ABSTRACT
Objective:To investigate the anatomical characteristics of human hepatic anterior fissure vein.Methods:The retrospective and descriptive study was used. A total of 22 adult cadaver specimens were collected from the Department of Human Anatomy of Harbin Medical University from March 2018 to March 2021. There were 15 males and 7 females, aged 45(range, 18?75)years. Observation indicators: (1) recognition rate of hepatic anterior fissure vein and the location of hepatic anterior fissure vein merging into hepatic vein; (2) length of hepatic anterior fissure vein and the opening diameter of hepatic anterior fissure vein merging into hepatic vein; (3) location of hepatic anterior fissure vein and the ventral hepatic vein of segment Ⅷ of liver (V8v) as well as V8v condition; (4) relationship among hepatic anterior fissure vein, anterior ventral portal vein and anterior dorsal portal vein. Measurement data with normal distribution were represented as Mean± SD, and t test was used for comparison between groups. Measurement data with skewed distribution were represented as M(range), and count data were expressed as absolute numbers or percentages. Results:(1) Recognition rate of hepatic anterior fissure vein and the location of hepatic anterior fissure vein merging into hepatic vein. The recognition rate of hepatic anterior fissure vein of 22 liver samples was 90.9% (20/22). There were 9.1%(2/22) of liver samples without hepatic anterior fissure vein. The proportions of hepatic anterior fissure vein merging into proximal middle hepatic vein and proximal right hepatic vein were 19/20 and 1/20, respectively. There was no liver sample with hepatic anterior fissure vein merging into distal middle hepatic vein and distal right hepatic vein. (2) Length of hepatic anterior fissure vein and the opening diameter of hepatic anterior fissure vein merging into hepatic vein. In the 20 liver samples with hepatic anterior fissure vein, the length of hepatic anterior fissure vein was (6.41±1.26)cm, and the opening diameter of hepatic anterior fissure vein merging into hepatic vein was (0.38±0.10)cm. (3) Location of anterior fissure vein and the V8v and V8v condition. In the 22 liver samples, there were 25 V8v branches merging into the proximal middle hepatic vein, with the V8v length as (3.83±0.36)cm and the V8v diameter as (0.16±0.08)cm. In the 17 liver samples with both hepatic anterior fissure vein and V8v, the proportion of V8v merging into hepatic anterior fissure vein and then into middle hepatic vein was 14/17, the proportion of hepatic anterior fissure vein and V8v merging into middle hepatic vein separately was 3/17, and there was no liver sample with hepatic anterior fissure vein merging into right hepatic vein and V8v merging into middle hepatic vein. (4) Relationship among hepatic anterior fissure vein, anterior ventral portal vein and anterior dorsal portal vein. Of the 20 liver samples with hepatic anterior fissure vein, the hepatic anterior fissure vein of 16 liver samples could be used as the demarcation mark of anterior ventral segment and anterior dorsal segment of hepatic right anterior region. The distance between the hepatic anterior fissure vein and anterior ventral portal vein was (1.40±0.43)cm, and that between the hepatic anterior fissure vein and anterior dorsal portal vein was (1.46±0.63)cm, showing no significant difference between them ( t=1.00, P>0.05). Conclusion:The hepatic anterior fissure vein exists in most normal adult livers, and it mostly merges into proximal middle hepatic vein. The hepatic anterior fissure vein can be identified by the condition of V8v. The hepatic anterior fissure vein can be used as the demarcation mark of anterior ventral segment and anterior dorsal segment of hepatic right anterior region.
ABSTRACT
Objective@# To explore the early failure of narrow-diameter implants (NDIs) and to provide a reference for clinical implant restoration.@*Methods@# From April 2017 to April 2020, data from a total of 725 patients (with 1 001 NDIs) who accepted implant restoration due to dentition defects were collected from the department of dental implantology in a stomatological hospital; 353 males and 372 females were included. The early failure rate of 1 001 NDIs was retrospectively analyzed. Univariate generalized estimated equation (GEE) and multivariate GEE were used to explore risk factors, including age, sex, implant location, materials, surface modification, length, bone augmentation and healing procedure, associated with early failure of NDIs.@*Results@#There were 34 cases of early failure among 725 patients, including 38 NDIs. The early failure rate of NDIs was 4.69% at the patient level and 3.80% at the implant level. There was no significant difference in the early failure rate of NDIs among different age groups, sexes, implant materials, surface modifications, lengths, and healing procedures (P>0.05). Univariate analysis showed that there was a significant difference between the early failure rate of NDIs in the anterior maxilla group (2.16%) and the anterior mandible group (8.64%) at the implant level (P<0.001). However, there was no significant difference in the early failure rate between the anterior maxilla group and the posterior group (3.35%) (P>0.05). In addition, in the anterior region, the early failure rate of NDIs in the group with simultaneous bone augmentation was significantly lower than that of the group without bone augmentation (P<0.05). However, multivariate GEE analysis showed that the early failure rate of NDIs was only significantly positively correlated with implants in the mandibular anterior region (P<0.01). @*Conclusion @#The overall early survival rate of Straumann 3.3 mm NDIs is greater than 95%. The early failure of NDIs in the anterior mandible region is much higher than that in the anterior maxilla region and posterior region.
ABSTRACT
Objective@#To study the postoperative soft and hard tissue changes and aesthetic effect of immediate implantation and provisionalization (IIPP) combined with guided bone regeneration (GBR) for a single anterior maxillary tooth with a thin facial bone phenotype.@*Methods @# A total of 34 patients with thin facial bone (<1 mm) were categorized into two groups: a flapped GBR group and a flapless group. Tooth extraction and IIPP were conducted at the sites in both groups. Implant survival rates, dimensional changes in soft and hard tissues during the six- and twelve-month follow-ups, the pink esthetic score (PES) and patient satisfaction scores at the twelve-month follow-up were measured.@*Results @#The implant survival rates were 100% in both groups, and no complications occurred during the 12 months after surgery. The facial bone thickness remained over 2 mm on all measured sides, and the height of the facial bone crest remained at 1.39 mm at the 12-month follow-up in the flapped GBR group, while the facial bone thickness remained less than 2 mm on all measured sides, and the height of the facial bone crest remained at 1.03 mm at the 12-month follow-up in the flapless group. The absorption of facial bone at all measured sides in the flapped GBR group was greater than that in the flapless group (P<0.05). There was no significant difference between the two groups in the dimensional changes of labial soft tissues during the six- and twelve-month follow-ups (P>0.05). The mean PES scores were 10.29 ± 2.34 for the flap GBR group and 10.12±1.78 for the flapless group (P = 0.807). The mean patient satisfaction scores were 8.65 ± 1.27 in the flapped GBR group and 8.76 ± 1.25 in the flapless group, and the patients in both of the groups were satisfied with the esthetic outcomes (P = 0.787). @*Conclusion @#IIPP combined with GBR might be a prospective treatment strategy for a single anterior maxillary tooth with a thin facial bone phenotype, but the esthetic risks should never be ignored.
ABSTRACT
Objective @# To investigate the effect of immediate and delayed implant placement on dimensional changes in hard and soft tissues as well as esthetic outcomes. @*Methods @# A total of 40 maxillary single anterior teeth with a dehiscence defect on the labial bone (≤4 mm) were categorized into two groups according to the timing of implant placement: immediate implant placement (n = 20) or delayed implant placement (n = 20). Guided bone regeneration (GBR) was conducted at the sites using a flap approach, and the implants were given immediate provisionalization. Implant survival rates, dimensional changes in hard and soft tissues during the six- and twelve-month follow-ups, and pink esthetic scores (PESs) were measured. @*Results @# The implant survival rates in both groups were 100%, and no complications occurred during the follow-up time. There was no significant difference between the two groups at the measurement sites in the dimensional change of hard and soft tissues during the six- and twelve-month follow-ups. The largest resorption was observed at the implant neck, with a loss of (1.29 ± 0.71) mm in the immediate implant placement group and (1.43 ± 0.19) mm in the delayed implant placement group. The mean PES scores were (10.95 ± 1.51) for the immediate implant placement group and (11.05 ± 1.23) for the delayed implant placement group. @*Conclusion@# Immediate implantation or delayed implantation combined with GBR and immediate provisionalization might both be a prospective treatment strategy for a maxillary single anterior tooth with a dehiscence defect on the labial bone.
ABSTRACT
@#The method of placing an implant immediately into the fresh extraction socket at the same time as tooth extraction has the advantages of reducing the number of operations and the overall treatment time, making full use of the existing bone mass, and resulting in ideal aesthetic effects. However, immediate implant placement also has its own inherent shortcomings. Due to the existence of the extraction socket, it is difficult to close the wound; because the size of the implant does not match the size of the extraction socket, it is difficult to achieve good initial stability, and there is a risk of soft tissue recession. This article reviews the success rate, indications and expansion of immediate implant placement, surgical requirements, complications and the prevention and treatment of anterior teeth in the aesthetic area. A literature review showed that the 5-year success rate of immediate implant placement was over 95%. The indications included intact socket walls, a facial bone wall at least 1 mm in thickness, the presence of thick, soft tissue, the absence of acute infection at the site, and the availability of bone apically and lingually to the socket to provide primary stability. In addition, in recent years, with the improvement of surgical implantation technology and the improvement of bone substitute material performance, immediate implant placement can be used as one of the conventional methods for oral implantation treatment, and its indications have shown a trend toward expansion. Immediate implant placement also has complications, including poor placement of implants and gingival receding that results in poor aesthetic outcomes. In addition, immediate restoration and conventional loading protocols after immediate implant appear to have similar outcomes and result in better aesthetic effects. However, the long-term stability and patient satisfaction after immediate implant placement in terms of soft tissue aesthetics require more research.
ABSTRACT
Objective:To assess the clinical efficacy of two different diameter Osstem MS one-stage implant restoration of small edentu-lous space in the mandibular anterior region.Methods:85 patients were treated by Osstem MS one-stage implant with the diameter of 2.5 mm(n =66)and 3.0 mm(n =66)respectively for the restoration of small edentulous space in mandibular anterior region.The mesi-al and distal marginal bone level and soft tissue were statistically analyzed after 1 2 and 24 months of functional load.The implant survival rate was evaluated according to Wheeler's survival criteria.Results:The survival rate of the implants was 1 00%.The mean changes in marginal bone level(mm)on the mesial side of 2.5 mm and 3.0 mm diameter implants were 0.275 ±0.638 and 0.098 ±0.31 9,distal aspects were 0.360 ±0.588 and 0.1 09 ±0.323 after 1 2 months of functional load;while 0.299 ±0.672 and 0.099 ±0.31 8,0.381 ± 0.581 and 0.1 07 ±0.31 9 after 24 months of functional load.The mesial and distal marginal bone loss of 2.5 mm diameter implant was greater than that of 3.0 mm after 1 2 and 24 months of functional load(P 0.05).No relevant complication of peri-implant soft tissue was shown.Conclusion:Favorable clinical effects including function and aesthetics can be achieved by Osstem MS one-stage implant with the diameter of 2.5 mm or 3.0 mm for the restoration of small edentulous space in the mandibular anterior region,however,the mar-ginal bone loss was greater around 2.5 mm diameter implant.
ABSTRACT
Objective To evaluate the clinical and aesthetic results of guide bone regeneration(GBR)with acellular dermal matrix and implant placement in the maxillary anterior region.Methods 29 cases in the maxillary anterior region were selected carefully, GBR with acellular dermal matrix were processed and the implants were placed immediately.Impressions were taken after soft tis-sue development with provisional implant restorations and the definitive restorations were finished.The follow-up time was 3 to 9 months.The evaluated indexes involved marginal bone level at mesial and distal aspects of the implants,the interproximal papilla in-dex score of Jemt′s classification and the level of the labial soft-tissue margin.Results 29 cases were good bone integration,implant without mobility.Hard and soft tissue around implants in good condition,aesthetic effect was satisfied.Conclusion Using acellular dermal matrix to come forward to tooth GBR and implanted implant during this period,can obtain satisfactory clinical effect in the short term.
ABSTRACT
The main aim of dental implant placement on the anterior region is to recover the function and esthetics. Therefore, this study examined the angulation between the long axis of the anterior teeth and the alveolar process, and thickness of the alveolar bone on the anterior region. Twenty-five cadaver heads (18 maxillae and 23 mandibles) were examined (16 male and 9 female, mean: 56.7 years). The angulation between the long axis of the anterior teeth and the alveolar process was measured, and the alveolar bone thickness was measured in the three levels (crest; C, middle; M, apex; A) on the labial and lingual sides. All data was analyzed statistically using one-way ANOVA. The maxillary anterior teeth showed two to three times more lingual inclination than the mandibular teeth. The difference in maxillary alveolar bone thickness on the labial and lingual sides was significant in all levels, particularly in the apex. The mandibular alveolar bone thickness on the labial and lingual side was significantly different only in the apex. In conclusion, the alveolar bone thickness on the anterior region was too thin, and the long axis of the maxillary anterior teeth showed more lingual inclination than the alveolar process. Therefore, clinicians need to be a detailed assessment of the labial alveolar bone for dental implant placement.
Subject(s)
Female , Humans , Male , Alveolar Process , Axis, Cervical Vertebra , Cadaver , Dental Implants , Esthetics , Head , Maxilla , ToothABSTRACT
The main aim of dental implant placement on the anterior region is to recover the function and esthetics. Therefore, this study examined the angulation between the long axis of the anterior teeth and the alveolar process, and thickness of the alveolar bone on the anterior region. Twenty-five cadaver heads (18 maxillae and 23 mandibles) were examined (16 male and 9 female, mean: 56.7 years). The angulation between the long axis of the anterior teeth and the alveolar process was measured, and the alveolar bone thickness was measured in the three levels (crest; C, middle; M, apex; A) on the labial and lingual sides. All data was analyzed statistically using one-way ANOVA. The maxillary anterior teeth showed two to three times more lingual inclination than the mandibular teeth. The difference in maxillary alveolar bone thickness on the labial and lingual sides was significant in all levels, particularly in the apex. The mandibular alveolar bone thickness on the labial and lingual side was significantly different only in the apex. In conclusion, the alveolar bone thickness on the anterior region was too thin, and the long axis of the maxillary anterior teeth showed more lingual inclination than the alveolar process. Therefore, clinicians need to be a detailed assessment of the labial alveolar bone for dental implant placement.
Subject(s)
Female , Humans , Male , Alveolar Process , Axis, Cervical Vertebra , Cadaver , Dental Implants , Esthetics , Head , Maxilla , ToothABSTRACT
PURPOSE: The cortical bone thickness on the anterior region is important for achieving implant stability. The purpose of this study was to examine the thickness of the cortical and cancellous bones on the anterior region of the maxilla and mandible. MATERIALS AND METHODS: Twenty-five cadaver heads were used (16 male and 9 female; mean death age, 56.7 years). After the long axis of alveolar process was set up, it was measured in 5 levels starting from 2 mm below the cementoenamel junction (L1) at intervals of 3 mm. All data was analysed statistically by one-way ANOVA at the .05 significance level. RESULTS: The cortical bone thickness according to measurement levels in both the labial and lingual sides increased from L1 to L5, and the lingual side below L3 was significantly thicker than the labial side on the maxilla and mandible. In particular, the labial cortical bone thickness in the maxilla was the thinnest compared to the other regions. The cancellous bone thickness according to measurement levels increased from L1 to L5 on the maxilla, and on the mandible it was the thinnest at the middle level of the root. CONCLUSION: For implant placement on the anterior region, a careful evaluation and full knowledge on the thickness of the cortical and cancellous bone are necessary, therefore, these results may provide an anatomic guideline to clinicians.