Periodontal Classification Revisited: The Classification System in the Test of Time.

At the EuroPerio conference held in Amsterdam in 2018, an update to the previous classification of periodontal diseases was presented. The update was a joint effort of the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP). On the face of it, the new classification system for diagnosing periodontal diseases and conditions is merely an update of previous definitions from 1999. However, upon close examination, it is much more than another semantic change of old definitions. The new classification rocks the ground upon which generations of pre- and post-graduate students and specialists in the field have stood. It is a perceptual change in the way clinicians describe, diagnose, and ultimately treat periodontal patients.

Periodontal status of males attending an in vitro fertilization clinic.

AIMS: An association has been demonstrated previously between periodontal diseases and various systemic conditions, including endometriosis. A possible role of dental infection in male infertility was also suggested. The aim of the present study was to examine the association between fertility parameters and the periodontal status of men attending a fertility and in vitro fertilization (IVF) clinic. METHODS: The study population consisted of 75 men attending the clinic for sperm analysis before homologue semen insemination or IVF. The quality of sperm was assessed according to WHO criteria. On the same day, patients received a clinical periodontal examination. RESULTS: The patients were diagnosed with either gingivitis (40%) or periodontitis (48%), whereas the remaining 12% were classified as "periodontally healthy". Normospermia was attributed to 37%, oligozoospermia to 48% and azoospermia to 15% of these patients. Familial infertility was significantly associated with having at least one WHO parameter contributing to infertility. A higher number of sites with deep periodontal pockets tended to associate positively with sperm sub-motility. Clinical attachment levels were significantly associated with sperm sub-motility. CONCLUSIONS: These findings may point to a possible association between male infertility, diminished semen quality and periodontal infections in men attending fertility and IVF clinics.

Sinus floor augmentation using large (1-2 mm) or small (0.25-1 mm) bovine bone mineral particles: a prospective, intra-individual controlled clinical, micro-computerized tomography and histomorphometric study.

OBJECTIVES: To compare the amount of newly formed bone after sinus floor augmentation with two different particle sizes of bovine bone mineral (BBM) using clinical, micro-computerized tomography (CT) and histological techniques. METHODS: Bilateral sinus floor augmentations were performed in 10 patients. Six to 9 months later, bone samples were retrieved and analyzed. RESULTS: Results: Both groups were not different in vertical bone height achieved after augmentation, post-operative complications and maximal torque for the insertion of implants. Micro-CT measurements could not detect a statistically significant difference in bone volume between the groups (with a tendency for new more bone in the small granules group). Histomorphometric analysis revealed that both granule sizes produced the same pattern of bone formation, surrounding the graft granules, and producing a shape of a network, "bridging" between the BBM particles. Multi-nucleated giant cells, probably osteoclasts, were observed directly on the BBM particle surface in both groups. The osteoclast-like cells preferred the small-size BBM particles and not the large particles both in the small-size and the large-size granules group. CONCLUSION: Both sizes of BBM granules preformed equally and achieved the aim of the sinus floor augmentation procedure clinically and histologically.

In vivo degradation of collagen barrier membranes exposed to the oral cavity.

OBJECTIVES: The purpose of this human clinical trial was to compare the degradation profiles of three different collagen membranes under conditions mimicking exposure to the oral cavity. MATERIALS AND METHODS: Three collagen membranes, ribose cross-linked (RCL), glutaraldehyde cross-linked (GCL), and non-cross-linked (NCL) were tested. The membranes were placed over the buccal mucosa of 20 human volunteers, apical to the gingival margins in the maxillary premolar and molar region. A periodontal dressing was placed over the membranes and secured in the interproximal spaces. The dressing was removed after 10 days, and membrane integrity was evaluated by two examiners using a Likert-like grading scale (grades 1-5). RESULTS: Eight subjects withdrew from the study due to discomfort, pain, or dislodging of the pack. Of the three membranes tested, RCL appeared to be the most resistant to degradation (median grade 5), compared with GCL (2.25) and NCL (1.75). CONCLUSIONS: Marked differences in membrane integrity were found between the three tested membranes after 10 days in the oral cavity. These differences may be part of the important factors determining the outcome of the regenerative treatment modality in cases of premature membrane exposure.

Effect of a niobium-containing titanium alloy on osteoblast behavior in culture.

BACKGROUND: The chemistry of titanium is a key factor in determining implant-tissue interactions. Reports that a vanadium-based titanium alloy (Ti-6Al-4V) exhibits some cytotoxicity led to a search for an alternative. AIM: The aim of the present study was to investigate the behavior of human osteoblast-like cells (Saos-2) cultured on Ti-6Al-4V or Ti-6Al-7Nb disks with a rough or a machined surface. RESULTS: In all four groups, the cells proliferated rapidly between days 1 and 3, and then plateaued. On day 1 of culture, the highest proliferation rate was of cells cultured on disks containing Nb with a machined surface. On day 7, there was no significant difference in cell density on all the tested surfaces. Alkaline phosphatase (ALP) activity was lower on the machined surfaces, regardless of the material used, suggesting that cells on rough surfaces exhibit a more mature phenotype. On day 3, cells cultured on rough disks made of Ti-6Al-7Nb showed the highest ALP activity; the lowest activity was observed on the machined Ti-6Al-4V surface. The highest level of osteocalcin (day 7) was found in the cells cultured on rough Ti-6Al-7Nb disks. Also, higher levels of transforming growth factor (TGFbeta) were noted for cells cultured on the rough Ti-6Al-7Nb disks, suggesting that the Nb-containing alloy supports more rapid maturation of the osteoblast. CONCLUSIONS: The results of the present study suggest that according to our cell culture preclinical model, Ti-6Al-7Nb may replace the Ti-6Al-4V alloy as an implant material.

Evaluation of the width of the alveolar bone in subjects with different gingival biotypes: A prospective cohort study using cone beam computed tomography.

OBJECTIVE: To examine the correlation between the gingival biotype and the morphology of the alveolar bone in human subjects, assessing the clinical and the practical values of these findings. METHOD AND MATERIALS: Thirty-five subjects were enrolled. The labial plate thickness was measured by cone beam computed tomography (CBCT). The correlation between CBCT and probe transparency measurements was analyzed with regard to tooth type (canine or central incisor). Additional data analysis included possible correlation to gender and smoking status. RESULTS: Of the patients, 57% (20/35) were female; 23% (8/35) were smokers; 78% (25/32) of maxillary teeth had thin biotype compared to 50% (19/38) of mandibular teeth; 63% (10/16) and 32% (6/19) of the patients had thin biotype in maxillary and mandibular teeth respectively. More than 30% of the subjects demonstrated different biotypes in the same jaw at different sites. The probe transparency through the soft tissue at the maxillary canine was positively correlated with the width of the facial bone plate at the alveolar crest (P = .026). CONCLUSION: Biotype can vary in the same subject at different sites. Only the maxillary canine's biotype correlated with the facial plate width.

Alveolar Bone Morphology Following Periodontally Accelerated Osteogenic Orthodontics: A Clinical and Radiographic Analysis.

The aim of this study was to analyze alveolar bone morphology following periodontally accelerated osteogenic orthodontics. Treated patients were called for a full periodontal examination and a cone beam computed tomography scan. Mean treatment time was 6.08 months. Mean probing pocket depth was 2.7 mm. No gingival recessions were noted. In the maxilla, buccal plate thickness was 0.48 to 2.14 mm. In the mandible, bone thickness was 0.2 to 1.82 mm. Root fenestrations and dehiscences were present in up to 40% of the anterior teeth. Although clinical outcomes were favorable, due to the presence of multiple posttreatment bone fenestrations and dehiscences, a revision of the treatment protocol might be considered.

Biological and clinical rationale for early implant loading.

This article questions whether early implant loading always leads to pseudointegration, as postulated by Branemark's original protocol, or whether the waiting period of 3 to 6 months can be significantly shortened in specific clinical situations and refined surgical protocols. The rationale for immediate loading of dental implants is discussed, and the evidence that immediate loading leads to implant fibrous encapsulation is reviewed. This evidence is opposed by conflicting indications that early loading induces bone growth. Micro- and macromovement are defined, and their role, as well as the importance of implant surface in the early loading protocol, is discussed. Recently published landmark human clinical trials on early implant loading also are reviewed, along with clinical, surgical, and prosthetic tips to take into consideration when planning an early implant loading case.

Use of dental implants to improve unfavorable removable partial denture design.

This study aimed to determine whether the use of a limited number of dental implants, with no rigid connection between implants and teeth and as few as possible prosthetic element requirements, is a viable solution for improving unfavorable removable partial dentures (RPD) design. Fifteen partially edentulous patients with an unfavorable number and distribution of abutment teeth were treated, each with a limited number of implants, from 1997 to 2004, resulting in an improved RPD design. Implant survival rate was 100%, and prosthetic complications were minor. All patients reported great satisfaction with the partial dentures and good chewing efficiency. The results indicate that the use of dental implants to improve unfavorable RPD design is a viable and cost-effective treatment modality.

The effect of surface processing of titanium implants on the behavior of human osteoblast-like Saos-2 cells.

BACKGROUND: The surface qualities of dental implants appear to modulate osteoblasts' growth and differentiation, affecting bone healing. During manufacturing of implants, the surface quality is affected by industrial processes. PURPOSE: To examine the effect of manufacturing procedures on the growth and differentiation of human osteoblast-like cells, Saos-2. MATERIALS AND METHODS: Saos-2 cells were cultured on titanium (Ti) disks. Cell growth was examined using the XTT assay, and cell differentiation was tested by alkaline phosphatase (ALP) activity and osteocalcin secretion. The following variables were examined: roughening of the surface by sandblasting and acid-etching, aging of the acid used for etching, fluoride modification of the surface, and the type of the packaging material. RESULTS: An inverse relationship was noted between Saos-2 growth and ALP activity on the tested surfaces. Roughening of the surface tended to decrease cell proliferation and to increase differentiation. Immersion of up to 200 cycles in acid decreased proliferation and increased differentiation. Cells grown on fluoride-modified surfaces exhibited more ALP activity as compared to the unmodified surfaces. No difference was noted between the three packaging materials tested. CONCLUSIONS: The data suggests that industrial processes may affect the behavior of osteoblast-like cells around titanium implants and should be monitored carefully by bioassays.