Marginal Bone Level and Bone Thickness Reduction in Delayed and Immediate Implant Placement Protocol 6 Months Post-loading: An Observational Clinical Prospective Study.

Objectives: The aim of this prospective study was to assess marginal bone level (MBL), buccal and palatal bone thickness reduction (BTR) around implants in delayed and immediate placement protocols, 6 months after loading. Materials and Methods: Twenty-four patients were assigned to two treatment groups, and treated with an immediate (Test) or delayed implant placement (Control). Baseline and 6 months post-loading periapical and Cone Beam Computed Tomography radiographs were used to measure mesial, distal, buccal, and palatal MBL change, and buccal and palatal BTR. Results: There was no statistically significant difference between groups, in MBL change, mesially (p = 0.4220), distally (p = 0.774), buccally (p = 0.221), and palatally (p = 0.195). There was more MBL change on the buccal side than on the palatal side in both groups, control (p = 0.012) and test (p = 0.005). Buccal bone thickness decreased significantly in both groups, and at all four levels (p < 0.05). Buccal BTR was higher in test implants at 0, 2, and 4 mm (p = 0.005, p = 0.0018, p = 0.006) on the buccal side, and at 0 mm (p = 0.006) on the palatal side. Implant stability increased in both groups (p < 0.001). A positive correlation was found between insertion torque and stability in the control group (p = 0.024). Conclusions: Within the study limitations, MBL changes occur around implants and are comparable between groups. More buccal than palatal MBL change occurs in both groups. Buccal BTR is higher in immediate cases. Implant stability augmented in both groups. Clinical Relevance: This data call for additive therapy to compensate for the expected bone loss, particularly in esthetically demanding cases. Trial Registration: ClinicalTrials.gov Identifier: NCT04346706 Registered 14 April 2020 - Retrospectively registered, http://www.clinicalTrials.gov.

Alveolar Ridge Preservation on Maxillary Molars Using Solvent Dehydrated Bone Allograft and d-PTFE Membrane: A CBCT and Histologic Human Pilot Study.

The purpose of this study was to evaluate vertical and horizontal alveolar resorption after the extraction of eight single maxillary molars using solvent-dehydrated bone allograft (Puros) covered with a nonresorbable membrane for ridge preservation. At implant placement 4 months later, ridge dimensions were measured clinically and radiographically and compared to baseline, and a histologic analysis was performed. The mean buccal height decreased by 1.51 mm at midpoint, 0.88 mm mesially, and 1.16 mm distally. The implants were placed without additional ridge augmentation, and six of eight required an internal sinus elevation. Within the limits of this study, this technique succeeded in preserving the alveolar bone.

Prevalence of Interproximal Contact Loss Between Implant-Supported Fixed Prostheses and Adjacent Teeth and Its impact on Marginal Bone Loss: A Retrospective Study.

PURPOSE: To investigate the prevalence of interproximal contact loss between implant-supported fixed prostheses and adjacent teeth and its impact on marginal bone loss and to identify potential risk factors. MATERIALS AND METHODS: Patients who received implant-supported fixed prostheses at Saint-Joseph University between the years 2011 and 2017 and met the inclusion/exclusion criteria were eligible to participate in this retrospective study. Interproximal contacts were evaluated with a 70-µm dental floss and confirmed visually and by periapical radiographs. Contact was considered open if the floss passed without resistance. Plaque Index and bleeding on probing were assessed, and radiographic bone loss around implants was measured at recall. RESULTS: Eighty-three patients (183 interproximal contact points) were evaluated. Interproximal contact loss between implant-supported fixed prostheses and adjacent teeth occurred in 32.8%; among mesial contact points, 42.1% had interproximal contact loss, whereas 14.5% had interproximal contact loss on the distal side. In interproximal contact loss sites, a mean marginal bone loss of 0.73 mm was noted; the difference was statistically significant compared with marginal bone loss at sites with interproximal contact (P = .017). Age, sex, smoking status, periodontal status, implant sites, and the type of restoration were not significantly associated with interproximal contact loss or marginal bone loss. Sites with interproximal contact loss were 2.24 times more likely to present bleeding on probing than others. CONCLUSION: Interproximal contact loss occurred in 32.8% of implant-supported fixed prostheses, and a positive relationship between interproximal contact loss and marginal bone loss was found, which suggests that interproximal contact loss should be included as a prosthetic implant complication. Future research aiming at identifying the causative factor for interproximal contact loss is necessary.

Long-Term Follow-up of Iatrogenic Implant Endodontitis: A Case Report.

An undesirable injury of adjacent teeth is one of many accidents that may occur during implant placement. Limited surgical access in a noncooperative patient can induce apical root transection. When endodontic pathosis is identified, root canal treatment is often initiated to prevent implant microbial contamination. This case report demonstrates the successful resolution of implant endodontitis by endodontic intervention without any surgical treatment in a patient presenting a moderate mental disorder.

Influence of the Maxillary Sinus on the Accuracy of the Root ZX Apex Locator: An Ex Vivo Study.

This study evaluated the accuracy of the Root ZX (J. Morita, Tokyo, Japan) electronic apex locator in determining the working length when palatal maxillary molar roots are in a relationship with the sinus. Seventeen human maxillary molars with vital pulp were scheduled for an extraction and implant placement as part of a periodontal treatment plan. The access cavity was prepared, and a #10 K file (Dentsply Maillefer, Ballaigues, Switzerland) was inserted into the palatal root using the Root ZX apex locator in order to determine the electronic working length (EWL); then, the teeth were extracted. To determine the real working length (RWL), a #10 K file was introduced into the root canal until its tip touched a glass plate. EWL and RWL were compared. Images reconstructed with CBCT (cone beam computerized tomography) revealed that eight palatal roots were related to the maxillary sinus, whereas nine were not. The results showed a significant difference between the EWL and the RWL of the palatal roots related to the sinus (p < 0.001). No significant difference was observed in measurements of roots not in contact with the sinus (p > 0.05). Within the study limitations, the reliability of Root ZX was influenced by the relationship of the roots with the maxillary sinus.

Root Resection and Hemisection Revisited. Part I: A Systematic Review.

Root resection and hemisection is a treatment option for furcated molars, and the prognosis of this technique has been well documented. The aim of the present paper is to systematically review studies examining the survival and/or failure rate of root resection and hemisection and to determine the factors behind the variability in the outcome reported. A Medline (PubMed), Embase, and Google Scholar search was undertaken, looking for articles published up to September 2016. A total of 1,012 publications were screened. Two reviewers analyzed the articles and extracted the data. Case series studies required a minimum of 5 cases, and all levels of evidence were accepted. A total of 22 studies met the inclusion criteria. Survival rate and follow-up times differed widely: survival rate ranged from 40.3% to 100% and follow-up from 6 months to 23 years. Half of the studies had a survival rate > 90% with a follow-up period ranging from 5 to 23 years. Therefore, root resection and hemisection are associated with high survival rates, making it a reliable option for treatment of furcated molars that should be considered before every extraction and implant placement. In a great number of studies, incomplete information was found concerning case selection and endodontic, restorative, and maintenance therapy, which makes one question the obtained results and the occasional reports of low survival rates. These concerns should encourage more detailed, long-term clinical trials, with respect to each phase requirement for the procedure, for a better assessment of survival rate.

Root Resection and Hemisection Revisited. Part II: A Retrospective Analysis of 195 Treated Patients with Up to 40 Years of Follow-up.

Root resection and hemisection is a well-documented treatment option for extending the life span of furcated molars. The aim of the present study was to retrospectively evaluate the long-term results of root resection and hemisection of 195 patients with up to 40 years of follow-up. Records of 195 patients who had undergone root resection or hemisection were reviewed. A minimum follow-up of 5 years was needed. A molar was recorded as a survival if it was still present and functional without any signs of discomfort, pain, or pathology from restorative, endodontic, and periodontal points of view. Ninety-eight patients were excluded for not accomplishing the minimum 5-year observation period. Of the 97 remaining patients, 5 teeth were lost during the first 5 years of treatment and 92 teeth survived the follow-up period, ranging from 5 to 40 years. The overall survival rate was 94.8%. When up to 40 years of follow-up data were analyzed, it was found that high survival rates can be obtained with root resection and hemisection. The results are satisfying when a proper case selection, endodontic treatment, restorative design, and good maintenance program are given. This treatment option should always be considered before every extraction and implant placement.

Effect of Primary Stability and Soft- and Hard-Tissue Thickness on Marginal Bone Loss: A Prospective Pilot Study.

OBJECTIVE: To compare prospectively the effect of different insertion torques (ITs) on marginal bone stability and study the effect of soft-tissue and buccal bone thickness as confounding factors while using a 3-dimensional radiographic evaluation. MATERIALS AND METHODS: Thirty-nine implants were placed in 22 patients. IT, soft-tissue thickness, and buccal bone thickness were recorded at implant placement. Marginal bone loss was evaluated on individualized periapical radiographs and cone-beam computed tomography at 1 year after loading. RESULTS: Three groups of implants emerged based on their IT: group I (<30 Ncm), group II (between 30-45 Ncm), and group III (>45 Ncm). Soft-tissue thickness was ≤2 mm in 10 implants (25.6% thin biotype) and more than 2 mm in 29 implants (74.4% thick biotype). No significant difference in marginal bone loss was found for different IT and different soft-tissue thickness. A significant correlation was found between initial buccal bone thickness (≥2 mm or <2 mm) and marginal bone loss at 1 year. CONCLUSIONS: IT and mucosal tissue thickness did not influence marginal bone loss. Buccal bone thickness of ≥2 mm was associated with a minimal marginal bone remodeling.

Oral Rehabilitation of a Severe Periodontally Involved Patient with Mucous Membrane Pemphigoid: A 15-Year Follow-Up Case Report.

Mucous membrane pemphigoid (MMP) refers to a group of chronic autoimmune subepithelial diseases distinguished by erosive lesions of the mucous membranes and skin. Its treatment consists of inhibition of the inflammatory reaction by means of corticosteroids and symptomatic medication. This is a report of a patient suffering from a combination of MMP and severe generalized chronic periodontitis. The patient has been treated with oral corticosteroids, initial phase therapy, extraction with immediate implant placement, and periodontal surgery where the prognosis was questionable. The case has been followed up for 15 years. Periodontal therapy with immediate implant placement was determined to be a viable modality to achieve a total rehabilitation of a case suffering from MMP combined with severe generalized chronic periodontitis.

Buccal Bone Thickness Overlying Maxillary Anterior Teeth: A Clinical and Radiographic Prospective Human Study.

OBJECTIVES: The aim of this work was to measure the facial bone thickness overlying maxillary anterior teeth according to the periodontal biotype, the tooth position, and the bucco-palatal inclination of the tooth. MATERIALS AND METHODS: CBCTs of 47 patients were included. The periodontal biotype and the bucco-palatal inclination were examined for all maxillary anterior teeth as well as the sagittal tooth position according to the classification of Kan et al. Buccal bone thickness was measured at 4, 6, 8, and 10 mm apical to the cement-enamel junction (CEJ). RESULTS: At 4 mm from the CEJ, mean buccal bone thickness was 1.0 mm for all teeth and it decreased gradually and significantly in apical direction (6, 8, and 10 mm). A thin biotype was associated with a labial plate thickness half that of a thick biotype at all 4 distances from the CEJ. Class IV of Kan et al classification presented the thinnest facial bone (0.32-0.54 mm), whereas Class III demonstrated the thickest one (1.26-2.09 mm) at all distances from the CEJ. At 10 mm from the CEJ, the facial bone thickness increased with the vestibulo-palatal inclination of the tooth. CONCLUSION: A thin facial bone wall overlies almost all maxillary anterior teeth.

Resonance frequency analysis, insertion torque, and bone to implant contact of 4 implant surfaces: comparison and correlation study in sheep.

INTRODUCTION: Primary stability is evaluated using resonance frequency analysis (RFA) and insertion torque (IT). Although there is a strong correlation between RFA and IT, studies failed to find a correlation between RFA and bone to implant contact (BIC) or IT and BIC. OBJECTIVE: To compare RFA, IT, and BIC of SLA, SLActive, Euroteknika, and TiUnite implant surfaces and evaluate the correlation between them. MATERIALS AND METHODS: Thirty-two implants were placed in 8 sheep. RFA and IT were recorded. Animals were killed at 1 and 2 months. RESULTS: A significant difference was found in RFA between the 4 surfaces. No significant difference was found for IT. Mean BIC was different between all 4 surfaces. A significant positive correlation was found between RFA and IT with SLA. No significant correlation was found between RFA and BIC and between IT and BIC at 1 and 2 months. CONCLUSIONS: Implants with 4 different surfaces have similar IT values but different RFA and BIC. Additionally irrespective of the implant surface, there is no correlation between IT and BIC and between RFA and BIC.

Peak insertion torque correlated to histologically and clinically evaluated bone density.

OBJECTIVE: : Establish a correlation between dental implant insertion torque (IT) and bone density. MATERIALS AND METHODS: : In 18 patients, implant site preparation was initiated using a trephine drill to retrieve a bone biopsy and completed with standard drills. Bone type was assessed during drilling according to surgeon's tactile sense. Forty implants were placed and peak IT values were recorded. Osseointegration was evaluated clinically at abutment connection. Data were analyzed using Pearson product-moment correlation coefficient. RESULTS: : All implants but one achieved osseointegration. D1 and D4 bone types were significantly assessed using tactile sense. IT values ranged from 15 to 150 Ncm with a mean value of 78.30 Ncm. Mean IT was significantly higher in D1 bone (126.67 Ncm) and lower in D4 bone (40.22 Ncm) (P value <0.0001), whereas intermediate values were noted in D2 and D3 bone with no significant difference between these bone types (P value = 0.462). Statistically significant correlation was found between bone volume and IT values (r = +0.771, P < 0.0001). No statistically significant correlation was found between implant length and/or diameter and IT in all bone densities. CONCLUSION: : Clinical assessment of bone density during drilling may be achieved in hard and soft bone but not in intermediate densities. Increasing peak IT values correlated with increasing bone volume. High IT does not seem to alter osseointegration process.

[Amalgam, composites and compomers: a comparative histologic study of periodontal tissues (Part 2)]. / Amalgames, composites et compomeres: étude histologique comparative sur les tissus parodontaux (2è me partie).

Violation of the biologic width could induce different periodontal consequences depending on many factors such as the type of the restorative material used. In this study, the histological performance and the marginal adaptation of three filling materials (amalgam, composite resin and compomer) are evaluated after a period of three months. Class V cavities with apical margin located at the alveolar bone crest were prepared on Pointer dogs teeth and restored with these three materials. Histological analysis showed that lesions in epithelial attachment were mainly noticed with amalgam fillings and the scale of inflammatory cells was the highest when amalgam was used. Compomer showed the best marginal adaptation.

[Amalgam, composites and compomers: comparative histologic study of effects on the periodontal tissues]. / Amalgames, composites et compomères: etude histologique comparative sur les tissus parodontaux.

Amalgam, composite resin and compomer are frequently used in operative dentistry today. Earlier studies have shown the periodontal consequences induced by these materials if they have intracrevicular restorative margins. This study was performed on dogs where Class V cavities with apical margin located at the alveolar bone crest were prepared and restored with these materials. Three months later, the experimental and control sites were prepared for histological analysis. Mean bone loss was significant only with compomer. The mean length of the supracrestal connective tissue was almost the same with the three fillings. The length of epithelial attachment was the highest with composites. There was a decrease in the length of the biologic width from Day 0 to Day 90.

Combined bone grafting and orthodontic treatment of an iatrogenic periodontal defect: a case report with clinical reentry.

BACKGROUND: This case report discusses the treatment of an iatrogenic periodontal defect caused by an inadequate orthodontic appliance in a 9-year-old girl. METHODS: The multidisciplinary approach to this case consisted of periodontal treatment using a bone grafting technique to restore the 10 mm bone dehiscence. Three months later orthodontic treatment was initiated to straighten and level the central incisors. Six months later mucogingival surgery was performed to cover 2 to 3 mm gingival recession. RESULTS: The bony defects were completely filled and the 10 mm dehiscence was reduced to 4 mm. The connective tissue graft resulted in a complete coverage of the recessions and a thickening of the keratinized gingiva. The patient is still undergoing orthodontic treatment. So far, straightening of the upper central incisors and closure of the diastema are satisfactory. CONCLUSIONS: Inadequate orthodontic appliances can cause iatrogenic periodontal defects. A multidisciplinary approach in a well-defined sequence can restore lost periodontal tissue, thus achieving comfort, function, and esthetics.