Immediate transition to an implant-supported dentition

Immediate implant placement and loading is becoming increasingly acceptable. However, to be successful, very careful case selection is required, and even if this is achieved, the clinical situation that develops as soon as the natural teeth are removed may prove much less adequate for implant stability, positioning, and survival than anticipated. It makes sense to "over engineer" a case and to place more implants rather than fewer to ensure adequate support during the critical early phase of therapy, particularly when the implants are loaded at the time of placement. It also should be appreciated that immediate transition induces gross changes that can make it difficult to predict the final esthetic outcome.

Implant-retained overdenture following hemiglossectomy: a 10-year clinical case report

A clinical evaluation of an implant-supported overdenture placed in the edentulous mandible after hemiglossectomy is described. The deltopectoral flap covering the mandibular ridge was replaced with a free mucosal graft. Four Brånemark system implants were inserted into the anterior part of the mandible, but one of the four fixtures did not show osseointegration. The superstructure was designed as a spaced round bar-attachment supported by three implants so as to retain the complete overdenture. In addition to the metal clip, a silicone-based soft denture liner material was applied in the female portion of the attachment so as to prevent the attachment from making a clattering noise upon mastication. Although the overdenture required adjustment at regular intervals, the treatment was successful both aesthetically and functionally for up to at least 10 years.

[Clinical study of immediate placement and early loading of dental implants]

OBJECTIVE

To evaluate the clinical results of immediate placement and early loading of dental implants.

METHODS

Sixty-four dental implants were inserted into the edentulous section of 37 patients immediately after the teeth were extracted. 36 implants were inserted by one-stage operation procedure, of which 17 implants were loaded immediately in 3 edentulous jaws by temporary mandibular overdenture. Fixed crown restoration were completed on 14 implants in 1 - 2 months and on 22 implants in 3 - 4 months. The two-stage operation for another 28 implants were performed after 3 - 6 months and then were restored by routine methods.

RESULTS

All implants were inserted successfully and stable. There was no peri-implantitis and X-ray films indicated that no remarkable bone resorption occurred. There were no significant differences in the peri-implant depths of gingival pocket between early loading implants and routine restoration.

CONCLUSIONS

Dental immediate implant and early loading after implantation can shorten the treatment period of implant-supported prosthesis. The short-term clinical performance was not different from the routine method.

Tissue alterations at implant-supported single-tooth replacements: a 1-year prospective clinical study

OBJECTIVES

The aim of this prospective study was to evaluate dimensional alterations of the peri-implant tissues at single-tooth restorations from the time of implant placement to 1-year post-loading.

MATERIAL AND METHODS

Eleven patients, aged 18-36 years, subjected to single-tooth replacements with implant-supported restorations (Brånemark implant system) in the maxillary anterior region were included in the analysis. The implant installation was performed as a two-stage procedure with a 6-month healing interval. Bone dimensions were determined by direct assessments immediately following implant placement and at abutment connection. The prosthetic restoration was placed approximately 1 month after abutment surgery. Radiographic and clinical examinations were performed at crown placement and at 1-year post-loading. Assessments of the soft tissues at the implant site and at the neighboring teeth were performed before and during implant placement, before abutment connection, after crown placement and at the 1-year follow-up examination. Mean values and standard deviations were calculated for each variable and interval, with the subject as the statistical unit.

RESULTS

At the time of abutment connection, a mean loss of bone height at the facial and lingual aspect of the implant amounting to 0.7-1.3 mm (P < 0.05) was recorded, whereas no significant change was noted at proximal sites. A mean reduction of 0.4 mm of the labial bone thickness was observed between implant placement and the second-stage surgery. The radiographic bone-to-implant level showed a mean loss of 0.9 mm between abutment connection and crown placement (P<0.05) and a further 0.7 mm loss at 1 year (P < 0.05). The thickness of the labial mucosa was increased at crown placement followed by a slight remission at 1 year. During the corresponding interval, a mean apical displacement of the labial soft tissue margin of 0.6 mm had taken place (P < 0.05). A papilla fill of > or = 50% was observed at a frequency of 32% at crown placement and 86% at 1 year.

CONCLUSIONS

The results demonstrated that following implant surgery remodeling takes place, which is manifested in diminished bone dimensions, both horizontally and vertically, at the facial aspect of the implant. The observed soft tissue alterations after the crown placement may affect the esthetic appeal of the restorative therapy.

Reconstructive materials and bone tissue engineering in implant dentistry

Periodontal function for natural teeth and dental implants depends strongly on the mechanical integrity of the bone in the maxilla and mandible. Ongoing healthy bone remodeling around a natural tooth or implant is critical for longevity. Chemical factors that influence bone remodeling have been explored with the goal of enhancing the growth and maintenance of good quality bone. Less, but increasing, effort has been directed at understanding mechanical signals and factors, including those affected by implant/prosthesis materials that transmit loads directly to the surrounding bone. This article reviews research on the effects of synthetic materials and resulting mechanical stimuli on bone tissue engineering in dentistry.

Clinical Outcome of Implants Placed Immediately After Implant Removal

BACKGROUND

The purpose of this study was to evaluate the clinical success of implants placed immediately after the explantation of failed implants due to fracture at 12 months.

METHODS

Nine immediate implants were placed in nine patients following explantation of nine fractured implants. Five experimental implants did not require any regenerative procedures; the remaining four immediate implants were grafted with deproteinized porcine bone particles and covered with bioabsorbable membranes. All implants were restored with fixed prostheses. The follow-up period was 12 months.

RESULTS

No residual bone defects were observed or probed around any implant at the second-stage surgery, and all implants were asymptomatic and stable. All the implants were successful after prosthetic rehabilitation showing no mobility, pain, suppuration, or absence of peri-implant radiolucency. The radiographic measurements showed no significant bone loss pattern at the 12-month follow-up visit.

CONCLUSION

The findings of this study suggested that implants placed immediately after implant explantation due to biomechanical fracture could be performed with results that are similar to results obtained with implants placed immediately after tooth extraction.

Use of Mini Implants for Replacement and Immediate Loading of 2 Single-tooth Restorations: A Clinical Case Report

Numerous long-term studies have shown that treatment with dental implants can provide edentulous patients with a more stable alternative to complete dentures and partially edentulous patients with a more conservative form of tooth replacement than conventional fixed partial dentures. Until recently, commercially available dental implants have been limited to diameters ranging from 3.0 mm to 7.0 mm. Although this range of diameters has been able to address most clinical needs, partially edentulous patients who could not accommodate a 3.0-mm-diameter implant without damaging adjacent dental structures were excluded from implant therapy. This article reports on the surgical treatment and immediate restoration of a patient who received mini implants that were 2.4 mm in diameter.

Sinus graft with biogran, autogenous bone, and PRP: a report of three cases with histology and micro-CT

Three sinuses were grafted with a bioactive glass bone substitute (Biogran) mixed with autogenous bone retrieved from intraoral donor sites. In two of the three sinuses a platelet-rich plasma (PRP) gel was added to the graft. Bone biopsies retrieved after 5, 6, and 15 months were analyzed. Micro-computerized tomography (micro-CT) values of total bone volume/total volume (TBV/TV) were very reliable compared to histomorphometry. Biogran mixed with autogenous bone and PRP seems to have a positive effect in sinus grafting, with TBV/TV values ranging between 40% and 68%. Micro-CT results have never been compared with histomorphometry for the evaluation of grafted biomaterials. Micro-CT evaluation of some morphometric parameters was difficult, because the radiodensities of Biogran and a certain grade of bone mineralization were similar.

Implant Reconstruction of the Bone- Grafted Maxilla: Review of the Literature and Presentation of 8 Cases

PURPOSE

This study prospectively investigates the long-term success of iliac crest bone grafting and the secondary placement of osseointegrated implants in reconstructing maxillae with severely reduced bone mass.

MATERIALS AND METHODS

Eight consecutive patients (7 women, 1 man), aged 18 to 69 (mean, 49.6), were treated by augmentation of their maxillae with corticocancellous autogenous iliac bone blocks. Forty-one Branemark implants of 7 to 15 mm in length and 3.75 mm in diameter were placed after a minimum delay of 6 months. Bone healing, maintenance of bone height, and implant stability were measured by clinical examination and radiographic control.

RESULTS

One patient was lost to follow-up at 24 months after delivery of the prosthesis and one was lost at 75 months. The average duration of follow-up after loading of the implants was 90.5 months, and the longest was 154 months. Thirty-four of 41 (83%) of the implants survived to the end of the observation period. Four of 6 implants that failed were 7 mm in length and the other 2 were 10 mm in length. One 10-mm implant was "slept" because of poor positioning. All prostheses survived. There was one significant gingival infection that resulted in loss of 1.5 mm of bone after which the implant remained stable. None of the other implants were associated with crestal bone loss of more than 0.5 mm for the duration of this study.

CONCLUSIONS

Delayed placement of osseointegrated implants in maxillae augmented by iliac bone grafts is predictable and successful in the long term.

Management strategies of the unsalvageable tooth

A tooth is deemed unsalvageable when it can no longer be preserved for use of function or aesthetic purposes. If proper treatment planning is done, tooth extraction can be performed with adjunctive procedures, to provide a more predictable restorative outcome for the patient. This review paper summarizes the possible treatment strategies available for the management of a tooth with a poor prognosis, so as to manage the patient better before the restorative treatment phase commences.

CLINICAL RELEVANCE

The management of an unsalvageable tooth using interdisciplinary approaches offers the clinician strategies for providing a more favourable restorative outcome.

Cone Beam Computerized Tomography-based Dental Imaging for Implant Planning and Surgical Guidance, Part 1: Single Implant in the Mandibular Molar Region

Computerized tomography (CT)-based dental imaging for implant planning and surgical guidance carries both restorative information for implant positioning, as far as trajectory and distribution, and radiographic information, as far as depth and proximity to critical anatomic landmarks such as the mandibular canal, maxillary sinus, and adjacent teeth. This case report describes a systematic approach to the planning and surgical placement of a single implant-supported crown, utilizing CT-based dental imaging for implant planning and surgical guidance. The simple steps result in the accurate transfer of critical radiographic information to the surgical site.

Non-grafted sinus implants in periodontally compromised patients: a time-to-event analysis

This study reports the results of implant therapy involving a sinus membrane lift and of conventional implant therapy in 68 periodontally compromised patients treated between June 1990 and June 2002. Patients had at least two implants inserted, one of which was placed in the maxillary sinus region following fenestration of the lateral sinus wall and lifting of the sinus membrane. Two implant systems were used: a two-stage system (Astra) and a one-stage system (ITI). Annual follow-up visits included recording of plaque, probing pocket depth and measurement of the radiographic distance in millimeter from the implant shoulder to the alveolar crest. Survival analysis showed that the proportion of implants that had not been explanted after 5 years ranged between 88.7% for ITI sinus implants and 97% for ASTRA conventional implants. After 10 years, the proportion of implants remaining in situ ranged between 59% for ITI conventional implants and 97% for ASTRA conventional implants. Cox regression analyses showed that the factors influential for implant explantation were implant type (HR(ITI) = 2.8), implant length (HR(< or = 10 mm) = 3.1), patient being a smoker (HR(smoking) = 2.2) and patient having at least 20 natural teeth (HR(> or = 20 teeth) = 3.8). Our results demonstrate that sinus implants may be inserted with the same success as conventional implants in periodontally compromised patients.

Early osteotomy with delayed implant placement: a step further for immediate loading

The commonly used implantation technique involves a 2-stage surgical protocol for load-free and submerged healing to ensure predictable osseointegration. This article presents a new approach that benefits from previous bone and soft tissue protocols. It combines new surgical and insertion techniques to perform immediate loading with delayed implant placement, avoiding the problems of discomfort, inconvenience, and anxiety associated with healing periods. It maintains a similar success rate to the present common technique. After osteotomy, bone healing passes through 3 stages (i.e., inflammation, fibrous tissue, and maturation). In the new approach, implant insertion is performed 2 weeks after drilling (i.e., during the fibrous phase). The insertion timing is so selected because collagen formation and revascularization represent an acceptable implant bed configuration. Flap surgery offers the optimal osteotomy approach, but esthetic outcomes are definitely compromised. Accordingly, adopting the punch technique alleviates several postoperative problems, such as pain, tenderness, and swelling. Moreover, the punch technique avoids the sutures needed to adjust the gingiva around the abutment. It provides both cosmetic and functional properties.

Computer-guided flapless transmucosal implant placement in the mandible: a new combination of two innovative techniques

OBJECTIVE

To assess whether computer-guided flapless transmucosal implant bed preparation without mucosal punching allows placement of dental implants in edentulous mandibles.

STUDY DESIGN

Twenty patients with fully edentulous mandibles (11 male; 9 female) were included in the study. Each patient was scheduled to receive 4 screw-shaped Ankylos (Dentsply Friadent, Mannheim, Germany) implants in the interforaminal region. The StealthStation Treon navigation system (Medtronic, Minnesota, MN) was used for computer-guided drilling. Using conventional implant drills the mucosa was penetrated without flap elevation or mucosal punching. The study protocol did not allow direct visualization of the bone surface during surgery.

RESULTS

For 78 implants (97.5%) the preoperative plan could be transfered to the patient by intraoperative navigation with a mean deviation of 0.9 mm (Implant tip 0.8 +/- 0.6 mm; coronal implant end 1.1 +/- 0.7 mm) as measured by comparing pre- and postoperative computerized tomography images. Two implants (2.5 %) were not primarily stable and failed to osseointegrate.

CONCLUSIONS

Computer-guided transmucosal interforaminal implant placement without mucosal punching is a precise and predictable procedure. It is, however, not yet suitable for all bone morphologies. Future developments may include miniaturization of hardware and simplification of the drilling procedure.

Immediate placement of implants in periapical infected sites: a prospective randomized study in 50 patients

OBJECTIVE

To determine clinical success when implants are placed in chronic periapical infected sites.

STUDY DESIGN

Fifty patients (25 females, 25 males, mean age 39.7 +/- 14.5 years) were included in this prospective controlled study. After randomization, 25 Frialit-2 Synchro implants were immediately placed (IP) after extraction, and 25 Frialit-2 Synchro implants were placed after a 3-month healing period (DP). Thirty-two implants were placed in the anterior maxilla and 18 implants were placed in the premolar region. Implant survival, mean Implant Stability Quotient (ISQ) values, gingival aesthetics, radiographic bone loss, and microbiologic characteristics of periapical lesions were evaluated for both groups.

RESULTS

Overall, 2 implants belonging to the IP group were lost, resulting in a survival rate of 92% for IP implants versus 100% for DP implants. Mean ISQ, gingival aesthetics and radiographic bone resorption, and periapical cultures were not significantly different with the IP and DP implants.

CONCLUSIONS

Immediate implant placement in chronic periapical lesions may be indicated.

The evaluation of vertical heights of maxillary and mandibular bones and the location of anatomic landmarks in panoramic radiographs of edentulous patients for implant dentistry

The purpose of this study was to determine variations in the vertical height measurements in the edentulous maxilla and mandible, and to assess positions of the maxillary sinus, mandibular foramen, and the mandibular canal, which are important for implant length selection and planning using panoramic radiographs. The study sample included 346 edentulous alveolar ridges of 90 men and 83 women. Sixty-three dentate patients' panoramic radiographs were used for location of the first premolar and molar area. Panoramic radiographs were made with a Siemens Orthophos panoramic machine which had been standardized previously. All radiographs were made using a standardized manner by the same technician. Fourteen sites were measured on every panoramic radiograph whenever possible, eight sites in the maxilla and six sites in the mandible. Correlation analyses were performed between age groups and all measurements to determine if age is significant as a covariate. In order to examine the effect of gender the statistical analysis of differences between men and women was performed with Student t-test. The 5% significance level was used for statistical significancy. The height of the maxilla and the mandible in the anterior, first premolar, and first molar regions were significantly greater in men than in women. A majority of the most inferior border of the maxillary sinuses was located anterior to the first molar area (premolar regions) both in men (48.9%) and women (55.4%). Although, there was no statistically significant difference between edentulous men and women for the vertical distances from the mental foramen to the alveolar crest, and horizontal distances from mental foramen to midline, there were statistically significant differences between edentulous men and edentulous women for the vertical distances from the upper border of the mandibular canal to the alveolar crest in the first molar area. Mental foramens were located at the crest of the ridge in 7.2% of the edentulous women, and 6.7% of the edentulous men. The results of this study may guide clinicians to make primer decision of implant insertion area for implant supported prosthesis in edentulous patients.

Effect of flapless surgery on pain experienced in implant placement using an image-guided system

PURPOSE

The aim of this study was to compare the pain experienced after implant placement with 2 different surgical procedures: a flapless surgical procedure using an image-guided system based on a template and an open-flap procedure.

MATERIALS AND METHODS

The study population consisted of 60 patients who were referred for implant placement. One group consisted of 30 patients who were referred for the placement of 80 implants and treated with a flapless procedure. The other group consisted of 30 patients who were referred for the placement of 72 implants with a conventional procedure. Patients were selected randomly. They were requested to fill out a questionnaire using a visual analog scale (VAS) to assess the pain experienced and to indicate the number of analgesic tablets taken every postoperative day from the day of the surgery (DO) to 6 days after surgery (D6).

RESULTS

The results showed a significant difference in pain measurements, with higher scores on the VAS with open-flap surgery (P < .01). Pain decreased faster with the flapless procedure (P = .05). The number of patients who felt no pain (VAS = 0) was higher with the flapless procedure (43% at DO versus 20%). With the flapless procedure, patients took fewer pain tablets (P = .03) and the number of tablets taken decreased faster (P = .04).

DISCUSSION

Minimally invasive procedures may be requested by patients to reduce their anxiety and the pain experienced and thus increase the treatment acceptance rate.

CONCLUSION

With the flapless procedure, patients experienced pain less intensely and for shorter periods of time.

Alveolar Segmental “Sandwich” Osteotomies for Posterior Edentulous Mandibular Sites for Dental Implants

PURPOSE

The purpose of this retrospective study was to evaluate crestal stability of alveolar augmentation using an interpositional bone graft for dental implant restorations.

PATIENTS AND METHODS

Eight patients with 10 graft sites were followed from 1 to 4 years with panographic evaluation to determine if dimension changes of the alveolar graft sites had occurred.

RESULTS

Ten graft sites showed stability and maintenance of alveolar form and osseointegration of restored dental implants. Very little loss of crestal height was observed; 20 of 22 implants placed remained stable at follow-up.

CONCLUSION

The interpositional alveolar bone graft appears to be a viable alternative to block grafting or guided bone regeneration.

Three-year data from a randomizd, controlled study of early loading of single-stage dental implants supporting maxillary full-arch prostheses

PURPOSE

The aim of this 3-year randomized controlled trial (RCT) was to compare biologic and technical treatment outcomes and patient satisfaction after early (< or = 14 days postimplantation) loaded implants with those of implants loaded after a healing period of 3 to 4 months in the edentulous maxilla.

MATERIALS AND METHODS

Twenty-four patients with completely edentulous maxillae were randomized into a test group (n = 16) and a control group (n = 8). All patients received 5 or 6 solid screw-type titanium implants with sandblasted, large-grit, acid-etched (SLA) surfaces. In total, 142 implants were placed and 139 implants were loaded with full-arch prostheses. Clinical assessments were obtained at loading and after 3, 6, 12, 24, and 36 months. Radiographs of implants and existing teeth were taken at loading; after 6, 12, 24, and 36 months; and at 12, 24, and 36 months, respectively.

RESULTS

The cumulative implant success rate 3 years after loading was 100%. At the 3-year examination the mean (P < or = .005), distal (P < or = .005), and mesial (P > .05) crestal bone levels were better in the test group. No significant differences between the test and control groups were noted for any other outcome measure. The most common adverse event in both groups was tooth-crown fracture.

DISCUSSION

A review of the literature, both printed and electronic, revealed no study fulfilling the criteria of an RCT dealing with the early loading of maxillary full-arch prostheses. This study fulfills those criteria.

CONCLUSION

In this study population it has been concluded that the early (approximately 2 weeks) loading protocol is a viable alternative to the standard (3 to 4 months) protocol in the rehabilitation of a completely edentulous maxilla with a complete implant-supported fixed prosthesis.

Using a fixed provisional prosthesis during post-extraction healing and implant placement

Most dental patients insist on the use of provisional prostheses throughout healing and osseointegration when replacing extracted teeth with implants in esthetically sensitive areas. Removable appliances of some kind are normally used for this purpose, but patients often consider them to be too cumbersome. This can lead to decreased case acceptance and compliance with the use of the provisional restoration, which can compromise the final result of treatment. Custom fixed solutions to this problem exist, but they tend to be more complicated, less practical, and more expensive than other options now available. The Monodont bridge, a new system of prefabricated components for the creation of provisional fixed partial dentures, can be more esthetic, more retentive, more functional, more cost-effective, and more universally applicable than any other available techniques. This can raise patient tolerance of provisional prostheses and thus increase case acceptance, while fostering a more predictable esthetic result with regard to soft tissue contours and emergence profile.

Immediate Loading of Implant Overdentures Using Modified Loading Protocol

To our knowledge, this study shows the first longitudinal results (range 12-30 months) of immediate loading of implant-support overdenture with ball attachment connection placed in the anterior mandible. Immediately after surgery, the overdenture was connected to the implants with 2-ball attachments. The housings were filled with Impregum (3M Espe AG; Seefeld, Germany) impression material to provide retention as well as reduce forces in the initial phase of loading. Of the 28 implants placed, only 1 failed; the 1 failed implant for total implants placed represents a success rate of 96.4%. The minimal bone loss (1 mm) in 2 sites represents a success rate of 92.8%.

The ‘mini'-implant has arrived

There is no question that dental implants have been the most influential change in dentistry during the last half-century. In general, they are well-proven and highly useful. However, the diameter of standard implants (approximately 3.75 mm), along with the frequent need to graft bone to allow for their placement, have limited their use for those who most need implants. The introduction, approval and continuing observation of success of smaller-diameter mini-implants have stimulated use of implants in situations in which standard-sized implants could not have been used without grafting. The result has been more patients who have been served successfully at reduced cost with minimized pain and trauma--patients who could not have been treated with implants otherwise. Continuing research is needed for further verification of the acceptability of mini-implants.