Patient-reported outcomes following dental implant rehabilitation according to reason for missing teeth: A survey from a Norwegian population 8 years following treatment.

AIM: The aim of this study was to assess patient-reported outcomes (PROs) 8 years after dental implant rehabilitation in a sample with tooth loss due to periodontitis (TLP) and a sample with missing teeth for other reasons (MTOR). MATERIALS AND METHODS: The Norwegian National Insurance Scheme registry of subsidized dental implant therapy was searched, and patients (n = 3083) rehabilitated with dental implants in 2014 were mailed a questionnaire. PROs were described by relative frequencies, and the TLP and MTOR subsamples were compared using chi-square test. Multiple linear regression analyses were used to investigate variables potentially predicting PROs. RESULTS: Of the respondents (n = 1299), more than 90% were partly or fully satisfied with the treatment outcome. Complications were reported by 44.2%. Patients who lost teeth due to periodontitis (n = 784) reported greater oral function improvement and better pre-treatment information, and were more likely to experience complications when compared with patients who lost teeth for other reasons (n = 515). Age, level of education, self-funded cost, pre-treatment information, history of complications and the reason for missing teeth were found to predict PROs. CONCLUSIONS: In a Norwegian population rehabilitated with dental implants in 2014, satisfaction with the treatment outcome and the aesthetic outcome was high, irrespective of the reason for missing teeth. Self-report of complications and lack of pre-treatment information were the strongest predictors of inferior patient satisfaction and also predicted inferior oral function.

Non-surgical therapy of peri-implant mucositis-Mechanical/physical approaches: A systematic review.

AIM: To study in humans with peri-implant mucositis the efficacy of (Q1) mechanical/physical instrumentation over oral hygiene instructions alone; (Q2) any single mode of mechanical/physical instrumentation over others; (Q3) combinations of mechanical/physical instrumentation over single modes; and (Q4) repetitions of mechanical/physical instrumentation over single administration. MATERIALS AND METHODS: Randomized clinical trials (RCTs) fulfilling specific inclusion criteria established to answer the four PICOS questions were included. A single search strategy encompassing the four questions was applied to four electronic databases. Two review authors independently screened the titles and abstracts, carried out full-text analysis, extracted the data from the published reports and performed the risk of bias assessment through the RoB2 tool of the Cochrane Collaboration. In case of disagreement, a third review author took the final decision. Treatment success (i.e., absence of bleeding on probing [BoP]), BoP extent and BoP severity were considered as the implant-level outcomes of critical importance for the present review. RESULTS: A total of five papers reporting on five RCTs, involving 364 participants and 383 implants, were included. Overall, treatment success rates after mechanical/physical instrumentation ranged from 30.9% to 34.5% at 3 months and from 8.3% to 16.7% at 6 months. Reduction in BoP extent was 19.4%-28.6% at 3 months, 27.2%-30.5% at 6 months and 31.8%-35.1% at 12 months. Reduction in BoP severity was 0.3-0.5 at 3 months and 0.6-0.8 at 6 months. Q2 was addressed in two RCTs, which reported no differences between glycine powder air-polishing and ultrasonic cleaning, as well as between chitosan rotating brush and titanium curettes. Q3 was addressed by three RCTs, which showed no added effect of glycine powder air-polishing over the use of ultrasonic and of diode laser over ultrasonic/curettes. No RCTs were identified that answered Q1 and Q4. CONCLUSIONS: Several mechanical/physical instrumentation procedures including curettes, ultrasonics, lasers, rotating brushes and air-polishing are documented; however, a beneficial effect over oral hygiene instructions alone or superiority over other procedures could not be demonstrated. Moreover, it remains unclear whether combinations of different procedures or their repetition over time may provide additional benefits. (CRD42022324382).

Non-surgical treatment of mild to moderate peri-implantitis with an oscillating chitosan brush or a titanium curette-12-month follow-up of a multicenter randomized clinical trial.

OBJECTIVES: To study clinical and radiographic outcomes after non-surgical treatment of peri-implantitis using either an oscillating chitosan brush (OCB) or titanium curette (TC) and to observe changes in clinical signs of inflammation after repeated treatment. METHODS: Thirty-nine patients with dental implants (n = 39) presented with radiographic bone level (RBL) of 2-4 mm, bleeding index (BI) ≥ 2, and probing pocket depth (PPD) ≥ 4 mm were randomly assigned to mechanical debridement with OCB (test) or TC (control). Treatment was performed at baseline and repeated at 3, 6, and 9 months in cases with > 1 implant site with BI ≥ 1 and PPD≥4 mm. Blinded examiners recorded PPD, BI, pus, and plaque. The radiographic bone level change between baseline and 12 months was calculated. A multistate model was used to calculate transitions of BI. RESULTS: Thirty-one patients completed the study. Both groups exhibited a significant reduction in PPD, BI, and pus at 12 months compared to baseline. Radiographic analysis showed stable mean RBL in both groups at 12 months. There was no statistically significant difference in any of the parameters between the groups. CONCLUSIONS: Within the limitations of this 12-month multicenter randomized clinical trial, non-surgical treatment of peri-implantitis with OCB or TC showed no statistically significant differences between the groups. Clinical improvements and, in some cases, disease resolution, was observed in both groups. However, persistent inflammation was a common finding which further puts emphasis on the need for further treatment.

Ulcerative colitis and periodontitis - a cross-sectional pilot study from a Norwegian cohort.

BACKGROUND: Inflammatory bowel disease, which includes ulcerative colitis (UC), is an inflammatory disorder with potential impact on periodontal disease, but evidence to date for this association is limited. The primary aim of this study was to investigate the prevalence of periodontitis according to the 2017-classification in a cohort of subjects with UC. The secondary aim was to assess a potential correlation of periodontal status with previous UC disease parameters and to assess oral health-related quality-of-life. METHOD: A cohort from a community hospital in Norway with confirmed extensive UC was comprehensively examined. Periodontal parameters, OHIP-14 and demographic variables were collected. Previous UC data including colon activity index (CAI), Mayo score and years of UC diagnosis was used to explore a potential correlation with periodontal status. RESULTS: A total of 50 out of 63 invited patients participated. According to the 2017-classification, 74% of the patients presented periodontitis. No correlation was found between periodontitis (stage, grade, bleeding on probing or probing pocket depth ≥6mm) and CAI, Mayo score, or years with UC diagnosis. CONCLUSIONS: Within the limitations of this study, the prevalence of periodontitis among patients with mild UC for more than 12 years was in line with that reported from a Norwegian general population. No correlation between periodontitis and UC disease indices or years with UC diagnosis was observed. The study suggests that the susceptibility to periodontitis may be limited in patients with well treated or mild UD who regularly attend the dental office, despite a considerable UC disease duration.

Satisfaction and preferences among patients with both implant-supported single crown and tooth-supported fixed dental prosthesis: a pilot study.

OBJECTIVE: The objective of the study was to assess patient-reported preferences and outcomes in patients rehabilitated with both an implant-supported single crown (ISC) and a tooth-supported fixed dental prosthesis (FDP). MATERIALS AND METHODS: The electronic journal system at the Faculty of Dentistry, University of Oslo, was searched to find patients presenting both an ISC and an FDP replacing no more than two teeth between abutments. Identified patients that agreed answered a questionnaire followed by a clinical examination. Descriptive statistics was calculated. RESULTS: Thirty patients were included. The mean function time was 11.8 years for FDPs and 6.6 years for ISCs. All but three patients were satisfied with both rehabilitation modalities. No patients were unsatisfied with aesthetics or function of either rehabilitation. All patients reported satisfactory function of their restorations and reported chewing without problems. The self-reported post-operative complications were few, but less than observed in the clinical examinations. CONCLUSIONS: More patients reported food impaction with their FDP as compared to their ISC. Function and aesthetics of FDPs and ISCs were rated similarly, but more patients found the ISC treatment more uncomfortable. Despite this finding, most patients would prefer to undergo ISC treatment if they were to replace another missing tooth.

Association between periodontitis stages and self-reported diseases in a Norwegian population: the HUNT study.

BACKGROUND: The relationships between periodontitis and non-communicable diseases (NCDs) have been investigated through several different case-definitions. The differences in methodology may have hindered the basis of comparison between these studies. The classification from the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions offers a unison platform that may facilitate future comparison of such research. The present study aimed to reproduce associations between periodontitis and other NCDs using the 2017 Classification, in the Trøndelag Health Study (HUNT). MATERIAL AND METHODS: The fourth HUNT-survey was carried out between 2017 and 2019. Clinical variables, blood samples and answers to questionnaires were collected from 4933 participants. Periodontal status was assessed based on the latest staging system, and its associations with NCDs were estimated by logistic regression models adjusted for potential confounders. RESULTS: Compared to no or Stage I periodontitis, participants with Stage III/IV periodontitis (radiographic bone loss exceeding 33%) were associated with cardiovascular disease, hyperglycemia in participants with diabetes and chronic obstructive pulmonary disease (COPD)/emphysema. Associations with hyperglycemia in participants with diabetes and COPD/emphysema were also observed in participants with Stage II periodontitis. The only observed association when considering never-smokers alone, was with COPD/emphysema. CONCLUSION: Periodontitis Stage II and III/IV were associated with major NCDs. Effect sizes increased with increasing periodontitis stages, which implies greater occurrence of coincident comorbidities in patients with severe periodontitis.

Non-surgical treatment of mild to moderate peri-implantitis using an oscillating chitosan brush or a titanium curette-A randomized multicentre controlled clinical trial.

OBJECTIVES: This prospective, parallel-group, examiner-blinded, multicentre, randomized, controlled clinical trial aimed to assess the efficacy of an oscillating chitosan brush (OCB) versus titanium curettes (TC) on clinical parameters in the non-surgical treatment of peri-implantitis. MATERIAL AND METHODS: In five dental specialist clinics, 39 patients with one implant with mild to moderate peri-implantitis, defined as 2-4 mm radiographic reduced bone level, bleeding index (BI) ≥ 2, and probing pocket depth (PPD) ≥ 4 mm were randomly allocated to test and control groups, receiving OCB or TC debridement, respectively. Treatment was performed at baseline and three months. PPD, BI, and Plaque index (PI) were measured at six sites per implant and recorded by five blinded examiners at baseline, one, three, and six month(s). Pus was recorded as present/not present. Changes in PPD and BI were compared between groups and analysed using multilevel partial ordinal and linear regression. RESULTS: Thirty-eight patients completed the study. Both groups showed significant reductions in PPD and BI at six months compared with baseline (p < .05). There was no statistically significant difference in PPD and BI changes between the groups. Eradication of peri-implant disease as defined was observed in 9.5% of cases in the OCB group and 5.9% in the TC group. CONCLUSIONS: Within the limitations of this six-month multicentre clinical trial, non-surgical treatment of peri-implantitis with OCB and TC showed no difference between the interventions. Eradication of disease was not predictable for any of the groups.

Implantoplasty- provoking or reducing inflammation? - a systematic scoping review.

OBJECTIVES: To evaluate clinical parameters associated with inflammation after adjunctive implantoplasty in conjunction with surgical treatment of peri-implantitis. MATERIALS AND METHODS: A systematic literature search was performed in 2 databases until 29. December 2020 to find publications that report on clinical parameters after surgical peri-implantitis treatment which included adjunctive implantoplasty. Clinical studies on implantoplasty reporting on BoP as outcome were included, but other clinical or radiographic outcomes were also considered. RESULTS: The search resulted in 18 articles that fulfilled the inclusion criteria. The results indicated improvements of BoP and clinical parameters following surgical peri-implantitis treatment with adjunctive implantoplasty. CONCLUSIONS: Within its limits, the findings of the present scoping review indicated that BoP is reduced following surgical peri-implantitis treatment with adjunctive implantoplasty, and that this improvement is in line with surgical peri-implantitis treatment without adjunctive implantoplasty.

Patient and professional use of the root coverage esthetic score (RES) and how it relates to patient satisfaction following periodontal plastic surgery.

BACKGROUND: Following periodontal plastic surgery in the treatment of recession defects, previous studies have reported that patients rate the esthetic outcomes more favorable than dental professionals. The root coverage esthetic score has been developed and suggested to serve as a comprehensive assessment instrument as it addresses several esthetic outcomes following root coverage procedures. However, no study has yet reported on patient use of this instrument. In the present study clinical, esthetic and patient-reported outcomes following periodontal plastic surgery were assessed. The primary objective was to compare the esthetic/clinical outcome as judged by the patient and by one dentist by using the root coverage esthetic score. The secondary objective was to evaluate the correlation between patient-reported outcomes, root coverage esthetic score and clinical parameters following treatment of recession defects. MATERIALS AND METHODS: Subjects that had undergone periodontal plastic surgery were invited to score the treatment outcome according to the root coverage esthetic score, which subsequently also was professionally scored by a dentist. Thereafter, the subjects answered a questionnaire on patient satisfaction. All types of surgical root coverage procedures in canine or incisor teeth were included. RESULTS: A total of 34 subjects were included, presenting 46 treated recessions. No statistically significant different score was found comparing the root coverage esthetic score by the patient and the professional. The majority of subjects was satisfied with the treatment outcome, and most would have undergone the treatment again. CONCLUSION: The root coverage esthetic score assessment can be conducted by patients and was not statistically significant different to that of the professional. Patient satisfaction is not always dependent on complete root coverage or the other clinical parameters included in the root coverage esthetic score.

Prevalence of periodontitis based on the 2017 classification in a Norwegian population: The HUNT study.

AIM: This cross-sectional study assesses the prevalence of periodontitis in a large Norwegian population, based on the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions. The prevalence of periodontitis was determined by bone loss recorded on radiographs (orthopantomogram [OPG] and bitewing [BW]) and by clinical examination. MATERIALS AND METHODS: As part of a large population health study (The HUNT Study), 7347 participants aged 19 years and older were invited to the HUNT4 Oral Health Study. Radiographic bone loss (RBL) and periodontal stage and grade were assessed in 4863 participants. RESULTS: Periodontal examination was performed in 4863 participants. RBL and clinical registrations corresponding to periodontitis as defined were observed in 72.4%. The prevalence of periodontitis increased after 40 years of age, with severe forms occurring primarily after 60 years of age. Stage I was observed in 13.8%, Stage II in 41.1%, Stage III in 15.3%, and Stage IV in 2.3% of the population. Grade A, B, and C was observed in 5.7%, 60.2%, and 6.2%, respectively. CONCLUSION: Periodontitis was frequently observed in the investigated population. The prevalence of periodontitis Stage III and Stage IV combined was observed in 17.6% of the study population.

Guided bone regeneration of chronic non-contained bone defects using a volume stable porous block TiO2 scaffold: An experimental in vivo study.

OBJECTIVES: To evaluate new lateral bone formation and lateral volume augmentation by guided bone regeneration (GBR) in chronic non-contained bone defects with the use of a non-resorbable TiO2 -block. MATERIALS AND METHODS: Three buccal bone defects were created in each hemimandible of eight beagle dogs and allowed to heal for 8 weeks before treatment by GBR. Each hemimandible was randomly allocated to 4- or 12-week healing time after GBR, and three intervention groups were assigned by block randomization: TiO2 block: TiO2 -scaffold and a collagen membrane, DBBM particles: Deproteinized bovine bone mineral (DBBM) and a collagen membrane, Empty control: Collagen membrane only. Microcomputed tomography (microCT) was used to measure the lateral bone formation and width augmentation. Histological outcomes included descriptive analysis and histomorphometric measurements. RESULTS: MicroCT analysis demonstrated increasing new bone formation from 4 to 12 weeks of healing. The greatest width of mineralized bone was seen in the empty controls, and the largest lateral volume augmentation was observed in the TiO2 block sites. The DBBM particles demonstrated more mineralized bone in the grafted area than the TiO2 blocks, but small amounts and less than the empty control sites. CONCLUSION: The TiO2 blocks rendered the largest lateral volume augmentation but also less new bone formation compared with the DBBM particles. The most new lateral bone formation outward from the bone defect margins was observed in the empty controls, indicating that the presence of either graft material leads to slow appositional bone growth.

Experimental implantoplasty outcomes correlate with fibroblast growth in vitro.

BACKGROUND: Implantoplasty is an option in peri-implantitis treatment, but little is known about the effect on the soft tissue. The aim of the study was to characterize surface roughness following experimental implantoplasty and to examine its effect on human fibroblast growth and secretion of selected proteins. METHODS: Titanium grade IV coins were mechanically treated with six different rotating bur sequences; diamond burs or carbide burs alone, or followed by either Arkansas stone bur or silicone burs. Machined and rough-surface sandblasted, acid-etched (SLA) coins were used as control. The surface topography was characterized by scanning electron microscope and profilometer. Human gingival fibroblasts from two donors were cultured on the coins to quantify the effect on cell morphology, growth, and protein secretion by confocal microscopy and multiplex immunoassay. RESULTS: All surface roughness parameters were lower for the surfaces treated with experimental implantoplasty than for the SLA surface, and the sequence of carbide burs followed by silicone burs rendered the least rough surface of the test groups. The implantoplasty procedures changed the elemental composition of the titanium surface. High surface roughness showed a weak to moderate negative correlation to fibroblast growth, but induced a higher secretion of VEGF, IL-6 and MCP-3 to the cell medium compared to the least rough surfaces of the test groups. At day 30 fibronectin levels were higher in the SLA group. CONCLUSIONS: The surface roughness following implantoplasty demonstrated a weak to moderate negative correlation with the growth of fibroblasts. The addition of Arkansas stone and silicon burs to the experimental implantoplasty bur protocol rendered an initial increase in fibroblast growth. Implantoplasty altered the elemental composition of the titanium surface, and had an effect on the fibroblast cytokine secretion and fibronectin levels.

TiO2 scaffolds in peri-implant dehiscence defects: an experimental pilot study.

OBJECTIVES: The primary objective was to assess osseointegration of implants with dehiscence defects grafted with a TiO2 scaffold. The secondary objective was to assess the performance of the scaffold in terms of mechanical stability and bone fill. MATERIAL AND METHODS: Five minipigs had the mandibular premolars extracted. After healing, two dental implants (SLActive® , Institut Straumann AG, Basel, Switzerland) with associated semi-cylindrical dehiscence defects (Ø = 6 mm, height = 10 mm) were installed in each quadrant. The defects were grafted with test scaffolds (n = 10) or control autologous bone blocks (n = 10). After 3 months submerged healing, the pigs were euthanized and the sites analysed by microcomputed tomography and histology. RESULTS: Four minipigs were available for second stage surgery; (n = 9) experimental and (n = 7) control sites. The mean bone-to-implant contact on the defect side was 82% (±10%) and 79% (±11%) in the test and control groups respectively. The mean level of first bone-to-implant contact was more coronal on the defect side in the test group 3.2 mm (±0.4 mm) than in the control group 3.6 mm (±1.1 mm). The defect area occupied by bone within the extent of the scaffold varied, but averaged 37% (±14.6%) whereas the material itself occupied 7.4% (±3.5%). CONCLUSIONS: Within the limitations of the study, the results suggest that the novel synthetic scaffold material perform similar to the autologous bone block control with respect to implant osseointegration. The mechanical properties of the scaffold appeared sufficient to withstand clinical load in the present experimental model.

Osseointegration of dental implants in extraction sockets preserved with porous titanium granules - an experimental study.

OBJECTIVES: This study investigated osseointegration of dental implants inserted in healed extraction sockets preserved with porous titanium granules (PTG). MATERIAL AND METHODS: Three adult female minipigs (Gøttingen minipig; Ellegaard A/S, Dalmose, Denmark) had the mandibular teeth P2, P3 and P4 extracted. The extraction sockets were preserved with metallic PTG (Tigran PTG; Tigran Technologies AB, Malmö, Sweden) n = 12, heat oxidized white porous titanium granules (WPTG) (Tigran PTG White) n = 12 or left empty (sham) n = 6. All sites were covered with collagen membranes (Bio-Gide; Geistlich Pharma, Wolhausen, Switzerland) and allowed 11 weeks of healing before implants (Straumann Bone Level; Straumann, Basel, Switzerland) were inserted. The temperature was measured during preparation of the osteotomies. Resonance frequency analysis (RFA, Osstell; Osstell AB, Gothenburg, Sweden) was performed at implant insertion and at termination. After 6 weeks of submerged implant healing, the pigs were euthanized and jaw segments were excised for microCT and histological analyses. RESULTS: In the temperature and RFA analyses no significant differences were recorded between the test groups. The microCT analysis demonstrated an average bone volume of 61.7% for the PTG group compared to 50.3% for the WPTG group (P = 0.03) and 57.1% for the sham group. Histomorphometry demonstrated an average bone-to-implant contact of 68.2% for the PTG group compared to 36.6% for the WPTG group and 60.9% for the sham group (n.s). Eight out of ten implants demonstrated apical osseous defects in the WPTG group, but similar defects were observed in all groups. CONCLUSIONS: PTG preserved extraction sockets demonstrate a similar outcome as the sham control group for all analyses suggesting that this material potentially can be used for extraction socket preservation prior to implant installment. Apical osseous defects were however observed in all groups including the sham group, and a single cause could not be determined.

Immunohistochemical comparison of lateral bone augmentation using a synthetic TiO2 block or a xenogeneic graft in chronic alveolar defects.

OBJECTIVES: To evaluate osteogenic markers and alveolar ridge profile changes in guided bone regeneration (GBR) of chronic noncontained bone defects using a nonresorbable TiO2 block. MATERIALS AND METHODS: Three buccal bone defects were created in each hemimandible of eight beagle dogs and allowed to heal for 8 weeks before GBR. Treatment was assigned by block randomization: TiO2 block: TiO2 -scaffold and a collagen membrane, DBBM particulates: Deproteinized bovine bone mineral (DBBM) and a collagen membrane, Empty control: Only collagen membrane. Bone regeneration was assessed on two different healing timepoints: early (4 weeks) and late healing (12 weeks) using several immunohistochemistry markers including alpha-smooth muscle actin (α-SMA), osteopontin, osteocalcin, tartrate-resistant acid phosphatase, and collagen type I. Histomorphometry was performed on Movat Pentachrome-stained and Von Kossa/Van Gieson-stained sections. Stereolithographic (STL) models were used to compare alveolar profile changes. RESULTS: The percentage of α-SMA and osteopontin increased in TiO2 group after 12 weeks of healing at the bone-scaffold interface, while collagen type I increased in the empty control group. In the defect area, α-SMA decreased in the empty control group, while collagen type I increased in the DBBM group. All groups maintained alveolar profile from 4 to 12 weeks, but TiO2 group demonstrated the widest soft tissue contour profile. CONCLUSIONS: The present findings suggested contact osteogenesis when GBR is performed with a TiO2 block or DBBM particulates. The increase in osteopontin indicated a potential for bone formation beyond 12 weeks. The alveolar profile data indicated a sustained lateral increase in lateral bone augmentation using a TiO2 block and a collagen membrane, as compared with DBBM and a collagen membrane or a collagen membrane alone.

Impact of simultaneous placement of implant and block bone graft substitute: an in vivo peri-implant defect model.

BACKGROUND: Insufficient bone volume around an implant is a common obstacle when dental implant treatment is considered. Limited vertical or horizontal bone dimensions may lead to exposed implant threads following placement or a gap between the bone and implant. This is often addressed by bone augmentation procedures prior to or at the time of implant placement. This study evaluated bone healing when a synthetic TiO2 block scaffold was placed in circumferential peri-implant defects with buccal fenestrations. METHODS: The mandibular premolars were extracted and the alveolar bone left to heal for 4 weeks prior to implant placement in six minipigs. Two cylindrical defects were created in each hemi-mandible and were subsequent to implant placement allocated to treatment with either TiO2 scaffold or sham in a split mouth design. After 12 weeks of healing time, the samples were harvested. Microcomputed tomography (MicroCT) was used to investigate defect fill and integrity of the block scaffold. Distances from implant to bone in vertical and horizontal directions, percentage of bone to implant contact and defect fill were analysed by histology. RESULTS: MicroCT analysis demonstrated no differences between the groups for defect fill. Three of twelve scaffolds were partly fractured. At the buccal sites, histomorphometric analysis demonstrated higher bone fraction, higher percentage bone to implant contact and shorter distance from implant top to bone 0.5 mm lateral to implant surface in sham group as compared to the TiO2 group. CONCLUSIONS: This study demonstrated less bone formation with the use of TiO2 scaffold block in combination with implant placement in cylindrical defects with buccal bone fenestrations, as compared to sham sites.

Titanium Granules for Augmentation of the Maxillary Sinus - A Multicenter Study.

BACKGROUND: Biomaterials are commonly used to augment the maxillary sinus floor prior to or in conjunction with dental implant installation. Recently, porous titanium granules (PTGs) have been used in oral implant surgery to stabilize implants and function as an osteoconductive matrix. PURPOSE: To evaluate if PTGs can be safely used in a larger population of patients, treated by different surgeons, when sinus floor augmentation was required in conjunction with implant installation. The primary endpoint was 12-month survival rate of the dental implants. Biopsies for histology were taken from the augmented area. MATERIALS AND METHODS: At five centers, 40 subjects with uni or bilateral posterior edentulism and atrophy of the posterior maxilla (3-6 mm) were enrolled. In a single-stage procedure, PTG and one to three dental implants were installed in each quadrant. In total, 70 implants were included in the study. RESULTS: One immobile implant was removed. The mean marginal bone loss was 0.5 mm and 0.8 mm, on the mesial and distal side, respectively. Histologically, all biopsies demonstrated bone ingrowth. CONCLUSIONS: The results suggest that PTG can be safely and effectively used as augmentation material in the sinus floor when used with dental implants in a one-stage procedure.

Alginate hydrogel enriched with enamel matrix derivative to target osteogenic cell differentiation in TiO2 scaffolds.

The purpose of bone tissue engineering is to employ scaffolds, cells, and growth factors to facilitate healing of bone defects. The aim of this study was to assess the viability and osteogenic differentiation of primary human osteoblasts and adipose tissue-derived mesenchymal stem cells from various donors on titanium dioxide (TiO2) scaffolds coated with an alginate hydrogel enriched with enamel matrix derivative. Cells were harvested for quantitative reverse transcription polymerase chain reaction on days 14 and 21, and medium was collected on days 2, 14, and 21 for protein analyses. Neither coating with alginate hydrogel nor alginate hydrogel enriched with enamel matrix derivative induced a cytotoxic response. Enamel matrix derivative-enriched alginate hydrogel significantly increased the expression of osteoblast markers COL1A1, TNFRSF11B, and BGLAP and secretion of osteopontin in human osteoblasts, whereas osteogenic differentiation of human adipose tissue-derived mesenchymal stem cells seemed unaffected by enamel matrix derivative. The alginate hydrogel coating procedure may have potential for local delivery of enamel matrix derivative and other stimulatory factors for use in bone tissue engineering.

Porous ceramic titanium dioxide scaffolds promote bone formation in rabbit peri-implant cortical defect model.

Titanium oxide (TiO2) scaffolds have previously been reported to exhibit very low mechanical strength. However, we have been able to produce a scaffold that features a high interconnectivity, a porosity of 91% and a compressive strength above 1.2 MPa. This study analyzed the in vivo performance of the porous TiO2 scaffolds in a peri-implant cortical defect model in the rabbit. After 8 weeks of healing, morphological microcomputed tomography analyses of the defects treated with the TiO2 scaffolds had significantly higher bone volume, bone surface and bone surface-to-volume ratio when compared to sham, both in the cortical and bone marrow compartment. No adverse effects, i.e. tissue necrosis or inflammation as measured by lactate dehydrogenase activity and real-time reverse transcription polymerase chain reaction analysis, were observed. Moreover, the scaffold did not hinder bone growth onto the adjacent cortical titanium implant. Histology clearly demonstrated new bone formation in the cortical sections of the defects and the presence of newly formed bone in close proximity to the scaffold surface and the surface of the adjacent Ti implant. Bone-to-material contact between the newly formed bone and the scaffold was observed in the histological sections. Islets of new bone were also present in the marrow compartment albeit in small amounts. In conclusion, the present investigation demonstrates that TiO2 scaffolds osseointegrate well and are a suitable scaffold for peri-implant bone healing and growth.

Maxillary sinus augmentation with porous titanium granules: a microcomputed tomography and histologic evaluation of human biopsy specimens.

PURPOSE: The aim of this study was to assess bone ingrowth into porous titanium granules used for maxillary sinus augmentation. MATERIALS AND METHODS: Eighteen biopsy specimens from 17 patients participating in a clinical trial on sinus augmentation using porous titanium granules (PTG) were received in the laboratory. The specimens (trephine cores of 4.5 mm) were obtained 6 months after PTG placement. After being embedded in methacrylate, the samples were scanned in a microcomputed tomography (micro-CT) scanner. Specimens were then cut along the long axis and central slices were ground to 70 µm before staining with hematoxylin and eosin. RESULTS: The micro-CT analysis demonstrated an average bone fill of 19% (standard deviation [SD] 5.8%), whereas the graft material occupied 22.7% (SD 4.7%). The volume of newly formed bone decreased with the distance from the residual bone of the sinus floor. Two-dimensional histomorphometric analysis demonstrated a mean area of new bone of 16.1% (SD 9.4%). The PTG alone occupied 25.9% of the total mean area (SD 6.1%). The newly formed bone consisted mainly of woven bone growing in close contact with the granules and bridging the intergranular space. The remaining area was occupied predominantly by nonmineralized connective tissue. There were no signs of inflammation in any of the biopsy specimens. CONCLUSIONS: After 6 months, new bone had formed at a similar rate and quality as has been reported for other well-recognized bone graft substitutes. The new bone formed in close contact with the PTG, suggesting that the material is osteoconductive.