Bone healing after dental extractions in irradiated patients: a pilot study on a novel technique for volume assessment of healing tooth sockets.

The aim of this study was to evaluate longitudinally the bone-healing process by measuring volumetric changes of the extraction sockets in head and neck cancer patients undergoing radiotherapy after tooth extraction. A total group of 15 patients (nine males, six females) undergoing tooth extraction at the Department of Periodontology (University Hospital KULeuven) were enrolled after giving informed consent. In seven patients, teeth presenting a risk for complications and eventual radionecrosis were extracted prior to the radiotherapeutical procedure. Monitoring of bone healing was performed by evaluating the volumetric changes of the alveoli by cone beam CT scanning (CBCT) at extraction and after 3 and 6 months. In parallel, a similar longitudinal evaluation of extraction sites was done in a control group of eight patients. Within this pilot-study, a total of 15 healing extraction sockets were evaluated and followed up. There was a significant difference in volumetric fill up of extraction sockets in test group vs. control group at three (37.1 +/- 7.9%) vs. (54.6 +/- 4.0%) and 6 months (47.2 +/- 8.8%) vs. (70.0 +/- 7.3%), respectively. The present pilot study demonstrated the clinical usefulness of CBCT for evaluation of extraction socket healing. The study objectively demonstrates the delayed bone healing after tooth extraction in irradiated head and neck cancer patients. Considering the limitations of this pilot study, a potential effect of radiotherapy on further jaw bone healing after pre-therapeutic tooth extractions should be further explored.

A biomechanical assessment of the relation between the oral implant stability at insertion and subjective bone quality assessment.

AIM: The study was set to evaluate the validity of subjective jaw bone quality assessment. MATERIALS AND METHODS: A total of 298 patients (198 females, mean age 56.4) were treated with oral implants at the Periodontology Department at the University Hospital of KUL. A total of 761 TiUnite implants have been installed. Subjective bone quality assessment was performed on radiographs and by the surgeon's tactile sensation and was compared with torque measurements. In a subset of patients, implant stability was also assessed by implant stability quotient and/or periotest values. RESULTS: Subjective assessment of bone quality was related to the PTV, ISQ and placement torque [in the crestal, the second and the apical third (N cm)], respectively; in grade 1: -5.3, 73.3 (4.2, 9.6, 15.2), and grade 3 or 4: -1.6, 55 (3.3, 5.5, 8.4). For the surgeon's tactile sensation, a good correlation was noted for the presence of a thick cortex: -4.6, 70.3 (4.2, 9.7, 15.1), or a thin one: -0.3, 65.9 (3.6, 6.9, 10.1). For dense trabecular bone, the values were -2.8, 69.4 (4.4, 9.7,14.8), while for poor trabecular bone, the values were-1.7, 66.4 (3.6, 6.4, 9.8). CONCLUSIONS: Subjective assessment of bone quality is related to PTV, ISQ and placement torque measurements at implant insertion.

Comparison between jaw bone augmentation by means of a stiff occlusive titanium membrane or an autologous hip graft: a retrospective clinical assessment.

OBJECTIVES: Patients in need of bone augmentation procedures can be treated with a traditional hip graft or by neogenesis under a stiff occlusive titanium membrane, custom-fit on the basis of CT-scan data. MATERIAL AND METHODS: Eighteen patients treated by means of a hip graft (H) were compared with 11 patients using a full titanium membrane (M) for the rehabilitation of upper jaws. In the H group, 17 patients (62 implants) in the anterior region (Ha) and 14 patients (23 implants) in the posterior region (Hp) were included. In the M group, nine patients (30 implants) in the anterior region (Ma) and seven patients (16 implants) in the posterior region (Mp) were included. RESULTS: In group Ha, the CFR was 13.3% after 14 years compared with group Ma where the CFR was 17.4% after 9 years. In group Hp, the CFR was 22.8% after 16 years compared with group Mp where the CFR was 23.4% after 6 years. The marginal bone loss for group Ha after 20 years was 2.7 mm, for group Ma it was not even 1 mm after 9 years; for group Hp, it was 2.5 mm after 15 years compared with less than 1 mm after 3 years in group Mp. CONCLUSIONS: The success rate of alveolar ridge augmentation therapy is lower than in a classical approach. These augmentation procedures, however, show acceptable results. The titanium membrane augmentation leads to less marginal bone loss probably because neo-formed bone has a better chance to adapt its mineralization to occlusal forces encountered. This technique could offer improvement if membrane exposure can be avoided.

Patient evaluation of a novel non-injectable anesthetic gel: a multicenter crossover study comparing the gel to infiltration anesthesia during scaling and root planing.

BACKGROUND: Periodontal scaling procedures commonly require some kind of anesthesia. From the patient's perspective, the choice of anesthetic method is a trade-off between the degree of anesthesia and accepting the side effects. The present study evaluates the preferences for a novel non-injection anesthetic product (a gel, containing lidocaine 25 mg/g plus prilocaine 25 mg/g and thermosetting agents) versus injection anesthesia (lidocaine 2% adrenaline) in conjunction with scaling and/or root planing (SRP). METHODS: In a multicenter, crossover, randomized, open study patients were asked, after they had experienced both products, if they preferred anesthetic gel or injection anesthesia. In addition, the adequacy of anesthesia and occurrence of post-procedure problems were assessed. The patients were also asked about their willingness to return if they were offered anesthetic gel at their next visit and their maximum willingness to pay (WTP) for this option. RESULTS: One-hundred seventy (170) patients at eight centers in Belgium were included in the study. There were 157 per protocol (PP) patients. A vast majority of the PP patients (70%) preferred the anesthetic gel to injection anesthesia (22%). The most common reason was less post-procedure numbness. Eighty percent (80%) of the patients expressed satisfactory anesthesia with the gel and 96% with injection anesthesia (P <0.001). Post-procedure problems were significantly less with the gel than with injection (P <0.001): numbness 15% versus 66%, unpleasant sensations such as soreness and pain 44% versus 63%, and problems connected with daily activities 19% versus 69%. The majority of patients (60%) who preferred gel were also willing to pay for it. A conservative estimate of the median WTP was $10.00. Furthermore, anesthetic gel would make almost every second patient (45%) more or much more willing to return for the next treatment. CONCLUSIONS: The data suggest that a somewhat less profound anesthesia with gel is clearly preferred by the patients because of the low incidence of post-procedure problems as compared to conventional injection anesthesia. The median WTP is likely in excess of the acquisition cost of the product, which indicates a favorable cost-benefit ratio for the individual patient.

Clinical assessment and surgical implications of anatomic challenges in the anterior mandible.

BACKGROUND: The anterior mandible is generally considered a rather safe surgical area, involving few risks of damage to vital anatomic structures. Nevertheless, both neurosensory disturbances and hemorrhages have been reported after implant surgery in that particular area. PURPOSE: With the increasing demand for oral implant placement, the anatomy of the anterior mandible should receive more attention. This review will focus on the anatomic peculiarities of the anterior mandible and the related clinical implications. METHODS: The scientific evidence on the anatomic, histologic, physiologic, and clinical aspects of the neurovascularization of the anterior mandible will be reviewed. RESULTS: Surgical complications may be attributed to the existence of a mandibular incisive canal with a true neurovascular supply. Potential risks may also be related to the presence of the lingual foramen and anatomic variations, such as an anterior looping of the mental nerve. CONCLUSIONS: Preoperative radiographic planning for oral implant placement in the anterior mandible should therefore not only consider all esthetic and functional demands but should also pay particular attention to the anatomic peculiarities of this region to avoid any neurovascular complications.