Association between ridge morphology and complexity of implant placement planning in the posterior mandible

Advancements in dental implantology: The alveolar ridge split technique for enhanced osseointegration

The alveolar ridge split (ARS) technique is a pivotal advancement in dental implantology, addressing the limitation of insufficient bone width for implant placement. This review traces the historical development of ARS from its initial conceptualization to current practices and future directions. Emphasizing the technique's development, indications, procedural overview, and osteotomy variations, we highlight its minimally invasive nature, which reduces patient morbidity and treatment time. This article reviews various osteotomy methods within ARS, examining their applications, benefits, and limitations. Furthermore, it discusses the technique's role in expanding treatment options for patients with compromised alveolar structures, underpinned by a high implant survival rate and the potential for immediate implant placement. We also cover the necessity of meticulous surgical technique, the importance of patient-specific factors, and the promising future of ARS facilitated by advancements in biomaterials and regenerative medicine. In summary, this review provides a comprehensive overview of ARS, offering valuable insights for dental professionals and informing future clinical practices and research in implantology.

Feasibility of implant placement in healed mandibular molar sites: A retrospective cone beam computed tomography study

STATEMENT OF PROBLEM

Implant placement in the mandibular molar sites plays a crucial role in the restoration of edentulous mandibles. However, the evaluation of bone quantity before implant surgery using cone beam computed tomography (CBCT) is lacking.

PURPOSE

The purpose of this clinical study was to evaluate CBCT images of edentulous patients to analyze the feasibility of implant placement in healed mandibular molar sites.

MATERIAL AND METHODS

The CBCT data of 138 patients were analyzed in the sagittal plane for measurements of mandibular bone height (MBH), superior bone height (SBH), inferior bone height (IBH), buccal bone width (BBW), lingual bone width (LBW), and alveolar bone widths (ABWs). The edentulous sites were categorized according to the bone quantity and complexity of the implant surgery. Multivariate analysis of variance (MANOVA) was used to analyze the site, sex, and age-related variations. An independent t test was used to compare the difference of bone dimension in different sites and between sexes. One-way ANOVA followed by post hoc tests were used to analyze the difference between different age groups. Categorical variables were presented as number of events and percentages. The chi-squared test was used to compare categorical variables (α=.05).

RESULTS

A total of 534 sites of interest were recorded, including 274 hemimandibles. A significant difference in BBW was found between the first and second molar sites. Men had higher MBH, SBH, IBH, and BBW than women. The distribution of implant surgical complexity in the conventional group was 63.5%, while the buccolingual tilted implant group accounted for 17.0%, and the complicated group accounted for 19.5%. Of the 274 hemimandibles, an implant could be placed directly at molar sites in 88% of situations.

CONCLUSIONS

The BBW at the mandibular second molar site was greater than that at the first molar site. The amount of available bone in the SBH and BBW was greater in men than in women at the healed molar sites. Age did not significantly affect the complexity of the implant surgery. Implants can be placed directly in healed mandibular molar sites in most patients who require a complete arch mandibular implant-supported restoration.

A biologically oriented preparation technique (BOPT) for immediate posterior implant placement, immediate provisionalization, and definitive implant crown fabrication: A complete digital workflow

OBJECTIVE

Immediate implants and immediate alveolar sealing have been a widely utilized treatment with high predictability and biological advantages. The improvement in technology has made it possible to simplify clinical processes. The aim of the present report was to describe the complete digital workflow of the Biologically oriented preparation technique for immediate posterior implant, immediate provisionalization and fabrication of definitive implant crowns.

CLINICAL CONSIDERATIONS

The surgical process and prosthetic management to preserve the gingival contours of the extracted natural tooth during immediate implant placement and provisionalization are described. Additionally, during the same clinical intervention, the definitive intraoral digital implant scans for capturing the implant position, peri-implant tissue contours, adjacent and antagonist dentition, and profile emergence of the interim implant crown are captured for the fabrication of the definitive crown.

CONCLUSIONS

Based on the technique described, the immediate implant placement and provisionalization in the posterior area provides biological and clinical advantages, reducing the number of abutment-implant disconnections and the number of clinical appointments, as well as increases patient comfort.

CLINICAL SIGNIFICANCE

The present article describes a technique for an immediate implant placement and provisionalization in the posterior region for maintaining the gingival architecture of the extracted tooth. During the same appointment, the implant position, peri-implant tissue contours, and adjacent and antagonist dentition, and profile emergence of the interim implant crown are captured by using an intraoral scanner and used for the fabrication of the definitive crown. This technique aims to reduce the number of abutment-implant disconnections and clinical appointments.

Accuracy of dental implant placement using static versus dynamic computer-assisted implant surgery: An in vitro study: Accuracy of static vs. dynamic CAIS

OBJECTIVES

This in-vitro study compared the accuracy of implant placement using static versus dynamic computer-assisted implant surgery (CAIS) at two implant sites.

METHODS

Partially edentulous maxillary models were 3D-printed, and two implants (Straumann TL RN4.1 × 10mm) were inserted in FDI positions 15 and 16 per model using two CAIS approaches (10 models per approach). A three-dimensional (3D) reconstruction tool was used for implant planning, surgical guide design, and measuring implant positioning accuracy. In static CAIS, the implants were placed with 3D-printed surgical guides (n=20); in dynamic CAIS, real-time navigation was performed (n=20). Primary outcomes were defined as coronal and apical global deviation as well as angular deviations and deviation comparison between implants placed at positions 15 and 16; the secondary outcome was the bi-directional deviation in mesial-distal, buccal-palatal, and apical-coronal direction.

RESULTS

The mean±SD 3D-deviation at implant platform and apex levels for static CAIS in position 15 was 0.81±0.31mm, 1.41±0.37mm, and in position 16 was 0.67±0.31mm, 1.07±0.32mm.

PRIMARY OUTCOMES

buccal-palatal deviation is higher using static CAIS, and mesial-distal deviation is higher in dynamic CAIS. In position 15, mesial-distal deviation at the apex and the platform were lower in static approaches than in dynamic ones. In implant position 16, buccal-palatal deviation at the apex was lower in the dynamic group than with static ones.

SECONDARY OUTCOMES

for bi-directional analysis, buccal-palatal deviation at the platform (P=0.0028) and mesial-distal deviation at the apex (P=0.0056) were significantly lower in molar sites using static CAIS. Mesial-distal deviation at the apex (P=0.0246) revealed significantly lower values in position 16 following dynamic CAIS.

CONCLUSIONS

Both static and dynamic CAIS resulted in accurate implant placement. However, dynamic CAIS exhibited higher deviation in the mesial direction in an in-vitro setting. In addition, the implant site affects the accuracy of both CAIS approaches.

CLINICAL SIGNIFICANCE

Static CAIS demonstrates the highest accuracy for guided implant placement today.

Effects of Crest Morphology on Lingual Concavity in Mandibular Molar Region: an Observational Study

Objectives

The aim of this radiological study is to evaluate the lingual concavity dimensions and possible implant length in each posterior tooth region according to posterior crest type classification by using cone-beam computed tomography.

Material and Methods

According to inclusion criteria, 836 molar teeth regions from 209 cone-beam computed tomography images were evaluated. Posterior crest type (concave, parallel, or convex), possible implant length, lingual concavity angle, width, and depth were recorded.

Results

In each posterior tooth region, concave (U-type) crest was detected most frequently while convex (C-type) was the lowest. Possible implant length values were higher in second molar regions than first molars. Lingual concavity width and depth were decreasing from second molars to first molars for both sides. Additionally, lingual concavity angle showed higher values in second molar sites than first molars. In all molar teeth regions, lingual concavity width values were the highest in concave (U-type) crest type while they were the lowest in convex (C-type) crest type (P < 0.05). Lingual concavity angle values were recorded as the highest in concave (U-type) and the lowest in convex (C-type) crest type at the left first molar and right molars (P < 0.05).

Conclusions

The lingual concavity dimensions and possible implant length may vary according to crest type and edentulous tooth region. Due to this effect, the surgeons should examine crest type clinically and radiologically. All parameters in the present study are decreasing while moving from anterior to posterior as well as from concave (U-type) to convex (C-type) morphologies.