Vertical crestal bone changes around implants placed into fresh extraction sockets

BACKGROUND: The aim of this study was to analyze bone healing and vertical bone remodeling for implants placed immediately after tooth removal without guided bone regeneration techniques. METHODS: Twenty patients received 20 implants immediately after the removal of 20 teeth. All implants were placed within the undamaged alveoli confines, and the cervical portion of each implant was positioned at coronal bone level. The distance from implant shoulder and bone crest was measured for each implant at four sites (mesial, buccal, distal, and palatal/lingual). No membranes or filling materials were used. Primary flap closure was performed in all clinical cases. RESULTS: All peri-implant bone defects had healed completely 6 months after implant placement. The pattern of bone healing around the neck of the implants showed an absence of peri-implant defects. The vertical distance between the implant shoulder and bone crest ranged from 0 to 2 mm. CONCLUSIONS: The bone remodeling of implants placed in fresh extraction sockets showed a healing pattern with new bone apposition around the implant's neck and horizontal and vertical bone reabsorption. The vertical bone reabsorption, which has been observed at buccal sites, was not associated with any negative esthetic implications.     

Bone remodelling after regenerative procedures around implants placed in fresh extraction sockets: an experimental study in Beagle dogs

Introduction: After a tooth extraction, the height of the buccal wall tends to decrease. The literature indicates that regenerative techniques (guided bone regenerative [GBR] techniques) have succeeded in improving the bone levels. Therefore, this experiment set out to compare the physiological bone remodelling in Beagle dog models after implant placement in a fresh extraction socket, with and without the application of regenerative procedure. Materials and methods: Five dogs were used in this study. Test and control sites were randomly selected. The experimental teeth (fourth pre‐molar and first molar) were hemi‐sected removing the distal roots and placing implants. Porcine bone was placed to fill the gap around the implant on the test sites and a reabsorbable membrane was used to cover the area. The dogs were put down at different times (2 weeks, 1 month and 3 months). The measurements were taken immediately and at 2, 4, 12 weeks after implant placement. Student's test for paired data was used to compare the means of the clinical measurements. Results: At 2 weeks: On the control sites, few signs of resorption were detected at the first molar only, while at the test sites bone levels were placed at the implant shoulder or above. At 4 weeks: On the control site, slight bone remodelling was observed, while on the test site minor signs of resorption or an increase of bone levels were detected. At 12 weeks: The alveolar crest on the control sites showed various degrees of remodelling. On the test sites stable bone levels or an increase of bone crest was observed. Conclusion: With the limits of this study, the findings showed that GBR techniques were able to limit resorption of the alveolar crest after tooth extraction. A pattern of bone remodelling after tooth extraction and implant placement was observed in the control sites (no GBR) as well as in test sites (GBR), and although the exact cause of this is unclear, surgical trauma could play a role. Further studies are necessary to confirm these results and to clarify the precise causes of bone remodelling in fresh extraction sockets. To cite this article:
Barone A, Ricci M, Calvo‐Guirado JL, Covani U. Bone remodelling after regenerative procedures around implants placed in fresh extraction sockets: an experimental study in the Beagle dogs.
Clin. Oral Impl. Res. 22 , 2011; 1131–1137
doi: 10.1111/j.1600‐0501.2010.02084.x     

Bucco-lingual bone remodeling around implants placed into immediate extraction sockets: a case series

BACKGROUND: Implants placed immediately after tooth extraction have shown high percentages of clinical success. Few studies in the scientific literature have observed the horizontal bone remodeling in the buccal-lingual direction after immediate placement of implants. The aim of this study was to analyze bone healing and coronal bone remodeling around 15 implants placed immediately after tooth removal without the use of guided bone regeneration (GBR) techniques. METHODS: Ten patients received a total of 15 implants placed immediately after removal of 15 single-rooted teeth. All implants were placed within the alveolar confines, limiting, in most cases, small peri-implant bone defects. After implant placement, the distance from the buccal to lingual bone plate was measured. No membranes or filling materials were used. Primary flap closure was performed in all cases. RESULTS: At second-stage surgery, all peri-implant defects were completely filled and the distance from buccal to lingual bone was measured again. The pattern of bone healing around the neck of immediate implants showed an absence of peri-implant defects and a narrowing of bone crest width in a buccal-lingual direction. The mean distance between buccal bone and lingual bone at the time of implant placement was 10.5 mm (+/- 1.52) and, at second-stage surgery, 6.8 mm (+/- 1.33). CONCLUSIONS: The coronal bone remodeling around immediate implants showed a healing pattern with new bone apposition around the neck of the implants and, at the same time, bone resorption with horizontal width reduction of the bone ridge. The small peri-implant bone defects were completely healed without the use of GBR procedures. An absence of complications during the healing period was also observed, probably due to the absence of barrier membranes and grafting materials.     

Bone dimensional variations at implants placed in fresh extraction sockets: a multilevel multivariate analysis

Aim: To use multilevel, multivariate models to analyze factors that may affect bone alterations during healing after an implant immediately placed into an extraction socket. Material and methods: Data included in the current analysis were obtained from a clinical trial in which a series of measurements were performed to characterize the extraction site immediately after implant installation and at re‐entry 4 months later. A regression multilevel, multivariate model was built to analyze factors affecting the following variables: (i) the distance between the implant surface and the outer bony crest (S‐OC), (ii) the horizontal residual gap (S‐IC), (iii) the vertical residual gap (R‐D) and (iv) the vertical position of the bone crest opposite the implant (R‐C). Results: It was demonstrated that (i) the S‐OC change was significantly affected by the thickness of the bone crest; (ii) the size of the residual gap was dependent of the size of the initial gap and the thickness of the bone crest; and (iii) the reduction of the buccal vertical gap was dependent on the age of the subject. Moreover, the position of the implant opposite the alveolar crest of the buccal ridge and its bucco‐lingual implant position influenced the amount of buccal crest resorption. Conclusions: Clinicians must consider the thickness of the buccal bony wall in the extraction site and the vertical as well as the horizontal positioning of the implant in the socket, because these factors will influence hard tissue changes during healing. To cite this article:
Tomasi C, Sanz M, Cecchinato D, Pjetursson B, Ferrus J, Lang NP, Lindhe J. Bone dimensional variations at implants placed in fresh extraction sockets: a multilevel multivariate analysis.
Clin. Oral Impl. Res. 21 , 2010; 30–36.     

Immediate occlusal loading of implants placed in fresh sockets after tooth extraction

PURPOSE: The aim of this study was to evaluate the clinical and radiographic outcome of dental implants immediately placed and loaded into fresh extraction sockets after 18 months. MATERIALS AND METHODS: Twenty-seven patients, 15 women and 12 men, received a total of 160 implants; 150 were placed immediately after extraction. The sockets in the study had fully preserved walls, and 10 were placed in healed sites. Immediately after surgical procedure, all patients received the temporary prosthetic reconstruction in occlusion. Five months postsurgery, definitive metal-ceramic restorations were cemented on abutments. Follow-up visits were performed for the assessment of clinical parameters. Intraoral digital radiographic examinations were performed 3 and 18 months after implant placement. RESULTS: Minor swelling of the gingival mucosa was observed, but no mucositis or flap dehiscence with suppuration were found. Mean marginal bone loss 1 year 18 months after immediate loading was 0.65 +/- 0.58 mm to the mesial side and 0.84 +/- 0.69 mm to the distal side in the maxilla and 1.13 +/- 0.51 mm mesially and 1.24 +/- 0.60 mm distally in the mandible. There was no difference between splinted and nonsplinted implants with respect to marginal bone loss. Discussion and CONCLUSION: Within the limits of this clinical study, the results indicate that immediate loading of implants placed in immediate extraction sites can be carried out successfully. (Case Series)     

Bone tissue formation adjacent to implants placed in fresh extraction sockets: an experimental study in dogs

OBJECTIVE: To study the healing of marginal defects that occurred at implants placed in a healed ridge or in fresh extraction sockets. MATERIAL AND METHODS: Six dogs were used. The right side of the mandible was used in the first part of the study. The first, second premolars and first molars were extracted. After 3 months of healing the bone was prepared for implant installation in these premolar and molar sites. The marginal 5 mm of each recipient site was widened with a conical drill. Following implant installation a gap of varying dimension occurred around the titanium rod (artificial defect (A) sites). At this interval the third and fourth premolars were extracted and implants were installed in the distal socket of the two teeth (natural defect (N) sites). The flaps were sutured to allow non-submerged healing. After 2 months, the procedures were repeated in the left side. Two months later the animals were euthanized, and biopsies were obtained and prepared for histological examination. RESULTS: The length of the zone of de novo'bone-to-implant contact' in the defect region was longer at the A sites than at the N sites both at the 2- and the 4-month interval. Further, while after 4 months of healing the marginal bone crest at the A sites was located close to the abutment/fixture junction, at the N sites a marked reduction of the height of the bone crest was documented. Hence, most A site defects became completely resolved whereas healing of the N site defects was incomplete. CONCLUSION: The process of bone modeling and remodeling at an implant placed in a fresh extraction socket differs from the resolution of marginal defects that may occur following implant installation in a healed ridge.     

Survival of immediately provisionalized dental implants placed immediately into fresh extraction sockets

BACKGROUND: The aim of this study was to evaluate the survival rate of immediately provisionalized dental implants immediately placed into fresh extraction sockets. METHODS: The study consisted of 87 consecutive patients, ranging in age from 21 to 76 years (average: 53.30 +/- 13.34 years), who received 210 immediately provisionalized, immediately placed dental implants between the years 2000 and 2005. Data were recorded regarding the survival rate of these implants and the incidence of complications. RESULTS: Follow-up ranged from 6 to 52 months (mean: 15.60 +/- 12.60 months). Smoking, past and present, was reported by 28.7% and 20.7% of patients, respectively. The maxillary incisors were replaced most frequently, followed by the mandibular lateral incisors. Most of the implants were >13 mm in length and > or = 3.75 mm in diameter. There were 47 (22.4%) single restored implants and 163 (77.6%) splinted implants. Overall, the implant survival rate was 97.6% (five implants failed). Complications, such as swelling, inflammation, and pain, were observed in 24 (11.4%) of the implants. No relation was found between complications and failure. The present study failed to reveal a relationship between implant survival rate and smoking, implant dimensions, and area of implantation. CONCLUSION: Immediately provisionalized immediate implants can serve as a predictable procedure with high survival rates.     

Clinical outcome of submerged vs. non-submerged implants placed in fresh extraction sockets

Aim: The aim of this study was to compare the clinical outcome of submerged vs. non-submerged tapered implants placed into fresh extraction sockets.
Materials and methods: A prospective, controlled, multicenter, randomized, clinical trial has been performed in two centers in Rome and Torino (Italy). Thirty healthy patients were recruited according to the following inclusion criteria: need for an immediate post extraction implant, ages between 18 and 70, horizontal defect depth <2 mm, smokers <10 cigarettes/day and absence of any circumstance or condition that could represent contraindications to implant surgery. The patients were randomly allocated to submerged or non-submerged treatment groups immediately after flap elevation and tooth extraction. Submerged implants were exposed 8 weeks after the first surgery; all implants were loaded with provisional restorations 12 weeks after the first surgery and with definitive restoration 12 weeks thereafter. Clinical and radiographic parameters were evaluated at baseline, at implant loading and at the 1-year follow-up visit.
Results: The results showed statistically significant differences between the two groups in the mean value of keratinized tissue (KT) height after surgery that was significantly reduced for submerged implants when compared with transmucosal implants (mean reduction of KT at year follow-up: T group 0.2 mm, S group 1.3 mm; P =0.007).
Conclusion: Similar outcomes were found for submerged and non-submerged implants placed in fresh extraction sockets with a horizontal peri-implant defect smaller than 2 mm, except for a reduction of KT in the submerged group. Either with a submerged or a non-submerged procedure, 1 mm of mean soft tissue recession is seen after 1 year when compared with the pre-extraction situation.     

Bone regeneration at implants placed into extraction sockets of maxillary incisors in dogs

Aim: To compare the influence of autologous or deproteinized bovine bone mineral as grafting material on healing of buccal dehiscence defects at implants installed immediately into the maxillary second incisor extraction socket in dogs. Material and methods: In the maxillary second incisor sockets of 12 Labrador dogs, implants were installed immediately following tooth extraction. A standardized buccal defect was created and autologous bone particles or deproteinized bovine bone mineral were used to fill the defects. A collagen membrane was placed to cover the graft material, and the flaps were sutured to fully submerge the experimental areas. Six animals were sacrificed after 2 months, and six after 4 months of healing. Ground sections were obtained for histological evaluation. Results: After 2 months of healing, all implants were osseointegrated. All buccal dehiscence defects were completely filled after 2 months irrespective of the augmentation material (autologous bone or Bio‐Oss^®) applied. Bone‐to‐implant contact (BIC) on the denuded implant surfaces was within a normal range of 30–40%. However, the newly formed tissue at 2 months was partially resorbed (>50% of the area measurements) after 4 months. Conclusions: Applying either autologous bone or deproteinized bovine bone mineral to dehiscences at implants installed immediately into extraction sockets resulted in high degree of regeneration of the defects with satisfactory BIC on the denuded implant surface. To cite this article:
De Santis E, Botticelli D, Pantani F, Pereira FP, Beolchini M, Lang NP. Bone regeneration at implants placed into extraction sockets of maxillary incisors in dogs.
Clin. Oral Impl. Res. 22 , 2011; 430–437.     

Immediate provisionalization of dental implants placed in fresh extraction sockets using a flapless technique

The aim of this clinical study was to evaluate the 24-month clinical outcomes of immediate provisionalization of dental implants placed in fresh extraction sockets using a flapless technique. Fifteen patients were included under strict inclusion and exclusion criteria. All patients required one or two teeth to be extracted for lesions with a hopeless prognosis in the maxillary monoradicular or first premolar region. Twenty implants were placed immediately after tooth extraction, and immediate provisionalization was performed. Sixteen implants had a diameter of 5 mm, and four implants had a diameter of 3.80 mm, all with a 13-mm length. After 24 months of follow-up, a cumulative survival rate of 100% was reported for all implants. Modified Bleeding Index (mBI), modified Plaque Index (mPI), probing depth (PD), marginal gingiva level (MGL), and keratinized mucosa (KM) remained stable for up to 24 months. Mean MGL at 24 months was 0.22 ± 0.15 mm; no significant changes occurred in MGL between baseline and 24 months. Mean KM remained stable from baseline to 24 months. At 24 months, a mean bone loss of 0.83 ± 0.52 mm was measured. The results of this study indicate that flapless surgery for immediately provisionalized implants placed in fresh extraction sockets provides soft tissue and marginal bone maintenance for up to 24 months of follow-up.     

Experimental study of osseointegrated dental implants placed into fresh extraction sockets in dogs]

OBJECTIVE: To investigate the better way in treating bone defects around implants. METHODS: 12 mongrel dogs, pure titanium implants were immediately inserted in the mesial roots of the second, third and fourth mandibular premolar sockets. The defects around implants were separately filled with demineralized freeze-dried bone allograft (DFDBA), demineralized freeze-dried allocancellous in combination with bBMP (bBMP compound bone) and nothing. RESULTS: Histologic observation showed that bone defects around implants were substituted by new bone in DFDBA group at 12 weeks and in bBMP compound bone group at 8 weeks, and also the osseointegration were obtained between implants and bone, but bone defects were only filled about 3/5 in no graft group at 12 weeks. CONCLUSION: Immediate implants could obtain good osseointegration if the defects around implants were treated properly and the right technique was used, and also the use of bBMP compound bone could promote obviously bone formation in defects around implants.     

A five-year evaluation of implants placed in extraction sockets

The aim of this study is to examine extraction socket implant longevity and peri-implant conditions longitudinally and to compare the outcome with implants placed in intact alveolar bone sites (nonextraction sites) after a time period in function of five years or more. We hypothesize that implants placed into fresh extraction sockets have a long-term rate of success similar to that of conventionally placed implants. Eleven extraction socket implants in eight patients with a follow-up of at least five years were included in this report. The implants were loaded with either single-tooth replacements or three-to-four-unit fixed partial dentures after healing times of four to six months. Intraoral radiographs of the 11 implants were obtained immediately after surgery and upon recall five to seven years after surgery. In addition, the following clinical parameters were evaluated at each implant site five to seven years postsurgery: plaque indices (PT), bleeding indices (BI), probing depths, attachment level (AL), and distance from implant shoulder to mucosal margin (DIM). As a control, 11 implants from a previous long-term study of nonsubmerged implants placed into intact alveolar bone sites by the same clinician were matched by implant location, sex, and age. Initial and long-term follow-up radiographs of the experimental and control groups were scanned into a computer. A computer program designed for radiographic implant analysis was utilized to examine the changes in radiographic bone levels over time in the two groups. After a period of five to seven years, the mean bone loss for the immediate implant group was 0.167 mm, while that of the control group was 0.460 mm. An unpaired t-test resulted in a P value = 0.0563, indicating that the mean change in bone levels between the two groups is not statistically significant. In addition, clinical evaluation parameters (PI, BI, AL, DIM) revealed no significant difference between the two groups. Therefore, it can be stated that in this study the long-term success rate for extraction socket implants is similar to that of conventionally placed implants.     

Clinical comparison of hydroxyapatite-coated titanium dental implants placed in fresh extraction sockets and healed sites.

The placement of hydroxyapatite-coated dental implants in fresh extraction sockets was compared to placement in adjacent healed sites in 14 patients. Systematic sequential documentation was obtained regarding periodontal health, radiographic bone levels, and implant stability at the time of implant placement, at uncovering, and from 8 to 24 months (mean 16 months) after loading and restoration delivery. There were no significant differences in any clinical parameter between those implants placed in fresh extraction sockets and those placed in healed areas. Periodontal health, maintenance of crestal bone levels, and implant stability were excellent for implants placed in both types of recipient sites. The results of this study suggest that hydroxyapatite-coated dental implants can be successfully placed in fresh extraction sockets utilizing otherwise standard implant placement techniques, and that they appear to clinically perform equally well in fresh sockets and healed sites.     

A 10-year evaluation of implants placed in fresh extraction sockets: a prospective cohort study

Background: The placement of an implant into a fresh extraction socket has been identified as a reliable technique, allowing a reduction in the time needed for prosthetic rehabilitation. This treatment modality is widely reported in the scientific literature; however, the long-term outcomes and the need for guided bone regeneration (GBR) are still topics of debate. The aim of this prospective study is to evaluate the clinical and radiologic findings from the 10-year follow-up of immediately placed implants, with and without the GBR procedure. Methods: A total of 159 implants in 91 patients are included in this study; 101 implants required a GBR procedure simultaneously with placement. All implants were used to support a single crown restoration. The clinical/radiographic measurements were repeated each year up to the 10-year follow-up. At the 10-year follow-up visit, the papilla index and the apico-coronal location of mid-buccal soft tissue positions were recorded. Results: The 10-year cumulative success rate was 91.8% (87.9% in the non-GBR group and 94.1% in the GBR group). The clinical attachment level (CAL) measurements were stable throughout the study, and 82% of the implants showed marginal bone loss (MBL) of 0.6 to 1.5 mm at the 10-year visit; moreover, these two parameters did not show significant differences between the GBR and non-GBR groups. Seventy percent of the implant sites showed acceptable outcomes in terms of interproximal papilla. The facial gingival level was more apical in the non-GBR group than in the GBR group (P <0.05). Conclusions: The present prospective clinical study shows that implants placed in fresh extraction sockets had a high cumulative success rate, namely 91.8% after 10 years. No differences were detected in survival and success rate of implants whether GBR procedures were performed or not. The CAL, MBL, and marginal level of soft tissue measurements were stable throughout the 10-year evaluation.     

Immediate restoration of implants placed into fresh extraction sockets for single-tooth replacement: a prospective clinical study

The aim of the present clinical study was to evaluate the placement of transmucosal implants into fresh extraction sockets and their immediate restoration with temporary crowns. A series of 22 cases with a 12-month follow-up is presented. Twenty-two patients (15 women and 7 men; mean age 39 years) who needed a single tooth replaced because of vertical or horizontal root fracture, caries, endodontic lesions, or periodontal disease were treated with immediate postextraction implant placement. The implant was then restored with a screw-retained prosthetic restoration within 24 hours. Radiographic assessments were made at baseline and 12 months after implant placement. Clinical parameters, such as plaque score, mucositis score, probing attachment level, mucosal margin position, variation of gingival level, and variation of papilla position, were also measured at baseline and after 12 months of follow-up. At 12 months, no implants had failed. Radiographic examination revealed mean bone resorption of 0.5 mm at 12 months compared to baseline. The mean variation of gingival level, compared to the neighboring teeth, was -0.75 mm. Probing attachment levels were 0.79, 0.45, and 0.54 mm at proximal, buccal, and lingual sites, respectively. The values for the mucosal margin position were 2.9, 2.2, and 2.4 mm at proximal, buccal, and lingual sites, respectively. Regarding variation of papilla position, according to Jemt's index, 27 papillae presented with a score of 2 (61%) and 17 with a score of 3 (39%). An examination of oral hygiene and peri-implant soft tissue conditions at the 12-month follow-up visit revealed an overall frequency of plaque-carrying implant surfaces of 13%. Furthermore, mucositis (score 2) was not observed at any of the peri-implant units. Primary implant stability did not significantly increase over time. The immediate restoration of dental implants placed into fresh extraction sockets was shown to be a safe and predictable procedure. The success rate and radiographic and clinical results were comparable to those obtained following the standard protocol. Within the limits of the present investigation, immediate restoration of single-tooth implants placed in fresh extraction sockets can be considered a valuable option to replace a missing tooth. However, long-term clinical trials are needed to confirm the present results.