A Prospective Randomized Study Comparing Two Different Degrees of Mandibular Advancement with a Dental Appliance in Treatment of Severe Obstructive Sleep Apnea Mandibular advancement appliance for obstructive sleep apnoea: results of a randomised placebo controlled trial using parallel group design. Prospective evaluation of an oral appliance in the treatment of obstructive sleep apnea syndrome The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials Simulated driving in obstructive sleep apnoea–hypopnoea; effects of oral appliances and continuous positive airway pressure Mandibular advancement appliances and obstructive sleep apnoea: a randomized clinical trial. Two different degrees of mandibular advancement with a dental appliance in treatment of patients with mild to moderate obstructive sleep apnea A randomized, controlled crossover trial of two oral appliances for sleep apnea treatment. Mandibular advancement splints and continuous positive airway pressure in patients with obstructive sleep apnoea: a randomized cross-over trial. A randomized prospective long-term study of two oral appliances for sleep apnoea treatment. Effects of an oral appliance with different mandibular protrusion positions at a constant vertical dimension on obstructive sleep apnea Mandibular advancement splint titration in obstructive sleep apnoea Dose-dependent effects of mandibular advancement on pharyngeal mechanics and nocturnal oxygenation in patients with sleep-disordered breathing. Comparison of mandibular advancement splint and tongue stabilizing device in obstructive sleep apnea: a randomized controlled trial. 4-year follow-up of treatment with dental appliance or uvulopalatopharyngoplasty in patients with obstructive sleep apnea: a randomized study. Long-term oral appliance therapy in obstructive sleep apnea syndrome: a controlled study on temporomandibular side effects
The objective of this study was to compare the effect of two different degrees of m and ibular advancement ( MA ) , 75 % versus 50 % , on somnographic variables after 6 months of dental appliance treatment in patients with severe obstructive sleep apnea ( OSA ) . A further purpose was to compare the number of adverse events on the stomatognathic system and the effects of dental appliance treatment on the presence of daytime sleepiness . Eighty-six males with severe OSA ( apnea index ≥ 20 ) were r and omly allocated to either 75 % or 50 % MA . Forty patients in the 75 % MA group and 37 patients in the 50 % MA group completed the 6-month follow-up . The effectiveness of treatment in terms of normalization ( apnea index < 5 and apnea/hypopnea index < 10 ) with 75 % MA was 52 % , which was significantly higher ( p = 0.04 ) than the 31 % achieved with 50 % MA . The dental appliance had few adverse events on the stomatognathic system regardless of group , and the number of adverse events did not differ between the two groups . Finally , the mean value of Epworth Sleepiness Scale scores decreased significantly from 11.6 at baseline to 8.0 at follow-up ( p < 0.001 ) . No significant difference was observed between the two groups . The results indicate that a dental appliance could be an alternative treatment for some patients with severe OSA The aim of this trial was to evaluate the efficacy of a m and ibular advancement appliance ( MAA ) for obstructive sleep apnoea ( OSA ) . Ninety-three patients with OSA and a mean apnoea-hypopnoea index ( AHI ) of 34.7 were central ly r and omised into three , parallel groups : ( a ) MAA ; ( b ) m and ibular non-advancement appliance ( MNA ) ; and ( c ) no intervention . The appliances were custom made , in one piece . The MAAs had a mean protrusion of the m and ible of 74 % ( range 64 - 85 % ) . Outcome measures , assessed after continuous use for 4 weeks , were AHI ( polysomnography ) , daytime sleepiness ( Epworth ) and quality of life ( SF-36 ) . Eighty-one patients ( 87 % ) completed the trial . The MAA group achieved mean AHI and Epworth scores significantly lower ( P < 0.001 and P < 0.05 ) than the MNA group and the no-intervention group . No significant differences were found between the MNA group and the no-intervention group . The MAA group had a mean AHI reduction of 14.1 ( 95 % CI 7.4 - 20.8 ) , and a mean Epworth score reduction of 3.3 ( 95 % CI 1.8 - 4.8 ) . Eight MAA patients ( 30 % ) achieved a reduction in AHI > or = 75 % ending with an AHI < 5 , half of them having baseline AHI > 30 . Sensitivity analyses confirmed these results . MAA had a significant beneficial effect on the vitality domain of SF-36 . Four MAA patients ( 14.8 % ) and two MNA patients ( 8 % ) discontinued interventions because of adverse effects . Our conclusion is that MAA has significant beneficial effects on OSA , including cure in some cases of severe OSA . Protrusion of the m and ible is essential for the effect . MNA has no placebo effect . MAA may be a good alternative to CPAP in subsets of OSA patients The purpose of this study was to investigate the effects of an oral appliance ( OA ) , with and without m and ible advance , in the treatment of  obstructive sleep apnea syndrome ( OSA ) . Twenty-four patients diagnosed with OSA agreed to participate in this study . The patients were treated for 3 months ( with a removable soft elastic silicone positioner customized with thermoplastic silicone and with a 5-mm opening ) . Patients were selected , using a r and omized design , to receive an OA model either with ( 12 patients ) or without advance ( 12 patients ) . Before treatment , a snoring question naire , the Medical Outcomes Study 36-Item Short-Form Health Survey ( SF-36 ) , the Functional Outcomes of Sleep Question naire ( FOSQ ) , the Epworth Sleepiness Scale ( ESS ) , and polysomnography  were completed . Fifteen subjects completed the protocol ( 13 men , two women ) . With respect to basal values , the m and ible-advanced OA group presented a decrease in the mean apnea – hypopnea index ( AHI ) ( 33.8±4.7 versus 9.6±2.1 ; p<0.01 ) , number of arousals per hour ( 33.8±13.9 versus 16.0±1.5 ; p<0.05 ) , ESS score ( 14.7±5.1 versus 5.1±1.9 ; p<0.05 ) , snoring score ( 15.4±1.9 versus 10.1±3.2 ; p<0.05 ) , and total FOSQ score ( 78.1±22.6 versus 99.3±14.4 ; p<0.05 ) . After treatment , the non-advanced group presented a decrease in the mean AHI ( 24.0±12.2 versus . 11.7±7.9 ; p<0.05 ) . However , no significant differences were found in the number of arousals per hour , ESS score , snoring , and total FOSQ score in the non-advanced group . Neither study group showed significant difference in mean SF36 scores . Oral appliances , especially those that advance the m and ible , offer an effective treatment for OSA Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more Impaired simulated driving performance has been demonstrated in obstructive sleep apnoea – hypopnoea syndrome ( OSAHS ) patients . Although continuous positive airway pressure ( CPAP ) generally improves simulated driving performance , the effects of oral-appliance ( OA ) therapy are unknown . The aims of this study were to determine to what extent OSAHS patients have more difficulty with a monotonous simulated driving test when compared with control subjects and to compare the effects of OA with CPAP therapy .  Simulated driving performance was evaluated in 20 OSAHS patients and 16 control subjects during a 25-min driving test . After r and omization , ten patients started OA and CPAP therapy , respectively . After 2 to 3 months of treatment , patients repeated the driving test . At baseline , the total number of lapses of attention during driving was significantly higher in OSAHS patients as compared with control subjects . As a result of treatment , the total number of lapses of attention was significantly decreased in both the OA and CPAP group . When comparing driving performance between the OA and CPAP group , no significant differences were noted . OSAHS patients  perform worse on a simulated driving test when compared with control subjects . When evaluating the effects of treatment , adequate OSAHS management with either OA or CPAP therapy usually result ed in substantial improvements of simulated driving . Conclusions beyond both treatments improving simulated driving performance are , however , not justified by the data in the present study This r and omized placebo-controlled cross-over trial assessed the effectiveness of a m and ibular advancement appliance ( MAA ) in managing  obstructive sleep apnoea ( OSA ) . Twenty-one adults , with confirmed OSA , were provided with a maxillary placebo appliance and a MAA for 4 - 6 weeks each , in a r and omized order . Question naires at baseline and after each appliance assessed bed-partners ' reports of snoring severity ( loudness and number of nights per week ) , and patients ' daytime sleepiness ( Epworth Sleepiness Score , ESS ) . The Apnoea Hypopnoea Index ( AHI ) and Oxygen Desaturation Index ( ODI ) were measured at baseline and with each appliance during single night sleep studies . Seventy-nine per cent of subjects wore their MAA for at least 4 hours at night . Sixty-eight per cent of subjects wore their MAA for 6 - 7 nights per week . Excessive salivation was the most commonly reported complication . One subject was unable to tolerate the MAA and withdrew from the study . Among the remaining 20 subjects , the MAA produced significantly lower AHI and ODI values than the placebo . However , although the reported frequency and loudness of snoring and the ESS values were lower with the MAA than the placebo , these differences were not statistically significant . When wearing the MAA , 35 per cent of the OSA subjects had a reduction in the pre-treatment ODI to 10 or less , while 33 per cent had an AHI of 10 or less . The MAA was less effective in the subjects with the most severe OSA ( pre-treatment ODI > 50 and /or pre-treatment AHI > 50 ) The objective of this study was to evaluate the effect of 2 different degrees of m and ibular advancement , 50 % vs. 75 % of maximum protrusive capacity , on somnographic variables after 1 year of dental appliance treatment in patients with mild to moderate obstructive sleep apnea ( OSA ) . A further purpose was to compare the number of adverse events on the stomatognathic system . In a prospect i ve study , 74 male patients were r and omly allocated to receive a dental appliance with either 50 % ( 38 patients ) or 75 % m and ibular advancement ( 36 patients ) . After 1 year of treatment , 55 patients completed the follow‐up . Somnography was performed to measure treatment effects before and 12 months post‐treatment . The apnea , apnea/hypopnea , and oxygen desaturation indices decreased significantly in both groups after 1 year ( P<0.001 ) ; however , there were no differences between the groups . Normalization ( apnea index < 5 and apnea/hypopnea index < 10 ) was observed in 79 % in group 50 and in 73 % in group 75 . Few patients ( < 5 % ) reported symptoms from the stomatognathic system except for headache ( > once a week ) , which was reported in one‐third of the patients . Headache was significantly more infrequent after 1 year of treatment in both groups ( P<0.001 ) . No serious complications were observed except for 2 patients who reported a painful condition from the temporom and ibular joint in either group . In conclusion , m and ibular advancement with a dental appliance effectively reduces the sleep‐breathing disorder measured as frequency of apneas , and a pronounced m and ibular advancement did not show a greater improvement of the medical problem compared to less advancement for patients with mild to moderate OSA . On the basis of few adverse events in the stomatognathic system or other complications we can recommend dental appliance treatment and , for patients with mild to moderate obstructive sleep apnea , not starting treatment by more than 50 % m and ibular advancement Our purpose was to compare the effectiveness and side effects of a novel , single-piece m and ibular advancement device ( OSA-Monobloc ) for sleep apnea therapy with those of a two-piece appliance with lateral Herbst attachments ( OSA-Herbst ) as used in previous studies . An OSA-Monobloc and an OSA-Herbst with equal protrusion were fitted in 24 obstructive sleep apnea patients unable to use continuous positive airway pressure ( CPAP ) therapy . After an adaptation period of 156 + /- 14 d ( mean + /- SE ) , patients used the OSA-Monobloc , the OSA-Herbst , and no appliance in r and om order , using each appliance for 1 wk . Symptom scores were recorded and sleep studies were done at the end of each week . Several symptom scores were significantly improved with both appliances , but to a greater degree with the OSA-Monobloc .  Epworth Sleepiness Scale scores were 8.8 + /- 0.7 with the OSA-Herbst , and 8.6 + /- 0.8 with the OSA-Monobloc devices , and 13.1 + /- 0.9 without therapy ( p < 0.05 versus both appliances ) . The apnea/hypopnea index was 8.7 + /- 1.5/h with the OSA-Herbst and 7.9 + /- 1.6/h with the OSA-Monobloc device , and 22.6 + /- 3.1/h without therapy ( p < 0.05 versus both appliances ) . Side effects were mild and of equal prevalence with both appliances . Fifteen patients preferred the OSA-Monobloc , eight patients had no preference , and one patient preferred the OSA-Herbst device ( p < 0.008 versus OSA-Monobloc ) . We conclude that both the OSA-Herbst and the OSA-Monobloc are effective therapeutic devices for sleep apnea . The OSA-Monobloc relieved symptoms to a greater extent than the OSA-Herbst , and was preferred by the majority of patients on the basis of its simple application This prospect i ve , r and omized , cross-over trial was design ed to compare the efficacy of a m and ibular advancement splint ( MAS ) with that of nasal continuous positive airway pressure ( nCPAP ) in patients with obstructive sleep apnoea ( OSA ) . Twenty-four patients ( 20 males and four females ) with mild to moderate OSA ( AHI between 10 and 49 events per hour ) were enrolled in the study . Each patient used both MAS and nCPAP , with the initial therapy being allocated at r and om . Treatment periods lasted for two months with a two-week wash-out interval between .  Polysomnography  was performed prior to the study and after each clinical intervention . Patient and partner question naires were used to assess changes in general health and daytime somnolence . The AHI decreased from 22.2 to 3.1 using nCPAP , and to 8.0 using the MAS ( P < 0.001 for both devices ) and there was no statistically significant difference between the two treatments . The Epworth Sleepiness Score ( ESS ) fell from 13.4 to 8.1 with nCPAP , and to 9.2 with MAS ( P < 0.001 ) , again with no differences between the use of MAS or nCPAP . The question naire data showed an improvement in general health scores ( P < 0.001 ) after both treatments , but daytime sleepiness only improved significantly using nCPAP ( P < 0.001 ) . Despite this , 17 out of the 21 subjects who completed both arms of the study preferred the MAS . The splints were well tolerated and their efficacy suggests that the MAS may be a suitable alternative to nCPAP in the management of patients with mild or moderate OSA Various types of m and ibular protrusive appliances have revealed different treatment success in mild-to-moderate obstructive sleep apnoea ( OSA ) . The present study compared the long-term effect of two different appliances in the treatment of OSA . A total of 103 patients with OSA were r and omized and treated with an IST((R ) ) or Thornton Anterior Positioner ( TAP ( ) ) appliance . They were followed-up after a short-term treatment period of 6 months and long-term treatment period of over 24 months . Sleep studies in the sleep laboratory were conducted with and without the appliances , and various question naires assessing subjective daytime sleepiness , sleep quality , quality of life and symptom scores were administered at each time interval . Quality of life , sleep quality , sleepiness , symptoms and sleep outcome showed significant improvement in the short-term evaluation with both appliances , but the TAP ( ) appliance revealed a significantly greater effect . After more than 2 years of treatment , sleep outcomes revealed an equal effect with both appliances . The subjective benefits achieved initially lessened significantly . This study illustrates that both the IST((R ) ) and the TAP ( ) appliances are effective therapeutic devices for OSA after a period of over 24 months . Lack of compliance may be due to insufficient improvement in anticipated subjective symptoms and /or a recurrence of symptoms over time The aim of the study was to assess the influence of four m and ibular protrusion positions , at a constant vertical dimension , on  obstructive sleep apnea ( OSA ) . Seventeen OSA patients ( 49.2 ± 8.5 years ) received an adjustable m and ibular advancement device ( MAD ) . The patients underwent four polysomnographic recordings with their MAD in situ at , in r and om order , 0 % , 25 % , 50 % , and 75 % of the maximum protrusion . The mean apnea – hypopnea index ( AHI ) values of the patients differed significantly between the protrusion positions ( P < 0.000 ) . The 25 % protrusion position result ed in a significant reduction of the AHI with respect to the 0 % position , while in the 50 % and 75 % positions , even lower AHI values were found . The number of side effects was larger starting at the 50 % protrusion position . We therefore recommend coming to a weighted compromise between efficacy and side effects by starting a MAD treatment in the 50 % protrusion position Introduction M and ibular advancement splints ( MAS ) allowing self-adjustment may be better tolerated , but the optimum titration protocol needs systematic study . Aim The aims of the study are to assess the effectiveness of a titratable MAS device in consecutive patients with body mass index ( BMI ) < 35 kg/m2 and obstructive sleep apnoea [ OSA , apnoea – hypopnoea index ( AHI ) 10–40/h ] and compare two methods of adjustment  [ self-adjustment  or adjustment after polysomnographic ( PSG ) feedback ] . Material s and methods Twenty-eight patients ( 24 M , mean age 49 years , mean BMI 27.6 kg/m2 ) with symptomatic ( Epworth Sleepiness score > 8/24 , snoring , choking or poor sleep quality ) OSA ( mean AHI 25.7/h , range 10–46/h ) had a MAS set at 70 % maximal protrusion and were r and omised to subjective self-adjustment for 6 weeks ( n = 16 ) or objective adjustment ( n = 12 ; fixed position for 3 weeks , then PSG based feedback at 3 weeks with self-adjustment instructions ) . Primary outcome variable ( AHI ) and OSA symptoms were compared by t tests and chi-squared tests at baseline and after 6 weeks . Resolution of apnoea was defined as AHI < 5/h ; improvement was defined as AHI decreased by > 50 % but still > 5/h . Results The groups had similar baseline demographics , OSA severity and occlusal type . MAS therapy improved or resolved OSA in 20 out of 28 ( 71 % ) and was reportedly used nightly by 91 % of the objective group and 63 % of the subjective group ( p = 0.04 ) . MAS were used all night by 75 % of the objective group and 69 % of the subjective group ( p > 0.05 ) . MAS adjustment following PSG feedback did not lower AHI further from 3 weeks ( baseline 26.5 ± 12.0/h , 3 weeks 15.3 ± 13.5/h p = 0.01 , 6 weeks 11.7 ± 10.0/h , p = 0.11 ) . The overall improvement was similar to that achieved with subjective adjustment ( baseline AHI 25.4 ± 7.4/h , 6 weeks 14.3 ± 10.7/h , p = 0.0002 ) . Symptomatic benefit was reported by both groups . Conclusion In selected patients , titratable MAS improved or resolved OSA in the majority of patients and was well tolerated . PSG-based feedback at 3 weeks allowed objective confirmation of efficacy and increased device use but did not result in greater improvement in AHI or symptoms . Neither titration method was significantly superior for us to provide firm endorsement . However , we recommend a follow-up sleep study to confirm MAS efficacy STUDY OBJECTIVES To examine dose-dependent effects of m and ibular advancement on collapsibility of the passive pharynx and sleep-disordered breathing ( SDB ) . DESIGN Prospect i ve , r and omized study . SETTING University hospital . PATIENTS Thirty-seven adult patients with SDB . INTERVENTIONS Oral appliances with 2- , 4- , and 6-mm advancement of the m and ible . MEASUREMENTS AND RESULTS Overnight oximetry was performed with and without oral appliances . Each 2-mm m and ibular advancement coincided with approximately 20 % improvement in number and severity of nocturnal desaturations . Percentages of patients producing a > 50 % improvement rate of the number of desaturations were 25 % , 48 % , and 65 % with use of oral appliances with 2- , 4- , and 6-mm m and ibular advancement , respectively . Static pharyngeal mechanics were evaluated in six completely paralyzed patients with SDB under general anesthesia with and without the oral appliances . Advancement of m and ibular position was found to produce dose-dependent closing pressure reduction of all pharyngeal segments . Normalization of nocturnal oxygenation was associated with negative closing pressure , especially at the velopharynx . CONCLUSIONS We conclude that improvement of both nocturnal oxygenation and pharyngeal collapsibility significantly depends on the m and ibular position STUDY OBJECTIVES To compare the efficacy of a m and ibular advancement splint ( MAS ) and a novel tongue stabilizing device ( TSD ) in the treatment of  obstructive sleep apnea ( OSA ) .  DESIGN A r and omized crossover design was used . PATIENTS Twenty-seven patients ( 20 male , 7 female ) , recruited from a tertiary hospital sleep clinic . MEASUREMENTS AND RESULTS The apnea-hypopnea index ( AHI ) was reduced with MAS ( 11.68 + /- 8.94 , P = 0.000 ) and TSD ( 13.15 + /- 10.77 , P = 0.002 ) compared with baseline ( 26.96 + /- 17.17 ) . The arousal index decreased for MAS ( 21.09 + /- 9.27 , P = 0.004 ) and TSD ( 21.9 + /- 10.56 , P = 0.001 ) compared with baseline ( 33.23 + /- 16.41 ) . Sixty-eight percent of patients achieved a complete or partial response with MAS , compared with 45 % with TSD . The Epworth Sleepiness Scale ( ESS ) score was decreased with MAS ( P = < 0.001 ) and TSD ( P = 0.002 ) . Subjective improvements in snoring and quality of sleep were reported , with a better response for MAS than TSD .  Compliance was poorer for TSD , and the side effect profiles of the 2 modalities were different . All patients were satisfied with MAS compared to TSD , and 91 % of patients preferred the MAS . CONCLUSION Objective testing showed the MAS and TSD had similar efficacy in terms of AHI reduction . Patients reported improvements with both devices ; however , better compliance and a clear preference for MAS was apparent when both devices were offered . Longer term studies are needed to clarify the role of TSD STUDY OBJECTIVES To evaluate the effects of treatment with a dental appliance or uvulopalatopharyngoplasty ( UPPP ) on somnographic variables in patients with mild-to-moderate obstructive sleep apnea ( OSA ) followed up for 4 years , and compliance and complementary treatment . DESIGN R and omized study . SETTING Central Hospital , Västerås , Uppsala University , Sweden . PATIENTS Ninety-five male patients with confirmed mild-to-moderate OSA ( apnea index [ AI ] > 5 and < 25 ) were r and omized to treatment with a dental appliance or UPPP .  Sleep studies were performed before and 1 year and 4 years after intervention . Thirty-two patients in the dental-appliance group and 40 patients in the UPPP group completed the 4-year follow-up . RESULTS The success rate ( percentage of patients with at least 50 % reduction in AI ) in the dental-appliance group was 81 % , which was significantly higher than in the UPPP group , 53 % ( p < 0.05 ) . Normalization ( AI < 5 or apnea/hypopnea index < 10 ) was observed in 63 % of the dental-appliance group and 33 % of the UPPP group after 4 years . The difference between the groups was significant ( p < 0.05 ) . The compliance to use of the dental appliance was 62 % at the 4-year follow-up . Thirty patients ( 75 % ) in the UPPP group continued without complementary treatment . The dental appliances had few adverse effects on the stomatognathic system , and the number of adjustments and repairs of the appliances over time was moderate . Pronounced complaints of nasopharyngeal regurgitation of fluid and difficulty with swallowing after UPPP were reported by 8 % and 10 % , respectively . CONCLUSIONS The dental-appliance group showed significantly higher success and normalization rates regarding the somnographic variables compared to the UPPP group , but the effectiveness of the dental appliance was partly invali date d by the compliance of 62 % at the 4-year follow-up . However , the appliances had few adverse effects on the stomatognathic system and required only moderate adjustments . Use of a dental appliance with regular follow-up can be recommended for long-term treatment of OSA The objective of this study was to assess variations in the occurrence of temporom and ibular disorders ( TMDs ) and the risk of developing pain and function impairment of the temporom and ibular complex in obstructive sleep apnea syndrome ( OSAS ) patients treated with either an oral appliance ( m and ibular advancement device )  or continuous positive airway pressure ( CPAP )  in a 2-year follow-up study . In addition , we assessed the relationship between the mean m and ibular protrusion and the frequency of wearing the appliance during follow-up with the occurrence of pain and function impairment of the temporom and ibular complex . Fifty-one patients were r and omized to oral appliance therapy and 52 patients to CPAP therapy .  TMDs ( diagnosed according to the Axis I Research Diagnostic Criteria for TMD ) , pain intensity and disability and m and ibular function impairment were recorded at baseline , after 2 months , 1 year and 2 years of therapy . Only in the initial period of treatment the occurrence of pain-related TMDs was considerably higher ( 24 % ) in the oral appliance group compared to CPAP ( 6 % ) . Oral appliance therapy furthermore result ed in more temporom and ibular pain compared to CPAP ( odds ratio 2.33 , 95 % confidence interval ( 1.22–4.43 ) ) . However , there were no limitations in m and ibular function in both groups during the ( entire ) follow-up period . Although generally not serious and of transient nature , oral appliance therapy results in more pain-related TMDs in the initial period of use compared with CPAP therapy . Oral appliance therapy is associated with increased pain in the temporom and ibular complex in the initial period of use . Because of the transient nature , this pain is not a reason to contra-indicate an oral appliance in OSAS patients . Moreover , TMDs and the risk of developing pain and function impairment of the temporom and ibular complex appear limited with long-term oral appliance use
Purpose The therapy with m and ibular advancement devices ( MADs ) represents a treatment option for patients with obstructive sleep apnea ( OSA ) .
The literature does not provide evidence regarding the most effective m and ibular advancement ; therefore , the aim of this systematic review with meta-regression was to investigate the effectiveness of different m and ibular advancement amounts in reducing  apnea-hypopnea index ( AHI ) in OSA patients .