| Purpose: After the loss of a maxillary molar,the presence of physiological resorption of the alveolar bone and pneumatization of the maxillary sinus often results in insufficient vertical bone volume in the maxillary molar area,which affects the normal performance of the implant placement procedure.In this study,we compared three surgical options:direct placement of short implants,simultaneous placement of short implants after maxillary sinus floor lift,and simultaneous placement of conventional implants after maxillary sinus floor lift,and the clinical results observed 12 months after restoration,to investigate the preferred option for implants in patients with vertical bone deficiency in the maxillary posterior region.Methods: Sixty-one patients(83 implants)who needed maxillary first or second molar implant restorations were selected from September 2020 to January 2022 at the Affiliated Stomatological Hospital,School of Stomatology,Dalian Medical University Hospital.Among them,there were 42 Thommen short implants and 41 Osstem short implants.All patients had vertical bone height(3.5-8.5)mm and buccal-palatal width >5.5 mm in the maxillary molar area.32 males and 29 females were involved;the mean age was 53.70(19-75)years,and there was no statistical difference between male and female age(P > 0.05).All implants were randomly divided into three groups,A,B,and C.There was no statistical difference in the original vertical bone height between the three groups(P > 0.05).The 83 implants were divided into three groups,A,B,and C.Group A: The vertical bone height of the maxillary molar area(7.0～8.5)mm was directly implanted with short implants,and a total of 26 implants were placed in 17 patients.Among them,14 Thommen short implants of 4.5mm/5.0mm/6.0mm in diameter and 6.5mm/8.0mm in length were used.12 Osstem short implants with two types of 4.5mm/5.0mm diameter;7.0mm length.Group B: The vertical bone height of the maxillary molar area(3.5-8.0)mm,the maxillary sinus floor lift was used to place the short implants at the same time.26 implants were placed in 18 patients.Among them,there were 13 short implants of4.5mm/5.0mm/6.0mm in diameter and 6.5mm/8.0mm in length.There are 13 short implants of Thommen.Thirteen Osstem short implants.The two types of implants are4.5mm/5.0mm in diameter and 7.0mm in length.Group C: Maxillary molar area with vertical bone height(3.5 ～ 8.0)mm,using maxillary sinus floor elevation to place conventional implants at the same time.31 implants were placed in 26 patients.Among them,15 conventional implants were placed by Thommen,with two types of4.5mm/5.0mm diameter and two types of 9.5mm/11 mm length.There were 16 Osstem conventional implants with 4.5mm/5.0mm diameter and 8.5mm/10mm/11.5mm length.All implant patients were treated with a twice-approach procedure and operated according to surgical specifications.The maxillary sinus floor was lifted internally using a maxillary sinus apex punch and the bone graft material was uniformly Bio-Oss bone powder.The second stage surgery was performed 4 or 6 months after the implantation.The impressions were taken and the upper denture restoration was completed 2 to 3weeks after the second stage surgery.Cases of failed first-stage surgery were not counted in the post-restoration analysis.the evaluation of implants in groups A,B and C consisted of:1.Success rate and retention rate of implants in the first stage of implant surgery;record and compare the height of elevation in the maxillary sinus floor between group B and group C.2.The retention rate and clinical examination of the implants after restoration: the retention rate of the implants were counted immediately and 3,6 and 12 months after the restoration,and the clinical indexes were examined and compared: the probing pocket depth(PPD),the modified plaque index(m PLI),the modified sulcus bleeding index(m S),and the peri-implant depth.m SBI(modified sulcus bleeding index).3.Imaging: Radiographic apical films were taken immediately and 3,6 and 12 months after restoration to measure and compare marginal bone loss(MBL)of the implants.4.Patient satisfaction: Satisfaction scores were designed to range from 0 to 10,and patient satisfaction was recorded and compared for the first stage of surgery.4.Patient satisfaction: A satisfaction score ranging from 0 to 10 was designed to record and compare patient satisfaction with the first stage of the procedure.Results:1.Success rate and retention rate of implants in phase I surgery The success rate and retention rate of the implants in the three groups A,B and C were the same,100%,94.12% and 100% respectively;the height of the elevated bone in the maxillary sinus floor immediately after surgery was(1.85±0.75)mm and(3.75±2.05)mm in groups B and C respectively,and the difference between the height of the elevated bone in the maxillary sinus floor in groups B and C was statistically significant(P<0.05).2.Retention rate of implants after restoration and clinical examination(1)Retention rate of implants after restoration: The retention rates of implants in groups A,B and C were 100% immediately and 3,6 and 12 months after restoration.(2)Clinical examination:(1)The differences between implant groups A,B and C in terms of PPD,m PLI and m SBL at 3,6 and 12 months after restoration were not statistically significant(P>0.05).(2)The differences between PPD,m PLI,and m SBL at3,6,and 12 months after restoration were not statistically significant when comparing within implant groups A,B,and C(P > 0.05).(3)The differences between PPD,m PLI,and m SBI at 3,6,and 12 months after restoration were not statistically significant(P >0.05)when comparing the two types of implants,Thommen and Osstem,respectively.3.3.Imaging examination(1)When comparing patients in groups A,B and C between groups,the differences between MBL at 3,6 and 12 months after repair were not statistically significant(P >0.05).(2)The differences between MBL at 3,6,and 12 months after repair were statistically significant(P < 0.05)when comparing patients in groups A,B,and C within the groups.(3)The differences between MBL at 3,6 and 12 months after restoration were not statistically significant(P > 0.05)when comparing the two types of implants,Topaz and Odontoc,within 12 months after restoration.4.Patient satisfaction: The differences between Group A and Group B,and between Group A and Group C for Phase I surgery patient satisfaction were statistically significant(P < 0.05),while the differences between Group B and C for Phase I surgery patient satisfaction were not statistically significant(P > 0.05).Conclusion:1.In the case of insufficient vertical bone height in the maxillary molar area,the use of short implants can achieve the desired clinical results within 12 months after restoration.2.Due to the limitations of this study,further research is needed regarding the clinical outcome of a single restoration with short implants. |
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