bone at the central, canine and molar teeth areas were measured on the left and right sides by using digital calipers (as gold standard) and on CBCT images with Reaxis option and no Reaxis. Data were analyzed with Statistical package for the social sciences (SPSS) 18, using pair t-test, Tukey test and intraclass correlation (ICC). Data were collected by evaluation of 11 skulls and 66 samples on the whole. There were no significant differences in bone width in any area in both Reaxis and no Reaxis option (p > 0.05). There were significant differences in bone height in the central (p = 0.005) and molar teeth areas (p = 0.010). The results did not show any significant differences between the observers (p = 0.329). Using the Reaxis option does not affect the measurement of bone width, while use of this option can make a significant difference for height measurements.

Soft and Hard Tissue Response to Zirconia versus Titanium One‐Piece Implants Placed in Alveolar and Palatal Sites: A Randomized Control Trial

Titanium (Ti) implants have been used in the last four decades to replace missing teeth. Alternatives to Ti such as zirconia (Zr) may offer aesthetic advantages and be more acceptable to patients and clinicians concerned about Ti allergy but must show equivalent biological acceptability to Ti. The research aimed to investigate soft and hard tissue response to Ti and Zr implants in edentulous patients. The research included 24 participants (Ti = 12, Zr = 12) restored with one-piece ball-abutment implants to support overdentures. Participants received four maxillary implants (two in the premolar alveolus, one off center in the alveolar midline, and one wide-diameter implant in the anterior median palate) and three mandibular implants (one in the midline and bilateral posterior implants). Success rates for both Ti and Zr implants were low, 67.9% for all alveolar implants and a survival rate of 50.0% for the palatal implants. Only 11 (52.4%) of 21 palatal implants survived the follow-up period. Peri-implant health was equivalent for Ti and Zr implants and showed no statistically significant changes from loading to the 1-year follow-up. Statistically significant differences were noted in radiographic bone level between Ti and Zr implants (p = .02), with Zr showing greater bone loss. Although the failure rates with the one-piece Zr implants were higher than with the Ti ones, suggesting that the former's clinical usage as in this study cannot be recommended, it should be borne in mind that the fault may also lie with the novel prosthodontic design which was used.

Osteotome Sinus Floor Elevation without Bone Grafts – A 3‐Year Retrospective Study with Astra Tech Implants

The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall. In 1994, a less-invasive technique using osteotomes was suggested by Summers. The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting. The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less. The mean height of the alveolar process in the intended implant sites was 6.3 ± 0.3 mm, and the mean elevation of the sinus floor was 4.4 ± 0.2 mm. Two implants in edentulous patients were lost at the 1-year follow-up, and one more at the 3-year examination. The remaining 50 implants inserted were in function, giving a 3-year cumulative survival rate of 94%. Implants used in single-tooth replacements and in partially edentulous cases had a 100% survival rate. The marginal bone level at the time of loading of the implants was 0.1 ± 0.04 mm below the reference point. One year later, the corresponding value was 0.5 ± 0.06 mm. The mean bone loss between the two examinations was 0.4 ± 0.05 mm. At the final examination after 3 years, the mean bone level was situated 0.6 ± 0.09 mm below the reference point, indicating a nonsignificant change between 1 year and 3 years. The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla.

Complete Fixed Prostheses Over Implants in Patients With Oral Epidermolysis Bullosa

This study was conducted to evaluate the feasibility of placing fixed prostheses over endosseous implants in edentulous patients with recessive dystrophic epidermolysis bullosa. Three cases of dental implants with fixed prostheses are presented. All 3 patients had marked oral involvement, with devastating alterations in the soft and hard tissues. The use of fixed prostheses avoids contact between the prosthesis itself and the oral mucosa, thus preventing the formation of blisters. A total of 27 implants (15 maxillary and 12 mandibular) were placed. One maxillary implant failed; the rest integrated successfully, allowing crown placement. The average follow-up after implant placement was 3 years (range, 1 to 5 years). Our findings suggest that endosseous implants are not contraindicated and can be placed successfully to improve these patients' quality of life. Implants can provide support for complete fixed prosthesis restoration in patients with epidermolysis bullosa. This procedure keeps the prosthesis from rubbing on the oral mucosa and prevents the development of ulcerations, improving mastication and esthetics.

Immediate Loaded Implants in Edentulous Patients: Clinical and Technical Aspects using Biotec Tre and Korum SP Implants

ABSTRACTToday a lot of patients ask to the clinicians how to achieve implant-supported fixed prosthesis rehabilitation in an ultra short term therapy. The answer comes from analysis of the diagnostic phase that represents the most important role in this kind of therapy, especially in the fully edentulous patients. Starting from the diagnostic wax to plan the final rehabilitation, through the right choice of implants, in this article will be represented the surgical applied principles and the prosthodontically-driven implants position. An immediate loading technique in the treatment of edentulous patients with screw-retained provisional restoration, without intrasurgical impression it will be presented, both, for the upper and lower jaws, using internal and external hex Biotec Implants (Povolaro di Dueville, Vicenza-Italy).

Implants provide better health-related quality of life than conventional treatment for edentulous patients

Question: Does use of dental implants in edentulous patients result in better quality of life compared with conventional treatment? Objective To compare the effect on health-related quality of life of two treatments for edentulism, conventional mandibular dentures and implant-supported prostheses. Design A randomised controlled trial in a hospital setting. Intervention A total of 102 people were assigned randomly into either implant or conventional treatment groups. The implant group received two implants in the lower canine region connected by a short bar. Either a conventional denture or over denture was provided in the lower jaw with conventional upper denture. Patients were analysed using the intent-to-treat principle, with patients who withdrew being allocated their pretreatment OHIP scores Outcome measures An oral health impact profile (OHIP) was conducted at the initial appointment and 2 months after the fitting of the prosthesis. Results See Table 1. Conclusions Using a validated standard assessment tool, this trial suggests that patients who had implant treatment experienced more improvements in perceived oral health than patients having conventional treatment. Acknowledgements Nobel Biocare Canada, Laboratoire Dentachrome, Dentsply Canada, the Canadian MRC, Health and Welfare Canada (NHRDP) and Fonds de Recherché en Santé du Québec.

Endosseous implants for functional masticatory rehabilitation in the extremely atrophied edentulous maxilla

The aim of this retrospective study was to evaluate the long-term survival rate of dental implants in edentulous patients suffering from severe atrophy of the alveolar ridges in the upper jaw. In total, 964 implants were inserted in 140 patients. A total of 481 implants were combined with an osteoplastic augmentation of the maxilla, and 483 implants were inserted directly in the atrophic bone. The success rate was determined using survival analysis, log rank tests and a Cox regression analysis. The overall survival rate for all implants was 42.2% during an observation period of 11 years. Between implants combined with an osteoplasty and implants inserted in local bone tissue there were no significant differences in the survival rate. The survival rate of implants combined with an osteoplasty was significantly reduced in women and in the case of repeated insertion or augmentation. Interestingly, a few of the patients treated with an osteoplasty demonstrated high numbers of individual implant failures. Those patients were postmenopausal women exclusively. Among them there is probably a certain group with a very high risk of implant failures. This study shows that oral rehabilitation with osteointegrated implants in patients with severely atrophic alveolar ridges in the upper jaw is still problematic.

Periodontal bacteria colonizing oral mucous membranes in edentulous patients wearing dental implants.

The purpose of this study was to investigate the prevalence of the microbiota on the oral mucosal surfaces and in the peri-implant pocket in edentulous subjects with a past history of periodontitis. Twenty edentulous subjects wearing dental implants for at least one year and with a history of periodontitis participated in this study. Clinical parameters were assessed (plaque, redness, swelling, peri-implant probing depth [PIPD], and bleeding on probing) and microbiological samples were taken (oral mucosal surfaces, saliva, plaque, and peri-implant pocket). Based on the clinical results, the group as a whole showed healthy peri-implant tissues. A mean PIPD of 3.6 mm was found. A statistically significant correlation was found between the PIPD and bleeding upon probing, plaque scores, redness, and swelling. Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were not detected. The subjects harboring Prevotella intermedia showed presence of PIPD of > or = 5 mm. All subjects harbored Peptostreptococcus spp., Fusobacterium spp., and other Prevotella species. Actinomyces odontolyticus, Bacteroides forsythus, Campylobacter rectus, Pseudomonas spp., and enterobacteria were detected less frequently. Three subjects showed signs of overt soft tissue inflammation. They harbored higher proportions of Peptostreptococcus spp. than the other subjects. The results corroborate the suggestion that the primary source of colonization for dental implants in edentulous patients are the oral mucous membranes. The results indicate that the microbiota of subjects wearing dental implants with a past history of periodontitis are composed of bacteria associated with a healthy periodontium or gingivitis. It is suggested that elimination of the subgingival environment by extraction of all natural teeth probably initiates the disappearance of the two periodontal bacteria A. actinomycetemcomitans and P. gingivalis.

Colonization of osseointegrated titanium implants in edentulous patients. Early results.

The purpose of this investigation was to study the colonization of newly set implants in edentates and to monitor the development of the predominant subgingival microbiota during the first 6 months of wearing the implants in vivo. Microbial samples of the receiving sites were taken one day prior to the insertion with sterile cotton pellets. After implantation, one site per implant was sampled with sterile paperpoints once every week for 2 months, and thereafter in monthly intervals up to 180 days. A total of 114 samples of 9 sites from 5 patients were evaluated using the darkfield microscope and cultured anaerobically on non‐selective and selective media. Representative colonies were identified by atmospheric growth capabilities, Gram‐staining characteristics and biochemical tests. Small amounts of bacteria were collected from the preoperative swabs. On an average 86% of the microorganisms were identified morphologically as coccoid cells and over 80% of the cultivated bacteria were Gram‐positive facultative cocci. After implantation, no significant changes in these proportions could be observed in all but one site. In this particular site a steady decrease of coccoid cells and a simultaneous increase of rods was observed after 21 days. Actinomyces odontolyticus was first detected at Day 21 and Fusobacterium spp. were first detected at Day 42; at Day 120 small spirochetes were found for the first time, pus formation was noted clinically and a pocket probing depth of 6 mm was recorded. None of the other sites showed probing depths of over 3 mm or pus formation. In these clinically successful sites spirochetes were never seen. Fusobacteria could only be detected in 13 of 104 samples. Black‐pigmenting Bacteroides were found infrequently and no trend of increase was apparent in any site over the 180 days of monitoring.