Survival rates of ultra-short (<6 mm) compared with short locking-taper implants supporting single crowns in posterior areas: A 5-year retrospective study.

BACKGROUND: Short and ultra-short implants represent a predictable treatment, in terms of implant survival, with patients presenting insufficient available bone volumes. Moreover, single crown restorations represent a gold standard in terms of oral hygiene. PURPOSE: The aim of this retrospective study was to evaluate implant survival, marginal bone loss, and peri-implant complications in 333 locking-taper short and ultra-short implants. MATERIALS AND METHODS: Implants were placed in the maxillary and mandibular posterior regions of 142 patients. Clinical and radiographic examinations were performed at 5-year recall appointments. RESULTS: All implants placed consisted of 8.0-, 6.0-, and 5.0-mm length, 38.14%, 34.53%, and 27.33%, respectively. Three hundred thirty-two implants (one early failure) were rehabilitated with single crowns in 141 patients. In 45.48% of the implants the crown-to-implant ratio was ≥2, with a mean value of 1.94. Overall implant-based survival after 5 years of follow-up was 96.10%: 96.85%, 95.65%, and 95.60% for 8.0-, 6.0-, and 5.0-mm length implants, respectively (p = 0.82). Overall patient-based survival was 91.55%. Regarding crestal bone level variations, average crestal bone loss and apical shift of the "first bone-to-implant contact point" position were 0.69 and 0.01 mm, respectively. Setting the threshold for excessive bone loss at 1 mm, during the time interval from loading to follow-up, 28 implants experienced loss of supporting bone greater than 1 mm: 19 of them (67.85%) were surgically treated with a codified surgical regenerative protocol. After 60 months, a peri-implantitis prevalence of 5.94% was reported, with an overall implant success of 94.06%: 95.93%, 92.73%, and 93.10% for 8.0-, 6.0-, and 5.0-mm length implants, respectively (p = 0.55). CONCLUSION: Long-term outcomes suggest that short and ultra-short locking-taper implants can be successfully restored with single crowns in the posterior area of the maxilla and mandible.

Effects of oral function on pupil response: a new view on bruxism pathophysiology.

BACKGROUND: There is increasing evidence of the influence of the oropharyngeal stimulations on the autonomic nervous system and an easy approach to evaluate the balance between parasympathetic and sympathetic system is the measurement of the pupil diameter. The aim of this analytic observational study is to define the effects of clenching and swallowing on pupil diameter, and how an oral appliance can affect the outcome of these tasks, to establish their influence on the sympathetic-parasympathetic balance. METHODS: We measured the pupil diameter in 30 healthy subjects during clenching and swallowing, both with and without oral appliance. We compared the results with the mandibular rest position. The respective positions with and without oral appliance were also compared. RESULTS: Pupillometry showed a mydriatic effect of swallowing (rest 6.94 mm, swallowing 7.26 mm, P=0.04) and oral appliance, more relevant in scotopic conditions. On the contrary, clenching seemed to enhance miosis, especially in intense brightness condition (rest 3.95 mm, clenching 3.83 mm, P=0.02). CONCLUSIONS: Swallowing and oral appliance facilitate the sympathetic system, while clenching activates the parasympathetic branch. We argue that probably the locus coeruleus is the main hub. These results could have practical implications in bruxism physiology, because it could be an attempt to counteract the activation of the sympathetic system.

Fresh-frozen homologous bone in sinus lifting: histological and radiological analysis.

BACKGROUND: The aim of this study was to evaluate radiological and histological characteristics of fresh-frozen homologous bone as grafting material for maxillary sinus floor augmentation. Radiological, histological and clinical evaluations were made. METHODS: Twenty-three patients with a 2 mm to 6 mm alveolar ridge height in the posterior maxilla have been enrolled. Unilateral or bilateral sinus floor augmentations were performed with fresh frozen morcelized homologous bone. Together with implant placement, 7 months after surgery, a bone core was harvested for histological analysis. Radiological measurements were obtained by superimposition of CT scans carried out at the surgery time and six months later. A total of 93 implants were positioned. RESULTS: A mean (±SD) increase in mineralized tissue height of 10.74±2.82 mm was noticed by comparing the CT scans. Histological analysis revealed the presence of newly formed bone in the grafted sites. The follow up period after the prosthetic load ranged from 8 to 31 months. One implant failure occurred. CONCLUSIONS: Fresh frozen homologous bone seems to have a good healing pattern and to be a successful and steady grafting material for the treatment of maxillary ridge atrophy. It might be considered a valid alternative to autologous bone in sinus floor augmentation procedures.

Implant rehabilitation of the edentulous jaws: Does tilting of posterior implants at an angle greater than 45° affect bone resorption and implant success?: A retrospective study.

PURPOSE: This study aimed to (1) investigate the success of posterior implants tilted >45° when 4 immediately loaded implants were used to support full-arch prostheses, eliminating any distal cantilever and (2) examine the effect on marginal bone loss (MBL) of different combinations of anterior multi-unit abutment (MUA) angles and posterior implant tilting angles. MATERIALS AND METHODS: Records of patients rehabilitated according to the Columbus Bridge Protocol were analyzed. Peri-implant bone levels (PBLs) and MBL were measured for each implant. The influence of posterior implant tilting angle on PBL, MBL, and implant and prosthetic success rate was investigated. The impact on the same endpoints of different anterior MUA angles, and different combinations of anterior MUA and tilted posterior implant angles was also examined. RESULTS: Records of 41 patients were analyzed, for a total of 46 complete rehabilitations, and 142 implants (52 anterior, 63 posterior tilted ≤45° [group 1], and 27 posterior tilted >45° [group 2]). No implants were lost during the follow-up (25.9 months), and no prosthetic complications were reported. Success rate for posterior implants was 100% in group 1 and 96.3% in group 2. Mean MBL differed significantly between the 2 groups (0.45 mm in group 1, 0.66 in group 2 [P = .04]), but not when the analysis was limited to implants in the same jaw. Implant tilting angle did not correlate with MBL and the MUA angle had no effect on bone resorption around posterior implants, neither in the sample as a whole nor in individual patients. CONCLUSIONS: Posterior implants tilted >45° to eliminate distal cantilever may be as safe as those tilted less in severely atrophic jaws rehabilitated with immediately loaded, full-arch prostheses supported on 4 implants. Further prospective studies on larger samples of patients and implants and with longer follow-up are needed to confirm these findings.

The facial grid analysis for filler injection: a cohort study of 300 patients.

BACKGROUND: Filler injection is widely used for facial rejuvenation. Global skin rejuvenation requires the precise sequential injections of different areas, but a standardized and reproducible method is lacking. The purpose of the study was to develop a new method for a precise measurement of the degree of facial defect before and after full-face rejuvenation with injectable fillers, so called facial filler (FAFI) grid. METHODS: Three hundreds patients were included. There were 76 males and 224 females with a median age of 30.5 years. A grid of horizontal and vertical lines was drawn on the patients' face with a rigid meter and a surgical pen to identify some precise areas for sequential filler injections. The grid was also used to measure the defects and the corrections obtained. Three different formulations of hyaluronic acid were used for treating specific facial areas. RESULTS: Correction was judged adequate in 77% and 90% of cases by the physician and patients, respectively. Prevalence of adverse events was 8.8%, with mostly mild, with resolution in few weeks. CONCLUSIONS: FAFI grid proved to be helpful in guiding sequential injections for total facial rejuvenation.

Peripheral ameloblastoma of the upper gingiva: Report of a case and literature review.

According to the 2005 histological classification of odontogenic neoplasms by the World Health Organization, ameloblastoma is a benign, locally invasive epithelial odontogenic tumor of putative enamel organ origin. There are four distinct subgroups in which this neoplasm can be gathered: the solid/multicystic type, the unicystic type, the desmoplastic and the peripheral type. Peripheral ameloblastoma is believed to be the rarest subgroup, making up for 2 to 10% of all ameloblastomas. From its first description by Kuru in 1911 to date, less than 200 cases of PA have been described in literature. PAs commonly affect the mandible, in the maxilla the most common location is the soft palatal tissue of the tuberosity area. The present report discusses a rare case of PA aroused in the gingiva of upper jaw in a 64-year-old woman. The treatment of the lesion and its immunohistochemical phenotype are described. A review of the literature is also performed, focusing on the epidemiological and pathological aspects of the lesions and their implications on the therapy. Key words:Peripheral ameloblastoma, upper gingiva, ameloblastoma.

Influence of crown-implant ratio on implant success rates and crestal bone levels: a 36-month follow-up prospective study.

OBJECTIVES: The aim of this prospective study was to determine how the crown-implant ratio (C/I ratio) influences crestal bone loss and implant success rates after a 3-year follow-up, using implants with a sintered porous surface (SPS). MATERIALS AND METHODS: On the basis of preestablished inclusion and exclusion criteria, 151 of a cohort of 160 patients with single or partial edentulism were selected as eligible for the study. The 151 patients were treated consecutively from 2005 to 2007 using 280 SPS implants, which were restored with a single crown or a partial fixed denture. The data collection included both clinical and anatomical C/I ratios; other implant prosthetic factors were also recorded. Implants were divided into three groups according to the C/I ratio. Clinical and radiographic examinations were scheduled over a 36-month follow-up of functional loading according to a well-established protocol generally applied to determine implant success rates and crestal bone levels. Statistical analysis was used to determine any significant differences or correlations (P = 0.05). RESULTS: A total of 259 SPS implants in 136 patients were followed up for 36 months. According to the success criteria, the overall implant-based success rate was 98.1%, and the mean peri-implant bone loss (PBL) was 0.48 ± 0.29 mm. Statistical analysis revealed significant correlation between implant success rate and C/I ratio (P < 0.05) and between PBL and C/I ratio (P < 0.05). The critical threshold value of the anatomical and clinical C/I ratio for avoiding excessive bone loss or implant failure was 3.10 and 3.40. CONCLUSION: This prospective cohort study revealed that SPS implants offer a predictable solution for implant prosthetic rehabilitation in patients with edentulism characterized by different alveolar bone atrophy. From the biomechanical point of view, the C/I ratio would appear to be the main parameter capable of influencing implant success and crestal bone loss. Consequently, it is important not to exceed the threshold values in order to avoid excessive stress at the bone-implant interface capable of resulting in excessive crestal bone loss or implant failure.

Sliding genioplasty using fresh-frozen bone allografts.

OBJECTIVE To present our experience in the use of fresh-frozen human bone allograft as an interpositional grafting material for sliding genioplasty to correct chin deformities. METHODS Ten patients underwent sliding genioplasty using morcellized and corticospongious fresh-frozen human bone. Four patients underwent orthognathic surgery associated with genioplasty. Six patient underwent genioplasty associated with rhinoplasty. Panorex, lateral, and frontal cephalogram and computed tomographic scans have been performed for each case preoperatively and 12 months after surgery. One patient subsequently asked for plate removal, and with his consent, a bone biopsy specimen was obtained during the operation. RESULTS Stable aesthetic and functional results were observed in all cases. No infections occurred, and no bone resorption has been clinically or radiologically observed. CONCLUSION The use of fresh-frozen bone allograft reduces patient morbidity and operative time, providing a stable and excellent aesthetic result.

Two techniques for the preparation of cell-scaffold constructs suitable for sinus augmentation: steps into clinical application.

The objective of this clinical trial was the analysis of 2 methods for engineering of autologous bone grafts for maxillary sinus augmentation with secondary implant placement. Group 1 (8 patients, 12 sinuses): cells of mandibular periosteum were cultured in a good manufacturing practice laboratory (2 weeks) with autologous serum and then transferred onto a collagen matrix. After another week, these composites were transplanted into the sinuses. In group 2A (2 patients, 3 sinuses), cells of maxillary bone were cultivated with autologous serum for 2 weeks, seeded onto natural bone mineral (NBM, diameter [Ø] = 8 mm) blocks, and cultivated for another 1.5 months. These composites were transplanted into the sinuses. Group 2B (control, 3 patients, 5 sinuses) received NBM blocks alone. In the course of implant placement 6 (group 1) and 8 (group 2) months later, core biopsy were taken. Clinical follow-up period was 1 to 2.5 years in group 1 and approximately 7 years in groups 2A and 2B. New vital bone was found in all cases at median densities of 38% (n = 12) in group 1, 32% in group 2A (n = 3), and 25% in group 2B (n = 5). Differences between group 1 and 2B as well as 2A and 2B were statistically significant ( p = 0.025). No adverse effects were seen. All methods described were capable of creating new bone tissue with sufficient stability for successful implant placement.