Influence of autoclavation on the efficacy of extracted tooth roots used for vertical alveolar ridge augmentation

Clinical outcomes following a combined vertical and horizontal alveolar ridge augmentation and two-stage implant placement using either autogenous tooth roots or autogenous bone blocks

AIM

To assess and compare the short-term clinical outcomes following a combined vertical and horizontal alveolar ridge augmentation and two-stage implant placement using either autogenous tooth roots (TR) or autogenous bone blocks (AB).

MATERIALS AND METHODS

A total of n = 27 patients (TR/AB: 13/14) exhibiting n = 31 implants (TR/AB: 14/17) were available for the analysis. Each subject had been allocated to a combined vertical and horizontal alveolar ridge augmentation using either (1) healthy TR (e.g., retained wisdom teeth), or (2) monocortical AB harvested from the retromolar area (i.e. external oblique line). Clinical parameters (e.g., bleeding on probing, BOP; probing pocket depth, PD; mucosal recession, MR) were recorded after a follow-up period of 16.03 ± 4.3 months following implant placement.

RESULTS

The survival rates amounted to 100% in both groups. TR and AB grafted sites were associated with similar changes in mean BOP (8.97 ± 27.73%; 11.90 ± 18.97%), PD (0.53 ± 0.49; 0.47 ± 0.67 mm), and MR (0.03 ± 0.13; 0.0 ± 0.02 mm) values. The incidence of peri-implant mucositis and peri-implantitis at the patient level amounted to 15.38% and 0.0% in the TR-, and 28.57% and 7.14% in the AB group.

CONCLUSIONS

Both surgical procedures were associated with peri-implant tissue health and stability on the short-term.

Efficacy of autogenous tooth roots for a combined vertical and horizontal alveolar ridge augmentation and staged implant placement. A prospective controlled clinical study

OBJECTIVES

To assess and compare the efficacy and safety of autogenous tooth roots (TRs) and autogenous bone blocks (ABs) for combined vertical and horizontal alveolar ridge augmentation and two-stage implant placement.

MATERIALS AND METHODS

A total of 28 patients in need of implant therapy and vertical ridge augmentation were allocated to parallel groups receiving either healthy autogenous tooth roots (e.g., retained wisdom teeth) (n = 14, n = 15 defects) or cortical autogenous bone blocks harvested from the retromolar area (n = 14, n = 17 defects). After 26 weeks of submerged healing, the clinical reduction in ridge height (RH) deficiency was defined as the primary outcome.

RESULTS

Both surgical procedures were associated with a similar mean reduction in RH deficiency values, amounting to 4.48 ± 2.42 mm (median: 4.25; 95% CI: 3.08-5.88) in the TR group and 4.46 ± 3.31 mm (median: 3.00; 95% CI: 2.54-6.38) in the AB group (p = .60, Mann-Whitney U-test). In all patients investigated, the reduction in RH deficiency values allowed for an adequate implant placement at the respective sites. The frequency of complications (e.g., soft tissue dehiscences) was low (TR: n = 4; AB: n = 0).

CONCLUSIONS

Up to staged-implant placement, both TR and AB grafts appeared to be associated with comparable efficacy and safety for combined vertical and horizontal alveolar ridge augmentation.

Bone augmentation with autologous tooth shell in the esthetic zone for dental implant restoration: a pilot study

Objectives

To investigate the outcome and short-term follow-up of autogenous tooth shell (TS) grafting for bone augmentation in the esthetic zone, as well as stability and esthetics of implant-supported restoration.

Materials and methods

A total of 8 patients with 11 implants in 11 sites were enrolled in this study. All the horizontal and/or vertical bone defects in the esthetic zone were augmented by tooth shells, which were fixed laterally to the residual bone with osteosynthesis screws. The gap between the shell and residual bone was filled with Bio-Oss® granules. Four months after bone augmentation, dimensionally sufficient dental implants were inserted and implants-supported prostheses were made 3 months later. The esthetic outcome was evaluated by pink esthetic score (PES) and white esthetic score (WES) one year after prosthetic restoration. Horizontal ridge width (HRW) was assessed before and immediately after bone augmentation, as well as 4 and 19 months post-augmentation by radiography. The stability and absorption of TS grafts were evaluated at the 4th and 19th months post-augmentation.

Results

Though wound dehiscences occurred in 3 cases, secondary healings were obtained after TS modification and irrigation. The other 5 cases went through uneventful healing during the whole observation period. Radiographic examination showed that HRW was 8.01 ± 0.93 mm (median: 7.80, 95% CI 7.38, 8.64) 4 months after TS augmentation, which was statistically different compared to HRW (2.72 ± 1.73 mm) at the baseline. Mean HRW gain was 5.29 ± 2.03 mm (median: 4.60, 95% CI 3.92, 6.66). Three-dimensional bone volume in all the augmented sites was sufficient for dental implants insertion and prosthetic restoration. Follow-up of one year showed stable marginal bone around dental implants. The implant survival rate was 100%. HRW losses were 0.65 ± 0.43 mm (the 4th month) and 1.05 ± 0.54 mm (the 19th month) compared to HRW immediately after augmentation. The PES and WES of final prosthetic restorations were 8.09 ± 0.70 and 8.91 ± 0.54, respectively.

Conclusions

Autogenous tooth shell grafting is a reliable approach for bone augmentation in the esthetic zone for dental implant treatment, allowing for favorable stability and esthetic outcome of implant-supported prosthesis within the one-year follow-up period.

Clinical performance of tooth root blocks for alveolar ridge reconstruction

This systematic literature review set out to investigate the clinical outcomes of autogenous tooth root blocks used for ridge augmentation: survival rates, block resorption, implant survival, post-surgical complications, and histology findings. This review followed PRISMA guidelines. An automated search was made in four databases, supplemented by a manual search for relevant articles published before December 2020. The quality of evidence provided was assessed with the Newcastle-Ottawa Quality Assessment Scale and the Joanna Briggs Institute Critical Appraisal tool. Seven articles fulfilled the inclusion criteria and underwent analysis. The articles included a total of 136 patients, who received 118 autogenous tooth root blocks and 26 autogenous bone blocks showing block survival rates of 99.15% and 100%, respectively. Tooth root blocks presented a mean bone gain that was similar to autologous bone blocks but showed less resorption. The implant survival rate was 98.32% for autogenous tooth root blocks. Reconstruction of alveolar crests by means of autogenous tooth root blocks appears to be a satisfactory option for single-tooth gaps and low grades of bone atrophy in terms of the survival of the bone block and the implants placed subsequently. More research providing long-term data is needed to confirm these findings.

Animal models of vertical bone augmentation (Review)

Vertical bone augmentation is an important challenge in dental implantology. Existing vertical bone augmentation techniques, along with bone grafting materials, have achieved certain clinical progress but continue to have numerous limitations. In order to evaluate the possibility of using biomaterials to develop bone substitutes, medical devices and/or new bone grafting techniques for vertical bone augmentation, it is essential to establish clinically relevant animal models to investigate their biocompatibility, mechanical properties, applicability and safety. The present review discusses recent animal experiments related to vertical bone augmentation. In addition, surgical protocols for establishing relevant preclinical models with various animal species were reviewed. The present study aims to provide guidance for selecting experimental animal models of vertical bone augmentation.

Autogenous Dentin With Calcium Sulfate as Graft Material: A Case Series

There have been recent reports of successful use of fragmented autogenous dentin being used as a graft material in implant dentistry. This may reduce morbidity and the need for a second donor ste or for the use of alloplasts or allografts. This article discusses the background, preparation and use of autogenous dentin as an oral osseous graft material. A series of cases where autogenous dentin is used to graft immediate dental implant sites is presented. After 21 months one case biopsy showed only bone and no remnant dentin. Pulverized autogenous dentin may be an appropriate graft material in implant dentistry.

Microstructural volumetric analysis of vertical alveolar ridge augmentation using autogenous tooth roots

BACKGROUND

To volumetrically assess the bone microstructure following vertical alveolar ridge augmentation using differently conditioned autogenous tooth roots (TR) and second-stage implant placement.

MATERIALS AND METHODS

The upper premolars were bilaterally extracted in n = 4 beagle dogs and randomly assigned to either autoclavation (TR-A) or no additional treatment (TR-C). Subsequently, TR were used as block grafts for vertical alveolar ridge augmentation in both lower quadrants. At 12 weeks, titanium implants were inserted and left to heal 3 weeks. Microcomputed tomography was used to quantify bone volume per tissue volume (BV/TV), trabecular thickness (Tb.Th), and trabecular spacing (Tb.Sp) at vestibular (v) and oral (o) aspects along the implant and in the augmented upper half of the implant, respectively.

RESULTS

Median BV/TV [TR-C: 51.33% (v) and 70.42% (o) vs TR-A: 44.05% (v) and 64.46% (o)], Tb.th [TR-C: 0.22 mm (v) and 0.27 mm (o) vs TR-A: 0.23 mm (v) and 0.29 mm (o)] and Tb.Sp [TR-C: 0.26 mm (v) and 0.13 mm (o) vs TR-A: 0.29 μm (v) and 0.15 mm (o)] values were comparable in both groups.

CONCLUSION

Both TR-C and TR-A grafts were associated with a comparable bone microstructure within the grafted area.

Short-term outcomes of staged lateral alveolar ridge augmentation using autogenous tooth roots. A prospective controlled clinical study

OBJECTIVES

To assess the short-term clinical outcomes of lateral alveolar ridge augmentation using autogenous tooth roots (TR) and autogenous bone blocks (AB).

MATERIAL AND METHODS

A total of n = 23 patients (23 implants) were available for the analysis. Each subject was allocated to lateral ridge augmentation using either (a) healthy autogenous tooth roots (e.g., retained wisdom or impacted teeth; n = 13) or (b) cortical autogenous bone blocks harvested from the retromolar area (n = 10). Clinical parameters (e.g., bleeding on probing-BOP, probing pocket depth-PD, mucosal recession-MR, clinical attachment level-CAL) were recorded at (V8) and after 26 ± 4 weeks (V9) of implant loading.

RESULTS

TR and AB groups were associated with comparable (p > 0.05) changes in mean BOP (-23.0 ± 34.3%; -11.75 ± 24.9%), PD (-0.03 ± 0.14 mm; -0.1 ± 0.29 mm), MR (0.0 ± 0.0 mm; 0.0 ± 0.0 mm) and CAL (-0.03 ± 0.14 mm; -0.1 ± 0.29 mm) values. The regression analysis failed to reveal any significant correlations between changes in BOP and PD values and the initial as well as the ridge width measured at 26 weeks.

CONCLUSIONS

TR and AB were associated with comparable clinical short-term outcomes.